2014 年 8 巻 3 号 p. JAMDSM0034
Recently, infrared imaging technologies have been developing in various industrial fields rapidly. We therefore focus on the infrared ray imagery as a novel method to estimate the gear tooth meshing. In the present report, a high response infrared thermography, which could take a middle infrared ray image of around 4 μm wavelength, was used to investigate the temperature hysteresis on the tooth contact surface of hypoid gear under running conditions. We installed the high reflective mirror of infrared ray at the opposite side of the gear tooth meshing point to obtain the tooth surface images around the entire gear, and estimated the variation o tooth surface temperature at the duration from a tooth meshing to the next tooth meshing. Moreover, using a thermal network model, the modeling of the temperature variation of the gear tooth surface regarding the time is conducted as to predict the temperature after a certain number of rotations. The network model presented in this report is derived from the ones such as Forster network or Cauer network which are based on the concept of thermal capacitance and thermal resistance. This network is investigated to match the actual results on the temperature evolution. Finally, it is clear that the temperature on the tooth surface during a gear rotation can b modeled by first order time delay and the maximum temperature is affected by contact pressure, relative sliding speed between tooth surfaces and average peripheral speed of tooth surface. This proposed method is found to be effective to evaluate the temperature hysteresis on the tooth contact surface of hypoid gear.
