Liquid spring having improved damper valve structure

Abstract

A vehicular suspension system includes a liquid spring operatively interconnected between a vehicle frame and an associated wheel assembly to provide resistive spring and damping forces in response to relative vertical displacement between the frame and wheel assembly. The liquid spring includes a cylinder secured to the vehicle frame and having a compressible liquid-filled internal chamber in which a piston structure is reciprocally disposed and divides the chamber into bounce and rebound chambers. A rod is slidably and sealinqly carried by the cylinder for axial movement into and out of the chamber, the rod having an inner end anchored to the piston structure, and an outer end portion extending outwardly from the cylinder and secured to the wheel assembly. A flow passage extends through the piston and intercommunicates the bounce and rebound subchambers. An intermediate portion of the flow passage is defined by a valve chamber disposed within the piston structure and captively retaining a movable damper valve. The damper valve is operable to restrict liquid flow through the piston passage in a manner providing greater resistance to liquid flow in one direction between the bounce and rebound subchambers than in the other direction in response to axial rod movement into and out of the cylinder chamber. The directional liquid flow restriction differential of the damper valve may be conveniently reversed simply by reversing the orientation of the damper valve within the internal piston structure valve chamber.