Honda Giken Kogyo Kabushiki Kaisha

Yoshio Kakizaki

Hirokazu Kitazawa

Hiroshi Furumi

Junichi Yoshida

Osamu Tsurumiya

Hiroaki Horii

Hisao Asaumi

Fumihiro Morishita

Shinji Suto

Hitoshi Suda

Tomoaki Sugano

Kazuhiko Inaba

Takashi Kuribayashi

Kazuhiro Kishimoto

Yoshitaka Katashima

Kunio Shirakawa

Susumu Ohta

Satoshi Shimada

A motor driving method for a steering apparatus for applying an auxiliary steering force to a steering system with two motors. When the two motors are driven, a first one of the two motors is operated first. Thereafter, the other, second motor is driven, whereby smooth steering is effected.

Steering system for vehicle

Steering apparatus for transmitting a driving force of a motor through a gear mechanism to a rack shaft of a steering system and applying the driving force to steering road wheels in a steering direction. The apparatus has first and second motors. In the transmission of driving forces from output shafts of the first and second motors to the rack shaft, the phases of the two motors are essentially staggered by 180 degree.

An electric power steering apparatus with a plurality of motors for applying a force to steering road wheels in a steering direction with mechanism which applies an increase in allocation of auxiliary steering force to an operating motor when at least one of the motors has failed.

Provided is a rear wheel steering device which includes a rotary shaft having a pair of threaded sections of mutually opposite senses, and a pair of slide members supported in a rotationally fast manner, and having threaded sections which engage the corresponding threaded sections of the rotary shaft so as to be moveable in mutually opposite axial directions as the rotary shaft is turned in either direction, and a pair of clutch units each interposed between a corresponding one of the slide members and the slide shaft for selectively coupling them in an axially fast manner. Thus, the steering direction can be determined by selectively engaging either one of the clutch units, and the magnitude of the steering angle can be determined by turning the rotary shaft with an electric motor in either direction. In particular, when it is desired to bring the steering device to the neutral position, it can be achieved simply by turning the electric motor in a prescribed direction without regard to the current state of the steering device.

Rear wheel steering device having fail-safe features

In an electric steering actuator comprising an electric motor having a hollow output shaft, a steering shaft passed through the hollow center of the output shaft of the electric motor, and a ball-screw mechanism provided between the output shaft and the steering shaft for converting the rotary movement of the output shaft into a longitudinal movement of the steering shaft. The ball-screw mechanism comprises a threaded section of the steering shaft, and a nut member which threadably engages with the threaded section of the steering shaft via steel balls, and is secured to the output shaft of the electric motor via a serration coupling or the like which achieves an axially free but rotatively fast coupling between the two parts. Thus, the overall axial dimension of the actuator can be reduced, and the step of joining these two parts is significantly simplified in terms of both effort and time while the number of component parts is also reduced. In particular, by installing the ball-screw mechanism in the first casing section in an axially immobile manner, removal of the rotor or the motor assembly is substantially simplified, thereby making the actuator easier to manufacture and service. Also, the motor can be interchanged without affecting the ball-screw mechanism.

Electric steering actuator

In an electric steering actuator comprising an electric motor having a hollow output shaft, a steering shaft passed through the hollow center of the output shaft of the electric motor, and a ball-screw mechanism provided between the output shaft and the steering shaft for converting the rotary movement of the output shaft into a longitudinal movement of the steering shaft, a rotation preventing mechanism is provided for preventing the rotation of the steering shaft around its axial line. The rotation preventing mechanism comprises a guide pin extending in the casing in parallel with the axial line of the steering shaft, and a fork member engaging the guide pin between two prongs thereof. Because the rotation preventing mechanism can be formed by using a guide pin made of a stock steel or other metallic member, such as a cold finished steel bar, the manufacturing cost can be reduced. Furthermore by using a fork member defining an open slot for engagement with the guide pin, the assembling process is simplified, thereby reducing the manufacturing cost. In particular, by interposing a plastic slider between the pin and the fork member, metallic noises are avoided, and a smooth operation is ensured at a low cost.

An electrically operated steering apparatus for use on a motor vehicle has a cylindrical housing, an axially movable rack shaft disposed in the housing for steering steerable wheels coupled to the rack shaft, and an electric motor disposed in the cylindrical housing around the axially movable shaft for moving the axially movable shaft. A power supply for supplying electric energy to the electric motor is disposed outside of the cylindrical housing. A motor control circuit for generating a motor control signal based on a detected steering torque is disposed in the cylindrical housing. A motor driver circuit is disposed in the cylindrical housing for energizing the electric motor with the electric energy supplied from the power supply based on the motor control signal. An insert-molded board is disposed in the housing and electrically interconnecting the electric motor, the motor control circuit, and the motor driver circuit. The insert-molded board comprises electric conductors and a body of synthetic resin molded around the electric conductors.

Growing community of inventors

Wako, Japan

Yoshio Kakizaki