Dynamic Modeling And Consumption Analysis Of Wheel Loader Working Device

Loader is the largest sales volume of the construction machinery. With the increasing demand of the user and the rapid development of hydraulic technology, the demand of the quality, efficient and energy saving of the loader is raising. The traditional research and development cost of the wheel loader is high, and the development cycle is also too long. Studying the working device of the wheel loader, this paper builds the hydraulic and machinery model of the working device based on Simulation X. This paper verified the correctness of the simulation model. The correct simulation model can be used in failure analysis, system improvement and energy saving analysis of the wheel loader hydraulic system.On the basis of the loader hydraulic system, this paper analyzed the pump, multi-way valve, hydraulic cylinder of the system and the structure of composition components and specified the circulate way of the oil. Building the pressure flow equation of the hydraulic element separately, the overflow area and hydraulic diameter of the reversing valve is calculated through MATLAB. The approaches to build the model is as follows:Build the model of the hydraulic element separately, input the parameter of the pump and the characteristic parameter of the relief valve, import the reverse-turning six-bar linkage from CATIA and set the space coordinate. To connect the element model will obtain the whole system model. After setting the simulation environment and initial valve of the element, the simulation should be run.Working device is tested on the typical working condition, and characteristics of the working device in intermediate and idle condition are analyzed. The simulation environment should be set according to the test environment and the simulation time should be set as same as the control signal of the multi-way valve in the test. Through the comparison of the simulation and test result, the difference is approximately in3%, so the model is proved to be corrected. Because of many factors affecting the hydraulic system performance and the invisible relationship between the hydraulic element and flow, the testing curve is needed to understand the internal state of the hydraulic system. The test is a waste of time and cost, for it needs a lot of equipments or hydraulic elements. With the right simulation model, the loader working device should be analyzed based on software to view the feasibility.In the last chapter the energy loss in intermediate speed and idle condition analyzed and calculated. The energy loss of the pump is obtained through the power curve of the pump. The simulation results show that the pressure overflow loss is37.5%which is the most important form of energy loss in the entire work cycle. The simulation model proved the energy saving of the common energy saving system.This issue built the whole model of the wheel loader working device, and proved the correctness of the model through the test. The system energy consumption is analyzed through the curve, and the energy saving system model is built. The simulation model can be used to do test analysis in virtual, and reduced the complexity of the experiment. It is useful for new product improvement, energy saving and do innovate research on the wheel loader.