GB385411A - Improved means for use in examining the contours of gear wheel teeth - Google Patents

Abstract

385,411. Gauging toothed gears. GEAR GRINDING CO., Ltd. and SNARRY, J. W., Anne Road, Handsworth, Birming- ham. Nov. 30, 1931, No. 33097. [Class 106 (ii).] The gear b is coaxially secured to a circular fixed body a while a member e rotatable about the axis of the fixed body carries slidably mounted on it a part g on which in turn is mounted a slide h adapted to move at rightangles to the slide g and carrying a feeler j adapted to engage the gear teeth. A flexible band k is secured at one end to the body and after being wrapped partly around it is secured to a rack-bar l which engages a pinion m which is constantly acted upon by a torque supplied by a weight or spring. The bar is carried on the end of the part e between rollers n, n and the strap k. The part e, an extension o of the slide h and the rack-bar l or the strap are connected together by a link p. The latter is pivoted at the point r to the part e and is connected to the extension o by passing between rollers t in a part s pivoted to the extension. The link p also passes between rollers in a part u pivoted to the rack-bar. In use the gear to be tested is mounted on the spindle d and the slide g moved to bring the part s to a suitable position on the link p. The distance of the parts u, s from the pivot r are then in the ratio of the diameter of the body a to the diameter of the pitch circle of the gear b. The feeler j is also brought into engagement with one side of the tooth to be tested. The member e and connected parts are rotated as one piece about the body a. The feeler will traverse the face of the tooth which if correct will not cause the other end of the feeler to give an indication on the scale or to actuate a dial gauge.