Koyo Seiko Company, Ltd.

Jtekt Corporation

Gates Unitta Asia Company

Kensaku Nakamura

Takehiro Saruwatari

Kazuaki Nagamatsu

Akihiro Hironaka

Hiroshi Murataka

Atsuya Miyata

Tetsuya Murakami

Kunihiro Oka

Hiroto Sasaki

Kousuke Yamanaka

Osamu Sano

Masahide Nakamura

Masato Mizuhara

Hiroki Yamahana

Nicolas Plataret

A rack shaft supporting device includes a support yoke, a plug, an intermediate component, a torque generation spring, and rolling elements. The plug has a plug end portion and plug cam faces formed in the plug end portion. The intermediate component is arranged between the plug and the support yoke in a state where the intermediate component is rotatable relative to the rack housing and movable relative to the rack housing in a pushing direction. The intermediate component has an intermediate opposed portion opposed to the plug end portion and intermediate cam faces opposed to the plug cam faces. The rolling elements are arranged between the plug cam faces and the intermediate cam faces, and make contact with each of the plug cam faces and the intermediate cam faces.

Rack shaft supporting device and steering system including the same

An electric power steering apparatus includes a transmission mechanism for transmitting an output from an electric motor for steering assist to a steering mechanism. The transmission mechanism includes a driving gear, an intermediate gear and a driven gear. An eccentric mechanism for eccentrically locating the intermediate gear is provided in order that a center axis of the intermediate gear is moved toward at least one of the axes of the driving gear and the driven gear while maintaining a parallel relation. The eccentric mechanism includes an intermediate-gear support shaft having a center axis. The intermediate-gear support shaft is supported by first and second circle holes in a manner to be rotatable about the center axis thereof for adjustment of a rotational position thereof, the first and second circle holes have their center axes aligned coaxially with each other. The intermediate gear is rotatably supported by an eccentric portion provided at an outer periphery of the intermediate-gear support shaft. The eccentric portion includes a cylindrical surface eccentric relative to the center axis of the intermediate-gear support shaft.

Electric power steering apparatus

An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other, and a belt tension adjuster.

An electric power steering apparatus includes a speed reducing mechanism for decelerating the rotation of a rotatable shaft in an electric motor and a converting mechanism for converting the output rotation of the speed reducing mechanism into the axial movement of a steering shaft extending toward the right and left sides of a vehicle. The speed reducing mechanism includes an input pulley driven by the electric motor, an output pulley arranged with the steering shaft enclosed thereby, a belt for connecting the input pulley and the output pulley to each other and a belt tension adjuster.

A nut member which is rotated by power transmission from a motor in a rack housing is supported by a thrust bearing fitted and fixed in a first housing having an integrally formed fixing section for fastening to a vehicle body so that the nut member cannot move in both directions along an axial direction. Thrust loads applied in both directions to the nut member with the conversion of rotation into movement of a steering shaft in an axial direction are carried by the first housing through the thrust bearing. The structure of the connection section of the first housing and second housing is simplified, and the housing is fixed in a stable manner to prevent deterioration in steering feeling.

Steering apparatus for vehicle

An electric power steering apparatus comprises a rack shaft movable in the axial direction. The rack shaft is meshed with a pinion rotated in response to the operation of a steering member. The rotation of the output shaft in an electric motor is decelerated by first and second gears which are meshed with each other. A motion conversion mechanism for converting the rotation of the second gear into the axial movement of the rack shaft comprises a rotating cylinder rotated in synchronization with the second gear and a screw shaft. The screw shaft is integrally provided coaxially with the rack shaft and is screwed into the rotating cylinder through a rolling member. A screw groove in the screw shaft and the teeth in the first gear are twisted in the same direction.

An electric power steering apparatus comprises a speed reduction mechanism for decelerating the rotation of an output shaft in an electric motor for steering assist. The speed reduction mechanism comprises a driving gear connected to the output shaft in the electric motor and a driven gear meshed with the driving gear. One of respective tooth sections in the driving gear and the driven gear includes a tooth section formed of a material having a relatively low hardness, and the other tooth section includes a tooth section formed of a material having a relatively high hardness. The profile of the tooth section formed of the material having a relatively low hardness is shifted in the direction in which the thickness at the root of the teeth of the tooth section is increased. The profile of the tooth section formed of the material having a relatively high hardness is shifted in the direction in which the thickness at the root of the teeth of the tooth section is decreased.

A power steering apparatus comprises a rotary cylinder supported with its movement in the axial direction restrained and rotated coaxially with the steering shaft by the force a transmitted from the motor for assisting steering, a plurality of feed rings held eccentrically in said rotary cylinder with their axial centers in parallel, and an engaging groove formed spirally around the outer circumference of the steering shaft for engaging with the projections provided circumferentially on the inner surfaces of the respective feed rings. With this arrangement, it becomes possible to convert the rotation of the motor into the movement in the axial direction of the steering shaft. Thus, this power steering apparatus has a low noise power transmission mechanism with a simple structure.

Growing community of inventors

Kashiba, Japan

Kensaku Nakamura