ES380336A1 - Sliding clasp fastener stringers - Google Patents

Abstract

A method of making a sliding clasp fastener stringer comprises locating a series 22 of coupling elements by means of a tubular guide 24 adjacent a longitudinal edge of a carrier tape as it is warp knitted, and knitting in the tape at least one yarn 20e which passes at least partially around the series 22 and interlinks with the other tape yarns 20 to secure the coupling elements. A warp knitting machine for this purpose comprises five yarn guides 12 movable in a controlled manner by guide bars 13 reciprocably mounted in supports 14 secured to a bracket 15 which is keyed to a shaft 16 and oscillated about axis 17 by a crank 18. A row of latch needles 11 are slidably mounted in a trickplate 10 and the lower end of the tubular guide 24 through which the series of coupling elements are fed, e.g. by a ratchet-operated wheel, is located adjacent a longitudinal edge of the tape 21 being knitted and can be reciprocated between two needles 11 (Fig. 6) to assume the position shown in Fig. 4. The swinging movement of the guide 24 is achieved by means of yarn guide 12d. The fabric of the tape is knitted by yarns 20 and the yarn 20e is guided by the yarn guide 12e which is reciprocated through the row of needles together with the tubular guide 24 and laps the needles adjacent the tubular guide when in the position of Fig. 4. With the yarn guide 12e in its displaced lateral position (Fig. 6) the tubular guide 24 and yarn guide 12e are returned to the position of Fig. 1 which loops the yarn 20e about the guide 24 when the needles 11 are then moved downwardly and upwardly to knit one course during which the yarn 20e is drawn from the lower end of guide 24 to encompass the series of coupling elements between two interlocking heads. Typically the lapping of the yarn 20e may be arranged such that three courses of the tape are knitted to each pitch of the coupling elements with the yarn 20e lapping the tubular guide twice in every three courses so that two loops encompass each coupling element. In a second embodiment the tubular guide is retained in a fixed position and a yarn guide is reciprocated such that it loops the yarn around adjacent needles to secure the coupling elements.