Cage parameters on friction within cage-pockets contacts and lubrication behaviors in ball-raceway contacts

Abstract

The dynamic motion of the cage and rolling elements in rolling bearings significantly influences lubricant redistribution and film formation. To investigate these complex interactions, a novel imental apparatus was developed by integrating a cage measurement unit into a ball-on-disc optical elastohydrodynamic lubrication (EHL) test rig. The influence of cage pocket positions, cage dimensions, grooved surface textures, and grease properties on film thickness and friction forces at the ball-raceway and ball-cage interfaces were studied. Results showed that the cage plays a crucial role in enhancing ball-raceway lubrication by redistributing lubricant across ball surfaces, with its effectiveness governed by positional clearances, grease type, and cage design. The lubrication state of the ball-raceway interface was found to be closely linked to the cage-ball interaction forces, requiring a delicate balance for optimal performance. Analyzing and optimizing the friction behavior between the cage and rolling elements, along with cage structure optimization, can guide the design of novel cage structures for improved bearing lubrication characteristics. These findings provide valuable insights into the complex lubrication mechanisms induced by the dynamic motion of the cage and rolling elements.