Dynamics meshing efficiency of herringbone gears under mixed elastohydrodynamic lubrication condition

In order to accurately establish the dynamic model of helical gears, and to know more about vibration characteristics of the helical gear system, a meshing stiffness calculation method was put forward based on tooth contact load analysis and in consideration of the torsional deformation of shaft. The dynamic models of helical gears established by the decomposition of meshing stiffness in major domestic literatures were analyzed and their violation of theoretical mechanics was pointed out. Based on the decomposition of force and vibration displacement, a vibration model of helical gears was established considering the meshing stiffness excitation and corner meshing impact excitation. Taking a helical gear transmission system as an example, the results consistently indicate that the method of tooth contact load analysis can easily and accurately calculate the teeth meshing stiffness. The results based on the decomposition of force and vibration displacement are in good agreement with the theoretical ones.