Patent GB-891412-A (GB)
Title: A method of and apparatus for manufacturing slide fastener elements
IPC: B29D5/06
Filed: 1959-07-23
Abstract: 891,412. Moulding helical sliding-clasp fasteners. YOSHIDA, T. July 23, 1959 [Oct. 8, 1958], No. 25395/59. Class 87(2). [Also in Groups IX and XXV] Fastener elements for slide fasteners are manufactured by continuously feeding a wire of thermoplastic synthetic resin along and winding it around a mandrel, to form the wire into a helical coil of uniform and predetermined pitch, heating the wire while it is being so wound and advanced along the mandrel, intermittently stopping the advancing motion of the helical coil so formed, and applying a punching action to successive portions of the coil when stopped to form on the individual coils of each of those portions engaging elements for a slide fastener. As described a supply reel 5, Figs. 1 and 2, for the wire 6 is rotatably mounted on a shaft 7 which is fixed to a gear disc 11 driven through a gear 14 by a suitable driving means (not shown), the shaft 7 having fixed to its upper end an arm 10 carrying a spiral coil forming die 3 to which the wire 6 is fed. The die 3, Fig. 3, is in halves interconnected by a bolt 60 and has a central hole 40 through which passes a mandrel 1 around which the wire 6 is wound, the hole 40 having formed therein a spiral groove 4 to which the wire 6 passes by means of a bore 41. The die 3 is provided with an annular groove 42 on to which is blown hot air supplied through a nozzle 15. The mandrel 1 extends between a holder 2 and a block 32 mounted on a framework A to which is secured a post 12 extending coaxially with the mandrel 1 but on the opposite side of the framework A, the post 12 having rotatably mounted thereon the disc 11. The tension of the wire 6 is kept uniform by means of a compression spring 9 acting between the upper flange of the reel 5 and the arm 10 and by means of a slide 34 slidably mounted on a post 33 which is carried on an arm 8 fixed to the shaft 7, the slide 34 being maintained in a neutral position by opposed compression springs 28, 35 and being provided with a hook 37 slidably engaging the wire 6 which subsequently passes over a guide roller 38 to the bore 41. The apparatus is set by manually separating the halves of the die 3, inserting the wire 6 through the bore 41 and winding the wire round and up the mandrel 1 until it is engaged by advancing means 24, the halves of the die 3 being then engaged together again. Rotation of the die 3 forms the wire 6 into a continuous spiral coil S in the spiral groove 4, the coil being continuously moved up the mandrel 1; the coil S passes successively through a heater 16 to remove any stress in the coil, past a cooling nozzle 17 for setting the coil, through a punching head provided with reciprocating dies 18, 19 for forming portions on the coil for engaging similar portions on another such coil when the coils form part of a slide fastener, past a cooling nozzle 27 for again setting the coil, through the advancing means 24 and finally out through a guide pipe 26. The advancing means 24 is in the form of a spur gear, the teeth of which engage the turns of the coil S and the gear is so mechanically connected to the dies 18, 19 that the gear rotates only when the dies 18, 19 are open but does not rotate when the dies close, the gear and the dies being indirectly driven by the gear disc 11. The die 18 is heated and the dies are slidably mounted on a base plate 43, Fig. 4, fixed relatively to the framework A and are moved to their closed position against the action of springs 52, 51 by movement of a reciprocating rod 22 and a lever 31, the latter being pivotally connected to the rod 22 and pivotally supported at 45 on the base plate 43. Movement of the rod 22 and so the lever 31 is effected by a rotating cam 21 which engages a roller 23 rotatably mounted on the rod 22.