双螺母定位预紧滚珠丝杠副轴向接触刚度分析  

Axial Contact Stiffness Analysis of Position Preloaded Ball Screw Mechanism

作　　者：胡建忠[1] 王民[1] 高相胜[1] 昝涛[1] 

机构地区：[1]北京工业大学先进制造技术北京市重点实验室,北京100124

出　　处：《机械工程学报》2014年第7期60-69,共10页Journal of Mechanical Engineering

基　　金：国家科技重大专项(2012ZX04010021-001-004);北京市自然科学基金暨北京市教委科技计划重点(KZ201410005010);北京市自然科学基金(312205);国家自然科学基金青年基金(51105010)资助项目

摘　　要：提出一种新的滚珠丝杠副刚度分析方法,建立螺母所受轴向力与滚道正压力之间的关系,分析滚道接触点处的法向变形与螺母相对于丝杠的轴向位移之间的关系。综合考虑滚珠、螺母和丝杠滚道的几何参数,将接触角、公称半径以及螺旋升角作为未知量,建立滚珠丝杠副接触角模型。在此基础上,根据Hertzian接触理论建立了滚珠丝杠副的轴向刚度模型,该模型综合考虑了接触角的变化与滚道正压力之间的耦合关系。根据所建立的刚度模型分别研究了单螺母滚珠丝杠副和双螺母定位预紧滚珠丝杠副的刚度特性。研究结果表明,对于几何参数相同的滚珠丝杠副,在外加轴向力较小时双螺母预紧滚珠丝杠副的刚度明显大于单螺母滚珠丝杠副,随着外加轴向力的增大它们的刚度值逐渐趋近,最后达到相同;双螺母定位预紧滚珠丝杠副的预紧力越大,初始刚度值越大。An approach to stiffness analysis of ball screw mechanism is proposed, and the relationship between the axial force applied on the nut and the pressure on the raceway of nut or screw is obtained by force analysis. The relationship between the axial displacement of nut with respect to screw and the normal elastic approach between the ball and raceway at the contact point is analyzed. The model of the contact angle of ball screw mechanism is established considering the geometric parameter of the ball and the raceway of nut and screw. On this basis, the model of the axial stiffness of the ball screw mechanism is established according to the theory of Hertzian contact, in which the coupling relationship between the pressure of the raceway and the variation of the contact angle is considered. According to the model, the stiffness characteristic of the single nut ball screw mechanism and the preloaded double nut ball screw mechanism is studied. The result shows that the stiffness of the preloaded ball screw mechanism is larger than the stiffness of the single nut ball screw mechanism when the applied axial load is small, and the difference of stiffness between them reduced as the increasing of applied axial load. And the stiffness of preloaded ball screw mechanism increase with the preload as the applied axial load is small.

关 键 词：接触刚度 滚珠丝杠副 预紧力 接触角 赫兹接触理论 

分 类 号：TH132[机械工程—机械制造及自动化]