The Study About the Gear Mesh Nonlinearity and Dynamic Characteristics of Planetary Gearbox

The gear mesh nonlinear characteristic is an important factor in planetary gearbox nonlinear study. However the gear meshing stiffness in many research papers is often calculated with formulas from handbooks. This kind of method is not reliable and accurate enough in the planetary gear box nonlinear characteristic study especially in the high speed transmission. The vibration and noise is becoming worse and worse with the increase of speed and it is necessary to find a more reliable and accurate method in gear meshing stiffness calculation. A new gear meshing stiffness calculation method of planetary gearbox is presented in the paper and the new method and its Matlab codes are general to the planetary gear sets. With the new gear meshing stiffness of sun vs. pinion and ring vs. pinion, the planetary gear box nonlinear model was built. The whole planetary gear box was simulated in low and high speeds and some important characteristics are obtained and compared. Through these studies, the conclusion can be made that the nonlinear characteristics of planetary gear box can be modeled and simulated with these nonlinear gear meshing stiffness obtained from FEM model and its code, it is obvious that this new gear meshing stiffness calculation method and the nonlinear planetary gearbox models built with these stiffness are much more accurate and practical in solving large complex planetary gearbox nonlinear characteristics.