GB2029465A

GB2029465A - Stringer tapes

Info

Publication number: GB2029465A
Application number: GB7922447A
Authority: GB
Original assignee: Individual
Current assignee: Individual
Priority date: 1978-07-05
Filing date: 1979-06-28
Publication date: 1980-03-19
Also published as: JPS5536380A; IT7825362A0; FR2430467B3; CA1108510A; DE2856734A1; BR7904222A; IT1097459B; BE877335A; FR2430467A1; ES482217A1

Abstract

The continuous fastener element 14 is woven into the base fabric by utilising three base fabric warp ends A, B, C and a second weft D which is woven only with these ends and is knitted by a needle 28 operating with the normal selvedge needle 27. <IMAGE>

Description

SPECIFICATION Woven tape with a row of connecting ele ments for a zip fastener and its method of manufacture The present invention relates to a woven tape with a row of connecting elements for zip fasteners and also to a method for its manufacture.

Zip fasteners generally comprise two tapes each having level with a longitudinal border a row of connecting elements intended to be mutually coupled or uncoupled by means of a slider.

The invention specifically relates to those tapes for zip fasteners having a row of connecting elements formed by a continuous e.g.

synthetic single filament which may be wound in a spiral or folded in meander fashion to provide a row of connecting elements, the filament being fixed to the border of the tape during the weaving operation of the tape itself.

One of the main problems in this type of tape for zip fasteners lies in providing a reliable and strong fastening of said spiral or meander to the border of the tape so as to prevent, during usage of the zip fastener, movement or deformation of the individual coils of the spiral or meander.

Many attempts have been made to solve this problem but the solutions proposed have not been found to be entirely successful in all respects.

A zip fastener tape is described in detail hereafter wherein the system of fastening the row of connecting elements is improved in such a way as to ensure a reliable and strong attachment and to make possible simple manufacture using ribbon needle looms.

The present invention provides a woven tape having a row of connecting elements for forming one of the two joining halves of a zip fastener and comprising a woven fabric tape having fastened to one face along an edge in the warp direction a continuous single filament providing the said row of connecting elements, the filament being fastened to the tape as the tape is woven by weaving at least three warp threads of the tape with the weft thread of the tape and with an additional weft above the filament to form loops binding the filament to the fabric.

The invention includes a woven tape with a row of connecting elements for forming one of the two joining halves of a zip fastener and comprising a tape of fabric formed by the textile interweaving of warp and weft threads, having fastened on one face along an edge in the warp direction a continuous synthetic single filament providing an array of connecting elements along the tape edge, each connecting element having a pair of arms extending therefrom lying one above the other in a plane perpendicular to the plane of the tape, the ends of the arms from each non-terminal connecting element being joined by a joining portion to arms on connecting elements on either side to form the single filament, the single filament being fastened to the tape by the weaving of three warp threads and one additional weft thread displaced from the plane of the weft thread forming the base fabric in the direction of the single filament, the three warp threads being alternately interwoven with the additional weft thread and with that forming the base fabric so as to form loops binding the single filament to the base fabric, the loops of one of said warp threads being arranged to overlie the pair of arms of each connecting element, the loops of the second warp thread being arranged to lie between the pairs of arms of successive connecting elements, and those of the third warp thread being arranged to overly the portions joining the arms or arms of adjacent connecting elements near their joining portion, the additional weft forming a warp overlying the upper arms of the connecting elements and adjoining the upper part of the loops of said warp thread. The base fabric may be a reversible or two-sided base fabric. The connecting elements may be provided by a continuous synthetic single filament wound in spiral form, or folded in meander fashion, each coil of the spiral or meander comprising a shaped end portion level with the border of the tape, two arms emerging from the end portion and which are substantially superimposed on one another in a plane generally perpendicular to said border, and a portion for joining the arm of one coil and the arm of the succeeding coil on the opposite side of the end portion.

It has been found that the binding of the single filament to the base fabric of the tape, effected by means of the warp threads alternately interwoven with the weft forming the base fabric and an additional upper weft, can be carried out so as to ensure that it is securely locked with the coils firmly held by the loops formed by said warp threads, so as to prevent any displacement or deformation thereof.

The connecting portions of the filament along the tape edge are not covered with binding threads, so that they afford perfect guidance for the slider of the zip fastener. In the following description a preferred embodiment, it will be seen that the portions of the filament which constitute the actual connecting and coupling elements, are completely free and are held in an upright position perpendicular to the border and to the upper side of the support tape, thus ensuring satisfactory operation of the zip fastener.

The method according to the invention, for the manufacture of woven tape with a row of connecting elements, comprises weaving warp threads with a weft thread to form the tape whilst supplying a continuous single filament providing a row of connecting elements to the weaving zone to lie on one face of the tape along an edge thereof and weaving at least three warp threads of the tape with the weft thread of the tape and with an additional weft thread above the filament to form loop fasten ing the filament to the tape as the tape is woven.

Preferably this method comprises weaving a tape of base fabric with warp and weft threads, feeding as a warp a continuous syn thetic single filament to overly one edge of the tape, the single filament providing a con tinuous synthetic single filament providing an array of connecting elements along the tape edge, each connecting element having a pair of arms extending therefrom lying one above the other in a plane perpendicular to the plane of the tape, the ends of the arms from each non-terminal connecting element being joined by a joining portion to arms on connecting elements on either side to form the single filament, and simultaneous binding of the single filament to the base fabric by three warp threads and one additional weft thread acting in a weaving plane above that in which works the weft for the formation of the base fabric, two of said thread warp threads being alternately raised and lowered in the shed during successive insertions of the wefts while the third one is simultaneously lowered and raised therein respectively, so as to interweave them alternately with the upper weft and with the weft forming the base fabric, the shaped single filament being caused to move forward so as to carry out one forward step for every two weft insertions, the two of the three warp threads always situated on opposite sides of the shed being fed into a zone above the pairs of superimposed arms of the elements of the shaped single filament, the third warp thread is fed into a zone displaced towards the connecting portions of the coils, the additional weft being closed in warp fashion on the opposite side to the insertion side of the weft.

The method particularly described hereafter makes possible reliable operation at high productivity on a ribbon needle loom, which only necessitates a few simple modifications with respect to a conventional loom of this type.

In the following description reference will be principally made to the case in which the continuous synthetic single filament is gener ally spiral-shaped, but it is to be understood that the invention is not restricted to this case and also covers other shapes e.g. that in which the single filament takes the shape of a meander.

The invention will be illustrated in more detail below with reference to the accompany ing drawings, in which Figure 1 shows in plan view on a greatly enlarged scale the border zone of the tape on which the spiral-shaped single filament is fastened; Figure 2 is a cross-section along the line Il-Il in Fig. 1; Figure 3 is a side view in elevation, in the direction of the arrow Ill in Fig. 1, of the tape in the process of formation in the weaving zone in one stage thereof; Figure 4 to 9 are plan views of the weaving zone in various successive stages of operation, and Figure 10 shows a detail in elevation viewed in the direction of arrow Z in Fig. 4.

Referring firstly to Figs. 1 to 3, it is evident that the tape with the row of connecting elements according to the invention comprises a base fabric, generally designated 10, formed by the textile interweaving of a weft thread 11 with a suitable number of warp threads 1 2. This base fabric 10 has a lower side and an upper side and this latter side (see in particular Fig. 2), in a border zone designated 13, has applied to it a spiral 14 formed by a continuous synthetic single filament wound so as to take the shape of a spiral.

Each coil of this spiral 1 4 comprises a shaped end portion 1 5 arranged level with the border of the tape, two arms 16, 1 7 which emerge from said end portion 1 5 and which are substantially superimposed one upon the other viewed in a plane perpendicular to the plane of the tape and to its two sides, and a portion 1 8 for connecting the upper arm 1 6 of one coil and the lower arm 1 7 of the next coil. This connecting portion 1 8 is situated on the opposite side to the end portion 1 5.

For binding and attaching the spiral 14 to the border zone 1 3 of the base fabric 10 there are provided three warp threads, respectively designated A, B and C, together with an additional weft thread D above the weft thread 11 which forms the base fabric 10.

These warp threads A, B and C are alter nately interwoven with the weft thread 11 and with the additional weft D so as to form loops for binding the spiral 14 to the base fabric 10. More particularly, the warp thread A forms loops 20 which are situated between successive coils of the spiral 14; the warp thread B forms loops 21 situated overlapping the pair of arms 16, 1 7 of each coil; and the warp thread C forms loops 22 arranged over lapping the portions 1 8 connecting the coils of the spiral 14. Furthermore, as clearly shown in Figs. 1 and 3, the additional weft thread D is fastened so as to form a warp 23 situated overlapping the upper arms 1 6 of the coils and adjacent the upper part of the loops 21 of the warp thread B.

It is evident that in this way the spiral 1 4 is entirely secured and held firmly in its position above the border zone 1 3 of the support tape.

Its single coils are thoroughly and securely locked against any displacement or deforma tion and, moreover, are kept at a constant distance apart.

It is possible to use a suitable modified ribbon needle loom for the manufacture of the tape and the simultaneous binding of the shaped spiral 14 to its border zone 1 3.

Since the loom itself does not form part of the present invention, in the examples only those members of the loom are illustrated which are indispensable for understanding the mode of operation. it is understood, however, that it is a question of a conventional ribbon loom well known in the art.

The loom comprises a double needle having a lower leg 25 and an upper leg 26 shorter than the former; the lower leg 25 of the double needle serves to insert the weft thread 11, passing through an eye provided at its end, for the formation of the base fabric, whereas the shorter upper leg 26 serves to insert the additional weft thread D, passing through an eye provided at its end (see Figs.

4 to 9). It is evident that the weft thread 11 works in a lower weaving plane and the thread D work in an upper plane. For the formation of the closing warps with the weft threads 11 and D, on the opposite side with respect to the side for inserting the wefts (on the right as shown in Figs. 4 to 9), there are provided in different planes two needles 27, 28 with tongues, both needles being mounted on a carriage 29 which is capable of reciprocating motion in the direction of the arrows in Figs. 4 to 9 above a cross member 30 of the loom. This cross member has a passage 31 (see Fig. 10) for the tape produced and in the area where the border zone 1 3 of the tape is formed this passage 31 is increased in height and is surmounted by a plate 32 which is adjustably mounted by means of a screw 33 and which has at the front a vee-shaped edge.

A tube 34 feeding the spiral 14 preformed from a continuous synthetic single filament terminates in front of this plate 32 and at the highest part 35 of the passage 31. The tube 34 is situated in the same vertical plane as the part 35 of the passage 31 and is slightly inclined with its end portion (see Fig. 3) which is suitably spaced apart from the plate 32.

The usual reed 36 is also provided for beating up the weft, the movements of which are synchronised with the movements of the double needle 25-26 and of the carriage 29.

Of course, the movements of the warp threads for forming the shed are controlled in the normal manner by healds or heddles (not shown) in the same way as the advance of the tape produced is controlled, likewise in perfect coordination with the movements of the other members of the loom.

The method for the manufacture of the tape according to the invention, with simultaneous binding of the spiral shaped single filament 14 to the border zone 13, using the ribbon needle loom briefly described above takes place in the following manner.

It has to be taken into account that the rate of advance of the tape produced and, therefore, of the single filament spiral 14 is so adjusted that said spiral advances by one step (i.e. by a distance equal to that between the centre lines of two successive coils) for every two weft insertions.

The formation of the base fabric 10 of the tape takes place conventionally by interweaving the weft 11 with a suitable number of warp threads 12.

In the following description particular attention is paid to the binding of the spiral 14 on to the upper side of the border zone 1 3 of the tape being produced.

As already mentioned, this binding is effected using three warp threads A, B and C and one additional weft thread D inserted by means of the upper leg 26 of the double needle and bound in warp 23 by means of the needle 28 with a tongue.

In a first weft-inserting operation (Figs. 3 to 6), the warp thread D is situated at the bottom of the shed in which the additional weft D is inserted.

At this point it is to be noted that all these warp threads A, B, C, independently of their position in the shed, always pass above the feeding tube 34 for the spiral 14, which tube has on its upper front edge a notch 37 for guiding these warp threads. Moreover, it is also to be noted that the warp threads A and B always arrive slightly from the left (as evident from Figs. 4 to 9) and the warp thread C slightly from the right of the tube 34, this positioning being determined by the pasage of said warp threads between corresponding teeth of the reed 36 and by the positioning of the associated control healds.

Fig. 4 shows the insertion stage of the wefts 11 and D in this first operation. It will be noted that the weft D passes between the raised warp threads A, C and the warp thread B resting on the tube 34. The double needle 25-26 advances until the wefts 11, D are hooked by the respective needles 27, 28 with tongues, after which the double needle starts its return travel, while the carriage 29 with the needles 27, 28 and the reed commence their forward movement downwards, as shown in Fig. 5. During this movement the needle 28, which withdraws the weft D, effects the insertion of the warp thread B into the space between two successive coils of the spiral.

The warp thread B, which originates from a preceding connection with the upper weft D and in the meantime the spiral 14 having moved ahead, has to surmount the advanced coil by overlapping said coil and forming the upper part of the loop 21.

Therefore, the needle 28 releases preceding stitch formed with the weft thread D. Shortly before the reed 36 effects beating up (Fig. 6), the warp threads A, B, C are acted upon by the associated healds so as to close the shed.

Subsequently, the position of the warp threads A, B, C in the shed is reversed, the threads A and C move downwards and the thread B moves upwards, thus causing the interweaving of warp threads A and C with the upper weft D, and of warp thread B with the lower weft 11 which forms the base fabric.

There now commences a second weft inserting operation (Figs. 7 to 9). The weft D is inserted between the raised warp thread B and those A and C resting on the tube 34 (Fig. 7) until it is hooked by the needle 28.

The double needle 25-26 then starts its return travel and the carriage 29 with the needles 27-28, which carriage has in the meantime been returned together with the reed 36, resumes its forward movement. During this movement, the weft D pulled by the advancing needle 28, effects the insertion of the warp thread A into the space between two coils of the spiral 14 (Fig. 8). It is to be noted that, since the spiral 14 has only moved forwards by half a step in the meantime, the warp thread A originating from the previous connection with the weft D is inserted in the same space between two coils in which, during the preceding operation, the warp thread B has been inserted.Therefore, the warp thread A does not have to surmount any coils, but its connection point with the upper weft D is stabilised in the space between the two successive coils in a position determined by the tension of the weft D and of this same warp thread A, a loop 20 thus being formed.

At the same time the weft D pulled by the needle 28 causes the warp thread C to be arranged overlapping a portion 1 8 for connecting the coils of the spiral.

Subsequently, the needle 28 releases the old stitch and just before the reed 36 carries out the beating up of the wefts (Fig. 9) the warp threads A, B, C, are acted upon so as to close the shed.

Accordingly, the position of the warp threads A, B, C in the shed is again reversed and the threads A and C move upwards, whereas the thread B moves downwards. This causes the interweaving of the warp threads A and C with the lower weft 11, and of the warp thread B with the upper weft D.

In this way, the same situation is reached as at the start of the first weft insertion operation described above.

From the foregoing it is evident that the method according to the invention can be carried out with extremely simple means and without complicating in any way the operation of the loom, the output from which can be very high.

The invention has been illustrated on the basis of one example of embodiment which may undergo various modifications without departing from the scope of this patent.

Thus, for example, as already mentioned, it would be possible to alter the spiral shape in which the continuous synthetic single filament is wound or folded, it being possible for the latter also to assume a shape similar to a meander. Moreover, if desired, the internal space of the spiral may be occupied in per se known manner by a continuous filling of reinforcing thread.

In the case of a meander-shaped single filament, said meander may comprise a series of U-shaped connecting elements joined by connecting portions alternately located at the top and at the bottom so as to join together respectively the upper arms of two successive U-elements and the lower arms of two successive U-elements. In this case it may be advantageous to bind to the base fabric of the support tape, using loops formed by the third warp thread C, the pairs of lower arms in the vicinity of the associated connecting portion, whereas the other two warp threads A and B fulfil the same functions as described above for the case in which the single filament is spiral-shaped.For the purpose of obtaining this type of binding of the warp thread C, it is necessary to act on it so that every four insertions of weft it is brought only once into the upper position of the shed, rather than cause it to change position alternately, as occurs in the case of the warp thread A. If desired, it is even possible to use the warp thread C to bind the pairs of upper arms in the vicinity of the associated connecting portion of the base fabric, but in this case, in order to avoid folding these upper arms towards the upper side of the base fabric, it may be advisable to fill the space enclosed by the meander folded into a U with a suitable filling core.

It is clear to the expert that numerous further modifications may be made according to the specific design of folding of the synthetic single filament, but still using for its fastening only three warp threads and one additional weft thread.

Claims

1. A woven tape having a row of connecting elements for forming one of the two joining halves of a zip-fastener and comprising a woven fabric tape having fastened to one face along an edge in the warp direction a continuous single flament providing the said row of connecting elements, the filament being fastened to the tape as the tape is woven by weaving at least three warp threads of the tape with the weft thread of the tape and with an additional weft above the filament to form loops binding the filament to the fabric.

2. A woven tape with a row of connecting elements for forming one of the two joining halves of a zip fastener and comprising a tape of base fabric formed by the textile interweav ing of warp and weft threads, having fastened on one face along an edge in the warp direction a continuous synthetic single filament providing an array of connecting elements along the tape edge, each connecting element having a pair of arms extending therefrom lying one above the other in a plane perpendicular to the plane of the tape, the ends of the arms from each non-terminal connecting element being joined by a joining portion to arms on connecting elements on either side to form the single filament, the single filament being fastened to the tape by the weaving of three warp threads and one additional weft thread displaced from the plane of the weft thread forming the base fabric in the direction of the single filament, the three warp threads being alternately interwoven with the additional weft thread and with that forming the base fabric so as to form loops binding the single filament to the base fabric, the loops of one of said warp threads being arranged to overly the pair of arms of each connecting element, the loops of the second warp thread being arranged to lie between the pairs of arms of successive connecting elements, and those of the third warp thread being arranged to overly the portions joining the arms or arms of adjacent connecting elements near their joining portion, the additional weft forming a warp overlying the upper arms of the connecting elements and adjoining the upper part of the loops of said first warp thread.

3. A tape as claimed in claim 1 or claim 2, whereian the single filament has the general form of a spiral or of a meander.

4. A tape substantially as hereinbefore described with reference to and as illustrated in the accompanying drawings.

5. A method for weaving a tape for forming one of the two joining halves of a zipfastener which method comprises weaving warp threads with a weft thread to form the tape whilst supplying a continuous single filament providing a row of connecting elements to the weaving zone to lie on one face of the tape along an edge thereof and weaving at least three warp threads of the tape with the weft thread of the tape and with an additional weft thread above the filament to form loop fastening the filament to the tape as the tape is woven.

6. A method as claimed in claim 5 which method comprises weaving a tape of base fabric with warp and weft threads, feeding as a warp a continuous synthetic single filament to overly one edge of the tape, the single filament providing a continuous synthetic single filament providing an array of connecting elements along the tape edge, each connecting element having a pair of arms extending therefrom lying one above the other in a plane perpendicular to the plane of the tape, the ends of the arms from each non-terminal connecting element being joined by a joining portion to arms on connecting elements on either side to form the single filament, and simultaneous binding of the single filament to the base fabric by three warp threads and one additional weft thread acting in a weaving plane above that in which works the weft for the formation of the base fabric, two of said thread warp threads being alternately raised and lowered in the shed during successive insertions of the wefts while the third one is simultaneously lowered and raised therein respectively, so as to interweave them alternately with the upper weft and with the weft forming the base fabric, the shaped single filament being caused to move forward so as to carry out one forward step for every two weft insertions, the two of the three warp threads always situated on opposite sides of the shed being fed into a zone above the pairs of superimposed arms of the elements of the shaped single filament, whereas the third warp thread is fed into a zone displaced towards the connecting portions of the coils, the additional weft being closed in warp fashion on the opposite side to the insertion side of the weft.

7. A method for weaving a tape bearing a row of connecting elements substantially as hereinbefore described with reference to and as illustrated in any one of the accompanying drawings.

8. A tape when produced by a method as claimed in any one of claims 5 to 7.

9. A zip-fastener comprising a pair of tapes as claimed in any one of claims 1 to 4 or claims 8.