GB379930A - Improvements in or relating to chasers for cutting screw threads - Google Patents

Abstract

379,930. Chasers. MANNES. MANNRÍHREN-WERKE, 1B, Berger Ufer, Dusseldorf, Germany. Dec. 5, 1931, No. 33807. Convention date, Dec. 17, 1930. [Class 83 (iii).] Screw - cutting chasers having at least the cutting edges made of high - speed cutting materials, particularly those such as the tungsten - carbide cobalt group, are formed of a number of separate strip or disc cutters E secured together by screws, rivets, clamps, &c., each cutter constituting one tooth of the chaser. When the screw thread produced has flat apices and bases, additional cutters E1 may be secured between the cutters E, and the cutting edges may be arranged on a line perpendicular to the cutters, on a line a-a inclined at some other angle to the cutters, as shown in Fig. 7, or may be at different distances from a perpendicular or inclined line a-a, as shown in Fig. 8a, in order to vary the cutting effects of the respective teeth. The cutters may be made entirely of the cutting material or may have tips soldered or welded thereon as shown at p in Fig. 9. The chasers may be used in tangential die-heads or in a die-stock.