Analysis of patents of damping force adjustable hydraulic shock absorber
                                                 YANG Likang1, DU Jiaxin1, ZHOU Anjiang1, WANG Songfeng2
（1.School of Mechanical and Automotive Engineering, Zhejiang University of Science and Technology,Hangzhou 310023, China; 2.Tmax(Hangzhou)Technology Co.,Ltd., Hangzhou 311401, China）

Abstract: Aiming at developing a new model of damping force adjusting mechanism of a damping force adjustable hydraulic shock absorber, the arrangement forms of the adjusting mechanism were analyzed, and the operating principles were summarized according to the technical details of the existing patents. The adjusting mechanisms were sorted into several kinds basing on the distinctions of the operating principles and arrangement forms in different patents, typical structures of different adjusting mechanisms were exemplified and analyzed. Basing on the structure of the regulating mechanism, combining with the manufacturing process and using environment, the practicability, reliability and economic performance of different types of regulators were compared and analyzed. The results indicate that the rodtype adjusting mechanism is suitable for the situation of small installation space, low damping force value with reasonable reliability and cost while the tubetype adjusting mechanism is appropriate for the scene where the installation space is abundant, the damping force value is large, and the demand of reliability is higher.

Key words: automotive suspension; hydraulic shock absorber; damping adjusting mechanism; patent