用有限元法对挖掘机工作装置进行瞬态动力学分析,以6 t小型挖掘机工作装置为研究对象,针对斗杆液压缸驱动铲斗撞击地面工况,用压力传感器、位移传感器测试出撞击过程各液压缸工作腔压力和位移变化曲线,以所获各液压缸位移变化曲线和最大理论撞击力为驱动,用动力学仿真软件ADMAS对挖掘机撞击过程进行仿真,得出各铰销点在撞击过程中所承受载荷的变化曲线,采用测试所得各液压缸的驱动力验证仿真结果的准确程度。进一步将各铰销点受力的仿真结果作为工作装置的负载,对工作装置进行瞬态动力学分析,对比仿真计算与应力测试结果表明,对应测点的应力变化趋势基本一致,误差在10%以内,可为结构优化设计提供依据。
By taking a 6-ton small excavator working device as the research object,working device's transient dynamic analysis is studied with finite element method.When bucket hits ground in the driving of stick hydraulic cylinder,the actual working pressures and displacements process of each hydraulic cylinder are measured with pressure and displacement sensors.The forces of articulated points on working equipment can be obtained by means of excavator's kinematics simulation in ADMAS,motions are obtained from hydraulic cylinder's actual displacements and theoretical maximum digging force.In comparison with hydraulic cylinder's actual working pressures,the results of simulation in ADMAS are verified.Under detrimental working conditions,the transient dynamic analysis is conducted for finite element analysis.In comparison with stress test results and simulation calculation results,it is shown that the stress variation trend of corresponding measuring point is basically consistent,and the error is within 10%.The results provide a basis for future structural optimization.