Variable damping shock absorber and method of adjusting the damping characteristics of a shock absorber

摘要

The present invention provides a low cost, variable damping shock absorber. The shock absorber according to the invention comprises a damper tube (4) with a sealing surface (10), a damper fluid arranged inside the damper tube (4) and a damper piston (1) arranged movably within the damper fluid. A circumferential groove (5) is formed in the damper piston (1), in which a pressing fluid and a sealing element (3) extending in the circumferential groove (5) and directly adjacent to the pressing fluid are located. The sealing element (3) is designed to exert on the sealing surface (10) of the damper tube (4) a contact pressure, which is adjustable by an adjustable fluid pressure of the pressing fluid. The damper fluid and the pressurized fluid do not communicate with each other. The shock absorber comprises means (13) acting on the pressing fluid for adjusting the pressure in the pressing fluid directly and without interposition or utilization of the damper fluid, or the shock absorber is provided with means (13) for directly and without interposing or utilizing the damper fluid on the pressing fluid Setting the pressure in the press fluid connectable.