GB2164362A

GB2164362A - Device on stitch-bonding machines for intensive fleece consolidation

Info

Publication number: GB2164362A
Application number: GB08522356A
Authority: GB
Inventors: Peter Offermann; Matthias Magel; Gerald Hoffmann; Eberhard Pohl; Bertram Frenzel; Dietmar Grenzendorfer
Original assignee: Kombinat Textima VEB
Current assignee: Kombinat Textima VEB
Priority date: 1984-09-10
Filing date: 1985-09-10
Publication date: 1986-03-19
Also published as: GB2164362B; FR2570096B1; IT1181711B; FR2570096A1; IT8548501A0; DD226920A1; GB8522356D0; DE3528865A1

Abstract

A stitch bonding machine is provided with a device for intensive fleece consolidation during the production of light textile fabric consisting of loose fibre and/or monofilament fleece, by the formation of perpendicular rows of stitches with fibres of the fleece. The machine is provided with knitting needles (1) adapted to be closed by sliders (2), a knocking-over comb (3) disposed behind the fibre and/or monofilament fleece, and a backing device (9) and a support means (5). At a distance from the knitting needles (1) there are disposed comb-like on a bar, means (6) which engage between the knitting needles (1) and thereby perform a lifting and/or oscillating movement in the direction of the unconsolidated fibres (7) of the fleece knit (8). The means (6) may be mounted on the bar of the backing device (9) intermediate of elements (4). <IMAGE>

Description

SPECIFICATION Device on warp knitting machines, particularly stitch-bonding machines, for intensive fleece consolidation The invention relates to a device on warp knitting machines, particularly stitch-bonding machines, for intensive fleece consolidation during the production of light textile fabric consisting of loose fibre and/or monofilament fleece, by the formation of perpendicular rows of stitches from fibre portions of the fibre and/or monofilament fleece, the machine being provided with pointed knitting needles adapted to be closed by sliders and each of which has a hook in front of its point, as well as being provided with a stationary knocking-over comb disposed behind the fibre and/or monofilament fleece and with a device for guiding the fibre and/or monofilament fleece, there being in front of the last one a backing device which extends parallel with the row of knitting needles and also a means of supporting the completed textile material, said means being disposed under the knitting needles and also under and extending along the knockingover comb.

A machine for producing like textile fabric consisting of loose fibre and/or monofilament fleece is already known (German Patent Specification 99 403). Where this prior art machine is concerned, there is associated with the knitting needlesa backing device for the loose fibre and/or monofilament fleece and a means of supporting the finished textile material, said backing device and said support means inter-engaging in comb-like fashion. The backing device is adjustable in the direction of and at right-angle to the row of knitting needles. Under the knitting needles and at a lesser distance from the knocking-over comb than the backing device, the machine is provided with a supporting means, of which the sinkers engage between the sinkers of the backing device.The backing device and the supporting means have such a relationship with one another that they form a step-like enclosing means, the gap left for passage of the fibre and/or monofilament fleece being wider above the knitting needles than below the knitting needles. The purpose of the enclosing means is to generate in the region of the knitting needles a build-up of the fibre material which will result in adequate feed of fibres to the hooks of the knitting needles.

However, the sinkers of the backing device and of the support means compress the unconsolidated fibre and/or monofilament fleece in the region of the knitting needles so that not only the number of fibres bound into the stitches but also the proportion of fibre which is not bound into the stitches increases between the individual rows of stitches.

The result therefore is a fleece knot which in terms of tearing resistance in proportion to mass area, does not show any improvement over fleece materials produced with different apparatus for mechanical consolidation with stitch forming needles.

In addition, the structural design of the supporting means and of the backing device is quite complicated in terms of size and movement.

Therefore, the object of the invention resides is providing for intensive mechanical consolidation of the fibre and/or monofilament fleece in order to increase its strength particularly in the case of light fleece knits and thus to widen the areas of application of such materials.

The invention is based on the problems of providing a device on warp knitting machines, particularly stitch-bonding machines, for producing light textile fabric consisting of loose fibre and/or monofilament fleece, by which a preferably thin layer of material can be interlinked right though.

According to the invention, this problem is resolved in that under and at a distance from the row of knitting needles there are disposed comblike on a bar, means which engage between the knitting needles and thereby perform a lifting and/ or oscillating movement in the direction if the unconsolidated fibres of the fleece knit.

By the use of these means which are disposed comb-like in accordance with the invention, the fibres which, in the case of the prior art fleece knits, are disposed between the rows of stitches and which contribute only a very small share towards the strength of the material, are picked up and lifted over the points of the knitting needles so that in the subsequent working cycle, they are once again picked up by the knitting needles and are additionally consolidated. Thus, the share of fibres bonded into the stitches is substantially increased and with it the strength of the fleece knit.

The invention will be explained in greater detail with reference to an example of embodiment shown in the accompanying drawings, in which: Figure 1 is a diagrammatic cross-section through the stitch-forming zone of a stitch-bonding machine, and Figure 2 is a plan view of Figure 1.

Figure 1 shows diagrammatically the stitch-forming zone of a stitch-bonding machine for producing light textile fabric consisting of loose fibre and/or monofilament fleece and provided with reciprocatingly movable knitting needles 1 which have, for example, the form of sliding needles. For opening and closing the needle hooks 10, closure wires 2 are used. The closure wires 2 close the hooks 10 when the knitting needles 1 emerge rearwardly from the fibre and/or monofilament fleece 7 and pull the fibre loops 11 entrained thereby out of the fleece through the fibre loops present on the knitting needles 1 and formed in the previous operation. In this way, the fibre and/or monofilament fleece 7 becomes interlaced to form a fleece knit 8 by means of fleece stitches 12 provided on its right side and created from the fibres of the fleece 7.

The fibre and/or monofilament fleece 7 and the finished fleece knit 8 are, in the region of the stitchforming zone, passed between a rigid knockingover comb 3 disposed at a right-angle to the knitting needles 1 and the backing device 9 which is constituted by the laying-in sinkers 4 disposed opposite the knitting needles 1, and the support rail 5 under the knitting needles 1.

Likewise disposed under and at a distance from the row of knitting needles 1 and disposed comblike on the bar 9 are means 6 which engage between the knitting needles and perform thereby a lifting and/or oscillating movement in the direction of the unconsolidated fibre portions 7. The means 6 consist, for example, of wires or sinkers.

At the commencement of a new stitch-forming cycle, the knitting needles 1 are at the rear dead centre position in the knocking-over comb 3 and in their hooks 10 is a half-stitch 11 consisting of fibre bundles. Upon the forwards movement of the knitting needles 1, the closure wire 2 moves farther back and the previously closed needle hook 10 opens, so that when the knitting needles 1 penetrate the fibre and/or monofilament fleece 7, the half-stitch 11 can slide onto the needle shank. In this phase, means 6 engage below the knitting needles 1 between the perpendicular rows of stitches formed in the preceding operating cycle and, by a lifting and/or oscillating movement, lift the unconsolidated fibre portions disposed between the perpendicular rows of stitches over the points of the knitting needles 1. This prevents the fibre portions disposed between the rows of stitches becoming forced in the direction of the fleece knit 8 when the knitting needles 1 pierce the fibre and/or monofilament fleece 7.

Once the knitting needles 1 have reached the forward dead centre position, means 6 move in the direction of pull-off of the finished fleece knit 8, release the lifted fibre portions and subsequently assist the pull-off process. The lifted fibre portions can, during the rearwards movement of the knitting needles 1, be picked up by the latter and then participate in stitch-formation. As a result, in the production of light fleece knits, the greatest possible proportion of fibres will participate in stitch-formation and thus the strength of such fleece knits can be substantially increased.

Claims

1. Device on warp knitting machines, particularly stitch-bonding machines, for intensive fleece consolidation during the production of light textile fabric consisting of loose fibre and/or monofiiament fleece, by the formation of perpendicular rows of stitches, the machine being provided with pointed knitting needles adapted to be closed by sliders and each of which has a hook in front of its point, with a knocking-over comb disposed behind the fibre and/or monofilament fleece, and a backing device and a support means, characterised in that below and at a distance from the knitting needles (1) there are disposed comb-like on a bar (9), means (6) which engage between the knitting needles (1) and hereby perform a lifting and/or oscillating movement in the direction of the unconsolidated fibres (7) of the fleece knit (8).

2. Device according to Claim 2, characterised in that the means (6) consist for example of wires or sinkers.

3. Device according to Claim 1 and 2, characterised in that the means (6) are combined with fibre lay-in sinkers (4).

4. Device according to Claim 1 to 3, characterised in that the means (6) are disposed between the needle points instead of laying-in sinkers (4).

5. Device acording to Claim 1 to 4, characterised in that during piercing of the fibre fleece (7) by the knitting needles (1), the means (6) are disposed above the knitting needles (1) during piercing of the fleece (7) by the knitting needles (1) against the direction of material flow and are below the knitting needles (1) when the fibres are being picked up by the knitting needles (1) in the direction of material flow.

6. Device on warp knitting machines, particularly stitch-bonding machines, for intensive fleece consolidation as claimed in Claim 1, substantially as described herein with reference to and as ilustrated by the example shown in the accompanying drawings.