预载荷在线控制电主轴振动特性的试验研究

Experimental Study on Preload Online Control of Electric Spindle Vibration

为实现对电主轴振动特性进行主动控制并改善其运行过程中的动态性能,利用所研制的预载荷可调整电主轴,搭建了电主轴振动特性在线控制试验平台,基于该平台,开展了轴承预载荷在线控制条件下电主轴振动特性的试验研究。试验结果表明:电主轴转子系统的1~5阶固有频率随轴承预载荷的增大而提高,其中2阶固有频率受轴承预载荷的影响最大;在同一转速条件下,电主轴本体的振动随轴承预载荷的增大而减小,轴心轨迹半径也呈现出减小的趋势;在同一预载荷条件下,电主轴本体的振动随转速升高呈增大的趋势,但轴心轨迹半径略有减小的趋势。这表明,采用预载荷在线控制技术可以有效控制电主轴的振动特性,为发展智能电主轴技术提供条件。

In order to realize the active control of the vibration characteristics of the electric spindle and im-prove the dynamic performance during its operation,a test platform for the vibration performance of the electric spindle is established by using the electric spindle with adjustable preload.Based on the platform,the experimental study of the vibration characteristics of the electric spindle under different bearing preload conditions is carried out.The results show that:the first-order to fifth-order natural frequencies of the electric spindle system increase with the increasing of the bearing preload,and the second-order natural frequency is most affected by the bearing preload;under the same speed condition,the vibration of the main body of the electric spindle decreases with the increasing of the bearing preload,and the radius of the orbit of shaft centerline also shows a decreasing trend;under the same preload condition,the vibration of the electric spindle increases with the increasing of the rotation speed,but the radius of the orbit of shaft centerline slightly decreases.Furthermore,it is shown that the preload online adjustment technology can effectively control the vibration characteristics of the electric spindle and provide conditions for the development of the intelligent electric spindle technology.