陶瓷轴承电主轴的模态分析及其动态性能实验

Model Analysis and Dynamic Characteristic Experiment of the Ceramic Bearing Motorized Spindle

目的通过对实验室高速精密磨床用陶瓷轴承电主轴的动态特性的研究,验证电主轴结构设计的合理性.方法在Ansys中建立了相应的轴承-主轴系统三维有限元模型,采用了Subspace模态提取法对主轴部件进行模态分析,计算主轴前5阶固有频率、振型和临界转速,并利用锤击法对陶瓷轴承电主轴进行动态响应实验.结果Ansys的模态分析法得出的固有频率与动态响应实验得出的频率基本一致,主轴工作转速远离其临界转速,能有效避开共振区,保证了磨床的磨削精度.结论通过模态分析法,可以看出Ansys对电主轴的动态仿真和计算有一定的指导意义,也为下一步的谐响应分析打下基础.

This paper analysed the dynamic characteristics of the ceramic bearing motorized spindle used in the grinder of the laboratory, and the result verified the rationality of the design structure of the motorized spindle, a 3D FEM of bearing - spindle system was built in Ansys, calculated the first five sets natural frequency, vibration mode and limited speed by the method of Subspace, and did dynamic response experiment with the method of hammer excitation. Natural frequency resulted from modal analysis method of Ansys was basically identical to frequency resulted from dynamic response experiment, the working speed of spindle was far away from its limited rotate speed, it could avoid the region of sympathetic vibrations effectively, guaranteed the grinding precision of the grinder, based on the method of modal analysis, it can be concluded that Ansys had directive sense to dynamic simulation and calculation of motorized spindle, and the research laid a foundation for the harmonic response analysis of motorized spindle in the next step.