Patent ID: 7886882

Claim:
A pneumatic spring damper unit ( 1 ) with an extensionstage and a compression stage, having at least one moveably mounted expeller piston ( 2 ) and two expeller chambers ( 3 , 4 ) whose volumes are increased or decreased depending on the direction of movement of the expeller piston ( 2 ) and which are connected to one another by means of overflow ducts ( 6 , 7 ) in which a plurality of unidirectional throttle valves ( 16 , 16 ′, 16 ″, 17 , 17 ′, 17 ″, 17 ″′) are arranged with differing valve characteristics, with at least one of the throttle valves ( 17 ) being configured to damp natural frequencies in the range from 1 to 1.5 Hz, and at least one other throttle valve ( 17 ′) being configured to damp natural frequencies in the range from 10 to 40 Hz, wherein at least four throttle valves ( 16 , 16 ′, 16 ″, 17 , 17 ′, 17 ″, 17 ″′) are provided for each direction of flow and of which one is a bypass valve ( 17 ″′), one throttle valve ( 17 ) serves a frequency range from 1 Hz to 1.5 Hz, one throttle valve ( 17 ′) serves a frequency range from 10 Hz to 40 Hz and one comfort valve ( 17 ″) is present as a pilot-controlled bore.