Abstract: The governing equations for elasto-dynamic analysis of three-ring reducers are derived with consideration of many factors including the elasticity of driving and supporting shaft, the elasticity of the planetary and output shaft bearings, the elasticity of meshing gears and errors of the eccentric cranks in indexing and eccentricity. Based on the governing equations, the dynamic meshing force of three-ring gears is studied and the super-harmonic resonance is revealed. The intention is to provide a guideline to systematically dynamic analysis of three-ring reducers and upgrade their vibration performance.

Key words: Elasto-dynamic analysis, Error, Three-ring reducer