Analysis of Internal State Performances of the Electric Spindle Bearings Running at an Extreme Ultra-High-Speed

Aiming at the problem of analyzing for the dynamic performances of the spindle bearings running at an extreme ultra-high-speed in high-speed electric spindles, a model is built by taking the inertia effects and EHL at the extreme ultra-high-speed into account. Based on the system simulation about a bearing on the movements of every ball, the contact areas states and the lubrication states between balls and both ring raceways, the thermal state inside the bearing and so on, the internal state performances such as the movements and the inertia forces of all the balls, the contact forces and the lubrication films and the temperatures in the contact areas between balls and both ring raceways are analyzed in some different working conditions and configurations. The simulation results showed that the main factors affecting the state performances of a bearing running at an extreme ultra-high-speed are the inertia effects of the balls and the overheating in the contact areas between the balls and both ring raceways, which indicates that it can be improved by adopting the ball material with smaller mass density and the structure with a smaller ball diameter and more ball elements.