Development of a damage diagnosis for a gear using a laser beam (a proposal for a method of creating benchmark data to be used in diagnosis)

We developed a new diagnostic method by using a laser beam. 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 height of the tooth according to gear rotation. The variation of the voltage proportional to laser reflection between initial and present conditions are compared, and the condition of the tooth surface can be diagnosed for things such as initial or abnormal abrasion, pitting, etc. Furthermore, we developed a method of automatic and remote damage diagnosis on a gear tooth surface according to various gear specifications by using the angle-distance relation map which made from pre-measured data of same material and heat treatment, and taking into account the influence of adjacent teeth. The measured data agreed well with the predicted data made with this method, therefore we can diagnosis the condition of various products automatically.