GB704258A - Washer strip and method and apparatus for producing same - Google Patents

Abstract

704,258. Making washers. ILLINOIS TOOL WORKS. March 28, 1951, No. 7224/51. Classes 83 (2) and 83 (4). [Also in Groups XXV] Punching; twisting; embossing.-Toothed lock washers are made in strip form the washers being in a single row connected to plain marginal bands by tabs that permit easy separation. A single band may be used but preferably there is a band on each side. Such a washer strip may be wound into a coil, after tempering, for use in a subsequent machine such as a screw and washer assembly machine. To produce the strip of washers 26, Fig. 6, having inturned teeth 24, a strip 2, Fig. 1, is fed to a die set in which a punch and die 6 remove the interior of the washer, opposed dies 12, 34 impart the twist to the teeth, a combined punch and hold-down 8 blank out the space between adjacent washers leaving connecting tabs 64 with marginal bands 68, and a punch 10 with an annular edge 98 and pilot 94 forms indentations 100 to facilitate separation of the washers. The sides of the punch 8 have grooves in which cylindrical holddowns 74 slide, being retained in holes in the cylindrical head 36 of the punch 8 and maintained initially by springs 84 in advance of the cutting punch. The hold-downs are fitted with pilots 88. The indenting punch also yields, sliding in its holder as opposed by a backing spring 108. Additional locating pilots 14, 16, 18 are provided. The die set to produce strips of washers with internal teeth 238 indented between the teeth and the tabs 256, Fig. 13, is also illustrated and described. At the first step the central hole in the washer is punched. The punch corresponding to the punch 8 is grooved to form the free teeth on the washer. The twisting-dies follow this punch instead of being located in advance thereof, and the indenting punch is as before. Specifications 648,267 and 649,529 are referred to.