Numerical and experimental study of gear rattle based on a refined dynamic model

Abstract

A refined single pair gear dynamic model is established to accurately predict the gear rattle. The model considers various key parameters, such as backlash, time-varying mesh stiffness, nonlinear oil film force between teeth and drag torque. The time-varying mesh stiffness of helical gears is calculated by using the potential energy method. The nonlinear oil film force is introduced into the model by considering the entrainment and squeeze effects of the lubricating oil between the teeth. In addition, the friction resistance caused by the squeeze of lubricating oil between the teeth is considered in the proposed model. The rotation speed and angular acceleration of the loose gear were measured on the bench, and compared with the simulation results, which proved the accuracy of the model. The results of the parametric analysis show that excessive torque fluctuation and backlash may lead to severe impact of the gear pair. Increasing the drag torque has a positive effect on the control of the gear rattle. Larger viscosity will make faster attenuation of high frequency impact and reduce the impact strength.