A Vibration-Based Measurement Method for Dynamic Characteristic of Solenoid Switching Valve

Solenoid switching valve (SSV) is the central control part of digital hydraulic system (DHS). Dynamic performance is the most important feature of SSV because it guarantees the response time and control effect of DHS. However, due to the compact structure and small size of SSV, the traditional displacement test method is hardly to obtain its dynamic performance directly, which leads to the dynamic performance accurate evaluation of the SSV becoming a challenge. In this article, a vibration-based measurement method (VMM) is come up with to detect the switching behaviors of the SSV. A valve body vibration model during the switching process of SSV is established, its vibration law is revealed, the relationship between valve body vibration characteristic and operation states of SSV is obtained, and the real-time high-precision detecting of dynamic performance of the SSV is finally realized. In order to show the superiority of VMM, different dynamic behaviors of SSV have been measured, and a laser displacement sensor (LDS) has been used for comparison and verification. Experimental results illustrate that the VMM is able to measure the dynamic performance of SSV without changing its internal structure and destroying the original dynamic behaviors. Compared with the LDS, the results of VMM are more reliable, the opening time of SSV is shortened by 12.6% and the closing time is shortened by 13.9%. What is more, the VMM can also achieve real-time measurement under high-frequency continuous switching applications. Therefore, the VMM has higher precision, stronger reliability, better real-time ability, and more economical benefits so that it has huge potential in many engineering applications.