Characterization of the skidding dynamics of rolling bearings considering cage flexibility

Cage is the most vulnerable component in the rolling bearing structure. Its flexibility directly affects the deformation of the cage, which changes the contact state between the cage and the rolling element, and thus affecting the skidding characteristics of the rolling bearings. The cage is discretized into mass blocks connected by springs and dampers to consider its circumferential flexibility, and a dynamic model of the shaft-bearing-housing system is proposed by considering contact force, damping force, friction force, oil film stiffness, viscous drag force, and elastic support of the shaft and housing. The variations of the contact force between the cage and rolling element and the internal force of the cage are analyzed. The effects of the cage's connect stiffness, rotational speed, and load on the skidding characteristics of the rolling bearings are investigated. The results show that the dynamic interaction between the cage and rolling element is influenced by cage flexibility. The dynamic model considering cage flexibility can more realistically reflect the skidding in rolling bearings. Increasing the connect stiffness results in higher internal forces in the cage and a lower skidding ratio.