Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: According to one embodiment, a suspension assembly includes a support plate, a trace member on the support plate and a drive element mounted on the trace member. The trace member includes a metal plate, and a multilayered member on the metal plate. The multilayered member includes a first insulating layer, a conductive layer stacked on the first insulating layer, a second insulating layer stacked on the conductive layer. The multilayered member includes a mount portion on which the drive element is mounted, and a branching portion arranged along the mount portion with a gap therebetween. At least one portion of the branching portion is formed into a thin portion having a thickness less than other portions of the multilayered member.

Abstract: According to one embodiment, a magnetic head is arranged opposite a magnetic recording medium including a recording layer. The magnetic head includes a magnetic pole, a light emitting unit, and a distance adjusting unit. The magnetic pole includes a soft magnetic material. The light emitting unit is arranged with respect to the magnetic pole in a travel direction of the magnetic head, and emits light with respect to the recording layer. The distance adjusting unit adjusts a distance between the magnetic pole and the light emitting unit.

Abstract: 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.

Abstract: 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.

Abstract: According to one embodiment, a magnetic head is arranged opposite a magnetic recording medium including a recording layer. The magnetic head includes a magnetic pole, a light emitting unit, and a distance adjusting unit. The magnetic pole includes a soft magnetic material. The light emitting unit is arranged with respect to the magnetic pole in a travel direction of the magnetic head, and emits light with respect to the recording layer. The distance adjusting unit adjusts a distance between the magnetic pole and the light emitting unit.

Abstract: 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 ?-axis voltage component adder and a ?-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 ?-axis current component adder and a ?-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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: According to one embodiment, a suspension assembly includes a support plate, a trace member attached to the support plate, and an actuation element configured to expand and contract, and fixed to the trace member. The trace member includes a proximal-end plate portion, a metallic plate including a division plate portion, an insulating layer including a bridge portion, a conductive layer to form a plurality of traces and a counter-plate provided on the bridge portion between the proximal-end plate portion and the division plate portion and opposing the actuation element via the insulating layer, and the actuation element is located on the bridge portion.

Abstract: According to one embodiment, a suspension assembly includes a support plate including a distal end portion, a trace member attached to the support plate, an elastic supporting member made from a distal end portion of the trace member and configured to support a head, and an actuation element expandable/contractible in the longitudinal direction of the trace member, at least a part of a bottom of which is adhered to a seating surface formed from a cover insulating layer of the trace member.

Abstract: 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.

Abstract: 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 I becomes zero in a state in which all the switching devices are turned off (S11 to S13). Every time the motor current I becomes zero, the abnormal-time motor control section sets an ON time T0 corresponding to steering torque |tr| (S14 to S15), and turns on the switching devices corresponding to the direction of the steering torque for the ON time T0 (S17 to S20). With this operation, an average current Iavg corresponding to the steering torque |tr| flows through the motor 20, whereby deterioration of the followability of steering assist is suppressed.

Abstract: 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.

Abstract: 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.

Abstract: 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.