Dynamic Analysis of Helical Gears With Sliding Friction and Gear Errors

In helical gears, the meshing stiffness fluctuation caused by the time-varying contact lines and gear errors is a main factor affecting the dynamic characteristics of the helical gears. This paper proposes a new calculation model that can simplify the calculation of the length of time-varying contact lines, friction force, and friction torque. Moreover, this model is not subjected to any parameter of the gear. Instead of linear equivalent displacement, the normal force acted on the teeth is calculated by the time-varying deformation of the meshing spring, which is affected by the vibration displacement, installation error, tooth frequency error, and eccentric error of the gear. We establish the dynamic model of a helical gear system by considering the meshing friction, gear errors, and initial phases of errors. According to the model, the vibration characteristics are calculated and the influence laws of gear errors and supporting stiffness are obtained. Because we take into account the deformation of meshing spring, the dynamic responses of the helical gear system are more abundant than that in the previous studies. The proposed method in this paper can simplify the calculation of the time-varying meshing line, meshing friction, and torque of helical gears, and it may contribute in reducing the vibration and transmission noise of the helical gear system.