考虑自旋的高速角接触球轴承油膜刚度计算

摘要

Spinning exists in high-speed transmission support bearings,it can affect oil film thickness of a bearing. The calculation formulas for oil film stiffness of an angular contact ball bearing considering spinning was deduced based on the elastohydrodynamic lubrication (EHL)theory and the method for calculating attitude angle with Darren Bell theory, considering varying of the minimum oil film thickness on the contact points between balls and raceways when spinning exists both at inner and outer raceways.An example was calculated with the derived formulas and the result was compared with that calculated using the minimum oil film thickness empirical formulas proposed by Hamrock-Dowson without considering spinning.The calculation results showed that the spinning angular velocity increases with increase in the rotating speed but decreases with increase in load,the effect of the radial load on spinning is larger and the effect of the axial load is less;the minimum oil film thickness considering spinning is smaller and the oil film stiffness is bigger due to the effects of sliding velocity after considering spinning;so,it is necessary to consider the impact of spinning on bearing stiffness when calculating high-speed transmission shafting vibrations.%针对高速传动装置支撑轴承存在自旋运动且影响轴承油膜刚度问题，基于弹流润滑理论与达朗贝尔原理计算姿态角方法，考虑内外圈滚道同时存在自旋时滚动体与滚道接触处最小油膜厚度变化，推导考虑自旋的角接触球轴承油膜刚度计算公式，并进行实例计算，并将计算结果与利用Hamrock-Dowson的不考虑自旋最小油膜厚度经验公式计算刚度进行对比。计算结果表明，随转速的增大，自旋角速度增大；载荷增大，自旋角速度减小，径向载荷对自旋影响较大，轴向载荷对自旋影响较小；考虑自旋后由于自旋运动影响，其最小油膜厚度变小，油膜刚度变大。高速传动装置轴系振动计算时轴承刚度需考虑自旋影响。