动压气浮轴承锁紧螺母装配应力分析与改进  

Assembly Stress Analysis and Improvement on Locknut of Gas-dynamic Bearing

作　　者：张翰明 郝永勤 谭映戈 朱志刚[1] 孙亚朋 ZHANG Han-ming;HAO Yong-qin;TAN Ying-ge;ZHU Zhi-gang;SUN Ya-peng(Beijing Institute of Aerospace Control Devices,Beijing 100039)

机构地区：[1]北京航天控制仪器研究所,北京100039

出　　处：《导航与控制》2021年第5期128-136,共9页Navigation and Control

基　　金：国家自然科学基金(编号:U1937603)。

摘　　要：半球型动压气浮轴承应用于微小型陀螺电机,具有精度高、寿命长、功耗小、对中性好等特点,但是此类轴承的润滑层厚度仅微米级,因此对零件加工和装配精度要求很高。生产中发现装配应力分布不均会导致半球零件发生变形,降低工作可靠性。针对上述问题,首先通过建立螺纹连接简化模型计算半球预紧后受到的预紧力。然后利用ANSYS Workbench有限元软件仿真预紧力作用下半球轮廓面的圆度变化,发现半球受到743.49N预紧力后球面圆度下降0.05μm,并进一步通过圆度测量实验验证了仿真结果。最后,提出了一种改进锁紧螺母结构减小圆度变化的方案,改进后在相同预紧力作用下,球面圆周变形分布更加均匀,轴承工作可靠性得到明显提高。Hemispherical gas-dynamic bearing is used in micro-miniature gyroscope motor, which has the characteristics of high-precision, long-life, low-power consumption and good coaxial. However, the thickness of lubricating layer of this kind of bearing is only micron level, so it has high requirements on machining and assembling accuracy. It has been found in production that uneven distribution of assembly stress could lead to the deformation of hemispherical parts and reduce the working reliability. To solve this problem, a simplified model of threaded connection is established firstly to calculate preload value after hemisphere is preloaded by locknut. Then, the ANSYS Workbench finite element software is used to simulate variation of roundness on hemisphere. It is found that the roundness declines 0.05μm with 743.49 N preload, and the simulation result is contrastively verified with measuring experiments. Finally, a scheme to improve the locknut structure and reduce the roundness change is proposed. After the improvement, under the same preload, the spherical circumferential deformation distribution is more uniform, and the working reliability of the bearing is significantly improved.

关 键 词：动压轴承 预紧力 ANSYS 应变 圆度 

分 类 号：TM303.5[电气工程—电机]