The working principle of the double acting shock absorber

The working principle of the double acting shock absorber is that: in the compression stroke, namely the automobile wheels move close to the automobile body, the shock absorber is compressed, the piston 3 of the hydraulic oil shock absorber moves downward, the volume of the lower cavity of the piston is decreased, the oil pressure rises, the oil flows to the cavity (upper cavity) above the piston via the passing valve 8, and the partial space of the upper cavity is occupied by the piston rod 1, so that the increased volume of the upper cavity is less than the decreased volume of the lower cavity, some oil pushes the compression valve 6 and flows back to the oil cylinder 5, and the oil-saving action of these valves forms the damping force against the compressed motion of the suspension; in the stretching stroke of the shock absorber, the wheels are relatively away from the automobile body, the shock absorber is stretched, the piston of the shock absorber moves upward, the oil pressure of the lower cavity of the piston rises, the passing valve 8 is closed, the oil in the upper cavity pushes the stretching valve 4 and flows to the lower cavity; and because of the existence of the piston rod, the oil flowing from the upper cavity is not enough to fill up the increased space of the lower cavity, so that a certain vacuum degree is generated in the lower cavity, the oil in the oil storage cylinder pushes the compensation valve 7 and flows to the lower cavity for supplement, and the throttling action of these valves forms the damping force against the stretching motion of the suspension.