Rotary shock absorber having vanes with radial flow clearance

摘要

A rotary shock absorber suitable for use in a suspension system of a vehicle. The shock absorber is provided with a housing and a rotary shaft supported by the housing for relative rotation thereto. A pressure chamber is formed in the housing and a rotor having a pair of blades is received within the pressure chamber. Further, a pair of partition walls are formed within the pressure chamber to define first and second chambers at both sides of each blade, and the first and second chambers are communicated with each other through throttles. When the rotary shaft is rotated, a high viscous fluid filled within the first and second chambers flows therebetween through the throttles. Due to the flow resistances of the throttles, pressures are generated in the first or second chambers. This pressure generation is used to generate a damping force. The shock absorber is further provided with a mechanism which changes the characteristic of damping force generation depending on the rotational direction of the rotary shaft. In some embodiments, the shock absorber has a stopper function which drastically increases the damping force at the stroke ends.