伺服液压缸位置控制失效问题分析与处理

Analysis and Treatment of Position Control Failure for Servo Cylinder

伺服液压缸是激振试验台液压系统的执行元件,通过激振试验台的上位机软件可以控制伺服液压缸进行手动控制及正弦波、方波、三角波、随机波等信号的幅频控制,设备主要应用于底盘减震类产品的可靠性测试。在某减震器可靠性测试过程中出现伺服液压缸端盖渗油,经拆解更换密封件后,伺服液压缸只能在其行程的两个极限位置运行,位置控制功能失效。通过对激振试验台结构及工作原理分析,从伺服液压缸的LVDT位移传感器有效性、位移传感器相关线路及伺服液压缸结构等方面开展分析排查并定位原因,对LVDT位移传感器损坏的情况,根据差动变压器工作原理,对传感器铁芯进行修复,传感器本体重新安装定位,试验台功能恢复正常。

The servo oil cylinder is the executing component of the hydraulic system of the vibration test bench.Through the upper computer software of the vibration test bench,the servo oil cylinder can be manually controlled and the amplitude frequency control of sine wave,square wave,triangular wave,random wave and other signals can be controlled.The equipment is mainly used for reliability testing of chassis damping products.During the reliability testing of a certain shock absorber,there was oil leakage from the end cover of the servo cylinder.After disassembling and replacing the sealing components,the servo cylinder could only operate at the two extreme positions of its stroke,and the position control function failed.This article analyzes the structure and working principle of the excitation test bench,analyzes and locates the reasons from the effectiveness of the LVDT displacement sensor of the servo oil cylinder,the relevant circuits of the displacement sensor,and the structure of the servo oil cylinder.Based on the working principle of the differential transformer,the sensor core is repaired,the sensor body is reinstalled and positioned,and the function of the test bench is restored to normal.