Influence of meshing stiffness on load distribution between planets of planetary gear drives

Planetary gear sets are suitable for high power density and gear ratio, but this means high torques and stress levels. Though the torque is transmitted between multiple planets, it is not evenly distributed among them due to manufacturing and assembly errors. The torque is greater than the average value in some planets, and smaller in the others, which will have to be considered for strength calculations. In addition, this uneven load distribution among planets can also be affected by the meshing stiffness, if the planets are not at the same relative meshing position at any moment. In this paper, the condition for uneven distribution of the load between planets due to the meshing stiffness is established, and the calculation method of the corresponding influence factor is proposed.