180 / 2024-09-01 12:09:14

Vibration feature of spur gear transmission

Crack fault Slice method Mesh stiffness

Gear tooth root crack is a typical fault of gear transmissions and it threatens the operation safety

of gear systems. Therefore, precise detection of the tooth root crack is of a great significance for

the prevention of serious safety accidents. As one of the commonly used methods, vibration-based

detection has drawn great attentions. However, the mapping relationship between the vibrations

and the severity of tooth root crack has not been established well, especially for the crack with

non-uniform distribution due to the complexity of its dynamic modelling. To address this prob­

lem, an improved gear dynamics model considering non-uniform distribution of the gear tooth

root crack fault is established in this paper by using the ‘slice method’. Compared with the

traditional methods, the advantage of the proposed model is that it enables the accurate

modelling of the non-uniform dynamic mesh forces along tooth width that will further excite the

support bearings. Then, the dynamic simulation of the gear transmission with non-uniform tooth

root crack is performed. The results indicate that the improved model can reveal the vibration

characteristics of the gear transmission due to the extra roll and yaw motions caused by the non-

uniform tooth root crack. In addition, the correlation between the vibration and the crack size and

location is quantified. This study could provide theoretical reference for quantitative detection

and diagnosis of gear tooth root crack.