基于有限元仿真的行星滚柱丝杠动态特性分析

Dynamic Characteristic Analysis Based on Finite Element Simulation for Planetary Roller Screw

通过CATIA对行星滚柱丝杠机构进行三维建模,采用有限元仿真技术分析了机构的6阶固有频率,得到了各阶模态主振型图,分别研究了支承方式、螺母工作位置、离心力等因素对机构固有频率的影响。研究表明,采用两端固定支承的行星滚柱丝杠固有频率较高,适宜在高速工况下使用;螺母工作行程越大,机构整体抗振性能越低,承受的极限转速也越小;机构高速运转时产生的离心力将导致零部件的变形增大,降低其传动精度,在具有高精度要求的工况下,不宜采用过高转速。

Three-dimensional model of planetary roller screw is built by the CATIA software .Through the finite element simulation , the planetary roller screw＇s six order inherent frequencies are calculated and vibration shape diagrams are obtained .The influences caused by different supporting patterns ,working position of nut and centrifugal force are discussed .Through these analysis ,it can be obtained that the planetary roller screw has higher inherent frequencies using two ends fixed supporting ,the mechanism can be used in high-speed working condition for the best ;the longer of nut＇s working stroke , the lower of mechanism＇s anti-vibration performance ;the centrifugal force during rotating can increase the deformation of parts , which can decrease the transmission accuracy of planetary roller screw ,and in the case of high precision ,it is inappropriate to adopt an exorbitant speed .