Computerized design, analysis and optimization of a novel planetary threaded roller bearing with combined tooth profiles

The planetary threaded roller bearings (PTRB) sustain higher axial loads than traditional thrust roller bearings but suffer from large contact stresses at the initial thread teeth. In this study, the PTRB is redesigned by incorporating combined tooth profiles and the convex-concave contact mode, effectively reducing contact stresses at the initial thread teeth. A load distribution model is developed to characterize contact stresses at the inner ring-roller and roller-outer ring interfaces. A multi-objective optimization model using the feasibility identification-based NSGA-II algorithm is established to improve static axial load rating and fatigue life. Since some Pareto-optimal solutions perform worse than the initial design, a high-quality solution region is defined, whose solutions consistently enhance the transmission performance and durability of the PTRB.