Abstract: A toothing testing apparatus includes at least one pair of measuring disks or balls of a certain diameter which are introducible into respective substantially diametrically opposed tooth spaces of a testpiece, and measuring probes each including a base part and a measuring part elastically secured to the base part and rockable relative thereto, for measuring the distance between the measuring disks or balls of said at least one pair, the measuring part having one of the measuring disks or balls attached thereto and the base part being housed in or against a stationary part of the testing apparatus. The measuring disks or balls are symmetrically positioned and automatically centered in the tooth spaces to be measured, and the depth of penetration of the measuring disks or balls into the tooth spaces is measured by the testing apparatus.

Abstract: Method for recording loaded running tooth contact patterns on navy or marine large reduction gears comprising the steps of providing a pair of meshing gears having transversely spaced teeth with surfaces subject to wear, coating the surfaces of as least one gear with a substance providing visual indication of tooth wear, running the gears under load, providing a platform adapted to move along the teeth and adapted to support and guide a video imaging probe, moving the platform along selected teeth while directing the probe at the contact surface of a transversely spaced "observed" tooth, and recording a video image of the observed tooth surface. The method further includes synchronizing the video image with the video image of an identification marker temporarily disposed adjacent to the observed tooth and synchronizing the video image with an audio record describing the tooth contact location and pattern.

Abstract: A gauge for checking the quality (accuracy; tolerance: trueness) of gear teeth is provided with a set of gauging teeth which, when the gauge is used, mesh with the teeth to be checked. This effects automatic alignment of the actual contact pins relative to the teeth to be checked.

Abstract: A gear checking machine for measuring the involute profile and the helical lead of a gear having a support table which is coupled to a base disc that is driven by a friction drive mechanism is disclosed. The friction drive is achieved by means of a small drive wheel which drives the large base disc which has its shaft coupled to the rotatable support table. An encoder having a small drive wheel which is frictionally driven by the large base disc is employed whereby the encoder supplies electrical output signals representative of the degree of rotation of the support table and the gear. Involute and lead checking probes are mounted so they may move in the horizontal and vertical directions, respectively, relative to the gear being checked.