Adjustable shock absorber, especially for motor vehicles

摘要

An adjustable shock absorber for motor vehicles comprises a cylinder containing damping fluid, a piston rod arranged to be axially displaceable in the cylinder, and a damping piston secured to the inner end of the piston rod. The damping piston divides the cylinder chamber into two working chamber compartments and is provided with fluid flow passages which produce damping forces, the effective cross-section of these flow passages being controllable by a throttling member and an electromagnetic drive controlling the throttling member, with the electromagnetic drive including a coil winding which is mounted in the damping piston. In order to achieve improved control of the damping force the throttling member is under the influence on the one hand of the fluid pressure difference between the two working chamber compartments and on the other hand of a restoring force which is created by the electromagnetic drive. Preferably, a hydraulic compensating device which reinforces this restoring force is provided between the throttling member and the electromagnetic drive which counteracts the hydraulic displacement of the throttling member.