GB577218A - Improvements in or relating to a gear testing machine - Google Patents

Abstract

577,218. Gauging toothed gearing. KODAK, Ltd. Feb. 7, 1944, No. 2252. Convention date, March 4, 1943. [Class 106 (ii)] Apparatus for checking toothed gears comprises a base carrying a slideway in which a worm section rack is mounted and a work holder for rotatably supporting a gear-wheel to be tested with its teeth meshing with the rack, the work holder being mounted on an angularly movable post carried by a slide movably mounted on the base. The gear-wheel W to be tested is mounted on a spindle 33 carried by a plunger 40 mounted in a head 25 and counterweighted by a spring 63. The head is mounted on a post 19 on which it may be moved vertically by rack-and-pinion gearing 26, 27. The post 19 is rotatably mounted in a slide 18 on the base 10. A master bar T with worm section teeth as described in Specification 577,217 is mounted for longitudinal movement in a groove 2 in the base while mating with the gear-wheel. An indicator 52 with a plunger 51 contacting an anvil 49 carried by the plunger indicates imperfections in the teeth of the wheel when it is rotated by movement of the master bar. The axis of the spindle 33 is set for height by placing gauge blocks between it and a test pad on the master bar. Alternatively, setting is achieved by means of a micrometer spindle carried by the head 25. The head is set angularly according to the lead on the wheel teeth by using a micrometer to measure the distance in plan between the central lines of pins 71, 72. This distance is the chord subtending the setting angle in a circle of the known radius D. Flat faces are provided on the pins to enable gauge blocks to be used instead of a micrometer. A coverplate 80 threaded over the teeth of the master bar protects from dirt the groove in which the bar slides.