Elasto-dynamics of internal gear planetary transmissions

An internal gear planetary transmission is an innovative type of transmission with unique advantages over traditional gear transmissions. However severe vibration, premature fatigue of bearings, high level of noise and heat producing block its further application in industry. In this paper, an elasto-dynamic model is developed and computer simulation is carried out. This model considers the elasticity of bearings, shafts and gear meshes. The dynamic load of bearings and gears is calculated based on the simulation program and the results are analyzed. The result shows that the planetary bearings are in more severe load conditions compared with housing bearings. And parametric resonance will occur when input speed is close to 1/3, 1/6 and 1/9 of the mean primary frequency.