Improved kineto-static model of high-speed ball bearings under constant axisymmetrical load

This paper presents analytical and experimental results pertaining to the rotational speed dependence of the stiffness of ball bearings. The goal of this investigation is to develop a simple and easy to use model, yet capable of faithfully predicting the actual behaviour of the ball bearing. Therefore the complexity of the phenomena present in bearings is not fully modelled and only dominant phenomena necessary to estimate stiffness and contact loads are considered. The results have been validated by experimental measurements with different bearings under various rotational speed and preload conditions. Comparison of the predictions of the improved model with results obtained with other published models show significant differences even for the estimate of the static stiffness. These differences arise because other models do not properly account for kinematic changes when calculating the bearing stiffness.