GB841629A - End stop for sliding clasp fasteners, and a method and device for producing and mounting the same - Google Patents

Abstract

841,629. Making sliding-clasp fasteners. OPTI-WERK G.m.b.H. & CO. Jan. 17, 1957 [Jan. 17, 1956], No. 1783/57. Class 83 (2). [Also in Group XXV] A sliding clasp fastener is provided with an end stop which is tapered at one end 2, Fig. 1, and has two tips 3, 4 at its other end formed by cutting away a segment having the same shape as the tapered end; the end stop being bent around an initial clasp member of the fastener. A flat metal strip is fed to a cutting and bending punch 9, Fig. 9, which severs blanks therefrom, shaped as in Fig. 1, by consecutive cuts, and further lowering of the punch 9 bends each blank about the broken lines shown in Fig. 1 to U-shape; the central part 5 being supported in a slot 10 of a bending tongue 11. Beneath this tongue a clinch-plate 14 is disposed having a shallow groove containing the wire spiral 6 and the associated stringer tape 7 of a sliding clasp fastener. The side-faces 11a of the bending tongue extend upwardly to embrace a clinch punch 13 having a plane lower face 13a and side projections with sloping lower edges 11b which cam against similarly sloping upper edges of the faces 11a. After formation of the U-shape blank the clinch punch is lowered, thereby causing the bending tongue 11 to be cammed out of engagement with the blank, and presses the blank against the groove of the clinch-plate. 14, causing it to encircle and grip the end of the wire spiral ; the teeth 3, 4 passing through the tape 7 and embracing the end 2 of the blank. A stop 16 provided in the clinchplate groove correctly locates the end of the spiral relative to the blank. Before cutting and bending, the wire strip may be lacquered to match the colour of a plastic wire spiral; the lacquer being suitable to withstand the bending and rolling processes.