Remote-controlled hydropneumatic shock absorber

Abstract

A shock absorber comprises a sliding tube sealed at one end which is provided with an attachment for one of the two parts of the vehicle which needs cushioning and a stem presenting at one end another attachment for the other of the two parts of the vehicle and at the other end a piston engaged within the sliding tube to make a sliding side seal with the tube. The piston is equipped with valve means controlling the flow of a liquid between first and second pressure chambers formed within the sliding tube by the opposed faces of the piston. The first pressure chamber is traversed by the stem. The stem is provided with a longitudinal duct which through radial ports is communicating with the first chamber and which communicates with the second chamber through a sized end hole with which the tip of the needle of a variable throttle cooperates. The other end of the throttle presents a thickened head engaged within a portion of the duct of the stem to make a sliding side seal, the duct being filled with liquid and connected with a pressure chamber of a remote control device. The pressure chamber is of the hydraulic cylinder and piston type whereby it is possible by axial displacement of the cylinder to change the axial position of the needle of the throttle and therefore also the size or gap of the end hole of the throttle in order to modify the shock absorber braking force.