Knitted fabric, method for producing a knitted fabric, and warp knitting machine

Abstract

A knitted fabric, a method of producing the knitted fabric and a warp knitting machine. The knitted fabric includes a first covering layer; a second covering layer; and an arrangement of pile threads formed as spacer threads between the first covering layer and the second covering layer. Each covering layer includes multiple stitch rows arranged one after another. The spacer threads have different lengths, and the spacer threads woven into each stitch row have equal lengths. The spacer threads in a first width region have a different length than the spacer threads in a second width region. For at least two adjacent stitch rows, one stitch row is connected to spacer threads of a first length in the first width region and one stitch row is connected to spacer threads of a second length in the second width region.

Claims

1. A knitted fabric comprising: a first covering layer; a second covering layer; and an arrangement of pile threads formed as spacer threads between the first covering layer and the second covering layer, wherein each covering layer comprises multiple stitch rows arranged one after another, wherein the spacer threads in a first width region have a different length than the spacer threads in a second width region, and wherein, for at least two adjacent stitch rows, a first stitch row is connected to spacer threads of a first length in the first width region and a second stitch row is connected to spacer threads of a second length in the second width region, whereby the spacer threads knitted into each stitch row have equal lengths.

2. The knitted fabric according to claim 1, wherein stitch rows having spacer threads of the first length and stitch rows having spacer threads of the second length alternate with one another.

3. The knitted fabric according to claim 1, further comprising a transition region arranged between the first width region and the second width region, which is free of spacer threads.

4. The knitted fabric according to claim 1, further comprising a transition region arranged between the first width region and the second width region, in which spacer threads having a length of a greater of the different lengths are arranged.

5. The knitted fabric according to claim 1, wherein the pile threads are respectively knitted into one of the covering layers in regions in which the pile threads do not connect the two covering layers.

6. The knitted fabric according to claim 1, wherein, at least in one predetermined length section of the knitted fabric, each stitch row comprises a width section that is free of spacer threads.

7. A method for producing a knitted fabric comprising: producing a first covering layer with a series of first stitch rows arranged one after another in a direction of production and a second covering layer with a series of second stitch rows arranged one after another in the direction of production; and knitting pile threads arranged between the two covering layers into the covering layers as spacer threads, wherein a distance between the covering layers is not constant and regions having different length spacer threads are produced, wherein the spacer threads are knitted into a first width region at a first distance between the covering layers and the spacer threads are knitted into a second width region at a second distance between the covering layers.

8. The method according to claim 7, wherein the spacer threads are only knitted into a first width region at a first distance between the covering layers and the spacer threads are only knitted into a second width region at a second distance between the covering layers.

9. The method according to claim 7, wherein alternation occurs between the first distance and the second distance.

10. The method according to claim 9, wherein, at least on one predetermined length section of the knitted fabric, a different distance between the covering layers is set for each new stitch row.

11. The method according to claim 10, wherein, at least in the predetermined length section, one width section is formed without spacer threads in each stitch row.

12. The method according to one of claim 8, wherein pile threads which are not used as spacer threads in a width section are carried along in a covering layer.

13. A warp knitting machine comprising: two knitting regions structured and arranged for producing respective one covering layers; an actuating drive structured and arranged to adjust a distance between the knitting regions to produce at least first and second width regions between the covering layers having different thicknesses corresponding to the adjusted distance; at least one pile guide bar having guide needles, the at least one pile guide bar being movable with the guide needles back and forth between the knitting regions; and a control device structured and arranged to adjust the guide needles depending on the distance between the knitting regions to knit first spacer threads in the first width region and second spacer threads in the second width region so that a length of the first spacer threads is different from a length of the second spacer threads, wherein, for at least two adjacent stitch rows, one stitch row is connected to the first spacer threads of the first length in the first width region and one stitch row is connected to the second spacer threads of the second length in the second width region, and wherein the at least one pile guide bar is formed as a jacquard guide bar, the guide needles of which are adjustable between a working position and a resting position.

14. The warp knitting machine according to claim 13, wherein the control device is further structured to control the actuating drive.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The present invention is further described in the detailed description which follows, in reference to the noted plurality of drawings by way of non-limiting examples of exemplary embodiments of the present invention, in which like reference numerals represent similar parts throughout the several views of the drawings, and wherein:

(2) FIG. 1 shows a perspective representation of knitted fabric;

(3) FIG. 2 shows a sectional view of the knitted fabric;

(4) FIG. 3 shows a schematic representation of the arrangement of spacer threads; and

(5) FIG. 4: shows a highly schematized representation for the purpose of illustrating a warp knitting machine.

DETAILED DESCRIPTION OF THE PRESENT INVENTION

(6) The particulars shown herein are by way of example and for purposes of illustrative discussion of the embodiments of the present invention only and are presented in the cause of providing what is believed to be the most useful and readily understood description of the principles and conceptual aspects of the present invention. In this regard, no attempt is made to show structural details of the present invention in more detail than is necessary for the fundamental understanding of the present invention, the description taken with the drawings making apparent to those skilled in the art how the several forms of the present invention may be embodied in practice.

(7) A knitted fabric 1 illustrated in FIG. 1 comprises a first covering layer 2 and a second covering layer 3. Spacer threads 4, 5 are arranged between two covering layers 2, 3. Spacer threads 4, 5 are pile threads which connect the two covering layers 2, 3 to one another. The spacer threads 4, 5 are thus woven into the two covering layers 2, 3. For the purpose of illustration, a direction of production 6 is also represented by an arrow. A width direction 7 illustrated by a double arrow runs transversely to direction of production 6. It can be seen that knitted fabric 1 comprises in width direction 7 a first width region 8 having a lesser thickness and a second region 9 having a greater thickness. In the exemplary embodiment illustrated here, first width region 8 has a thickness of 3 mm and second width region 9 has a thickness of 5 mm.

(8) FIG. 2 shows a sectional representation through knitted fabric 1. Identical elements are provided with the same reference numerals.

(9) Embodiments of the invention produce knitted fabric of this type with the smallest possible effort.

(10) A warp knitting machine 10 used for this purpose is illustrated in FIG. 4 in a highly schematized form. Warp knitting machine 10 comprises a first weaving area 11 which comprises two ground guide bars GB1, GB2. Furthermore, in a manner not illustrated in greater detail, additional elements can be provided, in particular, a knitting needle bar and a comb plate.

(11) Furthermore, warp knitting machine 10 comprises a second knitting region 12, of which two ground guide bars GB3, GB4 are illustrated here.

(12) Knitting region 11 produces covering layer 2. Knitting region 12 produces covering layer 3.

(13) Furthermore, an actuating drive 13 is provided with which the distance between the two knitting regions 11, 12 can also be adjusted during operation of warp knitting machine 10. The distance between the two knitting regions 11, 12 at a particular point in time typically defines the thickness of knitted fabric 1 that has been produced at said point in time.

(14) Pile guide bar PJB5 serves to guide pile threads 14 back and forth between the two covering layers 2, 3 as spacer threads 4, 5 and to also weave them into covering layers 2, 3 when this is necessary. This is explained below.

(15) Of course, multiple pile threads 14 of this type are provided perpendicularly to the drawing plane.

(16) Pile guide bar PJB5 can be moved in the displacement direction, that is, parallel to its longitudinal extension. It comprises guide needles 15 that can be individually controlled by a piezo drive 16, for example, counter to the displacement movement of pile guide bar PJB5. If piezo drive 16 is actuated during a displacement movement of pile guide bar PJB5, then guide needle 15 remains stationary as it were. If piezo drive 16 is not actuated, then guide needle 15 is also moved in the displacement direction and can therefore participate in a stitch-formation process. Only by a stitch-formation process is it possible to weave pile thread 14 into covering layer 2 or into covering layer 3.

(17) Piezo drive 16 is controlled by a control device 17. Control device 17 also controls actuating drive 13, which determines the distance between the two knitting regions 11, 12.

(18) Control device 17 thus knows which distance is present between the two knitting regions 11, 12 during a stitch-formation operation. Accordingly, control device 17 also knows which distance is present between the two covering layers 2, 3 at a particular moment in which pile threads 14 are to be laid as spacer threads.

(19) In order to achieve the different distances between covering layers 2, 3 in width direction 7, an approach is used such as is described on the basis of FIG. 3. FIG. 3 shows a series of stitch rows a, b, c, d, e, f. The series of stitch rows a-f forms, for example, covering layer 2. All stitches of a stitch row of covering layer 2 or of the covering layer 3 are produced simultaneously.

(20) In stitch rows a-f, positions are represented by a small circle. In these positions, pile threads 14 are woven into both covering layers 2, 3. Furthermore, positions are represented by dots in stitch rows a-f. Here, pile threads 14 are not woven into respective covering layers 2, 3.

(21) On the basis of FIG. 3, it can be seen that in width region 8, pile threads 14 are only woven into covering layers 2, 3 as spacer threads 4 at every second stitch row b, d, f. In contrast, no spacer threads 4 are provided in the other stitch rows a, c, e. At the moments in which the stitch rows b, d, f are produced, the two knitting regions 11, 12 have the lesser distance of 3 mm, for example. Accordingly, spacer threads 4 also have a length of 3 mm.

(22) In width region 9, the respectively other stitch rows a, c, e are provided with spacer threads 5 which have been woven into the two covering layers 2, 3. However, stitch rows b, d, f do not have any spacer threads. At the moments in which stitch rows a, c, e are produced, the two knitting regions 11, 12 have a greater distance between them of 5 mm, for example. Accordingly, spacer threads 5 then also have a length of 5 mm.

(23) Control device 17 controls both actuating drive 13, with which the distance between the two knitting regions 11, 12 can be adjusted, and also piezo drive 16 of pile guide bar PJB5. Accordingly, it is possible in a simple manner to only weave spacer threads 4 into stitch rows b, d, f of covering layers 2, 3 when the two knitting areas 11, 12 have the lesser distance to one another and to only weave spacer threads 5 into the respectively other stitch rows a, c, e when the two covering layers 2, 3 have the respectively greater distance to one another.

(24) Of course, it is also possible to achieve more than the two width regions 8, 9 illustrated and more than two different thicknesses.

(25) An additional change in thickness in direction of production 6 is also possible.

(26) Pile threads 14 which are not used in stitch rows a, c, e in width region 8 can be woven into one of the two covering layers 2, 3 or they can be arranged between the two covering layers 2, 3 in a floating or loose manner. Pile threads 14 that are not woven into covering layers 2, 3 in stitch rows b, d, fin width region 9 can also be arranged between the two covering layers 2, 3 in a loose or floating manner.

(27) In particular, knitted fabric 1 can be used where shoe materials are used.

(28) In FIG. 3, it is shown that the individual stitch rows a-f are alternatingly filled with varyingly long spacer threads 4, 5. Although this is advantageous, it is not mandatory. It is also possible to provide two or three stitch rows respectively with shorter pile threads and then in turn provide two or three stitch rows with longer pile threads.

(29) A transition region 18 is provided between the two width regions 8, 9. This transition region 18 can be kept free of spacer threads. However, it is also possible to dispose the longer of the transition threads here. These transition threads are then slightly compressed, which is not problematic, however.

(30) It is noted that the foregoing examples have been provided merely for the purpose of explanation and are in no way to be construed as limiting of the present invention. While the present invention has been described with reference to an exemplary embodiment, it is understood that the words which have been used herein are words of description and illustration, rather than words of limitation. Changes may be made, within the purview of the appended claims, as presently stated and as amended, without departing from the scope and spirit of the present invention in its aspects. Although the present invention has been described herein with reference to particular means, materials and embodiments, the present invention is not intended to be limited to the particulars disclosed herein; rather, the present invention extends to all functionally equivalent structures, methods and uses, such as are within the scope of the appended claims.