Abstract: In a vehicle which is provided with a power steering device having an oil passage or an oil chamber whose pressure increases to a high level as a steering angle becomes large; and a damper device consisting of a cylinder filled therein with a working oil and a piston fitted slidably in the cylinder to divide the interior thereof into upper and lower oil chambers, the damper device being adapted to damp the relative movements of a chassis and a wheel support member, the damper device is characterized in that it is provided with a variable throttle mechanism interposed between the upper and lower oil chambers and operable to increase its degree of restriction in proportion to the rise of pressure in the oil passage or oil chamber of the power steering device. This simply constructed device is obtained at a low cost and enables the damping force to vary continuously without use of sensors and processor.

Abstract: A power steering device for vehicles having a simple construction, which is capable of minimizing the frictional loss of a hydraulic pump as well as the power consumption of the hydraulic pump and engine.

Abstract: An improved power steering device which has a pinion shaft connected with a steering wheel, a rack rod which is connected with steerable wheels and whose rack is in mesh with the pinion of the pinion shaft in the gear box, a power cylinder for hydraulically actuating the rack rod, and a changeover valve for selectively connecting the first and second hydraulic chambers of the power cylinder with the hydraulic pressure source and the oil reservoir. The pinion shaft is rotatably supported in the oscillating cage which is rotatably mounted on the gear box in a manner such that the axis of the oscillating cage is offset a certain distance from the axis of the pinion shaft, whereby the oscillating cage rotates about its axis when the steering torque is applied to the pinion shaft. The oscillating cage is connected with the changeover valve so that the latter is actuated by the rotary movement of the oscillating cage.

Abstract: A steering mechanism for vehicle equipped with a power steering system, the steering mechanism including a resilient element, such as a torsion bar, which is interposed in a path of torque transmission between a steering wheel and a power steering unit which provides an increased steering reactive force in proportion to vehicle speed. The steering mechanism includes a damper arrangement disposed between two relatively rotatable members which are operably associated with each other through the resilient element. The damper arrangement attenuates torsional vibrations of a first one of the relatively rotatable members disposed on the side of the steering wheel, such vibrations being caused by the interposed resilient element and the moment of inertia of the steering wheel.

Abstract: Power steering apparatus for a vehicle comprising a rack rod operatively connected to a steering wheel and supported in a steering gear casing, the rack rod being drivable by a power cylinder consisting of an outer cylinder fixed to the steering gear casing, an inner cylinder disposed in the outer cylinder and fitted into the steering gear casing, and a piston mounted on the rack rod to divide the interior of the inner cylinder into first and second oil chambers. A control valve is mounted on the lower surface of the steering gear casing for controlling the operation of the power cylinder. The second oil chamber is in communication with the outer cylinder via the spaces between the coils of a coil spring, the inner cylinder being supported in floating state on the outer cylinder by the coil spring. A pair of parallel, annular or semi-annular oil passages are provided in that portion of the steering gear casing which is engaged with the inner cylinder.

Abstract: A power steering apparatus for a vehicle comprising a valve housing provided with a rotary type valve body rotatable in one direction or another by a turning operation of a steering shaft. An oil supply port is connected to an oil pressure pump that is selectively connected to either of one or another of cylinder ports connected to respective left and right chambers of a power cylinder. The valve body is provided with an intermediate partition plate extending into an oil pressure reaction chamber in the valve housing to divide the chamber into areas on opposite sides of the partition plate. The resultant pair of areas extend respectively on either side in the turning direction of the valve body, and the respective areas are connected to one or the other of the cylinder ports.

Abstract: An improved power steering device which has a pinion shaft connected with a steering wheel, a rack rod which is connected with steerable wheels and whose rack is in mesh with the pinion of the pinion shaft in the gear box, a power cylinder for hydraulically actuating the rack rod, and a changeover valve for selectively connecting the first and second hydraulic chambers of the power cylinder with the hydraulic pressure source and the oil reservoir. The pinion shaft is rotatably supported in the oscillating cage which is rotatably mounted on the gear box in a manner such that the axis of the oscillating cage is offset a certain distance from the axis of the pinion shaft, whereby the oscillating cage rotates about its axis when the steering torque is applied to the pinion shaft. The oscillating cage is connected with the changeover valve so that the latter is actuated by the rotary movement of the oscillating cage.

Abstract: A power steering apparatus for a vehicle comprising a valve housing provided with a rotary type valve body rotatable in one direction or another by a turning operation of a steering shaft. An oil supply port is connected to an oil pressure pump that is selectively connected to either of one or another of cylinder ports connected to respective left and right chambers of a power cylinder. The valve body is provided with an intermediate partition plate extending into an oil pressure reaction chamber in the valve housing to divide the chamber into areas on opposite sides of the partition plate. The resultant pair of areas extend respectively on either side in the turning direction of the valve body, and the respective areas are connected to one or the other of the cylinder ports.

Abstract: A power steering apparatus for a vehicle comprising a center open type changeover valve which, on turning of a steering shaft, is moved to be changed over from a neutral straight running position to either of left and right steering positions so that an oil supply passage connected to an operation oil pressure source and an oil discharge passage connected to a return tank are selectively and respectively connected to the left and right chambers of a power cylinder. On one side of the changeover valve is at least one oil pressure reaction chamber which is connected through an oil passage to the oil supply passage to urge the changeover valve to return to its neutral straight running position on the changeover movement of the changeover valve in either direction. The operation oil pressure source is so constructed to provide increased delivery amount according to increase of vehicle speed.

Abstract: An oil hydraulic power steering device of the rack and pinion type which includes a rack rod supported for lateral oscillation about a fulcrum adjacent one end thereof and a power actuator comprised of a piston secured to the rack rod, an outer cylinder, and an inner cylinder in which the piston is slidably fitted and which is floatingly supported in the outer cylinder. The device further includes a spring for normally biasing the rack rod against the pinion and a mechanism for engaging the normally free end of the rack rod while laterally displacing the rod end to increase the backlash in the rack and pinion gearing as the rack rod approaches the end of its stroke. There is no excessive pressure of contact occurring between the meshing gear teeth and the backlash is self-adjustable as the teeth wear down.

Abstract: Power steering apparatus comprising a displaceable changeover value operated in one direction or the other by turning of a steering shaft so that an oil supply passage connected to an oil pressure pump is placed into communication with either a right chamber or a left chamber of a power cylinder. At least one external oil pressure reaction chamber is arranged to be reduced in volume by the operation in either direction of the changeover valve, the oil pressure reaction chamber being in communication through a first throttle with the oil supply passage and through a second throttle with an exterior oil tank. At least one of the two throttles is variable in size in proportion to vehicle speed so that the ratio of the area of opening of the first throttle relative to the second throttle can be increased according to increase of vehicle speed.

Abstract: A power steering apparatus of a vehicle having a changeover valve operated in one direction or the other according to the turning of a steering shaft so that a supply oil passage connected to an operational oil pressure source is connected selectively to the left or right chamber of a power cylinder. At least one oil pressure reaction chamber is arranged externally of the changeover valve to be reduced in volume by the operation in either direction of the changeover valve to oppose such operation. A control valve connects the oil pressure reaction chamber to the supply oil passage via a second oil passage. A divergent exhaust oil passage is connected to the second oil passage via a throttle.

Abstract: Power steering apparatus comprising a changeover valve adapted to be operated in one direction or the other by turning of a steering shaft so that a supply oil passage connected to an operational oil pressure source is selectively connected to a right or left chamber of a power cylinder. At least one external oil pressure reaction chamber is arranged to be reduced in volume by the operation in either direction of the changeover valve to resist displacement thereof, the oil pressure reaction chamber being connected through a first oil passage to a control pressure source for delivery of oil at a pressure corresponding to vehicle speed. The first oil passage is connected through a second oil passage to the supply oil passage and a control valve is mounted in the second oil passage to be opened when the pressure within the first oil passage is higher by a predetermined value than the pressure within the supply oil passage.