RV减速器有限元动态仿真与接触疲劳强度设计

Finite-element dynamic simulation and design of contact fatigue strength for RV reducer

为计算RV减速器摆线轮齿面接触疲劳强度,分析RV减速器摆线针轮传动的动态啮合受力过程和接触疲劳发生机理,应用有限元软件ANSYS建立摆线针轮传动有限元模型。在该模型中,自动建立了多点约束方程模拟轴承连接,并利用刚性梁单元以桁架的方式连接成行星架。通过有限元动态仿真,得到摆线轮齿面最大接触应力随曲柄轴转角变化的曲线,估算出摆线轮齿面接触疲劳寿命。结果表明,针对RV减速器摆线针轮传动的有限元建模方法具有可行性。由于摆线轮轮辐变形的影响,摆线轮齿面最大接触应力仿真计算结果与理论计算结果有一定差异,验证了模拟轴承的仿真误差,估算出的接触疲劳寿命接近于无限寿命。

In order to calculate the contact fatigue strength of the RV reducer’s cycloid gear tooth surface,the process of dynamic meshing force and the mechanism of contact fatigue in the RV reducer’s cycloid drive are analyzed.The finite-element software ANSYS is adopted to model the cycloid drive.In this model,the multi-point constraint equation is automatically set up to simulate the bearing connection.The planetary frame is modeled by means of rigid beam element and truss connection.The curve which indicates that the maximum contact stress of the cycloid gear tooth surface changes with the crankshaft rotation angle is identified with the aid of the finite-element dynamic simulation.Thus,the contact-fatigue life of the cycloid gear tooth surface is estimated.The results show that the finite-element dynamic modeling method for the RV reducer’s cycloid drive is feasible,and the maximum contact stress is different from the theoretical result,which is mainly affected by the deformation of the cycloid’s wheel spoke.Besides,the simulation error of the simulated bearing is verified;the contact-fatigue life which has been estimated is close to the infinite life.