METHOD AND APPARATUS FOR PRODUCING A KNITTED FABRIC WITH PROJECTING BARBS

• US 3,845,641 A
• Filed: 07/01/1971
• Issued: 11/05/1974
• Est. Priority Date: 08/26/1968
• Status: Expired due to Term

• Current Assignee: Norbert Waller
• Original Assignee: Norbert Waller
• Inventors: Waller, Norbert
• Primary Examiner(s): Feldbaum, Ronald
• Application Number:
  US05/159,036
• Time in Patent Office: 1,223 Days
• Field of Search: 66/86,192,193,84,17,19 28/72HP 26/9
• US Class Current: 66/192
• CPC Class Codes: A44B 18/0038 Male or hook elements A44B18/003 takes precedence
• CPC Class Codes: D04B 1/02 Pile fabrics or articles having similar surface features
• CPC Class Codes: D04B 21/02 Pile fabrics or articles having similar surface features
• CPC Class Codes: D04B 23/08 with provision for incorporating pile threads
• CPC Class Codes: D04B 27/04 Sinkers
• CPC Class Codes: D04B 35/00 Details of, or auxiliary devices incorporated in, knitting machines, not otherwise provided for
• CPC Class Codes: D10B 2403/0113 One surface including hollow piping or integrated straps, e.g. for inserts or mountings
• CPC Class Codes: D10B 2403/023 Fabric with at least two, predominantly unlinked, knitted or woven plies interlaced with each other at spaced locations or linked to a common internal co-extensive yarn system
• CPC Class Codes: D10B 2501/0632 of the touch-and-close type

Abstract

A knitted fabric consisting of a base fabric into which while being knitted a supplementary monofilament thread of a thermoplastic material is knitted so as to form loops which are drawn out to a considerable length and are then set by a heat treatment and erected to an upright position relative to the base fabric either by stretching the latter or by means of special hook-shaped tools around which these loops are layed, whereupon these set and erected loops are fixed by a sizing material and are then cut open to form barbs with narrow heads which, when the entire fabric is pressed together with another pile fabric, become hooked together with this other fabric.

Claims

1. A method of producing a knitted one face fabric having courses and wales and on the back face of said fabric upstanding fastener elements being formed by projecting end parts of a multiplicity of cut monofilament threads of a thermoplastic material comprising the steps of knitting a base fabric, knitting at least one monofilament thread of a thermoplastic material into said base fabric so as to form loops on the back side of said base fabric and in said base fabric at least one stitch between each two loops, each of said loops having a pair of foot portions and a head portion, said pairs of foot portions entering into said base fabric in the same course and in two adjacent wales, stretching, heatsetting, and erecting said loops to an erected position so as to form long drawn loops, then dressing said knitted fabric with a sizing material to fix said long drawn loops in said erected position, and then severing at least a part of said long drawn loops to form said fastener elements.

2. The method as defined in claim 1, comprising the steps of placing said loops of said monofilament threads on the backside of said base fabric around loop holding means for stretching said loops in said erected position, heating said stretched loops and holding them in said stretched condition while a plurality of courses are knitted so that sufficient length of time is attained for heatsetting said stretched loops so as to form said long drawn loops, fixing said long drawn loops in said erected position and severing at least a part of them to form said fastener elements.

3. The method as defined in claim 2, comprising the steps of knitting said base fabric from at least two warp thread systems one of which knits in a pillar stitch arrangement and the other of which connects different wales to each other, knitting said monofilament threads in said base fabric by forMing a combination of a pillar stitch and weft insertion having weft parts crossing from one wale of said fabric to another, and wale parts extending in each of said wales between said weft parts, connecting the ends of said weft parts to said base fabric only by thread parts of said pillar stitch arrangement of said base fabric which thread parts extend from one course to the next course and connecting each of said wale parts by at least one stitch to said base fabric, winding at least a part of said weft parts of said monofilament threads around said loop holding means for stretching, heatsetting and fixing said long drawn loops in said erected position and severing at least a part of them to enable them to hook into an other fabric.

4. The method as defined in claim 2, in which said loop holding means are hook shaped and are arranged in endless rows, comprising the steps of moving said loop holding means along predetermined paths together with said long drawn loops during the formation of several courses and holding said loops in this way in an erected stretched condition said sufficient lengths of time for heatsetting them, and fixing them in said erected position.

5. The method as defined in claim 3, comprising the steps of holding said loop holding means within the spaces between adjacent needles by means of said loops disposed in a row parallel to the row of needles and aligning each of them in a vertical direction perpendicular to the row of needles, so that a plurality of said loops are sliding successively downwardly along each of said loop holding means and are held said sufficient length of time required for heatsetting them, and fixing them in said erected position.

6. A method of producing a knitted fabric having courses and wales and on one face of said fabric upstanding fastener elements being formed by projecting end parts of a multiplicity of cut monofilament threads of a thermoplastic material, comprising the steps of knitting first on a knitting machine having a first and a second needle system a two-face fabric having wales of stitches on each face by forming stitches on one face by knitting a one face base fabric on said first needle system and by forming stitches on the other face by knitting on said second needle system, at least a part of said stitches of said other face being formed by knitting of said monofilament threads in such a way into said base fabric that said stitches of said monofilament threads extend as elongated stitches over at least one course of said base fabric, each of said elongate stitches having a pair of foot parts and a head part, said foot parts being knitted into said base fabric and each of said head parts being connected with said base fabric by the foot parts of a stitch following in the same wale, stretching said two face fabric in the longitudinal direction of said wales of said two-face fabric so that said elongated stitches are drawn to a long drawn condition, heat setting said elongated stitches in said long drawn condition, releasing said head parts of said elongated stitches from said base fabric to form said long drawn loops by said elongated stitches, stretching said base fabric in the direction of said wales of said base fabric to erect said long drawn loops into erected position, dressing said base fabric with a sizing material to fix said long drawn loops in said erected positions, and severing at least a part of said long drawn loops to form said fastener elements.

7. The method as defined in claim 6, in which by knitting of said two-face fabric at least one subsequently removable thread is knitted into said two face fabric so as to form stitches on said other side of said two-face fabric to connect each of said head parts of said elongated stitches to said base fabric, and after stretching and heat setting said elongated stitches removing said removable thread so as to release said head parts of said elongated stitches from said base fabric to form said long drawn loops.

8. The method aS defined in claim 7, in which said two-face fabric is knitted on a circular knitting machine having as said first and second needle systems dial and cylinder needles, respectively, knitting said base fabric by one of said needle systems and said other side of said two-face fabric by the other of said needle systems, connecting said other side of said two-face fabric to said base fabric by said one needle system, and knitting said removable thread for connecting said heads of said elongated stitches to said base fabric at least by said other needle system.

9. The method as defined in claim 8, in which said removable thread is knitted by said cylinder and dial needles.

10. The method as defined in claim 7, in which said two-face fabric is knitted on a warp knitting machine having a first and a second needle bar, knitting said base fabric by said first needle bar and knitting alternatively a course of said elongated stitches and a course of said removable thread by said second needle bar and while knitting said elongated stitches periodically omitting the formation of other stitches of said second needle bar while the stitches of said base fabric are further knitted on said first needle bar.

11. The method as defined in claim 6, in which said other side of said two-face fabric is knitted so that said head parts of said elongated stitches are connected to said base fabric by said foot parts of said elongated stitches of the adjacent course so that all wales of said other face of said two-face fabric are formed only by said elongated stitches, and in which said base fabric is knitted so as to make it extensible, stretching said two-face fabric in said lonitudinal direction of said wales so that said elongated stitches are drawn to a long drawn condition, and eliminating a course of said elongated stitches near the end of said two-face fabric, and than stretching said two-face fabric to such an extent that the head parts of said elongated stitches will be released and erected by untying the connection between all of said elongated stitches within each wale in the same manner as the formation of runs to form said long drawn loops in said erected position.

12. The method as defined in claim 11, in which said base fabric is made extensible by knitting it longer than said other face of said two-face fabric.

13. The method as defined in claim 11, in which said base fabric is made extensible by using eleastic threads for those threads of said base fabric which do not connect said elongated stitches to said base fabric.