The Analysis Of Excavator Working Device Hydraulic System

Hydraulic excavator as a kind of fast, efficient construction machinery has been increasing widely used in the modern construction. The hydraulic excavator working device is excavator actuator of digging behavior. The size of the digging force, digging equipment working scope are determined by the hydraulic excavator working device, so the performance of the excavator is directly determined by working device Well-designed hydraulic system of excavator working device has critical influence on the performance.At the same time as uncertainty of digging conditions, that is, the uncertainty of digging force, the pump will be short of oil. In view of this situation,Rexroth has developed a load independent flow distribution system.Load independent flow distribution system embodied advantages especially in the situation of unsaturated flow actuators. In general hydraulic system when flow is insufficient, hydraulic oil will flow into the actuator whose load is small while the actuator whose load is big would get enough oil even stop motion. In the load independent flow distribution system when oil is shortage, the flow oil from the pump outflow comes to different actuator by certain proportion, which can achieve the ability of anti-saturation.With rexroth load independent flow distribution system as the research object, the thesis analyses the difference between load independent flow distribution system and load sensitive system, and get the theory that load independent flow distribution system have he ability of anti-saturation.The characteristics of load independent flow distribution system lies in its design of the multiway valve pressure compensation after throttle, so the paper establishes the mathematical model of multiway valve in order to analyze the working principle, and takes the simulation with simulation software MATLAB/SIMULINK. The simulation analyzes flow distribution characteristics according to the multiway valve and the multiway valve structure parameters on the effect of flow distribution, which provides the basis for the structural parameters of multiway valve design.