Jidosha Kiki Co., Ltd.

Hiroshi Ohsaki

Takeshi Ohe

Yasuyoshi Emori

Ikuo Nomura

Shigeru Otsuka

A hydraulic reaction force apparatus of a power steering device includes an input shaft, an output shaft, the input and output shafts being connected with each other to be pivotal through a predetermined angle, reaction force arms connected integrally with the input shaft and projecting radially therefrom, a pair of output shaft guide holes sandwiching each reaction force arm and disposed to oppose each other in a direction perpendicular to the reaction force arms, reaction force plungers slidably disposed in the guide holes, and a reaction force mechanism for biasing the reaction force plungers against the reaction force arms by a reaction force applied to the reaction plungers and related to running conditions. Each reaction force plunger includes a metal cylindrical member having a hollow portion open at a side opposite to that of the reaction force arms and a damping member mounted in the cylindrical member.

Hydraulic reaction force apparatus of power steering device

A steering force controller for power steering apparatus is disclosed, which controls an oil pressure supplied to an oil pressure reaction chamber in accordance with a position of a spool valve which is caused to be displaced fore and aft in accordance with a vehicle speed. The spool valve is slidably fitted into a sleeve which is in turn disposed within a bore formed in a housing. The oil pressure supplied to the oil pressure reaction chamber can be controlled in accordance with the displaced position of the spool valve with respect to the sleeve. A regulating member is provided for causing an axial displacement of the sleeve, thus facilitating a regulation of a relative position between the spool valve and the sleeve.

Steering force controller for power steering apparatus

A hydraulic reaction force apparatus for a power steering system includes input and output shafts, a flange, balls, a reaction force receiving portion, a hydraulic reaction force chamber, and an annular reaction force piston. The input and output shafts are accommodated in a body. The flange is formed on one of the input and output shafts and has axial through guide holes. The balls are movably fitted in the guide holes, respectively. The reaction force receiving portion is formed on the other one of the input and output shafts to axially receive the balls. The hydraulic reaction force chamber is formed at a position opposite to the reaction force receiving force receiving portion with respect to the flange. The reaction force piston is movably and coaxially fitted on the output shaft with a clearance to urge the balls against the reaction force receiving portion so as to generate a restriction force corresponding to a reaction force oil pressure. The restriction force acts between the input and output shafts. Seal rings are disposed between the reaction force piston and the body and between the reaction force piston and the one of the input and ouput shafts.

Hydraulic reaction force apparatus for power steering system

Inlet passages and two sets of discharge passages are communicated with a pair of pump chambrs formed in a pump cartridge in a pump body. A pair of spool valves respectively acting as a flow quantity control valve and a pressure sensitive type flow path switchng valve are formed in parallel in the pump body in directions perpendicular to the axis of the pump.

Balanced vane type oil pumps

A vehicle power steering apparatus for performing power steering by rotating a motor in accordance with a steering torque acting on input and output steering shafts and driving a steering direction control unit to perform power steering, comprises a sensor for generating an electrical signal corresponding to a displacement of a movable member displaced by a rotational force acting on the steering wheel; a controller for rotating the motor at a torque represented by the electrical signal during an ON time of the electrical signal generated from the sensor; and moving means for moving the movable member in a direction to cancel the displacement of the movable member driven by the motor.

Power steering apparatus

In an oil pump having two pump cartridges each acting as independent pumps, a pair of suction passages and a pair of discharge passages opened in a pair of pump chambers in the pump cartridges are formed in one pump body secured to one side of the cartridges, a flow control valve is contained in an opening extending in an axial direction of the pump body, and a pressure sensitive flow passage change over valve is contained in another valve opening perpendicular to the valve opening. The two valve openings are communicated with the discharge and suction openings.

Balanced vane oil pumps

A flow path switching valve is provided, operating to merge hydraulic fluid from a plurality of pumps in accordance with a magnitude of a loading applied to a hydraulic unit, and a variable orifice is defined adjacent to the valve. A flow control valve is also provided for returning part of the hydraulic fluid to a tank, and operates in accordance with the throttle opening of the variable orifice which changes in accordance with the operation of the flow path switching valve.

Apparatus for supplying hydraulic fluid

To supply hydraulic fluid to a hydraulic apparatus, a plurality of pumps are used. One of the pumps is used as a main pump while the remaining pump or pumps are used as sub-pumps. A flow path switching mechanism selectively disconnects the sub-pumps from a supply passage to the hydraulic apparatus. In this manner, a required minimum supply of hydraulic fluid is assured with a simple arrangement while eliminating wasteful energy loss and reducing the dissipation of the horsepower. A reliable operation is maintained without any adverse influence upon the hydraulic apparatus. In one embodiment, a pair of pumps, and a control including a pair of switching valves operating as a pressure sensor and a flow controller are assembled into a pump body. The switching valves assure a reasonable supply of hydraulic fluid to the hydraulic apparatus while minimizing the dissipation of the horsepower. At this end, a pump receiving space is defined within the pump body, and a pair of valve openings are formed around the space and close to each other so that their axes extend parallel to each other. Openings and passages are cast into the pump body or formed by a simple boring operation to provide a communication between these elements. In this manner, the overall arrangement is simple and the manufacturing and assembly are facilitated, reducing the manufacturing cost. A reduction in the size and the weight of the overall unit is achieved.

Growing community of inventors

Higashimatsuyama, Japan

Hiroshi Ohsaki