EP0668945B1 - Device on a warp knitting machine for crocheting an elastic band with a coating and possibly for crocheting picots, and an elastic band produced with this device - Google Patents

Abstract

PCT No. PCT/EP93/02890 Sec. 371 Date Jul. 7, 1995 Sec. 102(e) Date Jul. 7, 1995 PCT Filed Oct. 19, 1993 PCT Pub. No. WO94/11554 PCT Pub. Date May 26, 1994A device on a warp knitting machine for crocheting an elastic band with a coating and an elastic band made with this device. The band may also have picots at its edges, that is small loops. The device is intended to facilitate the production of very fine bands with a distribution of more than eight and especially twelve needles per centimeter of machine width and even more if possible. The coating should be patternable. The coating may be produced on only one or on both sides of the strip. The device has crochet hooks (4), a cuttler (80) to feed skeins of rubber-elastic threads (14) and a cuttler (20) to feed skeins of warp threads (22).

Description

The invention first relates to a device on a warp knitting machine (crochet machine) for crocheting a textile tape, the device having the crochet tools specified in the preamble of claim 1.

This device is said to be able to produce a particularly fine, rubber-elastic band which is provided with fluff on at least one broad side. Tapes of this type are said to be suitable for underwear, in particular brassieres, and to have a very soft surface, namely the fleece, at least on one broad side.

The device is intended to enable the production of very fine strips, namely with a pitch of more than eight, in particular twelve or more, needles per centimeter of machine width. The fleece should be able to have a pattern, the pattern being able to be varied to a large extent. The aim is to create the possibility of producing a patterned fleece on only one side of the hinge or on both sides of the hinge.

Such elastic bands can also be produced by weaving. For this, however, it is necessary that the rubber-elastic threads running in the longitudinal direction of the tape are wound before the actual weaving process, which requires additional manufacturing costs.

In the context of the present invention, this additional spinning is to become superfluous, and the rubber-elastic threads are also to be knitted as part of the crochet process. In this way, the manufacturing costs can be reduced by about 30% compared to weaving.

From the documents EP-A-0 210 518 and GB - A-2 012 828 a device according to feature a, b, c, f, g of claim 1 is known, which is used to produce a pile loop knitted fabric, that is, a knitted fabric with very wide protruding loops, such as bath towels. With devices of this type, it is not possible to achieve the desired high fineness of the tape, namely more than eight, in particular more than twelve crochet elements per centimeter machine width, because pole loop holders and sinkers between the Crochet needles must be performed, but have such widths that the crochet hooks can no longer be arranged side by side in the desired density. The perforated needles for feeding the weft threads have correspondingly large mutual distances.

The above-mentioned requirements are met by the invention according to claim 1. (The terms defined in the claims are also used below.)

Expressions such as "front", "rear", "right", "left" refer to the usual location of an observer in front of such a crochet machine (B in FIGS. 1 to 3, 5 and 6).

From an older, unpublished German patent application P 41 31 809.9 (de) by the same applicant, it can be seen how crochet hooks are clamped in a needle bar, moved back and forth with it, how coulters of warp threads are fed from the front by sets of piercing needles, coulters elastic threads are moved from above by combs and a front and a rear single weft thread, each with a tube, transversely to a group of elastic threads, right-left-right.

The high fineness of the tape can be achieved by arranging the above-mentioned and other crochet elements in the desired fineness, i.e. more than eight, but in particular twelve or more crochet elements per centimeter of machine width, with up to 16 crochet elements per centimeter being sought. EP-A-0 266 481 - BERGER (ep) shows how perforated needles can be arranged in the necessary number per centimeter machine width.

To form a fluff on the front broad side of the belt (seen from viewer location B), a weft share laying device can be arranged according to the invention in front of the web for the sheets of rubber-elastic threads. Both in front of and behind the path of the elastic thread sheets there is a single weft laying device, that is to say a device which places a single weft thread or a bundle of parallel weft threads across the entire width of the sheet of elastic threads. The weft coulter laying device can be moved back and forth, and is arranged to be displaceable sideways, so that, depending on which of the weft needles of a set of weft threads, a desired fluff pattern can be produced.

Another aspect of the invention relates to an elastic band which is crocheted on one of the devices claimed, has a high fineness and is provided with a fleece on at least one of its broad sides.
Further developments of both parts of the invention result from the subclaims.

If the tape should also have a fleece on its back, a rear weft coulter laying device can be provided instead of a rear single weft laying device. If, on the other hand, the band is to be smooth on its back, that is to say without fluff, there is only a single-weft laying device in the known manner at the back, which leads one or more weft threads over the entire range.

In view of the desired high fineness of the elastic band, the needles of the weft share laying device (s) cannot reach between the heads of the crochet hooks. The heads of the front weft coulter laying device temporarily grip from the front and above between the warp threads of the warp thread sheet extending from the warp thread perforating needles to the stitch formation point. The droplets of front weft threads are then taken from the warp threads to the heads of the crochet hooks.

If a rear weft coulter laying device is used, the heads of the perforated needles are brought as close as possible to the stitch formation point from behind and above with the crochet hooks withdrawn, namely to a position on the upper edges of a knock-down rail and a retaining rail, between which the finished crocheted elastic band is pulled down. The back weft threads are gripped by the heads of the crochet hooks and taken away.

The elastic band can have small loops ("picos") on one or both of its edges, which are produced in a known manner.

Figur 1

ist eine linke Seitenansicht einer Häkelmaschine mit Häkelwerkzeugen zur Erzeugung eines elastischen Bandes mit vorderem Flausch und Picos an den Rändern.

Figur 2

zeigt in einer gleichartigen Darstellung die Häkelwerkzeuge für die Erzeugung eines elastischen Bandes mit beidseitigem Flausch. Eine Vorrichtung zur Erzeugung von Picos ist zur Vereinfachung hier nicht dargestellt.

Figur 3

ist eine Draufsicht auf einige der Häkelwerkzeuge nach Fig. 1.

Figur 4

zeigt in Vorderansicht einen Teil einer Kettengliedersteuerung.

Figur 5

ist eine Schrägansicht von links oben auf einige der Häkelwerkzeuge nach Figur 1 bei nach vorn geschobenen Häkelnadeln.

Figur 6

ist eine Schrägansicht von rechts oben auf einige der Häkelwerkzeuge nach Figur 1 bei maximal weit zurückgezogenen Häkelnadeln.

Exemplary embodiments with further features of the invention are described below with reference to the drawings.

Figure 1

is a left side view of a crochet machine with crochet tools to produce an elastic band with front loop and picos on the edges.

Figure 2

shows in a similar representation the crochet tools for producing an elastic band with double-sided fleece. A device for generating picos is not shown here for simplicity.

Figure 3

3 is a top view of some of the crochet tools shown in FIG. 1.

Figure 4

shows a part of a chain link control in front view.

Figure 5

is an oblique view from the top left of some of the crochet tools of Figure 1 with the crochet hooks pushed forward.

Figure 6

is an oblique view from the top right of some of the crochet tools of Figure 1 with the crochet hooks pulled back as far as possible.

The viewer's reference location B is on the right in FIGS. 1, 2 and 5, at the bottom left in FIG. 6 and at the bottom in FIG. 3.

Flocks of rubber-elastic threads 14 (made of natural or synthetic rubber) are guided from above with strong stretching (about 100%) between the teeth of combs 16 to a stitch formation site 6. The finished crocheted band 8 is pulled down under the same stretch, in a narrow gap between a knock-off rail 10 and a retaining rail 12.

Figure 1 shows, seen from the left, a needle bar 2, in the crochet hooks 4 (carabiner needles) with heads 5 are clamped. With the needle bar, the crochet hooks can be moved from their extremely rear position shown in FIGS. 1 and 2 between tines 3 of a knock-off rail 10 and the rubber-elastic threads 14 to a position according to FIG. 5 and back again.

A group of warp threads 22 is guided from a warp beam 24 through the heads 28 of warp thread perforated needles 26 to the stitch formation point 6. There are two sets of perforated needles 26 each rigidly attached to a warp laying rail 29 in such a way that their heads engage between one another, as described in EP-A-0 266 481 - BERGER. The warp needles are moved back and forth (seen from location B). In addition, the needles right-left-right are offset by about the distance between two crochet hooks 4 so that the heads 5 of the crochet hooks are wrapped in the warp threads.

A rear and a front single-weft laying device 30h and 30v serve to feed a front weft thread, which is referred to here as a "single weft", which is either a single thread or a bundle of individual threads lying next to one another. Which are arranged behind or in front of the web for one of the coulters of the elastic threads 14. These single-weft laying devices each have a weft guide 34h, 34v, which firmly engages around a laying rail 38h, 38v with a hook 39h, 39v and is controlled by this. It has at its lower end a tube 36h, 36v through which the single weft thread 32h, 32v is guided back and forth, above the warp threads 22 and transversely to them near the stitch formation point 6. The tubes follow the weft thread on one top curved path from the left edge of the sheet of warp threads and rubber elastic threads to their right edge and back, so that it is crocheted with.

In order to produce a fluff on the front of the belt 8, a set of weft threads 56v is fed from a front weft laying device 50v, namely through heads 53v of perforated needles 52v which are attached to a weft laying rail 54v. Figure 5 shows further details. Preferably, these perforated needles 52v are also arranged like the perforated needles 26, ie in the form of obliquely interlocking perforated needle packages. The perforated needles 52v are shown in Fig. 1 in two different positions, in an upper position in which the front weft threads 56v run obliquely from the front up to the stitch formation point 6 and in a lower position in which the heads of the Weft piercing needles 53v have been passed through the array of warp threads 22. From there, the weft threads are taken along by the warp threads when the heads 5 of the crochet hooks are looped around and integrated.

If the elastic band to be crocheted only on its one, z. B. front broadside with a fleece, it must be prevented that it later curls because of the asymmetry of the weft threads. For this purpose, the rear single-weft laying device 30h in this case does not feed a single weft thread, but rather a bundle of parallel weft threads. This should not be confused with a family of weft threads such as those used by a weft-laying device, e.g. B. 50h is supplied.

If a fleece is also to be produced on the rear side of the elastic band, a rear weft coulter laying device 50h can be arranged instead of the rear single weft laying device 30h, which leads a coulter of rear weft threads 56h to the stitch formation point according to FIG. Figure 2 shows the position in which the rear weft needles 52h are brought as far as possible to the stitch formation point 6. From this position, too, they are involved, with their previous right-left shift deciding between which crochet hooks this happens.

With the use of front and rear weft coulter laying devices, elastic bands with fleece on both sides can be crocheted.

FIG. 3 shows the needle bar 2 from above and the crochet hooks 4 clamped in it, as well as the weft thread guides 34h, 34v with tubes 36h, 36v for the rear and front individual weft threads, with somewhat changed dimensions. The combs 16 for the rubber-elastic threads are attached to a laying rail 80.

The front weft perforating needles 52v are fastened to the front weft laying rail 54v and the perforating needles 26 for the warp threads to the associated warp laying rail 29.

For the sake of simplicity, FIG. 3 shows only one set of crochet tools. However, many such sets are arranged side by side across the machine width in a known manner.

A chain link drum 82 is indicated in FIG. Chains run around the drum to steer each of the laying rails sideways. Only one chain is shown which has links 84 and 86 for controlling the front share coulter bar 54v. Depending on the (radially measured) height of the chain links, the laying rail 54v for the front weft needles 52v is moved sideways via a scanning roller 88. It is hereby achieved that the front weft threads are moved over one or more warp threads, depending on the desired pattern of the fluff. The pattern is achieved in a known manner by using higher or lower chain links 84, 86.

The same applies to the rear weft thread guide 54h, which is not shown in FIG. The warp thread laying rail 29 and the rear and front laying rail 38h, 38v for the single weft threads are controlled by other chains. The warp thread laying rail 29 is shifted right-left-right, but only by small distances, namely essentially the distance between the centers of two adjacent crochet hook heads 5.

FIG. 5 shows a part of the crochet tools with crochet hooks 4 advanced to the maximum. It also shows one of many sets of front warp thread piercing needles 26 to be arranged next to one another, but only a set of warp threads 22. The warp threads run from the heads 28 of the piercing needles 18 to the stitch formation point 6. The tube 36h can be seen in its extreme left position. It feeds the rear weft 32h. One recognizes the hook 39h of the weft thread guide 34h, which engages around its (the rear) laying rail 38h and is moved with this right-left-right.

The front single-shot laying device 30v and the rear weft share laying device 50h have not been shown in FIGS. 5 and 6 for the sake of a better overview.

It can be seen in FIGS. 5 and 6 that a group of front weft threads 56v is guided from above to the heads of the front weft thread needles 52v. The sets of front weft piercing needles 52v are attached to the lay rail 54v which runs (to the right in Figure 5) to the chain link drum.

Function of the crochet tools described so far

A group of rubber-elastic threads 14 is guided from above between the tines of one of the combs 16 to the stitch formation point 6. The crochet hooks 4 are moved back and forth with the needle bar 2 between the tines 3 of the knock-off rail 10 and reach through between the rubber-elastic threads. The warp thread perforated needles 26 feed the warp threads 22 from the front and ensure, through a sideways offset, that the heads 5 of the crochet hooks are looped around. The rear weft guide 34h places a rear weft from right to left and back across the family of the elastic threads 14. The front weft needles 52v reach obliquely downwards and above between the family of warps 22 so that the front wefts 56v from diagonally below to the stitch formation point 6 and put together with the warp threads in the heads of the crochet hooks. In a manner known per se, stitches are formed and the finished elastic band 8 is pulled off downward, the elastic threads being stretched as far as the warp threads 22 allow. Later, when the elastic band is relieved, it contracts in the longitudinal direction. The desired fleece then results from the fact that the front weft threads 52v, which are initially lying flat, now form loops.

The structure of the fluff can be varied, firstly by the number of wefts 56v used. In general, not each of the weft needles 52v feeds a weft. Rather, you can release other needles according to the desired pattern between weft needles. Furthermore, the extent and lateral length of the chain links used can control the extent of the lateral movement of the laying rails and the weft needles.

If there is also a rear weft coulter laying device 50h, an elastic band can be crocheted which has a fleece on both broad sides, the fleece patterns on both sides being the same or different.

If fluff is not to be produced on any hinge side, then instead of the front and rear weft coulter laying devices 50v, 50h, front and rear single-weft laying devices 30v and 30h are used.

Pico device and its function

If the elastic band should have picos (small loops) on one or both edges, then a right and a left pico device 70R and 70L are used, as is only shown in FIGS. 1 and 6. Each of the two pico devices has a so-called Kraller 74R and 74L, namely a mandrel that tapers at its upper end in FIG. 1 and is curved to the left. Each claw is fixed in a holder 76R, 76L and sits with this holder in a rotationally fixed manner on a drive shaft 72R, 72L. The two drive shafts are also controlled by a chain of the chain link drum, namely an initially generated right-left movement is converted into pure pivoting movements of the drive shafts 72R and 72L by mechanical deflection in a manner known per se.

If only Picos is to be produced on one edge of the band, only one of the claws is activated, while the other remains pivoted out, as is the case with the claw 74L in FIG. 1 or removed. If the front weft thread 32v is guided all the way to the right, the claw 74R is pivoted into its effective position shown in FIG. 1 to produce a pico. The front weft thread 32v is, as usual, moved to the left by the front weft thread guide 34v across the width of the warp thread sheet and is crocheted. The right claw is then swung out. A pico remains on the right edge of the ribbon.

The same applies to the left edge of the tape, where the Kraller 74L can also generate picos.

Picos can be generated either on the left or only on the right edge or on both edges, depending on the control of the drive shafts 72R and 72L, the picos are generated at regular or irregular small or large intervals.

REFERENCES

B

Location of the viewer

2nd

Needle bar

3rd

prong

4th

Crochet hook

5

Crochet needle head

6

Stitch formation site

8th

elastic band

10th

Tee rail

12th

Restraint rail

14

elastic threads

16

Comb

20th

Laying device for warp thread coulter

22

Warp threads

24th

Warp beam

26

Warp needle

28

Head of the warp needle

29

Warp thread guide

30h, 30v

rear, single shot launcher

32h, 32v

rear, front weft

34h, 34v

rear, front weft guide

36h, 36v

rear, front tube

38h, 38v

rear, front guide rail for single shot

39h, 39v

rear, front hook

50h, 50v

rear, weft share laying device

52h, 52v

rear, front needles for weft share

53h, 53v

back, front heads of the needles

54h, 54v

rear, weft share laying rail

56h, 56v

rear, front weft threads

70L, 80R

Pico device

72L, 72R

Drive shaft for left and right claws

74L, 74R

left, right claw

76L, 76R

left, right holder

80

Laying device for rubber elastic threads

82

Chain link drum

84, 86

Chain link

88

Scanning roll

Claims (8)

1. A device on a warp knitting machine (crocheting machine) for crocheting a textile band (8), said device having the following crocheting tools:

   a) crochet needles (4) clamped in a needle bar (2) with which they are movable forwards and backwards,

   b) a laying device (20) for arrays of warp threads (22) having a warp thread laying bar (29) capable of forwards and backwards movement and side shifting, having carriers for sets of warp thread eye needles (26),

   c) a front and/or a rear single weft laying device (30v, 30h) wherein to produce a particularly fine elastic band, provided with a fleece on at least one broadside, a combination of the following features is provided:

   d) more than eight crocheting members are provided per centimeter of machine width.

   e) a laying device (80, 16) is provided for feeding arrays of elastic threads (14) greatly stretched,

   f) two sets each of eye needles (26, 52v, 52h) are fixedly arranged at an acute angle to each other so that the heads of the one set interengage with those of the other set,

   g) to form a fleece on at least one side of the path described by the arrays of elastic threads (14) a weft array laying device (50v, 50h) having sets of weft thread eye needles (52v, 52h) is provided for feeding an array of weft threads (56v, 56h).
2. The device as set forth in claim 1, characterized in that at least twelve crocheting members are provided per centimeter of machine width.
3. The device as set forth in claim 1 or 2, characterized in that for forming a fleeceless band side a single weft laying device (30v, 30h) is provided which feeds at least one weft thread.
4. The device as set forth in claim 1, characterized in that each of said weft array laying devices (50v, 50h) has a weft thread laying bar (54v, 54h) which is controlled shiftable to and fro in its longitudinal direction with respect to the mesh forming spot (6) and is controlled pivotable about its longitudinal axis.
5. The device as set forth in claim 4, characterized in that by such an arrangement and guide of said front weft array laying device (50v) the heads (53v) of its weft thread eye needles (52v) engage from the front and above between the warp threads of the warp thread eye needles (26) of the array of weft threads (22) running to the mesh forming spot (6).
6. The device as set forth in claim 4, characterized in that by such an arrangement and guide of said rear weft array laying device (50h) the heads of its weft thread eye needles (52h) are advanced to the vicinity of the mesh forming spot (6) from the rear and above when said crochet needles (4) are retracted.
7. A rubber band characterized in that

   a) it is crocheted by using a device on a weft knitting machine (crocheting machine) having crochet tools as set forth in any of the preceding claims,

   b) it has a fineness corresponding to more than eight, particularly twelve or more elastic threads per centimeter of machine width,

   c) it is provided with a fleece of an array of additional weft threads on at least one of its broadsides,

   d) single weft threads laid from a single weft laying device (30v, 30h) run across the entire width of the band.
8. The rubber band as set forth in claim 7, characterized in that it is provided with looplets ("picots") on at least one of its edges.

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