Patent ID: 7322449

Claim:
A hydraulic shock absorber comprising: a cylinder in which a hydraulic fluid is sealably contained; a piston which is slidably fitted into the cylinder; a piston rod having one end thereof connected to the piston, the other end of the piston rod extending to an outside of the cylinder; a main valve for controlling a flow of the hydraulic fluid from an upstream-side chamber to a downstream-side chamber generated according to a sliding movement of the piston, to thereby generate a damping force; a back-pressure chamber for applying a back pressure in a direction for closing the main valve and controlling opening of the main valve by means of the back pressure in the back-pressure chamber; a back-pressure chamber inlet fluid passage for introducing the hydraulic fluid from the upstream-side chamber into the back-pressure chamber; a downstream-side orifice for allowing communication between the back-pressure chamber and the downstream-side chamber; and a check valve for allowing only a flow of the hydraulic fluid from the downstream-side chamber to the back-pressure chamber.