Mesh stiffness calculation using an accumulated integral potential energy method and dynamic analysis of helical gears

As one of the most important dynamic excitation sources, the gear time-varying mesh stiffness is the key parameter of gear system dynamic model. So how to calculate the gear mesh stiffness accurately is of great importance. In this paper, an accumulated integral potential energy method is proposed to calculate the mesh stiffness of helical gears. Compared with the finite element model (FEM) and the ISO standard, the proposed analytical method is verified as its results agree well with the others'. Meanwhile the effects of different helical gears parameters (e.g., helix angle, normal module) on mesh stiffness are studied. The results show that the fluctuation degree of mesh stiffness becomes smaller as helix angle or face width increases, by contrast the influence of normal module on the mesh stiffness shows an opposite trend. Furthermore, the mesh stiffness reduction of helical gears due to the tooth crack is quantified. Finally, a dynamic model of helical gear transmission is established to study the vibration characteristics of helical gears. The results show that the mesh stiffness plays a vital role in controlling the vibration of helical gears and has a significant effect on the vibration characteristic of helical gears with tooth crack.