Dynamic modeling and study of slipping and friction characteristics of four-point contact ball bearings under the angular misalignment

Four-Point Contact Ball Bearing (FPCBB) is utilized in aero-engines, wind power and industrial gearboxes due to its ability to withstand axial forces in both directions, its high-speed performance, and its space-efficient design. It has been demonstrated that the structural characteristics of multi-point contact have some advantages, and at the same time increase the friction between the balls and the raceways. In this study, a dynamic model of the FPCBB is developed by considering six degrees of freedom for the ball and cage, and five degrees of freedom for the inner ring, incorporating nonlinear collision and frictional interactions among components. The model accounts for potential multi-point contact between the ball and raceway, as well as the angular misalignment of the inner ring. The maximum error between the experimental and simulated cage speed is only 4.98%, confirming the model’s accuracy. Based on this model, the vibration response of the bearing under angular misalignment, along with frictional characteristics are analyzed. Structural optimization is then performed based on these results. Additionally, the effects of angular misalignment and axial preload are evaluated. The findings indicate that the maximum PV value in the main load area under fixed-pressure preload is approximately 70% of that under locating preload. This study is aimed to provide a theoretical foundation for understanding the dynamic characteristics of these bearings under angular misalignment and for parameter selection in practical service applications.