Jtekt Corporation

Koyo Seiko Company, Ltd.

Ogino Kogyo Co., Ltd.

Koyo Seiko., Ltd.

Yoshikazu Kuroumaru

Katsutoshi Nishizaki

Shirou Nakano

Ken Matsubara

Shigeki Nagase

Masahiko Sakamaki

Takeshi Ueda

Toshiaki Oya

Noboru Minamoto

Satoshi Motoyama

Masahide Nitano

Takayasu Yamazaki

Yasuhiro Saitou

Yasuhiro Kamatani

Makoto Yamasawa

Takeshi c/o Jtekt Corporation Ueda

Yasuhiro c/o Jtekt Corporation Saitou

An electric power steering device includes a first housing that supports an output shaft rotatable together with a driven member with a first bearing placed there between and a second housing that rotatably supports a driving member. The first housing includes an eccentric engagement section that is eccentric with respect to a first bearing holding section holding the first bearing. The eccentric engagement section is fitted to an engagement section of the second housing. When the center-to-center distance between the driving member and the driven member is adjusted, the eccentric engagement section of the first housing is rotated with respect to the engagement section of the second housing.

Electric power steering device

A torque sensor and an electric motor are supported by a steering column by which a steering shaft is rotatably supported. On a control board on which a control circuit that controls driving of an electric motor is mounted, a first terminal group and a second terminal group that are selectively connected to the torque sensor are respectively provided at a first end portion and a second end portion in a first direction parallel to a central axis of the steering shaft. A third terminal group that is connectable to the electric motor is provided at one end portion (third end portion) in a second direction perpendicular to the first direction.

Electric power steering system

A first gear set includes an input member that serves as a first gear and an inner ring that serves as a second gear. A first end of the inner ring is inclined with respect to the input member and is in mesh with the input member. The input member has a plurality of retention grooves that are formed in an input member body and a plurality of pins that are retained in the respective retention grooves and that respectively constitute teeth of the input member. The first end has a plurality of tooth grooves that are engageable with the pins. A resultant force of forces applied to each pin from the retention groove and the tooth groove urges the pin toward the retention groove.

Gear set and nutation gear set

An electric power steering system is provided which is capable of providing a favorable steering feeling without using compensation logics such as of inertia compensation and friction compensation. The electric power steering system includes road-noise suppression control means () for controlling a steering assist motor () in a manner to damp torque transmission in a higher frequency region representing road noises than a frequency region representing road information. A friction value of a steering mechanism (A) is decreased enough to allow the intrinsic vibrations of the steering mechanism (A) to appear. Rotor inertia of the steering assist motor () is set to a value small enough to allow the frequencies of the intrinsic vibrations to be present in the frequency region where the torque transmission is damped by the road-noise suppression control means ().

The invention provides a motor-driven power steering apparatus which can achieve a predetermined speed reduction ratio even in the case that the motor-driven power steering apparatus is constituted by a pair of spur gears or helical gears, and can secure a sufficient gear strength on the basis of a simple structure. In a motor-driven power steering apparatus in which a rotating torque of an electric motor () is transmitted to a steering shaft by a drive gear () provided in an output shaft of the electric motor () and a driven gear () provided in the steering shaft, and a speed reduction ratio is equal to or more than 3, the steering shaft and the output shaft of the electric motor () are arranged in almost parallel, a center distance between both the shafts is equal to or more than 35 mm and equal to or less than 90 mm, and the drive gear () is configured such that a number of teeth is equal to or more than 6 and equal to or less than 15, a module is equal to or more than 0.8 and equal to or less than 1.5, a tooth depth is equal to or less than 2.4 times of the module, and a pressure angle is equal to or more than 14.5 degrees and equal to or less than 30 degrees, and a torsion angle is equal to or more than 0 degrees and equal to or less than 40 degrees.

Motor-driven power steering apparatus

A reduction gear unit capable of reducing vibrations caused by gear rattle, while permitting some degree of backlash in a pair of gears, is provided. A reduction gear unit is so configured that a pinion shaft and a main gear shaft are disposed in parallel to each other, and a pinionmounted on the pinion shaft and a main gearmounted on the main gear shaft are arranged to mesh with each other, so as to transmit a rotation of the pinion shaft to the main gear shaft, and includes a housingthat encloses the pinionand the main gearwhere the housinghas an inner surface whose width, in a cross section perpendicular to an axial direction of the pinion shaft and the main gear shaft, perpendicular to an imaginary line that connects centers of the pinion shaft and the main gear shaft evenly increases from a pinion side toward a main gear side between ends of arcuate regions respectively enclosing the main gear and the pinion. The housingcontains a resin lubricant of a sufficient amount for immersing a part of a portion where the pinionand the main gearmesh with each other.

Reduction gear unit

A second housing is aligned with a first housing at a predetermined position using positioning means that determines the mounting position of the housing with respect to the first housing at the predetermined position; steering shaft supporting sections and output shaft supporting sections are provided in the first housing and the second housing respectively while the housings being mounted using screws or the like; the second housing is removed temporarily from the first housing; a steering shaft and an output shaft are supported using the steering shaft supporting sections and the output shaft supporting sections; and the second housing is aligned again with the first housing at the predetermined position using the positioning means and mounted.

Method for producing electric power steering apparatus

An electric power steering assembly includes an electric motor, a reduction mechanism for reducing the speed of an output rotation of the electric motor, and a reduction-mechanism housing accommodating therein the reduction mechanism. The electric motor includes: an output shaft rotatably supported by the reduction-mechanism housing, a motor housing formed integrally with the reduction-mechanism housing, a rotor, and a stator assembly accommodated in an annular space defined between the rotor and the motor housing. When the stator assembly is assembled in the annular space via an opening at an end portion of the motor housing, a guided portion on an outside circumference of a stator yoke is guided by a guide portion on an inside circumference of the motor housing.

Electric power steering assembly

A first alternating signal of which phase changes according to changes in the rotation angle of a first shaft is output, and a second alternating signal of which phase changes according to changes in the rotation angle of a second shaft capable of rotating elastically with respect to the first shaft is output. A phase difference correspondence signal of which waveform changes according to changes in the phase difference between the first alternating signal and second alternating signal is output. A value corresponding to the torque transmitted by the first and second shafts is found from the phase difference correspondence signal.

Torque sensor

A tilt steering apparatus comprises a lock lever rotatable around the axis of a supporting shaft. When a lock lever is rotated around the axis of the supporting shaft, a cam surface is rotated relative to a cam follower. As a result, the cam surface presses the cam follower against side plates of a fixed bracket, thereby achieving tilt locking. The cam surface has a plurality of slopes corresponding to a rotation stroke position of the lock lever. The operating torque of the lock lever at the time of a locking operation is reduced without increasing the range of the operating angle of the lock lever.

Growing community of inventors

Kashiwara, Japan

Yoshikazu Kuroumaru