Telescopic hydraulic shock absorber - has secondary valve to reduce resistance at high piston speed

摘要

The cylinder (1) of a telescopic hydraulic shock absorber is provided with a piston (2) which embodies two valves (14, 17). When relatively low shocks occur the fluid in the chamber (7) flows through the orifice (12), lifting the valve (14) off its seat and flowing out through the orifice (13). With very high shocks the pressure of the fluid in the space (20) is increased so that the piston (17) is forced upwards against the spring (18) allowing fluid to flow through the orifices (21, 22) into the space (20) and out through the orifice (13). This increases in flow reduces the piston resistance, allowing it to move at a higher speed and so absorb higher shock loads.