Abstract: A magnetostrictive torque sensor device which detects a torque applied to a rotary shaft is provided. The magnetostrictive torque sensor device includes a magnetostrictive portion provided on a surface of the rotary shaft, a coil and a cylindrical back-yoke disposed in outer periphery of the coil. The coil includes a bobbin arranged in outer periphery of the magnetostrictive portion, and a wire wound around the bobbin. A slit is provided on the back-yoke.

Abstract: An electric motor having a rotation shaft includes a motor housing into which the electric motor is accommodated, at least one pair of rolling bearings positioned in the motor housing and rotatably supporting both ends of the rotation shaft, and a displacement restriction member provided inside the motor housing and restricting a displacement of the rolling bearing in an axial direction of the rolling bearing. Each rolling bearing includes an inner race, an outer race, and rolling elements rotatably supported between the inner race and the outer race. The inner race is press fitted without any gaps onto an outer peripheral surface of the rotation shaft, and the outer race is press fitted without any gaps into a bearing attachment portion provided inside the motor housing.

Abstract: A vehicle steering device in which steering torque is transmitted from a steering wheel to steered wheels via a rack-and-pinion mechanism. The steering device comprises a rack shaft in which a rack is formed, two rack support parts positioned to both sides of a longitudinal direction of the rack shaft relative to the position of a pinion, and an urging part positioned between the two rack support parts. The two rack support parts are positioned near each other so as to support only a back surface of the region where the rack is formed in the rack shaft which is positioned in a steering neutral position, the back surface being supported so as to be capable of sliding in the longitudinal direction. The urging part urges the rack shaft in at least a direction other than towards the rack.

Abstract: The torque sensor includes a plurality of coil units having a substantially cylindrical shape, the coil units including a plurality of detection coils arranged to face a magnetic characteristic change portion formed on a rotary shaft. The coil units include a first coil unit and a second coil unit, and the first coil unit and the second coil unit are disposed in the axial direction of the shaft. The first coil unit and the second coil unit are fixed in an integrally molded resin. Thereby, there is provided a torque sensor having a high productivity and an easy configuration and a method of manufacturing the torque sensor.

Abstract: An electric power steering apparatus 10 has an electric motor 46 for supplying an auxiliary force to a steering force inputted from a steering wheel 16, and transmits the steering force including the auxiliary force to a steered road-wheel 14 at least partially via a rack-and-pinion mechanism 30, thereby performing steering of a vehicle 12. The rack-and-pinion mechanism 30 includes: a pinion 38 provided at a pinion shaft 28 connected to the steering wheel 16; a rack 40 that is provided over a predetermined width at a rack shaft 32 connected to the steered road-wheel 14, and that is engaged with the pinion 38; and a rack guide 70 for urging the rack shaft 32 toward the pinion 38. A pressure angle ?1 of a tooth root of the rack 40 is set to be greater than a pressure angle ?0 of a tooth tip of the rack 40.

Abstract: An electric power steering device is configured to transmit an auxiliary torque to a steering unit of front wheels, and includes: an operator; an electric motor configured to generate the auxiliary torque in accordance with at least a steering torque generated by input from the operator; the steering unit of front wheels which includes a pinion shaft; and a rotation terminating mechanism which provides a motion terminating end of the operator, the rotation terminating mechanism being disposed between the operator and the pinion shaft.

Abstract: An electric damper which does not transmit unbalance wheel vibration to a vehicle body is provided. A low-pass cutoff frequency setting unit and a high-pass cutoff frequency setting unit respectively set the cutoff frequencies for band-stop filters to a frequency band corresponding to unbalance wheel vibration based on a signal indicating a vehicle speed from a vehicle speed sensor, and a function as a band-stop filter comprising a low-pass filter computation unit, a high-pass filter computation unit and an adder is computed for a displacement rate of the vertical motion of a wheel calculated by a differentiating unit in a damper control unit. A damper control amount computation unit calculates a control amount of controlling an electric motor for a motor-driven damper based on the calculated filtered displacement rate, and outputs a control signal to a motor driving unit through a driving circuit output unit.

Abstract: A rack-and-pinion steering apparatus in which a steering gear box for transmitting an operation of a steering wheel to road wheels includes a pinion operatively connected to the steering wheel, a rack bar which has a rack meshing with the pinion, and which is operatively connected to the road wheels, a housing slidably supporting the rack bar, a cylindrical rack guide slidably fitted into a guide hole formed in the housing, and a spring member causing the rack guide to abut on a rear part of the rack bar opposite to the rack by biasing the rack guide. A reaction force, which the rack guide receives from the rack bar, acts on the rack guide in such a way as to cause a rotational moment of the rack guide about an axis different from an axis of the rack guide.

Abstract: Worm gear mechanism includes a driving worm, a torque delivering worm wheel meshing with the worm, and an auxiliary worm wheel superimposed on the torque delivering worm wheel. The auxiliary worm wheel has a pitch diameter greater than that of the torque delivering worm wheel. The auxiliary worm wheel is biased against the driving worm wheel via a biasing member in the form of a leaf spring.

Abstract: This magnetostrictive torque sensor includes: a shaft made of a magnetized material; a magnetostrictive portion provided on the shaft at a position distanced for a predetermined length from an end of the shaft; a detection coil that is arranged so as to face the magnetostrictive portion, and detects a change in a magnetic characteristic of the magnetostrictive portion; and a plating made of an nonmagnetic material, that is provided on the end of the shaft.

Abstract: A worm gear mechanism includes a worm, a torque-transmitting worm wheel meshing with the worm, and an auxiliary worm wheel disposed concentrically with the torque-transmitting worm wheel. The auxiliary worm wheel has a pitch circle diameter set to be greater than a pitch circle diameter of the torque-transmitting worm wheel and hence meshes with the worm in a meshing phase different from that of the torque-transmitting worm wheel. A screw thread provided on the worm actually meshes with teeth of the torque-transmitting worm wheel along a length defined as an actual meshing length. The screw thread has an effective length reduced to be approximately equal to the actual meshing length.

Abstract: An electric power steering apparatus includes a worm gear mechanism for transmitting the torque generated by an electric motor to a steered road wheel of the vehicle. The worm gear mechanism has a worm gear made of metal and a worm wheel formed of plastic material and meshing with the worm gear. The worm gear has a tooth profile including a dedendum part formed in an involute shape and an addendum part formed in a circular arc shape with a center located on a line of action.

Abstract: The torque sensor includes a plurality of coil units having a substantially cylindrical shape, the coil units including a plurality of detection coils arranged to face a magnetic characteristic change portion formed on a rotary shaft. The coil units include a first coil unit and a second coil unit, and the first coil unit and the second coil unit are disposed in the axial direction of the shaft. The first coil unit and the second coil unit are fixed in an integrally molded resin. Thereby, there is provided a torque sensor having a high productivity and an easy configuration and a method of manufacturing the torque sensor.

Abstract: The torque sensor includes a plurality of coil units having a substantially cylindrical shape, the coil units including a plurality of detection coils arranged to face a magnetic characteristic change portion formed on a rotary shaft. The coil units include a first coil unit and a second coil unit, and the first coil unit and the second coil unit are disposed in the axial direction of the shaft. The first coil unit and the second coil unit are fixed in an integrally molded resin. Thereby, there is provided a torque sensor having a high productivity and an easy configuration and a method of manufacturing the torque sensor.

Abstract: An electric power steering apparatus 10 has an electric motor 46 for supplying an auxiliary force to a steering force inputted from a steering wheel 16, and transmits the steering force including the auxiliary force to a steered road-wheel 14 at least partially via a rack-and-pinion mechanism 30, thereby performing steering of a vehicle 12. The rack-and-pinion mechanism 30 includes: a pinion 38 provided at a pinion shaft 28 connected to the steering wheel 16; a rack 40 that is provided over a predetermined width at a rack shaft 32 connected to the steered road-wheel 14, and that is engaged with the pinion 38; and a rack guide 70 for urging the rack shaft 32 toward the pinion 38. A pressure angle ?1 of a tooth root of the rack 40 is set to be greater than a pressure angle ?0 of a tooth tip of the rack 40.

Abstract: An electric damper which does not transmit unbalance wheel vibration to a vehicle body is provided. A low-pass cutoff frequency setting unit and a high-pass cutoff frequency setting unit respectively set the cutoff frequencies for band-stop filters to a frequency band corresponding to unbalance wheel vibration based on a signal indicating a vehicle speed from a vehicle speed sensor, and a function as a band-stop filter comprising a low-pass filter computation unit, a high-pass filter computation unit and an adder is computed for a displacement rate of the vertical motion of a wheel calculated by a differentiating unit in a damper control unit. A damper control amount computation unit calculates a control amount of controlling an electric motor for a motor-driven damper based on the calculated filtered displacement rate, and outputs a control signal to a motor driving unit through a driving circuit output unit.

Abstract: A magnetostrictive torque sensor device which detects a torque applied to a rotary shaft is provided. The magnetostrictive torque sensor device includes a magnetostrictive portion provided on a surface of the rotary shaft, a coil and a cylindrical back-yoke disposed in outer periphery of the coil. The coil includes a bobbin arranged in outer periphery of the magnetostrictive portion, and a wire wound around the bobbin. A slit is provided on the back-yoke.

Abstract: An electric power steering device is configured to transmit an auxiliary torque to a steering unit of front wheels, and includes: an operator; an electric motor configured to generate the auxiliary torque in accordance with at least a steering torque generated by input from the operator; the steering unit of front wheels which includes a pinion shaft; and a rotation terminating mechanism which provides a motion terminating end of the operator, the rotation terminating mechanism being disposed between the operator and the pinion shaft.

Abstract: A rack-and-pinion steering apparatus in which a steering gear box for transmitting an operation of a steering wheel to road wheels includes a pinion operatively connected to the steering wheel, a rack bar which has a rack meshing with the pinion, and which is operatively connected to the road wheels, a housing slidably supporting the rack bar, a cylindrical rack guide slidably fitted into a guide hole formed in the housing, and a spring member causing the rack guide to abut on a rear part of the rack bar opposite to the rack by biasing the rack guide. A reaction force, which the rack guide receives from the rack bar, acts on the rack guide in such a way as to cause a rotational moment of the rack guide about an axis different from an axis of the rack guide.

Abstract: Worm gear mechanism is provided which includes a worm, a torque-transmitting worm wheel and an auxiliary worm wheel. In order to secure a sufficient face width of the torque-transmitting worm wheel, a pitch diameter of the auxiliary worm wheel is set to be greater than a pitch diameter of the torque-transmitting worm wheel. Thus, undesired backlash can be eliminated by the auxiliary worm wheel meshing with the worm with a different meshing phase from the torque-transmitting worm wheel.