负载敏感多路阀LS卸荷油路特性分析

Characteristic Analysis of LS Unloading Loop in the Load Sensing Multi-way Valve

负载敏感液压系统中,为防止多路阀处于中位时LS反馈油路困油导致系统憋压,通常需对多路阀处于中位时的LS反馈油路进行回油卸荷。分析4种不同负载敏感多路阀及系统LS中位卸荷油路的工作原理及特性。并以起重机卷扬起升系统为研究对象,理论分析了LS反馈油路为固定阻尼孔卸荷形式的多路阀负载敏感系统流量和压力特性,并进行了仿真和试验验证。

In the load-sensing(LS)hydraulic system,the LS feedback loop needs to return oil to tank and unload in the neutral position of the multi-way valve,for avoiding the pressure increase caused by oil trapped in the LS circuit.The working mechanisms and characteristics of the LS unloading loop for four different load-sensing multi-way valves in the neutral position were analyzed.The crane hoisting system was taken as the experimental subject.The flow and pressure characteristics of the load-sensing multi-way valve and system with LS feedback oil unloaded in the form of a fixed orifice were theoretically analyzed,simulation and experimental verification was performed.