Method and apparatus for recording loaded running tooth contact patterns on large reduction gears

An improved method for recording loaded running tooth contact patterns on mating gears comprising:

• providing a pair of meshing gears having transversely spaced teeth with contact surfaces subject to wear,
• coating said contact surfaces on at least one of said gears with a substance providing a visual indication of tooth wear,
• running said gears under load,
• providing a platform mounting a video imaging probe,
• adjusting said video imaging probe on said platform to direct the probe at the contact surface of a transversely spaced tooth to be observed,
• moving said platform along the length of selected teeth while directing the probe at said contact surface, the platform having at least two guide elements each supported between a pair of adjacent gear teeth in order to guide said probe along the length of said selected gear teeth, said at least two guide elements located to one side of the tooth to be observed, and
• recording a video image of said contact surface of said observed tooth.