Time varying meshing stiffness of cracked gears in service

Gear transmission system, as a device for transmitting motion and power, has been widely used in various machines and mechanical equipment due to its advantages of constant power transmission, high efficiency transmission, large capacity bearing and long-time reliable operation. However, due to the complex structure of gear system itself, most of them work in closed environment, resulting in high failure rate.

Crack is one of the most typical fault forms of gear transmission system. There are many researches on gear crack at home and abroad, but they are lack of systematic development. Focusing on the problem of crack fault in gear system, this paper mainly discusses the crack propagation path and the solution method of time-varying meshing stiffness in crack fault, and looks forward to its further research direction, so as to provide help for fault diagnosis of gear system.

Gear crack affects the vibration, noise and service life of gear system. The study of gear crack is the basis of gear fault diagnosis and an important means of residual life prediction of gear system. Although scholars at home and abroad have made remarkable achievements in the study of gear system crack fault, there are still several aspects to be further studied, such as:

(1) The mapping relationship between gear crack and time-varying meshing stiffness is established.

(2) The influence of various cracks on the stiffness is different.