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Controlling the head

Subclass of:

360 - Dynamic magnetic information storage or retrieval

360069000 - AUTOMATIC CONTROL OF A RECORDER MECHANISM

Patent class list (only not empty are listed)

Deeper subclasses:

Class / Patent application numberDescriptionNumber of patent applications / Date published
360770010 Track centering 260
360780010 Track changing 39
360076000 Azimuth or skew 14
Entries
DocumentTitleDate
20090122436Control of Transducer to Tape Spacing - A tape drive apparatus for reading and writing data on a magnetic tape includes at least one transducer that interacts with the magnetic tape. A temperature control element is positioned to thermally expand the transducer. A control system controls the amount of current supplied to the temperature control element. A sensing circuit senses the distance between the transducer and the data storage tape. The system generates a spacing signal indicative of the sensed distance and is stored as spacing data. A temperature control element is controlled based upon spacing data to adjust the spacing between the transducer and the tape. The temperature control element may be controlled based upon a fixed adjustment or empirical data. A method is disclosed for controlling spacing between the transducer and a magnetic storage tape by heating the transducer head to cause thermal expansion and reduce pole tip recession.05-14-2009
20090296261DISK DRIVE AND MAGNETIC CIRCUIT FIXING METHOD FOR THE SAME - A disk-drive magnetic circuit fixing structure and fixing method for fixing a magnetic circuit to a base by means of a plurality of screws, wherein provisions are made to substantially prevent a microscopic sliding movement involving impulsive vibration from occurring at a fastening portion between the magnetic circuit and the base. More specifically, in a disk drive including a disk enclosure having a base and a cover, a magnetic head contained within the disk enclosure, and a driving coil motor for driving the magnetic head by working in combination with an actuator on which the magnetic head is mounted and a magnetic circuit disposed in the vicinity of the actuator, the magnetic circuit is fixed to the base with a single or a plurality of screws by applying in advance a lubricant forming a lubricating layer on a face where each screw contacts the magnetic circuit or the base.12-03-2009
20090195914HARD DISK DRIVE AND METHOD FOR DESIGNING ADDITIONAL CONTROLLER INCLUDED IN HARD DISK DRIVE - A hard disk drive is provided. The hard disk drive comprises a plant configured to drive the hard disk drive, a main controller configured to control the plant, and an additional controller connected in parallel with the main controller. A response function in consideration of the plant and the main controller is referred to as a main response function, and a response function in consideration of the plant and the additional controller is referred to as a first response function. The first response function cancels a function value corresponding to a section of the main response function that is associated with disturbance. The response function of the additional controller may be designed using the first response function. The hard disk drive removes a portion of the main response function to minimize the influence of the disturbance.08-06-2009
20090195912DISK DRIVE THAT CALIBRATES THE POWER FOR SETTING THE DYNAMIC FLY HEIGHT OF THE HEAD TO A TARGET VALUE - According to one embodiment, a measuring module measures the dynamic flying height of a head. A change calculation module calculates a change ΔDFHPt in a reference power optimal for setting a first dynamic flying height, based on the difference between a second dynamic flying height, which has a value measured by the measuring module while the reference power is being supplied to a adjusting element, and the first dynamic flying height. A controller changes the power to be supplied to the adjusting element, by the change ΔDFHPt calculated by the change calculation module.08-06-2009
20090195909GAIN CONTROL FOR DATA-DEPENDENT DETECTION IN MAGNETIC STORAGE READ CHANNELS - Method, apparatus and computer program product adjust gain in a read channel of a magnetic media data storage device. A digital signal sample having a data-dependent noise component is received. A gain value, stored in a location in a gain table, is selected in a data-dependent manner. The gain of the signal sample is adjusted in response to the selected gain value. A bit pattern is detected from the gain-adjusted signal sample and a data output signal is output based upon the detected bit pattern.08-06-2009
20100149681RECORDING METHOD AND STORAGE DEVICE - According to one embodiment, a recording method includes: skipping a track by a skip amount in a skip region smaller than an overall recording region on a magnetic recording medium by using an extra region that is unnecessary for securing a storage capacity to be provided by a storage device, the extra region being on the recording surface of the magnetic recording medium; and recording data while skipping the track in the skip region, wherein the skip region is set to a region in which a track to be recorded on the magnetic recording medium is expected to influence an adjacent track in accordance with at least one of a condition and a state of the storage device.06-17-2010
20100053798Information Recording and Reproducing Apparatus, Information Recording and Reproducing System, Information Processing Apparatus and Information Reproducing Apparatus - An information recording and reproducing apparatus 03-04-2010
20090067082PATTERNED-MEDIA MAGNETIC RECORDING DISK AND DISK DRIVE WITH DATA ZONES HAVING NONDATA REGIONS NEAR THE ZONE BOUNDARIES - A patterned-media magnetic recording disk has data islands arranged into concentric data tracks and the data tracks arranged into radially-spaced annular zones, with each zone having an inside-diameter (ID) perimeter and an outside-diameter (OD) perimeter and at least one annular nondata region near one of its perimeters. Each zone includes generally radially-directed synchronization (sync) marks that extend from the zone ID perimeter to the zone OD perimeter so as to extend into the annular nondata region or regions of the zone. In the disk drive that uses the patterned-media disks the read head and write head have an effective radial offset relative to one another, so the write head may be on a data track near a zone perimeter when the read head is located in a nondata region. The read head detects the sync marks that extend into the nondata region so that the write head can be synchronized with the data islands in the data track.03-12-2009
20110188153Method of Retaining a Magnetically Preloaded Anti-Rotation Guide for a Transducer - A transducer positioning apparatus is provided that supports a read/write head on a data storage machine and biases the head against rotation. The transducer positioning apparatus may comprise a base that includes a linear drive motor and a support frame to which the read/write head is secured. The support frame is reciprocally driven by the linear drive motor relative to the base. A magnetic coupling is provided between the base and the support frame that resists movement of the frame other than the reciprocal movement of the support frame relative to the base. A method is also disclosed for magnetically biasing a movable head of a transducer against rotation.08-04-2011
20080259486METHODS FOR ENABLING FUNCTIONALITY IN MULTI-MODAL DATA STORAGE SYSTEMS - A method for enabling different modes on a multi-modal data storage system such as a tape-based data storage system includes enabling a data storage system to operate in at least one of two modes, a first of the modes being different than a second of the modes. In one embodiment, the data storage system has all physical components required to operate in the first and second modes. An ability to operate in at least one of the modes is not allowed prior to enabling the data storage system to operate in the at least one of the modes.10-23-2008
20110194207METHOD OF PRODUCING MAGNETIC STORAGE MEDIUM, MAGNETIC STORAGE MEDIUM AND INFORMATION STORAGE DEVICE - It is an object to provide a simple method capable of producing a magnetic storage medium, a magnetic storage medium and an information storage device which may be produced by a simple production method with a high recording density, and a magnetic disk is produced by a production method having: a film-forming process of forming, on a substrate 08-11-2011
20110194206Power-Supply Unit, Hard-Disk Drive, and Switching Method of the Power-Supply Unit - A power-supply unit which comprises a transformer, a full bridge circuit consisting of four arm switches provided on a primary side of the transformer, a rectifier and smoothing circuit including two synchronous rectifier switches provided on a secondary side of the transformer, a choke coil, and a capacitor, an output terminal provided in the rectifier and smoothing circuit, a control circuit controlling ON/OFF of the four arm switches of the full bridge circuit and the two synchronous rectifier switches of the rectifier and smoothing circuit, a resonant inductor consisting of a leakage inductor component of the transformer and a parasitic inductor component of wirings on the primary side of the transformer, and a resonant capacitor consisting of a parasitic capacitor component of the arm switches of the full bridge circuit, and in which the control circuit comprises timing variable means which varies switching timings of the two synchronous rectifier switches of the rectifier and smoothing circuit based on an output current flowing in the output terminal provided in the rectifier and smoothing circuit.08-11-2011
20130077189LOW CLEARANCE MAGNETIC HEAD HAVING A CONTACT DETECTION SENSOR - According to one embodiment, a magnetic data system includes a magnetic disk medium, a magnetic head having a writer element and/or a reader element, an exothermic resistor element for thermal fly-height control (TFC), a contact detection sensor having a resistor element and at least one contact detection electrode, and an insulating film on a medium facing side of the magnetic head to protect the contact detection sensor, the insulating film having a thickness greater than the contact detection electrode, a drive mechanism for passing the magnetic disk medium over the magnetic head, and a controller electrically coupled to the magnetic head for controlling operation of the magnetic head, wherein the controller adjusts magnetic spacing between the magnetic head and the magnetic disk medium via thermal distortion of the exothermic resistor element. The contact detection sensor may be used as a second TFC resistor element.03-28-2013
20100073805FLYING HEIGHT CONTROL DEVICE FOR MAGNETIC HEAD, AND MAGNETIC DISK DEVICE - A flying height control device controls a flying height of a magnetic head and reports the state of the flying height control of a magnetic disk device to a host, using self monitoring, analysis and reporting functions. A function to control a flying height by controlling the heat power of a heater element of a magnetic head is added to functions of the self monitoring, analysis and reporting. And self recovery of the read performance is performed by correcting the heater power, and the heater power correction state using this function is reported to the host. Before data is lost, processing to avoid data loss can be started, and this function can be implemented simply by adding the heater power correction function since data of the self monitoring, analysis and reporting functions is utilized, thereby enabling easy installation.03-25-2010
20090122438DESIGN OF FEEDFORWARD CONTROLLER FOR CONTROLLING POSITION OF MAGNETIC HEAD IN MAGNETIC DISK DRIVE - For a feedforward controller for controlling a position of a magnetic head in a magnetic disk drive, a vibration of the magnetic head is measured in a state in which a magnetic disk is rotated in the magnetic disk drive. From a spectrum of the measured vibration, a flutter frequency which is a frequency of a vibration caused by the magnetic disk fluttering is obtained. A filter is designed for each flutter frequency having a peak of a gain for a respective one of obtained flutter frequencies. The feedforward controller for controlling a position of the magnetic head is obtained by combining filters designed for the respective flutter frequencies.05-14-2009
20130083421HEAD ROTATOR ASSEMBLY FOR TAPE DRIVE - A head rotator assembly (04-04-2013
20100157467Quiet Retraction System - A quiet retraction method for regulating constant velocity while parking an arm within a disk drive is described. The method comprises the steps of: driving a motor for the arm using a first drive current for a first period; floating the motor; sampling a back electromotive force (bemf) for a first sampled voltage, while floating the motor; driving the motor with a second drive current during a second period in response to sampling the bemf; determining whether the second drive current exceeds a current limit; estimating the bemf using the first sampled voltage when the second drive current exceeds the current limit; driving the motor with a third current during a third period in response to estimating the bemf; wherein driving the motor with the first, second, and third currents quietly parks the arm, while regulating the constant velocity.06-24-2010
20100118434STORAGE APPARATUS AND CONTROL METHOD OF STORAGE APPARATUS - According to one embodiment, a storage apparatus includes: a storage medium configured to include a plurality of tracks; a head configured to write data to the storage medium; an auxiliary storage module configured to be able to store the data; and a controller configured to determine, during data writing, a write start position of the data, move the head to a track to which the data is to be written, start writing the data along the track when the head reaches the track, and store a piece of the data to be written between the write start position and the position where the data is started to be written into the auxiliary storage module.05-13-2010
20100073806Magnetic recording head and magnetic recording apparatus - It is made possible to improve the recording resolution. A magnetic recording head includes: a magnetic pole that has a first magnetic portion including an air bearing surface, and generates a write magnetic field; and a spin torque oscillator that is formed on the air bearing surface of the magnetic pole, and is formed with a stack structure including a first magnetic layer, a second magnetic layer, and a nonmagnetic layer interposed between the first magnetic layer and the second magnetic layer, the second magnetic layer generating a high-frequency magnetic field when current is applied between the first magnetic layer and the second magnetic layer.03-25-2010
20090251820INTEGRATED SERVO AND READ EMR SENSOR - A magnetic storage system according to one embodiment includes magnetic media containing magnetic domain tracks; and at least one head for reading from the magnetic media, each head having: a first Extraordinary Magentoresistive (EMR) device for detecting magnetic fields of a first magnetic domain track; a second EMR device for detecting magnetic fields of a second magnetic domain track. The system further includes a slider for supporting the head; and a control unit coupled to the head for controlling operation of the head. A system according to another embodiment includes a first Extraordinary Magnetoresistive (EMR) device for detecting magnetic fields of a magnetic domain of interest. A system according to yet another embodiment includes an Extraordinary Magnetoresistive (EMR) device for deriving servoing information.10-08-2009
20130083425MANUFACTURING METHOD OF GLASS SUBSTRATE FOR MAGNETIC DISK, MAGNETIC DISK, AND MAGNETIC RECORDING / REPRODUCING DEVICE - A manufacturing method of a glass substrate for a magnetic disk is provided whereby nano pits and/or nano scratches cannot be easily produced in polishing a principal face of a glass substrate using a slurry containing zirconium oxide as an abrasive. The manufacturing method of a glass substrate for a magnetic disk includes, for instance, a polishing step of polishing a principal face of a glass substrate using a slurry containing, as an abrasive, zirconium oxide abrasive grains having monoclinic crystalline structures (M) and tetragonal crystalline structures (T).04-04-2013
20130083420METHOD FOR CREATING BURST MAGNITUDE SERVO PATTERNS WITH UNIPOLAR BITS ON A MAGNETIC MEDIA OF A MAGNETIC DATA RECORDING SYSTEM - A magnetic data storage system having a magnetic disk having burst patterns for providing a position error signal (PES) wherein each magnetic burst pattern is offset from an adjacent burst pattern by ¼ track pitch. All of the magnetic bits of the burst patterns can be unipolar magnetized, and the bits of each burst pattern can be aligned with one another in radial and circumferential direction. The magnetic media can be a bit patterned media wherein the magnetic bits of the burst patterns are magnetically isolated portions separated by non-magnetic spaces or non-magnetic material.04-04-2013
20130083422LUBRICANT LAYER THAT PROVIDES A STABLE HEAD-TO-DISK INTERFACE IN HUMID CONDITIONS - In one embodiment, a magnetic disk medium includes a nonmagnetic substrate, a magnetic recording layer above the nonmagnetic substrate, a protective layer above the magnetic recording layer, and a lubricant layer above the protective layer, the lubricant layer including a mixture of a compound having one or more cyclophosphazene groups and a lubricant formulated R1-OCH04-04-2013
20130033782SPINDLE MOTOR AND HARD DISC DRIVE INCLUDING THE SAME - There are provided a spindle motor and a hard disk drive including the same. The spindle motor includes: a shaft; a sleeve rotatably supporting the shaft by fluid dynamic pressure; a holder provided outwardly of the sleeve and at least partially formed of a magnetic material; a stator core mounted on an outer surface of the holder; and a base member including a mounting part protruding upwardly in an axial direction and fixed to the holder.02-07-2013
20130033781BASE FOR MOTOR AND HARD DISK DRIVE INCLUDING THE SAME - There is provided a base for a motor, the base including: a base body having a disk disposed thereon; an outer wall part formed on the base body to thereby define an outer edge of the base body; and a fixing part formed in at least one of the base body and the outer wall part in order to fix the base body and a substrate, to which power is applied, to each other, thereby supporting upper and lower surfaces of the substrate.02-07-2013
20130033780Base for motor and hard disk drive including the same - There is provided a base for a motor, the base including: a base body formed of a steel plate through a pressing process; and an outer wall part defining an exterior of the base body, in which the outer wall part has a thickness smaller than a thickness of the steel plate in order to increase a contact area with a sealing part.02-07-2013
20130033779AIR BEARING SURFACE OVERCOAT WITH SOFT INTERMEDIATE FILM, AND METHODS OF PRODUCING THE SAME - In one embodiment, a magnetic head includes at least one magnetic head element for reading from and/or writing to a magnetic medium, the element having an air bearing surface (ABS) facing toward a magnetic medium, an adhesive film including silicon nitride above the ABS having a characteristic of being formed under a water vapor partial pressure, and a protective film above the adhesive film, the protective film including carbon. Also, in another embodiment, a method includes forming an ABS of a magnetic head, the ABS being a surface of the magnetic head which is closest to a magnetic medium when in use, forming an adhesive film above the ABS of the magnetic head, the adhesive film being formed under a water vapor partial pressure, and forming a protective film above the adhesive film, the protective film including carbon.02-07-2013
20090059413Adjusting a fly-height in hard disk drives - A method for increasing reliability of a hard disk drive (HDD) is disclosed. One of a plurality of magnetic read/write heads in a hard disk drive (HDD) is determined to be disabled, and a fly-height associated with the disabled read/write head is increased with respect to a fly-height associated with the plurality of read/write heads.03-05-2009
20100046111RECORDING HEAD AND DATA RECORDING AND REPRODUCING APPARATUS - There is provided a recording head 02-25-2010
20100097717REDUCING THE SPECTRAL ENERGY OF TORQUE RIPPLE - In BLDC motors driven via sensorless techniques, the BEMF signals in the motor coils may be used to detect the position of the motor such that speed of the motor may be accurately controlled. When detecting the BEMF signals, however, small perturbations occur which negatively impact the rotational torque of the motor. As a result, torque ripple may occur at regular intervals which may result in inefficiencies as well as audible noise. In various embodiments as described herein, the sampling of the BEMF signals may be done so at pseudo-random intervals such that the overall spectral energy that presents from the BEMF detections may be reduced at specific frequencies (such as fundamental sampling frequencies and harmonics thereof) and spread out over many more frequencies. Thus, despite the overall spectral energy being the same, the amplitude of any given frequency is lower as the sampling of the BEMF is less periodic.04-22-2010
20100110580MAGNETIC DISK DEVICE - A magnetic disk device includes a disk that includes a plurality of tracks and magnetically stores therein data; a magnetic head that reads and writes data on the tracks; a data writing unit that classifies sectors along one track into a plurality of sector groups and writes to a physical address of each of the sector groups data of a logical address that is different from a logical address corresponding to the physical address in same track; and a first nonvolatile memory that stores therein a conversion table of the logical address and the physical address.05-06-2010
20090268335NEUTRALIZING FLYING HEIGHT SENSITIVITY OF THERMAL POLE-TIP PROTRUSION OF MAGNETIC SLIDER - A method for neutralizing the flying height sensitivity associated with thermal pole-tip protrusion (T-PTP) of an air bearing slider comprises creating head material data and air bearing surface (ABS) compensation data, based on which a head/ABS design is created. The head material data comprises at least one material property that is dependent on the manner in which the material is fabricated, such as the coefficient of thermal expansion of a material deposited using a certain deposition process. The ABS compensation data comprises data about how respective ABS features affect air bearing pressure and, therefore, ABS compensation. A protrusion profile is determined for the head/ABS design, and whether or not this protrusion profile meets particular design criteria is then determined. The head/ABS creating and determining process can be iterated if necessary to arrive at a head/ABS design which provides neutral flying height sensitivity to a range of operational temperatures.10-29-2009
20090154003Systems and Methods for Using an On-the-fly CBD Estimate to Adjust Fly-Height - Various embodiments of the present invention provide systems and methods for using channel bit density estimates to adjust fly-height. For example, various embodiments of the present invention provide methods for adaptively adjusting fly-height. Such methods include providing a storage medium that includes information corresponding to a process data set, and a read/write head assembly that is disposed a variable distance from the storage medium. The process data set is accessed from the storage medium. A first channel bit density estimate is adaptively calculated based at least in part on the process data set and a second channel bit density estimate that was previously calculated. The variable distance is modified based at least in part on the first channel bit density estimate. A third channel bit density is adaptively calculated based at least in part on the process data set and a fourth channel bit density estimate that was previously calculated. The variable distance is modified based at least in part on the third channel bit density estimate.06-18-2009
20090154002METHODS AND APPARATUS TO CONTROL HEAD EXPANSION IN MULTI-HEAD HARD-DISK DRIVES - Methods and apparatus to control head expansion in multi-head hard-disk drives are disclosed. An example control system for use in a multi-head hard-disk drive includes a first sensor to provide a first feedback signal indicating a status of a first head; a second sensor to provide a second feedback signal indicating a status of a second head; and a shared calculation unit to selectively receive one of the first and second feedback signals for a feedback process to control an expansion of the first and second heads.06-18-2009
20130027806Method and apparatus for writing and using servo correction data - Methods and apparatuses for generating and using servo correction data are disclosed. In one embodiment, an apparatus may comprise a data storage medium having a first track and a second track, servo correction data for the first track and the second track stored on the first track, and no servo correction data stored on the second track, and a controller configured to correct servo errors based on the servo correction data. In another embodiment a method may comprise receiving servo information related to a first data storage medium having a first track and a second track, generating one or more position error signals (PES) based on the servo information, generating servo correction data based on the one or more PES, and storing the servo correction data for the first track and the second track on the first track.01-31-2013
20100067141MAGNETIC RECORDING MEDIUM, METHOD OF MANUFACTURING MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING/REPRODUCING APPARATUS - The present invention provides a magnetic recording medium that has sufficient recording/reproducing characteristics and good write characteristics and can correspond to high recording density, and a method of manufacturing the same. A magnetic recording medium 03-18-2010
20130083423MAGNETIC STORAGE APPARATUS, HEAD DRIVE CONTROLLER, AND HEAD DRIVE CONTROL METHOD - A magnetic storage apparatus includes a magnetic recording medium, a microwave assisted magnetic recording head at least equipped with a magnetic recording pole that generates a recording magnetic field for writing to the magnetic recording medium and a high-frequency oscillator that generates a high-frequency field, a magnetic reproducing head that reads information from the magnetic recording medium, a signal processing unit that processes a signal written by the magnetic recording head and a signal read by the magnetic reproducing head and a unit that controls clearance between the high-frequency oscillator and the magnetic recording medium. The magnetic storage apparatus has a characteristic that the high-frequency oscillator is not operated except in recording.04-04-2013
20130083424MAGNETIC DISK DEVICE AND HEAD-POSITION CONTROL METHOD - A magnetic disk device includes a magnetic disk on which servo information is recorded, a head to read the servo information of the magnetic disk, and a position control module. When carrying out positioning control of the head, the position control module estimates frequency components of noise in a head positioning control process, using a high-order digital filter that includes first and second variable coefficients that are each based on position error information generated from the servo information read by the head.04-04-2013
20120182642HARD DISK DEVICE, DISK, AND METHOD FOR CALCULATING DISPLACEMENT AMOUNT OR POSITION CORRECTION AMOUNT OF HEAD - A hard disk device includes a disk, a head, and a calculator. The disk includes a plurality of first areas arranged spaced apart in the circumferential direction on a surface of the disk and data-rewritable second areas each located between an adjacent pair of the first areas in the circumferential direction. First servo data is written in the first areas, while second servo data is written in the second areas. The head reads the first servo data and the second servo data written to the surface of the disk. The calculator calculates a displacement amount or a position correction amount of the head based on a result of reading the first servo data and the second servo data by the head.07-19-2012
20120182641Hard Disk Drive Availability Following Transient Vibration - A method and computer program product for sending a data request from a host bus adapter logic processor to a hard disk drive, setting a standard time out period for receiving a reply from the hard disk drive, sensing vibration in the hard disk drive, sending a vibration alert signal from the hard disk drive to the host bus adapter logic processor in response to the sensed vibration exceeding a predetermined amount of vibration, and, in response to receiving the vibration alert signal from the hard disk drive, the host bus adapter logic processor establishing an extended time out period for receiving the reply. The rotational vibration sensor used by the hard disk drive for repositioning the read/write head may also be used to sense the vibration and form the basis for the vibration alert signal, such as a vibration error code. By extending the time out period during high vibration events, the hard disk drive can ride out the event without being tagged as having failed. Accordingly, the hard disk drive can then be available for use following the high vibration event.07-19-2012
20130070367MAGNETIC RECORDING HEAD AND MAGNETIC RECORDING APPARATUS - A spin torque oscillator for microwave assisted recording includes a perpendicular free layer having a magnetic anisotropy axis in a direction perpendicular to a film surface, and an in-plane free layer composed of a magnetic film effectively having a magnetization easy plane on a film surface. When electric currents flows from the in-plane free layer side to the perpendicular free layer side, both free layers exchange spin information and thereby rotate their respective magnetizations almost antiparallel to each other and along a boundary surface with high-speed. Preferably, the perpendicular free layer is thinner than the in-plane free layer. It is also preferable that a magnetic anisotropy field of the perpendicular free layer attributable to materials should balance, in reverse directions, with an effective demagnetizing field in the perpendicular direction. Furthermore, the perpendicular free layer is preferably placed on the main pole side.03-21-2013
20130070368MAGNETIC DISK DEVICE AND CONTROLLING METHOD OF HEAD - A magnetic disk device includes a head, a coil, a drive circuit, a detector, a first calculation unit, a generation unit, a first estimation unit, and a control unit. The detector detects an inter-terminal voltage across the coil. The first calculation unit calculates a back electromotive force across the coil by the use of the inter-terminal voltage. The generation unit generates a target velocity as a reference value of a velocity of the head. The first estimation unit estimates a first velocity of the head and an error of the first velocity by the use of the back electromotive force. The first estimation unit estimates a second velocity for decreasing the error. The control unit calculates a control instruction to bring the second velocity close to the target velocity.03-21-2013
20130070366MAGNETIC RECORDING HEAD WITH LOW-WEAR PROTECTIVE FILM HAVING HYDROGEN AND/OR WATER VAPOR THEREIN - According to one embodiment, a method for manufacturing a magnetic device includes forming a protective film above a structure, wherein at least one of hydrogen and water vapor are introduced into a formation chamber during formation of the protective film. In-another embodiment, a magnetic head includes at least one of: a read element, a write element, a heater element, and a resistance detector element above a substrate, conductive terminals for each of the at least one of: the read element, the write element, and the heater element, and a protective film above the at least one of: the read element, the write element, and the heater element, wherein the protective film comprises at least one of hydrogen and water vapor.03-21-2013
20130070365CURRENT SENSOR COMPRISING DIFFERENTIAL AMPLIFIER BIASED BY LEAKAGE CURRENT - A current sensor is disclosed comprising a differential amplifier including a first node, a second node, and an output. The current sensor further comprises a first resistor having a first end coupled to the first node and a second end for coupling to a transducer, and a second resistor having a first end coupled to the second node and a second end. When the second end of the second resistor is unconnected and the differential amplifier is driven with a supply voltage, the first node is biased by a first leakage current and the second node is biased by a second leakage current such that the output represents a current flowing through the transducer.03-21-2013
20130070364THIN FILM MAGNETIC HEAD AND MANUFACTURING METHOD THEREOF - A thin film magnetic head of the present invention is configured to include a main pole layer; a main pole direct junction magnetic layer that has an auxiliary pole layer and an auxiliary yoke layer, the main pole direct junction magnetic layer being directly joined to the main pole layer in a state where a recording gap layer is partially intervened near an air bearing surface (ABS) with respect to the main pole layer; and a first magnetic recording exciting coil that is buried between the auxiliary pole layer and the auxiliary yoke layer configuring the main magnetic direct junction magnetic layer with an insulating layer therebetween. Thereby, an effective magnetic path length can be shortened in order to improve the high-frequency characteristics, and furthermore, simplification of the manufacturing processes becomes possible.03-21-2013
20130050869MAGNETIC RECORDING HEAD AND MAGNETIC RECORDING/REPRODUCING APPARATUS - In high frequency magnetic assisted recording technique, a spin torque oscillator that stably oscillates at a low current and a magnetic recording head with high recording density are provided. In a magnetic recording head including an oscillator that generates a high frequency magnetic field, a spin injection layer structure of two laminated magnetic layers which are coupled to be anti-parallel is adopted. A product Ms×t of the saturated magnetization Ms and the film thickness t of the first magnetic layer close to a field generation layer is smaller than a product Ms×t of the second magnetic layer remote from the field generation layer.02-28-2013
20130088794ROBUST METRIC COMPUTATION OF LONGITUDINAL POSITION (LPOS) DATA SYMBOL DETECTION - In one embodiment, a tape drive system includes a magnetic head having a servo sensor for sensing a defined servo track of a magnetic tape and configured to read servo pulses from servo bursts of the servo track while the magnetic tape is moving past the magnetic head with the servo bursts representing an encoded data symbol, an analog-to-digital converter configured to provide a sequence of samples of the readback servo signal, a digital correlator configured to compute a correlation signal between the sequence and a reference waveform, a timing reference module configured to provide a reference timing model having interpolation instants to the digital correlator, a correlation interpolator configured to interpolate the correlation signal at the interpolation instants and compute a longitudinal position (LPOS) detection metric, and an LPOS detector configured to decode the encoded data symbol of the servo bursts using the computed LPOS detection metric.04-11-2013
20090040650PROVIDING REMOVABLE STORAGE MANAGEMENT SERVICES USING REMOVABLE STORAGE ERROR INFORMATION - Provided are a method, system, and article of manufacture for providing removable storage management services using removable storage error information. Read/write error information is obtained for at least one removable storage by interfacing with the removable storage manager. The obtained read/write error information for the at least one removable storage is processed to determine read/write error rates for the at least one removable storage. A determination is made as to whether the determined read/write error rates for the at least one removable storage exceed at least one read/write error threshold. At least one message is sent to the removable storage manager to replace the at least one removable storage having read/write error rates that exceed the at least one read/write error threshold.02-12-2009
20090091855METHOD FOR IMPROVED INSITU SPIRAL WRITING - A system includes a first current generator generating a first current to bias an actuator arm against a spring when a control signal is received and discontinues said first current to release said spring and accelerate said actuator arm when servo signals are generated. A second current generator generates a second current biasing said actuator arm away from said spring when said first current is discontinued.04-09-2009
20130057978MAGNETIC RECORDING REPRODUCING APPARATUS AND MAGNETIC RECORDING MEDIUM - In an information recording area of a disc-shaped magnetic recording medium, recording columns adjacent to each other relative to a radial direction are formed so as to partially overlap with each other in the radial direction. Each recording column has an overlapping portion which partially overlaps with either of the adjacent recording columns in the radial direction, and a non-overlapping portion which does not overlap with any of the recording columns in the radial direction.03-07-2013
20130057977MAGNETIC RECORDING REPRODUCING APPARATUS AND MAGNETIC RECORDING MEDIUM - In information recording areas of a disc-shaped magnetic recording medium, recording columns adjacent to each other relative to a radial direction are formed to partially overlap with each other in the radial direction. A first recording and a second recording are selectively performed. In the first recording, a first recording column, a second recording column (the outer adjacent recording column of the first recording column) and a third recording column (the outer adjacent recording column of the second recording column) are formed so that the radial positions of the inner and outer circumferential edges of the first recording column, those of a second recording column, and those of a third recording column satisfy R03-07-2013
20090279199Method and apparatus for reducing slider contact probability in a load-unload (LUL) hard disk drive - A Load-UnLoad hard disk drive (HDD) with a roll static angle between the slider and the rotating disk surface of at most zero degrees is disclosed. Put another way, the slider contact with the disk surface during loading is reduced when the outer edge is not nearer than the inner edge of the slider to the disk surface. A head gimbal assembly holding a slider so that the slider will have a roll static angle of at most zero degrees in the HDD. A head stack assembly including at least one of these head gimbal assemblies. Operating a HDD where the slider is loaded onto the rotating disk surface at a roll static angle that is at most zero degrees.11-12-2009
20120307399METHOD AND SYSTEM FOR PROVIDING TAPE-FORMAT COMPATIBILITY BETWEEN VARIOUS TYPES OF TAPE HEADS - Certain embodiments of the present invention are directed to magnetic-tape drives that employ data-set-multiplexing magnetic-tape formats in order to achieve compatibility in magnetic-tape formats with respect to a variety of different magnetic-tape-drive tape-head configurations and dimensions. While previous and current magnetic-tape drives employ magnetic-tape formats that feature linear sequences of data sets along the tracks that are read or written during a single pass, or wrap, magnetic-tape drives of the present invention feature magnetic tape that contains data formatted according to a data-set-multiplexing magnetic-tape format, the data-set-multiplexing magnetic-tape format including, for each multiple-track wrap within a band, two or more parallel sequences of data sets written to the multiple tracks of the multiple-track wrap.12-06-2012
20120307395PERPENDICULAR MAGNETIC RECORDING MEDIUM WITH AN INVERTED Hk STRUCTURE - According to one embodiment, a perpendicular magnetic recording medium includes a first granular recording layer characterized by a magnetic anisotropy Ku12-06-2012
20090296263INFORMATION STORAGE APPARATUS - An information storage apparatus includes a disc-shaped recording medium in which control marks aligned in a predetermined rule are recorded, a head contacting or approaching a recording medium surface to reproduce/record information of the recording medium and detecting the control marks, a head driving section holding the head to move the head in a direction of coming near or away to/from a recording medium rotation center, a driving force control section controlling a driving force for head driving section, a driving time control section controlling a driving time for the head driving section using an interval of the detection of the plural control marks as a time unit, and a driving force correcting section obtaining a difference between an ideal interval based on the rule of the control marks and an actual interval of the control marks to correct the control of the driving force based on the difference.12-03-2009
20090128946DISCONTINUOUS MODE BACK EMF MEASUREMENT - A terminal voltage of an actuator motor is measured while the actuator motor is in a high impedance state. An internal voltage of the actuator motor is measured, and a back-EMF voltage of the actuator motor is estimated in response to the terminal voltage of the actuator motor and the internal voltage of the actuator motor. A drive current supplied to the actuator motor is controlled in response to the estimated back-EMF.05-21-2009
20100128383DISK DRIVE AND METHOD FOR CONTROLLING CLEARANCE IN THE DISK DRIVE - A disk drive. The disk drive includes a disk configured to store data, a slider configured to fly in proximity to the disk, and a magnetic-recording head on the slider configured to access the disk. The disk drive also includes a moving mechanism configured to support and to move the head-slider, an adjustment portion configured to adjust clearance between the magnetic-recording head and the disk, and a controller configured to control the adjustment portion to control the clearance. The controller is configured to perform clearance control in a first mode in an operation selected from the group consisting of reading user data and writing user data according to a change in fly height of the slider after a load operation, and subsequently is configured to perform clearance control in a second mode in an operation selected from the group consisting of reading user data and writing user data.05-27-2010
20110013311MAGNETIC RECORDING MEDIUM, METHOD FOR PRODUCING MAGNETIC RECORDING MEDIUM , AND MAGNETIC RECORDING/ REPRODUCING APPARATUS - A magnetic recording medium comprising a magnetic layer having a magnetic recording pattern comprising elevations constituting magnetic recording regions and depressions constituting boundary regions for partitioning the magnetic recording regions, and a continuous protective carbon overcoat on the magnetic layer, characterized in that portions of the carbon overcoat located on the magnetic recording regions-constituting elevations of the magnetic layer are thicker than portions of the carbon overcoat located on the boundary regions-constituting depressions of the magnetic layer. The protective carbon overcoat is formed by a CVD method. The boundary regions-constituting depressions are preferably subjected to exposure to plasma, and have modified magnetic characteristics. The magnetic recording regions exhibit high corrosion resistance and the magnetic recording medium has enhanced environmental resistance.01-20-2011
20110013310RECORDING MEDIUM DRIVING DEVICE AND MAGNETIC RECORDING MEDIUM, AND METHOD FOR CONTROLLING FLYING HEIGHT OF HEAD ELEMENT - According to one embodiment, a recording medium driving device includes: a recording medium including a plurality of groove regions and land regions, wherein each of the groove regions is formed in a groove formed on top surface of the recording medium and having an arrangement of a magnetic domain formed for each bit, and each of the land regions forms a flat surface on the top surface of the recording medium and in between a pair of the groove regions in adjacency; a head slider disposed to face the top surface of the recording medium; a head element mounted on the head slider; a heater mounted on the head slider and configured to cause a projection in the head element by heat; and a control circuit configured to cause the projection to contact with the land region at time of performing zero calibration for the projection.01-20-2011
20110013309CONTACT TYPE THIN FILM MAGNETIC HEAD WITH HEATERS FOR DISTANCE CONTROL - A contact type thin film magnetic head and method of using the same are provided. The contact type thin film magnetic head comprises a head element that is provided on a disk-facing surface of a slider, a magnetic disk, and heating elements disposed in a plane position different from that of the head element. A protective layer covers the heating elements and the head element. The heating elements and the protecting layer are formed on the disk-facing surface of the slider. The protective layer protrudes further toward the magnetic disk than the head element.01-20-2011
20090268336DATA STORAGE DEVICE AND ADJACENT TRACK REWRITE PROCESSING METHOD - A data storage device, that stores write data by a head, rewrites data on an adjacent track at a timing which is different from write retry of detecting a head off track when data may be written to an adjacent track. When an off track error, which affects data on an adjacent track, is generated by a write command, rewrite processing of this write command is not executed immediately, but a rewrite request including information on the track to be rewritten and the shift amount of the off track is held. And the rewrite request being held is executed at a timing which is different from the write retry. So rewrite processing can be executed after vibration, which caused the off track, stops, and the generation of an off track error during rewrite processing and the generation of further off track writing can be prevented.10-29-2009
20130063837MAGNETIC RECORDING HEAD, MANUFACTURING METHOD THEREOF, AND MAGNETIC DISK DEVICE - A magnetic recording head used for microwave-assisted magnetic recording includes: a main pole; a spin torque oscillator provided on the main pole, including a high-speed rotating magnetization layer in which the magnetization is rapidly rotated by a spin torque; a trailing shield provided on the spin torque oscillator; and a sub pole magnetically coupled to the trailing shield provided in a medium-facing surface, extending in a vertical direction to the medium-facing surface. Then, a non-magnetic electrode is provided on the outside of a trailing gap in which the spin torque oscillator is provided with respect to a magnetic material of the main pole, the trailing shield, or the sub pole, to prevent the line resistance variation due to the AMR effect or the eddy current. Thus, the variation of the current flowing to the spin torque oscillator can be controlled to achieve stable oscillation.03-14-2013
20130163114BASE ASSEMBLY FOR MOTOR AND HARD DISK DRIVE INCLUDING THE SAME - There is provided a base assembly for a motor, including: a base for a motor; a magnet mounted in the base to provide a driving force to a magnetic head; and a magnet insertion part having the magnet inserted therein and formed to penetrate through the base so as to restrict a movement of the magnet.06-27-2013
20130163115METHOD AND APPARATUS FOR SERVO PATTERN WRITING - Disclosed are servo pattern writing methods and apparatuses for performing the same. In one example, a method may include providing a plurality of disks having reference servo patterns written thereon; writing align patterns aligned with each other in a horizontal direction of the disk surface, on the plurality of disks, using a reference servo pattern of one of the plurality of disks; and writing a final servo pattern on each disk, using the align pattern written on each disk.06-27-2013
20130163110BALANCED EMBEDDED CONTACT SENSOR WITH LOW NOISE ARCHITECTURE - Approaches for a hard-disk drive (HDD) having a balanced resistive temperature detector (RTD). A HDD includes a head slider comprising a single RTD. A read/write IC comprises a balance resistor having the same resistance as the single RTD when the head slider is not in physical contact with the disk. The same amount of current flows through the single RTD and the balance resistor except when the head slider is in physical contact with the disk. Detecting a voltage change across the single RTD enables physical contact between the head slider and the disk to be accurately detected using a circuit with low noise. Alternately, the head slider may include two RTDs connected in sequence, and the balance resistor may possess the same resistance as the two RTDs. The two RTDs may vary inversely with environmental changes to avoid the need to recalibrate the balance resistor after any environmental change.06-27-2013
20130163112BASE ASSEMBLY AND RECORDING DISK DRIVING DEVICE INCLUDING THE SAME - There is provided a base assembly including: a bracket device connected to a head assembly in order to drive the head assembly for reading information from a disk and including an elastic member provided on one surface thereof, the elastic member having a terminal disposed in an inner portion thereof and connected to a main circuit board; and a press base formed by press processing and having an opening part into which the elastic member is inserted, wherein the press base includes an elastic support part forming the opening part and extended in a direction into which the bracket device is inserted to thereby increase a contact area with the elastic member.06-27-2013
20130163113BASE FOR MOTOR AND HARD DISK DRIVE INCLUDING THE SAME - There are provided a base for a motor and a hard disk drive including the same. The base for a motor includes a base body having a disk disposed thereon; and a fixing part formed on the base body and slidably fitted in a female rail mounted on at least one side of a connector part mounted on a substrate to fix the base body to the substrate to which power is applied.06-27-2013
20090237829INFORMATION RECORDING MEDIUM - An information recording medium has a substrate, first recording dots, and second recording dots. The first recording dots are arranged in an array circumferentially in accordance with a predetermined regulation at mutual intervals in accordance with the regulation at a position in accordance with the regulation, and are used to magnetically record information. The second recording dots are arranged in an array circumferentially in accordance with the regulation at mutual intervals in accordance with the regulation. In the second recording dots, plural kinds of positions having different deviation amounts from the position in accordance with the regulation appear in one round of the array. The second recording dots are also used to magnetically record information.09-24-2009
20090237831STORAGE DEVICE, MAGNETIC CIRCUIT, AND ACTUATOR - When impact occurs, a magnetic disk device detects the impact, being transmitted to a head, on an actuator located in a route from an impact source to the head. Upon detection of the impact, the magnetic disk device stops data write operation. Specifically, before the impact is transmitted to the head and errors occur in the write operation, the magnetic disk device detects the impact on the actuator located in the route from the impact source to the head, and stops the write operation.09-24-2009
20090237830METHOD OF CONTROLLING FLYING HEIGHT OF HEAD SLIDER AND INFORMATION STORAGE APPARATUS - One aspect of the embodiments is related to a method of controlling a flying height of a head slider. The method includes the steps of measuring a first correlation value between an air pressure and a heating element sensitivity of the head slider, measuring a second correlation value between the air pressure and the flying height of the head slider, calculating a reference heating-element sensitivity at normal air pressure from the first correlation value, measuring a heating element sensitivity of the heating element when the head slider is lifted, calculating the difference between the heating element sensitivity and the reference heating-element sensitivity to calculate an amount of variation in air pressure from the first correlation value, and calculating an amount of variation in the flying height of the head slider from the amount of variation in air pressure and the second correlation value and controlling the heating element.09-24-2009
20090231752MAGNETIC TAPE DRIVING APPARATUS - A magnetic tape driving apparatus includes a magnetic head 09-17-2009
20090027798IMPACT PROTECTION FOR A RETRACTABLE CONTROL OBJECT - Various embodiments of the present invention are generally directed to protecting a device from damage due to an impact event at the conclusion of a free fall condition through the use of a biasing signal that maintains a retention force until the impact event is completed.01-29-2009
20090009904Method for forming servo pattern and magnetic disk drive - Embodiments of the present invention provide a method of forming an initial servo-pattern for self servowrite, insusceptible to constraints of an output resolution of a driver circuit for driving an actuator, and a dynamic range. According to one embodiment, a cluster pattern made up of pattern blocks, each including a burst pattern, is written by use of a write element by pressing a head-support mechanism to a crash-stop, and a pattern block is newly written with a read element in states of being positioned at an inner peripheral side edge of the cluster pattern, an outer peripheral side edge thereof, and the center of two burst patterns included in the cluster pattern, respectively, thereby increasing a width of the cluster patterns in stages, so that an initial servo pattern for use in a propagation action is formed.01-08-2009
20090009903METHOD OF INCREASING RECORDING DENSITY OF HARD DISC DRIVE AND CONTROLLING DEVICE THEREOF - Provided is a method of increasing recording density and a control apparatus for increasing the recording density. The method includes applying a recording current corresponding to a recording signal to a magnetic head of a hard disc drive (HDD), and limiting a current value being applied to the magnetic head to a critical value when the recording current reaches the critical value. In the method, a rising time is reduced by using an overshoot recording current and the recording current is limited to a critical value when an actual recording current reaches the critical value. Thus, write track widths (WTWs) can be reduced at a low recording frequency, thereby increasing tracks per inch (TPI).01-08-2009
20120113543MAGNETIC HEAD AND MAGNETIC RECORDING/REPRODUCTION APPARATUS USING THE SAME - A magnetic recording head enabling both enhancement of a strength of a magnetic field from a main pole and provision of narrow-track recording to achieve a high recording density in a high-frequency magnetic field-assisted recording method is provided. An oscillator 05-10-2012
20120113542OSCILLATOR IN WHICH POLARITY IS CHANGED AT HIGH SPEED, MAGNETIC HEAD FOR MAMR AND FAST DATA TRANSFER RATE HDD - The present invention provides a magnetic recording head and a magnetic recording device that realize information transfer speed exceeding 1 Gbit/s in microwave assisted magnetic recording applied to a magnetic recording device having recording density exceeding 1 Tbit/in05-10-2012
20100085657Control Method for Magnetic Disk Device, Magnetic Disk Device, and Magnetic Disk - According to one embodiment, a control method for a magnetic disk device includes writing data by varying a phase of the array period of the plurality of magnetic elements or a phase of the time period of the recording signal in one section of the track from a corresponding phase in another section of the track, reading a reproduction signal from the track, and determining a phase shift between the array period of the plurality of magnetic elements and the time period of the recording signal, based on a reproduction signal read from the one section and a reproduction signal read from the other section. In another embodiment, a magnetic disk includes a track in which magnetic elements are magnetically separated and arranged in an array period, and a phase of the array period in one section is different from a phase in another section of the track.04-08-2010
20130163111MAGNETIC DATA RECORDING SYSTEM WITH IMPROVED SERVO CAPABILITY FOR BIT PATTERNED RECORDING - A magnetic data recording system wherein the wherein adjacent track interference during writing is avoided by modulating the size of a write bubble on the magnetic media in response to a position error signal. If the position error signal indicates that the magnetic head is off-track, circuitry within the magnetic data recording system adjusts the size of the write bubble temporarily to prevent the write bubble from encroaching on a neighboring data track. This adjustment of the write bubble can be accomplished by adjusting power to the write head. Adjustment of the write bubble can also be achieved by adjusting power to a magnetic oscillator in a microwave assisted magnetic recording system (MAMR) or adjusting power to a heating element in a thermally assisted magnetic recording system.06-27-2013
20080297941DATA RECORDING APPARATUS AND DATA RECORDING METHOD - A data recording apparatus of the present invention includes a head that records data signals by magnetizing a magnetic tape 12-04-2008
20120236433MULTI-CHANNEL TAPE HEAD HAVING ASYMMETRIC CHANNEL ARRAYS - In one general embodiment, a magnetic head comprises an inner module comprising an array of data readers; and first and second outer modules flanking the inner module. The outer modules are identical, each outer module comprising an array of data writers. A number of active data writers in each outer module is less than a number of active data readers in the inner module. For the first outer module, one of the active data writers is aligned with one of the data reader positioned towards a first end of the inner module array in a direction generally parallel to the path of tape travel thereacross. For the second outer module, one of the active data writers is aligned with one of the data readers positioned towards a second end of the inner module array in the direction generally parallel to the path of tape travel thereacross.09-20-2012
20120236432MAGNETIC DISK DRIVE AND CONTROL METHOD - According to one embodiment, a magnetic disk device includes: a magnetic disk having data spiral tracks extending from an outer circumference towards an inner circumference or from an inner circumference towards an outer circumference; a head configured to read data recorded in the data tracks of the magnetic disk that is rotating and to write data to the data tracks; and a controller configured to control the head to follow a predetermined data track in units obtained by subtracting a seek time required for the head to seek the predetermined data track from a rotation period.09-20-2012
20110188151THIN-FILM MAGNETIC HEAD HAVING A MAGNETIC POLE FORMED OF A PLATING FILM - A magnetic pole of a magnetic head includes a narrow and a wide portion, and is formed of a plating film. An electrode film forms the plating film, and is provided only under at least a part of the wide portion. A manufacturing method for the magnetic head includes: forming a plating-film-accommodating layer with an accommodating groove; forming the electrode film in part of the accommodating groove; and forming the plating film in the accommodating groove by plating using the electrode film. The accommodating groove includes a narrow and a wide groove portion for accommodating the narrow and wide portions, respectively. The electrode film is provided in at least a part of the wide groove portion. In the step of forming the plating film, the plating film grows from the surface of the electrode film, and the narrow groove portion is filled with a part of the plating film.08-04-2011
20100020433MAGNETIC DISK APPARATUS AND MAGNETIC DISK ACCESS CONTROL METHOD - A magnetic disk apparatus includes a magnetic disk, a magnetic head, a reverse-pulse detector, and a re-magnetizer. The magnetic disk includes a data recording area and a servo-pattern area. The magnetic regions of the servo-pattern area have been pre-magnetized in the same direction or pre-magnetizing direction. The magnetic head is arranged to reciprocate radially of the magnetic disk. The reverse-pulse detector is provided for reading the servo-pattern area with the magnetic head before data recording or reproducing with respect to the data recording area is performed. The reverse-pulse detector detects, from servo reproduction signal pulses, reverse pulses corresponding to the reversal of magnetization direction relative to the pre-magnetizing direction. The re-magnetizer causes the magnetic head to perform the re-magnetizing of the magnetic regions in the servo-pattern area when the count of reverse pulses is not smaller than a threshold number.01-28-2010
20110069409METHOD AND APPARATUS FOR FORMING SERVO PATTERNS ON A MAGNETIC-RECORDING DISK - A method for forming servo patterns on a magnetic-recording disk. The method includes moving a magnetic-recording head in an opposite direction to a pattern development direction, when there is a faulty servo pattern. The method also includes positioning a write element of the magnetic recording head on a track of the faulty servo pattern and forming a reserve servo pattern at a different circumferential location from that of the faulty servo pattern. The method includes moving the magnetic-recording head in the pattern development direction. The method further includes positioning the read element on the track of the faulty servo pattern and forming a new servo pattern in the pattern development direction at the circumferential location of the faulty servo pattern on a track disposed between the track of the faulty servo pattern and an outside diameter of the magnetic-recording disk, based on data read from the reserve servo pattern.03-24-2011
20100328810DISK DRIVE AND SERVO-CONTROL METHOD THEREFOR - A disk drive. The disk drive includes a head, an actuator, and a controller. The head accesses a disk. The actuator is configured to support the head and to move the head by action of a voice-coil motor in a substantially radial direction of the disk. The controller is also configured to perform servo control of the actuator by using servo data read out by the head. The controller includes at least one of a plurality of notch filters having a fixed center frequency inserted in a servo-control loop. The controller is configured to increase an attenuation rate by at least one of the plurality of notch filters having the fixed center frequency at a designated frequency, when a target position of the head is at a position selected from the group consisting of a position outside of a specified region and a position within the specified region.12-30-2010
20090195911MAGNETIC RECORDING DEVICE - A magnetic recording device includes a patterned media magnetic recording medium where multiple tracks are arranged for radial direction in a concentric manner, the tracks each being formed by arranging multiple recording dots. The recording dots are each made of an isolated magnetic material and arranged in a rotational direction. The magnetic recording device further includes a magnetic head. The magnetic head includes: a main magnetic pole that faces the magnetic recording medium; a magnetic field generation coil that generates magnetic field to be transmitted to the magnetic recording medium through the main magnetic pole; a return yoke that receives the magnetic flux transmitted to the magnetic recording medium from the main magnetic pole and returns the magnetic flux thus received to the magnetic field generation coil; and a search coil that detects a change in magnetic flux passing through the return yoke.08-06-2009
20100202082Systems and Methods for Variable Fly Height Measurement - Various embodiments of the present invention provide systems and methods for determining fly height. For example, a system for fly height determination is disclosed that includes a head assembly disposed in relation to a storage medium, a write channel, and a read circuit. The read circuit is operable to receive information from both the head assembly and the write channel. A frequency determination circuit is included that is operable to receive a first signal from the read circuit corresponding to information received from the write channel and to provide a first fundamental frequency and a first higher order frequency based on the first signal, and the frequency determination circuit is operable to receive a second signal from the read circuit corresponding to information received from the head assembly channel and to provide a second fundamental frequency and a second higher order frequency based on the second signal. A compensation variable calculation module is included that is operable to divide the first fundamental frequency by the first higher order harmonic to yield a compensation variable. A fly height calculation module is included that is operable to divide the second fundamental frequency by the second higher order harmonic and the compensation variable to yield an indication of a distance between the head assembly and the storage medium.08-12-2010
20110109986CONTROL SYSTEM AND METHOD FOR LOADING ACTUATOR ARM OF ROTATING STORAGE DEVICE - A system includes a control module configured to generate a first signal to control a speed of an actuator arm of a rotating storage device. An estimating module includes a first filter configured to generate a first filtered output based on the first signal. A second filter is configured to generate a second filtered output based on the speed of the actuator arm. The estimating module is configured to estimate a force to move the actuator arm based on (i) the first filtered output and (ii) the second filtered output. The first filter and the second filter include infinite impulse response (IIR) filters of P05-12-2011
20110279924Patterned media for self-servowriting integrated servo fields - Pre-patterned discrete track media for self-servo writing are described. Embodiments include land and groove patterns for two or more Integrated Servo sequence fields for each servo sector in which one of the Integrated Servo sequence fields is aligned with the data track and a second sequence is offset by one-half of a track width. The lands and grooves between the Integrated Servo sequence fields are preferably the same width as those between the data tracks to facilitate planarization. Alternative embodiments include a sync feature for each servo sector formed by a selected groove and/or land pattern as a marker for the start of the servo fields. Alternative embodiments include a bootstrap zone with servo patterns that are readable when DC-magnetized. Described methods of self-servowriting include ways to adapt to eccentricity and non-circularity of pre-patterned discrete tracks with respect to the head paths.11-17-2011
20110279923MAGNETORESISTIVE ELEMENT HAVING A PAIR OF SIDE SHIELDS - An MR element includes an MR stack disposed between first and second main shield portions, and a pair of side shields disposed on opposite sides of the MR stack in the track width direction. The first main shield portion includes a first exchange coupling shield layer that is exchange-coupled to a first antiferromagnetic layer. The second main shield portion includes a second exchange coupling shield layer that is exchange-coupled to a second antiferromagnetic layer. The MR stack includes a spacer layer, and first and second free layers with the spacer layer therebetween. The direction of magnetization of the first free layer is controlled by the first exchange coupling shield layer. The direction of magnetization of the second free layer is controlled by the second exchange coupling shield layer. Each side shield includes at least one shield-coupling magnetic layer that is in contact with and magnetically coupled to one of the first and second exchange coupling shield layers.11-17-2011
20110134563MAGNETORESISTIVE EFFECT HEAD HAVING A MULTILAYERED PINNED LAYER OR FREE LAYER AND SYSTEMS THEREOF - According to one embodiment, a magnetoresistive effect head includes a magnetically pinned layer having a direction of magnetization that is pinned, a free magnetic layer positioned above the magnetically pinned layer, the free magnetic layer having a direction of magnetization that is free to vary, and a barrier layer comprising an insulator positioned between the magnetically pinned layer and the free magnetic layer, wherein at least one of the magnetically pinned layer and the free magnetic layer has a layered structure, the layered structure including a crystal layer comprising one of: a CoFe magnetic layer or a CoFeB magnetic layer and an amorphous magnetic layer comprising CoFeB and an element selected from: Ta, Hf, Zr, and Nb, wherein the crystal layer is positioned closer to a tunnel barrier layer than the amorphous magnetic layer. In another embodiment, a magnetic data storage system includes the magnetoresistive effect head described above.06-09-2011
20090310246HEAD FLYING HEIGHT CONTROL METHOD, WRITE CURRENT VALUE DETERMINING METHOD, AND STORAGE DEVICE - A head flying height control method includes the steps of: detecting contact of a head having a heater with a corresponding storage medium, and associating the amount of heat generated by the heater when the contact is detected with a situation where the flying height of the head is zero; measuring at least one type of characteristics that are the saturation characteristics of the read margin of data written on the storage medium with the head, and the saturation characteristics of the electromagnetic conversion characteristics of the head, the measuring step being carried out every time the flying height of the head is varied, with a reference being the situation where the flying height of the head is zero, the current used for writing the data being a parameter in the saturation characteristics; and adjusting the flying height of the head, based on the measurement result of the measuring step.12-17-2009
20100014185POSITION CONTROL APPARATUS AND DISK APPARATUS USING THE SAME - According to one embodiment, a position control apparatus includes: a digital control module that performs position control including disturbance adaptive control with a predetermined sampling period using a control constant, in accordance with a position error between a target position and a current position of the object; and a table that stores the control constant corresponding to a value of sin(ωT) or cos(ωT), wherein the digital control module is configured to determine a control value of the actuator in accordance with the position error, calculates the value of sin(ωT) or cos(ωT) according to an adaptive law from a signal based on the position error, reads the corresponding control constant from the table in accordance with the calculated value of sin(ωT) or cos(ωT), and updates the control constant, to perform the position control including the disturbance adaptive control.01-21-2010
20090316292MAGNETORESISTIVE HEADS AND MAGNETIC RECORDING DEVICE - A magnetoresistive head is provided with high reliability and produced at a high yield rate. The magnetoresistive head includes a lower magnetic shield layer, an upper magnetic shield layer, a magnetoresistive effect film, and means for causing a current to flow in the direction of the thickness of the magnetoresistive effect film. The magnetoresistive effect film is provided between the lower magnetic shield layer and the upper magnetic shield layer. The magnetoresistive effect film is composed of a fixed layer, a non-magnetic layer, an insulating barrier layer and a free layer. The four layers of the magnetoresistive effect film are formed in this order. The insulating barrier layer is an oxide layer containing at least one of titanium and nickel.12-24-2009
20110286130ENERGY-SAVING OPERATION OF A STORAGE DEVICE - A computer implemented method is disclosed, for energy-saving operation of a storage device with a read/write head. The method includes monitoring workload of the storage device, calculating current mean workload and adjusting seek speed of the read/write head of the storage device to one of a plurality seek speeds depending on the calculated current mean workload. The step of adjusting the seek speed of the read/write head includes adjusting the seek speed of the read/write head to be a first seek speed if the calculated current mean workload is below a first threshold, adjusting the seek speed of the read/write head to be a second seek speed if the calculated current mean workload is between the first threshold and a second threshold, and adjusting the seek speed of the read/write head to be the first seek speed if the calculated current mean workload is greater than the second threshold. A computer program product and a data processing system are also disclosed.11-24-2011
20120105999INTEGRATED TOUCH-DOWN PAD AND TOUCH-DOWN SENSOR - In one general embodiment, a magnetic head includes a touch-down pad, comprising at least one shielding element positioned between a leading edge of a main magnetic pole and a trailing edge of a lower return pole; an embedded contact sensor (ECS) in an electrically isolating layer, the ECS positioned near an ABS side of the magnetic head and between the leading edge of the main magnetic pole and the trailing edge of the lower return pole; and a first thermal fly-height control (TFC) element positioned away from the ABS side of the magnetic head. Additional systems and methods are also presented.05-03-2012
20110141616MAGNETIC RECORDING HEAD AND MAGNETIC DISK STORAGE DEVICE - In one embodiment, a magnetic recording head includes a main magnetic pole adapted for generating a magnetic field for recording information on a magnetic disk, a magnetic shield member adapted for suppressing spreading of a magnetic field output from the main magnetic pole through a non-magnetic insulation member, a side top gap, a side bottom gap, and a trailing gap. The side top gap is less than two times the trailing gap, the side bottom gap is larger than the side top gap, and the magnetic shield member is positioned on a sliding surface of the magnetic recording head and includes a trailing portion positioned adjacent the trailing gap in the trailing direction and at least one side portion positioned adjacent the side bottom gap in the cross-track direction. Other heads and systems are also presented according to various embodiments.06-16-2011
20110299189ACTIVE HEAD SLIDER HAVING PIEZOELECTRIC AND THERMAL ACTUATORS - An active head slider for a use in a Hard Disk drive having first and second actuators. The first actuator deforming a portion of a slider body that includes a read/write head to reduce the flying height of the portion over a disk. The second actuator forming a protrusion in a bottom surface of the slider body that includes an end of the read/write head to further reduce the flying height of the read/write head. Preferably, the first actuator is a piezoelectric actuator and the second actuator is one or more thermo actuators.12-08-2011
20110299192MAGNETIC RECORDING HEAD AND MAGNETIC RECORDING APPARATUS - An example magnetic recording head includes: a main magnetic pole; a laminated body; and a pair of electrodes. The laminated body includes a first magnetic layer having a coercivity lower than magnetic field applied by the main magnetic pole, a second magnetic layer having a coercivity lower than the magnetic field applied by the main magnetic pole, and an intermediate layer provided between the first magnetic layer and the second magnetic layer. The pair of electrodes is operable to pass a current through the laminated body.12-08-2011
20110299190DETECTING TOUCH DOWN AND/OR ASSESSING QUALITY IN A HARD DISK DRIVE - This application discloses a hard disk drive and a control circuit that are configured to determine touchdown by determining the SAGC for a track, removing the repeatable component of the SAGC to create the non-repeatable component and determining an indication of clearance irregularity and/or touch down when the standard deviation of the non-repeatable component spikes. These operations may create a defect map and/or a Flying height On Demand (FOD) control table in or for the hard disk drive as products of operating the hard disk drive.12-08-2011
20110299191Electrical current as probe for modulation at head-disk interface - A system and method for measuring the modulation between a magnetic head and a magnetic storage medium, such as a disk, is disclosed. A magnetic read/write head is positioned above a magnetic storage medium at a given flying height. The magnetic read/write head reads a signal from the magnetic storage medium. A tester measures an alternating electric current between the magnetic read/write head through the slider and the magnetic storage medium. A computer may then calculate the modulation by the magnetic read/write head based on the alternating electric current. A DC voltage to the head may be applied to lower the flying height of the magnetic head.12-08-2011
20110141610WRITE SYNCHRONIZATION IN PATTERNED MAGNETIC MEDIA - Systems and methods for synchronizing write signals are disclosed. In one embodiment, a compensation system is implemented within a disk drive that receives a synchronization signal read from a patterned magnetic disk by a read head. The compensation system processes the synchronization signal to compensate for noise sensed by the read head while a write head writes to the disk based on a write signal. The adjustment module is operable to adjust the write signal based on the processed synchronization signal so that the write signal is synchronized to the pattern on the disk.06-16-2011
20090290250MAGNETIC RECORDING MEDIUM, METHOD FOR PRODUCTION THEREOF AND MAGNETIC RECORDING AND REPRODUCING DEVICE - A discrete track-type magnetic recording medium (11-26-2009
20110292540Systems and Methods for Protecting Hard Disk Drives - A modified hard disk drive (HDD) state is provided. The modified HDD state corresponds to a state wherein the heads of a hard disk drive assembly are parked as a baseline setting, but permitted to float over the platters for completing requests on a limited basis. This prioritizes HHD protection in certain contexts.12-01-2011
20080266704Hard disk drive, method of controlling flying height of magnetic head thereof, and recording medium containing computer program thereon - A method of controlling a flying height of a magnetic head of a hard disk drive includes calculating a corrected flying on demand (FOD) voltage to correct a difference between a measured flying height measured by applying a burn-in FOD voltage corresponding to a target flying height and a burn-in flying height in a reference FOD voltage profile corresponding to the burn-in FOD voltage, using the reference FOD voltage profile, in the reference FOD voltage profile that is a profile of a second signal for calculating the flying height of the magnetic head with respect to a first signal for calculating an FOD voltage that allows an end of the magnetic head to thermally expand and protrude when applied to a heater included in the magnetic head, and applying an applied FOD voltage obtained by applying the corrected FOD voltage, to the burn-in FOD voltage, to control the flying height of the magnetic head. Thus, the reliability in the read/write operation can be improved and performance of the hard disk drive can be improved.10-30-2008
20100061009MAGNETIC DISK DEVICE - A magnetic disk device includes a magnetic storage medium including a surface coated with a first coating layer material having an elementary composition, and a magnetic head including a surface coated with a second coating layer material having the elementary composition.03-11-2010
20080239549Algorithm decoupling altitude effect from temperature/humidity sensor - A hard disk drive that calculates an environmental condition, such as altitude, without a sensor. The disk drive includes a temperature sensor that senses a disk drive temperature and a humidity sensor that senses drive humidity. A controller of the disk drive determines whether a variation in a flying height of a head is due to a change in temperature and/or a change in humidity. If not, the controller calculates a change in altitude based on a difference between an estimated variation in flying height and the actual variation in flying height. The new calculated altitude can be used to vary disk drive operating parameters such as write parameters of the heads.10-02-2008
20090097151INFORMATION STORAGE APPARATUS FOR ADJUSTING FLYING HEIGHT OF HEAD - According to an aspect of an embodiment, a storage apparatus has a motor for rotating a medium, a head for writing data into or reading data from the medium, the head having a space control element for changing a flying height of the head over the medium and a controller for controlling the space control element so as to control the flying height of the head and the medium when writing data into or reading data from the medium, for monitoring a value of a driving current flowing through the motor, for detecting an error by comparison of data written into the medium and data read out from the medium, and for changing the flying height of the head by controlling the space control element in accordance with the monitored driving current when an error is detected.04-16-2009
20100033867MAGNETIC STORAGE MEDIUM AND MAGNETIC RECORDING DEVICE - A patterned media type magnetic storage medium has separated magnetic dots formed a data area having a first magnetic dots and a servo area. The micro position detection portion in the servo area is constructed with first and second dot arrays having a different number of second magnetic dots in the circumference direction and face with the center line that the first magnetic dots of the data area in the magnetic storage medium are disposed, as the axis. The area of the magnetic dot constituting the micro position detection portion of the servo area is small, so the coercive force of the servo area increases. The frequency is changed depending on the number of magnetic dots, and the phase is changed depending on the position of the magnetic dot array in the radius direction with the center line as an axis.02-11-2010
20090195913MAGNETIC DISK APPARATUS AND METHOD FOR CONTROLLING MAGNETIC HEAD - A magnetic disk apparatus includes: a driving section for moving a magnetic head recoding and reproducing information in a magnetic disk; and a controller for controlling the driving section. The controller includes: a position-error feedback control system having an integrator and a phase lead compensator and obtaining a position command based on difference between target position and detection position of the magnetic head to perform feedback control of the driving section; and a two-freedom-degree control system inputting a target move distance of the magnetic head and outputting a current command to the driving section by using a mathematic model of the driving section. The controller providing the driving section with an output of the integrator and therewith updating the mathematical model by using an output of the phase lead compensator, in each of the times of positioning control and seek of the magnetic head.08-06-2009
20090195910STORAGE DEVICE AND METHOD OF CONTROLLING SPINDLE MOTOR OF STORAGE DEVICE - In a storage device, before activating a spindle motor (SPM) or continuously from activation until the SPM is stabilized at a target number of rotations, a voltage and temperature monitoring unit monitors the temperature in a disk enclosure unit and the voltage to be applied to an SPM driver. A current-amount limiting value calculating unit calculates an optimum current-amount limiting value not exceeding a rated current of the SPM driver, and a motor controlling unit controls the SPM driver and changes the current to be applied to the SPM so that the current does not exceed this optimum current-amount limiting value.08-06-2009
20090195908Method and apparatus for vibration damping of a suspended media read/write head - A method of controlling a head for a recording medium includes determining that the head is in an inoperative state, and activating a damping arrangement in response to the determination that the head is inoperative. A movement of the head while the head is inoperative is sensed. The damping arrangement is used in response to the sensing step to exert a force upon the head to thereby damp the movement, a magnitude of the force being dependent upon a parameter of the movement.08-06-2009
20090296258ELECTROMAGNETIC FIELD DETECTING ELEMENT AND DEVICE USING SAME - An electromagnetic field detecting element 12-03-2009
20100091401HEAD SLIDER AND STORAGE MEDIUM DRIVING DEVICE - According to one embodiment, a head slider, includes: a slider body; an insulating nonmagnetic film configured to be laminated on an air outflow side end face of the slider body; a magnetoresistive effect film configured to be buried in the nonmagnetic film; first and second wiring patterns configured to be buried in the nonmagnetic film and connected to the magnetoresistive effect film; a third wiring pattern configured to be buried in the nonmagnetic film and connected to the first and second wiring pattern in parallel to the magnetoresistive effect film; and a switch element configured to be buried in the nonmagnetic film and change conductivity of the third wiring pattern between conduction and non-conduction.04-15-2010
20100007984RECORDING MEDIUM, RECORDING APPARATUS, REPRODUCING APPARATUS, AND REPRODUCING METHOD - Provided is a recording medium onto which a plurality of tracks that constitute a unit as one unit of signal processing for reproducing data are recorded, each of the plurality of tracks being recorded with at least data and, as a preamble necessary for controlling the reproduction of the data, a separation pattern necessary for detecting a positional relationship between a reproducing head and the plurality of tracks in a track width direction and synchronization patterns for synchronization processing, the synchronization patterns being recorded in front and rear of the separation pattern in a running direction of the plurality of tracks.01-14-2010
20100110579Apparatus, System and Method for Magnetic Recording - An apparatus, system and method for magnetic recording are disclosed. In at least one embodiment, the apparatus includes a first portion of a first magnetic medium having a first cross-sectional area, and a second portion of a second magnetic medium having a second cross-sectional area. The first and second portions are joined by way of a junction that allows for at least some ferromagnetic coupling therebetween. Additionally, the first and second cross-sectional areas are of differing extent in a first dimension so that a first ledge portion of one of the first and second portions extends past a first edge of the other of the first and second portions.05-06-2010
20100226035ABS WITH LUBRICANT CONTROL TRENCHES FOR HARD DISK DRIVES - A method and apparatus for controlling lubrication in hard disk drives. Hard disk drives often include lubrication on the disks to protect the disks from incidental contact with the head slider. Embodiments of the invention include lubrication control recesses on the air bearing surface (ABS) of the head slider. The recesses reduce air stagnation on the ABS and/or store excess lubrication that migrates from the disk to the head slider. By reducing build-up of lubrication and storing excess lubrication, the lubrication control recesses avoid failure that may occur as a result of the lubrication interfering with the ABS or the read/write elements of the head.09-09-2010
20100226036DISK DRIVE HAVING MAGNETIC DISK OF PATTERNED MEDIA TYPE - According to one embodiment, a magnetic disk of a patterned media type, has a plurality of zones divided in radial direction on a magnetic recording surface. A plurality of segments which are included in each of the zones includes a data recording area composed of data recording unit of magnetic material and a first resync area in which a reference signal pattern for setting the timing of writing data in the data recording area has been recorded. The number of segments included in each of the zones is an integer and has a common divisor.09-09-2010
20090080104INFORMATION STORAGE APPARATUS FOR DETERMINING STABILITY - According to an aspect of an embodiment, a storage apparatus has a head for writing data into or reading data from a medium, an actuator for moving the head and a controller for applying a driving current to the actuator so as to move the head to a target position over the medium, for superimposing a disturbance current onto the driving current, the controller including a feedback loop which adjusts the driving current so as to move the head toward the target position on the basis of the position data read out from the medium by the head, the controller being configured to determine a frequency characteristic of gain and phase of the feedback loop on the basis of the driving current and the disturbance current.03-26-2009
20100123971RECORDING ELEMENT SUBSTRATE AND RECORDING HEAD INCLUDING RECORDING ELEMENT SUBSTRATE - A recording element substrate includes a recording element array including a plurality of recording elements, a drive circuit configured to drive the recording elements, and a heater located to surround the recording element array as viewed in a direction perpendicular to a surface of the recording element substrate and located above or below a capacitive element or a resistive element included in the drive circuit as viewed on a cross section of the recording element substrate.05-20-2010
20100123970DISK DRIVE, METHOD FOR MEASURING CLEARANCE AND METHOD FOR WRITING SERVO PATTERNS - A disk drive. The disk drive includes a plurality of head-sliders, an actuator, a plurality of clearance adjustment sections, and a controller. Each head-slider includes a slider and a magnetic-recording head on the slider for accessing a disk for storing data. The plurality of head-sliders is secured to the actuator that is configured to move the plurality of head-sliders concurrently. Each clearance adjustment section corresponds to each head-slider of the plurality of head-sliders and adjusts a clearance of the corresponding head-slider. In addition, the controller is configured to position the actuator by servo control with a first head-slider selected from the plurality of head-sliders, to change a clearance of a second head-slider different from the first head-slider by controlling a clearance adjustment section of the second head-slider to bring the second head-slider into contact with a disk, and to detect the contact to measure the clearance of the second head-slider.05-20-2010
20080266702SYSTEM FOR MEASURING HEAD SPACING (FLY HEIGHT) IN A DISK DRIVE - A system and method to measure capacitance between a recording media, such as but not limited to a magnetic disk in a hard disk drive, and a read-write (RW) head is provided. Once the capacitance has been measured, the head spacing may be determined between the RW head and the recording media. This capacitance between the RW head and the recording media, is a function of geometry and the dielectric constant associated with the head spacing. Because the dielectric constant and the area of the RW head and disk are substantially constant, the only change is the separation, i.e. head spacing. Thus, the capacitance becomes a function of the head spacing or fly height.10-30-2008
20080266701MAGNETIC RECORDING DISK WITH IDENTICAL SERVO PATTERNS FORMED ON EACH DISK SURFACE BY SINGLE MASTER TEMPLATE AND DISK DRIVE USING THE DISK - A magnetic recording disk in a disk drive has identical pre-patterned servo patterns on its front and back surfaces. The servo patterns on each disk surface are pre-patterned with a single master template, resulting in the identical pattern on each disk surface. The servo sectors on the two disk surfaces can form identical patterns of angularly spaced arcuate-shaped lines or straight lines that extend radially across the data tracks. However, because the lines on at least one of the disk surfaces do not replicate the path of the recording head, the sampling rate of the servo sectors on that surface is not constant but varies with radial position of the head. To accommodate this, the disk drive's servo control system calculates a timing adjustment from an estimate of the radial position of the head and uses this timing adjustment to adjust the time to open a time window to allow detection of the servo sectors.10-30-2008
20090310247HEAD CONTROL APPARATUS, HEAD CONTROL METHOD, AND MAGNETIC DISK APPARATUS - There is provided a head control apparatus that controls the flying height of a head with respect to a disk by controlling heater current supplied to a heater for head protrusion adjustment. The head control apparatus includes: an acquisition section that acquires flying height information which is information concerning a variation in the flying height of the head; a determination section that determines whether the flying height variation is caused by a variation in atmospheric pressure based on a measured temperature and the flying height information acquired by the acquisition section; and a control section that controls, in the case where the determination section has determined that the flying height variation is caused by a variation in atmospheric pressure, heater current based on control information corresponding to the flying height variation caused by the atmospheric pressure variation.12-17-2009
20090310245METHOD OF CONTROLLING THE POSITION OF A READ/WRITE HEAD AND APPARATUS FOR TESTING A READ/WRITE HEAD - A method of controlling the position of a read/write head relative to a disk in a test apparatus is disclosed. The test apparatus has a positioner for positioning the head. The positioner has a sensor to measure the actual position achieved by the positioner. The method includes generating a sensor signal measuring the actual position achieved by the positioner; generating a position error signal of the head relative to the disk detected at the head; high pass filtering the head position error signal and low pass filtering the sensor signal so that there is substantially no overlap in frequency between them; and, deriving a low frequency head error signal from the head position error signal corresponding to any drift of the head.12-17-2009
20090310244THIN-FILM MAGNETIC HEAD FOR MICROWAVE ASSIST AND MICROWAVE-ASSISTED MAGNETIC RECORDING METHOD - Provided is a thin-film magnetic head that can stably generate electromagnetic field with a desired frequency, even under the existence of significantly strong write field with frequently reversed direction. The head comprises an electromagnetic-field generating element between the first and second magnetic poles. The electromagnetic-field generating element comprises a spin-wave excitation layer provided adjacent to the first magnetic pole and having a magnetization with its direction varied according to external magnetic fields, for generating an high frequency electromagnetic field by an excitation of spin wave. And a magnetization of the spin-wave excitation layer is biased in a direction substantially perpendicular to its layer surface by a portion of magnetic field generated from the first magnetic pole, and pin-wave excitation current flows in the electromagnetic-field generating element in a direction from the second pole to the first pole.12-17-2009
20100123969INFORMATION STORAGE DEVICE AND CONTROL CIRCUIT - According to one embodiment, an information storage device includes: a head reading user data and a start tag indicating a recording start position of the user data in each sector recorded on a medium, the user data and the start tag being read in order of the start tag and the user data; and a controller controlling the head to read a start tag recorded in a preceding sector arranged at a position to be read before a target sector with a movement of the medium, acquiring information on a recording start position of a user data recorded in the target sector based on the start tag read by the head and a relative positional relation between the preceding sector and the target sector, and controlling the head to read the user data recorded in the target sector.05-20-2010
20100123968METHOD OF POSITIONING ELECTROMAGNETIC CONVERSION ELEMENT - According to one embodiment, an electromagnetic conversion element positioning method includes: counting a servo clock for every servo sector radially extending on a recording medium, the servo clock being changed in synchronization with a change in rotation angle of the recording medium; reading magnetic information from spiral servo patterns with an electromagnetic conversion element, the spiral servo patterns being arranged at equal intervals in a circumferential direction of the recording medium, the spiral servo patterns having magnetic materials arrayed along a spiral line maintaining a defined inclined angle with respect to a circumferential line over a predetermined radial region; specifying a position of the spiral servo patterns on the circumferential line based on the read magnetic information; correlating the count value of the servo clock with the specified position; and specifying a radial position of the electromagnetic conversion element based on the correlated count value.05-20-2010
20090135515DISK APPARATUS AND INFORMATION RECORDING DISK - One aspect of the embodiments utilizes a disk apparatus employing a ramp loading method, which includes a ramp member having an overlapping portion with which a part of a disk having an information recording surface and a lateral side overlaps, and a groove is formed on the entire lateral side of the disk. The disk apparatus includes a protrusion formed on a portion of the overlapping portion of the ramp member that is opposed to the lateral side of the disk and the protrusion protrudes into the groove.05-28-2009
20100128380SES ASSISTED WRITE FLY HEIGHT MONITOR AND CONTROL - A hard disk drive that includes a disk, and a head that is separated from the disk by a flying height. The disk drive also includes a circuit that determines the flying height from a signal read during a write operation of the drive. The circuit performs a calibration routine to determine a temperature dependent variable of the signal to offset any temperature effects on the signal used to determine the flying height. The calibration routine can be performed using a spacing error signal (“SES”) generated by the drive.05-27-2010
20100128382MAGNETIC RECORDING DEVICE AND MAGNETIC RECORDING METHOD THEREOF - A magnetic recording device according to one embodiment includes a magnetic recording medium having a magnetic recording layer; a recording element positioned on a head slider; an assistance element for supplying assistance energy to an area on the recording layer to which a recording magnetic field generated by the recording element is applied, the assistance element being positioned on the head slider; and a controller for controlling a size of an assistance area from the assistance element in accordance with a position of the head slider in a radial direction of the magnetic recording medium. Additional systems and methods are also presented.05-27-2010
20100128384MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING APPARATUS - According to one embodiment, a magnetic recording medium to which a signal is recorded by reversing magnetization of a magnetic body, includes: a servo region to which a servo signal is written; a data region configured to include a magnetic region of a track to which data is written, the magnetic region being separated from other magnetic region of other track; and a periodic magnetic pattern region configured to be provided at a head portion of the data region following the servo region, and is inclined at a predetermined angle with respect to a circumferential direction of the magnetic recording medium, over a predetermined length in a radius direction of the magnetic recording medium.05-27-2010
20100079901PRODUCTION METHOD FOR MAGNETIC RECORDING MEDIA AND MAGNETIC RECORDING AND REPRODUCING APPARATUS - A production method for a magnetic recording medium on which a stable lubricant layer can be formed even if unevenness remains on the surface, and the thickness of the lubricant layer is not reduced over time is provided. The method includes forming a lubricant layer (04-01-2010
20100079898MAGNETIC STORAGE APPARATUS AND SERVO INFORMATION REPRODUCING METHOD - A magnetic storage apparatus includes a recording medium having a first area in which servo information for controlling a magnetic head is stored, and a second area in which correction information for correcting the servo information is stored, an amplifying part configured to amplify a reproduced signal obtained by reproducing information recorded in the storage medium by the magnetic head, and a control part configured to define a gain of the amplifying part on the basis of an amplitude of a first reference signal obtained by reproducing a first waveform for amplitude measurement stored in the first area and cause the amplifying part to amplify a first reproduced signal obtained by reproducing the servo information and being configured to define the gain of the amplifying part on the basis of an amplitude of a second reference signal obtained by reproducing a second waveform for amplitude measurement stored in the second area and cause the amplifying part to amplify a second reproduced signal obtained by reproducing the correction information.04-01-2010
20100079902CONTROLLER AND STORAGE DEVICE - According to one embodiment, in a controller of a servo system that performs positioning control of a head by feedback control includes a generating module and a notch filter. The generating module compares a target position and position information decoded from data read by the head from a recording medium to generate a position error signal. The notch filter performs notch filter processing to remove machine vibration of a head driving module on the position error signal. The transfer function H(s) of the notch filter is set to H(s)=[{s04-01-2010
20090180213MAGNETIC RECORDING MEDIUM, METHOD FOR PRODUCTION THEREOF, AND MAGNETIC RECORDING AND REPRODUCING DRIVE - A discrete track-type magnetic recording medium (07-16-2009
20120287529Close loop method for measuring head SNR and media SNR - A close loop method for measuring head SNR, for a storage device comprising a storage media and a head, comprising steps of: (a) loading the head on the media with a dynamic fly height; (b) measuring an initial environmental temperature value Ti and measuring the head signal signal11-15-2012
20120287530THIN-FEMTO MAGNETIC HEAD SLIDER AND METHOD FOR PRODUCING THE SAME - In one embodiment, a magnetic head slider includes a substrate, at least two elements (read element, write element, and/or heater element) positioned adjacent to the substrate, a resistance detection element positioned near the two elements, a pair of conductive terminals in an accessible position and coupled to each of the two elements, a protective film surrounding the two elements and the resistance detection element, a first and a second thin conductive wire extending from the resistance detection clement and terminating at an edge of the protective film, a third thin conductive wire extending from one of the pair of conductive terminals for a first of the two elements and terminating at an edge of the protective film, and a fourth thin conductive wire extending from one of the pair of conductive terminals for a second of the two elements and terminating at an edge of the protective film.11-15-2012
20090279200STORAGE DEVICE, CONTROL CIRCUIT FOR STORAGE DEVICE, AND SERVO-WRITE-MODE IDENTIFYING METHOD - A servo-mark search control unit detects in a magnetic disk a servo mark matching a servo mark selected by a servo-mark candidate selecting unit. In this case, according to an instruction from a servo-mark search control unit, a non-volatile memory managing unit writes servo-write-mode identification information corresponding to the detected servo mark in a servo-write-mode identification-information storage unit of a non-volatile memory. In this manner, a magnetic disk device can recognize by itself a servo write mode with which servo patterns were written in a magnetic disk included in the magnetic disk device.11-12-2009
20090284862HEAD POSITION CONTROL METHOD, HEAD POSITION CONTROL DEVICE, AND MAGNETIC RECORDING EVALUATION APPARATUS - A magnetic head position control method is provided to control a magnetic head to follow the track on a DTM disk by accurately detecting the eccentricity compensation amount through a simple process. An angle detection unit detects θ11-19-2009
20090284863MAGNETIC RECORDING CIRCUIT, MAGNETIC RECORDING DEVICE, AND INFORMATION RECORDING METHOD - A magnetic recording circuit includes a write amplifier that supplies a recording current to a magnetic recording head, and switches a direction of the recording current in accordance with information. The magnetic recording circuit further includes a control circuit that adjusts a rising speed of the recording current.11-19-2009
20090147395TAPE HEAD LAYOUT - A tape head assembly for writing data to and reading data from a tape includes a tape head member having an engagement surface that is configured to engage the tape as the tape moves past the tape head member. A plurality of arrays of interactive elements are supported on the engagement surface. Each array is longitudinally offset from each other array. Each individual array includes a read group having only read elements and a write group having only write elements. Each read group is laterally offset from each write group within each array.06-11-2009
20090290251HARD-DISK DRIVE, METHOD OF CONTROLLING THE HARD-DISK DRIVE, AND METHOD OF MANUFACTURING THE HARD-DISK DRIVE - A hard-disk drive. The hard-disk drive includes a magnetic-recording disk having a plurality of tracks formed thereon. The hard-disk drive also includes a magnetic-recording head configured to be positioned over a target track selected from the plurality of tracks and configured to write data to and to read data from the target track. Moreover, the hard-disk drive includes a range-definer configured to define an allowed range of a position error of the magnetic-recording head corresponding to the target track. In addition, the hard-disk drive includes a write-enabler configured to determine whether writing data by the magnetic-recording head is allowed based on the position error of the magnetic-recording head with respect to the target track and the allowed range that is calculated from data read out by the magnetic-recording head.11-26-2009
20090262451INCREASED FORMAT EFFICIENCY USING DISK SYNCHRONIZED WRITE - A hard disk drive with a disk that has a plurality of data fields. Each data field includes a sync field and a plurality of sync marks. Data is written onto the disk in accordance with a write clock. The write clock is generated and synchronized by the sync field and the sync marks. The sync marks are dispersed throughout the data field so that the write clock is resynchronized as data is written onto the field.10-22-2009
20090262450DATA READING MODULE AND METHOD FOR READING OPTICAL DISC - Disclosed is a data reading module for reading an optical disc with data regions and undesired regions, wherein at least one of the undesired regions is located between the data regions. The data reading module includes: a decoder arranged to decode the optical disc to generate decoded data; a data transferring device arranged to transfer the decoded data; and a controller arranged to control the decoder according to a recorded map indicating the locations of the data regions and the undesired regions; wherein the controller controls the decoder to skip the undesired regions and does not decode the undesired regions while decoding the optical disc.10-22-2009
20080239551STORAGE DEVICE AND STORAGE DEVICE CONTROLLER - A storage device has a head that floats over a rotating storage medium. The storage device includes a measuring unit that measures the operating time and a head slider having a head element. The head element includes a reading element, a writing element and a heater, and a control unit that controls a protruding amount of the head element, by issuing an instruction causing an amount of power of a first predetermined value to be supplied to the heater until the amount of time measured by the measuring unit becomes a predetermined value. When the amount of time exceeds the predetermined value, the control unit cause an amount of power of a second predetermined value that is lower than the first predetermined value.10-02-2008
20090284861DISSIPATION OF LIQUID DROPLETS IN A MAGNETIC DISK DRIVE - Magnetic disk drives and associated methods are described for an improved process for dissipating liquid droplets that may accumulate on a slider of the magnetic disk drive. For the droplet removal process, the slider having the liquid droplet is unloaded from the magnetic disk. For example, the slider may be unloaded from the magnetic disk and onto a ramp assembly. While unloaded from the magnetic disk, a heating power is applied to a TFC heating element in the slider to increase the temperature of the slider. The temperature is increased to a threshold temperature which dissipates any liquid droplets that may have accumulated on the slider. After the liquid droplets have dissipated, the slider may again be loaded onto the magnetic disk.11-19-2009
20100277829METHOD FOR PRODUCING MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING/REPRODUCING APPARATUS - A method for producing a magnetic recording medium having a magnetically partitioned magnetic recording pattern on at least one surface of a nonmagnetic substrate, characterized by comprising a step of reacting portions of a magnetic layer, formed on the non-magnetic substrate, with ozone to modify magnetic properties of said portions of the magnetic layer for forming the magnetically partitioned magnetic recording pattern. The magnetic layer can be a two-layer structure comprising a magnetic layer having a granular structure and formed thereon a magnetic layer having a non-granular structure. The produced magnetic recording medium exhibits a greatly enhanced recording density while recording/reproducing characteristics equal to or better than those of the heretofore proposed magnetic recording mediums are maintained, and it can be produced with an enhanced efficiency.11-04-2010
20090296265HARD-DISK DRIVE - A hard-disk drive (HDD). The HDD includes a main control circuit. The main control circuit includes a frequency-hunting peak filter. The frequency-hunting peak filter includes a peak filter wherein a gain at a center frequency becomes finite and a reciprocal of the transfer function is represented by z/F12-03-2009
20090296264INTEGRATED RECORDING HEAD WITH BIDIRECTIONAL ACTUATION - A recording head for use in magnetic storage devices is disclosed. The recording head includes a transducer that is bi-directionally movable with respect to a surface of the magnetic storage medium, thereby enabling improved positioning of the transducer during recording head read and write operations. Various structures are disclosed to bi-directionally actuate the recording head transducer. In one embodiment, an interleaver assembly having a plurality of flexure assemblies employs a motor including magnetic portions for selective, bi-directional actuation. In another embodiment, electrostatic charges are employed in the flexure assemblies for selective actuation. In yet another embodiment, piezoelectric elements are included to provide for selective actuation.12-03-2009
20090296262FLYING HEIGHT CONTROL METHOD AND CIRCUIT - A method of the present invention is used to control a flying height of a head operable to read data from and write data to a disk of a recording medium housed in an enclosure. In this method, the head is positioned to a predetermined radial measurement location on the disk to obtain error information on errors in the positioning of the head. A frequency analysis is performed on the obtained error information. Disturbance information on errors caused by a wind disturbance is calculated from the frequency analysis result. Pressure information on an air pressure in the enclosure is calculated based on the calculated disturbance information. A control value for controlling a flying height of the head with respect to the disk is determined based on the calculated pressure information. The flying height of the head is controlled based on the determined control value.12-03-2009
20080212227STORAGE MEDIUM DEVICE, DEFORMATION CONTROLLER AND HEAD SLIDER - A storage medium device has at least one head which includes a read head element and a write head element. The device has a deferrable element which changes a distance between the read head element and the write head element in a circumferential direction, a storage unit which stores a control value to be applied to the deferrable element in association with each target track for writing, and a deformation controller which acquires the control value corresponding to the target track for the writing from the storage unit, and applies the acquired control value to the deformable element.09-04-2008
20080212226Disk drive device, altitude determination method therefore and method for determining characteristic of head element portion - Embodiments of the present invention allow for a precise altitude to be calculated from read-out signals of a head slider. In one embodiment, a hard disk controller/multiprocessing unit (HDC/MPU) determines a head element portion in which the instability has occurred in accordance with the resolution change. The HDC/MPU adjusts the clearance accordingly. The head element portion reads signals of different frequencies under a condition of the signal strengths coinciding with a reference value, and the HDC/MPU calculates the resolution. The HDC/MPU determines that the instability has occurred if the difference is outside the criterion. The HDC/MPU uses the read-out signal of a head slider in which the instability has not occurred to calculate the altitude.09-04-2008
20100110581PERPENDICULAR MAGNETIC RECORDING DISK DRIVE WITH PATTERNED DISK HAVING CAPPING LAYER FOR SUPPRESSION OF SURFACE DIFFUSION OF TRENCH MATERIAL - A magnetic recording disk drive has a patterned perpendicular magnetic recording disk of the type that has spaced-apart pillars with magnetic material on their ends and with trenches between the pillars that are nonmagnetic regions. A nonmagnetic capping layer is located in the trenches above the nonmagnetic regions. The substrate has diffusion material in the trenches that when heated will diffuse into the magnetic recording layer material and chemically react with it. The pillars are formed of material that will not diffuse into the recording layer. The recording layer is formed over the entire substrate and a nonmagnetic capping layer that is not chemically reactive with the diffusion material is formed over the recording layer in the trenches. The substrate is annealed to cause the recording layer material in the trenches and the material in the substrate to diffuse into one another and chemically react to render the trenches nonmagnetic. The capping layer suppresses the diffusion of material from the substrate to the surface in the trenches and thus prevents migration of diffusion material to the recording layer material on the ends of the pillars.05-06-2010
20120293889METHOD AND APPARATUS FOR OPERATING A STORAGE DEVICE - Method for operating a storage device with a tape and a head wherein the head comprises a first and a second read element. Each read element is operable to detect servo-pattern of a particular servo band. The first and the second read element are arranged such that the tape at first passes one of both read elements and subsequently passes the other of both read elements when the tape moves in a predetermined longitudinal direction. A tape transport direction of the tape along the longitudinal direction is determined. The first read element is selected dependent on the determined tape transport direction, when the determined tape transport direction represents a direction where the tape at first passes the first read element and subsequently the second read element. Otherwise the second read element is selected. A position error signal is determined dependent on the selected read element.11-22-2012
20120293888SYSTEMS AND METHODS FOR REDUCING A USER'S ABILITY TO PERCEIVE HARD DRIVE NOISE - A system for reducing a user's ability to perceive noise generated by a storage device. The system includes a processing unit and a storage device communicably coupled to the processing unit. The storage device may be, for example, a hard disk drive. The processing unit is provided with computer implemented instructions to: (i) receive a content stream comprising an audio component and a video component, wherein the content stream further comprises volume data and timing data relating to the audio component; and (ii) instruct the storage device to carry out read/write operations of the hard disk drive based, at least in part, on the volume data and the timing data.11-22-2012
20080239548Multiple sector reassign on write error for disk drive - A disk drive includes a disk for storing information representing data, and a memory device. A method for writing includes locating a first data sector on a disk where a write operation fails, identifying the first data sector and a plurality of other data sectors near the first data sector as a grown defect, and storing the location of the first data sector and the plurality of other data sectors on a grown defect list. The memory device includes a list of grown defects that identifies a plurality of data sectors stored along a track between the first servo wedge and the second servo wedge on a selected track as data sectors which may not be written to.10-02-2008
20080239550Head slider, magnetic storage device and control circuit, having cleaning mechanism - The present invention relates to a head slider used for a magnetic storage device. In accordance with an aspect of the present invention, a head slider having an air bearing surface comprising, a heater element disposed at the air bearing surface, and at least one groove formed in an end surface at a trailing edge side of the head slider so as to extend toward a rear surface.10-02-2008
20080239547DISK DRIVE APPARATUS, ELECTRONIC CIRCUIT FOR DISK DRIVE APPARATUS AND POWERING METHOD THEREFOR - According to one embodiment, a disk drive apparatus includes a disk having a plurality of tracks formed of approximately concentric patterns, a head slider reading and writing data from and to the disk, a motor driver configured to move the head slider to a target position on the disk, an electronic circuit configured to transfer the data to and from a host computer, and a power source configured to provide power to the electronic circuit based upon a position of the head slider.10-02-2008
20110141609ONSET LAYER FOR PERPENDICULAR MAGNETIC RECORDING MEDIA - A magnetic storage medium according to one embodiment includes a substrate; an onset layer formed above the substrate, the onset layer comprising ruthenium and titanium oxide; and a magnetic oxide layer formed directly on the onset layer. A method according to one embodiment includes sputtering using a target of ruthenium and titanium oxide for forming an onset layer above a substrate, the onset layer comprising ruthenium and titanium oxide; and forming a magnetic oxide layer directly on the onset layer. Additional systems and methods are also presented.06-16-2011
20080278842CORRECTED READ/WRITE OFFSET COMPENSATION - A read trajectory and/or a write trajectory of a read/write head of a rotatable disk drive is adjusted using a compensation signal that compensates for a time-varying difference between the read trajectory and the write trajectory.11-13-2008
20080291566DEVICE SELECT SYSTEM FOR MULTI-DEVICE ELECTRONIC SYSTEM - In one general embodiment, a system includes a first device on a first substrate; a second device on a second substrate; and a device select system coupled to the first and second devices. The device select system includes: a first portion having an array of first electrical contacts; a second portion having an array of second electrical contacts, there being more second electrical contacts than first electrical contacts, the second portion being coupled to the first and second devices, each of the first electrical contacts being associated with at least two of the second electrical contacts; and a select mechanism for selectively placing each of the first electrical contacts in electrical communication with one of the second electrical contacts associated therewith.11-27-2008
20080291564Detecting head-disk contact during off-track operations - A disk drive that can detect contact between a head and a disk during an off-track operation such as a seek routine, a ramp load or a head take-off. The disk drive includes a circuit that causes the head to move across the disk in a seek routine. A head heater element is driven to move the head into contact with the disk. A read signal provided by the head is filtered through a band pass filter that has a center frequency. The frequency that produces the maximum signal is selected as the center frequency for the band pass filter. The drive can monitor subsequent head contact during an off-track operation by detecting output from the band pass filter.11-27-2008
20080291565CONTROL APPARATUS, STORAGE APPARATUS, AND WRITING CONTROL METHOD - A control apparatus detects positional information of a head performing writing processing every predetermined time interval, and computes next-sample projected positional information of the head based on the difference between the positional information detected the previous time and the positional information detected the current time, and the current detected positional information for every position information detected. The control apparatus determines whether the computed next-sample projected positional information is greater than a next-sample projected position threshold which is a predetermined threshold. Following this, in the case that determination is made that the next-sample projected positional information is greater than the projected position threshold, the disk control apparatus controls a storage device to stop the writing processing after the writing processing is performed through the end of the sector wherein the writing processing is currently being performed.11-27-2008
20100182719LUBRICANT AGENT AND MAGNETIC STORAGE DEVICE - According to one embodiment, a lubricant agent comprises a fluorine polymer represented as follows:07-22-2010
20120194943MAGNETIC DISK DRIVE AND METHOD FOR CONTROLLING MICROACTUATOR IN MAGNETIC DISK DRIVE - According to one embodiment, a magnetic disk drive includes a detector and a servo controller. The detector detects, as actual timestamps, time intervals at which a head reads servo sync marks recorded on a disk at predetermined intervals. The servo controller controls a VCM actuator and a microactuator with feedback control in order to position the head at a target position. The servo controller comprises a feedforward controller configured to compensate for disturbance. The feedforward controller comprises a difference detector and an integrator. The difference detector detects a deviation of the actual timestamps from target timestamps as a timestamp difference. The integrator configured to convert the detected timestamp difference into displacement of the microactuator by integrating the detected timestamp difference. The feedforward controller provides a manipulating variable corresponding to the converted displacement, to a feedback control loop for the microactuator as a feedforward manipulating variable.08-02-2012
20100277828Method and system for fluid mediated disk activation and deactivation - Embodiments of methods and systems for controlling access to information stored on memory or data storage devices are disclosed. In various embodiments, fluid-mediated modification of information or access to information is utilized. According to various embodiments, data storage devices designed for rotating access are described which include rotation-activated fluid control mechanisms.11-04-2010
20080310046Class H Drive - A method for driving a load by using an output stage amplifier in full bridge configuration whose supply is modulated by means of a fast switching power converter, controlled in order to maintain the stage's output common mode at its minimum voltage, is presented. The modulation of the switching power converter output is obtained by a feedback control system regulating directly the voltage of the bridge output stage terminals. This bridge unipolar class H stage allows driving the load with high accuracy and improved efficiency without introducing switching noise and EMI at the load terminals typical of PWM driving. This method can be applied with the same benefits to class AB, pseudo class AB or to class A output stages. When this method is associated with an imposed current driving approach and with a current oversampling digital to analog converter the resulting advantages are very significant for accurate motor control applications.12-18-2008
20100265614SERVO PATTERN WRITING METHOD OF HARD DISK DRIVE - A method of writing a servo pattern in a hard disk drive includes manufacturing a master pattern, and writing the reference servo pattern to the disk by using the master pattern and a magnet for magnetizing the disk. The master pattern includes a plurality of ammonite cycles that have substantially the same pattern as the reference servo pattern and are radially formed from the outside toward the inside of the disk. A final servo pattern may be written using the reference servo pattern.10-21-2010
20080239552INFORMATION PROCESSING APPARATUS - According to one embodiment, an information processing apparatus includes a disk-shaped recording medium, a drive section which rotates the recording medium, a head which records and reproduces information to and from the recording medium, a nonvolatile main memory which stores data in the recording medium, a memory mounting section in which a nonvolatile expansion memory is detachably mountable from outside, and a control section which reads data equivalent to a memory capacity of the expansion memory from the recording medium and writes the data to the expansion memory when the expansion memory is mounted in the memory mounting section.10-02-2008
20110007416DISK DRIVE AND METHOD FOR MEASURING CLEARANCE BETWEEN A HEAD AND A DISK IN A DISK DRIVE - A disk drive. The disk drive includes a disk, a head, a head-slider, a moving mechanism, and a controller. The head is configured to access the disk. The head-slider includes the head, and is configured to fly in proximity to a recording surface of the disk. The moving mechanism is configured to move the head-slider over the disk, and to support the head-slider. The controller is configured to read out at least one from a plurality of clearance-measurement data strings from the recording surface of the disk using the head, and to calculate a clearance between the head and the disk from clearance-measurement results obtained from a plurality of resolutions with different frequency components.01-13-2011
20110007417THIN FILM PERPENDICULAR MAGENTIC RECORDING HEAD, THEIR FABRICATION PROCESS AND MAGENTIC DISK DRIVE USING IT - Thin film perpendicular magnetic head with a narrow main pole capable of a high recording density in excess of 100 gigabits per square inch and generating a high magnetic recording field, while also being modified to suppress remanent magnetic fields occurring immediately after writing operation. A return path is provided for supplying a magnetic flux to the main pole, and an conductive coil for excitation of the main pole and return path. The main pole has a pole width of 200 nanometers or less, and a magnetic multilayer made up of a high saturation flux density layer and low saturation flux density layer. The low saturation flux density layer and the high saturation flux density suppress remanent magnetization and prevent erasing after writing by utilizing a closed magnetic domain structure in the pole.01-13-2011
20100142083MAGNETIC RECORDING MEDIUM AND MAGNETIC STORAGE DEVICE - According to one embodiment, a magnetic recording medium includes a substrate and a single domain magnetic dot. The single domain magnetic dot is provided on the substrate and is written with a compensation signal for controlling the position of at least one of a recording device and a reproducing device. The single domain magnetic dot has a length in the radial direction of the substrate shorter than a length in the circumferential direction of the substrate.06-10-2010
20100142082DISK DRIVE AND METHOD FOR HEAD SERVO CONTROL OF THE DISK DRIVE - A disk drive. The disk drive includes a head, a moving mechanism, a first peak filter, an adaptive peak filter, and a filter controller. The head is configured to read servo data on a disk at sampling frequency. The moving mechanism is configured to move the head in proximity with a recording surface of the disk. The first peak filter has a fixed peak frequency and a variable gain, and is configured to be inserted into a servo loop. The servo loop is configured to position the head with position error signals between servo data read by the head and a target position. The adaptive peak filter has a variable peak frequency and a variable gain, and is configured to be inserted into the servo loop. The filter controller is configured to control the gain of the adaptive peak filter according to the gain of the first peak filter.06-10-2010
20090122437Fly height adjustment device calibration - A method for calibrating a fly height adjustment device comprises flying a magnetic transducer coupled with a head gimbal assembly at a fly height from a magnetic recording data track. The magnetic transducer is coupled with a fly height adjustment device. Read-back signal amplitude is read from the magnetic recording data track with the magnetic transducer. The fly height is decreased with the fly height adjustment device. A linear fly height prediction is generated from the read-back signal amplitude and from power delivered to the fly height adjustment device as the fly height is decreased. The power delivered to the fly height adjustment device is compared with a difference between the linear fly height prediction and an implied fly height from the read-back signal amplitude, thereby calibrating the fly height adjustment device.05-14-2009
20100271730METHOD FOR PRODUCING MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING/REPRODUCING APPARATUS - A method for producing a magnetic recording medium having a magnetically partitioned magnetic recording pattern on a surface of a nonmagnetic substrate, which comprises the following steps. Step (A) of forming a magnetic layer on a non-magnetic substrate, step (B) of forming a carbon layer on the magnetic layer, step (C) of forming a resist layer on the carbon layer, step (D) of forming a negative pattern of magnetic recording pattern on the resist layer, step (E) of removing the portions of resist layer and carbon layer in regions corresponding to the negative pattern, step (F) of removing at least a surface layer portion of the magnetic layer in the regions corresponding to the negative pattern, and optional step (G) of removing the residual resist layer and carbon layer. The produced magnetic recording medium has a recording/reproducing property equal to or better than conventional ones and exhibits a high recording density.10-28-2010
20100142080METHODS AND APPARATUS TO DETECT SURFACE CHARACTERISTICS ON MAGNETIC READ/WRITE HEADS - A method and apparatus for detecting predetermined surface characteristics in head gimbal assemblies to improve hard disk drive reliability. The predetermined surface characteristics include head slider protrusions such as scratches or contamination that can cause damage to the head or disk in hard drives. By detecting these protrusions, those drives with an increased chance of failure can be removed from a test group, thereby increasing the quality and reliability of the remaining disk drives. The invention provides a method of detecting these protrusions that is a more practical option than using a scanning electron microscope (SEM) to inspect each head slider.06-10-2010
20120140356PERPENDICULAR MAGNETIC RECORDING HEAD WITH DOMAIN CONTROLLED SIDE SHIELD - In one embodiment, a perpendicular magnetic head includes a main magnetic pole, a trailing shield, and a multilayered side/leading shield disposed on a leading side of the main magnetic pole in a down-track direction and on either side of the main magnetic pole in a cross-track direction. The side/leading shield includes an inner layer nearer to the main magnetic pole which surrounds the main magnetic pole on three sides and an outer layer farther from the main magnetic pole than the inner layer which surrounds the main magnetic pole and inner layer on three sides. The inner layer has a saturation magnetization (Ms) that is greater than a Ms of the outer layer, and the trailing shield has a relative permeability of greater than about 50. Other magnetic heads and methods of producing magnetic heads are also presented according to various embodiments.06-07-2012
20090128947DISK DRIVE DETERMINING OPERATING FLY HEIGHT BY DETECTING HEAD DISK CONTACT FROM DISK ROTATION TIME - A disk drive is disclosed including a disk having a plurality of tracks, wherein each track comprises a plurality of data sectors and a plurality of servo sectors. The disk drive further comprises a spindle motor for rotating the disk, and a head actuated radially over the disk, wherein the head comprises a dynamic fly height (DFH) heater. Control circuitry within the disk drive is operable to select an operating control setting for the DFH heater by positioning the head over one of the tracks, measuring a first rotation time of the disk in response to at least one of the servo sectors, adjusting the control setting for the DFH heater, measuring a second rotation time of the disk in response to at least one of the servo sectors, and detecting whether the head has contacted the disk in response to the first and second rotation times.05-21-2009
20110205663METHOD OF PRODUCING MAGNETIC STORAGE MEDIUM, MAGNETIC STORAGE MEDIUM AND INFORMATION STORAGE DEVICE - It is an object to produce a magnetic storage medium of a high recording density by a production method that does not impair mass productivity, and a magnetic storage medium 08-25-2011
20090128948METHODS AND APPARATUS TO CONTROL HEAT DISSIPATION IN HARD-DISK DRIVES - Methods and apparatus to control heat dissipation in hard-disk drives (HDDs) are disclosed. A disclosed example apparatus comprises a semiconductor die, a ground bump positioned on the die, and a hard-disk drive writer head positioned on the die relative to the ground bump based on a thermal impedance.05-21-2009
20090185306GAP SERVO CONTROL METHOD AND APPARATUS IN NEAR-FIELD OPTICAL DISC DRIVE - A gap servo control method and apparatus for increasing a disturbance cancellation capability and decreasing the occurrence of an overshoot in a near-field optical disc drive include: generating an actuator driving signal of a transient response process by using a signal obtained by removing a disturbance contained in the gap error signal using a first band when a level of a gap error signal reaches a first level; and generating the actuator driving signal of the transient response process by using a signal obtained by removing the disturbance contained in the gap error signal using a second band when the level of the gap error signal reaches a second level.07-23-2009
20090141390MAGNETIC DISK APPARATUS AND MAGNETIC DISK APPARATUS CONTROL METHOD - A magnetic disk apparatus has a heater for heating a head incorporated in the magnetic disk apparatus, an atmospheric pressure detector for detecting a change in atmospheric pressure in the magnetic disk apparatus, and an adjuster for adjusting a thermal dose supplied to the head by the heater according to the change in atmospheric pressure detected by the atmospheric pressure detector.06-04-2009
20090141391Disk drive device and clearance control method thereof - Embodiments of the present invention help to precisely control the clearance between a head and disk for the pressure without using a barometric sensor. In an embodiment of the present invention, an HDD determines a clearance from variations in operational parameters, and further determines a variation in pressure by deducting the clearance variation caused by a variation in temperature from the clearance. When the HDD controls the clearance in accordance with the pressure change, the HDD checks for head-disk contact. The accuracy and reliability in pressure measurement (clearance measurement) using operational parameters are not high. Therefore, confirming the pressure measurement by the presence or absence of head-disk contact eliminates head-disk contact in the following read/write operation to attain a securer margin for the clearance.06-04-2009
20080316637NON-CONTACT MEASUREMENT OF SLIDER FLY HEIGHT BY ELECTROSTATIC FORCE - In a system and method for a non-contact measurement of the fly height of a slider above a magnetic data storage medium using electrostatic force, a slider with a read/write head flies over a magnetic data storage medium. A series of distinct voltages are applied between the slider and the magnetic data storage medium, and corresponding read-back signals are recorded. Using the recorded read-back signals, coefficients for an empirical curve-fit equation are calculated. The coefficients are normalized and converted into a fly height measurement.12-25-2008
20080316635Deriving servo PES from DC erased bursts in perpendicular recording - A hard disk drive with a disk that has DC erased servo bursts. The DC erased servo bursts are read by a perpendicular recording head that produces a relatively square burst signal. The burst signal is used determine a position error signal and center the head on a track of the disk.12-25-2008
20090052080Monitoring a fly height of a magnetic transducer - A method for monitoring a fly height of a magnetic transducer comprises flying the magnetic transducer at a distance of separation from a recording media. The fly height is modulated with a predetermined modulation frequency with a fly height control device. A read-back signal is read from the recording media with the magnetic transducer. A change of the read back signal is measured that results from modulating the fly height. A fault signal is provided in response to the change crossing a threshold.02-26-2009
20110141614Magnetic Head Drive Device - A magnetic head drive device including a suspension for supporting a magnetic head, and a main actuator that produces rotary movement of the magnetic head by applying current to a coil. The main actuator includes end arms each comprising a single micro-actuator, and an intermediate arm comprising two micro-actuators. The micro-actuators of the end arms are driven in the same direction, and the micro-actuators of the intermediate arm are driven in the opposite direction to the drive direction of the micro-actuators of said the arms.06-16-2011
20090080107METHOD OF CONTROLLING MOVEMENTS OF A POSITION OF A MICROSCANNER - The invention relates to a method of controlling movements of a positioner of a micro-scanner, the method comprising: determining the vibration resonance frequency ranges of the positioner, and performing a main scan by a controlled movement of the positioner.03-26-2009
20090080105Magnetic recording head and magnetic recording device - It is made possible to provide a magnetic head that can stabilize the high-frequency magnetic field generated from the spin torque oscillator. A magnetic head includes: first and second main magnetic poles; and a spin torque oscillator provided between the first and second main magnetic poles.03-26-2009
20110141611METHOD AND APPARATUS FOR MEASURING DISK RUNOUT IN A DISK DRIVE - According to one embodiment, a disk drive includes an actuator, a servo controller, and a calculation module. The actuator is configured to move the head over a disk, in the radial direction of the disk. The servo controller is configured to make the head move along a target orbit on the disk, in accordance with the distance the actuator has been moved. The calculation module is configured to calculate, as disk runout, a virtual target orbit value supplied to the servo controller to suppress the disturbance at the target orbit.06-16-2011
20110141608MAGNETIC DISK CENTERING METHOD AND SYSTEM - A system and method are described for aligning a data axis of one or more circular data-bearing tracks on an annular surface region of a magnetic media-bearing disk, with a spin axis of a spindle of a spinstand or a disk drive. The data axis is perpendicular to the surface region of the disk and the data tracks are concentric with respect to a data axis.06-16-2011
20110141607Write Quality of HDD Heads Experiencing Temporary Fly-Height Problems - Approaches for improving the write quality of a hard-disk drive (HDD) head experiencing temporary fly-height problem. When the hard-disk drive is idle and heads are parked on the ramp, fluid, such as a lubricant or the condensation of vapor, may collect between the surface of a platter and the head or a slider, thereby causing the head to temporarily fly higher than normal. An HDD may include electronic component(s) configured to (a) determine whether it is likely that fluid is interposed between the surface of a magnetic-recording disk and the slider or the head, and (b) temporarily adjust one or more of (i) a thermal fly height control setting of the head and (ii) a write parameter of the head to compensate for the head flying higher than normal as a result of the fluid being interposed between the surface of the disk and the slider or the head.06-16-2011
20110141615MAGNETIC HEAD FOR PERPENDICULAR RECORDING - According to one embodiment, a magnetic head for perpendicular recording includes a main pole, a first soft magnetic film disposed on a trailing side of the main pole, and a first nonmagnetic film interposed between the main pole and the first soft magnetic film. A thickness of the main pole is increased in a depth direction from an air bearing surface using an inclination, and a thickness of the first nonmagnetic film increases in the depth direction from the air bearing surface. In another embodiment, an angle from a horizontal plane of an upper surface of the first nonmagnetic film is greater than an angle from a horizontal plane of a lower surface of the first nonmagnetic film in contact with the main pole. Other heads, methods, and systems are described according to more embodiments.06-16-2011
20090086361STORAGE APPARATUS AND METHOD FOR PROCESSING RECORDING COMPENSATION - According to an aspect of an embodiment, a storage apparatus has a storage for storing a plurality of compensation values in association with a plurality of bit sequence patterns, a head for writing data into a medium and a controller for controlling the apparatus and driving the head, the controller determining whether to use one of the compensation values to drive the head to write an instantaneous data bit in dependence upon the immediate preceding data bits in reference to the bit sequence patterns.04-02-2009
20110228423MAGNETIC RECORDING HEAD, MAGNETIC HEAD ASSEMBLY, AND MAGNETIC RECORDING/REPRODUCING APPARATUS - A magnetic recording head includes a first ferromagnetic layer, an intermediate layer, a third ferromagnetic layer, a first magnetic pole and a second magnetic pole. The intermediate layer is provided between the first ferromagnetic layer and the second ferromagnetic layer. The third ferromagnetic layer includes a CoIr alloy and is provided so that the first ferromagnetic layer is sandwiched between the third ferromagnetic layer and the intermediate layer. The first magnetic pole is provided so that the third ferromagnetic layer is sandwiched between the first magnetic pole and the first ferromagnetic layer. The second magnetic pole is provided so that the second ferromagnetic layer is sandwiched between the second magnetic pole and the intermediate layer.09-22-2011
20110228422ULTRA FAST DISK ACCESS USING ARRAYS OF FIXED READ/WRITE TRANSDUCERS - An apparatus comprising a magnetic media and a read/write unit. The magnetic media may be configured to store data. The magnetic media may also be rotated during access of the magnetic media. The read/write unit may comprise a plurality of transducers arranged in a linear array. Each of the transducers may be fabricated on a semiconductor substrate with fixed head positions with respect to the magnetic media. The read/write unit may also be positioned in close proximity to and across the surface of the magnetic media. Each transducer may be configured to read data from the magnetic media and write data to the magnetic media.09-22-2011
20110141613TUNNELING MAGNETORESISTANCE READ HEAD HAVING A COFE INTERFACE LAYER AND METHODS FOR PRODUCING THE SAME - According to one embodiment, a method for producing a Tunneling Magnetoresistance (TMR) read head includes forming a fixed layer, forming an insulating barrier layer above the fixed layer, forming a free layer above the insulating barrier layer, and annealing the free layer, the fixed layer, and the insulating barrier layer. The fixed layer includes a first ferromagnetic layer having a Co06-16-2011
20090002870Flying height measurement and control with user data signal - A hard disk drive that determines a flying height from a slope of a line created from a ratio of amplitudes of frequencies in response to impulse functions. A first set of amplitudes of reference frequencies can be determined from a reference impulse. A second set of amplitudes of data frequencies can be determined from a data impulse during operation of the disk drive. Ratios of amplitudes of the data and reference frequencies at different discrete frequencies can be plotted. The slope of the plotted line corresponds to the difference between the flying height when the reference impulse is generated and the flying height when the data impulse is generated. The disk drive may utilize the slope in a feedback routine to control the flying height.01-01-2009
20090103203RECORDING APPARATUS AND CONTROL CIRCUIT - It relates to a hybrid recording apparatus using. The recording apparatus includes a magnetic disk medium for recording and reading data by a magnetic head, a nonvolatile memory in which a write cache area is allocated, a cache control unit for temporarily loading write data, which is recorded on the magnetic disk medium, into the write cache area in accordance with a write request from a higher-level apparatus. A memory allocation management unit stores memory management information in the magnetic disk medium for management thereof, the memory management information representing an allocated position of the write cache area in the nonvolatile memory.04-23-2009
20090213486DATA RECORDING DEVICE - A data recording device for storing data, the data recording device includes: a medium for storing data; a head assembly including a read element for reading out data stored in the medium and a heater for controlling a distance between the read element and the medium within a predetermined range during data reading out by the read element; and a processor for executing a test process comprising: controlling the distance between the read element and the medium in a test range outside the predetermined range by controlling the heater, and reading out test data from the medium while the distance between the read element and the medium is maintained in the test range so as to evaluate the data recording device.08-27-2009
20090257144Perpendicular magnetic recording medium and magnetic storage device using the same - Embodiments of the present invention provide a perpendicular magnetic recording medium that reduces the noise of granular recording layers, obtains sufficient overwrite characteristic that suppresses an increase in the magnetic cluster size, and allows high-density recording. According to one embodiment, a perpendicular magnetic recording medium comprising substrate having thereon at least soft magnetic layer, nonmagnetic intermediate layer, a perpendicular recording layer and protective layer formed in that order. The perpendicular recording layer consists of three or more layers of first recording layer, a second recording layer, and a third recording layer from the side nearer to the substrate. The first recording layer and the second recording layer have a granular structure comprising a grain boundary of an oxide surrounding ferromagnetic crystal grains containing Co and Pt, and the third recording layer has a non-granular structure mainly comprising Co and not containing an oxide. The grain boundary of the first recording layer contains Si, Cr and oxygen, and at least one element selected from Ti, Ta and Nb, and the grain boundary of the second recording layer contains Cr and oxygen, or contains Cr and oxygen and at least one element selected from Si, W and V.10-15-2009
20090219646POSITIONING CONTROL SYSTEM AND METHOD THEREFOR - There is provided with a positioning control system which includes: a head moving unit configured to move a head for recording or reproducing information with respect to a disk capable of recording information; a position detecting unit configured to detect a position of the head; an error detecting unit configured to detect a position error signal of a detected head position with respect to a predetermined target position; a compensation controller configured to generate control input by performing phase lead compensation and phase delay compensation for the position error signal and supply the control input to the head moving unit; and a gain controller configured to control at least one of gains the phase lead compensation and the phase delay compensation based on frequency components contained in the position error signal and an amplitude of the position error signal.09-03-2009
20090244766INFORMATION ACCESS DEVICE - A difference value between a gain control value when a head comes into contact with a recording medium and a gain control value when the head floats with respect to the recording medium by a target floating amount is stored in advance. When the information access device is actually operated, supply power to a heater is adjusted to once bring the head into contact with the recording medium, a first gain control value adjusted by a gain control section when the head comes into contact with the recording medium is obtained, a second gain control value to be adjusted by the gain control section when the head floats from the recording medium by the target floating amount is obtained from the first gain control value and the difference value, and the supply power to the heater is adjusted such that the second gain control value is supplied to a gain variable amplifier by the gain control section.10-01-2009
20120106000HEAD POSITION CONTROL METHOD AND DISK DEVICE - A track locus drawn on a disk discretely contains repeatable runout (RRO) components which are large in amplitude up to high-frequency band. In order to position a magnetic head along the track locus using filters good at suppressing RRO with resonance characteristics only at an integral multiple of a rotation frequency, many filters are required and thus it takes a long time for all the filters to go into a steady state. After learning until the filers go into a steady state, output values of the filters in a steady state are stored on a disk or in a memory. According to controlling the magnet head using these stored output values, the time required for the filters to go into a steady state becomes unnecessary.05-03-2012
20090257143THIN-FILM MAGNETIC HEAD HAVING FUNCTION OF ADJUSTING CLOSURE HEIGHT - Provided is a thin-film magnetic head, in which the magnetic spacing can be controlled appropriately, regardless of the presence of the variation in height of the medium-opposed surface of the closure. The thin-film magnetic head comprises: at least one head element formed on or above an element-formation surface of a substrate, for reading data from a magnetic recording medium and/or writing data to a magnetic recording medium; an overcoat layer formed on the element-formation surface so as to cover the at least one head element; and at least one closure adhered to at least a portion of an upper surface of the overcoat layer. Here, at least one of the at least one closure comprises at least one height-adjusting means for adjusting the height of a medium-opposed surface of the closure. The height-adjusting means is preferably a heating means provided within the closure.10-15-2009
20100177432INFORMATION STORAGE APPARATUS, METHOD FOR CORRECTING FEED PITCH OF READ/WRITE HEAD, AND METHOD FOR FORMING SERVO PATTERN - According to one embodiment, an information storage apparatus comprises a storage medium with a first servo pattern having absolute position information and a second servo pattern having relative position information, a pitch correction module configured to move a head with an initial feed pitch by using the second servo pattern by a target distance determined from the first servo pattern, and to correct the initial feed pitch based on a moving distance of the head and a target distance, a head position controller configured to position the head based on the initial feed pitch corrected by the pitch correction module and information of the first and the second servo patterns, and a recording signal generator configured to generate a control signal for making the head record the third servo pattern having the absolute position information.07-15-2010
20080259487Media drive, processing method for recording data onto a medium, processing method for data read from a medium, and method for controlling a process for reading data from a medium - Embodiments of the invention control a recovery procedure effectively in accordance with write conditions. In one embodiment, the data to be written into a sector includes not only user data but also recording condition data, which indicates the temperature prevalent during a write. If a data read is not accurately performed, a recovery procedure is executed. If a data read is accomplished by a retry and the temperature prevalent during a write is lower than predetermined, it is concluded that the employed medium is nondefective. Thus, the read data is rewritten into the same sector without being stored in a spare area. This prevents the spare area from being unnecessarily consumed.10-23-2008
20110141612METHOD OF UNLOADING TRANSDUCER IN DATA STORAGE DEVICE AND DISK DRIVE AND STORAGE MEDIUM USING THE METHOD - Provided are a method and apparatus for performing optimum transducer unloading in a data storage device according to circumstances. The method of unloading a transducer in a data storage device comprises: determining whether a condition that requires an unloading operation is detected while the transducer is positioned on a data area on a disk; selecting, when the condition that requires the unloading operation is detected, an unloading mode corresponding to the detected condition from among a plurality of unloading modes; and moving the transducer to an area other than the data area on the disk according to the selected unloading mode.06-16-2011
20090316293POSTURE ADJUSTMENT METHOD OF MAGNETIC HEAD - A posture adjustment method of magnetic heads includes a method in which a magnetic head initial position adjustment apparatus 12-24-2009
20090059417APPARATUS FOR ASSISTING WRITE OPERATION USING HIGH FREQUENCY MAGNETIC FIELD IN DISK DRIVE - According to one embodiment, a disk drive having a spin torque oscillator and designed to perform high frequency assisted writing. The disk drive has a magnetic disk, a magnetic head, a coil, and a drive current controller. The drive current controller controls a drive current to supply to the spin torque oscillator. To record data magnetically in the disk, the drive current controller supplies to the spin torque oscillator the drive current that changes in synchronism with the polarity inversion of the recording current supplied to the coil, which excites the recording magnetic pole of the magnetic head.03-05-2009
20090316290SYSTEMS AND METHODS FOR WRITING SERVO PATTERNS - A method for writing a servo track according to one embodiment comprises monitoring a lateral position of a magnetic tape passing over a servo writing head during a servo track writing operation; and writing servo marks to the magnetic tape, a timing of the writing of each mark being based on the monitored position of the magnetic tape. A system for writing a servo track according to one embodiment comprises a servo writing head for writing servo marks onto a magnetic tape; a device for optically monitoring a position of the magnetic tape during a servo track writing operation; and a controller for controlling a timing of the writing of the servo marks to the magnetic tape based on the monitored position of the magnetic tape. Additional systems and methods are also presented.12-24-2009
20090316294HEAD POSITIONING CONTROL METHOD, MAGNETIC DISK APPARATUS AND FEEDBACK CONTROL METHOD - According to one embodiment, a head positioning control method comprises suppressing a first frequency component and increasing a second frequency component of a control signal for moving a head to a desired position over a magnetic disk, and moving the head to the desired position over the magnetic disk by an actuator based on the control signal.12-24-2009
20090316291TANDEM MAGNETIC WRITER - A magnetic head in one embodiment comprises a pole; a first write gap in the pole; a first coil for generating a magnetic flux across the first write gap; a second write gap in the pole having at least a portion thereof aligned with the first write gap in a direction parallel to a direction of media travel thereover; and a second coil for generating a magnetic flux across the second write gap, the second coil being addressable independently of the first coil. A method in one embodiment comprises forming a first write coil; forming a first write gap; forming a second write gap having at least a portion thereof aligned with the first write gap in a direction parallel to a direction of media travel thereover; forming a second coil for generating a magnetic flux across the second write gap, the second coil being addressable independently of the first coil; and forming one or more write poles, wherein a write pole region adjacent the first and second write gaps is formed concurrently.12-24-2009
20100014186POSITION CONTROL APPARATUS AND DISK APPARATUS USING THE SAME - According to one embodiment, a position control apparatus includes: a digital control module that performs position control including disturbance adaptive control with a predetermined sampling period with the use of a control constant, in accordance with a position error between a target position and a current position of the object; and a table that stores the control constant corresponding to a value of sin(ωT/2), wherein the digital control module determines a control value of the actuator in accordance with the position error, calculates the value of sin(ωT/2) according to an adaptive law from a signal based on the position error, reads the corresponding control constant from the table in accordance with the calculated value of sin(ωT/2), and updates the control constant.01-21-2010
20090296260Device and method for specifying control value for controlling clearance between head and disk, and magnetic disk drive device - Embodiments of the present invention help to detect contact between a head and a magnetic disk more accurately in specifying a heater power value for adjusting a clearance between a head element portion and the disk. According to one embodiment, a hard disk controller/multiprocessing unit (HDC/MPU) measures amplitudes of read signals in a user data field DATA. A hard disk drive (HDD) fills a gap between servo data with single data sector. The HDC/MPU measures the amplitudes of read signals in each data sector at different heater power values. It determines the heater power value at which contact occurs from the measured values.12-03-2009
20100157465CURRENT PERPENDICULAR TO PLANE (CPP) MAGNETIC READ HEAD - One general embodiment of the present invention is a magnetic read head including a magnetoresistive sensor where sense current flows in a stacking direction of the magnetoresistive sensor, i.e., perpendicular to the plane of the layers of the head. The magnetoresistive sensor comprises a free layer having a magnetization direction that is affected by external magnetic fields and includes a Heusler alloy layer and a Co-based amorphous metal layer, a fixed layer which is stacked with the free layer and has a fixed magnetization direction, and a non-magnetic intermediate layer between the free layer and the fixed layer.06-24-2010
20100182717METHOD FOR MANUFACTURING MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING-REPRODUCING APPARATUS - Provided is a method for manufacturing, in a simple process, a magnetic recording medium having a distinct magnetic recording pattern formed thereon. A method for manufacturing a magnetic recording medium having a magnetically-separated magnetic recording pattern MP, the method at least including; a first step of forming a first magnetic layer 07-22-2010
20100259847PORTABLE APPARATUS HAVING ELECTRONIC CONTROL SYSTEM AND CONTROL METHOD THEREOF - A portable apparatus having an electronic control system and a control method thereof are provided. The portable apparatus comprises an operation system, an accessing device and a basic input/output system (BIOS), and the electronic control system comprises a G-sensor and an embedded controller (EC) for initializing the G-sensor, wherein the G-sensor senses the acceleration of the portable apparatus and compares the acceleration value with the threshold value. The operation system comprises an application program (AP) and an advanced configuration and power interface (ACPI). When the acceleration value is higher than the threshold value, the G-sensor sends out a first signal to the EC, and the EC sends out a second signal to the BIOS, and the BIOS sends out a third signal to the ACPI, and the ACPI sends out a fourth signal to the AP to give a park command for parking the reading head of the accessing apparatus.10-14-2010
20120033323Systems and Methods for Servo Data Based Harmonics Calculation - Various embodiments of the present invention provide systems and methods for servo data based harmonics calculation. For example, a circuit for determining harmonics is disclosed that includes an analog to digital conversion circuit that provides a series of digital samples corresponding to a pattern within a servo data region of a storage medium, and a harmonic calculation circuit. The harmonic calculation circuit is operable to calculate a first harmonic value for the series of digital samples, calculate a second harmonic value for the series of digital samples, and calculate a ratio of the first harmonic value to the second harmonic value.02-09-2012
20100165503METHOD AND APPARATUS FOR RECORDING AND READING INFORMATION - Disclosed are information recording/reading methods. The information recording method includes forming file data and metadata regarding the file data into recording information; dividing a predetermined recording medium into a plurality of zones when a recording mode is set; and recording file data and metadata, which are to be additionally recorded, in different zones.07-01-2010
20100165505POWER SUPPLY VOLTAGE ADJUSTMENT CIRCUIT AND INFORMATION STORAGE DEVICE - According to one embodiment, a power supply voltage adjustment circuit includes a determination module and a voltage controller. The determination module determines whether a head is positioned on a data area specified by a command received from a host based on the relationship between the position of the head and the command. The head reads data from or writes data to an information recording medium. When the head is determined not to be positioned on the data area specified by the command, the voltage controller adjusts a target control value of a power supply voltage supplied to a read channel that exchanges information with the head according to a timing from a time point when a servo mark on the information recording medium is detected.07-01-2010
20110128647METHOD OF DISK ALIGNMENT USING PRINTED ALIGNMENT MARKS - Processes include aligning a disc with a template at a location so that the pattern from the template is transferred to the disc in a relative orientation. The relative orientation provides that when the disc with the transferred pattern is finally assembled into a hard disc drive, an inner diameter of the spindle hole of the disc may be abutted against an outer diameter of the disc drive spindle, and the data-containing patterns on the discs will be aligned concentrically with a center of the disc drive spindle. While the data-containing patterns are aligned concentrically with the disc drive spindle, the substrate itself is allowed to be non-concentric. Still other aspects include a disc having eccentric formations including PIM and one or more of bit patterns and servo information formed on a disc surface, the eccentricity of the formations is determined based on an expected difference between the radius of the spindle hole of the disc and the radius of the spindle on which the disc will be placed during assembly, with the PIM used to determine the angular alignment of the disc with the spindle.06-02-2011
20100002332Optical Path for a Thermal-Assisted Magnetic Recording Head - An optical path or waveguide for a laser-assisted transducing head is disclosed. The optical path extends between the poles of the transducing head to near the write gap. A solid-state laser is attached to or incorporated into the slider or head and is positioned to direct thermal energy through a waveguide and onto a track of a read/write surface to lower the coercivity of the recording medium to facilitate the write process.01-07-2010
20100002331ADAPTIVE SYNCHRONOUS RECTIFICATION OF BRUSHLESS DC MOTOR BACK-EMF - A disk drive power system is described. The system is operable such that during power interruption, the system taps electric power by rectifying the back-EMF generated across each winding of a DC motor and supplying power to a voice-coil motor to park a read/write head safely away from an associated magnetic disk surface.01-07-2010
20100182718Systems and Methods for Adaptive CBD Estimation in a Storage Device - Various embodiments of the present invention provide systems and methods for adaptive channel bit density estimation. For example, various embodiments of the present invention provide methods for adaptively estimating channel bit density. Such methods include providing a storage medium (07-22-2010
20100182715Closed Loop Calibration of Back EMF Measurement - A voice coil motor (VCM) is controlled by applying a bipolar square wave actuator current to the VCM and calibrating a back electromotive force (back-EMF) measurement on the VCM in response to the square wave actuator current. Back-EMF on the VCM is measured while an actuator arm coupled to the VCM is in motion, and the VCM is controlled to move the actuator arm in response to the measured back-EMF voltage.07-22-2010
20100014184POSITION CONTROL APPARATUS AND DISK APPARATUS USING THE SAME - According to one embodiment, a position control apparatus includes: a digital control module that performs position control including disturbance adaptive control with a predetermined sampling period using a control constant, in accordance with a position error; and a table that stores the control constant corresponding to one of values sin(ωT), cos(ωT), and sin(ωT/2), wherein the digital control module determines a control value of the actuator in accordance with the position error, calculates a value of one of estimated errors of sin(ωT), cos(ωT), and sin(ωT/2) according to an adaptive law from a signal based on the position error, multiplies the calculated estimated error by an adaptive gain in accordance with a value of the angular frequency ω, updates one of the values, reads the corresponding control constant from the table based on the updated value, and updates the control constant.01-21-2010
20100188771Magnetoresistive Magnetic Head - A magnetoresistive magnetic head according to one embodiment uses a current-perpendicular-to-plane magnetoresistive element having a laminate of a free layer, an intermediate layer, and a pinned layer, the pinned layer being substantially fixed to a magnetic field to be detected, wherein either the pinned layer or the free layer includes a Heusler alloy layer represented by a composition of X-Y-Z, wherein X is between about 45 at. % and about 55 at. % and is Co or Fe, Y accounts for between about 20 at. % and about 30 at. % and is one or more elements selected from V, Cr, Mn, and Fe, and Z is between about 20 at. % and about 35 at. % and is one or more elements selected from Al, Si, Ga, Ge, Sn, and Sb, the other layer including a high saturation magnetization material layer having higher saturation magnetization than that of the Heusler alloy, and where the direction of the current flowing perpendicular to plane being a direction in which an electron flows from the Heusler alloy layer into the high saturation magnetization material layer. Additional embodiments are also presented.07-29-2010
20100177430Systems and Methods for Fly-Height Control Using Servo Address Mark Data - Various embodiments of the present invention provide systems and methods for determining fly-height adjustments. For example, various embodiments of the present invention provide storage devices that include a storage medium, a read/write head assembly disposed in relation to the storage medium (07-15-2010
20100157466MAGNETIC DISK DEVICE, CONTROL DEVICE AND CONTROL METHOD - According to one embodiment, a magnetic disk device, includes: a magnetic disk; a magnetic head; a writing module configured to write data to a predetermined first track in at least one of the areas by the magnetic head; a reading module configured to read, by using the magnetic head, data of a second track in the at least one of the areas; a first judging module configured to judge whether there is an error in the data read by the reading module; and a first recording module configured to associate and record in a storage module, when the first judging module judges that there is the error in the data of the second track, the at least one of the areas and the number of writing the data to the first track by the writing module.06-24-2010
20100238586ARRANGEMENT METHOD OF SERVO PATTERN OF PATTERNED MEDIUM, PATTERNED MEDIUM, AND INFORMATION STORAGE DEVICE - According to one embodiment, address information is expanded on a bit map in order to generate original address information which is divided in a direction of the abscissa to form groups. The demodulated values of the original address information are obtained as original intra-group demodulated values. New address information is obtained and an arrangement pattern of bits in the servo area determined based on the new address information on a bit map formed by integrating obtained new address information items of the groups.09-23-2010
20100238587PORTABLE DEVICE WITH FREEFALL DETECTION OR AUDIO PROCESSING SUBSYSTEM AND FREEFALL DETECTION OR AUDIO PROCESSING METHOD - In a class of embodiments, a method and apparatus for detecting freefall of a disk device (thereby predicting that the disk device will likely suffer imminent physical impact) and typically also preventing damage that a disk drive of the device would otherwise suffer if and when a predicted impact occurs. In some embodiments, a disk device includes a freefall detection processor and a CPU. The freefall detection processor is configured to monitor acceleration data to determine whether the disk device is in freefall and to perform at least one other operation (e.g., decoding of MP3-encoded audio data to generate decoded audio data) while the CPU performs at least one other task. Other embodiments pertain to a portable device including a digital audio processing subsystem and an accelerometer. The digital audio processing subsystem is configured to monitor acceleration data to identify any rhythm associated with motion of the portable device and to modify the playback of audio data in response to any such identified rhythm.09-23-2010
20100238584SIMULTANEOUS BIT PATTERN DETERMINATION AND HEAD POSITIONAL INFORMATION DETECTION ON PATTERNED MEDIA - An apparatus, system, and method comprise a magnetoresistive head configured to respond to magnetization states of patterned cells formed on a patterned medium. The magnetoresistive head detects the magnetization states of at least two patterned cells formed on a patterned medium. The magnetoresistive head generates a readback signal based on the magnetization state of the at least two patterned cells. A detector circuit coupled to the head determines a bit pattern corresponding to the readback signal. A processor circuit coupled to the detector circuit determines positional information associated with the magnetoresistive head relative to the at least two patterned cells based on the bit pattern. The system further comprises a patterned medium.09-23-2010
20100238585METHOD OF CONTROLLING FLYING HEIGHT OF MAGNETIC HEAD OF HARD DISK DRIVE - A method of controlling an HDD includes acquiring a reference FOD voltage profile offering a correlation between flying heights FH of a magnetic head and FOD voltages that if applied to the magnetic head would cause the head to fly at the flying heights (FH) in an idealized situation, determining changes in the FH of the magnetic head during the rotation of the disk by analyzing magnetic signal output from the magnetic head at that time, producing an applied FOD voltage profile based on the changes in the FH of the magnetic head and the reference FOD voltage profile, and applying and FOD voltage to the magnetic head when a write command or a read command is issued in the HDD and at that time regulating the FOD voltage applied to the magnetic head based on the applied FOD voltage profile to maintain the FH of the magnetic head constant as the head tracks along the disk09-23-2010
20100128381METHOD AND SYSTEM FOR REDUCING POWER CONSUMPTION BY COMMAND SELECTION IN A HARD DISK DRIVE - A system and method for providing a command queue selection scheme by selecting commands by giving preference to commands based on the power consumption characteristics the command. In one embodiment the selection scheme involves calculating the value of the cost of energy saving associated with the access of a command by an evaluation function Costi=EAT+C×F1 (seek distance, latency). C is a dynamically adjustable power control function that determines how much power decreases with the selection of a particular command and F1 is a functional calculation of the power consumption value associated with the particular command. In one embodiment commands with low power consumption will be accessed in preference to commands with shorter seek distance.05-27-2010
20100254038METHOD OF CONTROLLING A FILTER COEFFICIENT OF A CONTINUOUS TIME FILTER AND DATA STORAGE DEVICE THEREOF - A method of controlling a filter coefficient of a continuous time filter of a data storage device is provided. The method of controlling filter coefficient includes positioning a magnetic head at a first reference height from surface of a magnetic disk and outputting a plurality of CSM values by measuring a channel state from a read signal output from the magnetic head when changing a cut-off frequency of the continuous time filter, positioning the magnetic head at a second reference height spaced from the first reference height and measuring a bit error ratio from a read signal output from the magnetic head positioned at the second reference height according to at least one CSM value selected among a plurality of CSM values, and controlling a filter coefficient value to determine a cut-off frequency of the continuous time filter according to a measured bit error ratio.10-07-2010
20110058275DISK DRIVE INCLUDING HEAD-SLIDER CONFIGURED TO SUPPRESS LUBRICANT DROPLET ACCUMULATION - A disk drive. The disk drive includes a disk and a head-slider. The head-slider includes an air-bearing surface. The air-bearing surface includes a trailing-edge rail surface, an inner trailing-edge pad, and an outer trailing-edge pad. The pad surface of the outer trailing-edge pad includes a straight outer edge slanting outward; and, the angle of the outer edge with respect to the longitudinal direction of the head-slider is β03-10-2011
20110058274HARD-DISK DRIVE AND CONTROL METHOD FOR MAGNETIC RECORDING ON A PATTERNED MEDIUM OF THE HARD-DISK DRIVE - A hard-disk drive. The hard-disk drive includes a magnetic-recording disk including tracks on which a plurality of patterned bit-cells that are isolated magnetically are aligned at predetermined alignment pitches. The hard-disk drive includes a magnetic-recording head which is configured to follow tracks, and to write and to read data. The hard-disk drive includes a signal-processing unit which is configured to generate a recording signal based on a write-clock signal with cycles corresponding to alignment pitches of patterned bit-cells, and to output a recording signal. The hard-disk drive includes a phase-detecting unit which is configured to detect a phase of the write-clock signal when the magnetic-recording head reaches an end point of a predetermined range. The hard disk drive includes a determination-processing unit which is configured to determine success of data writing based on a difference between an expected value and a detected value of the phase of the write-clock signal.03-10-2011
20120127605METHOD AND DEVICE FOR MAPPING THE MAGNETIC FIELD OR MAGNETIC FIELD SENSITIVITY OF A RECORDING HEAD - A method and apparatus for scanning a read/write head of a hard disk drive during manufacture are presented. The method includes: providing a magnetic sensor; moving the magnetic sensor relative to and in close proximity to the read/write head under test; obtaining measurements from the head under test or the sensor, representing a two-dimensional magnetic map; processing the map to obtain an accurate map of the head sensitivity of the head under test from which the key performance characteristics of the head can be obtained.05-24-2012
20120127604MAGNETIC RECORDING APPARATUS AND DATA READING METHOD - A magnetic recording apparatus includes: a magnetic disk; a drive device; a magnetic disk control device; a buffer; and a flag management table. The buffer reads data of a specific block unit from a designated read range on the magnetic disk. The flag management table stores a pointer indicating the read location of the buffer for data of each of the block units and a management flag for the pointer. The magnetic disk control device sets the management flag of the pointer corresponding to a given block unit when the data of the given block unit is read to the buffer.05-24-2012
20080231986INFORMATION RECORDING/REPRODUCING DEVICE - An information recording/reproducing device according to an example of the present invention includes a first head and a second head each having a conductive region formed of a conductive material, a recording medium having a data area from which data is read by the first head, and a servo burst area from which a servo burst signal is read by the second head, a driver for positioning the first head and the recording medium based on the servo burst signal, and a resistance element for covering a surface of the conductive region of the second head.09-25-2008
20080231985Magnetic head having two main magnetic poles, magnetic disk apparatus and magnetic head switching control circuit - A magnetic head structure is disclosed which can avoid the problem of side erasing regardless of whether the skew angle is assigned to the positive side or negative side while ensuring write magnetic field intensity. The magnetic head includes at least two main magnetic poles having a single taper shape as a plane shape of a tip thereof opposite to a recording medium and axially symmetrically disposed with respect to a longitudinal direction of a slider, a return yoke for returning a write magnetic field generated by the main magnetic poles, and thin-film coils assigned to each of the main magnetic poles.09-25-2008
20090116137Perpendicular magnetic recording medium and magnetic storage apparatus using the same - Embodiments of the present invention provide a perpendicular magnetic recoding medium capable of decreasing exchange coupling between crystal grains while suppressing increase in the crystal grain size of the magnetic recording layer. According to one embodiment, a perpendicular magnetic recoding medium is formed by stacking a seed layer, an intermediate layer, a magnetic recording layer, and a protecting layer all above a substrate. The magnetic recording layer has a granular structure constituted of a plurality of columnar grains comprising a CoCrPt alloy and a grain boundary containing an oxide. The seed layer is formed by stacking a first seed layer, a second seed layer, and a third seed layer in which the first seed layer comprises Ti or Ti alloy having a hexagonal close-packed structure, the second seed layer comprises Cu, Ag, or Al having a face-centered cubic structure or an alloy containing at least one element selected therefrom, and the third seed layer comprises an Ni alloy having a face-centered cubic structure.05-07-2009
20110176239Head stack assembly and disk drive unit with the same - Disclosed is a head stack assembly, which comprises a pivot bearing assembly having a main body which comprising a first end surface and a second end surface, and a flange extended from the main body and located between the first and second end surfaces, the flange having a first interface adjacent the first end surface of the main body and a second interface opposite to the first interface; a drive arm mounted on the main body and secured on the first interface of the flange; and a fantail spacer mounted on the main body and secured on the second interface of the flange.07-21-2011
20100033868METHOD FOR WRITING SERVO PATTERNS AND DISK DRIVE INCLUDING A CONTROLLER FOR WRITING SERVO PATTERNS ACCORDING TO THE METHOD - A method for writing servo patterns onto a disk of a disk drive. The method includes providing a plurality of different drive currents for an actuator while pushing the actuator into a crash stop defining a swing range of the actuator. The method also includes performing a write operation for at least one of the plurality of different drive currents to write a plurality of servo pattern tracks including a plurality of separate servo pattern sectors. Furthermore, the method includes gradually changing a drive current of the plurality of different drive currents while pushing the actuator into the crash stop so as to gradually move a read element in searching for a servo pattern track to a radial position different from a radial position of the write element. Moreover, the method includes positioning the read element at one of the plurality of servo pattern tracks.02-11-2010
20120194944DISK DEVICE - According to one embodiment, a disk device rotates a disk information storage medium to record and reproduce information on the information storage medium by use of a head that slides in contact with a lubricant coated on the information storage medium, wherein a sliding speed U, area A and normal force N are set to cause U×A/N to fall within a monotonously increasing region in which a coefficient of friction associated with a frictional force occurring in a contact area of the head that faces the information storage medium monotonously increases as U×A/N increases, where the sliding speed U represents a sliding speed at a sliding time of the head, the area A represents the contact area of the head, and the normal force N represents a normal force applied to the contact area of the head.08-02-2012
20090116139Hard disk drive protection system and method - A hard disk drive protection system comprises a sensor configured to detect an impending shock event and a hard drive protection module configured to determine whether to issue a fast park command for a hard disk drive in response to detecting the impending shock event based on a permissible quantity of fast park cycles for the hard disk drive.05-07-2009
20090116138Disk drive and controlling method thereof - Embodiments of the present invention provide a disk drive capable of appropriately measuring non-linearity in a head position control system, and a control method therefor. According to one embodiment, a magnetic disk drive inputs a reference signal S05-07-2009
20090116136VIBRATION DETECTION AND COMPENSATION FILTER - The application relates to an adaptive vibration damping scheme that provides for detection of, and adjustment for, vibration-related disturbances in devices. The vibration damping scheme utilizes a common filter function to implement vibration detection and vibration compensation.05-07-2009
20090116135HEAD POSITIONING ASSEMBLY - A head positioning assembly having a first carriage assembly, a second carriage assembly, and an actuator. The second carriage assembly has a head and is coupled to the first carriage assembly by a first flexible member. The first and second carriage assemblies may be actuated to position the head when sufficient force is provided by the actuator.05-07-2009
20090244765PATTERNED MEDIA MAGNETIC RECORDING DISK DRIVE WITH WRITE CLOCK PHASE ADJUSTMENT FOR DATA PATTERN CIRCUMFERENTIAL MISALIGNMENT - A patterned-media magnetic recording disk drive compensates for circumferential misalignment of data island patterns among the data tracks as a result of errors in fabrication of the master template used to make the disks. Each data track on the disk has its pattern shifted from a generally radial or arcuate line by a certain amount of pattern circumferential misalignment (PCM). The disk drive includes a write clock where writing to the data islands is controlled by detection of synchronization marks by the read head, and circuitry to adjust the phase of the write clock to compensate for PCM. The phase difference between the data pattern of the selected data track where data is to be written and the data pattern of the track where the synchronization marks are being detected is the difference in their respective PCM values.10-01-2009
20090190249Method and apparatus for efficient storage and retrieval of multiple content streams - Embodiments of the present invention provide disk controller operable to facilitate the efficient storage and retrieval of multiple content (data) streams to magnetic disk media. This disk controller includes an interface module, a memory module, and a processing module. The interface module is operable to couple the disk controller to a hard disk drive. The memory module and processing module in combination are operable to execute instructions that detect the geometry associated with the hard disk drive. Then the disk controller is operable to determine when the hard disk drive geometry supports assigning unique RW heads to unique content (data) streams. When the hard disk geometry supports assigning unique RW heads to unique content (data) streams, RW heads may be preferentially reserved or assigned to unique content streams wherein the RW heads are able to write unique content streams to memory locations within the hard disk drive, wherein these memory locations may be contiguous or near contiguous.07-30-2009
20130128380METHODS AND DEVICES FOR COMPENSATING FOR OFF-TRACK MOTION - In certain embodiments, a method includes sensing a mode of a motor-base assembly's response to vibration. Based on the sensed response, the method includes adjusting a head-suspension assembly to compensate for off-track motion caused by the vibration.05-23-2013
20130128381MAGNETORESISTIVE HEAD HAVING PERPENDICULARLY OFFSET ANISOTROPY FILMS AND A HARD DISK DRIVE USING THE SAME - In one embodiment, a magnetic head includes a lower shield layer, a sensor stack positioned above the lower shield layer, the sensor stack including a free layer, a layered hard bias magnet positioned above the lower shield layer and on both sides of the sensor stack in a track width direction, and an upper shield layer positioned above the hard bias magnet and the sensor stack. The hard bias magnet includes a perpendicular anisotropy film positioned above the lower shield layer and aligned with both sides of the sensor stack in the track width direction, wherein the perpendicular anisotropy film directs magnetic fields in a direction perpendicular to planes of formation thereof, and an in-plane anisotropy film positioned above the perpendicular anisotropy film, wherein the in-plane anisotropy film directs magnetic fields in a direction of planes of formation thereof.05-23-2013
20110128648METHOD AND APPARATUS FOR CONTROLLING HEAD WITH SPIN-TORQUE OSCILLATOR IN A DISK DRIVE - According to one embodiment, an apparatus for controlling a head includes a transmitting module and a controller. The transmitting module is configured to transmit a write signal to a magnetic head having a spin torque oscillator at the time of recording data. The controller is configured to supply a drive signal that has a level higher than the ordinary level for a prescribed effective time, to the spin-torque oscillator in response to an input write gate that instructs the recording of data. During a period other than prescribed effective time, the controller supplies a drive signal having the ordinary level to the spin-torque oscillator.06-02-2011
20100302674APPARATUS AND METHOD FOR STABILIZING SLIDER FLYING HEIGHT OVER A DISCRETE TRACK MEDIA DISK SURFACE IN A HARD DISK DRIVE - This application discloses a hard disk drive and a disk employing Discrete Tracks each including a land with a groove at a first depth with sectors of each track separated by servo pattern wedges with a variable second land and a variable second groove possessing widths and a second depth for the grooves differing from the first widths and depth of the groove of the sectors. The second depth optimizes the stability of the flying height of a slider over both sectors and servo pattern wedges, removing the possibility of added vibrational modes adversely affecting the slider's normal operations of reading, writing and flying above the disk surface. This also discloses the disks and their manufacture of disk surfaces with these sector zones and servo pattern wedges.12-02-2010
20110122526MANUFACTURING METHOD OF MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING MEDIUM, AND INFORMATION STORAGE DEVICE - A manufacturing method of a magnetic recording medium includes: forming a magnetic film having an artificial lattice structure by laminating plural types of atomic layers alternately on a substrate; and separating dots, which forms a dot separation band by implanting an ion, to reduce saturation magnetization locally, into portions of the magnetic film other than plural portions of the magnetic film. Each of the plural portions is made into a magnetic dot in which information is to be magnetically recorded. The saturation magnetization of the dot separation band is smaller than that of the magnetic dot.05-26-2011
20110128646SYNCHRONIZED REWRITING OF DATA - A hard disk drive (HDD) including a magnetic disk, the magnetic disk including a data track. The HDD also includes a synchronized rewrite controller for synchronizing a plurality of rewrites of a data pattern on a location of the track of the magnetic disk and the HDD includes a write head controlled by the synchronized rewrite controller for writing the data pattern on the location of the data track and rewriting the data pattern a plurality of times on the location in synchronization with a prior writing of the data pattern on the data track.06-02-2011
20110002063PERPENDICULAR MAGNETIC RECORDING HEAD AND MAGNETIC RECORDING DEVICE SUITABLE FOR HIGH-DENSITY MAGNETIC RECORDING - According to one embodiment, a perpendicular magnetic recording head includes a main magnetic pole having a trailing side and two lateral sides, a magnetic shield near the trailing side and both lateral sides of the main magnetic pole, the magnetic shield comprising: a first soft magnetic film with a relatively high saturation flux density positioned facing depthwise from a floating surface side thereof, a second soft magnetic film with a relatively low saturation flux density, and a first non-magnetic film. The head also includes a non-magnetic film interposed between the magnetic shield and the main magnetic pole, a first magnetic film magnetically coupled to the magnetic shield and the main magnetic pole on a side opposite a floating surface side thereof, and a coil surrounding a magnetic circuit, the magnetic circuit comprising the main magnetic pole and the first magnetic film. Other systems and methods are also described.01-06-2011
20110002064PERPENDICULAR MAGNETIC RECORDING MEDIUM (PMRM) AND MAGNETIC STORAGE DEVICE USING THE SAME - According to one embodiment, a PMRM includes a substrate, a soft magnetic underlayer above the substrate, an underlayer above the soft magnetic underlayer, an oxide-containing magnetic layer above the underlayer, and a ferromagnetic layer above the magnetic layer having no oxides. The underlayer controls orientation and segregation of the magnetic layer. The oxide-containing magnetic layer comprises at least two or more magnetic layers, a Cr concentration of the magnetic layer adjacent to the ferromagnetic metal layer is between about 23 at. % and about 32 at. %, and a difference between the Cr concentration of the magnetic layer adjacent to the ferromagnetic metal layer and a magnetic layer having a lowest Cr concentration among the at least three magnetic layers is less than about 25 at. %, the magnetic layer with a lowest Cr concentration has a granular structure, and a nucleation field is greater than about 159.2 kA/m.01-06-2011
20110026158METHODS AND DEVICES TO CONTROL WRITE POLE HEIGHT IN RECORDING HEADS - Recording heads for data storage systems are provided. Recording heads illustratively include a write pole, a bumper, a dielectric layer, and a surface. In some embodiments, a portion of the surface includes portions of the write pole, bumper, and dielectric layer. The write pole, bumper, and dielectric layer are illustratively made from materials that have polishing rates. In some embodiments, the polishing rate for the write pole material is more similar to the polishing rate for the bumper material than it is to the polishing rate for the dielectric layer material.02-03-2011
20110026159DISK DRIVE BIASING REFRESH ZONE COUNTERS BASED ON WRITE COMMANDS - A disk drive is disclosed comprising a disk comprising a plurality of tracks, and a head actuated over the disk. A plurality of refresh zones are defined, wherein each refresh zone corresponds to a plurality of the tracks. Data is written to a first refresh zone, and a first zone counter is updated for a second refresh zone at a first rate. Data is written to a third refresh zone, and the first zone counter is updated for the second refresh zone at a second rate different than the first rate.02-03-2011
20110249361FLY-HEIGHT CONTROL USING ASYNCHRONOUS SAMPLING - In one embodiment, a hard-disk drive system performs fly-height control using a read-back mode and a loop-back mode. The read-back mode measures first and second harmonics pre-recorded on the medium and divides the first measurement by the second to obtain a read-back mode harmonic ratio. The loop-back mode measures the same first and second harmonics; however, the harmonics are provided by a write precompensation circuit rather than the medium. Further, the loop-back mode measurements are performed using asynchronous sampling to address aliasing and quantization errors. The first measurement is divided by the second to generate a loop-back harmonic ratio. In logarithm domain, the loop-back ratio is subtracted from the read-back mode ratio to remove environment-induced variations in the read path electronic circuits. The resulting harmonic ratio is subtracted from an initial harmonic ratio determined, for example, during manufacturing, to determine how much the harmonic ratio has changed.10-13-2011
20110249359MAGNETIC HEAD HAVING AN ASYMMETRICAL SHAPE AND SYSTEMS THEREOF - A magnetic head, according to one embodiment, includes a main magnetic pole having a protruding portion such that a distance from a first side of a trailing edge of the main magnetic pole to a leading edge of the main magnetic pole is different from a distance from a second side of the trailing edge of the main magnetic pole to the leading edge of the main magnetic pole, an auxiliary magnetic pole, and a coil wound around a magnetic circuit, the magnetic circuit including the main magnetic pole and the auxiliary magnetic pole. In another embodiment, a disk drive system includes a magnetic storage medium, at least one magnetic head as described previously for writing to the magnetic medium, a slider for supporting the magnetic head, and a control unit coupled to the magnetic head for controlling operation of the magnetic head. Additional systems and heads are also presented.10-13-2011
20090067083HARD DISK DRIVE CONTROLLER, IMAGE FORMING APPARATUS AND STORAGE MEDIUM WITH RECORDED COMPUTER PROGRAM - A hard disk drive controller including a determining unit that determines an external dimension of a hard disk drive that is provided with a motor for rotating a hard disk and a head that is retractable from the hard disk; and a changing unit that changes control of the hard disk drive device according to the external dimension that has been determined by the determining unit. An image forming apparatus is also disclosed which includes the determining unit, the changing unit, and an energy saving shifting unit that shifts the image forming apparatus into an energy saving mode in certain conditions which have been determined in advance. A storage medium on which a program for execution on a computer is stored, the program having the function of the determining unit and the function of the changing unit, is also disclosed.03-12-2009
20090067084Method for establishing and maintaining radial position for hard disk drive self servo write without seed wedges - Magnetic reference patterns may be generated on a disk or other magnetic media without the need for seed wedges. This involves writing a first magnetic reference pattern to the disk with a servo writer. The disk may then be transferred to a hard disk drive. Control circuitry within the hard disk drive may recognize the first magnetic reference pattern and then position a RW head within the hard disk drive based on the first magnetic reference pattern. As the RW drive is accurately positioned based on the first magnetic reference pattern a second magnetic reference pattern may be written to the disk using the RW head. The RW head location is determined based on the velocity and phase between the read-write head and spiral sync marks contained within the first magnetic reference pattern.03-12-2009
20100079900MAGNETIC HEAD-POSITIONING SERVO SYSTEM, MAGNETIC HEAD TEST SYSTEM AND MAGNETIC DISK TEST SYSTEM - A magnetic head-positioning servo system is provided to accurately test a magnetic disk with a track written in advance, by providing two fine actuators. The second fine actuator, to which a magnetic head is attached, is mounted on the first fine actuator. The second fine actuator has a larger generating displacement than a generating displacement of the first fine actuator, and lets the magnetic disk to follow the eccentricity of the track. In this way, the positioning accuracy can be increased.04-01-2010
20110032635MAGNETIC RECORDING MEDIUM AND METHOD FOR MANUFACTURING THE SAME, AND MAGNETIC RECORDING REPRODUCING APPARATUS - A magnetic recording medium of the present invention includes, on a substrate (02-10-2011
20110116186Adjusting Recording Density in a Circumferential Direction - Approaches for adjusting the recording density of a recording medium in a circumferential direction are disclosed. A hard-disk drive includes one or more electronic components configured to divide a track, of a plurality of concentric tracks on a magnetic-recording disk, into a plurality of portions, and write data to each of the plurality of portions at a recording density that is independent of the recording density used for any of the other portions. Data may be written to a first portion of a track at a different frequency than to a second portion of the same track. The frequency at which data is written may be adjusted for different portions of the same track to allow the frequency to be reduced at certain portions shown to have relatively higher soft error rate while increasing the frequency for other portions to achieve a desired average error rate for the track.05-19-2011
20110242698Barium Ferrite Magnetic Storage Media - Magnetic storage media that include a multilayer structure are described. In general, the magnetic storage media include a substrate, an underlayer that includes a plurality of underlayer particles formed over the substrate, and a magnetic layer that includes a plurality of magnetic particles formed over the underlayer. The magnetic layer may define a saturated magnetization and thickness product less than or equal to approximately 1.00 memu per square centimeter, and the magnetic particles may be selected from the group consisting of magnetic platelet-shaped particles and magnetic particles with an aspect ratio less than or equal to approximately 1.5. In addition, the described magnetic storage media may exhibit minimal interlayer diffusion between the underlayer and magnetic layer. Reduced interlayer diffusion between different layers of a magnetic recording medium may result in an improved magnetic recording surface for recording and storing data.10-06-2011
20090034113Disk device and electronic equipment using the same - It is equipped with a magnetic recording medium, a spindle motor which rotates the magnetic recording medium, ahead portion which carries out at least any one of recording and reproducing of information, an actuator which supports the head portion, a voice coil which turns the actuator, a relay wiring body which is electrically connected to the head portion and the voice coil, and a motor wiring body which is electrically connected to the spindle motor, and a housing is equipped with a connector by which the relay wiring body and the motor wiring body are electrically connected in the housing for giving and receiving an electric signal between the relay wiring body and the motor wiring body and a control section.02-05-2009
20110128649MAGNETIC RECORDING MEDIUM HAVING NON-MAGNETIC SEPARATING REGIONS AND METHODS OF MANUFACTURING THE SAME - In one embodiment, a magnetic recording medium includes a patterned magnetic recording layer above a substrate, the patterned magnetic recording layer including recording regions and separating regions for separating the recording regions and a non-magnetic alloy layer positioned in the separating regions, wherein the non-magnetic alloy layer includes Ti. In another embodiment, a method for producing a magnetic recording medium includes forming separating regions in a magnetic recording layer by removing portions of the magnetic layer, wherein the separating regions separate recording regions in the magnetic layer, and depositing a non-magnetic alloy layer in the separating regions. Other media and methods are described according to more embodiments.06-02-2011
20110242700METHOD OF PRODUCING MAGNETIC STORAGE MEDIUM, MAGNETIC STORAGE MEDIUM AND INFORMATION STORAGE DEVICE - The following abstract replace prior abstract in the application. It is an object to provide a simple and practical method capable of producing a magnetic storage medium of a type such as a bit-patterned type, a magnetic storage medium of the above-mentioned type and an information storage device which may be produced by such a simple and practical method, and in a method of producing a magnetic disk, there are performed: a film-forming process of forming, on a glass substrate 10-06-2011
20090080106Magnetic head and magnetic recording device - It is made possible to restrict the variation of the oscillation frequency of a spin torque oscillator placed in the vicinity of the recording magnetic pole. A magnetic head includes: a recording magnetic pole to generate a recording magnetic field; a spin torque oscillator formed in the vicinity of the recording magnetic pole; and a magnetic field applying unit configured to apply a magnetic field to the spin torque oscillator. The magnetic field applied to the spin torque oscillator by the magnetic field applying unit is perpendicular to a recording magnetic field generated from the recording magnetic pole.03-26-2009
20110242699HARD DISK CONTROL MODULE, APPARATUSES HAVING THE SAME, AND METHOD OF CONTROLLING UNLOAD STANDBY TIME THEREOF - A hard disk control module includes a load/unload counter and a controller. The load/unload counter counts a number of loads/unloads of a head on/from a surface of a disk. The controller may determine the number of counted loads/unloads during a reference time. The controller controls an unload standby time of the head according to a load/unload count value and the reference time.10-06-2011
20100188772METHOD FOR MANUFACTURING MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS - There are provided a method for manufacturing a magnetic recording medium which is excellent in terms of both the recording and reproduction characteristics and the thermal fluctuation characteristics without reducing the density and hardness of the perpendicular magnetic layer; a magnetic recording medium; and a magnetic recording and reproducing apparatus with which an excellent recording density is achieved,07-29-2010
20100014187READ/WRITE APPARATUS AND METHOD FOR A MAGENTIC STORAGE MEDIUM COMPRISED OF MAGNETIC NANOPARTICLES CONTAINED WITHIN CARBON NANOTUBES - A magnetic storage medium is formed of magnetic nanoparticles that are encapsulated within carbon nanotubes, which are arranged in a substrate to facilitate the reading and writing of information by a read/write head. The substrate may be flexible or rigid. Information is stored on the magnetic nanoparticles via the read/write head of a storage device. These magnetic nanoparticles are arranged into data tracks to store information through encapsulation within the carbon nanotubes. As carbon nanotubes are bendable, the carbon nanotubes may be arranged on flexible or rigid substrates, such as a polymer tape or disk for flexible media, or a glass substrate for rigid disk. A polymer may assist holding the nano-particle filled carbon-tubes to the substrate. Magnetic fields may be applied to draw the carbon nanotubes into data tracks and orient the carbon nanotubes within the data tracks. Read/write devices and methods create servo sectors and rotational markers on the magnetic storage medium as well as data.01-21-2010
20090257146MAGNETIC DISC APPARATUS AND TRACK FOLLOWING METHOD - A disclosed magnetic disc apparatus includes a magnetic disc medium including a first part and a second part having light reflection different from light reflection of the first part; a head having a first device for detecting reflectivity on the magnetic disc medium and a second device for performing magnetic recording/playback on the magnetic disc medium; and a positioning unit configured to determine, based on the reflectivity on the magnetic disc medium detected by the first device, a position for the magnetic recording/playback performed by the second device on the magnetic disc medium.10-15-2009
20090257145CONTROL CIRCUIT AND INFORMATION STORAGE DEVICE - A information storage device has a head slider having a flying height control mechanism and a recording and reproducing head, a low frequency superposed circuit that superimposes a low frequency voltage to a flying height adjustment signal to adjust the flying height of the head slider, and a polarity discrimination section that discriminates the polarity of the low frequency detection signal to the low frequency voltage through comparison of the low frequency voltage with the low frequency detection signal. When the polarity of the low frequency detection signal to the low frequency voltage is a negative polarity, the flying height adjustment signal is subtracted by a predetermined value, so that the flying height of the head slider is increased by the correspondence.10-15-2009
20100027153THIN FILM PLANAR ARBITRARY GAP PATTERN MAGNETIC HEAD - Planar magnetic heads and methods of making the same using a built-up approach and thru-hole via technology to achieve a true planar head. A head may comprise a substrate having conductive thru-hole vias extending therethrough, a first magnetic layer deposited and patterned on the substrate, a first insulation layer deposited and patterned on the first magnetic layer, a conductive coil layer deposited and patterned on the first insulation layer and connected to the conductive thru-hole vias, a second insulation layer deposited and patterned on the conductive coil layer, vias patterned into the insulation layer extending to the first magnetic layer, a second magnetic layer deposited in the vias, and a third magnetic layer deposited and patterned on the second insulation layer and second magnetic layer. The third magnetic layer may be connected to the first magnetic layer through the second magnetic layer deposited in the vias of the insulation layers.02-04-2010
20100053797METHOD FOR MANUFACTURE OF MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING AND REPRODUCTION DEVICE - A method for manufacturing a magnetic recording medium includes the steps of depositing a magnetic layer on at least one of surfaces of a nonmagnetic substrate and injecting atoms partially in the magnetic layer, thereby demagnetizing parts having admitted the injected atoms or imparting amorphousness thereto, to form a magnetically separated magnetic recording pattern. The step of injecting includes the steps of applying resist to the at least one surface subsequent to the step of depositing, partially decreasing a thickness of the resist and irradiating a surface of the resist with atoms, thereby inducing partial injection of the atoms to the magnetic layer through portions of the resist decreased in thickness.03-04-2010
20090034114Magnetic disk drive with head retraction control - Embodiments of the invention improve utility of a magnetic disk drive in which a head is retracted if the magnetic disk drive is in a dropping state. In one embodiment, an HDC/MPU provided in a magnetic disk drive judges whether the magnetic disk drive is in a dropping state based on an output from an acceleration sensor which may detect an acceleration and performs a retraction operation of a head. After the HDC/MPU judges that a drop is occurring, the HDC/MPU detects whether the drop judgment is incorrect according to whether a shock sensor detects a shock occurrence and changes the drop judgment condition based on a detection history of detected incorrect judgments.02-05-2009
20100053796DISK DRIVE INCLUDING A DELAY CIRCUIT TO PROVIDE A DELAYED RESET SIGNAL - A disk drive including a delay circuit to provide a delayed reset signal is disclosed. The disk drive includes a head to perform write and read operations to and from a disk and a disk controller that is coupled to the head to control the write and read operations performed by the head. The disk drive further includes: a power loss detection circuit to detect a power loss and to generate a reset signal in response to the power loss; a reset power line coupled to the disk controller and the power loss detection circuit to provide a non-delayed reset signal to the disk controller; and a delay circuit coupled to the reset power line wherein the delay circuit delays the reset signal to provide a delayed reset signal.03-04-2010
20100134916MAGNETIC RECORDING MEDIUM AND MAGNETIC STORAGE DEVICE - According to one embodiment, a magnetic recording medium includes a disc substrate, a first recording layer, and a second recording layer. The first recording layer is disposed in at least one of a plurality of data storage areas partitioned in a radial direction on the disc substrate. A magnetic material is deposited on the first recording layer. The second recording layer is disposed in the data storage areas except the data storage area where the first recording layer is disposed. The second recording layer includes a magnetic material and a non-magnetic material that are alternately arranged in the in-plane direction of the upper surface of the disc substrate.06-03-2010
20090027800STORAGE APPARATUS, CONTROL METHOD AND CONTROL UNIT - According to an aspect of an embodiment, a storage apparatus includes a judgment unit which judges the clearance between a head and a recording medium. A mode switcher switches from a regular write mode in which data is written on the medium to a write verification mode in which error is checked by reading the data immediately after writing on the medium, where the judgment unit detects a clearance change. A heater control value adjustor corrects for errors detected in the write verification mode by changing a prescribed heater control value for the heater by executing write verifications. An access processor controls the clearance between the head and the medium by heating the head according to the adjusted heater control value, to compensate for operational variables such as low atmospheric pressure.01-29-2009
20090027799DISK DRIVE REFRESHING ZONES IN SEGMENTS TO SUSTAIN TARGET THROUGHPUT OF HOST COMMANDS - A disk drive is disclosed including a disk comprising a plurality of refresh zones, and a head actuated over the disk. The disk drive further comprises control circuitry for receiving access commands from a host. The control circuitry refreshes a refresh zone in a plurality of segments with an interval between each segment, and processes at least one of the access commands during the interval between at least two of the segments, wherein a size of each segment and the interval ensures an average throughput of access commands received from the host does not fall below a first threshold.01-29-2009
20120120521CONTACT DETECTION BETWEEN A DISK AND MAGNETIC HEAD - A HDD including a magnetic disk, a magnetic head, an embedded contact sensor embedded in the magnetic head and configured to detect a contact between the magnetic disk and the magnetic head, and TFC embedded in the magnetic head and configured to facilitate in detecting the contact between the magnetic disk and said magnetic head.05-17-2012
20110069410MAGNETIC-RECORDING-DISK TEST-HEAD AND METHOD OF MANUFACTURING A MAGNETIC-RECORDING DISK USING THE MAGNETIC-RECORDING-DISK TEST-HEAD - A magnetic-recording-disk test-head. The magnetic-recording-disk test-head includes a slider, a test pad and a slider-surface-shape control mechanism. The slider includes a leading edge and a trailing edge. The test pad is disposed at a trailing-edge side of the slider and is configured to remove and to detect asperities on a magnetic-recording disk. The slider-surface-shape control mechanism is configured to change a shape of an air-bearing surface of the slider and is disposed at a leading-edge side of the slider.03-24-2011
20110075291DISK DRIVE CONTROLLED TO DETECT HEAD-DISK INTERFERENCE - A disk drive comprises a disk, and a head for reading and writing data on the disk. The disk drive detects head-disk interference (HDI) during a write operation by measuring a parameter during the write operation and comparing the measured parameter against a reference parameter. The reference parameter is measured while the disk drive generates HDI under a set of reference conditions. In various embodiments, the reference parameter comprises attributes of a position error signal, a servo automatic gain control, a jitter representing a difference between a current velocity and a target velocity of a spindle motor, and a bias applied to a voice coil motor.03-31-2011
20110043944JERK DETECTION FOR DATA STORAGE DEVICE - A device comprising at least one sensor configured to sense disturbances applied to the data storage device and to generate signals based on the sensed disturbances, and a controller configured to receive the signals from the at least one sensor and to detect jerk events in the sensed disturbances based at least in part on vector differentials of the received signals.02-24-2011
20110211275Method of determining flying height of magnetic head - For obtaining a flying height of a magnetic head from a magnetic disk, the magnetic head being placed in a slider arranged at an interval with the magnetic disk, an initial setting process and a flying height detecting process are performed. In the initial setting process, driving power to a heater is increased gradually, from a state where the heater arranged at a position in proximity to the magnetic head in the slider is not driven, until the magnetic head makes contact with the magnetic disk. Then, in each stage, an electrical resistance value of the sensor arranged at a position in proximity to the magnetic head in the slider, which is increased due to the heat from heater, and either an approach distance of the magnetic head toward the magnetic disk or the flying height of the magnetic head from the magnetic disk are acquired. Then, basic data is prepared by obtaining the relationship between a variation of the electrical resistance value of the sensor and the flying height of the magnetic head from the magnetic disk, which is obtained in each stage or which calculated from the approach distance in each stage. In the flying height detecting process, an electrical resistance value of the sensor is determined, and a variation of the electrical resistance value is calculated from the determined values. Then, the flying height of the magnetic head from the magnetic disk in the state where the electrical resistance value was determined is obtained based on the basic data obtained in the initial setting process, using the calculated variation of the electrical resistance value.09-01-2011
20100277826HEAD RADIAL POSITIONING OVER CONTACT-START-STOP ZONE DURING SPIN-UP/SPIN-DOWN OF DISK - A read/write head is moved across a contact-start-stop (CSS) zone on a data storage disk during the spin-up and/or spin-down of the disk. Moving the head during spin-up and/or spin-down may reduce the concentration of wear along a surface of the CSS zone.11-04-2010
20100259848METHOD AND CIRCUIT FOR HEAD FLYING HEIGHT CONTROL, AND MAGNETIC STORAGE DEVICE - According to one embodiment, there is provided a head flying height control method for controlling a flying height of a magnetic head from a magnetic storage medium. The magnetic head includes an element portion and a heater that effects a change in a protrusion amount of the element portion due to thermal expansion accompanying heat generation. The head flying height control method includes: causing the element portion to protrude a maximum protrusion amount by increasing a heater power of the heater; first-reducing the heater power based on a relation between the protrusion amount and the heater power until the protrusion amount becomes a predetermined protrusion amount; and second-reducing, if a head-medium property is better than a target value after the first-reducing, the heater power based on a relation between the head-medium property and the heater power so that the head-medium property matches the target value.10-14-2010
20100118433WRITE PRECOMPENSATION SYSTEM - A write precompensation system comprises a write precompensation processor that calculates time shift information for the timing of individual write current transitions at a write head to coincide with a media pattern under the write head and a write precompensation controller that shifts the individual write current transitions in accordance with the time shift information.05-13-2010
20120147494POWER-SUPPLY DEVICE, AND LED LIGHTING EQUIPMENT AND HARD DISK DRIVE USING THE SAME - A power supply device includes two buck converters, having a coupling inductor Lo composed of two mutually-coupled inductors L06-14-2012
20110249360PERPENDICULAR MAGNETIC RECORDING HEAD - According to one embodiment, a perpendicular magnetic recording head includes a main magnetic pole including a write magnetic pole layer for recording, the write magnetic pole layer comprising magnetic layers being antiferromagnetically coupled via a thin non-magnetic conductor layer between the magnetic layers, wherein the write magnetic pole layer for recording has a flare section which gradually widens in a height-wise direction of a throat height section. The main magnetic pole also includes a non-magnetic cap layer laminated above an uppermost layer of the write magnetic pole layer, the non-magnetic cap layer being textured to provide anisotropy, and a subsidiary magnetic pole layer for supplementing the recording laminated above the non-magnetic cap layer. The head also includes an auxiliary magnetic pole, a magnetic shield positioned via a non-magnetic layer on a trailing edge and both sides of the main magnetic pole in a track width direction, and a coil for generating a recording magnetic field.10-13-2011
20100033866MULTI-SPEED STORAGE DEVICE - Various embodiments of the present invention are generally directed to adjusting a fly height of a transducer to enable a first data access with a storage medium rotating at a first speed, rotating the storage medium at a second speed substantially different from the first speed, and adjusting the fly height of the transducer to enable a second data access with the storage medium rotating at the second speed.02-11-2010
20120200953MAGNETIC DISC APPARATUS - According to one embodiment, a magnetic disc apparatus includes a magnetic head which reads information stored in a magnetic disc, an arm which supports the magnetic head, and a feedback controller which controls a coarse actuator to move the magnetic head above the magnetic disc by driving the arm, a fine actuator to hold a position of the magnetic head, and a feedback path which feeds back a displacement of the actuator to a target value of the coarse actuator. The feedback controller controls decoupling of a double actuator system which adds up the coarse actuator and the fine actuator.08-09-2012
20120268841SUSPENSION FOR COMPENSATING SLIDER ATTITUDE - Disclosed is an assembly located in a memory device. The assembly includes: a suspension including a flexure to which a slider is coupled and a load beam disposed at an upper part of the flexure The assembly also includes at least one piezoelectric film coupled to the suspension and configured to control at least one of an angle between the load beam and the flexure in a pitching direction and an angle between the load beam and the flexure in a rolling direction by being extended or contracted when electrical current is applied thereto.10-25-2012
20110255189METHOD OF DETECTING TOUCHDOWN OF MAGNETIC HEAD USING TIMESTAMPS, AND MAGNETIC DISK DRIVE TO WHICH THE METHOD IS APPLIED - According to one embodiment, a method of detecting contact of a magnetic head with a magnetic disk by changing the dynamic flying height of the magnetic head in a magnetic disk drive is disclosed. The method can detect a change in the rotational speed of the magnetic disk. The method can detect the contact of the magnetic head with the magnetic disk based on the detected change in the rotational speed.10-20-2011
20080247079Disk drive and control method thereof - Embodiments in accordance with the present invention reduce the number of errors caused by the aged deterioration of a heater for adjusting the clearance between a head and a disk. According to one embodiment, a thermal fly height control (TFC) controller executes the measurement of a resistance value of a heater in a predetermined timing. The TFC controller judges whether or not the measured resistance value falls within a predetermined reference range. If the measured resistance value falls within the reference range, the processing ends without performing any other processing. If the measured resistance value goes out of the reference range, the TFC controller executes error handling processing in response to a resistance failure. As one of the error handling processing, the TFC controller notifies the host that the abnormality (resistance failure) has been detected in the resistance value of the TFC heater.10-09-2008
20080316636DISK DRIVE IN WHICH DYNAMIC FLY HEIGHT OF HEAD IS ADJUSTED, AND METHOD OF ADJUSTING THE DYNAMIC FLY HEIGHT OF THE HEAD - According to one embodiment, a disk drive includes a heating element which is provided on a head and generates heat when supplied with power, thereby to adjust a dynamic flying height of the head. A head-movement detecting unit detects the abnormal movement of the head, a value of which is larger than a preset movement value during a head positioning control. In this case, a heating-element controller stops supplying power to the heating element.12-25-2008
20080291563Torsion compensation coil for voice coil motor of disk drive device, and method of making the same - Certain example embodiments relate to torsion compensation coils that cooperate with primary coils in voice coil motors of disk drive devices, and methods of making the same. In certain example embodiments, a voice coil motor is provided which may include a single external magnet. A primary coil may be located above the external magnet, with the primary coil being capable of receiving a first current. At least one torsion compensation coil may be connected to the primary coil. The at least one torsion compensation coil may be capable of receiving a second current. The at least one torsion compensation coil may be configured to reduce torsion and/or bending forces introduced by the first current passing through primary coil and/or magnetic field leakage from the external magnet.11-27-2008
20100321819DISK DEVICE - In a positioning control system for a head of a magnetic disk device etc, a frequency of a disturbance oscillation having a specific oscillation component whose amplitude changes with a head position, is selected as a target frequency. Next, a resonance filter is so designed that it has a resonance characteristic at the target frequency and a variable gain device A having the gain changing with head position and a variable gain device B having inverse characteristics to the device A are connected to input and output terminals of the resonance filter, respectively. Input to the filter is made 0 during seek operation and an error signal is used as the input to the filter through the device A after the end of the seek operation. The variable gain devices A and B are controlled so that their product becomes 1.12-23-2010
20080253017APPARATUS FOR RECORDING OR RETRIEVING DATA ON MAGNETIC TAPE - A magnetic tape drive includes a magnetic head configured to read or write data on a magnetic tape, a transport unit configured to drive the magnetic tape past the magnetic head, a speed detector configured to obtain speed information related to a transport speed of the magnetic tape, a vibrator configured to vibrate the magnetic head, and a controller configured to carry out control over the vibrator based upon the speed information obtained by the speed detector. The controller determines whether the transport speed of the magnetic tape is not lower than a predetermined value, based upon the speed information, starts operation of the vibrator in response to a determination that the transport speed is lower than the predetermined value, and stops the operation of the vibrator in response to a determination that the transport speed is not lower than the predetermined value.10-16-2008
20080253016For Digital Information Adapted Memory Arrangement - The present invention refers to a digital information adapted memory arrangement, where said arrangement includes hard disc means and one or more writing and/or reading heads, said hard disc means (10-16-2008
20080204925Disk drive device and ramp used therefor - Embodiments of the present invention help to prevent data error occurrence in a hard disk drive by reducing the generation of dust caused by friction between a magnetic disk and a ramp. According to one embodiment, a hard disk drive comprises an enclosure, a motor for rotating a magnetic disk, an actuator for supporting a head slider for accessing the disk, and a ramp for loading/unloading the head slider disposed in the enclosure. The ramp comprises a tab slide formed of a resin material having a sliding characteristic to slide a tab at a tip end of the actuator at a specific velocity, and a slit on which a reinforcement made of a resin material with higher mechanical strength than the tab slide is formed.08-28-2008
20080204924Information recording device - Embodiments of the present invention help to compute controlling quantity to make the spacing between a floating head slider and a recording medium optimum without damaging the floating head slider and the recording medium by detecting the floating head slider's contact with the recording medium with high sensitivity. According to one embodiment, when the floating head slider is floating over the magnetic disk, a controller takes samples of a notable characteristic value (amplitude) from signals reproduced by a reproducing head, retains the variation of the sample amplitude as a reference signal, takes samples of amplitude from signals reproduced by the reproducing head while reducing the spacing between the floating head slider and the magnetic disk gradually, produces a signal which is the sample signal from which the reference signal is subtracted, detects the floating head slider's contact with the magnetic disk when the fluctuation of the signal so produced exceeds a reference value and, on the basis of a fly-height-control mechanism's controlling quantity at the time of the contact, computes the controlling quantity for making the spacing between the floating head slider and the magnetic disk optimum.08-28-2008
20080204922Methods and apparatus to monitor hard-disk drive head position - Methods and apparatus to monitor hard-disk drive head position are described. In one example, a hard-disk drive system includes a hard-disk drive platter, a hard-disk drive read head configured to read information from the hard-disk drive platter, and a hard-disk drive head position detector configured to a receive a signal via the hard-disk drive read head and to determine if oscillations in the distance between the hard-disk drive platter and the hard-disk drive read head indicate that contact between the hard-disk drive platter and the hard-disk drive read head is likely to occur08-28-2008
20100284108PROCESS FOR PRODUCING MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING AND REPRODUCING APPARATUS - A method for producing a magnetic recording medium having a magnetically partitioned magnetic recording pattern, comprising a step of forming a magnetic layer contains 0.5-6 atomic % of an oxide on a non-magnetic substrate; and a step of exposing regions of the magnetic layer, which magnetically partition the magnetic recording pattern, to a reactive plasma or reactive ion. The magnetic layer preferably has a non-granular structure, and in-plane orientated. After the step of exposure of the magnetic layer to a reactive plasma or reactive ion, a surface at least in said regions of magnetic layer having been exposed to the reactive plasma or reactive ion is preferably irradiated with an inert gas. Thus, a magnetic recording medium having a magnetic recording pattern with a high precision, and having high electromagnetic conversion characteristics and high recording density can be produced with an enhanced productivity.11-11-2010
20100027157MAGNETIC STORAGE APPARATUS, AND CONTROLLING METHOD THEREOF - According to an aspect of the embodiment, an MPU obtains, as a first gain value from a RDC, a gain value of a servo signal when data is read from a magnetic storage medium, and obtains, as a second gain value from the RDC, the gain value of the servo signal when data is written to the magnetic storage medium. The MPU controls supplied power for controlling flying height of the magnetic head when data is written to the magnetic storage medium based on a result of the comparing between the first gain value and the second gain value.02-04-2010
20110096434SYSTEMS HAVING WRITER WITH DEEPER WRAP AROUND SHIELD AND METHODS FOR MAKING THE SAME - A method according to one embodiment includes etching an underlayer positioned under a main pole for reducing a thickness thereof and creating an undercut under the main pole; adding a gap material along sides of the main pole and in the undercut; and forming a shield along at least a portion of the gap material. A magnetic head according to one embodiment includes a main pole; an underlayer positioned under the main pole and spaced therefrom, thereby defining an undercut therebetween; a first layer of gap material extending along sides of the main pole and in the undercut; a second layer of gap material extending continuously along the underlayer under the main pole; and a shield encircling the main pole, wherein the shield extends between the first and second layers of gap material in the undercut. Additional systems and methods are also presented.04-28-2011
20110080671HARD-DISK DRIVE INCLUDING FLY-HEIGHT-ADJUSTMENT HEATING ELEMENT AND POSITION-ADJUSTMENT HEATING ELEMENT AND METHOD OF CONTROLLING FLY HEIGHT - A hard-disk drive. The hard-disk drive includes a head-slider configured to fly in proximity with a recording surface of a magnetic-recording disk, and a fly-height variation compensator configured to generate a signal for compensating variation in fly height of a write element of the head-slider. The head-slider further includes the write element configured to write data to the magnetic-recording disk, a fly-height-adjustment heating element configured to displace the write element towards the magnetic-recording disk, and a position-adjustment heating element configured to displace the write element in at least a direction perpendicular to a flying direction. The fly-height variation compensator is further configured to add the signal for compensating variation in fly height to a control signal for output to the fly-height-adjustment heating element.04-07-2011
20110080670ON HEAD MICROELECTRONICS FOR WRITE SYNCHRONIZATION - The presently disclosed technology teaches integrating disc drive electronics into a transducer head. Decreased electrical transit times and data processing times can be achieved by placing the electronics on or within the transducer head because electrical connections may be made physically shorter than in conventional systems. The electronics may include one or more of a control system circuit, a write driver, and/or a data buffer. The control system circuit generates a modified clock signal that has a fixed relation to phase and frequency of a bit-detected reference signal that corresponds to positions of patterned bits on the disc. The write driver writes outgoing data bits received from an external connection to off-head electronics directly to the writer synchronized with the modified clock signal. The data buffer stores and converts digital data bits sent from the off-head electronics to an analog signal that is synchronized with the modified clock signal.04-07-2011
20080218895Systems and/or methods for controlling bias voltages between recording media and read/write heads in disk drive devices - Certain example embodiments relate to techniques for more precisely adjusting the spacing between a head and a disk in a disk drive device. A spindle motor of a disk drive device may be electrically isolated from at least the base plate by means of, for example, a nonconductive adhesive. Circuitry for monitoring and/or applying a voltage to the head and/or to the disk to control an amount of spacing between the head and the disk may be provided. In certain example embodiments, such circuitry may monitor the disk voltage and then apply an appropriate voltage bias to the head to control the spacing therebetween electrostatically. In certain other example embodiments, such circuitry may monitor the head voltage and then adjust the spindle voltage accordingly. In still other example embodiments, the disk voltage and the head voltage may be controlled and/or adjusted based on a known voltage differential so that a precise disk/head voltage potential is achieved.09-11-2008
20100182716DISK DRIVE HAVING MULITPLE DISK SURFACES ACCESSIBLE BY A READ/WRITE HEAD AND NONVOLATILE MEMORY FOR CONTINUOUS DATA TRANSFER - A magnetic recording hard disk drive (HDD) has at least one read/write head that accesses more than one disk surface. The HDD is able to transfer data to and from the host computer seamlessly without interruption during the time the head is being moved from one disk surface to another disk surface. Nonvolatile solid state memory is associated with pairs of disk surfaces. During the time of a head transfer from one disk surface in the pair to the other disk surface, data is read from or written to the associated nonvolatile memory. The data is first read from or written to one disk surface, then from or to the nonvolatile memory, and then, after completion of the head transfer, from or to the other disk surface, thereby allowing seamless uninterrupted transfer of data.07-22-2010
20100246052METHOD AND APPARATUS FOR ADAPTIVE GAIN BALANCING OF AT LEAST ONE OF TWO ROTATIONAL SENSORS IN A HARD DISK DRIVE - A hard disk drive and its circuit board and an integrated circuit are disclosed using two piezoelectric devices each having one terminal used to generate signal. The first signal goes to one input of a differential amplifier. The second signal goes to an amplifier whose gain is controlled to create an amplified second signal for the differential amplifier whose output and the first and second signals create a selected signal received by an A/D converter to create a sampled signal used to create a linear disturbance signal and/or a rotational compensation signal, which in turn are used to control the gain of the amplifier to minimize a PES envelope and/or a harmonic PES envelope either in calibration or normal operation of the hard disk drive.09-30-2010
20100165504METHOD OF PRODUCING MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING AND READING DEVICE - The present invention aims to provide a method of producing a magnetic recording medium which is a method of producing a magnetic recording medium having a magnetically-separated magnetic recording pattern, the method including: forming a magnetic layer on a non-magnetic substrate; then exposing a surface of the magnetic layer partially to reactive plasma, or a reactive ion generated in the plasma to amorphize the portion of the magnetic layer.07-01-2010
20100079899STORAGE APPARATUS AND METHOD OF ADJUSTING THE SAME - A storage apparatus includes a controller circuit controlling the operation of a head actuator for moving a head relative to a storage medium. The storage apparatus further includes an acceleration sensor detecting acceleration. A notch filter outputs the result of detection of the acceleration sensor to the controller circuit. A frequency setting circuit is configured to set the notch frequency of the notch filter in accordance with a resonance frequency of the acceleration sensor.04-01-2010
20100067140Disk-Drive Read/Write Head Retraction Velocity Control - One embodiment of the invention includes a voice coil motor (VCM) drive system. The system includes a VCM configured to move a read/write head across a magnetic disk in response to a current flow through the VCM. The system also includes a VCM output stage configured to direct the current through the VCM in one of a first direction corresponding to retraction of the read/write head and a second direction corresponding to extension of the read/write head in response to switching control signals. The system further includes a retract controller configured to control a retraction velocity of the read/write head by generating the switching control signals to provide the current in the first direction to increase the retraction velocity of the read/write head and to provide the current in the second direction to decrease the retraction velocity of the read/write head during a retraction mode of the VCM drive system.03-18-2010
20090323215HEAD POSITION CONTROL DEVICE, MAGNETIC DISK DEVICE, AND HEAD POSITION CONTROL METHOD - According to one embodiment, a head position control device includes a positioning controller, a sensor, and a storage module. The positioning controller outputs, to a head moving mechanism that moves a head in the radial direction of a magnetic disk, a control signal indicating a position to which the head is to be moved. The sensor detects the environmental temperature around the magnetic disk. The storage module stores expected temperatures each associated with a filter coefficient of a filter that attenuates specific frequency components of the control signal. The positioning controller creates a filter based on filter coefficients associated with two values of the expected temperatures close to the environmental temperature, and applies the filter to the control signal.12-31-2009
20090323216STORAGE APPARATUS AND STORAGE MEDIUM - A storage apparatus includes: a magnetic recording disk having discrete magnetic dots forming circular tracks coaxial with a rotation axis; a rotary actuator supporting a head slider facing the magnetic recording disk, the rotary actuator coupled to a pivot bearing shaft parallel to the rotation axis; and read and write elements separately-located at a gap distance on a given straight line. A distance between two circular tracks depends on the gap distance and the angle between one circular track of the two circular tracks and the given straight line.12-31-2009
20110188152SERVO PATTERNING AND WRITING COMPATIBLE WITH PLANARIZATION OF PATTERNED MAGNETIC DISKS - Embodiments herein illustrate patterned servo data that is used to facilitate subsequent servo writing to a magnetic disk while allowing the patterned disk to be planarized with a relatively simple planarization process. One disk drive system includes a magnetic disk that is patterned with magnetic lands and nonmagnetic grooves. The magnetic disk also includes bootstrap bands that may be configured at an inner diameter of the magnetic disk. The magnetic lands of the bootstrap bands have varying sizes and are patterned as servo data having a uniform polarity of magnetization. The bootstrap bands have a width that is sufficiently narrow to support an air bearing surface of a slider. The data tracks are circumferentially configured proximate to the bootstrap bands. The slider reads the patterned servo data to facilitate writing of additional servo data in the data tracks.08-04-2011
20100149680METHOD OF MANUFACTURING MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING REPRODUCING APPARATUS - The present invention provides a method of manufacturing a magnetic recording medium where at least a magnetic layer is formed on a non-magnetic substrate and a magnetically separated magnetic recording pattern is formed on the magnetic layer, including: a magnetic recording pattern forming process of forming magnetic recording areas that are constructed with convex portions and boundary areas that are constructed with concave portions between the magnetic recording area as the magnetic recording pattern on the magnetic layer; followed by a protective layer forming process of forming a protective carbon layer by using a high-frequency plasma chemical vapor deposition method and by applying a negative bias to the non-magnetic substrate to make the protective carbon layer on the magnetic recording area thinner than the protective carbon layer on the boundary area.06-17-2010
20110134564MAGNETIC HEADS HAVING A GRADED DOMAIN CONTROL FILM AND METHODS OF MANUFACTURE THEREOF - A magnetic head, according to one embodiment, includes a sensor film, a sensor cap film provided above the sensor film, a pair of shields including an upper magnetic shield and a lower magnetic shield which serve as electrodes that pass current in a film thickness direction of the sensor film, a track insulating film contacting both sides of the sensor film in the track width direction, a graded domain control film arranged on both sides in the track width direction of the sensor film adjacent the track insulating film, and an element height direction insulating film positioned on an opposite side of the sensor film relative to an air-bearing surface, wherein an edge position of the element height direction insulating film adjacent the sensor film on the air-bearing surface side is substantially the same as an edge position of the sensor cap film in the element height direction.06-09-2011
20110149430Magnetic Head Slider and Magnetic Disk Drive - A magnetic head slider is disclosed. The magnetic head slider includes a slider substrate and a laminated magnetic head element on the slider substrate. Additionally, the laminated magnetic head element includes a magnetoresistance effect element and a recording magnetic pole formed in a layer higher than the magnetoresistance effect element. A first thin-film resistor heater element is formed in a position further from an air bearing surface than the magnetoresistance effect element and the magnetic recording pole and a second film resistor heater element is formed in a layer lower than the first thin-film resistor heater element, and closer to the air bearing surface and the magnetoresistance effect element than the first heater element. A thin-film resistor sensor element is formed in a layer higher than the second thin-film heater element and closer to the air bearing surface than the second heater element.06-23-2011
20110149431Fall Detection Apparatus, Magnetic Disk Apparatus, and Portable Electronic Apparatus - A fall detection apparatus that detects values ax, ay, and az in accordance with acceleration in three mutually orthogonal axes (x, y, and z). Among these detected values, the fall detection apparatus determines values dxy and dzy which are the differences between the detected value for a reference axis, e.g., the y-axis, as well as the other detected values. A falling state signal is then generated when a preliminary determination state in which the determination values are within predetermined ranges continues for a predetermined time or longer.06-23-2011
20110149429FLOATING HEAD DEVICE FOR FLOATING A HEAD ON A MAGNETIC DISK AND METHODS OF MANUFACTURING A MAGNETIC DISK - In one embodiment, a method of manufacturing a magnetic disk includes rotating a magnetic disk, supporting a floating head on the rotating magnetic disk, the floating head having a slider body and an element unit formed on a trailing edge of the slider body, contacting a floating surface of the slider body with the magnetic disk, and protruding a portion of the floating head toward the magnetic disk due to application of power to a heater element within the element unit, wherein the element unit is positioned away from the magnetic disk. In another embodiment, a floating head includes a slider body comprising AlTiC, an element unit positioned on a trailing edge of the slider body, the element unit having an initial recess amount of at least about 4 nm, and a heater element positioned within an alumina protective film of the element unit.06-23-2011
20110149428SLIDER FLY-HEIGHT CONTROL IN A HARD DISK DRIVE - In fly-height control system, a slider comprises a spin torque oscillator that is configured for generating an RF carrier signal which is out-of-band of a frequency band of read data, write data, and control signals in a hard disk drive.06-23-2011
20100027156RECORDING MEDIUM DRIVING DEVICE - A magnetic disk device includes a VCM coil that controls the movement of a head for recording or reproducing information onto and from a rotating magnetic disk, and an airflow guiding unit that guides an airflow occurring by the rotation of the magnetic disk toward the VCM coil when the temperature of the VCM coil exceeds a limit temperature defined in advance.02-04-2010
20100027155MAGNETIC DISK APPARATUS AND METHOD FOR CONTROLLING PROJECTING AMOUNT OF MAGNETIC HEAD - A magnetic disk apparatus includes a magnetic disk, and a magnetic head facing the magnetic disk. The magnetic disk apparatus also includes a thermal deforming member and a thermal deformation controller. The thermal deforming member is provided in the magnetic head for thermally deforming the magnetic head to change the projecting amount of the magnetic head toward the magnetic disk. The thermal deformation controller controls the driving power supplied to the thermal deforming member, so that the falling characteristic of the driving power in transition from an on-state to an off-state is gentler in inclination than the rising characteristic of the driving power in transition from an off-state to an on-state.02-04-2010
20100027152SYSTEM, METHOD AND APPARATUS FOR DIRECT HEAD-DISK CLEARANCE MEASUREMENT BY SLIDER VIBRATION AND FLY HEIGHT CALIBRATION - A method models and calibrates the fly height of a slider above the disk for disk drives. The calibration scheme uses the Wallace spacing loss equation and laser doppler velocimetry to predict fly height and detect the actual fly height of the slider. The slider is vibrated at selected resonances, such as by capacitive coupling to the disk, and the fly height is gradually reduced. In one version, contact between the slider and disk may be detected using an arm electronics sensor. The amplitude of mean-to-peak, vibration detection is used as an indication of the actual fly height and to calibrate the modeled fly height.02-04-2010
20110216438READER-WRITER OFFSET CORRECTION FOR A DISK DRIVE - A servo wedge on a recording medium for a disk drive includes a gray-code field that stores a micro-jog correction factor for a data track. The micro-jog correction factor compensates for the effect of accumulated track pitch variations. In one embodiment, the radial wedge formed by gray-code fields for adjacent data tracks is a continuous radial wedge similar to the gray-code field used for encoding track numbers.09-08-2011
20110216439HEAD PARKING RAMP AND HARD DISK DRIVE HAVING THE SAME - A hard disk drive includes a head stack assembly having a read/write head to read data stored on a disk and/or to write data to the disk while flying over the disk. The read/write head includes an end tap that is disposed at a peripheral portion of the read/write head. A head parking ramp is arranged close to the disk and may support the read/write head while in the park position such that the end tap contacts the head parking ramp and is supported thereon. A heater is provided in the head parking ramp to heat the read/write head.09-08-2011
20090015961DISK DRIVE INSTALLED IN PORTABLE ELECTRONIC DEVICE, AND METHOD OF UNLOADING A HEAD WHEN THE ELECTRONIC DEVICE FALLS - According to one embodiment, a disk drive (HDD) is installed in a portable electronic device. The HDD includes an actuator which supports a head such that the head is radially movable over a disk. A constant speed controller incorporated in the HDD executes constant speed control for unloading the head onto a ramp at a constant speed in accordance with a fall detection signal output from a fall detector and indicating that fall of the device has been detected. In the constant speed control, the controller drives a voice coil motor as a drive source for the actuator to make the movement speed of the head identical to a first target speed. The first target speed is set higher than a second target speed set when the head is unloaded onto the ramp in a normal state.01-15-2009
20090147396SERVO WRITER WITH RETRACT CAPACITOR FOR GENERATING A VCM DRIVING CURRENT DURING A POWER FAILURE - A servo writer is disclosed for writing servo data onto a disk of a disk drive. The servo writer comprises a push-pin operable to contact an actuator arm of the disk drive, an actuator for actuating the push pin, and a retract capacitor. The retract capacitor is charged, and the actuator actuates the push-pin in order to position the head radially over the disk. If a power failure occurs while actuating the push-pin, a current is applied from the retract capacitor to a voice coil of the actuator arm in order to retract the actuator arm.06-11-2009
20100027154FLYING HEIGHT CONTROL DEVICE FOR MAGNETIC HEAD AND MAGNETIC DISK DEVICE - A floating amount of the magnetic head is controlled. The disk device has a temperature or humidity sensor and a controller. The controller monitors the detected temperature or humidity and retracts the magnetic head to an area where the circumferential speed is fastest, such as at the outermost side of the flying guarantee area of the magnetic disk, if the temperature or humidity is a predetermined value or more. The lubricant transferred from the magnetic disk to the magnetic head can be removed, and the increase of the flying height of the magnetic head can be suppressed.02-04-2010
20110051282MAGNETIC RECORDING MEDIUM, MAGNETIC RECORDING AND REPRODUCING APPARATUS, AND METHOD FOR MANUFACTURING MAGNETIC RECORDING MEDIUM - There is provided a magnetic recording medium which can be manufactured at a high production efficiency, and in which a protruding section constituted of a magnetic layer can be separated by a recessed separating region, and stability for the floating properties of the magnetic head is excellent,03-03-2011
20110051281MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING/REPRODUCING APPARATUS - A magnetic recording medium having a magnetic pattern magnetically partitioning a magnetic layer, formed on a non-magnetic substrate, wherein the magnetic pattern is comprised of magnetic regions and non-magnetic regions surrounding each of the magnetic regions, the non-magnetic regions form depressions, the magnetic pattern comprises data areas and servo information areas, and the difference between the areal ratio of the depressions in the data areas and the areal ratio thereof in the servo information areas is within ±10%. The magnetic areas preferably comprise a magnetic layer having a granular structure comprised of magnetic grains each surrounded by an oxide, or a two-layer structure comprising the granular structure and a non-granular structure formed on the granular structure. The magnetic recording medium exhibits stable head-floating characteristics, and thus, the largest floating height can be reduced, and a high recording density can be obtained.03-03-2011
20130170068MAGNETIC DOMAIN CONTROL FOR AN EMBEDDED CONTACT SENSOR FOR A MAGNETIC RECORDING HEAD - A head for magnetic data recording that includes an embedded contact sensor. The embedded contact sensor detects head disk contact by detecting changes in temperature as a result of contact between the head and the disk. The embedded contact sensor includes a thermoresistive layer and a structure for pinning the magnetic domains of the thermoresistive layer. This pinning of the magnetic domains prevents the thermoresistive layer from changing resistance in response to magnetic fields (rather than temperature) so as to avoid unwanted signal noise as a result of a magnetic signal from the magnetic media.07-04-2013
20120307398THERMALLY ASSISTED MAGNETIC RECORDING MEDIUM AND MAGNETIC STORAGE DEVICE - Disclosed is a thermally assisted magnetic recording medium comprising a substrate, a plurality of underlayers formed on the substrate, and a magnetic layer which is formed on the underlayers and predominantly comprised of an alloy having a L112-06-2012
20120307396MAGNETIC HEAD HAVING POLYCRYSTALLINE COATING - A magnetic head according to one embodiment includes a substrate; an array of transducers formed on the substrate, wherein the transducers and substrate form portions of a magnetic media facing surface; and an at least partially polycrystalline dielectric layer on the media facing surface, wherein the at least partially polycrystalline dielectric layer is on a magnetic film of at least one of the transducers in the array. A method for forming an at least partially polycrystalline dielectric layer on a media facing surface of a magnetic head according to one embodiment includes forming an at least partially polycrystalline dielectric layer on an array of transducers of a magnetic head, wherein an oxide layer is formed above at least some of the magnetic layers before and/or during the forming of the at least partially polycrystalline dielectric layer.12-06-2012
20120099221Head stack assembly and hard disk drive with the same - An HSA comprises at least an HGA, a controlling circuit for controlling the HGA, and an actuator coil assembly comprising at least one top surface for mounting the HGA and a side surface for mounting the controlling circuit. The HGA has a first connection region parallel to the top surface, the first connection region has multiple first terminal pads formed thereon; the controlling circuit has a second connection region with multiple second terminal pads formed thereon, the second terminal pads are arranged in at least one row which is parallel to the top surface and the side surface, the first terminal pads are bonding to the corresponding second terminal pads to implement an electrical connection. The HSA has a compact structure as so to save space, and the connection way of the HGA and the controlling circuit is simple and solid.04-26-2012
20120099220PERPENDICULAR MAGNETIC RECORDING MEDIUM (PMRM) AND SYSTEMS THEREOF - In one embodiment, a perpendicular magnetic recording medium includes a crystalline seed layer having a pseudo-hcp structure with stacking faults formed above a soft magnetic underlayer, a first interlayer comprising Ru and one of W, Ta, Mo, and Nb formed above the crystalline seed layer, a second interlayer formed above the first interlayer, and a magnetic recording layer formed above the second interlayer. The first interlayer has a W concentration between about 32 at % and 50 at %, Mo in a concentration between about 36 at % and 52 at %, Ta in a concentration between about 20 at % and 30 at %, or Nb in a concentration between about 7 at % and 30 at %. In another embodiment, a system includes a recording medium as described above, a magnetic head for reading from and/or writing to the medium, a head slider for supporting the head, and a control unit coupled to the head.04-26-2012
20120038998Systems and Methods for Phase Offset Based Spectral Aliasing Compensation - Various embodiments of the present invention provide systems and methods for phase offset based spectral aliasing compensation. For example, a circuit for spectral aliasing reduction is disclosed that includes a phase shift circuit operable to phase shift an analog input signal and to provide a phase shifted analog signal; a first analog to digital converter circuit operable to provide a first series of digital samples corresponding to the analog input signal at a sampling frequency; a second analog to digital converter circuit operable to provide a second series of digital samples corresponding to the phase shifted analog signal at the sampling frequency; and an averaging circuit operable to average the first series of digital samples with the second series of digital samples to yield an average output.02-16-2012
20110063751METHOD AND APPARATUS FOR POSITIONING A MAGNETIC-RECORDING HEAD - A method for positioning a magnetic-recording head. The method includes correcting amplitude of each burst signal of a plurality of burst signals read out with the magnetic-recording head from each respective burst pattern of a plurality of burst patterns. In addition, the method includes computing a deviation of the magnetic-recording head from a track based on corrected amplitudes of the plurality of burst signals. Moreover, the method includes positioning the magnetic-recording bead on the track based on the deviation of the magnetic-recording head.03-17-2011
20110317308MAGNETIC RECORDING APPARATUS - According to one embodiment, a magnetic recording apparatus includes a magnetic recording medium for perpendicular magnetic recording system, a magnetic head including a read head to read data from the magnetic recording medium, and an actuator to actuate the magnetic head on the magnetic recording medium. The magnetic recording medium includes a first magnetic pattern recorded in a servo area by applying a magnetic field horizontally to a disk surface, and the first magnetic pattern corresponding to positioning data used for positioning the magnetic head. The magnetic recording medium further includes a second magnetic pattern recorded in the servo area by applying a magnetic field perpendicularly to the disk surface, and the second magnetic pattern corresponding to position correction data used for correcting the positioning data. The position correction data is derived from modulated original position correction data. The original position correction data is created for correcting the positioning data.12-29-2011
20110317307Motor and recording disc driving device - There are provided a motor and a recording disc driving device, which may minimize a frictional force between a shaft and a bearing assembly to enable a rotor to be readily rotated at the time of initial movement of the rotor. The motor may include: a bearing assembly including a shaft rotatably fastened to the bearing assembly; a base fastened to a lower end portion of the bearing assembly; a stator fastened to the base and including a winding coil; and a rotor case fastened to an upper end portion of the shaft, and including a magnet fastened to the rotor case to be positioned to face the winding coil, wherein the magnet is fastened to the rotor case in such a manner as to be protruded towards a lower portion of the rotor case so that a magnetic force due to an eddy current generated in the base is increased.12-29-2011
20120044595PERPENDICULAR MAGNETIC RECORDING MEDIUM (PMRM) AND MAGNETIC STORAGE SYSTEMS USING THE SAME - In one embodiment, a perpendicular magnetic recording medium (PMRM) includes a first interlayer comprising Ru or a Ru alloy, a second interlayer above the first interlayer comprising Ru or a Ru alloy, and a third interlayer formed between the first interlayer and the second interlayer that reduces an average cluster size of the second interlayer. In another embodiment, a PMRM includes a first interlayer comprising Ru or a Ru alloy, a second interlayer above the first interlayer comprising Ru or a Ru alloy, and a third interlayer formed between the first interlayer and the second interlayer that reduces an average cluster size of the second interlayer. The third interlayer has a thickness of between about 1.0 nm and about 3.0 nm and has a structure selected from a group consisting of: BCC, B2, C11b, L21, and D03. Other PMRMs and methods of fabrication are presented as well.02-23-2012
20100177429Readback Signal-Based Head-Disc Contact Detection Using AM/FM Demodulation - A method includes: producing a readback signal using a recording head positioned adjacent to a recording medium, amplitude demodulating the readback signal to produce an amplitude demodulated signal, frequency demodulating the readback signal to produce a frequency demodulated signal, and using the amplitude demodulated signal and the frequency demodulated signal to determine contact of the recording head with the recording medium. An apparatus that can be used to implement the method is also provided.07-15-2010
20120206833Method of Positioning a Transducer with a Magnetically Preloaded Linear Guide - A transducer positioning apparatus is provided that supports a read/write head on a data storage machine and biases the head against rotation. The transducer positioning apparatus may comprise a base that includes a linear drive motor and a support frame to which the read/write head is secured. The support frame is reciprocally driven by the linear drive motor relative to the base. A magnetic coupling is provided between the base and the support frame that resists movement of the frame other than the reciprocal movement of the support frame relative to the base. A method is also disclosed for magnetically biasing a movable head of a transducer against rotation.08-16-2012
20120008232CONTROLLING POSITIONS OF STORAGE MEDIA HEADS - Controlling positions of storage media heads is disclosed. An example storage media head position controller includes a position error filter to filter a media head position error based on a target position for a storage media head relative to a storage medium and a present media head position to generate a position signal, and a media speed monitor to modify an integration factor in the position error filter based on a media speed to adjust a phase margin of the position control loop.01-12-2012
20120008233Extended Cavity VCSEL Mounted to Substrate with Electrical and Thermal Contact to Substrate and Optical Power Directed Toward Substrate - A system according to one embodiment includes a slider adapted for use in a hard disk drive; and a laser coupled to a slider, wherein electrical contacts of the laser are positioned towards or face the slider, wherein light from the laser is emitted towards the slider, wherein the slider acts as a heat sink for the laser.01-12-2012
20100157464Systems and Methods for Adaptive MRA Compensation - Various embodiments of the present invention provide systems and methods for reducing head distortion. For example, various embodiments of the present invention provide storage devices that include a storage medium, a read/write head assembly, and an adaptive distortion modification circuit. The storage medium includes information that may be sensed by the read/write head assembly that is disposed in relation to the storage medium. The adaptive distortion modification circuit receives the information sensed by the read/write head assembly and adaptively estimates and implements a distortion compensation factor in the analog domain. In some instances of the aforementioned embodiments, the read/write head assembly includes a magneto resistive head. In such instances, the distortion compensation factor is designed to compensate for non-linear distortion introduced by the magneto resistive head.06-24-2010
20120307397MAGNETIC HEAD HAVING SEPARATE PROTECTION FOR READ TRANSDUCERS AND WRITE TRANSDUCERS - A magnetic head according to one embodiment includes outer modules each having a media bearing surface and an array of transducers selected from a group consisting of data read transducers and write transducers; and at least one inner module positioned between the outer modules, the inner module having a media bearing surface and an array of transducers selected from a group consisting of data read transducers and write transducers, wherein a configuration of at least one protection feature for the transducers on the outer modules is different than a configuration of at least one protection feature for the transducers on the inner modules.12-06-2012
20110085261MAGNETORESISTIVE MAGNETIC HEAD HAVING A NON-MAGNETIC PART ON A MEDIUM FACING SURFACE SIDE OF THE SENSOR - According to one embodiment, a magnetic head includes an upper magnetic shield, a lower magnetic shield,a magnetoresistive element having a magnetization-free layer formed therein formed between the shields, an upper magnetic shield restricting part formed on a medium facing surface side, a lower magnetic shield restricting part formed on the medium facing surface side, and a non-magnetic part formed between the upper and lower magnetic shield restricting parts on the medium facing surface side such that the magnetoresistive element is not exposed at the medium facing surface. The non-magnetic part is positioned such that a distance between the upper and lower magnetic shield restricting parts in a direction perpendicular to a plane of deposition is smaller than a distance between the upper and lower magnetic shields in the direction perpendicular to the plane of deposition near the medium facing surface. Other systems and heads are disclosed as well.04-14-2011
20110085260DISK DRIVE AND SERVO CONTROL METHOD FOR THE DISK DRIVE THAT IS RESPONSIVE TO VIBRATION - A disk drive. The disk drive includes an acceleration sensor, a servo controller, a detection determiner, and a handling processor. The acceleration sensor has an associated resonant frequency. The servo controller is configured to perform servo control for head positioning using frequency components that are obtained by cutting off frequency components including the resonant frequency from output of the acceleration sensor. The detection determiner is configured to detect a frequency band including the resonant frequency from the output of the acceleration sensor to determine whether a magnitude of a voltage amplitude of the frequency band is outside of a specified range. The handling processor is configured to execute a corresponding handling operation if the detection determiner determines that the magnitude of the voltage amplitude of the frequency band is outside of the specified range.04-14-2011
20120206832TAPE HEAD ACTUATOR - An assembly according to one embodiment includes a first module and a second module each having multiple transducers, wherein the first module is movable relative to the second module; a tape dimensional stability compensation mechanism for tilting the modules to control a transducer pitch presented to a tape; and an actuator adapted to exert a force on both modules for causing the relative movement of the first module with respect to the second module for aligning the transducers of the first module with the transducers of the second module in a direction of tape travel thereacross.08-16-2012
20120063026BASEPLATE WITH RECESSED REGION IN A HARD-DISK DRIVE (HDD) - Approaches for a hard-disk drive (HDD) baseplate comprising a recessed region that provides additional clearance for a disk. The protective enclosure of the HDD comprises a baseplate. The surface of the baseplate, which opposes a magnetic-recording disk, comprises a recessed region near the outer diameter (OD) of the magnetic-recording disk. The recessed region prevents the disk from being damaged through inadvertent physical contact with the baseplate, which may arise when the HDD receives a mechanical shock. The recessed region may be designed to minimize the damage to the disk if physical contact between the disk and the baseplate does occur. The recessed region may have a variety of shapes, such as a circular indentation or one or more non-contiguous regions in the baseplate where physical contact between the disk and the baseplate is deemed likely to occur.03-15-2012
20120300340INFORMATION PROCESSING APPARATUS, PROTECTION METHOD AND MEDIUM STORING PROTECTION PROGRAM - Disclosed is an information processing apparatus comprising a housing (11-29-2012
20120300338LOW FRICTION TAPE HEAD AND SYSTEM IMPLEMENTING SAME - A magnetic head according to one embodiment includes outer modules each having a tape bearing surface and an array of transducers selected from a group consisting of readers and writers; and an inner module positioned between the outer modules, the inner module having a tape bearing surface and an array of transducers selected from a group consisting of readers and writers, wherein portions of edges of the tape bearing surface of the inner module are non-skiving in regions not aligned with the array of transducers in a direction of media travel thereacross, wherein an outer edge of the tape bearing surface of each of the outer modules are adapted for skiving air from the magnetic medium when the magnetic medium travels in a direction from the respective outer module towards the inner module.11-29-2012
20120154948PERPENDICULAR MAGNETIC RECORDING MEDIA HAVING LOW MEDIUM NOISE AND SYSTEMS USING THE SAME - In one embodiment, a perpendicular magnetic recording medium includes a substrate, a soft-magnetic underlayer above the substrate, a seed layer above the soft-magnetic underlayer, a first intermediate layer above the seed layer, a second intermediate layer above the first intermediate layer, a recording layer above the second intermediate layer, and a protective layer above the recording layer. The second intermediate layer includes an Ru alloy having an element selected from a group consisting of: Ti in a range from about 20 at. % to about 50 at. %, Nb in a range from about 20 at. % to about 50 at. %, Al in a range from about 20 at. % to about 40 at. %, Ta in a range from about 30 at. % to about 50 at. %, and Si in a range about 20 at. % to about 40 at. %. Other magnetic media and systems using this media are described according to more embodiments.06-21-2012
20100277827Correcting Errors in Position of an HDD Write-Head - A hard-disk drive (HDD) with a current adjustment component is provided. The current adjustment component changes an amount of current to a magnetic-recording head of the HDD to cause a change in the strength of a magnetic write field produced by the magnetic-recording head in response to a determination that a present position of the magnetic-head head is not in a desired position. To illustrate, in response to a determination that the present position of the magnetic-recording head is further away from an edge of a current track being written than a desired position of the magnetic-recording head, the current adjustment component increases the current to the magnetic-recording head to cause an increase in the strength of the magnetic write field. The change in the strength of the magnetic write field causes data, written by the magnetic-recording head, to be located at a desired location on the magnetic-recording disk.11-04-2010
20090135514METHOD AND APPARATUS FOR REDUCING COUPLED HARD DISK DRIVE VIBRATION - Some embodiments of the present invention provide a system that includes a first hard disk drive (HDD) and a second HDD. Within this system, the first HDD is coupled to the second HDD in a non-parallel configuration, which reduces rotational vibration transmitted between the first HDD and the second HDD.05-28-2009
20090135517Magnetic disk unit and manufacturing method thereof - Embodiments of the present invention relate to a method for manufacturing a magnetic disk unit, the method including a step of writing servo data into the magnetic disk while introducing a low-density gas having a lower density than air into the enclosure. In one embodiment, the magnetic disk unit is comprised of a magnetic disk, a magnetic head, and a voice coil motor which are accommodated in the hermetically sealed enclosure. The enclosure has a gas inlet and a gas outlet, which are provided respectively with filters attached thereto.05-28-2009
20090135516Disk drive device and servo control method thereof - Embodiments of the present invention help to perform appropriate servo control in response to detected vibration in a disk drive device having a vibration sensor. In an embodiment of the present invention, an HDD switches a correction servo mode to perform vibration correction in head positioning and a normal servo mode not to perform the vibration correction. The HDD performs servo positioning in either one of the serve modes and determines servo positioning accuracy in the servo mode from the measured positional error signal. The HDD obtains data indicating the servo positioning accuracy in the other servo mode from a table. The HDD compares the accuracy in the two servo modes and selects the servo mode with higher accuracy. The table contains previous measurements on servo positioning accuracy in the servo modes.05-28-2009
20100177431INFORMATION STORAGE APPARATUS, ADJUSTMENT APPARATUS THEREOF, AND METHOD FOR FORMING SERVO PATTERN - According to one embodiment, an information storage apparatus comprises a storage medium on which a first servo pattern having absolute position information and a second servo pattern having relative position information are recorded, a head configured to record and reproduce information on and from the storage medium, a recording signal generator configured to generate a control signal for making the head record a third servo pattern having absolute position information on the storage medium while positioning the head by using the first and the second servo patterns, and a data storage unit configured to store recording data for recording the third servo pattern on the storage medium.07-15-2010
20110090589MAGNETIC HEADS HAVING MAGNETIC FILMS THAT ARE MORE RECESSED THAN INSULATING FILMS, AND SYSTEMS HAVING SUCH HEADS - A structure according to one embodiment includes a substrate having a media facing side; and a thin film stack formed on the substrate, the thin film stack including magnetic films and insulating films, wherein the thin film stack is recessed from a plane extending along the media facing side of the substrate, wherein the magnetic films are recessed more than the insulating films, wherein the magnetic films each have a substantially flat media facing surface, wherein the insulating films each have a substantially flat media facing surface.04-21-2011
20110102936PERPENDICULAR MAGNETIC RECORDING HEAD AND METHOD FOR PRODUCING THE SAME - According to one embodiment, a perpendicular magnetic recording head includes a main pole, wherein a thickness in a down-track direction of the main pole increases moving away from an air bearing surface of the magnetic pole, and wherein a center position in a thickness direction of a portion of the main pole which is exposed at the air bearing surface (the ABS portion) is positioned toward a trailing side of the main pole with respect to a center position in a thickness direction of a portion of the magnetic pole having a greatest cross-sectional area and which is set back from the air bearing surface (the set-back portion). Further embodiments of this magnetic recording head, along with systems thereof and methods of producing magnetic recording heads are also described, according to more embodiments.05-05-2011
20110102933DISK DRIVE AND METHOD FOR MEASURING CLEARANCE CHANGE IN THE DISK DRIVE - A method for measuring a change of a clearance between a head and a disk. The method includes reading a preliminarily written data string for clearance measurement on a disk to obtain a first measured value corresponding to a clearance, and writing a new data string for deterioration check onto the disk and reading the data string for deterioration check to obtain a second measured value corresponding to the clearance. The method also includes determining a deterioration of the data string for clearance measurement from a difference between the first measured value and the second measured value, measuring a clearance change using the data string for clearance measurement by a normal operation if the determination is that the data string for clearance measurement has not deteriorated, and measuring a clearance change by an operation different operation if the determination is that the data string for clearance measurement has deteriorated.05-05-2011
20110102935HEAD-STACK ASSEMBLY INCLUDING HEAT-DISSIPATION AND IMPEDANCE-MATCHING STRUCTURE AND HARD-DISK DRIVE USING THE HEAD-STACK ASSEMBLY - A head-stack assembly. The head-stack assembly includes: a magnetic-recording head; a lead-suspension supporting the magnetic-recording head on an actuator arm; a metal plate coupled with the actuator arm; a resin layer disposed on the metal plate; a flexible-printed-circuit board disposed on the resin layer, and substantially perpendicularly connected to the lead-suspension; a arm-electronics module disposed on the flexible-printed-circuit board configured to shape a write-signal current waveform of a write signal to said magnetic-recording head; transmission lines disposed on the flexible-printed-circuit board configured to transmit the write signal to, and a read-back signal from, the lead-suspension; and, a single intermediate conductor layer that is disposed between the resin layer and the flexible-printed-circuit board, and having a planar shape substantially facing a bottom of the arm-electronics module and a bottom of the transmission lines.05-05-2011
20110102934CANCELLATION OF TIME-VARYING PERIODIC DISTURBANCES IN SERVO CONTROL SYSTEMS - Various embodiments for addressing time-varying periodic disturbances in a servo control system are provided. Each of a plurality of coefficients is updated based on an estimation of at least one disturbance frequency. The updated plurality of coefficients is provided to at least one peak filter modifying an input signal of the servo control system. The peak filter is operable in view of the updated plurality of coefficients to cancel at least one of the time-varying periodic disturbances.05-05-2011
20100091400MAGNETIC DISK APPARATUS AND SLIDER FOR MAGNETIC RECORDING - According to one embodiment, a magnetic disk apparatus includes a patterned disk, a slider, two read heads, a write head, and a drive circuit. The patterned disk has a magnetic recording surface on which bit patterns are arranged concentrically. The slider is located near the magnetic recording surface, and moves relatively to the magnetic recording surface. The read heads are arranged along a medium running direction at an end of the slider, and read magnetic data from the magnetic recording surface. The write head is located between the read heads, and records magnetic data to the bit patterns. The drive circuit drives the write head at a timing based on a period from when one of the read heads located upstream in the medium running direction reads magnetic data until the other located downstream reads the magnetic data at the same position on the magnetic recording surface.04-15-2010
20120120522Head Transducer with Multiple Resistance Temperature Sensors for Head-Medium Spacing and Contact Detection - A head transducer, configured to interact with a magnetic recording medium, includes a first sensor having a temperature coefficient of resistance (TCR) and configured to produce a first sensor signal, and a second sensor having a TCR and configured to produce a second sensor signal. One of the first and second sensors is situated at or near a close point of the head transducer in relation to the magnetic recording medium, and the other of the first and second sensors spaced away from the close point. Circuitry is configured to combine the first and second sensor signals and produce a combined sensor signal indicative of one or both of a change in head-medium spacing and head-medium contact. Each of the sensors may have a TCR with the same sign (positive or negative) or each sensor may have a TCR with a different sign.05-17-2012
20100290152METHOD OF MANUFACTURING MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING AND REPRODUCING APPARATUS - There is provided a method of manufacturing a magnetic recording medium where a magnetic layer is formed on a substrate, followed by formation of a magnetic pattern, which is a method producing few defective products with low production cost, the method of manufacturing a magnetic recording medium having magnetic recording patterns which are magnetically separated, including, in the following order: a step of forming a magnetic layer on a substrate which has an opening in the centre; a step of applying a resin film to the magnetic layer; a step of pressing against the substrate a film-type mold on which an uneven pattern has been formed; a step of transferring the uneven pattern of the mold onto the resin film; a step of separating the mold from the substrate; and a step of forming magnetic recording patterns on the magnetic layer using the uneven pattern which has been transferred.11-18-2010
20100246054Magnetic Recording And Reading Device - A magnetic recording and reading device includes a perpendicular magnetic recording medium, a perpendicular magnetic head having a recording head width having a heat-generating portion and a reading head, a fine adjustment portion, and a R/W-IC. The perpendicular magnetic head is configured to perform magnetic recording on the recording medium while locally heating the recording medium so as to enable a change of the coercive force of the recording medium during the recording after correcting of the position of the perpendicular magnetic head by the fine adjustment portion is completed, and to perform reading of the magnetic recording information with the aid of the reading head after correcting of the position of the perpendicular magnetic head by the fine adjustment portion is completed.09-30-2010
20100246053STORAGE DEVICE AND RAMP MECHANISM - According to one embodiment, a storage device has a head configured to read or write data with respect to a storage medium above the storage medium; a head suspension configured to support the head; a lift tab extending from an end on a head side of the head suspension; and a ramp mechanism configured to hold the lift tab at a retracted position spaced apart from the recording medium. The ramp mechanism has: a rotating shaft; and a disk rotatably supported by the rotating shaft and configured to rotate in a retracting direction by coming into contact with the lift tab that is retracting with the head from above the recording medium, and to guide and retract the lift tab to the retracted position.09-30-2010
20120127603MAGNETIC TUNNEL JUNCTION HAVING A MAGNETIC INSERTION LAYER AND METHODS OF PRODUCING THE SAME - According to one embodiment, a magnetic head includes a barrier layer having a crystalline structure, a first magnetic layer above the barrier layer, a magnetic insertion layer above the first magnetic layer, and a second magnetic layer above the magnetic insertion layer, the second magnetic layer having a textured face-centered cubic (fcc) structure. The first magnetic layer comprises a high spin polarization magnetic material having a crystalline structure and a characteristic of crystallization being more similar to the crystalline structure of the barrier layer than a crystalline structure of the second magnetic layer and the magnetic insertion layer comprises a magnetic material having a crystalline structure and a characteristic of crystallization being more similar to the crystalline structure of the second magnetic layer than the crystalline structure of the barrier layer. Additional magnetic head structures and methods of producing magnetic heads are described according to more embodiments.05-24-2012
20120127602NOVEL THERMAL ACTUATOR DESIGN FOR THERMAL FLYING HEIGHT CONTROL SLIDER - This invention relates to a slider that includes a thermal actuator for controlling the flying height of the slider over a disk in a HDD. The thermal actuator comprises a thermal insulator, a thermal heater and a thermal conductor. The thermal heater is proximate a bottom surface of a slider body on one side of a read/write element. The thermal conductor has a higher thermal coefficient of thermal expansion than a remainder of the slider body and is formed between the first thermal heater and the one side of the read/write element. The first thermal insulator is proximate the bottom surface of the slider body and adjacent to the first thermal heater on an opposing side of the first thermal heater.05-24-2012
20120162812IMPACT ENERGY DISPERSING CRASH STOP FOR A HARD DISK DRIVE - A hard disk drive including a crash stop is disclosed. The crash stop includes a shaft and a resilient member covering a portion of the shaft. In addition, the resilient member includes a right side protrusion and a left side protrusion. The right and left side protrusions are configured to disperse energy from an impact between a head stack assembly and the crash stop.06-28-2012
20120162814INFORMATION RECORDING DEVICE AND INFORMATION RECORDING METHOD - An information recording device includes a magnetic disk, a recording control module, a detection module, and a rewrite control module. Tracks are defined on the magnetic disk, each track includes servo regions including position information and data regions. The recording control module performs a control so that information is recorded on a first track by a recording method where recording is performed with adjacent tracks overlapped with each other. The detection module detects, based on position information acquired from a first servo region, whether a shift recording is performed so as to be shifted from a reference in a radial direction on the first track. The rewrite control module performs, when the shift recording is detected, a control so that information is re-recorded in a data region between a first servo region and a second servo region that precedes the first servo region.06-28-2012
20120162813MAGNETIC DISK DRIVE AND METHOD FOR CONTROLLING MICROACTUATOR IN MAGNETIC DISK DRIVE - According to one embodiment, a magnetic disk drive includes a disk, a first microactuator, a second microactuator and a servo controller. The disk comprises a first surface and a second surface. The first and second microactuators allow first and second heads associated with the first and second surfaces to make micromotion based on first and second operation amounts, respectively. The servo controller provides a third operation amount to the first microactuator as the first operation amount and provides an operation amount obtained by inverting a polarity of a frequency component with a particular frequency contained in the third operation amount, to the second microactuator as the second operation amount, if the third operation amount is generated as an operation amount to be provided to the first microactuator in a particular mode in which the first surface is used as a tracking surface.06-28-2012
20120162810MAGNETIC HEAD HAVING A PLANAR HALL EFFECT READ SENSOR - In one embodiment a magnetic head includes a sensor thin film adapted for producing a planar Hall voltage, the sensor thin film having a thickness along a down-track direction that is greater than a thickness along a cross-track direction. The down-track direction is in a direction of travel of a magnetic medium relative to the sensor thin film, and the cross-track direction is perpendicular to the down-track direction. In another embodiment, at least one magnetic head as described above is included in a magnetic data storage system, which includes a magnetic medium, a drive mechanism for passing the magnetic medium over the at least one magnetic head, and a controller electrically coupled to the at least one magnetic head for controlling operation of the at least one magnetic head. Other heads and systems are described according to various other embodiments.06-28-2012
20120162811MAGNETIC RECORDING HEAD HAVING A NON-CONFORMAL SIDE GAP AND METHODS OF PRODUCTION THEREOF - In one embodiment, a magnetic head includes a main pole having a leading side and a trailing side relative to a downtrack direction, a side gap layer positioned adjacent to the main pole in a crosstrack direction, and a side shield layer positioned adjacent the side gap layer in a crosstrack direction. The downtrack direction is in a direction of medium travel relative to the main pole, the crosstrack direction is perpendicular to the downtrack direction, the side gap layer is characterized by having a groove therein in the downtrack direction having the main pole positioned therein, the side shield is characterized by having a groove formed therein in the downtrack direction having the side gap layer positioned therein, the side gap is non-conformal in shape, and a position of the side shield relative to a position of the main pole is characterized as being self-aligned.06-28-2012
20090251819HARD DISK DRIVE AND METHOD OF SETTING A WRITE-VERIFY TEMPERATURE THEREOF - A method of setting a write-verify temperature of a hard disk drive having at least one disk mapped into a plurality of zones and at least one head. The method can include measuring at least one parameter related to performance of the hard disk drive for each head and each zone, and setting a critical temperature to activate a write-verify function of each head and each zone based on the at least one parameter measured for each head and each zone.10-08-2009
20100208385STORAGE DEVICE WITH READ-AHEAD FUNCTION - According to one embodiment, a storage device includes a link information creation module and a read-ahead process module. The link information creation module creates link information for associating storage regions on a storage medium, which store a plurality of data included in a single file, in an order according to continuity of the plurality of data. The read-ahead process module performs a read-ahead of data stored in a storage region on the basis of the link information, the storage region being associated with a storage region of the storage medium which is designated by the data read request.08-19-2010
20100208384Multi-head array hard drive - A multiple head array hard drive comprises a multiple fixed head array. The multiple fixed head array has multiple rows of read write heads. The read write heads of a row are fixed relative to each other on the multiple fixed head array. The heads of the multiple fixed head array are arranged in a staggered pattern. The staggered pattern can be a zigzag pattern or a diagonal pattern. The disk has data encoded on the disk. The multiple fixed head array is positioned to read data over a surface of the disk. The disc rotates relative to the multiple fixed head array.08-19-2010
20100208383DATA STORAGE APPARATUS AND METHOD - A data storage apparatus and method. The apparatus comprises a mounting structure, a motor mechanically attached to mounting structure, and a data storage platter mechanically attached to the motor. The apparatus additionally comprises a single actuator arm comprising a first and second read/write data head or multiple radial movement mechanisms each comprising a read/write data head. The single actuator arm is configured to move axially along an arc and across a top surface of the data storage platter such that the first read/write data head has access to a first section and a second section of the data storage platter and the second read/write data head only has access to the second section of data storage platter. Each radial movement mechanism moves a different read/write data head radially all along a radius of the data storage platter and over and across different sections of the data storage platter.08-19-2010
20120212854SHUNT FOR MAGNETORESISTIVE TRANSDUCER HEADS FOR ELECTROSTATIC DISCHARGE PROTECTION - A magnetoresistive transducer head assembly includes a reader element, a writer element and a high impedance shunt electrically connecting the reader element and the writer element. The high impedance shunt provides a high impedance conductive path for maintaining electrostatic charge equipotential between the reader element and the writer element.08-23-2012
20120212853Method and Apparatus to Position a Head Module Comprising Servo Elements and Plurality of Data Elements - A method to position a head module, where the head module comprises at least one servo element and a plurality of data elements, where the servo element and each of the plurality of data elements can detect a servo signal, wherein the method includes moving a sequential information storage medium having a servo band encoded therein across the head module and detecting the servo band using the at least one servo element or any one of the plurality of data elements.08-23-2012
20120314321POSITION DEMODULATION APPARATUS AND POSITION DEMODULATION METHOD - According to one embodiment, a position demodulation method includes demodulating a first demodulation signal and a second demodulation signal having a phase difference of 90 degrees to the first demodulation signal based on a read-out signal obtained by reading out a servo pattern recorded on a medium by the head for positioning of a head with respect to the medium; correcting the first and second demodulation signals in which, when a trace of a Lissajous figure is drawn representing the first and second demodulation signals as values on coordinate axes different from each other on a plane, a ratio of respective lengths between intersections of the trace intersecting with two axes orthogonal at an origin of the plane is kept constant; and demodulating a positional signal for determining a position of the head based on the first and second demodulation signals after being corrected at the correcting.12-13-2012
20090059418MAGNETIC HEAD AND DISK DRIVE WITH HIGH-FREQUENCY ASSISTED WRITING - According to one embodiment, a magnetic head having a head slider which holds a magnetic head unit including a heat-generating element for controlling the flying-height and a high-frequency oscillator for performing high-frequency assisted writing, and on which terminals connected to the magnetic head elements are used in the smallest number required. Terminals are mounted on the head slider and are connected to the magnetic head unit. The terminals include at least one current-supplying terminal that is connected to the heat-generating element serving to control the flying height and to the high-frequency oscillator.03-05-2009
20090059416STORAGE DEVICE, STORAGE MEDIUM, AND METHOD FOR MANUFACTURING STORAGE MEDIUM - According to an aspect of an embodiment, an storage device includes a storage medium having a substrate, a storage medium layer for storing information, a first lubricating layer on a first area of the storage medium layer, and a second lubricating layer on a second area of the storage medium, the second lubricating layer having a viscosity lower than the first lubricating layer. The storage device further comprises a head for writing information into the storage medium layer or reading information from the storage medium layer.03-05-2009
20090059415STORAGE DEVICE AND SERVO INFORMATION WRITING METHOD - A storage device receives and holds a storage medium that is subjected to first servo writing processing for writing servo information, a Gray code of which is offset, from an inner cylinder or an outer cylinder to a predetermined cylinder and, after the first servo writing processing, subjected to second servo writing processing for writing servo information from an opposite direction to the predetermined cylinder and in which Gray codes are written to be offset not to overlap in the first or second servo writing processing and the pieces of servo information having different mark patterns are written in the first servo writing processing and the second servo writing processing. The storage device acquires cylinder information and mark patterns from the servo information written in the held storage medium and controls a position of a head based on the acquired cylinder information and mark patterns.03-05-2009
20090059414Hard disk drive with power saving feature - A hard disk drive with a head, and a disk that is rotated by a spindle motor. The drive includes a controller that operates in a low-speed idle mode where the spindle motor speed is reduced and the head is moved to a contact start-stop zone of the disk. Reducing the speed of the spindle motor, instead of spinning down the disk allows the disk drive to rapidly resume normal operation. Parking the head at a certain area of the disk, instead of a position off disk, allows the drive to more readily re-establish a mode where data can be retrieved or stored.03-05-2009
20090059412Extracting Position Information Using User Data - A method is disclosed for determining position information of a transducer. At least a first code and a second code are chosen. The first code has different characteristics than the second code. User data written to a first sub-track is encoded with the first code and user data written to a second sub-track is encoded with the second code. The first code read from the first sub-track is obtained and the second code read from the second sub-track is obtained. Position information of the transducer is extracted from the obtained characteristics of the first code and the obtained characteristics of the second code.03-05-2009
20120314320Erasure of Magnetic Storage Media having Perpendicular Anisotropy - Magnetic storage tape and techniques for erasing and writing to magnetic storage tape having a perpendicular squareness greater than 50 percent and a longitudinal squareness less than 50 percent are described. In general, the magnetic tape may be biased with a remanence magnetization, or magnetic orientation, in any direction. One or two head systems may use various magnetic field patterns to create the desired remanence magnetization. Servo marks may have a remanence magnetization in an opposite magnetic orientation than that of the remaining bias on the servo track, e.g., substantially perpendicular to the magnetic tape. In some examples, a write head may alternate the direction of the magnetic field to continuously bias and write servo patterns to the magnetic tape. In addition, a symmetrical servo mark may be created in the magnetic tape with a write head having a gap width approximately equal to the length of the servo mark.12-13-2012
20120075744METHOD OF OPTIMIZING FLYING HEIGHT OF HEAD AND HARD DISK DRIVE MANUFACTURED BY THE SAME - A hard disk drive includes a controller that optimizes a flying height of a head of a hard disk drive. The controller determines an optimal flying height of a head based on a preset table value and an MRR value of a head measured during a hard disk drive manufacturing process and sets the head according the determined optimal flying height such that recording capacitance is improved.03-29-2012
20120075743COMMUNICATION APPARATUS AND METHOD - According to one embodiment, a communication apparatus includes a storage unit, a state detecting unit, a communication unit, and a communication control unit. The storage unit configured to store information. The state detecting unit configured to detect, at least one time during an operation of the communication apparatus, whether the storage unit is in a busy state in which no data writing is allowed, or in a ready state in which data writing is allowed. The communication unit configured to perform communication with a destination communication apparatus. The communication control unit configured to control the communication unit to inform the destination communication apparatus that a data receiving operation is stopped for a first time period, if the state detection unit detects that the storage unit has entered the busy state.03-29-2012
20120075741Arm coil assembly, arm flexible cable assembly and disk drive unit with the same - An arm coil assembly includes a drive arm having at least two grounding pins formed on a mounting region thereof and a voice coil fixed on the tailing end of the drive arm for controlling the drive arm. The grounding pins are provided for electrically connecting with a flexible printed cable assembly by extending through at least two mounting holes formed on the flexible printed cable assembly. Each grounding pin has a slot formed thereon to clamp the flexible printed cable assembly. The arm coil assembly of the present invention having grounding pins with slot structure to clamp the flexible printed cable assembly which is mounted on the drive arm to form an arm flexible cable assembly, thus, the flexible printed cable assembly can be pre-mounted onto the arm coil assembly without using any additional fixtures or tools, therefore simplifying the mounting process and reducing the manufacturing cost thereof. The invention also discloses an arm flexible cable assembly and a disk drive unit including the same.03-29-2012
20100007983MAGNETIC RECORDING APPARATUS AND METHOD FOR POSITIONING HEAD - According to an aspect of the embodiment, a magnetic recording apparatus has a sensor detecting a first signal including disk flutter and arm flexural vibration and a sensor for detecting a second signal only including the arm flexural vibration. The magnetic recording apparatus obtains the frequency component of disk flutter based on the first signal and second signal, and executes the control of positioning a head based on the obtained frequency component of the disk flutter.01-14-2010
20100007982INFORMATION STORAGE APPARATUS - An information storage apparatus includes a housing; a recording medium in which information is recorded, disposed in the housing; a head that records/reproduces information onto/from the recording medium by making contact with or approaching to a surface of the recording medium; a head holding member for holding the head, being rotatable about a predetermined axis and moving the head along the recording medium; a driving section that drives the head holding member to rotate about the axis; a rotation restricting member disposed in a position where the head holding member collides, and that restricts a rotation area of the head holding member; a temperature change detecting section that detects temperature change in the housing; and a drive controlling section that causes the driving section to drive the head holding member to collide with the rotation restricting member, when a detection result by the temperature change detecting section indicates temperature change.01-14-2010
20120188664RADIAL POSITION SEEK TUNING FOR ACOUSTIC PERFORMANCE - Examples of the present invention relate to reduction in acoustic noise by tuning seek characteristics of a servo controller, depending on a radial position of a head relative to a disk. The servo controller can provide compensation for acoustic resonance modes.07-26-2012
20120257300METHOD OF MANUFACTURING MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING/REPRODUCING DEVICE - Provided is a method of manufacturing a magnetic recording medium capable of manufacturing at a high productivity a useful magnetic recording medium having high surface smoothness and excellent head floating characteristics. Such a method of manufacturing a magnetic recording medium includes: forming a magnetic layer on a nonmagnetic substrate; and partially injecting ions into the magnetic layer to modify magnetic characteristics at a location of the magnetic layer where the ions are injected and to form magnetically separated magnetic recording patterns, in which, when partially injecting ions into the magnetic layer, a carbon film is formed on the surface of the magnetic layer, the carbon film is partially thinned by patterning, and ions are partially injected into the magnetic layer through locations where the carbon film is thinned.10-11-2012
20120262819MAGNETIC HEAD WITH INTERCONNECT ELEMENT - A magnetic head in one embodiment includes a plurality of components separated from each other by insulative portions, one of the components being a substrate; at least one connective element electrically coupling the components together; and a chiplet having at least one of read transducers and write transducers. A magnetic head in another embodiment includes a plurality of components separated from each other by insulative portions; side bars flanking the substrate; and at least one connective element electrically coupling the components together. A magnetic head in another embodiment includes a plurality of components separated from each other by insulative portions; and at least one connective element electrically coupling the components together, wherein the at least one connective element is positioned in at least one of the insulative portions, the at least one connective element having no other function than to electrically connect the components adjacent thereto.10-18-2012
20120262818TAPE DRIVE SYSTEM - A tape drive system according to one embodiment includes a support for engaging a tape; and a head directly opposing the tape engaging portion of the support, the head being for performing at least one of reading from a tape and writing to a tape. During an operation period, the head is positioned such that at least one of the following occurs: the head does not contact the tape for a majority of the operation period; the head does not contact the tape for at least a portion of the operation period; and the head engages the tape for at least a portion of the operation period when the tape is lifted from the support by a cushion of air formed between the support and the tape, the head pressing the tape into the air cushion when engaging the tape.10-18-2012
20120081812System and Method for Improved Free Fall Detection - An information handling system includes a free fall sensing system having an amplifier and sampling circuit, a sampling data analyzer, a sampling clock duration controller, and a sampling clock generator. The amplifier and sampling circuit is configured to sample data signals from the free fall sensor based on an initial sampling signal and based on a variable sampling signal. The sampling data analyzer is configured to compare a magnitude of sampled data point to a predetermined magnitude, to output an alert signal when the magnitude of the sampled data point is below the predetermined magnitude. The sampling clock duration controller is configured to vary a duration and a frequency of a sampling signal control in response to the alert signal. The sampling clock generator is configured to send a variable sampling signal to the amplifier and sampling circuit in response to the variation of the duration and the frequency of the sampling signal control.04-05-2012
20120257299MAGNETIC RECORDING/REPRODUCING APPARATUS AND METHOD FOR DETERMINING MAGNETIC RECORDING CONDITION - A magnetic recording/reproducing apparatus 10-11-2012
20120257298TMR SENSOR FILM USING A TANTALUM INSERTION LAYER AND SYSTEMS THEREOF - In one embodiment, a tunnel magnetoresistance (TMR) head includes a lead layer above a substrate, a seed layer above the lead layer, an antiferromagnetic (AFM) layer above the seed layer, a first ferromagnetic layer above the AFM layer, a second ferromagnetic layer above the first ferromagnetic layer, a coupling layer between the first and second ferromagnetic layers, the coupling layer causing a magnetization of the second ferromagnetic layer to be coupled to a magnetization of the first ferromagnetic layer, a fixed layer above the second ferromagnetic layer, an insertion layer adjacent the fixed layer or in the fixed layer, a barrier layer above the fixed layer, a free layer above the barrier layer, and a cap layer above the free layer. In another embodiment, the insertion layer is from about 0.05 nm to 0.3 nm in thickness and includes Ta, Ti, Hf, and/or Zr, and the free layer includes CoFeB.10-11-2012
20120257297AIR-BEARING SURFACE OF HEAD FOR MINIMIZING CONTACT WITH DISK - Approaches for a head slider for use within a hard-disk drive. The head slider comprises an air bearing surface (ABS) and an electromagnetic transducer disposed at an air outflow end of the air bearing surface. The air bearing surface comprises an inner (ID) side rail proximate the inner diameter side and an outer (OD) side rail proximate the outer diameter side. The ID side rail is longer in length than the OD side rail. The physical dimensions of the ID side rail have a geometry that reduces a contact force between the head and the magnetic-recording disk when the head experiences a positive roll static attitude (RSA). The physical dimensions of the OD side rail have a geometry that reduces contact force between the head and the magnetic-recording disk when the head experiences a negative RSA.10-11-2012
20110122525MAGNETIC RECORDING MEDIUM USING LAYERS HAVING HIGHER- AND LOWER-HK ANISOTROPIC MAGNETIC FIELDS - According to one embodiment, a magnetic recording medium includes a magnetic recording layer formed above a substrate, comprising: a first magnetic layer formed from a [Co/Pt]05-26-2011
20100328811METHOD OF CONTROLLING READING OR WRITING OPERATION OF DISK DRIVE - A method of controlling a writing or reading operation of a disk drive. The method includes determining whether a writing control signal or a reading control signal, and a flying height control signal to control a flying height of a head are in enabled states, and when the writing control signal or the reading control signal and the flying height control signal are in the enabled states, performing the writing operation or the reading operation.12-30-2010
20100328809METHOD FOR REMOVING RESIST AND FOR PRODUCING A MAGNETIC RECORDING MEDIUM, AND SYSTEMS THEREOF - In one embodiment, a method for removing a resist includes irradiating, with an UV light having a wavelength of less than about 240 nm, a structure having a resist on a pattern surface in an atmosphere having oxygen. The resist is used as a mask as it remains above the pattern after the pattern has been transferred to a magnetic recording medium surface having a magnetic film thereon, and the irradiating is performed during production of the magnetic recording medium. In another embodiment, a method for forming a magnetic recording medium includes applying a resist to a surface of a magnetic film above a substrate, curing the resist by irradiating the resist with first UV light to form a pattern, transferring the pattern to the magnetic film using the pattern, and removing the resist by irradiating using second UV light having a shorter wavelength in an atmosphere including oxygen.12-30-2010
20080297940METHOD AND APPARATUS FOR CONTROLLING A NONVOLATILE MEMORY IN A DISK DRIVE - According to one embodiment, in a disk drive having a disk and a flash memory, the disk controller controls the timing of performing a block erase when the flash memory is accessed, so that this timing may differ from the timing of a seek operation that is performed when the disk is accessed. This prevents the current flowing in the disk drive from exceeding the maximum operating current.12-04-2008
20080297939Control circuit for implementing damage prediction diagnosis on read head element of magnetic head and protection operation on write data - The present invention predicts and diagnoses damage to a read head element of a magnetic head used in a magnetic storage device. The present invention includes a control circuit for implementing a write data protection operation and for implementing a write and read operation using a different magnetic head when damage to the read head element is predicted, so as to allow detection of write data using a read element of a different magnetic head. The control circuit includes a monitor configured to detect a voltage of a read head element of a magnetic head, a comparator that determines whether the detected voltage exceeds a threshold voltage, the threshold voltage preferably being less than a maximum tolerable voltage of the read head element, and a counter configured to count signals passing through the comparator.12-04-2008
20120320471ADAPTIVE LATTICE PREDICTIVE FILTER - An implementation of a circuit disclose herein comprises a vibration sensor circuit that generates a sensor signal from a disturbance signal, a lattice filter circuit that decorrelates the sensor signal to generate orthogonal backward prediction errors, and a multiple regression filter that estimates a disturbance correction signal using the orthogonal backward prediction errors.12-20-2012
20110038074Ramp for a hard disc drive - A moveable ramp arrangement having a traditional front side while the back side has an extended rotational park position used to support the read/write heads while the ramp is in the open position before and during disc installation.02-17-2011
20110235208METHOD OF DETECTING THE TOUCH-DOWN OF A HEAD, METHOD OF ADJUSTING A HEAD FLYING HEIGHT USING THE METHOD OF DETECTING THE TOUCH-DOWN OF THE HEAD, AND DISK DRIVE USING THE METHOD OF DETECTING THE TOUCH-DOWN OF THE HEAD - A method of detecting a touch-down of a head in a disk drive, a method of adjusting a head flying height by using the method of detecting a touch-down of a head, and a disk drive using the method of detecting a touch-down of a head detect a change of an electrical characteristic of a sensor installed in a slider, wherein the electrical characteristic changes according to temperature; and determines that the head flying height reached a touch-down flying height if the detected change of the electrical characteristic satisfies a threshold condition.09-29-2011
20110235207METHOD AND APPARATUS FOR DETECTING TOUCH-DOWN AND CONTACT BETWEEN A HEAD AND A STORAGE MEDIUM USING A SENSOR, AND A DRIVE DISK AND STORAGE MEDIUM USING THE METHOD - A method and apparatus for detecting a touch-down and contact between a head and a storage medium by using a signal generated by a data storage device, specifically by a sensor installed in a slider. The method includes: separating a signal detected by a sensor into a direct current (DC) component and an alternating current (AC) component, wherein the sensor has an electrical characteristic that changes according to temperature; using the DC component to detect a touch-down state of the head during a touch-down test to determine a value of a control signal for adjusting the flying height of the head; and using the AC component to detect a contacting state between the head and the storage medium in an operating state of the apparatus.09-29-2011
20100232054MAGNETIC RECORDING MEDIUM AND MAGNETIC STORAGE - An object of the invention is to provide a magnetic recording medium which exhibits an excellent corrosion resistance. To this end, proposed is a magnetic recording medium including a magnetic recording layer in which: a magnetic body and a filling body alternately appear along a recording surface; and a layer made of a passivated metal or an alloy containing at least one passivated metal is formed in an interface portion between an area of the magnetic body and an area of the filling body.09-16-2010
20100232053METHOD AND APPARATUS FOR CONTROLLING HEAD WITH SPIN-TORQUE OSCILLATOR IN A DISK DRIVE - According to one embodiment, a disk drive has a magnetic disk and a magnetic head having a spin-torque oscillator. The disk drive further has a head amplifier IC configured to supply a write signal and a drive signal to the magnetic head. The write signal corresponds to write data. The drive signal is supplied to generate a high-frequency magnetic field. The head amplifier IC continuously supplies a drive signal of normal level to the spin-torque oscillator, and supplies a drive signal of high level higher than the normal level, only for a prescribed time after the polarity inversion of the write signal.09-16-2010
20100232052PROCESS FOR PRODUCING MAGNETIC RECORDING MEDIUM AND MAGNETIC RECORDING/REPRODUCTION APPARATUS - Provided is a process for making a magnetic recording medium having a magnetically partitioned magnetic recording patterns, which comprises the following three steps (1), (2) and (3), conducted in this order: (1) a step of forming a magnetic layer on a non-magnetic substrate; (2) a step of removing surface layer portions of regions for magnetically partitioning the magnetic layer; and (3) a step of exposing the thus-exposed regions of the magnetic layer, from which the surface layer portions have been removed, to a reactive plasma or a reactive ion, to modify the magnetic characteristics of the regions of magnetic layer, whereby a magnetic recording pattern is formed which are magnetically partitioned by the regions of magnetic layer having the modified characteristics. Thus, a magnetic recording medium having an enhanced recording density and minimizing letter bleeding at writing can be made with a high efficiency.09-16-2010
20120087035Systems and Methods for Variable Compensated Fly Height Measurement - Various embodiments of the present invention provide systems and methods for determining fly height.04-12-2012
20120087034PERPENDICULAR MAGNETIC RECORDING MEDIUM AND MAGNETIC STORAGE APPARATUS USING THE SAME - According to one embodiment, a perpendicular magnetic recording medium includes a soft magnetic underlayer formed above a substrate, a lower seed layer formed above the soft magnetic underlayer, at least one upper seed layer formed above the lower seed layer, an interlayer formed above the at least one upper seed layer, a perpendicular recording layer formed above the interlayer, and a protective layer formed above the perpendicular recording layer, wherein the at least one upper seed layer comprises Ni or a Ni based alloy including N, and wherein the lower seed layer includes Ni and at least one element selected from a group consisting of: W and Cr. Other embodiments are described herein regarding perpendicular magnetic recording systems and methods of producing perpendicular magnetic media.04-12-2012
20120327532TANDEM MAGNETIC WRITER - A magnetic head in one embodiment includes a pole; a first write gap in the pole; a first coil for generating a magnetic flux across the first write gap; a second write gap in the pole having at least a portion thereof aligned with the first write gap in a direction parallel to a direction of media travel thereover; and a second coil for generating a magnetic flux across the second write gap, the second coil being addressable independently of the first coil. A method in one embodiment includes forming a first write coil; forming a first write gap; forming a second write gap; forming a second coil for generating a magnetic flux across the second write gap, the second coil being addressable independently of the first coil; and forming one or more write poles, wherein a write pole region adjacent the first and second write gaps is formed concurrently.12-27-2012
20120327531LOW PERMEABILITY MATERIAL FOR A SIDE SHIELD IN A PERPENDICULAR MAGNETIC HEAD - In one embodiment, a perpendicular magnetic head includes a main magnetic pole, a side shield disposed on both sides of the main magnetic pole in a track width direction, the side shield including a material having a saturation magnetic flux density of no greater than about 1.0 T, and a trailing shield disposed on a trailing side of the main magnetic pole, wherein the trailing shield and the side shield are physically separated from one another. In another embodiment, the side shield includes a first magnetic film, and the trailing shield includes a second magnetic film, wherein a magnetic permeability of the first magnetic film is lower than a magnetic permeability of the second magnetic film.12-27-2012
20120287531EMBEDDED CHIP TAPE HEAD - A tape drive system according to one embodiment includes a magnetic head. The magnetic head includes first and second beams each having a tape bearing surface, a face, a recess in the tape bearing surface thereof, the faces of the beams facing either towards each other or away from each other; a first chip being positioned in the recess of the first beam; and a second chip being positioned in the recess of the second beam, wherein each chip has circuitry selected from a group consisting of read elements, write elements, and combinations thereof, wherein a tape bearing surface of each chip is generally aligned with the tape bearing surface of the associated beam, and wherein an end of each chip is generally aligned with the face of the associated beam. The system also includes a drive mechanism and a controller.11-15-2012
20120140357MAGNETIC RECORDING MEDIUM HAVING RECORDING REGIONS AND SEPARATING REGIONS AND METHODS OF MANUFACTURING THE SAME - In one embodiment, a method for forming a magnetic recording medium includes forming a protective layer above reading regions of a patterned magnetic recording layer and separating regions between the recording regions, wherein the protective layer forms on sides of the recording regions and partially fills the separating regions, and forming a filler layer on the protective layer, wherein the filler layer completely fills the separating regions, wherein the filler layer has an uneven upper surface. In another embodiment, a medium includes a patterned magnetic recording layer, a protective layer above the patterned magnetic recording layer and on sides of the patterned magnetic recording layer, and a filler layer positioned between the patterned magnetic recording layer in separating regions, wherein DLC of the filler layer is a lower density than DLC of the protective layer. Other systems and methods are described according to more embodiments.06-07-2012
20100142081MAGNETIC DISK DEVICE, ACTUATOR ARM, AND SUSPENSION - According to one embodiment, a magnetic disk device includes a magnetic disk, a magnetic head, and an actuator. The magnetic disk stores data. The magnetic head floats due to an air flow produced by the rotation of the magnetic disk to write and read data to and from the magnetic disk. The actuator includes a suspension and an actuator arm. The suspension supports the magnetic head. The actuator arm supports the suspension. The actuator is provided with a strip projection, a bump, a plurality of projections, or a concave portion on the upstream side of an air flow produced by the rotation of the magnetic disk.06-10-2010
20130016441RECORDING HEAD AND DISK DRIVE PROVIDED WITH THE SAMEAANM Taguchi; TomokoAACI Kunitachi-shiAACO JPAAGP Taguchi; Tomoko Kunitachi-shi JPAANM Tomoda; YusukeAACI Zama-shiAACO JPAAGP Tomoda; Yusuke Zama-shi JP - According to one embodiment, a recording head includes a main pole, a trailing shield including a first connecting portion and a second connecting portion, and configured to form together with the main pole a first magnetic core, a leading shield including a first connecting portion connected to the main pole through a magnetic material and an end portion opposing to the end portion of the main pole through a non-magnetic material, and configured to form together with the main pole a second magnetic core, and first and second coils wound around the first and second magnetic cores, and a connection terminal configured to flow a current through the main pole, non-magnetic conductive layer, and trailing shield.01-17-2013
20130016440BASE FOR MOTOR AND HARD DISK DRIVE INCLUDING THE SAMEAANM CHOI; Tae YoungAACI YonginAACO KRAAGP CHOI; Tae Young Yongin KR - There is provided a base for a motor, the base including: a base body having a disk disposed thereon; and an outer wall part formed on the base body to thereby define an outer edge thereof, wherein the outer wall part includes at least one cut wall part formed by cutting a predetermined region and an outer side wall part formed by bending a region other than the cut wall part.01-17-2013
20110157740FLY-HEIGHT MANAGEMENT IN A HARD DISK DRIVE (HDD) - A hard disk drive (HDD) including a first resistive temperature detector (RTD) configured to detect a temperature generated by proximity of a slider and a media. The first RTD is proximate an air bearing surface (ABS) of the slider. The HDD also includes a second RTD configured to detect at least one temperature correlated to a fly-height of the slider. The second RTD is not required to be proximate the ABS of the slider. HDD also includes a read/write integrated circuit (IC) configured to determine the fly-height of the slider based on detection of temperatures by the first RTD and the second RTD.06-30-2011
20110157739NEGATIVE BIASING A SLIDER WITH RESPECT TO A DISK TO REDUCE SLIDER WEAR AND PROVIDE BURNISH RATE CONTROL - In a method for negatively biasing a slider with respect to a disk to reduce slider wear and provide burnish rate control a negative bias voltage is generated between the slider and the disk surface respectively, the negative bias voltage causing slider/disk contact wear to occur on the disk instead of on the slider.06-30-2011
20080253015SYSTEM AND METHOD FOR DETECTING SHAKES AND PERCUSSIVE IMPACTS AND FOR PROTECTING PORTABLE ELECTRONIC DEVICES WHEN PRE-SPECIFIED SHAKE PATTERNS AND PERCUSSIVE IMPACT LEVELS ARE DETECTED - A system and method detects low grade physical motions of an electronic device, such as a laptop computer, and takes protective measures if the physical motions match a pre-specified physical motion pattern. The pre-specified physical motion pattern may have been selected as a pattern which, if left alone, could cause cumulative damage to the electronic device. Alternatively, the pre-specified motion pattern may have been selected as a pattern which tended to indicate that more aggressive and abrupt movements would be forthcoming. The system and method further detects sustained motion (such as in a laptop bag) such that the laptop may shut-off so that the laptop does not overheat or get damaged. The system and method may be configured such that a system administrator may be notified if laptop is being abused. In a similar manner, the history of the percussive impacts or movements may be kept or logged for future use.10-16-2008
20080247080HARD DISK DRIVE HAVING IMPROVED HEAD STABILITY AT LOW TEMPERATURE AND METHOD OF APPLYING CURRENT TO A HEAD OF THE HARD DISK DRIVE - A hard disc drive (HDD) that has improved head stability at low temperatures and a method of supplying current to a head of the HDD. The HDD includes a disc, a tunneling magneto resistance (TuMR) head to read data recorded on the disc having a heating coil, and a current control unit to supply a current corresponding to the ambient temperature surrounding the HDD to the heating coil. The current control unit supplies a current corresponding to the ambient temperature to the heating coil of the head. Since a heating coil is inserted in the TuMR head, an optimum current corresponding to the ambient temperature can be supplied to the heating coil, and thus, the head instability during a reading operation at low temperatures can be prevented.10-09-2008
20080247078Altitude sensing systems and methods for fly height adjustment - Altitude sensing systems and/or methods for fly height adjustment in disk drive devices are provided. In certain example embodiments, a PZT-type pressure and/or altitude sensor may be located on the side of the disk drive proximate to the disk edge. When the disk rotates, the air flow generated by the disk will deform the PZT element of the sensor. The PZT element will generate a voltage in response to this deformation. Calibrations may be performed to compensate for altitude changes (e.g. the air inside of the disk drive will become thin and the air resistance will be reduced at higher altitudes). Also, the output sensitivity of the PZT element may change with the altitude change. After the altitude is sensed by the PZT element in the sensor, the servo motor may use this signal to calculate and/or adjust the dynamic fly height (DFH) and/or fly height of the read/write head.10-09-2008
20080225429METHOD OF REDUCING ABRASION OF DISK BY USING DITHERING PROCESS AND DISK DRIVE USING THE SAME - Embodiments of the invention reduce abrasion of a disk via a dithering process that spreads a friction area between a magnetic head and the disk when a magnetic head lifts from the surface of the disk. In embodiments of the invention, the dithering process is executed only when the magnetic head is latched in a parking zone of the disk and when a disk spindle motor is in an acceleration mode.09-18-2008
20090086360Low Complexity Servo Demodulation Algorithm for Probe Storage - A method of calculating a position error signal is provided. The method includes receiving an analog signal from a data channel and converting the analog signal to a one bit wide digital signal. The analog signal is converted to a digital signal at an oversampled frequency. The position error signal is then calculated by summing correlated oversampled digital signals.04-02-2009
20100085658STORAGE DEVICE CONTROLLING DEVICE, STORAGE DEVICE, STORAGE DEVICE CONTROLLING PROGRAM, AND STORAGE DEVICE CONTROLLING METHOD - A storage device controlling device includes: a head sector generation section that creates predetermined information different from control information to be read out first from plural storage media; an input/output section that writes the control information into a head sector on the storage media; a reception section that receives an access request from outside; and a conversion section that converts a first sector number as a sector number on the plural storage media into a second sector number as a sector number other than that of the head sector on the plurality of storage media, based on a predetermined conversion method, the first sector number being designated by the access request, and the input/output section further accesses the plural storage media at the second sector number.04-08-2010
20080225430Method for specifying control value for controlling clearance adjustment amount between head and disk, disk drive device and manufacturing method thereof - Embodiments of the present invention help to reduce damage of a head element portion or a magnetic disk in a procedure for specifying a heater power value for adjusting a clearance between the head element portion and the magnetic disk. In an embodiment of the present invention, an HDC/MPU sequentially performs data writing and reading while increasing heater power. The HDC/MPU further determines whether or not a head slider has retrieved the data properly. When the data cannot be retrieved properly, the HDC/MPU specifies a heater power value in a normal operation based on the heater power value at which the data could not be retrieved properly.09-18-2008
20080225428STORAGE DEVICE, CONTROL DEVICE, AND VIBRATION-DETECTION METHOD - A storage device positions a head at a predetermined position on a storage medium by driving an actuator with the head and at least writes data onto the storage medium. The storage device includes a vibration sensor, a filter for outputting a signal of a frequency band centered on a first frequency from an output of the vibration sensor, and a write-protection-determination unit for protecting against data-writing processing upon a value of the output of the filter being larger than a threshold value.09-18-2008
20080225427Dynamic flying height design with off-track contact capability at touch down in hard disk drives - Dynamic fly height (DFH) control is obtained for a read/write head by use of a heating element having two laterally separated heat sources symmetrically spaced around the track center line of the head. The two heating sources create a protrusion profile relative to the undistorted ABS that recesses the read element and main write pole at the track center line relative to off-track positions. The resulting DFH control also protects the head from HDI events that are either the result of calibration procedures or normal HDD operation.09-18-2008
20130170069LOAD-UNLOAD RAMP STRUCTURE WITH CANTILEVERED FIN PORTION CONFIGURED TO REDUCE DROP SHOCK IN A HARD-DISK DRIVE - A load-unload ramp structure with a cantilevered fin portion to reduce drop shock in a hard-disk drive (HDD). The load-unload ramp structure includes a first load-unload ramp, a fin, and a bracket portion. The first load-unload ramp is configured to lift a first head-slider away from a magnetic-recording disk. The fin is coupled to the first load-unload ramp and is disposed below a first parking position of the first head-slider. The fin includes a fin base portion and a first cantilevered fin portion. The first cantilevered fin portion is coupled to, and extends outward from, the fin base portion. The bracket portion is integrally attached to the first load-unload ramp, and is configured to allow affixing the load-unload ramp structure in a static position in a disk-enclosure base of the HDD. A HDD including the load-unload ramp structure and a method for providing protection from drop shock are also provided.07-04-2013
20130170070MAGNETIC-RECORDING HEAD WITH TOUCH-DOWN DETECTOR INCORPORATING A CARBON NANO-TUBE - A magnetic-recording head with touch-down detector incorporating a carbon nano-tube (CNT). The magnetic-recording head includes a write element, a read element and a touch-down detector. The write element is configured to write data to a magnetic-recording disk. The read element is configured to read data from the magnetic-recording disk. The touch-down detector includes a thermal sensor, and a CNT portion. The thermal sensor is configured to convert heat to a voltage signal. The CNT portion is configured to touch down on the magnetic-recording disk. The CNT portion is also coupled to the thermal sensor, and is configured to transfer heat generated by contact between the CNT portion and the magnetic-recording disk to the thermal sensor. A hard-disk drive (HDD) including the magnetic-recording head with touch-down detector incorporating a CNT, and a method for detecting contact between the magnetic-recording head and a recording surface of a magnetic-recording disk are also provided.07-04-2013
20130170071DETECTING TOUCH DOWN AND/OR ASSESSING QUALITY IN A HARD DISK DRIVE - This application discloses a hard disk drive and a control circuit that are configured to determine touchdown by determining the SAGC for a track, removing the repeatable component of the SAGC to create the non-repeatable component and determining an indication of clearance irregularity and/or touch down when the standard deviation of the non-repeatable component spikes. These operations may create a defect map and/or a Flying height On Demand (FOD) control table in or for the hard disk drive as products of operating the hard disk drive.07-04-2013
20130170072INTEGRATED RECORDING HEAD WITH SELECTIVE MOVEMENT - In one example, a head is provided that may include a slider body, a transducer body, a transducer connected to the transducer body, and an interleaver assembly interconnecting the slider body and the transducer body. The interleaver assembly may include an interleaver body to which the transducer body is attached, the interleaver body having a plurality of geometric features that enable temporary deformation of the interleaver body in response to exertion of a force on the interleaver body, and the interleaver body may further include piezoelectric elements positioned in the interleaver body, the piezoelectric elements operable such that, when selectively actuated, the piezoelectric elements exert a force on the interleaver body so as to effect selective movement of the transducer with respect to a surface of a medium.07-04-2013
20120250180MAGNETIC HEAD - According to one embodiment, a magnetic head for reading data from a magnetic recording medium by utilizing a magnetic resonance phenomenon includes an auxiliary magnetic pole, a first oscillator, and a second oscillator. The auxiliary magnetic pole is to apply a magnetic field to the magnetic recording medium. The first oscillator is to oscillate at a first frequency and apply, to the magnetic recording medium, a first high-frequency magnetic field corresponding to the first frequency. The second oscillator to oscillate at a second frequency different from the first frequency and apply, to the magnetic recording medium, a second high-frequency magnetic field corresponding to the second frequency.10-04-2012
20130114160BASE FOR MOTOR AND HARD DISK DRIVE INCLUDING THE SAME - There is provided a base for a motor, the base including: a base body formed by performing press processing on a steel plate, a base material; an outer wall part defining an outer edge of the base body and formed by being bent from an end portion of the base body; and at least one weight reducing part formed by removing a predetermined region of the outer wall part.05-09-2013
20130114161Data Storage System and a Method for Measuring a Change in a Spacing Between a Head and a Storage Medium of a Data Storage System - A method for measuring a change in a spacing between a head and a storage medium of a data storage system. The method includes obtaining a first readback signal from the storage medium using the head at a first spacing between the head and the storage medium, determining a first power spectrum density over a frequency range from the obtained first readback signal, obtaining a second readback signal from the storage medium using the head at a second spacing between the head and the storage medium, determining a second power spectrum density over the frequency range from the obtained second readback signal, and providing a measurement indicative of the change in the spacing based on the determined first power spectrum density and the determined second power spectrum density. A data storage system is also provided.05-09-2013
20130100554TAPE DRIVE HEAD WITH JOINTLY OPTIMIZED SHIELD-TO-SHEILD GAP AND SENSOR WIDTH - A tape drive head includes a set of one or more servo readers designed for reading a servo pattern of a linear recording tape for positioning of the tape drive head, each of the servo readers of the set having: a sensor for sensing a magnetic field component of a servo pattern upon reading it; a first shield and a second shield, one on each side of the sensor, the shields configured to shield spurious components of magnetic fields occurring upon reading the linear recording tape, wherein: a gap between the first shield and the second shield is between 0.4 μm and 1 μm, and a minimal width of the sensor, the first shield and the second shield, in a direction perpendicular to the gap, is between 0.5 μm and 4 μm.04-25-2013
20130120872MAGNETIC WRITER HAVING MULTIPLE GAPS WITH MORE UNIFORM MAGNETIC FIELDS ACROSS THE GAPS - A magnetic device according to one embodiment includes a source of flux; a magnetic pole coupled to the source of flux, the magnetic pole having two or more gaps; and a low reluctance path positioned towards at least one of the gaps and not positioned towards at least one other of the gaps for affecting a magnetic field formed at the at least one of the gaps when the source of flux is generating flux. Other disclosed embodiments include devices having coil turns with a non-uniform placement in the magnetic yoke for altering a magnetic field formed at the at least one of the gaps during writing. In further embodiments, a geometry of the magnetic pole near or at one of the gaps is different than a geometry of the magnetic pole near or at another of the gaps to help equalize fields formed at the gaps when the source of flux is generating flux.05-16-2013
20130120871BASE ASSEMBLY FOR MOTOR AND HARD DISK DRIVE INCLUDING THE SAME - There is provided a base assembly for a motor, the base assembly including: a base body having a disk disposed thereon; an outer wall part defining an outer side of the base body; one or more ribs depressed from one surface of the base body and protruded toward the other surface thereof to thereby improve rigidity of the base body; and one or more blocking parts provided in the ribs to thereby block abnormal air flow due to the ribs at a time of rotation of the disk.05-16-2013
20130120870DISK DRIVE SELECTING DISTURBANCE SIGNAL FOR FEED-FORWARD COMPENSATION - A disk drive is disclosed comprising a disk, a head, and control circuitry comprising a servo control system operable to actuate the head over the disk. A plurality of disturbance signals is generated in response to a vibration. A plurality of correlations is generated in response to each disturbance signal and an error signal of the servo control system. At least one of the disturbance signals is selected in response to the correlations. A feed-forward compensation value is generated in response to the selected disturbance signal, and the feed-forward compensation value is applied to the servo control system to compensate for the vibration.05-16-2013
20130120869PERPENDICULAR MAGNETIC WRITE HEAD HAVING A CURRENT CARRYING ELEMENT FOR IN-PLANE FIELD ASSISTED MAGNETIC RECORDING - In one embodiment, a magnetic head includes a main pole configured to produce a magnetic writing field applied to a magnetic medium at an overall angle with respect to a magnetic anisotropy axis which is oriented in a direction perpendicular to a plane of a surface of the magnetic medium, and at least one current carrying element positioned near a media facing surface of the main pole configured to produce an assisting magnetic field applied in a cross-track direction parallel to the plane of the surface of the magnetic medium. In another embodiment, a method includes applying a writing magnetic field to write data to a magnetic medium and applying an assisting magnetic field to the magnetic medium for assisting the writing magnetic field, the assisting magnetic field being applied in a cross-track direction of the magnetic medium and parallel to a plane of a surface of the magnetic medium.05-16-2013
20130128382SUSPENSION WITH HIGH CONDUCTIVITY GROUND LAYER - A suspension is configured to support a magnetic head slider having a recording head element for recording to a magnetic recording medium and a microwave generating element that applies a high-frequency magnetic field to the magnetic recording medium when recording to the magnetic recording medium is conducted by the recording head element. The suspension includes a flexure that supports the magnetic head slider, and a microwave signal transmission line and a recording signal transmission line that are supported by the flexure. The microwave signal transmission line is connected to the microwave generating element and configured to transmit microwave signals for generating the high-frequency magnetic field, the recording signal transmission line being connected to the recording head element and configured to transmit recording signals. The flexure has a main body part, a support part for the magnetic head slider, and a pair of arm parts that links the main body part and the support part. The recording signal transmission line is supported between the main body part and the support part by a separate support part separated from the flexure, the microwave signal transmission line is supported between the main body part and the support part by at least one of the pair of arm parts, and a portion of the one of the arm parts that supports the microwave signal transmission line has a lamination structure in which an insulating layer that supports the microwave signal transmission line on one surface and a substrate whose portion opposing the other surface of the insulating layer has conductivity are laminated.05-23-2013
20080204923BURN-IN PROCESS OF PRODUCING DATA CORRELATING ELEVATION OF DISK DRIVE HEAD TO TEMPERATURE AND METHOD OF CONTROLLING THE ELEVATION OF THE DISK DRIVE HEAD USING THE DATA - Data characterizing a read/write head of a hard disk drive is produced in a burn-in process. The method includes measuring the flying height of the head at a first temperature in a burn-in chamber, measuring the flying height of the head at a second temperature in the burn-in chamber, postulating a linear relationship between the flying height and the temperature of ambient air using values of the flying height measured at the first and second temperatures, and estimating the flying height of the head at a third temperature using the linear relationship. The elevation of the read/write head is then controlled based on data representing the values of the flying height as measured at the first and second temperatures and as estimated for the temperature. In particular, the amount of electric power supplied to an FOD heater of the head is controlled based on the data generated during the burn-in process.08-28-2008
20080266703HARD DISK DRIVE APPARATUS, METHOD OF CONTROLLING FLYING HEIGHT OF MAGNETIC HEAD THEREOF, AND RECORDING MEDIUM TO CONTAIN COMPUTER PROGRAM THEREFOR - A method of controlling a flying height of a magnetic head of a hard disk drive includes determining whether a difference between a measured flying height of the magnetic head measured by applying a burn-in FOD (flying on demand) voltage corresponding to a target flying height, according to a reference FOD voltage profile defining a relationship between the flying height of the magnetic head and the FOD voltage by which an end of the magnetic head thermally expands and thus protrudes, to a heater included in the magnetic head, and a burn-in flying height of the reference FOD voltage profile corresponding to the burn-in FOD voltage exceeds a preset reference, calculating a corrected FOD voltage for the target flying height by performing a touch down test of the magnetic head with respect to a disk, when the difference between the measured flying height of the magnetic head and the burn-in flying height exceeds the preset reference, and controlling a flying height of the magnetic head by applying the corrected FOD voltage. An FOD voltage can be applied in a variety of environments to substantially maintain the target FH of the magnetic head.10-30-2008
20110211277DETECTING CIRCUIT AND INSPECTING APPARATUS - A detecting circuit, which can detect plural types of servo signals, including a cosine/sine value detector for sampling a servo signal supplied from an inspected object and thereby obtaining a cosine value and a sine value, an amplitude/phase detector for obtaining at least amplitude information and phase information on the basis of the cosine value and the sine value obtained by the cosine/sine value detector, and a servo selector/position detector for selecting a servo scheme of the inspected object and detecting a position of the inspected object on the basis of the amplitude information and the phase information obtained by the amplitude/phase detector.09-01-2011
20110211276METHOD AND APPARATUS FOR CONTROLLING HEAD FLYING HEIGHT IN A DISK DRIVE - According to one embodiment, a disk drive includes a measuring module, a flying height controller, a detection module, and a controller. The measuring module is configured to measure the flying height that the head has with respect to the disk. The flying height controller is configured to control the head flying height in accordance with a value preset for the head flying height. The detection module is configured to detect the values representing the environmental elements of the head. The controller is configured to adjust the preset value in accordance with the flying height measured by the measuring module and values detected by the detection module if environmental changes are detected from the environmental element values output from the detection module.09-01-2011
20110222186MAGNETIC RECORDING DEVICE, MAGNETIC RECORDING METHOD, AND MAGNETIC STORAGE MEDIUM - According to one embodiment, a magnetic recording device based on shingled-write recording method comprises a magnetic storage medium, a recording head, and an actuator. The magnetic storage medium comprises dot rows wherein a phase shift is between adjacent rows. The recording head covers a predetermined number of dot rows of the magnetic storage medium and comprises an edge at one of the dot rows. The actuator configured to move a recording head by an amount equivalent to a dot row after recording is performed on one of the dot rows by the recording head.09-15-2011
20080198499Continuous mode velocity control of voice coil motor - A method of controlling the velocity of a voice coil motor (VCM), including sensing a voltage difference between the VCM and a sense resistor and driving a velocity control loop (VCL) based on the voltage difference. There is also a control loop circuit, including a current output connected to drive a voice coil motor, the voice coil motor producing a back electromagnetic field (BEMF) voltage. The circuit also includes a sense resistor connected to the BEMF output, and a BEMF resistive network comprising a first resistor and a second resistor. The circuit also includes a velocity control loop (VCL) connected to control the voltage output according to a voltage difference between (i) a junction of the sense resistor and the current output and (ii) a junction of the first resistor and the second resistor.08-21-2008
20130148234HARD DISK DRIVE WITH WRITE ASSIST BASED ON DETECTED CONDITIONS - In one embodiment, a hard disk drive includes a magnetic disk medium, a magnetic head adapted for writing data to the magnetic disk medium, a mechanism (such as a detection circuit) adapted for detecting at least one recording condition of drive current provided to the magnetic head during writing operations, and an energy conversion element for controlling at least one recording characteristic of the magnetic head in response to the at least one detected recording condition. According to another embodiment, a method includes writing data to a magnetic medium using a magnetic head, detecting at least one recording condition of drive current provided to the magnetic head during the writing, and controlling at least one recording characteristic of the magnetic head during the writing using an energy conversion element in response to the at least one detected recording condition.06-13-2013
20130148235MAGNETIC TAPE DEVICE AND METHOD FOR CONTROLLING MOVEMENT OF MAGNETIC HEAD - A magnetic head is arranged between two reels around which a magnetic tape is wound and contacts one side of the magnetic tape spanned between the two reels. A driver moves the magnetic head. A controller causes the driver to generate a driving force for pressing the magnetic head against the one side of the magnetic tape while keeping the magnetic head in contact with the magnetic tape. It is possible to cause the magnetic head to stably contact the magnetic tape even when the running position of the magnetic tape varies in accordance with the winding state of the magnetic tape around the reel.06-13-2013
20130148236DATA STORAGE DEVICE AND A METHOD FOR PROVIDING A SYNCHRONIZATION SIGNAL FOR AT LEAST ONE OF A READ OPERATION OR A WRITE OPERATION CARRIED OUT BY MEANS OF A HEAD IN A DATA STORAGE DEVICE - According to embodiments of the present invention, a method for providing a synchronization signal for at least one of a read operation or a write operation carried out by means of a head in a data storage device is provided. The method includes obtaining a readback servo signal from a storage medium of the data storage device by means of the head, the readback servo signal having at least one frequency associated with a servo track of the storage medium, frequency mixing the readback servo signal with a local signal having a local frequency to provide a frequency mixed signal, and filtering the frequency mixed signal to provide the synchronization signal for at least one of the read operation or the write operation. According to further embodiments of the present invention, a data storage device is also provided.06-13-2013
20130148237MAGNETIC TAPE HEAD HAVING LUBRICANT IN RECESSED PORTIONS OF A TAPE BEARING SURFACE THEREOF, AND SYSTEMS HAVING THE HEAD - A magnetic tape head according to one embodiment includes a first section having a tape bearing surface (TBS) and portions that are recessed from the TBS; a thin film section coupled to the first section, the thin film section comprising transducers for at least one of reading from and writing to a magnetic tape; and a lubricating layer above at least the first section. Additional systems and methods are also disclosed.06-13-2013
20100284107METHOD OF CONTROLLING FLYING HEIGHT OF MAGNETIC HEAD AND DISK DRIVE USING THE METHOD - The flying heights of magnetic heads of a disk drive are set using an FOD (flying on demand) method in a bank mode. A first signal for adjusting the flying height of a magnetic head is issued to each magnetic head and the value of the first signal is scaled by scale values set for the magnetic heads, respectively, with one of the scale values differing from the others. The value of the first signal is changed until the magnetic head associated with the scale value different from the others touches down. A flying height for the magnetic head which touched down is determined based on the value of the first signal at the time of touch-down. The process is repeated, however with a different bank of scale values each time and set in such a way as to cause the sequential touch-down of the remaining magnetic heads, and determinations of flying heights for the magnetic heads.11-11-2010
20120257301APPARATUS AND METHOD FOR WRITING DATA TO TAPE MEDIUM - In a controller of a tape drive, a command processing unit receives a request to write new data, an offset determination unit determines whether old data is not partially overwritten with new data, and if old data is not partially overwritten with new data, a head position management unit makes a write head offset toward the unoverwritten portion. Then, a channel input/output unit reads pattern data that disables old data from a pattern storage unit and outputs the data to the write head to thereby overwrite the old data with the pattern data. After that, a tape transport management unit rewinds a tape and the head position management unit returns the write head to the original position to overwrite the old data with the new data as usual.10-11-2012
20080297938Erase band compensated offset servo trimming - A hard disk drive with a disk that has a servo field with an A servo burst and a B servo burst. The A servo burst has a trimmed erase band. The trimmed erase band can be created by offsetting the write head relative to a burst centerline to reduce the width of the erase band. For example, the write head can be moved toward a centerline of the A servo burst. The offset can be a function of write current and cylinder location of the disk. The offsets are selected so that the resultant burst profiles do not contain a flat minimum portion.12-04-2008
20100309580Perpendicular Magnetic Recording Medium Having FCC Seed Layers - According to one embodiment, a perpendicular magnetic recording medium includes at least one soft magnetic underlayer above a substrate, a seed layer above the at least one soft magnetic underlayer, an intermediate layer above the seed layer, a magnetic recording layer above the intermediate layer, and an overcoat layer above the magnetic recording layer, wherein the seed layer includes a second seed layer above a first seed layer. In another embodiment, the seed layer is a multilayered structure of at least two cycles of a unit of layered film which includes a first seed layer and a second seed layer. The first seed layer includes a non-magnetic alloy having a Face-Centered-Cubic (FCC) structure, and the second seed layer includes a soft magnetic alloy having a FCC structure. Other structures are also disclosed, according to more embodiments.12-09-2010
20100309579DUAL STAGE HEAD ACTUATOR ASSEMBLY FOR TAPE DRIVE - An actuator assembly (12-09-2010
20100309578METHOD AND APPARATUS FOR ESTIMATING FLYING HEIGHT IN A HARD DISK DRIVE - This application discloses a hard disk drive and operates it based upon using a first and third harmonic amplitude generated from reading a repeated pattern of bits written to a track on a disk surface. Both amplitudes are used to create a first data set and the third harmonic amplitude is used as a single tone to create a second data set. A conversion factor between these two is determine, which may be used to convert the first data set under other conditions into a temperature insensitive table of the electrical stimulus of a vertical micro-actuator and the flying height change of the slider. The hard disk drive may be calibrated during manufacture and/or in the field.12-09-2010
20100309577MICROWAVE-ASSISTED MAGNETIC RECORDING WITH COLLOCATED MICROWAVE AND WRITE FIELDS - Methods and devices are provided for microwave-assisted magnetic recording with collocated microwave and write fields. An illustrative device includes a magnetic write pole and one or more alternating-field components. The magnetic write pole is configured for providing a magnetic write field. The one or more alternating-field components are disposed to at least partially coincide with the magnetic write pole. The one or more alternating-field components are configured to provide an alternating magnetic field having a microwave frequency and an orientation that is at least partially transverse to the magnetic write field.12-09-2010
20100309576PATTERNED MEDIA MAGNETIC RECORDING DISK DRIVE WITH WRITE CLOCK PHASE ADJUSTMENT FOR WRITE HEAD TRACK MISREGISTRATION - A patterned-media magnetic recording disk drive has compensation for write head track misregistration (TMR) from the track centerline. As the disk rotates, the read head detects angularly spaced servo sectors and generates a position error signal (PES) which is used by the servo control system to maintain the read head on track. As the disk rotates, the read head also detects angularly spaced synchronization marks, which are used to control the write clock so that magnetization reversal of the magnetic write field from the write head is synchronized with the position of the data islands. If there is TMR of the write head, there will be an effective shift of A(p in the timing of when the center of the data islands pass through the write field. The disk drive includes write clock phase adjustment circuitry that correlates the PES with Δφ to compensate for TMR of the write head.12-09-2010
20090296259AUTOMATIC GAIN CONTROL FOR MAGNETIC DISK-DRIVE PREAMPLIFIER - One embodiment of the invention includes a preamplifier system for a magnetic disk-drive. The system comprises a read amplifier configured to generate a read signal corresponding to data that is read from a magnetic disk via a magneto-resistive (MR) read head. The system also comprises a gain control amplifier that is configured to amplify the read signal based on a digital gain value to generate an amplified read signal. The system further comprises a feed-forward automatic gain controller (AGC) configured to set the digital gain value based on an amplitude of the read signal.12-03-2009
20130155542PERPENDICULAR MAGNETIC RECORDING MEDIUM WITH GRAIN BOUNDARY CONTROLLING LAYERS - In one embodiment, a perpendicular magnetic recording medium includes an oxide recording layer including an oxide and a non-oxide recording layer which does not contain an oxide positioned above the oxide recording layer. The oxide recording layer includes a region R06-20-2013
20130155543PATTERNED MAGNETIC RECORDING MEDIA AND METHODS OF PRODUCTION THEREOF UTILIZING CRYSTAL ORIENTATION CONTROL TECHNOLOGY - In one embodiment, a patterned magnetic recording medium includes an interlayer positioned above a nonmagnetic substrate, wherein portions of the interlayer have good crystal orientation separated by portions of the interlayer which have poor crystal orientation, and a magnetic recording layer positioned above the interlayer. The magnetic recording layer is defined by a pattern which includes magnetic portions having good crystal orientation above the portions of the interlayer having good crystal orientation separated by magnetic portions having poor crystal orientation above the portions of the interlayer having poor crystal orientation. In another embodiment, a method is proposed for producing the patterned magnetic recording medium as described above which includes forming an interlayer and a recording layer above the interlayer, and imparting a template pattern to the interlayer using an organic resist during or after formation of the interlayer. The interlayer is adapted for controlling crystal orientation of the recording layer.06-20-2013
20130155544SHIELD STRUCTURE FOR REDUCING THE MAGNETIC INDUCTION RATE OF THE TRAILING SHIELD AND SYSTEMS THEREOF - In one embodiment, a magnetic head includes a main magnetic pole, a trailing shield positioned on a trailing side of the main magnetic pole, a trailing gap positioned between the trailing shield and the main magnetic pole, side shields positioned on either side of the main magnetic pole in a cross-track direction, side gaps positioned between the side shields and the main magnetic pole on either side of the main magnetic pole in the cross-track direction, and trailing shield gaps positioned on either side of the main magnetic pole in the cross-track direction between the trailing shield and the side shields, wherein the trailing shield gaps extend beyond the side gaps in a direction parallel to the cross-track direction. In addition, a method for producing a magnetic head as described above is also disclosed, according to one embodiment.06-20-2013
20110310505MAGNETIC STORAGE DEVICE CAPABLE OF RECORDING DROP HEIGHT AND ELECTRONIC DEVICE USING THE SAME - A magnetic storage device capable of recording a drop height and an electronic device using the same are presented. The magnetic storage device includes: a G-sensor, installed in the magnetic storage device, for outputting a first trigger signal when the magnetic storage device starts to drop and outputting a second trigger signal when the magnetic storage device stops dropping; a timer, for calculating a duration between the first trigger signal and the second trigger signal, and recording the duration as a drop time; a logic operation processor, having a built-in height calculation formula, for calculating a drop height according to the drop time; and a memory unit, for storing the drop time and the drop height. An electronic device using the magnetic storage device is also presented, which is capable of record the actual drop height when a drop event occurs on the electronic device.12-22-2011
20130188274COMMUNICATION PATH LATENCY MEASUREMENT USING CAPACITIVE COUPLING - Systems and/or methods for measuring latency in an electronic device such as, e.g., a storage device, may include coupling circuitry configured to capacitively couple an outbound or write data path to an inbound or read data path. A latency measurement signal may be driven on the write data path, the coupling circuitry may transmit at least a portion of the latency measurement signal from the write data path to the read data path, and the latency measurement signal may be sensed on the read data path to be used to determine communication path latency in the device.07-25-2013
20130188275MAGNETIC HEAD AND DISK DRIVE WITH THE SAME - According to one embodiment, a magnetic head includes a main pole, a write shield pole on a trailing side of the main pole, a recording coil, and a temperature control element unit. The temperature control element unit includes a first electrode on a leading side of the main pole and on both sides of a track of the main pole, a second electrode on the leading side of the main pole and on a track center of the main pole, an N-type semiconductor and a P-type semiconductor connected to the first and second electrodes, and a wiring portion which applies a current via the second electrode, N-type semiconductor, first electrode, P-type semiconductor, and second electrode. The first and second electrodes form a heat absorbing portion and a heat radiating portion.07-25-2013
20130188276DISK DRIVE AND METHOD FOR ARRANGING AND MANAGING CALIBRATION AREA IN DISK DRIVE - According to one embodiment, there is provided a disk drive. In the disk drive, a calibration module calibrates a write condition using a first area in a sequential access area on a disk to which data is to be written next time as a calibration area if the calibration is required. A manager enters the calibration area in a management table in association with a physical address of the first area used as the calibration area. A sequential write module continues a sequential writing from a second area following the first area based on skipping the first area.07-25-2013
20130188277PIEZOELETRIC DEVICE DRIVE METHOD, PIEZOELECTRIC DEVICE DRIVE APPARATUS, AND MAGNETIC DISK DEVICE - According to one embodiment, a piezoelectric device drive method includes measuring gains including a first gain by applying voltages including a first voltage to a piezoelectric device at a first timing, calculating gain characteristics associated with the applied voltages from the measured gains, measuring a second gain by applying the first voltage to the piezoelectric device at a second timing, correcting the calculated gain characteristics based on the first gain and the second gain, and calculating a third gain based on the corrected gain characteristics and the second gain in a case where a second voltage other than the first voltage is applied.07-25-2013
20130188278METHOD OF MANUFACTURING MAGNETIC RECORDING MEDIUM, AND MAGNETIC RECORDING AND REPRODUCING DEVICE - A method of manufacturing a magnetic recording medium is provided. The method includes: forming a magnetic layer 07-25-2013
20120019955HARD DISK DRIVE, METHOD FOR ESTIMATING BACK ELECTROMOTIVE FORCE, AND METHOD FOR CONTROLLING VELOCITY OF HEAD - According to one embodiment, a hard disk drive includes a head, a voice coil motor, a driving circuit, an identification unit, a storage unit, and an estimation unit. The head is configured to perform write/read of information to a storage medium. The voice coil motor is configured to move the head. The driving circuit is configured to drive the voice coil motor, based on a command signal. The identification unit is configured to identify at least one parameter of a discrete-time model. The discrete-time model represents a transfer function from the command signal to a voltage drop quantity by an inductance of a coil of the voice coil motor. The storage unit is configured to store the parameter. The estimation unit is configured to estimate a back electromotive force of the coil, based on the discrete-time model including the parameter.01-26-2012
20120019954METHOD AND APPARATUS FOR BIPOLAR SERVO MARKS WRITING WITH HIGH OUTPUT - A method and apparatus for bipolar servo marks writing with high output. The method includes providing a servo write head having first and second write gaps; and applying a varying current comprising either (i) abrupt changes in current in combination with current ramps or (ii) patterns of high-frequency current pulses before and after writing servo marks to a medium proximate to and moving past the first and second write gaps. The apparatus includes a bipolar servo write driver configured to generate a varying bipolar current signal having both negative and positive polarity currents and a servo write head having a first write gap and second write gap spaced apart, the varying current signal comprising either (i) abrupt changes in current in combination with current ramps or (ii) patterns of high-frequency current pulses before and after low-frequency pulses and a component to move a medium proximate to and past the first and second write gaps.01-26-2012
20130194698POWER CONVERTER, CONTROL METHOD OF POWER CONVERTER, AND HARD DISK DRIVE - A power converter includes a first inductor, a rectifier arm, a first switch arm including a first and second switch circuits, a second switch arm including a third switch circuit and a first capacitor, a LC serial circuit, a Transformer, a rectification and smoothing circuit connected to secondary winding of the transformer, and a control circuit to perform on-off control of the three switch circuits. The rectifier arm, the first and second switch arms and the LC serial circuit are connected in parallel with each other. The LC serial circuit and primary winding of the transformer are connected. AC power supply is connected to the rectifier arm via the first inductor. The control circuit includes an output voltage control circuit to control output voltage at specific setting value, an intermediate voltage control circuit to control intermediate voltage at specific setting value, and a power factor correction control circuit.08-01-2013
20130194697MAGNETIC DISK DEVICE AND DISTURBANCE COMPENSATION METHOD FOR DUAL-STAGE ACTUATOR - A magnetic disk device according to one embodiment includes: a disturbance vibration detector; a movement position controller; and a disturbance compensation module. The disturbance vibration detector detects a disturbance vibration component with respect to a fine-movement actuator. The movement position controller drives each of the fine-movement actuator and a coarse-movement actuator to control a movement position of a magnetic head. The disturbance compensation module corrects the movement position so as to suppress the disturbance vibration component detected by the disturbance vibration detector.08-01-2013
20130194696DISK DRIVE AND WRITE CONTROL METHOD - According to one embodiment, a disk drive writes, upon receiving a first write data block in a plurality of write data blocks having continuous logical block addresses, the first write data block in a first storage location which is included in a specific area on a disk and is adjacent to a position of the head, and writes a second write data block in a second storage location which is included in the specific area and is adjacent to the position of the head. The second storage location is a storage location skipped from the first storage location by an interval corresponding to a difference between a write completion timing of the first write data block and a reception timing of the second write data block.08-01-2013
20130194695MAGNETIC DISK DEVICE AND METHOD OF CONTROLLING HEAD POSITION - According to one embodiment, a magnetic disk device includes a reference head select module selects any one of magnetic heads as a reference head; a follow-up controller executes a follow-up control of a trajectory of the reference head based on a signal read by the reference head; and an eccentric controller executes an eccentric control of a trajectory of a magnetic head other than the reference head in order that an eccentric error between the trajectory of the reference head and the trajectory of the corresponding magnetic head is close to zero.08-01-2013
20130194694SPINDLE MOTOR - There is provided a spindle motor including: a sleeve provided with a shaft protruded in an upward axial direction and having oil filling a bearing clearance formed between the sleeve and the shaft, the sleeve rotatably supporting the shaft; a base member including a mounting part protruded in the upward axial direction, the mounting part having the sleeve fixed to an inner surface thereof; and a hub fixed to an upper portion of the shaft and including a main wall part, the main wall part being formed with at least a portion of an inner surface thereof corresponding to an outer surface of the sleeve and being formed with at least a portion of an outer surface thereof corresponding to the inner surface of the mounting part, the main wall part and the mounting part having an interval therebetween widening in the downward axial direction.08-01-2013
20130194693MAGNETIC MEDIA AND MAGNETIC RECORDING DEVICES USING FLUORINE COMPOUNDS - According to one embodiment, a lubricant includes a perfluoropolyether having a chemical structure of08-01-2013
20120038999APPARATUS AND METHOD FOR RECEIVING AND POSITIONING A READ/WRITE HEAD TO A DISK FOR TESTING AND METHOD OF REMOVING A TESTED READ/WRITE HEAD FROM A TEST APPARATUS - An apparatus for receiving and positioning a read/write head to a disk and related methods are disclosed. The apparatus includes: a deck; a spindle on the deck; a safety enclosure surrounding at least the spindle; and a movable carriage having at least one head receiving portion. The carriage is movable between a first position wherein the head receiving portion is outside the safety enclosure and a second position wherein the head receiving portion is inside the safety enclosure. The apparatus further includes an automated mechanism arranged to pick up the head from the head receiving portion when in the second position and to load the head to the disk for testing.02-16-2012
20130201579DISK-BASED STORAGE DEVICE WITH HEAD POSITION CONTROL RESPONSIVE TO DETECTED INTER-TRACK INTERFERENCE - A hard disk drive or other disk-based storage device comprises a storage disk, a read/write head configured to read data from and write data to the storage disk, and control circuitry coupled to the read/write head and configured to process data received from and supplied to the read/write head and to control positioning of the read/write head relative to the storage disk. The control circuitry comprises an inter-track interference detector configured to process a signal read from at least a given track of the storage disk via the read/write head in order to detect interference in that signal from at least one other track of the storage disk. The control circuitry further comprises an inter-track interference based head position controller configured to adjust the positioning of the read/write head responsive to the detected interference.08-08-2013
20130201580VIRTUAL TAPE DEVICE AND CLEANING CONTROL METHOD - A virtual tape device includes a first drive group of virtual tape drives, a first determination unit, and a first instruction unit. The first drive group is assigned to a first information processing apparatus. The first determination unit determines, upon receiving a first cleaning instruction for cleaning a first virtual tape drive included in the first drive group from the first information processing apparatus, whether the first cleaning instruction is to be output to a physical tape device connected to the virtual tape device. The first instruction unit instructs, when the first determination unit determines that the first cleaning instruction is to be output to the physical tape device, a first physical tape drive corresponding to the first virtual tape drive to perform cleaning. The first physical tape drive is included in the physical tape device.08-08-2013
20130201577ACTIVELY SYNCHRONIZING MAGNETIC RESPONSES OF A SHIELD AND A WRITE POLE - In an example, a method of manufacturing a transducer head comprises configuring a control circuit to actively synchronize magnetic responses of a shield and a write pole during operation. The method also comprises configuring the control circuit to energize at least one coil wire during operation with a current direction opposite to current flow in a main transducer head coil. In another example, a method comprises actively synchronizing magnetic responses of a shield and a write pole. In another example, a transducer head comprises a write pole and a shield, and a control circuit actively synchronizes magnetic responses of the shield and the write pole.08-08-2013
20130201578REFERENCE VOLTAGE CIRCUIT FOR ADAPTIVE POWER SUPPLY - Interface circuitry of a storage device or other type of processing device comprises at least one data path, and an adaptive power supply configured to provide a variable supply voltage to the data path. The adaptive power supply comprises a reference voltage circuit having a plurality of field effect transistors collectively configured to provide a variable reference voltage, with different ones of the field effect transistors being biased into different operating regions. For example, a first subset of the field effect transistors may each be biased into a linear region such that the variable reference voltage tracks variations in on-resistance of one or more corresponding field effect transistors of the data path, and a second subset of the field effect transistors may each be biased into a saturation region such that the variable reference voltage tracks variations in threshold voltage of the corresponding field effect transistors of the data path.08-08-2013
20120300339MAGNETIC RECORDING MEDIUM AND METHOD OF MANUFACTURING THE SAME, AND MAGNETIC RECORD/REPRODUCTION APPARATUS - According to the present invention, a magnetic recording medium is provided including a disk-shaped non-magnetic substrate and at least a perpendicular magnetic layer formed on the disk-shaped non-magnetic substrate, wherein the perpendicular magnetic layer has a structure in which an FePt or CoPt nanoparticle array is formed on a formation surface, on which a plurality of striations each having a circumferential directional component are formed, by a texturing treatment; a manufacturing method thereof; and a magnetic record/reproduction apparatus including the magnetic recording medium or a magnetic recording medium manufactured according to the manufacturing method.11-29-2012
20120075742MAGNETIC DISK DEVICE, ELECTRONIC APPARATUS AND, HEAD CONTROL METHOD - A magnetic disk device includes a head, a coil motor, a drive circuit, a voltage detector, a head position calculation unit, a velocity calculation unit, a counter electromotive voltage calculation unit, a coil resistance estimation unit, and a control unit. The head position calculation unit calculates a position of the head for each sampling cycle on the basis of servo information. The velocity calculation unit calculates a velocity of the head for each sampling cycle. The counter electromotive voltage calculation unit calculates a counter electromotive voltage of the coil for each sampling cycle. The coil resistance estimation unit successively estimates a coil resistance value of the coil. The control unit calculates a drive instruction for controlling the velocity and outputs the drive instruction to the drive circuit. In addition, the counter electromotive voltage calculation unit subtracts a voltage drop from the inter-terminal voltage to calculate the counter electromotive voltage.03-29-2012
20130094106LOW TRANSLATIONAL LOAD SUSPENSION ASSEMBLY - Implementations described and claimed herein address the foregoing problems by providing a suspension assembly used in a storage device to support a transducer head, wherein the suspension assembly comprises a base plate for attaching to an actuator arm and a moving portion movably attached to the base plate. The base plate is fixed and/or clamped to the actuator arm and the moving portion adapted to rotate about a center of rotation. The moving portion is adapted to have a center of mass of its moving mass substantially close to its center of rotation. In one implementation, a counter-weight is attached to the moving portion to move the center of mass of its moving mass substantially close to its center of rotation to minimize inertial loads to the system during suspension actuation.04-18-2013

Patent applications in class Controlling the head

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