GB603098A - Improvements in or relating to a method of making cutter bits for mining machine chains - Google Patents

Abstract

603,098. Making cutter bits for chains. NEWTON, E. P. (Frank Prox Co., Inc.). June 14, 1945, No. 15120. [Classes 83 (ii) and 83 (iv)] Die rolling; punches and dies.-A method of making cutter bits for mining machine chains comprises forming on each side of a metal strip or bar, a series of spaced identical projecting members arranged at an angle other than a right angle to the length of the bar and with the projections on one side opposite the spaces of the other side, then punching out the members projecting on one side and thereafter similarly punching out the members on the other side. A bar 50, Fig. 7, is passed between die rolls 52, 53 formed with recesses 56 and 57 respectively so as to form members 37A on one side of the strip, alternating with members 37B on the other side. The formed strip is then fed to a punch comprising a base member 62, Fig. 8, having bars 63 defining ports 64 into which the projections may snugly fit and a punching die 65 having fingers 66 to co-operate with the ports 64, which are arranged at an angle to correspond with the angular set of the projections 37A, 37B. The projections on one side are first punched out and the strip inverted to remove the remaining projections on the opposite side. Cutter bits thus formed may need grinding on their edges and when finished have the shape of a segment of a double convex disc, with a flat face 39, Fig. 3, and two identical convex surfaces 40, 41 meeting in a sharp curved edge 42.