Comparison of Operating Characteristics Between Symmetrical/Asymmetric Pump-controlled Asymmetric Cylinder Systems Under Four-quadrant Conditions
When the closed pump control system drives widely used asymmetric hydraulic cylinders,it needs to increase the complex large flow compensation circuit to compensate for the asymmetric flow caused by the difference in the area of the two chambers of the asymmetric cylinder.When the load capacity of the excavator is low,the oil replenishment chamber and the control chamber will be frequently switched,the replenishment valve opening state is unstable,it is difficult to match the real-time high-flow oil compensation.The frequent flow of large-flow oil causes speed and pressure fluctuations,generating hydraulic shock and affecting the smoothness of the system.A scheme for an asymmetric pump-controlled asymmetric hydraulic cylinder system was proposed,which utilizes the structure of the asymmetric pump to match the asymmetric flow rate.Construct simulation models of asymmetric pump-controlled and symmetric pump-controlled bucket arm excavators based on typical four-quadrant conditions of operating bucket rod,and compare their operating characteristics.The results show that the proposed system can balance the asymmetric flow without large flow compensation,eliminating the speed and pressure fluctuations,and it is found that the four-quadrant condition switching and the generation of speed and pressure fluctuations are not synchronized.
asymmetric pumppressure fluctuationfour-quadrant conditionsasymmetric cylinderpump-controlled asymmetric cylinderexcavator bucket rod
万方数据
维普
