METHOD FOR ANCHORING LENGTHS OF ADDITIVE THREAD/FIBER THREAD ON THE BACK SIDE OF A KNITTED FABRIC

Abstract: A method for anchoring lengths of additive thread/fiber thread (2) in a knitted fabric in an ordinary knitting process, for example, on a circular knitting machine, where a row of vertical needles (10) is continually and successively moved from a lower position up to an upper position and down to a lower position again during formation of knitted stitches (A) interlocked with each other. The fiber thread lengths (2') that are inserted during this ordinary knitting process are anchored in the knitted fabric by the thread ends (2a) of the fiber thread length being deflected backward relative to the knitting direction and brought down between two new stitches (A'', A'') formed by the repeated operation of the needles (10), in two adjacent stitch rows, and being anchored between said stitch rows by the closing of the insertion opening (B) therebetween by the new stitches (A) formed thereafter through the next repeated operation of the needles (10) and by the tightening of the formed stitches. In this manner the ends (2a) of the fiber thread length (2') are securely locked in and project out from the knitted fabric.

Description: -METHOD FOR ANCHORING LENGTHS OF ADDITIVE THREAD/FIBER THREAD ON THE BACK SIDE OF A KNITTED FABRIC. The present invention relates to a method for anchoring lengths of additive thread/fiber thread in a knitted fabric in an ordinary knitting process, for example, on a circular knitting machine, where a row of vertical needles is continually and successively moved from a lower position up to an upper position and down to a lower position again during formation of knitted stiches interlocked with each other, as is disclosed in the preamble to the following independent method claim 1. Knitting machines, particularly circular knitting machines or flat knitting machines of the above indicated type, are commonly known and used for knitting fabric having inlaid lengths of additive thread/fiber thread for the provision of a shaggy or napped surface on the knitted fabric produced. By means of the known knitting machines, the inlaid fiber thread lengths are secured to the stitch in which they are inserted only by the formation within said stitch of a new stitch, and the subsequent tightening of the stitches. In other words, when one end of the length of fiber thread is pulled, the thread slides out of its attachment in the knitted fabric. The purpose of the present invention is to provide a better means of anchoring the lengths of fiber thread on the back side of the knitted fabric so that said thread cannot without undue effort be pulled out by drawing on one of its free thread ends projecting up through the preceding stitch through which the last stitched formed with the length of fiber thread was drawn down. This is achieved according to the invention with the aid of the features disclosed in the characterizing part of the following method claim 1 and in the subsequent dependent method claims. The method according to the invention will be described in more detail below, with reference to the drawing, which schematically shows a knitting needle in various positions and in engagement with a stitch thread and a fiber thread during the formation of stitches in a knitted fabric. Figure 1 shows a needle with closed needle head or hook in lower position with a newly formed stitch with an inlaid length of fiber thread, Figures 2, 3A and 3 show, respectively, the needle with open head during Its passage through said stitch to an upper position for catching a length of fiber thread, and sub¬ sequent downward movement for picking up a stitch thread, Figure 3B shows the needle head in engagement with the additive thread, which is simultaneously cut into the desired thread length, Figure 4 shows the needle with the stitch thread caught therein, for further movement downward through the last formed stitch and to the lower position, Figure 5 shows said lower position, where a first length of fiber thread is anchored by injection of the free ends of the fiber thread in between two newly formed adjacent stitches in two adjacent stitche rows, and Figure 6 shows Figure 5 in larger scale, showing the two last formed, adjacent stitches and the space between them, into which space the ends of the length of fiber thread is injected. The method acording to the invention is illustrated in the drawings in the following figures. Figure 1 thus shows a needle 10 having a closed needle head 10a in lower position, and a newly formed stitch A' with an inlaid fiber thread length 2'. Figure 2 shows needle 10 with an open head 10a during passage upwards through said stitch A' to the upper position for catching fiber thread length 2', as shown in Figure 3A, and subsequent movement downwards as shown in Figure 3 for picking up stitch thread 1 from thread guide 5, as shown in Figure 4, from which position needle 10 with the fiber thread length 2'' and stitch thread 1 are brought further down through the last formed stitch A' with the inlaid fiber thread length 2 ' as shown in Figure 5. It is also shown in Figure 5 how a first fiber thread length 2' is anchored in the knitted fabric by injection of the free ends of the fiber thread length 2'' in between two newly formed adjacent stitches A'' in two adjacent stitch rows. The air stream for injection of said thread ends 2a is designated C and is provided by means of an air tube 6 positioned in a suitable direction for deflecting and blow- injecting said thread ends 2a. The novelty of the method according to the invention is, thus, that the free ends 2a of the fiber thread length 2' are deflected backward relative to the knitting direction and are brought down between two new stitches A'', A'' formed by the repeated operation of needles 10, in two adjacent stitch rows. Fiber thread length 2' is then anchored between the stitch rows by the closing of insertion opening B therebe¬ tween by the new stitches A (not shown in the drawing) formed thereafter through the next repeated operation of the needles 10 and by the tightening of the formed stitches A. In this manner the ends 2a of fiber thread length 2' are securely locked and project out from the back side of the resulting knitted fabric. The deflection of the free fiber thread ends 2a backwards and in between the last formed stitches A' ' , A'' is, of course, not limited to the aforestated use of a periodic air jet C. Such a periodic deflection force on the fiber thread ends 2a may be provided, for example, by means of a periodically generated negative pressure, whereby the fiber thread ends 2a are sucked in between said last formed stitches A'', A''. It is further conceivable that the deflection force could be provided by means of a periodically generated magnetic field or a periodically produced electrical field of force, including static electricity. Also, the deflection orce could conceivably be provided by means of mechanical influence. A combination of the aforementioned possibilities for providing deflection force could also be employed.

Claims: P a t e n t C l a i m s 1. A method for anchoring lengths of additive thread/fiber thread in a knitted fabric in an ordinary knitting process on, for example, a circular knitting machine, where a row of vertical needles (10) is continually and successively moved from a lower position up to an upper position and down to a lower position again during formation of knitted stitches (A) interlocked with each other, from stitch threads (1) that are supplied via thread guides (5), for production of knitted fabric, and where during formation of each stitch (A), the needle (10) in upper position is supplied with a fiber thread length (2') from a fiber thread (2), before the needle on downward movement thereof grips the stitch thread (1) and draws this together with the fiber thread length (2') down through a preceding stitch (A) to form a new stitch (A') with inlaid fiber thread length (2') having free thread ends (2a) that project up through the preceding stitch (A), whereafter the needle (10) from lower position is again moved up through the new stitch (A') during simultaneous release of the needle's (10) head (10a) from said stitch and said fiber thread length (2'), to the upper position for supply of a new fiber thread length ( 2 " ) from the fiber thread (2'), whereafter the operation is repeated, c h a r a c t e r i z e d i n that the free thread ends (2a) of the fiber thread length (2') are deflected backward relative to the knitting direction and are brought down between two new stitches (A'', A'') formed by the repeated operation of the needles (10), in two adjacent stitch rows, and are anchored between said stitch rows by the closing of the insertion opening (B) therebetween by the new stitches A (not shown) formed thereafter through the next repeated operation of the needles (10) and by the tightening of the formed stitches, whereby the ends (2a) of the fiber thread length (2') are securely locked in and project out from the knitted fabric. 2. A method according to claim 1, c h a r a c t e r i z e d i n that the free fiber thread ends (2a) are deflected backward and injected between the last formed stitches (A'', A'') in two adjacent stitch rows, by exertion of a periodic deflection force on the fiber thread ends (2a). 3. A method according to claim 2, c h a r a c t e r i z e d i n that the deflection force is provided by means of a directed, periodic air jet (C). 4. A method according to claim 2, c h a r a c t e r i z e d i n that the deflection force is provided by means of a periodically generated negative pressure, whereby the fiber thread ends (2a) are drawn by suction in between said last formed stitches (A" ,A" ). 5. A method according to claim 2, c h a r a c t e r i z e d i n that the deflection force is provided by means of a periodically generated magnetic field. 6. A method according to claim 2, c h a r a c t e r i z e d i n that the deflection force is provided by means of a periodically generated electrical field of force (including static electricity). 7. A method according to claim 2, c h a r a c t e r i z e d i n that the deflection force is provided by means of a mechanical influence. 8. A method according to claims 2 - 7, c h a r a c t e r i z e d i n that the deflection force is provided by a combination of the aforementioned means, such as a directed air jet (C), negative pressure, magnetic field, electrical field of force and mechanical influence.

Inventors: LUND-ANDERSEN BIRGER, LUND-ANDERSEN, BIRGER
Applicants: LUND ANDERSEN BIRGER, LUND-ANDERSEN, BIRGER
Application year: 1992
Main classification: D04B9
IPC codes: D04B1, D04B9