Patent GB-1464444-A (GB)
Title: Stringers for sliding clasp fasteners and methods for their manufacture
IPC: B29D5/00
Filed: 1974-01-28
Abstract: 1464444 Weaving zip fasteners OPTI PATENT-FORSCHUNGSUND FABRIKATIONS AG 28 Jan 1974 [27 Jan 1973 5 July 1973] 632821/74 Headings D1E and D1K [Also in Division E2]  A method of making a stringer for a sliding clasp fastener 10 comprising securing a series of monofilamentary interconnected coupling elements 14 to a stringer tape during weaving of the tape includes the steps of providing a ground weft tape 13 which is to extend over the entire width of the tape, feeding the series of coupling elements 14 to a shed of warp threads in a position so as to be located on one side of the tape and to extend across a first part 15 of the tape width with a second part 9 of the tape width remaining for attaching the stringer to an article, and moving the series of coupling elements 14 in the shed in the manner of a warp thread while securing the series of coupling elements to the tape, moving some of the warp threads 12 for the first tape part 15 into a middle sheet position R m , Fig. 6, and moving the remaining warp for the first tape part into a lower sheet position R t , moving some of the warp threads 11 for the second part 9 into an upper sheet position U h  and moving the remaining warp threads for the second tape part into a lower sheet position U t , and alternating the position of the respective warp threads for both tape parts while the series of coupling elements 14 are moved alternately between upper and middle sheet position W h  and W t  respectively. The method also includes the essential steps of inserting loops of the ground weft thread between the lower and mid sheet positions and below the series of coupling elements 14 while inserting loops of the securing weft thread 16 between the upper sheet position W h  and the middle sheet position W t  of the series of coupling elements 14 and above the middle sheet position R m  of the warp threads 12 of the first tape part 15, the loops of the weft threads extending together between the warp threads 11 of the second tape part and being knitted to form a selvedge at the tape edge A remote from the series of coupling elements 14 whereby loops 17 of the securing weft thread 16 pass above and below the series of coupling elements so as to pass around the monofilament and secure the series of coupling elements in position on the tape. As shown in Fig. 1, the ground weft thread 13 and the securing weft thread 16 are inserted simultaneously from a side B of the tape, the thread 16 engaging the monofilament 14 inside the selvedge edge B and being knitted with the ground weft thread 13 at the selvedge edge A. The latter may, alternatively, be knitted by passing a selvedge edge knitting needle through both loops of the weft and knitting a selvedge thread (19) through the loops. A stuffer warp 66 may be provided inside the helical element 14 which may be woven in the base fabric against a thick base warp 67, Figs. 3, 4. The part 15 of the tape, Fig. 4, includes six auxiliary warp threads 69 which pass under and over the loops of the weft threads 13 in a ratio of 3:1. Weft insertion needles 22, 23, Fig. 7, are inserted simultaneously around a path L by a cam-operated linkage 39-44.