Abstract
In recent years, the needs of machine maintenance have led to demands of remote diagnostic techniques for gear-teeth. Different maintenance methods have been developed to diagnose damage to the gear-tooth surface using different techniques involving, for example, acoustic emission, sound, tooth root strain and vibration. However, for early detection of gear-tooth abnormalities, such diagnostic methods are not optimum. If the damaged tooth can be detected, it is difficult to grasp the damaged area on the tooth surface in detail. To address this problem, we developed a method that uses a laser beam. This method is as follows: A tooth surface is irradiated by the zonal laser beam from an oblique direction, and then the irradiated laser beam line is shifted along the surface of the tooth according to gear rotation. If the damage on the irradiated tooth surface exists, the output voltage proportional to reflection increases. In gear fatigue testing, we measured the gear by using the above-mentioned method. Then we found that owing to the increase of number of cycles, the output voltage proportional to reflection changes. Because teeth surface property are transformed every second by gear engagement. Nevertheless, we have not elucidated how roughness of tooth plane, displacement of tooth flank form, et cetera affect the output voltage. It has to be clarified to improve accuracy and apply this method. Therefore, in process of growing pitting fatigue we got the output voltage, roughness of tooth plane and tooth form error and investigated relationships by experimentation. In conclusion, we have the relation of three factors.
