Study on the Dynamic Characteristics of Three-Point Contact Ball Bearings Under Variable Operating Conditions

The three-point contact ball bearing, known for its high load capacity and compact structure, is widely used in high-end equipment such as aircraft engine spindles and precision machine tools. However, the dynamic response of its multiple contact points and the coupling mechanism of kinematic parameters remain unclear, particularly under complex loading conditions, where uneven load distribution, stress concentration, and sliding behavior at each contact point can lead to premature failure. This paper focuses on the dynamic characteristics of the contact points in the three-point contact ball bearing. By establishing a dynamic model based on Hertz contact theory and raceway geometric constraints, combined with multi-body dynamics simulations and bench tests, the contact characteristics of the bearing's contact points under axial and combined axial-radial loads are systematically revealed. The study shows that when only a pure axial load and small radial load are applied, the three-point contact ball bearing remains in a two-point contact state. As the load increases, the bearing reaches a three-point contact state, and the increase in maximum contact pressure may lead to premature bearing failure. Additionally, threshold points exist under both pure axial load and combined axial-radial load conditions. These threshold points determine the transition between slip and the loading and unloading of the contact area.