GB173609A - Improvements in or relating to tool grinding devices - Google Patents

Abstract

173,609. Gouldbourn, J., Ricks, F., and British United Shoe Machinery Co., Ltd. Oct. 4, 1920. Cutting-edges, shaping; gauges; work-holders.-In a machine for grinding the cutting-tools of tapernail tacking machines, devices are provided on the cutter-support for locating, in succession, the two different cutters, and a gauge is provided for testing the accuracy of grinding. The cutters 12 to be ground are of the form shown and are of different thicknesses, the thicker cutter having its cutting- edge 40 radial to the centre of the concave side of the cutter, and the thinner cutter having its cutting- edge slightly to one side of a radial line. The machine comprises a grinding-wheel 1 of the form shown in Fig. 3, which grinds with its side face, and a pivoted cutter-support 10 adapted to be oscillated by hand to move the cutter-edge across the grinding-wheel. The support 10 is inclined towards the wheel to give baching-off to the cutter, and is formed at the upper end of an arm 4, which is rotatably mounted on a shaft 3 fixed in the machine frame. The arm has lugs 5 thereon engaging a pin 6 for limiting its oscillatory movement, and is movable along the shaft 3, to adjust the position of the cutter, by a screwed rod 7 operated by a hand-wheel 8. The support 10 has on its upper face a pin 13 for positioning the front end of both cutters, and a pin 17 with a cylindrical head 16 for positioning the rear end of the cutters, the thin cutter just passing under the head and contacting with the pin 17, and the thick cutter engaging the head. The cutters are clamped in position by a block 18 moved in a slot in the support by an eccentric operated by a pivoted handle 20. The progress of the grinding is tested by a gauge-face 24 on an arm 25 secured to a shaft 26 mounted in the arm 4. The gauge is moved into and out of position, through an arm 28 pivoted to a rod 31, by the oscillatory movement of the arm 4, movement of the arm 4 into the grinding position moving the gauge to the inoperative position, Fig. 3. When the cutting-edge is to be tested, the arm 4 is swung clear of the grinding position, and the rod 31 moves until stopped by a spring 33 and a collar 34 thereon; the gauge then moves into the operative position. The edge of the cutter is correctly ground when the gauge face and the end of a pin 36 on the arm 25 engage simultaneously along the edge and with a stop 37 respectively. In a modification, the gauge may be moved by a fixed cam which engages the arm 28, a coiled spring on the shaft 26 pressing the arm 25 towards the cutter. Specification 1493/93 is referred to.