掘进机负载敏感系统油缸速比与回油背压关系的分析

Analysis of Relationship between Hydraulic Cylinder Velocity Ratio and Back Pressure of Road-header Load Sensing Hydraulic System

现在掘进机普遍采用负载敏感液压系统控制,负载敏感系统通常采用压力补偿器进行压力补偿,使换向阀节流点前后压差保持恒定,并始终等于压力补偿器弹簧设定压力。油缸是掘进机主要执行元件,油缸设计中速比的选择直接影响到系统回油背压和活塞杆稳定性。文中从液压系统流量连续性方程入手,忽略一些对精度影响不大的次要因素,获得系统简化模型,从而得到在负载敏感系统中油缸速比与回油背压的函数关系。

Now the load sensing hydraulic system has been applied to the road-header generally. The pressure compensator was used usually to compensate pressure, so as to make the pressure differential around the throttling point at reversing valves remain un- changed, which was always equaled to the setting pressure of the spring in the pressure compensator. Meanwhile the hydraulic cylinder was the major actuating mechanism in road-header, and the back pressure of the system and the piston rod stability were directly influ- enced by the choice of the hydraulic cylinder velocity ratio in design. Started from hydraulic system flow continuity equation and ignored the minor element which had little influence to the precision, the simply model of system was gotten. Therefore the function relationship between hydraulic cylinder velocity ratio and back pressure of the head sensing hvdraulie system is nhtainect