Patent ID: 6494442
Filing Date: 2002-12-17
Classification: B60G,F16F,Y10S

Abstract:
A self-pumping hydropneumatic spring strut with internal leveling for a motor vehicle, comprising:a working cylinder; a working piston arranged in the working cylinder defining a high pressure chamber and a low pressure chamber, the piston and the working cylinder defining at least one gas cushion which acts as a spring, the high pressure chamber being connected to a working space, wherein a bleed opening forms a flow connection between the working space of the high pressure chamber and the low pressure chamber and can be closed as a function of the position of the piston in the working cylinder; a hollow piston rod moveably arranged in the working cylinder and connected to the piston and forming a piston pump which is driven by suspension movements, whereby oil is pumped out of the low pressure chamber into the working space connected to the high pressure chamber; and an actuator operatively arranged to vertically displace the spring strut, the actuator being operative for displacing the spring strut to a plurality of displacement distances independent of axial movement of the spring strut due to vehicle loading.