含间隙3-CPaR&R_(1)R_(2)混联机构磨损特性分析

Wear performance analysis of 3-CPaR&R_(1)R_(2) hybrid mechanism with joint clearance

为研究不同物理条件下间隙关节磨损特性,本文以3-CPaR&R_(1)R_(2)混联机构为研究对象并在转动副中考虑间隙的存在,运用Flores接触力模型及修正Coulomb摩擦模型分别建立关节元素间接触点法向接触力及切向接触力模型,关节润滑力则通过Sommerfeld润滑条件下无限长轴颈-轴承的润滑力模型建立,最终运用拉格朗日方程建立了考虑转动副间隙及关节润滑的动力学数值仿真模型,通过Archard磨损模型分析不同的物理参数对于含间隙关节磨损预测的影响并对比研究有无润滑条件下关节磨损特性。研究结果表明:较高的驱动速度可使间隙磨损相对均匀,但会使磨损深度增加;间隙尺寸对于磨损深度影响较小,但间隙尺寸的增加仍会使磨损深度增加;关节润滑可使间隙关节磨损深度显著减小。

To examine joint wear under different physical parameters,the 3-CPaR&R_(1)R_(2) hybrid mechanism is examined in this study,considering the clearance in revolute pairs.The normal force model and tangential contact force model between joint elements are established based on the Flores contact model and modified Coulomb friction model,respectively.The lubrication force model of joints is established based on the lubrication model of the infinitely long journal bearing under Sommerfeld lubrication conditions.Finally,the dynamic numerical simulation model of the 3-CPaR&R_(1)R_(2) hybrid mechanism is established using the Lagrange equation,considering the revolute pair clearance and joint lubrication.The effects of different physical parameters on the wear prediction of joints are analyzed based on the Archard wear model,and a comparative study of the wear performance of joints with and without lubrication is conducted.The results show that a high driving velocity can make the wear relatively uniform but increase the wear depth.Moreover,the clearance size has little effect on joint wear,but an increase in clearance size can increase the wear depth.Joint lubrication can significantly reduce the joint wear depth.