Investigation of meshing phenomenon of hypoid gears with different offsets via high response infrared video thermography

Hypoid gears are widely used in automobile differentials. Furthermore, it is well known that the efficiency of hypoid gears is lower than that of other gears due to offsets. However, only a few studies have focused on offsets. Thus, it is important to understand the meshing phenomenon of hypoid gears with different offsets. In a previous study, we attempted to develop a novel method to analyze tooth contact conditions as a non-contact analysis method based on monitoring the temperature distribution during meshing between the pinion and gear surface. We also developed a novel method to predict the tooth surface temperature in tooth meshing based on a thermal network model that represents the thermal conductivity of the object by a simple RC circuit. In this study, thermal images were taken by thermography, and the tooth root stress was measured for gear pairs with different offsets. The temperature increase under each offset condition was simulated using a thermal network model. The results demonstrated the versatility of the thermal network model. Monitoring the tooth surface temperature by thermography was useful for understanding phenomenon of gears with different offsets.