Honda Giken Kogyo Kabushiki Kaisha

Takashi Kohata

Masaru Abe

Yoshimichi Kawamoto

Toru Yasuda

Ikuo Nonaga

Osamu Tsurumiya

Masami Ogura

Mitsuya Serizawa

Kazuhiro Seki

Nobuyoshi Asanuma

Toshio Yahagi

Yoshihiro Iwagawa

Masataka Izawa

Toshihiko Aoyama

Norio Ukai

Yuichi Okada

Katsuyuki Miyashita

Ryozou Yoshizawa

Yukio Yoneda

A power steering system is disclosed which automatically corrects unexpected variations in the path of a vehicle without requiring a driver to make corrections. A rotary valve in the power steering system includes an inner sleeve connected to a steering wheel, an outer sleeve connected to a pinion shaft meshed with a rack bar, and a torsion bar coupled to the inner sleeve and the pinion shaft. The rotary valve switches oil passages communicating with a power cylinder by means of relative rotation between the inner sleeve and the outer sleeve to thereby assist in steering. The outer sleeve and the pinion shaft are connected to each other for slight relative rotation through an elastomer or resilient connecting member. If an unexpected variation in path is produced in the vehicle, the outer sleeve is rotated by the operation of a torque motor which causes the operation of the rotary valve, thereby moving the power cylinder whereby a steering force is produced for correcting the variation in path.

Power steering system

A vehicle steering system, suitable for steering the rear wheels of a four wheel steering vehicle, comprising a steering rod received in a housing assembly so as to be moveable in the longitudinal direction, an indicator member is connected to the steering rod by way of a connecting arm member extending radially from the steering rod so that the steering output of the steering system may be detected by cooperation between a sloping surface provided in the indicator member and a stroke sensor mounted on the housing assembly and engaged to the sloping surface and/or so that the rotation of the steering rod around its central axial line may be prevented. Since the indicator member is connected to a free end of the connecting arm member in such a manner that the indicator member may move away from and toward the steering rod and move angularly relative to the connecting arm member, a favorable movement of the indicator member may be ensured during the operation of the steering system without requiring any undue precision in the distance and the angular relationship between the steering rod and the indicator member. Thus, an economy of the manufacturing cost can be gained without in any way sacrificing the accuracy or the reliability of steering angle detection in the steering system.

Vehicle steering system with a steering output sensor

An electric power steering system which additionally includes a radial arm extending from a steering rod, an axial shaft extending in parallel with the axial center line of the steering rod, an axial bore formed in the casing of the system for guiding axial movement of the axial shaft substantially without any play, and a spring member urging the axial shaft against a side wall of the axial bore. Thus, rotation of the steering rod around its axial center line may be prevented with a relatively small force. Therefore, no excessive force needs to be applied to the axial shaft, and the axial shaft would not encounter any substantial resistance to its axial movement. The axial shaft may be provided with a groove extending along one side thereof in parallel with the axial central line of the axial shaft and provided with a bottom surface which slopes along its lengthwise direction, and the casing may support a steering rod displacement sensor having a spring-loaded retractable plunger serving as a measuring end and abutting the sloping bottom surface of the groove. Thus, the steering rod displacement sensor may be provided with a simple structure which makes it suitable to be mounted in a very limited space in the power steering system. If desired, the steering rod displacement sensor may also serve as the spring member for removing play between the axial shaft and its axial bore. This electric power steering system is suitable for use in front and rear wheel steering vehicles.

Electric power steering system

A front and rear wheel steering system for a vehicle which transmits a steering input from a front wheel steering gear box to a rear wheel steering gear box via a coupling shaft as a rotation thereof around its longitudinal line and varies a steering gear ratio of rear wheels to front wheels according to the speed of the vehicle. A steering rod for steering the rear wheels with its longitudinal movement is provided with a crank portion which is engaged with a swing shaft pivotally attached to the coupling shaft via a pivot shaft perpendicular thereto so as to perform a gyrating motion around an extension line of the coupling shaft and thereby move the steering rod along its longitudinal direction to achieve a steering action of the rear wheels. The steering rod can be rotated around its longitudinal line according to the vehicle speed so as to displace the crank portion relative to the extension line of the coupling shaft and change the relationship between the rotational angle of the coupling shaft or the steering input to the front wheel steering gear box and the longitudinal movement of the steering rod or the steering angle of the rear wheels.

Front and rear wheel steering system for a vehicle

A four-wheel-steering system includes a rear wheel steering mechanism for turning rear wheels in response to energization of an actuator. A locking device is responsive to de-energization of the actuator for locking gears and a rack shaft to prevent the rear wheels from being turned. The locking device includes a longer arm on which first and second gears are rotatably mounted, a shorter arm pivotally coupled to the longer arm, a stopper coupled to the shorter arm and engageable with the second gear, and a spring acting on the stopper for normally urging the stopper into engagement with the second gear, the actuator comprising an electric motor angularly movable with respect to the second gear.

Rear wheel steering mechanism with locking control for

A rear wheel steering device in a four-wheel-steerable vehicle includes a rod member having opposite ends coupled to tie rods for turning rear wheels, an electric motor, and a screw mechanism for converting rotation of the electric motor to axial motion of the rod member. The stator and rotor of the electric motor are disposed coaxially with the rod member, the motor and the screw mechanism being juxtaposed with respect to each other in the axial direction of the rod member. The screw mechanism comprises a threaded portion on the rod member and a nut engaging the threaded portion, the nut being axially pre-loaded.

Rear wheel steering device for vehicle with four steerable wheels

A steering system for a motor vehicle having front road wheels and rear road wheels which are steerable includes a rear wheel steering mechanism for steering the rear road wheels based on a vehicle speed and a front wheel steered angle. The rear wheel steering mechanism, has a correcting mechanism fo varying a rear wheel steering force dependent on the vehicle speed.

Steering system for motor vehicle with steerable front and rear wheels

In a four-wheel steering system for steering front and rear wheels of a vehicle in opposite directions in a low vehicle speed range, a rear wheel steering method steers the rear wheels more greatly in a predetermined low vehicle speed range in which a vehicle is usually steered by large angles than in a very low vehicle speed range lower than the predetermined range. The method insures a small turn of the vehicle while suppressing a change in the radius of a turn relative to the operation of a steering wheel immediately after the start of the vehicle.

Rear wheel steering method for a four wheel steering vehicle

A four-wheel steering motor vehicle adapted to prevent a steering ratio of the rear wheels to the front wheels from varying at the time of sudden braking when the pressure of a brake liquid is reduced by an antilock brake unit. This vehicle includes a front wheel steering unit for steering the front wheels in accordance with angular movement of a steering wheel, a rear wheel steering unit for steering the rear wheels, steering control unit for determining a target steering angle of the respective rear wheels based on a vehicle speed and a front wheel steering angle and for controlling the rear wheel steering unit in such a manner that the rear wheel steering unit steers the rear wheel until a rear wheel steering angle reaches the target value, an antilock brake unit for calculating a slip coefficient of each wheel based on a sensed rotating speed of each wheel and for reducing the pressure of a brake liquid being supplied to a brake of the individual wheel when the slip coefficient of the wheel exceeds a predetermined value. The steering control unit controls the rear wheel steering unit so as to substantially prevent the rear wheel steering angle from varying when the pressure to the brake liquid is reduced by the antilock brake unit.

Four-wheel steering motor vehicle

The steering operation of a motor vehicle with steerable front and rear road wheels is controlled by steering the rear road wheels with an actuator such as an electric motor which produces a steering force dependent on a deviation of the actual rear wheel steering angle from a target rear wheel steering angle. The rear road wheels are thus controlled with a characteristic dependent on the coefficient of friction of a road on which the motor vehicle travels and the steering speed at which the motor vehicle is steered. Typically, a steering control method comprises the steps of detecting the steering angle of the front road wheels, determining a target steering angle for the rear wheels based on the steering angle of the front road wheels, detecting the actual steering angle of the rear road wheels, calculating a steering angle deviation of the actual rear wheel steering angle from the target steering angle, determining a rear wheel steering force based on the steering angle deviation, and steering the rear road wheels to the target steering angle with the determined rear wheel steering force.

Method of and apparatus for controlling steering operation of a motor

A method of and an apparatus for controlling rear road wheel camber of a four-wheel-steerable vehicle having front and rear road wheels steerable in the same or opposite directions. The camber with respect to ground of at least the rear road wheel on the outer side of a cornering curve followed by the vehicle is controlled. The apparatus includes detectors for detecting the direction in which the rear road wheels are steered with respect to the front road wheels, the self-aligning torque on the front road wheels, and the steering force acting on a steering wheel, camber varying devices associated with rear wheel suspensions, actuators for operating the camber varying devices, and a control unit responsive to detected signals from the detectors for applying a control signal to at least one of the actuators to control the camber of at least the rear road wheel on the outer side of the cornering curve when the rear wheels are steered.

Method of and apparatus for controlling camber of rear wheels of

A steering angle detector comprises a differential transformer. The steering angle detector includes a rod member extending substantially transversely of the vehicle body and axially movable in response to steering action of the vehicle body, a metallic core mounted on the rod member, and primary and secondary coils disposed around the core in slightly spaced relation thereto.

Steering angle detector

An automobile suspension includes a suspension member coupled to a vehicle body, a disc-shaped actuator mechanism detachably supported on the suspension member, and a knuckle having a swingable support shaft swingably supported for swinging movement about a central pivot through which the axis of the disc-shaped actuator mechanism passes, the knuckle being adapted to support a wheel rotatably. The disc-shaped actuator mechanism includes a pair of actuators disposed thereon at respective positions spaced substantially equally from the central pivot and located on at least one straight line passing through the central pivot, the actuators pivotally supporting the knuckle, respectively, for causing the knuckle to be angularly moved about the central pivot.

Automobile suspension

A steering gear box mount includes a resilient member interposed between a motor vehicle body and a steering gear box for allowing movement of the steering gear box. The mount also has a structure for limiting allowed movement of the steering gear box. The structure includes a mechanism for selectively rigidly fixing the steering gear box to a motor vehicle body, or a mechanism for continuously adjusting the allowed movement of the steering gear box.

Growing community of inventors

Saitama, Japan

Takashi Kohata