Patent ID: 8672797
Filing Date: 2014-03-18
Classification: F03D,F05B,F16H,Y02E

Abstract:
1. A planetary gear system, comprising: an input shaft; an output shaft; a split-compound planetary gearing system including a high-torque stage and a low-torque stage, said split-compound planetary gearing system configured to transfer torque from said input shaft to said output shaft through said high-torque stage and said low-torque stage; said high-torque stage being configured as a closed-carrier flex-pin planetary gear system incorporating two opposing planetary gear arrays disposed within a closed carrier having opposite end walls, each planetary gear array comprising a plurality of planetary gears supported by cantilevered flex-pins extending inward from an associated end wall of said closed carrier, each of said planetary gears engaged with a common ring gear coupled to said input shaft and to a common sun gear coupled to a ring gear of said low-torque stage, the flex-pins, in conjunction with the carrier walls from which they are cantilevered to support an associated planet gear, insuring sufficient flexibility to equalize the load among the planet gears in response to an applied load, so to provide an axial bending pattern that maintains an optimum gear mesh alignment between the planet gears, sun gear, and ring gear throughout a range of loading; said low-torque stage being configured as an open-carrier flex-pin planetary gear system; and, the planetary gear system maximizing a step-up ratio between the input shaft and output shaft within a limited radial space defined by the ring gear size of the planetary gear system.