负载口独立双阀芯电液阀的结构优化

Structure Optimization of Load Port Independent Double Spool Electro-hydraulic Valves

为研究负载口独立电液阀系统结构参数对主阀微动特性的影响,基于功率键合图理论,建立了电液阀系统状态空间方程,采用一阶灵敏度方法,分析了系统参数对主阀微动特性的影响规律;反馈控制系统的先导结构参数对主阀运动特性至关重要,以系统不产生自激振荡与最佳阻尼比为约束条件,对先导级死区宽度、阀口形式、进回油阀口匹配系数进行研究,实现了先导级主级最佳匹配。研究结果表明,对主阀微动特性影响较大的因素依次为主阀芯所受摩擦力、非弹簧控制腔液容、导阀入口到主阀控制腔管路液容(非弹簧侧)、主阀弹簧预紧力,对上述影响参数进行优化的同时,当导阀死区宽度δ≤0.25 mm,阀口形式为U形阀口,进回油阀口匹配系数η=0.53时,系统综合性能可得到有效提高。

In order to study the influences of load port independent electro-hydraulic valve system parameters on the main valve fretting characteristics,a state space equation of electro-hydraulic valve systems was established based on the power bond graph theory,and the first-order sensitivity method was used to analyze the influences of system parameters on the main valve fretting characteristics.The pilot structure parameters of the feedback control systems were very important to the movement characteristics of the main valve,the dead zone width of the pilot stage,the form of the valve port and the matching coefficient of the inlet and return oil valve port were studied under the constraint conditions of no self-excited oscillation and the best damping ratio,the best match between the lead stage and the main stage was achieved.The results show that the main valve fretting characteristics are greatly affected by the friction force of the main valve core,the liquid capacity of the non-spring control chamber,the liquid capacity of the pipeline from the pilot valve inlet to the main valve control chamber(non-spring side)and the preload force of the main valve spring.While optimizing the above influencing parameters,the dead zone width of the pilot valveδ≤0.25 mm,the U-shaped valve port,and the matching coefficient of the inlet and return oil valve portsη=0.53,the overall performance of the system is effectively improved.