OPTIMIZATION OF COMPOUND PLANETARY GEAR TRAIN BY IMPROVED MESH STIFFNESS APPROACH

摘要

An improved mesh stiffness approach is presented for optimization of vibration and noise performance of the planetary gear trains in a full power split hybrid transmission, in which mesh stiffness time-variability and biaxial gear stiffness couplings in gear pairs are taken into account. For improving accuracy of the mesh stiffness in double teeth-meshing region for spur gear pairs, a simplified solution to the loading gear deformations counting for time-varying mesh stiffness of the helical gear pairs is proposed, based on the integral potential energy method and FEM simulation. By the new biaxial coupling model, effects of gear body and tooth coupled stiffnesses on gear pair vibro-acoustic responses are also investigated and approved to be considerable. Numerical examples with optimal analyses of the specified planetary gear trains for the full hybrid transmission are provided. Numerical solutions of eigen frequencies and vibration modes for the gear pairs with a variety of time-varying mesh stiffnesses are constructed by the biaxial coupling model and Fourier Series. The dynamic parameters optimization of the compound planetary gear train is then conducted. The optimized planetary gear system is applied in the full hybrid transmission and bench tests for its vibro-acoustic performance are also undertaken. Computational predictions and experimental results are shown to be in fairly good agreement.