Patent ID: 7637516

Claim:
A suspension system for a vehicle, comprising: (a) four suspension cylinders respectively corresponding to a front left wheel, a front right wheel, a rear left wheel and a rear right wheel of the vehicle and having respective hydraulic chambers; and (b) a control cylinder having a cylinder housing and a piston assembly which is fluid-tightly and slidably fitted in said cylinder housing, the piston assembly including a first piston, a second piston and a third piston arranged in series with each other in an axial direction of said control cylinder and fixedly connected to each other, wherein: said first and third pistons have a same diameter while a diameter of said second piston is different from the diameter of said first and third pistons, said cylinder housing and said piston assembly define four groups of hydraulic chambers which consists of: one hydraulic chamber formed on one side of said first piston which is remote from said second piston, at least one hydraulic chamber formed between said first and second pistons, at least one hydraulic chamber formed between said second and third pistons, and one hydraulic chamber formed on one side of said third piston which is remote from said second piston, at least one hydraulic chamber belonging to each of said four groups of hydraulic chambers is connected to a corresponding one of said four suspension cylinders, and between said first and third pistons there are no hydraulic chambers, which are not connected to any of said four hydraulic chambers of said four suspension cylinders.