Abstract: An air chamber (53) of a damping force adjusting mechanism (49) disposed in a hydraulic shock absorber (3) of a damping force adjusting type communicates with an air chamber (7) of an air spring through a tubular path (57). A free piston (51) is transferred in accordance with the pressure of the air chamber and a spool (46) is transferred to shift a damping force. The damping force presents a soft characteristic both on the extending side and on the retracting side in a usual status, presents a hard characteristic on the extending side and a soft characteristic on the retracting side when the pressure of the air chamber is high, and presents a soft characteristic on the extending side and a hard characteristic on the retracting side when the pressure of the air chamber (7) is low. The damping force can be obtained, which approximates the damping force control on the basis of a so-called sky-hook theory.

Abstract: The present invention provides a suspension control device with which the damping coefficient of the suspension can be easily adjusted on the basis of only the vertical vibration of a body of a vehicle, without measurement of the relative velocity or the relative displacement between the body and the wheel along the vertical direction. The absolute velocity of the body 1 is calculated on the basis of the detected signal of the acceleration sensor attached to the body 1, then the rotation angle .theta. of the movable plate is calculated on the basis of the absolute velocity, and the movable plate is rotated in the predetermined direction by the rotation angle .theta.. Accordingly, the damping coefficient is adjusted so that the coefficient in the extension of the shock absorber becomes larger and the coefficient in the compression of the shock absorber becomes smaller, or so that the damping coefficient in the extension becomes smaller and the coefficient in the compression becomes larger.

Abstract: A suspension control system has a relative displacement sensor for detecting a relative velocity between a vehicle body and a wheel, and a controller which sets a relatively large value as a damping coefficient for the extension stroke of a hydraulic shock absorber, which is provided between the vehicle body and the wheel, when the magnitude of the relative velocity in the direction of the extension stroke exceeds a preset reference value, with priority to control based on the absolute velocity of the vehicle body. When the magnitude of the relative velocity between the vehicle body and the wheel in the direction of the extension stroke exceeds the reference value during running of the vehicle, for example, due to falling of the wheel into a depression, the damping coefficient for the extension stroke is set at a relatively large value with priority to the control based on the absolute velocity. Accordingly, when the wheel falls into a depression, occurrence of full bounce is prevented.

Abstract: A damping force control type hydraulic shock absorber includes a cylinder having a hydraulic fluid sealed therein. A piston is slidably fitted in the cylinder to divide the inside of the cylinder into two chambers. A main hydraulic fluid passage provides communication between the two chambers and has a damping force generating mechanism. A bypass passage also provides communication between the two chambers. A cylindrical guide member is provided in the bypass passage to provide communication between two portions of the bypass passage which lead to the two chambers, respectively, through ports provided in the side wall of the guide member. A cylindrical shutter is rotatably fitted in the guide member. The shutter has openings capable of aligning with the ports. The ports and the openings cooperate to provide a damping force which changes generally linearly as the shutter rotates.

Abstract: A suspension controller includes a controller that actuates devices for charging and discharging a pressure fluid into and from front and rear wheel-side cylinders. The controller has first-order lag circuits including first-order lag elements with different time constants. In the early stage of a steering operation, the rear wheel-side cylinders carry a higher travelling load than that shared by the front wheel-side cylinders on the basis of transverse acceleration data detected with a transverse acceleration sensor, so that excellent vehicle turning characteristics can be obtained. After a predetermined time has elapsed, the front wheel-side cylinders are also subjected to control based on the transverse acceleration data, so that the load is shared between the front and rear wheel-side cylinders in a well-balanced manner. Thus, excellent convergence is obtained.

Abstract: A rotary actuator comprising a first rotor rotatable around a first axis and an axial end surface with a plurality of circumferentially spaced and axially projecting first projections, attending therefrom a second rotor rotatable around a second axis which is not coincident with the first axis, the second rotor having an axial end surface with a plurality of circumferentially spaced and axially projecting second projections extending therefrom, and a rotating mechanism being connected to the second rotor to rotate it around the second axis. The second projections project in a direction opposite to that of the first projections to cooperate therewith such that either one of the second projections engages with either one of the first projections to rotate the first rotor through a predetermined angle.

Abstract: A rotary actuator has a Geneva wheel having in one end surface thereof an annular central recess and a plurality of angularly equally spaced and radially extending grooves connected to the central recess, a driving rotor connected to a rotary driving source and rotatable around an axis eccentric with respect to the Geneva wheel, a driving pin mounted on the driving rotor and engaging selectively with one of the grooves and the central recess in the Geneva wheel, an arcuate wall defined on a part of the circumferential wall of the driving rotor, and a plurality of correspondingly shaped arcuate walls formed on the Geneva wheel and cooperating with the arcuate wall of the driving rotor when the driving pin of the driving rotor engages with the central recess thereby preventing the rotation of the Geneva wheel with respect to the driving rotor.