Abstract: In order to increase the automation level and test accuracy of the tractor hydraulic hitch system, a test-bench structure of the program was proposed, which used the electro-hydraulic proportional valve for controlling the loading force and verticality during the test. Based on SimulationX software, the hydraulic loading system of the test bench was simulated and analyzed. The results indicate that the adjustment time of target loading force is all less than 0.3 s; the maximum error of the loading force test is about 0.6 kN; and the actual curve and the following curve are basically agreed in the rising phase of loading force. In the simulation process of verticality, the time of the system to reach a steady state at a low initial deviation, intermediate and high initial deviation is within 0.3 and 2.0 s respectively, which verifies the feasibility of the design and provides an efficient test platform for the product development and quality testing of the tractor hydraulic hitch system.

Key words: vehicle engineering, hitch test bench, hydraulic loading, simulation analysis

摘要： 为提高拖拉机液压悬挂系统检测的自动化水平和测试精度，提出了一种应用电液比例阀控制加载力和垂直度的试验台结构方案，基于SimulationX软件对试验台的液压加载系统进行仿真分析。结果表明：目标加载力调节时间均小于0.3 s；加载力跟随试验最大误差约为0.6 kN，并且在跟随加载力上升阶段实际曲线与跟随曲线基本吻合；垂直度仿真过程中，系统在低初始偏差和中、高初始偏差达到稳定状态的时间分别在0.3，2.0 s以内，可见设计方案是可行的，为拖拉机液压悬挂系统的产品开发和质量检测提供了高效的测试平台。

关键词: 车辆工程, 悬挂试验台, 液压加载, 仿真分析