An Adaptive Preload Device for High-Speed Motorized Spindles for Teaching and Scientific Research

This study focuses on an experimental device for the adaptive adjustment of the preload of high-speed motorized spindles. Firstly, based on Hirano’s criterion, the optimal preload for bearings at different rotational speeds was determined, and an adaptive preload adjustment mechanism was developed, with its accuracy experimentally validated. Secondly, the optimal lubrication conditions were obtained by a single-factor experiment. Then, the vibration characteristics under different preload conditions were explored, and the axial displacement variations were analyzed across a range of rotational speeds. Finally, the temperature rise in the bearings with the speed at the constant preload force and the optimal preload force were compared. The results demonstrated that the adaptive preload adjustment device outperformed the constant preload application. In teaching practice, this study enhanced students’ systematic understanding of the adaptive preload adjustment process in motorized spindles, promoted the integration of theoretical knowledge with practical application, and strengthened their learning interest. In addition, this device can provide experimental equipment for studying the performance of high-speed motorized spindles and bearings in scientific research.