Analysis of the Vertical Stiffness of Rolling Guide that Involves the ElasticDeformation of Carriage Skirt
Analysis of the Vertical Stiffness of Rolling Guide that Involves the ElasticDeformation of Carriage Skirt
复制标题
DOI：
10.2174/1874155x01509010726
复制
发表时间：
2015-09
期刊：
影响因子：
--
通讯作者：
Li Jinfeng;Wang Liping;Guan Liwen
中科院分区：
文献类型：
--
作者：
Li Jinfeng;Wang Liping;Guan Liwen
静刚度是衡量滚动导轨性能的重要指标，直接影响到数控机床的刚度和精度。预加载滚动导轨后，在车厢裙部产生向外弹性变形，导致滚动导轨静刚度降低。因此，当车架被视为刚体时，数值计算结果与实验结果之间存在较大的误差。本文提出了一种考虑车厢裙板弹性变形的滚动导轨垂直刚度的解析估算方法。利用赫兹接触理论建立了滚动导轨在载荷作用下的接触弹性变形模型，并在忽略裙板弹性变形的情况下，计算了滚动导轨表面垂直刚度的数值结果。给出了车厢裙部变形的有限元计算方法，并通过拟合调整得到了车厢裙部变形与接触力之间的数值关系。在此基础上，建立了考虑弹性接触变形和车厢裙板变形的分析模型，提出了一种通用的竖向刚度计算方法。试验结果表明，考虑车厢裙部变形的竖向刚度数值计算结果与试验结果吻合较好，相对误差不超过6.5%。
Static stiffness is an important indicator of the performance of a rolling guide, having direct influence on the stiffness and precision of computer numerically controlled (CNC) machine tools. After preloading the rolling guide, an outward elastic deformation is generated at the carriage skirt, which leads to a decrease in the static stiffness of the rolling guide. Therefore, there would be relatively large errors between the numerical results and the experimental results when the carriage is considered as a rigid body. In this paper, an analytical method for estimating the vertical stiffness of rolling guide was proposed, which took into account the elastic deformation in the carriage skirt. The contact elastic deformation model under loads was given using Hertz's contact theory, from which the numerical results for the vertical stiffness of the surface of the rolling guide was calculated when the elastic deformation in the carriage skirt was ignored. The calculation method for the carriage skirt deformation was given using the finite element method, from which the numerical relationship between the deformation and the contact force was obtained after fitting adjustment. An analytical model was therefore established and took into account the elastic contact deformation and the carriage skirt deformation, and a universal calculation method was proposed for vertical stiffness. Experimental results show that compared to those not involving the deformation, the numerical results for vertical stiffness involving the carriage skirt deformation matched more closely with the experimental results, with relative errors no greater than 6.5%.