Patent application number | Description | Published |
20110094821 | ELECTRICAL POWER SUPPLY UNIT FOR VEHICLE - An electrical power supply unit for vehicle comprises: a Main Power Supply | 04-28-2011 |
20130013154 | ELECTRIC POWER STEERING SYSTEM - A feedforward control section computes, on the basis of a target current absolute value, a voltage limit value of a motor drive circuit, and a rotational speed ωr of a motor, a phase angle of a voltage vector which represents the output voltage of the motor drive circuit by a d-q coordinate system, the phase angle being a phase angle in relation to the d-axis of the d-q coordinate system. A feedback control section computes a phase angle based on a deviation between the target current absolute value and the actual current absolute value. A PWM control signal generation section outputs PWM control signals such that the motor drive circuit outputs a three-phase drive voltage whose electrical angle is advanced by a phase angle. Thus, in the case where a large reverse input is applied to a steering mechanism, the motor is caused to generate a large torque to thereby prevent the steering wheel from being rotated. | 01-10-2013 |
20130145865 | TORQUE DETECTION APPARATUS - A first excitation AC signal (V | 06-13-2013 |
20130261886 | TORQUE DETECTION DEVICE - An output section of one detection coil of a first resolver and an output section of one detection coil of a second resolver are connected by a first inter-coil resistor element, and an output section of the other detection coil of the first resolver and an output section of the other detection coil of the second resolver are connected by a second inter-coil resistor element. A sin wave signal for excitation is supplied to one of first and second excitation coils, and a cos wave signal for excitation having the same frequency as that of the sin wave signal for excitation and having a phase delay of 90° in relation to the sin wave signal for excitation is supplied to the other of the first and second excitation coils. By virtue of this configuration, the rotational angles of the two resolvers can be calculated even when one of detection lines is broken. | 10-03-2013 |
20130320893 | ELECTRIC POWER STEERING APPARATUS - When a current sensor fails, instead of a normal-time motor control section, an abnormal-time motor control section drives and controls a motor. The abnormal-time motor control section detects a timing at which motor current becomes zero in a state in which all the switching devices are turned off. Every time the motor current becomes zero, the abnormal-time motor control section sets an ON time corresponding to steering torque, and turns on the switching devices corresponding to the direction of the steering torque for the ON time. With this operation, an average current corresponding to the steering torque flows through the motor, whereby deterioration of the followability of steering assist is suppressed. | 12-05-2013 |
20140005894 | ELECTRIC POWER STEERING APPARATUS | 01-02-2014 |
20140139158 | MOTOR CONTROL DEVICE AND STEERING DEVICE FOR VEHICLE - In a state in which the energization in the first direction is possible between the motor and the drive circuit and the motor is not rotating at high speed, when the phase induced voltage value of the specific phase that is the target of determination is continuously equal to or smaller than the abnormality determination threshold, the abnormality detecting unit determines that an open malfunction has occurred in the relay FET of the specific phase. | 05-22-2014 |
20140207335 | ELECTRIC POWER STEERING SYSTEM - There is provided a drive control method for a motor including multiple sets of coils and drive circuits in an electric power steering system. In order to reduce computational load when sensorless control is executed, an electrical angle estimator includes an α-axis voltage component adder and a β-axis voltage component adder that add together voltage vectors of a first coil and a second coil expressed in a two-phase fixed coordinate system, an α-axis current component adder and a β-axis current component adder that add together current vectors of the first coil and the second coil expressed in a two-phase fixed coordinate system, and an induced voltage computing unit that computes an induced voltage based on an added voltage vector and an added current vector. | 07-24-2014 |
20140336878 | ROTATIONAL-ANGLE DETECTION DEVICE AND ELECTRIC POWER-STEERING DEVICE PROVIDED WITH ROTATIONAL-ANGLE DETECTION DEVICE - When a shaft misalignment detection part detects occurrence of a shaft misalignment that is a misalignment in a relative position in a radial direction of a rotary shaft between a magnet part and a sensor part, the shaft misalignment detection part outputs a shaft misalignment determination flag to a correction part and a control change instruction part. The correction part calculates a motor rotational angle so as to reduce a detection error caused by the shaft misalignment. The control change instruction part outputs instructions of changing calculation methods so that influence by the detection error decreases to an assist torque setting part and an assist current instruction part. | 11-13-2014 |
20150298726 | STEERING CONTROL SYSTEM FOR VEHICLE AND STEERING CONTROL METHOD FOR VEHICLE - A steering control system for a vehicle includes an electric motor, a torque sensor, an angular velocity sensor, and a control unit. The electric motor applies assist force to a turning operation of a steering wheel. The torque sensor detects a torque generated in a steering system including the steering wheel and varying with the turning operation. The angular velocity sensor detects an angular velocity generated in the steering system and varying with the turning operation. The control unit computes an assist control amount for the turning operation by using the torque and the angular velocity, and, when an abnormality occurs in a torque detection operation, increases a control amount computed by using the angular velocity among control amounts that constitute the assist control amount as compared to that when torque sensor operation is normal and executes drive control over the electric motor based on the assist control amount. | 10-22-2015 |
20150314804 | ELECTRIC POWER STEERING DEVICE FOR VEHICLE - An electric power steering device for a vehicle includes a plurality of assist systems electromagnetically driving an electric motor. When a first or second assist system malfunctions, a malfunction state assist amount calculation part calculates an assist amount while decreasing a limit value at the vehicle stopping, to an amount smaller than a limit value at the vehicle moving. When a malfunction such as a disconnection or a fixing of the switching elements occurs in the first or second assist systems on the basis of a judgment result of a malfunction judgment function, an assist amount switching part supplies an assist amount received from the malfunction state assist amount calculation part to first and second motor drive control parts. When a malfunction occurs in one of the first and second assist systems, one of the first and second motor drive control parts drives the motor by using the assist amount. | 11-05-2015 |
Patent application number | Description | Published |
20100246047 | MAGNETIC HEAD AND INFORMATION STORAGE DEVICE - According to one embodiment, a magnetic head includes a magnetic pole layer including a magnetic pole extending along a layer, a coil layer configured to adjoin the magnetic pole layer and including a plurality of conductor patterns constituting a part of a coil wound around the magnetic pole and a resin which fills up a gap between the conductor patterns, a heater layer configured to adjoin the coil layer and including a heater extending in the heater layer via an area along a coil-forming region in which the conductor patterns in the coil layer are formed and an area along a no-coil region off the coil-forming region, and a transition-reluctant portion in that part of the no-coil region which adjoins the heater and having a glass transition temperature higher than that of the resin or not having any glass transition temperature. | 09-30-2010 |
20100315746 | HEAD GIMBAL ASSEMBLY AND FIXING METHOD OF BASE PLATE AND CARRIAGE ARM - According to one embodiment, a head gimbal assembly includes: base plate body; flexure; through hole passing through the base plate body; cylindrical base that upstands from the front surface of the base plate body, and has a first inner diameter; a cylindrical flange that continues to the base around the through hole and has a second inner diameter smaller than the first inner diameter; and inner wall surface that is defined by the flange and extends along a cylindrical surface formed by a generating line parallel to a central axis of the through hole. A ratio of a thickness T of the flange defined along a virtual plane orthogonal to the central axis of the through hole to a length L of the inner wall surface defined in a direction parallel to the central axis of the through hole is set to 1.5 or less. | 12-16-2010 |
20120002328 | HEAD STACK ASSEMBLY AND DISK DRIVE WITH THE SAME - According to an embodiment, a head stack assembly includes an arm including a swaged seat surface with swaged hole, a load beam supporting a head, and a baseplate secured to a proximal end portion of the load beam, including an annular protrusion secured to the swaged hole of the arm by swaging, and secured to the swaged seat surface. The arm includes a distal end portion located on a longitudinal end side of the arm with respect to the center of the swaged hole and being less rigid than the other portion of the arm around the swaged hole. | 01-05-2012 |
Patent application number | Description | Published |
20090103208 | MAGNETIC HEAD - According to an aspect of an embodiment, a magnetic head includes: a write element including a first magnetic pole and a second magnetic pole magnetically connected to the first magnetic pole; and a nonmagnetic insulating layer made of inorganic material surrounding the write element. The magnetic head further includes: upper and lower low-thermal-expansion material layers disposed on and under the nonmagnetic insulating layer, respectively, the low-thermal-expansion material layers having a thermal coefficient lower than that of the nonmagnetic insulating layer; and a heater element embedded in the nonmagnetic insulating layer. | 04-23-2009 |
20090310243 | MAGNETIC HEAD AND MAGNETIC STORAGE DEVICE - A magnetic head that floats up while directing an air bearing surface to a relatively moving storage medium and stores information into the storage medium, the magnetic head includes: a main magnetic pole that generates a magnetic field for recording information into the storage medium; and a heater that adjusts a floating-up amount of the magnetic head from the storage medium by deforming the air bearing surface with heat, wherein the heater has a shape that extends towards the air bearing surface up to a proximate distance at which a distance from the air bearing surface overlaps with the main magnetic pole while monotonously decreasing the distance from the air bearing surface to pass a proximate point to the main magnetic pole, and that extends away from the air bearing surface while monotonously increasing the distance from the air bearing surface after passing the proximate point. | 12-17-2009 |
20090316302 | MAGNETIC HEAD AND MAGNETIC DISK UNIT - A magnetic head includes: a slider which floats above a recording medium by air flow generated by rotation of the recording medium; and an element forming section fixed to an air outflow side of the slider and formed with an element which accesses the recording medium. The element forming section includes: a recording element having a main magnetic pole which records data in the recording medium; and a reproducing element which is formed closer to the slider than the recording element and which reproduces data recorded in the recording medium. The element forming section further includes: a heat insulation layer formed between the main magnetic pole and the reproducing element; and a heater formed closer to the slider than the heat insulation layer. | 12-24-2009 |
20100073815 | MAGNETIC HEAD AND MAGNETIC DISK DEVICE - A magnetic head provided on a drain end side of a head substrate constituting a head slider includes a heater, a write coil, a shield, an insulation layer between the heater and the head substrate, a thermal insulation layer whose thermal conductivity is lower than the insulation layer and a thermal radiation layer whose thermal conductivity is higher than the shield, wherein the thermal insulation layer is disposed between the heater and the head substrate and the thermal radiation layer is disposed between the write coil and the head substrate. | 03-25-2010 |
20100118439 | MAGNETIC HEAD AND INFORMATION STORAGE APPARATUS - According to one embodiment, a magnetic head includes: a coil configured to be supplied with current; a main magnetic pole configured to be disposed along one surface of the coil and extend in a direction orthogonal to a floating surface from the floating surface; at least one auxiliary magnetic pole configured to be disposed along other surface of the coil and parallel to the main magnetic pole; a connecting portion configured to be linked with the coil and connect the main magnetic pole and the auxiliary magnetic pole; and a radiating layer configured to be disposed between the coil and the auxiliary magnetic pole and have larger thermal conductivity than the auxiliary magnetic pole. | 05-13-2010 |
Patent application number | Description | Published |
20150110551 | STRUCTURAL BODY FOR SHAFT, MALE MEMBER, AND FEMALE MEMBER - A shaft structure installed in a shaft capable of making a power-transmission, the shaft structure including: a male component having a plurality of male splines formed on an outer peripheral part thereof; and a female component having a plurality of female splines formed on an inner peripheral part thereof, the inner peripheral part configured to allow the outer peripheral part of the male component to be engaged therein so that the male component and the female component can be slidably fitted with respect to each other in an axial direction thereby making up said shaft structure, wherein the outer peripheral part of the male component and the inner peripheral part of the female component have a fabric impregnated with rubber or resin interposed therebetween. | 04-23-2015 |
20150114156 | BALL SCREW, SEAL MATERIAL, AND SEAL STRUCTURE - A ball screw including: a male component having male grooves on an outer periphery for a ball to roll; a female component fitted together with the male component in an axial direction having female grooves facing the male grooves on an inner periphery for the ball to roll and a circulation path for the ball to circulate; and a seal member at one end, at the other end, or at each of one and the other ends of the female component in the axial direction and including a hole capable of communicating with the inner periphery, a fiber layer having a fitting surface having a convex part capable of being fitted in the male grooves when the male component is inserted into the hole and a surface made of fibers impregnated with rubber or resin, and a rubber or resin layer laminated on a surface opposite to the fitting surface. | 04-30-2015 |
20150275946 | STRUCTURE FOR SHAFT, MALE MEMBER, AND FEMALE MEMBER - A shaft structure including: a male component having male spline parts and male spline bottom parts on an outer peripheral part; a female component having female spline parts and female spline bottom parts on an inner peripheral part configured to allow the male component to be slidably inserted in an axial direction; and an elastic member arranged on the male component covering a surface of the outer peripheral part of the male component, wherein, in an initial state where the male component is inserted into the female component, the female and male components have first gaps between: sides of the female spline parts; and sides-facing portions of the elastic member, and when the male component is rotated, a time from the initial state to a state where the sides of the female spline parts abut on the portions of the elastic member, has predetermined time differences along the axial direction. | 10-01-2015 |
20160102748 | RACK AND RACK MANUFACTURING METHOD - A rack includes a plurality of thin plates laminated with each other, wherein each of the plurality of thin plates is formed with a set of rack teeth, and adjacent thin plates, which are laminated adjacently to each other, of the plurality of thin plates are fixed together such that respective rack-tooth positions of the adjacent thin plates are displaced from each other in axial directions of adjacent sets of rack teeth. | 04-14-2016 |