Simplified damage diagnosis on a gear tooth surface using a laser beam (Application to a helical and/or profile shifted gear)

We have developed a method to diagnose damage using a laser beam. Our method can be explained as follows: First, a tooth surface is irradiated by a 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 revolution. The variations of the laser reflection between the initial and the present conditions are compared. And then it can estimate the condition on the tooth surface such as initial or abnormal abrasion, pitting, spalling, etc. To apply this method for a helical gear, the arm for setting the laser sensor was assumed as the special closed-loop serial-linkage, and the structure of the arm was proposed. By using these proposals, the data calculated from laser reflection and measured with caliper were compared. As a result, we could diagnose the helical and/or profile shifted gear as well as a spur gear, and the difference was up to 8 [%].