误差-磨损-温度变化耦合的行星滚柱丝杠副载荷分布

Load Distribution of Planetary Roller Screw Mechanism with Error,Thread Wear and Temperature Change

为了揭示误差-磨损-温度变化耦合作用对行星滚柱丝杠副(PRSM)螺纹载荷分布的影响规律,基于变形协调关系,建立了计及误差、磨损和温度变化的PRSM载荷分布模型。通过与现有有限元模型和弹簧模型对比,最大相对误差为8.36%,表明所建模型正确且可用于载荷分布规律研究。在此基础上,研究了无误差、含误差和磨损、以及含温度变化的载荷分布规律。结果表明,误差是导致载荷不均和波动的主因;磨损加剧了载荷分布不均及波动;温度变化造成载荷分布规律发生变化并以中间螺纹为基准呈近似对称分布,且当温度变化达到80℃时,最大载荷增加了9.2%,可见温度变化会增大单个螺纹承载量并导致过载风险;温度变化为40℃时,载荷分布相对更加均匀,控制温度变化可作为改善PRSM载荷分布的有效方法。

In order to reveal the coupling effect of error, thread wear and temperature change on load distribution of planetary roller screw mechanism （PRSM） , a load distribution model of PRSM with error, thread wear and temper- ature change finite elemen is developed based on deformation coordination relationship in this paper. Compared with the existing t model and the spring model, the maximum relative error is 8.36%, which verifies the correctness of the presented model and can be used to study the load distribution. Furthermore, the load distribution trend without errors, with errors and wear, as well as temperature change is studied. The results indicated that the error is the main factor, which leads to load uneven and fluctuation, wear intensifies the load uneven and fluctuation, and tem- perature change leads to the change of load distribution and shows symmetric distribution in the middle of the thread as reference. The maximum load increases 9.2% when temperature change is 80~C, therefore, the temperature change leads to load increase of some thread, which will further intensifies overload risk. Besides, the load distribu- tion is relative even when temperature change is 40℃, and the control of temperature change can be regard as a method to improve load distribution of PRSM.