预紧力与装配偏差对航天轴承摩擦力矩的影响研究

针对低速、轻载航天轴承的摩擦力矩，建立了固体润滑航天轴承摩擦力矩的数学模型。结合拟静力学建立轴承受力平衡方程，研究径向装配位置偏差引起钢球受载变化情况，分析了轴向预紧载荷与径向装配位置偏差对航天轴承摩擦力矩的影响规律。研究结果表明：弹性滞后摩擦力矩、微滑动摩擦力矩和自旋摩擦力矩都随着轴向预紧载荷、径向偏载荷增加而增大；在轴向预紧载荷作用下，摩擦力矩组成分量中的弹性滞后摩擦力矩和自旋摩擦力矩增长趋势为下凸，微滑摩擦力矩增长趋势为上凸；而在径向位置偏差引起的径向偏载荷作用下摩擦力矩组成分量增长趋势为上凸；微滑动摩擦力矩和弹性滞后摩擦力矩为航天轴承摩擦力矩的主要组成部分；轴向预紧载荷和径向偏载荷导致摩擦力矩随其增加而增加，其中对差动摩擦力矩的影响作用最为显著，对弹性滞后摩擦力矩的影响次之，对自旋摩擦力矩的影响最弱。

Influences of Preload and Assembly Deviation on Friction Torque of Aerospace Bearing

The variation law of the friction torque is explored for the friction torque of low-speed and light-load aerospace bearing. A mathematical model of friction torque of solid lubricating aerospace bearing is established, and a balance equation of bearing under load is established based on the quasi-state of bearing. The axial preload is due to axial preloading, and the radial partial load is induced by the radial assembly deviation. The situation of ball under loading is analyzed, which is caused by the assembly deviation. The influence law of axial preload and radial position deviation on the friction torque of bearing is obtained. The results show that the elastic hysteresis friction torque, micro-sliding friction torque and self-spin friction torque of bearing increase with the increase in axial preload and radial partial load. Under the axial preload, the increasing trends of elastic hysteresis friction torque and self-spin friction torque in the components of friction torque are convex downward, while the increasing trend of micro-slip friction torque is convex upward. Under the radial partial load, the increasing trend of frictional moment component growth is convex downward. The micro-sliding friction torque and the elastic hysteresis friction torque are the main components of friction torque of aerospace bearing. While the load increases, the friction torque increases. The effect of load on the differential friction torque is the most significant, followed by elastic hysteresis friction torque and self-spin friction torque.