Patent application number | Description | Published |
20080247079 | Disk 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 |
20080273262 | Magnetic disk drive, preamplifier for magnetic disk drive, flexible printed cable assembly for magnetic disk drive - Embodiments of the present invention help to improve the cost, mountability, and reliability of a magnetic disk drive that regulates a fly height of a magnetic head slider correspondingly to the operating altitude of the drive by using an air pressure sensor and a heater. According to one embodiment, a preamplifier is a semiconductor chip formed by three-dimensionally laminating thin film circuits on a bulk silicon wafer. An air pressure sensor is integrally formed on the semiconductor chip through a semiconductor process. The air pressure sensor is configured to include an isolating cavity, a diaphragm that deflecting in response to a change in a pressure difference between the isolating cavity and the outside, and lower and upper electrodes and for detecting variation in electrostatic capacitance. The preamplifier including the air pressure sensor integrally formed therein is attached to a flexible printed cable (FPC) to oppose the FPC. A through-hole is provided in a portion opposite the air pressure sensor of the FPC to introduce air pressure in an operating environment into a diaphragm of the air pressure sensor. | 11-06-2008 |
20090141391 | Disk 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 |
20090201598 | Disc drive device - Embodiments of the present invention precisely measure clearance variation by temperature change using a value in a RW channel. In an embodiment of the present invention, an HDD measures resolution by signals in a RW channel. The measured resolution shows variations depending on temperature according to two factors. One factor is the clearance variation depending on the temperature and the other is the variation in operational property of the RW channel depending on the temperature. The HDD compensates for the temperature variation of the resolution according to the two factors. The HDD uses two kinds of sensed temperature. One corresponds to the temperature inside an enclosure in which head sliders are provided and the other corresponds to the temperature of the chip in which the RW channel is implemented. Sensing the drive temperature and the channel temperature independently achieves precise compensation for the variation in the measured resolution caused by clearance variation and channel property. | 08-13-2009 |
20090262608 | Head slider and disk drive - Embodiments of the present invention provide a technique for projecting both a write element portion in writing and a read element portion in reading, and controlling a projecting distance of each write element and read element. According to one embodiment, a light absorbing member and a thermally expanding member are formed near a read element, and light is irradiated to the light absorbing member, thereby a read element is projected. Alternatively, light absorbing members, which absorb light having different wavelengths from each other, and thermally expanding members are formed near a write element and near the read element respectively, and a wavelength or intensity of light to be irradiated is changed, thereby a projecting distance of each of the write element and the read element is individually optionally controlled. | 10-22-2009 |
20100134915 | MAGNETIC HEAD WITH A HEATING ELEMENT BETWEEN THE READ AND WRITE ELEMENT AND METHOD OF MANUFACTURING THEREOF - According to one embodiment, a magnetic head includes a write element, a read element, and a heating element disposed between the write element and the read element. When power is applied to the heating element, either the read element or the write element projects beyond a plane of an air-bearing surface (ABS) of the magnetic head, and when power is not applied to the heating element, a portion of the ABS of the magnetic head facing a magnetic disk close to the heating element has a concave shape. In another embodiment, when power is applied to the heating element, at least one of a portion of the read element and a portion of the write element approaches a magnetic disk, and when power is not applied to the heating element, a portion of the ABS of the magnetic head facing a magnetic disk close to the heating element has a concave shape. | 06-03-2010 |
20110069408 | DISK DRIVE, HEAD-SLIDER AND METHOD FOR CONTROLLING CLEARANCE OF A READ ELEMENT AND A WRITE ELEMENT IN THE DISK DRIVE - A disk drive. The disk drive includes a disk, a head-slider, a moving mechanism, and a controller. The head-slider includes a read/write element, a first heater element, a contact pad, and a second heater element. The read/write element includes a read element configured to read user data from the disk, and a write element configured to write user data to the disk. The moving mechanism is configured to support and to move the head-slider. The controller is configured to control the second heater element to control contact between the contact pad and the disk, and is configured to control clearance between the read/write element and the disk by using the first heater element with the contact pad in contact with the disk. | 03-24-2011 |
20110080671 | HARD-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 |
20110102933 | DISK 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 |
20110141603 | HEAD/DISK CONTACT DETERMINATION - A disk drive including a sensor element that senses contact between a head slider and a disk, a head integrated circuit (IC) comprising an amplification circuit section that amplifies a signal of the head slider, a controller IC comprising a controller that accesses a register of the head IC for controlling the head IC, and an identification section, within the head IC, that determines a contact frequency of the contact by the sensor element by using a timing control signal of the controller IC. | 06-16-2011 |
20110149430 | Magnetic 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 |
20120099218 | MAGNETIC-RECORDING HEAD WITH FIRST THERMAL FLY-HEIGHT CONTROL ELEMENT AND EMBEDDED CONTACT SENSOR ELEMENT CONFIGURABLE AS SECOND THERMAL FLY-HEIGHT CONTROL ELEMENT - A magnetic-recording head with a first thermal fly-height control (TFC) element and an embedded contact sensor element (ECSE) configurable as a second TFC element. The magnetic-recording head includes a write element, a read element, a first heater element, and an ECSE. The write element is configured for writing data to a magnetic-recording disk. The read element is configured for reading data from the magnetic-recording disk. The first heater element is configured as a first TFC element to coarsely adjust a fly-height of the magnetic-recording head with respect to the magnetic recording disk. The ECSE is configured to detect a contact with the magnetic-recording disk, and to function as a second heater element that is configured as a second TFC element to finely adjust the fly-height. The first heater element is configured with a first stroke-length larger than a second stroke-length of the second heater element for adjusting the fly-height. | 04-26-2012 |
20120120521 | CONTACT 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 |