2(3PUS+S)型并联机构驱动部件刚度特性分析

针对2(3PUS+S)型并联机构进给驱动部件,提出并研究了对其刚度分析的新思路和方法,该并联机构以直线模组作为驱动部件,整体刚度主要由滚珠丝杠的刚度、滚珠丝杠副的刚度以及支承轴承的刚度这三大部分组成。计算时先将系统进行简化,同时考虑到滚珠丝杠副在工作状态下滚珠和滚道在面接触点处的弹性变形,以及滚珠丝杠副和支承轴承中结合部的变形,结合理论力学和赫兹接触理论相关理论知识,对滚珠丝杠刚度、滚珠丝杠副轴向刚度以及支撑轴承轴向刚度分别推导求取,最终整合得到整个系统的刚度。此方法概念明确,计算简便,研究结果对此并联机构稳定工作以及动态性能的优化提供了依据。

Stiffness Analysis of the Drive Components for a 2(3PUS+S) Parallel Mechanism

In view of the feed drive components of 2(3PUS+S) parallel mechanism, a new idea and method for the stiffness analysis are proposed and studied.The parallel mechanism was used of a linear module as the drive component, and the overall stiffness was mainly determined by the stiffness of the ball screw. The three components of the rigidity of the ball screw pair and the stiffness of the bearing support were simplified in the calculation, taking into account the elastic deformation of the ball and the raceway at the surface contact point under the working condition of the ball screw pair, and the deformation of the joint between the ball screw and the bearing, combined with the theoretical knowledge of theoretical mechanics and Hertz contact theory, the ball screw stiffness, the axial stiffness of the ball screw and the axial stiffness of the bearing were derived separately, and finally integrated to get the stiffness of the entire system. The method is clear in concept and simple in calculation. The research results provide a basis for the stable operation of the parallel mechanism and the optimization of dynamic performance.