Approaches to improving comprehensive strength of planet bearings based on a rigid–flexible coupling dynamic model

As the trend toward high-speed and heavy-load operations has gained momentum, planetary gear sets have become prevalent in power transmission systems. However, under revolution–rotation coupled conditions, planetary bearings face a significantly higher risk of failure compared to traditional non-revolution conditions. This study delves into the comprehensive strength of planet bearings under the revolution–rotation coupled conditions. A rigid–flexible coupling dynamic model incorporating cage flexibility is established. Failure risks, including roller–race contact failure and cage fracture, are thoroughly investigated. The influences of bearing parameters on comprehensive strength are revealed. Moreover, an optimization strategy for the bridge root is proposed, with optimal variables identified via the particle swarm algorithm. Dynamic simulations and experiments validate that the maximum cage stress can be reduced by over 24% without affecting the roller–race contact strength. Overall, this study substantially enhances the comprehensive strength and reliability of planet bearings.