Abstract: An electric power steering apparatus according to the present invention has a biasing member arranged to bias a rack retainer toward a rack bar, wherein a biasing force of the biasing member is set such that, in a two-axis coordinate system with a rotation amount of a steering wheel on a horizontal axis and a steering torque on a vertical axis, the steering torque increases with increase in the rotation amount of the steering wheel in a region before the start of relative movement of the rack bar and the rack retainer.

Abstract: An electric power steering apparatus according to the present invention has a biasing member arranged to bias a rack retainer toward a rack bar, wherein a biasing force of the biasing member is set such that, in a two-axis coordinate system with a rotation amount of a steering wheel on a horizontal axis and a steering torque on a vertical axis, the steering torque increases with increase in the rotation amount of the steering wheel in a region before the start of relative movement of the rack bar and the rack retainer.

Abstract: A steering apparatus includes: a pinion shaft coupled to a steering wheel and having a pinion; a rack shaft having a rack engaged with the pinion and a shaft back located on opposite side of the rack with an axial center of the rack shaft in between; a rack shaft housing that houses and slidably supports the rack shaft; and a rack shaft supporting mechanism having a pressure applying member that applies a pressure onto the shaft back toward the pinion. The shaft back includes a predetermined region provided across a midpoint of the rack which corresponds to a neutral position of the steering wheel. The predetermined region is a right-to-left steering wheel angle region having a height higher than a height of any other region of the shaft back.

Abstract: A steering device includes: a pinion shaft that has a pinion on an outer circumferential surface thereof; a rack shaft that has a rack that engages with the pinion; a rack housing that has a recess on an inner circumferential surface thereof and accommodates the rack shaft; a rack guide that has a protrusion smaller than a width of the recess in axial directions of the rack shaft, and is disposed inside the recess, the rack guide contacting an outer circumferential surface of the rack shaft and an inner circumferential surface of the rack housing, and guiding the rack shaft along an axis of the rack shaft; and a spacer that contacts one side and the other side of the protrusion in the axial directions of the rack shaft, and is disposed between an inner surface of the recess and an outer surface of the protrusion.

Abstract: A steering device includes: a rack; a pinion; a pinion shaft having the pinion on an outer circumferential surface thereof; a rack shaft having the rack that engages with the pinion; a rack guide that is provided on a side of the rack shaft opposite from the pinion shaft and guides the rack shaft along an axis of the rack shaft; a biasing member that biases the rack guide against the rack shaft to press the rack against the pinion; a guide housing that accommodates the rack guide and the biasing member; and a buffer member provided between an outer circumferential surface of the rack guide and an inner circumferential surface of the guide housing. The buffer member has a cylindrical member and an elastic member. The elastic member is disposed on at least either one of an inner circumferential surface and an outer circumferential surface of the cylindrical member.

Abstract: A steering apparatus includes: a pinion shaft coupled to a steering wheel and having a pinion; a rack shaft having a rack engaged with the pinion and a shaft back located on opposite side of the rack with an axial center of the rack shaft in between; a rack shaft housing that houses and slidably supports the rack shaft; and a rack shaft supporting mechanism having a pressure applying member that applies a pressure onto the shaft back toward the pinion. The shaft back includes a predetermined region provided across a midpoint of the rack which corresponds to a neutral position of the steering wheel. The predetermined region is a right-to-left steering wheel angle region having a height higher than a height of any other region of the shaft back.

Abstract: A steering device includes: a rack; a pinion; a pinion shaft having the pinion on an outer circumferential surface thereof; a rack shaft having the rack that engages with the pinion; a rack guide that is provided on a side of the rack shaft opposite from the pinion shaft and guides the rack shaft along an axis of the rack shaft; a biasing member that biases the rack guide against the rack shaft to press the rack against the pinion; a guide housing that accommodates the rack guide and the biasing member; and a buffer member provided between an outer circumferential surface of the rack guide and an inner circumferential surface of the guide housing. The buffer member has a cylindrical member and an elastic member. The elastic member is disposed on at least either one of an inner circumferential surface and an outer circumferential surface of the cylindrical member.

Abstract: A steering device includes: a pinion shaft that has a pinion on an outer circumferential surface thereof; a rack shaft that has a rack that engages with the pinion; a rack housing that has a recess on an inner circumferential surface thereof and accommodates the rack shaft; a rack guide that has a protrusion smaller than a width of the recess in axial directions of the rack shaft, and is disposed inside the recess, the rack guide contacting an outer circumferential surface of the rack shaft and an inner circumferential surface of the rack housing, and guiding the rack shaft along an axis of the rack shaft; and a spacer that contacts one side and the other side of the protrusion in the axial directions of the rack shaft, and is disposed between an inner surface of the recess and an outer surface of the protrusion.

Abstract: An electric power steering device provided with two belleville springs for suppressing the axial movement of a worm rotated by a steering-assisting electric motor and having shaft portions at its both end portions, and limiting members for limiting the deflection amounts of the two belleville springs. The limiting members are respectively disposed at portions along the outer circumferences of the shaft portions at both end portions of the worm, the respective inner circumferential portions of the two belleville springs are formed into flat portions, the outer circumferential portions thereof are respectively formed into tapered portions having a taper shape, and the limiting members are made contact with the flat portions, thereby limiting the deflection amounts of the tapered portions. Hence, the limiting members can be provided without increasing the size of the worm serving as a small gear.

Abstract: An electric power steering device provided with two belleville springs for suppressing the axial movement of a worm rotated by a steering-assisting electric motor and having shaft portions at its both end portions, and limiting members for limiting the deflection amounts of the two belleville springs. The limiting members are respectively disposed at portions along the outer circumferences of the shaft portions at both end portions of the worm, the respective inner circumferential portions of the two belleville springs are formed into flat portions, the outer circumferential portions thereof are respectively formed into tapered portions having a taper shape, and the limiting members are made contact with the flat portions, thereby limiting the deflection amounts of the tapered portions. Hence, the limiting members can be provided without increasing the size of the worm serving as a small gear.

Abstract: The support body engaged with the interior side of the tooth body provided at the worm wheel of the electric power steering apparatus comprises: a corrugated cylinder part press-formed to have a plurality of concavities on the exterior side thereof and convexities to the interior formed by the concavities which are arranged in a peripheral direction; and a plate part an exterior edge of which is united with an end of the corrugated cylinder part, wherein the tooth body is engaged with the exterior side of the corrugated cylinder part. With the method of manufacturing the gear, synthetic resin of the tooth body can be deposited uniformly on the support body made of metal engaged with the interior of the tooth body, costs can be reduced, and the support body can be engaged with the tooth body without generating voids and weld marks.

Abstract: The support body engaged with the interior side of the tooth body provided at the worm wheel of the electric power steering apparatus comprises: a corrugated cylinder part press-formed to have a plurality of concavities on the exterior side thereof and convexities to the interior formed by said concavities which are arranged in a peripheral direction; and a plate part an exterior edge of which is united with an end of said corrugated cylinder part, wherein the tooth body is engaged with the exterior side of the corrugated cylinder part. With the method of manufacturing the gear, synthetic resin of the tooth body can be deposited uniformly on the support body made of metal engaged with the interior of the tooth body, costs can be reduced, and the support body can be engaged with the tooth body without generating voids and weld marks.

Abstract: The support body engaged with the interior side of the tooth body provided at the worm wheel of the electric power steering apparatus comprises: a corrugates cylinder part-press-formed to have a plurality of concavities on the exterior side thereof and convexities to the interior formed by the concavities which are arranged in a peripheral direction; and a plate part an exterior edge of which is united with an end of the corrugated cylinder part, wherein the tooth body is engaged with the exterior side of the corrugated cylinder part. With the method of manufacturing the gear, synthetic resin of the tooth body can be deposited uniformly on the support body made of metal engaged with the interior of the tooth body, costs can be reduced, and the support body can be engaged with the tooth body without generating voids and weld marks.

Abstract: In an electric power steering device, a driven gear of a deceleration gear mechanism for transmitting rotation of an electric actuator for generating auxiliary steering power has a gear body made of a synthetic resin material. At least the outer periphery of a metal core ring is covered by the gear body. The gear body is molded and integrated with the core ring by injecting synthetic resin material into a mold, in which the core ring is inserted. A plurality of teeth, each of which has faces which run in the direction of the axis of rotation of the driven gear, are formed on the outer periphery of the core ring so as to be arranged at intervals in a circumferential direction. The synthetic resin material that constitutes the gear body is filled in the spaces between the teeth of the core ring.

Abstract: The support body engaged with the interior side of the tooth body provided at the worm wheel of the electric power steering apparatus comprises: a corrugated cylinder part press-formed to have a plurality of concavities on the exterior side thereof and convexities to the interior formed by said concavities which are arranged in a peripheral direction; and a plate part an exterior edge of which is united with an end of said corrugated cylinder part, wherein the tooth body is engaged with the exterior side of the corrugated cylinder part. With the method of manufacturing the gear, synthetic resin of the tooth body can be deposited uniformly on the support body made of metal engaged with the interior of the tooth body, costs can be reduced, and the support body can be engaged with the tooth body without generating voids and weld marks.

Abstract: In an electric power steering device, a driven gear of a deceleration gear mechanism for transmitting rotation of an electric actuator for generating auxiliary steering power has a gear body made of a synthetic resin material. At least the outer periphery of a metal core ring is covered by the gear body. The gear body is molded and integrated with the core ring by injecting synthetic resin material into a mold, in which the core ring is inserted. A plurality of teeth, each of which has faces which run in the direction of the axis of rotation of the driven gear, are formed on the outer periphery of the core ring so as to be arranged at intervals in a circumferential direction. The synthetic resin material that constitutes the gear body is filled in the spaces between the teeth of the core ring.