Research on new shock absorber with variable piston volume for automotive

Abstract

Aiming at the problem that the friction heating phenomenon of rigid piston in traditional shock absorber has not been well treated, based on the idea of variable piston volume, a variable piston is invented, and its structure and throttling characteristics are studied. On this basis, a variable piston shock absorber is designed for vehicle. In the variable piston shock absorber, the flow resistance structures and paths of oil flowing through are different under various working conditions. According to the flow equivalent relationship between the choke structures, the pressure difference models at both ends of the choke structures are established, and further integrate into the overall damping force model of the shock absorber. Then, the damping characteristics of the variable piston shock absorber are simulated and analyzed, and the force-displacement characteristics and speed characteristics are verified on a test bench. The simulation and experimental results show that the variable piston shock absorber has good force-displacement and speed characteristics without direct contact and friction on structure, which can meet the requirements of vehicle operation.

Keywords

• flexible piston
• shock absorber
• damping force
• force-displacement characteristic