预紧及尺寸误差对角接触球轴承-转子振动性能的影响

Effects of Axial Preload Displacement and Size Errors of Balls and Raceways on the Vibration Properties of Angular Ball Bearing Rotor System

通过对角接触球轴承受力分析,建立了单个滚子受力变形、滚动轴承整体受力变形、轴承承载区范围与预紧量关系的数学表达式,并在此基础上给出了考虑滚子、滚道尺寸误差,保证轴承滚子与内、外滚道全接触时的最小轴向预紧量的计算公式,建立了刚度和阻尼的计算模型。以7012C型角接触球轴承支承的Jeffcott转子为算例,计算研究了预紧量和尺寸误差对转子的振动性能的影响,计算了在不同预紧量下、有误差和无误差时的轴承振动频谱图,计算了预紧量变化对最大振幅和临界转速的影响规律曲线,并对计算结果进行了理论分析。

By geometric and mechanics analysis on the angular contact ball bearing, the calculation models of single ball deformation, bearing deformation, load zone and axial preload displacement are established, and the model for calculating the minimum preload for ensuring all balls contact with raceways is established with considering size errors of balls and raceways. The models for calculating the stiffness and damping of bearing are developed. Taking the Jeffcott rotor supported by the angular ball bearing 7012C as research example and by numerical simulation, the influences of preload and size error on the rotor vibration properties are investigated in detail. The vibration spectrum diagram and a set of curves about the maximum amplitude and critical speed related to the axial preload displacement are obtained and analyzed with and without considering size errors of roller and raceway.