温度和过盈量对轴系接触应力及刚度性能的影响

Influence of temperature and interference on contact stress and stiffness property of the shafting

航天特种装备在轨服役期间故障因素和演化规律是研究航天器可靠性的重要基础方向。精密轴系性能随恶劣空间环境的变化而发生演变。轴承固体润滑膜的接触应力和轴系的刚度性能对于精密轴系精确、可靠运行具有重要意义。以航天机构中驱动单元轴系的成对角接触球轴承为研究对象,考虑环境温度、热致过盈量和轴向载荷,分析了在交变温度作用下轴系的各组件在径向和轴向产生的热变形引起的配合表面配合性质和配合量的变化及成对角接触球轴承预紧特性的变化,提出了数值求解轴承接触应力和轴系刚度变化规律和变化范围的整体思路和分析框架,并进行了算例计算。计算思路具有普遍适用性,计算过程及结果对于驱动单元轴系的结构设计及可靠性验证试验的开展具有指导意义。

The fault and evolution law of the special spacecraft in its orbital service serve as the fundamental basis for making a study on the reliability of spacecrafts. The precision shafting property varies as the harsh space environment changes. Both the contact stress of the bearing solid lubricating film and the stiffness property of the shafting are important for the precise and reliable operation of the precision shafting. Based on the angular contact-ball bearing of the drive-unit shafting in the spacecraft,such factors as ambient temperature, thermal induced interference, and axial load are taken into consideration. An analysis on the shafting components under the alternating temperature is conducted. It shows the change of the mating property on the mating surface and the mating amount caused by the radial and axial thermal deformation, as well as the change of the preload property of the angular contact-ball bearing. The overall idea and the analytical framework of numerically solving the evolution law and the variation range of contact stress and shafting stiffness are proposed. Based on this, some calculations are conducted.The calculation idea can be applied in a wide range of fields. The calculation process and results provide guidance for both the structural design of the drive-unit shafting and the experiment of reliability verification.