GB376499A - Apparatus for gauging the shape and pitch of toothed gearing - Google Patents

Abstract

376,499. Gauging toothed gears. SOC. ANON. DES ENGRENAGES CITROEN, 31, Quai de Grenelle, Paris. July 9, 1931, No. 19817. Convention date, July 10, 1930. [Class 106 (ii).] The gear to be tested is rotatably mounted on a fixed axis and a finger is slidably mounted on the gear support to be displaced towards and contact with the gear which displacement is indicated, the finger being also displaceable tangentially to the gear to rotate it through a distance equal to the pitch of the teeth. The wheel R is mounted on a fixed axis and the gauging apparatus B carried on a slide 13 is provided with rack teeth T1, T2 constituting feeling fingers. Each of these fingers has two movements radially and tangentially of the wheel. The movement in the direction F1 corresponds to pitch and is obtained by means of slides 3, 4 moved by screws. Movements in the direction F2 are obtained by slides 5, 6 also moved by screws 12. An edge 14 of the slide 13 contacts with the external surface of the gear wheel for correctly positioning the gauge. In use, one finger T1 located at the starting point of the movement in the direction F1 is moved to penetrate into the teeth until it touches the profile of the gear. The dial indicator C is then set to zero. The indicator may be engaged by either of two levers 15, 16 on the ends of the fingers. The finger is then moved in the direction F1 through a distance which corresponds to the pitch and which is determined by a fixed stop. The gear wheel has thus been turned through exactly the pitch. The second finger T2 is now moved into contact with a tooth and the dial gauge should still read zero. One finger may be used merely for turning the gear wheel, the other, which is fixed in the direction F1 being used to penetrate into the teeth.