LOADING YARNS INTO A TEXTILE MACHINE

Abstract

The invention relates to an apparatus for presenting threads for loop-forming tools, arranged in at least one row, of a textile machine having a thread guide apparatus having at least one rotary element (4, 5, 20, 21, 30, 31, 40, 41) having at least one thread guide (20a, 20b, 21a, 21b 30a, 30b, 40a, 40b), said thread guide apparatus being configured to lay a thread back and forth in two directions (HI, HR) in each case in front of a row of the tools in an entire stroke range (BG). The thread guide apparatus has at least two rotary elements (4, 5) arranged as a pair, wherein the rotary elements (4, 5, 20, 21, 30, 31, 40, 41) of a pair are arranged eccentrically with respect to one another and one above another in the axial direction, and wherein the rotary elements (4, 5) of a pair are drivable in opposite directions of rotation (R1, R2). Each rotary element (4, 5, 20, 21, 30, 31, 40, 41) has at least one thread guide (4a, 4b, 4c, 5a, 4b, 4c, 20a, 20b, 21a, 21b, 30a, 30b, 40a, 40b), configured as a driver element, for laying the thread in one of the directions (HI, HR).

Claims

1. An apparatus for loading yarns into at least one row of stitch-forming tools of a textile machine, comprising a pair of yarn loader each having a pair of rotor rotating in opposite directions about a common axis and one axially above the other, at least one yarn guide, on each of the rotors operable to lay a yarn back and forth in two directions along a full machine width in front of the row of tools, being formed as a driver element for laying the yarn in a respective one of the directions.

2. The device according to claim 1, further comprising: a feeding device that supplies the yarn that is laid in a respective one of the directions to the tools.

3. The device according to claim 1, further comprising a retaining device with two retaining elements that are near reversal points of the yarn spaced apart by the full machine width, the retaining devices each receiving the yarn laid by the yarn loader in a respective one of the directions and supplying it to the tools.

4. The device according to claim 1 wherein the rotors each have at least two yarn guides.

5. The device according to claim 1, in that wherein the yarn loader comprises a number of pairs of rotors, the pairs being side by side with each pair laying the yarn over a respective stroke range corresponding to the full machine width divided by the number of pairs.

6. A textile machine comprising at least one row of stitch-forming tools and having an apparatus according to claim 1 for each row of tools.

7. A method for loading yarns into at least one row of stitch-forming tools of a textile machine having a yarn loader having at least one pair of rotors rotatable about a common axis one above the other and each having at least one yarn guide the method comprising the steps of: rotating the rotors in opposite directions of rotation; and engaging the yarn guides as driver elements with the yarn being to lay the yarn in a respective one of the directions by each rotor.

8. The method according to claim 7, further comprising the step of: feeding the yarn laid in one direction by a feeding device to the tools.

9. The method according to claim 7, further comprising the step of: laying the yarn laid in the directions by two respective retaining devices that are near reversal points of the yarn spaced apart by the full machine width and thereby supplying the yarn to the tools.

10. The method according to any one of claim 7 wherein the yarn is laid by one respective pair of a number of pairs, each with two rotors of the yarn loader, over a stroke range that corresponds to the full machine width divided by the number of pairs.

Description

[0034] The invention will be explained in further detail on the basis of examples that are illustrated schematically in the drawing. The illustrated examples relate to textile machines according to the invention that are warp-knitting machines with an apparatus according to the invention for laying yarns for a textile machine, specifically for loading weft yarns for the warp-knitting machine. In the drawing:

[0035] FIG. 1 is a schematic view of the principle of a warp-knit fabric with a weft yarn;

[0036] FIG. 2a is a schematic perspective view of a pair of rotors of a first device according to the invention for loading yarns in a first position;

[0037] FIG. 2b is a schematic view corresponding to FIG. 2a in a second position;

[0038] FIG. 3 is a schematic view of a textile machine according to the invention embodied as a warp-knitting machine with the apparatus according to the invention of the first example;

[0039] FIG. 4 is a view of the principle of another warp-knit fabric with a weft yarn; and

[0040] FIG. 5 is a schematic view of three pairs of rotors of a second device according to the invention for loading yarns.

FIRST EXAMPLE

[0041] In the first example, the textile machine is a warp-knitting machine with an apparatus for loading yarns as weft yarns in front of a row of knitting tools.

[0042] FIG. 1 is a schematic illustration of a section of a narrow strip of a warp-knit fabric that can be produced by the warp-knitting machine. The warp-knitting machine is embodied, for example, as an RL Raschel warp-knitting machine with one row of knitting tools, with RL meaning right-left stitching. In the illustrated example, the warp-knit fabric is composed of five stitch-forming warp yarns 1 and one weft yarn 2. FIG. 1 shows a cutaway row of stitches and four complete rows of stitches with three weft reversal points 3.

[0043] The apparatus for loading the weft yarn for the knitting tools has a yarn loader. FIGS. 2a and 2b show the principle of the yarn loader in a perspective view. It lays the weft yarn 2 back and forth in two directions HI, HR in the region in front of the knitting tools of the warp-knitting machine that extend over a full machine width B indicated in FIG. 2b.

[0044] The yarn loader has two rotors 4 and 5 provided as a pair. The rotors 4 and 5 are in front of a row of knitting tools, with knock-over bits 6 and five latch needles 7 of the knitting tools of the warp-knitting machine being visible in FIGS. 2a, 2b. The rotors 4 and 5 of the pair are one above the other in the direction of their common axis D shown in FIG. 3. The rotors 4 and 5 of the pair can be driven in opposite directions of rotation R1, R2. In the example shown in FIGS. 2a, 2b, the rotor 4 is above the rotor 5. In this example, the axis of rotation of the two rotors 4 and 5 is parallel to the direction of movement RZ of the latch needles 7 and thus perpendicular to the row of knitting tools.

[0045] Each rotor 4 and 5 has three yarn guides 4a, 4b, 4c, 5a, 5b, 5c that are driver elements for laying the weft yarn 2 in one of the directions HI, HR.

[0046] In a first position shown in FIG. 2a, the warp yarns 1 coming from above in FIGS. 2a and 2b are guided around the latch needles 7 to form a next stitch above the latch 7a of the latch needle 7. Each of the warp yarns 1 forms a stitch beneath the latch 7a of the latch needle 7 into which a knit portion 2G of the weft yarn 2 running from left to right is already incorporated in FIG. 2a. In FIG. 2a, the weft yarn 2 is laid by the yarn guide 4a of the rotary member 4 in the direction HI in front of two latch needles 7 starting from the weft reversal point 3.

[0047] FIG. 2b shows the transfer of the weft yarn 2 from the yarn guide 4a of the upper rotor 4 to the yarn guide 5a of the lower rotor 5. The latch needles are in a knock-over position.

[0048] FIG. 3 shows a schematic and not-to-scale illustration of the warp-knitting machine with the apparatus for loading the weft yarn 2 in front of the knitting tools, particularly as a schematic vertical cross section. The yarn loader with the rotors 4 and 5 are in front of the knitting tools 7 of the knitting machine. The position of the rotors 4 and 5 corresponds to that of FIG. 2a.

[0049] One of the latch needles 7, one of the knock-over bits 6, one of the guide needles 8, and one of the warp yarns 1 of the knitting tools are shown. The warp yarns 1 are guided through the guide needles 8 to the latch needles 7. The weft yarn 2 is guided from a bobbin 9 to the yarn guide 4a of the rotor 4 that lays it in front of the latch needle 7 beneath the latches 7a.

[0050] The rotors 4 and 5 of a pair are provided such that the rotating yarn guides 4a, 4b, 4c, 5a, 5b, 5c cross the yarn path of the weft yarn 2 from the bobbin 9 to the knitting tools.

[0051] The warp-knitting machine is indicated by a rear side wall 10 and a base 11. The warp-knitting machine has a pair of rollers 12 and a take-up roll 13 for winding up the warp-knit fabric KG produced in the take-off direction P downstream of the knitting tools (left side in FIG. 3).

[0052] During operation, the weft yarn 1 is laid back and forth by the yarn loader in the region in front of the knitting tools of the warp-knitting machine in two directions HI, HR that extend over the complete stroke width B.

[0053] The rotors 4 and 5 of the yarn loader that are provided as a pair are axially one above the other and driven in opposite directions of rotation R1, R2. The weft yarn 2 is respectively laid by the yarn guides 4a, 4b, 4c, 5a, 5b, 5c that are guide arms in one of the directions HI, HR. That is, in the yarn path of the weft yarn 2 from the bobbin 9 to the knitting tools, the weft yarn 2 is grasped, laid back and forth, and thus presented to the knitting tools by the rotating yarn guides 4a, 4b, 4c, 5a, 5b, 5c of the rotors 4 and 5 of a pair.

[0054] The weft yarn 2 is laid by the yarn guides 4a, 4b, 4c of the rotor 4 in the direction HI (from right to left in FIGS. 2a, 2b) and by the yarn guides 5a, 5b, 5c of the rotary member 5 in the direction HR (from left to right in FIGS. 2a, 2b). The weft yarn 2 is guided alternately by the yarn guides 4a, 4b, 4c of the rotor 4 and the yarn guides 5a, 5b, 5c of the rotor 5. As is shown in FIG. 2b, the weft yarn 2 is taken over by the yarn guide 5b from the yarn guide 4a for this purpose, for example.

[0055] In an alternative example, the axis of rotation of the two rotors extends at an acute angle relative to the direction of movement RZ of the latch needles 7.

[0056] In an alternative example, the two rotors of a pair are provided eccentrically parallel to the row of knitting tools.

[0057] In an alternative example, the warp-knitting machine is embodied as an RR Raschel warp-knitting machine with two rows of knitting tools. The warp-knitting machine has an apparatus for loading a weft yarn for each of the two rows.

Second Example

[0058] The second example corresponds to the first example except for the features described below.

[0059] FIG. 4 shows a schematic illustration of a section of a narrow strip of a warp-knit fabric KG. In the illustrated example, the warp-knit fabric KG is composed of nine stitch-forming warp yarns 1 and one weft yarn 2. FIG. 1 shows a cutaway row of stitches and nine complete rows of stitches. In the upper five rows of stitches with five weft reversal points 3, the weft yarn 2 is guided around all of the stitches of a row. In the lower four rows of stitches, the weft yarn 2 is guided only by a portion of the stitches, namely by four stitches, with two inner weft reversal points 3i being formed in addition to an additional, outer weft reversal point 3.

[0060] FIG. 5 shows the principle of a yarn loader of the device of the second example. The yarn loader comprises a number N of three pairs, each with two rotors 20, 21, 30, 31, 40, 41, each of which has two yarn guides 20a, 20b, 21a, 21b, 30a, 30b, 31a, 31b, 40a, that are guide arms 40b, 41a, 41b. The three pairs are side by side along an entire stroke range BG. Each pair is lays the weft over a partial stroke range BT. The stroke range BT corresponds to the full machine width BG divided by the number N of the pairs, i.e. divided by 3.

[0061] The stroke range BT of a pair of rotary members 20, 21, 30, 31, 40, 41 is 3 cm in this example. The full machine width BG is 9 cm, for example.

[0062] During operation, the weft yarn 2 is laid by one pair of three juxtaposed pairs, each with two rotors 20, 21, 30, 31, 40, 41, over a stroke range BT, which corresponds to the full machine width BG divided by the number N of pairs. This is shown for the top five rows of stitches of the warp-knitted fabric KG shown in FIG. 4.

[0063] In the lower four rows of stitches of the warp-knit fabric KG shown in FIG. 4, the weft yarn 2 is laid by the right pair of rotary members 20, 21 over the right three stitches and by the middle pair of rotary members 30, 31 over one stitch.

[0064] In an alternative, the stroke range of a pair of rotary members is from 0.5 cm to 50 cm.

[0065] In an alternative of a warp-knit fabric, multiple layers of weft yarns are provided.

[0066] In that case, multiple weft yarns are moved back and forth simultaneously by a plurality of pairs of rotors of the yarn loader and fed one above the other to the knitting tools.

[0067] Such warp-knit fabrics can be used in lightweight construction, for example for composite structures in wind turbines or in automobiles.

TABLE-US-00001 List of Reference Symbols 1 warp yarn 2 weft yarn 2G knit portion 2S bobbin portion 3 weft reversal point 4 rotor 4a-4c yarn guide 5 rotor 5a-5c yarn guide 6 knock-over bit 7 latch needle 7a latch 8 guide needle 9 bobbin 10 side wall 11 foundation 12 pair of rollers 13 take-up roll 20, 21 rotors 20a, 20b, 21a, 21b yarn guide 30, 31 rotors 30a, 30b, 31a, 31b yarn guide 40, 41 rotors 40a, 40b, 41a, 41b yarn guide B stroke range RZ direction R1 direction of rotation R2 direction of rotation HI direction HR direction P take-off direction KG warp-knit fabric BG full machine width BT stroke range of one pair