Influence of Planet Pin Stiffness on Load Sharing in Planetary Gear Drives

Others have done significant work on the subject of load sharing among the planets of planetary gear drives; a brief review of that work is presented. Little work has been done, however, to evaluate the utility of the Hicks type flexible planet pins in improvement of load sharing in a planetary gear stage. This work shows the potential value of the three variations of the Hicks type flexible planet pin used on cantilever carriers, and a new design of a low spring constant planet pin that can be used on straddle type carriers. This is done by the calculation of the spring constants of gear meshes, bearings, and various designs of planet pins using the finite element method for a specific design of a planetary gear stage with spur gears and eight planets. The result showed significant differences. Low spring constant flexible pins are shown to have significantly superior load sharing characteristics.