A function method for static load-sharing analysis of multiple-branch power-split gearing system

Abstract

A function method was proposed for the static load-sharing analysis of the power-split gearing system. Taking a two-stage three-branch star gearing system used in a certain type of aircraft engine as the object, based on the deformation compatibility condition that considers the torsional deformation of the dual star gear shaft, the function that describes the changing rule of the load-sharing coefficient was established, which could calculate the load-sharing coefficient without the truncation error. Through analysing the load-sharing susceptibility to gear eccentricity errors with the traditional graphic and function method, respectively, the correctness and advantages of the proposed method were verified. Finally, considering the randomness of eccentricity errors in gear manufacturing and installation, the load-sharing coefficient function matrix was established to analyse the load-sharing characteristics when the errors were generated randomly. The result shows that the function method can avoid possible truncation errors in the load-sharing coefficient calculation and make the static load-sharing analysis more efficient; the randomness of the error value has a greater influence on the load-sharing than the randomness of the error direction; the randomness of the error direction may affect the susceptibility of the load-sharing to installation errors, which should be considered in the analysis of load-sharing susceptibility to the error with a fixed direction.