A mesh stiffness evaluation model to reflect tooth pitting growth of a pair of external spur gears

Tooth pitting is a common failure mode of a gearbox. With the growth of tooth pitting, gear mesh stiffness shape changes and consequently the dynamic properties of the gear system change. An efficient and effective way to evaluate the time-varying mesh stiffness is essential for comprehensive understanding of dynamic properties and fault detection of a gear system. This study is devoted to modeling gear tooth pitting growth using circular pits and analytically evaluating the influence of tooth pitting on the mesh stiffness of a pair of external spur gears. Equations of the mesh stiffness are derived using the potential energy method. The relationship between pitting severity and mesh stiffness is established.