Multi-body Dynamics Simulation And Optimization Of High Speed Spindle

High-speed machining technology has become the development direction of metal processing due to its unique features of advancement,extensiveness,practicability,integration,systemicity and dynamics.To achieve high-speed machining,high-speed machining centers are essential infrastructure.The high-speed electric spindle as the core functional component of the high-speed machining center,its structure and performance directly determine the overall performance of the high-speed machining center.Therefore,the research and optimization of the structure and performance of the high-speed spindle is of great significance for improving the structure of the high-speed machining center and improving the machining accuracy.The main moving parts of the high-speed spindle system are the shaft and the bearing.In order to optimize the performance of the high-speed spindle system,the system consisting of the shaft and the angular contact ball bearing is selected as the research object,and the system vibration is reduced to optimize the target and simulate.Firstly,the multi-body dynamics theory analysis of the shaft and bearing is carried out,and the dynamic characteristics under high-speed motion are analyzed.Then the virtual prototype model of the high-speed spindle system is jointly established by software such as SolidWorks and ADAMS.Perform modal analysis on the shaft to obtain the first-order critical speed of the shaft,and determine the vibration test point of the simulation experiment at the overhang of the shaft;The modal analysis of the bearing cage is carried out to obtain the characteristics of the main mode of the cage in various frequency ranges,which has certain reference value for the structural dynamic design of the bearing and equipment fault diagnosis.Finally,the whole model is simulated,and the bearing tightness and the number of rolling elements are taken as variables.Under the experimental conditions of high speed and light load,the conclusion is drawn:1.Different bearing tightness has a greater influence on the vibration of the spindle system.The tightness and vibration displacement values have an approximate linear decreasing relationship in the whole simulation interval,that is,the greater the bearing tightness,the smaller the vibration of the system.2.The number of different bearing rolling elements has little effect on the vibration of the spindle system,and the influence on the axial vibration is much larger than the radial direction.During the starting time of 0?0.5s,the more the number of rolling elements,the smaller the system vibration;during the working time of 0.51s?1.0s,the change of the number of rolling elements has little effect on the vibration of the system,which is almost no.