Patent ID: 7497452

Claim:
A suspension system for damping motion of a first member with respect to a second member on a vehicle, said suspension system comprising: a tank for holding a fluid; a cylinder assembly connected to the first member and the second member and comprising a cylinder, in which a piston defines a first chamber and a second chamber, and a shaft connected to the piston and having a surface exposed to pressure within a third chamber of the cylinder; a first accumulator and a second accumulator; a first accumulator valve controlling flow of fluid between the first chamber and the first accumulator; a second accumulator valve controlling flow of fluid between the second chamber and the second accumulator; and a damping valve having a first position which connects the second chamber to the third chamber and a second position which connects the third chamber to the tank, wherein selection of the first position and the second position changes stiffness of the suspension system and is made in response to force acting on the suspension system.