Forming fabric

Abstract

A woven-fabric web, such as a forming fabric or forming wire, for a machine for producing and/or processing a fibrous web, has a first woven-fabric layer with first longitudinal threads and first transverse threads interwoven with the first longitudinal threads and a second woven-fabric layer with second longitudinal threads and second transverse threads interwoven with the second longitudinal threads. The weaving pattern of the fabric is repeated in pattern repeats. The first and second longitudinal threads are arranged in a plurality of groups in each pattern repeat, with a first group and a second group and at least one further of the first and/or second group. Each first group is formed from a first longitudinal thread and a second longitudinal thread arranged below the first longitudinal thread and the first and second longitudinal threads in each group are arranged at no offset or only a slight offset in plan view.

Claims

1. A fabric tape for a machine for manufacturing and/or processing a fibrous web, the fabric tape comprising: a first fabric layer having first longitudinal threads and first cross threads interwoven with said first longitudinal threads; a second fabric layer having second longitudinal threads and second cross threads interwoven with said second longitudinal threads; said first and second fabric layers being disposed on top of one another and having a weaving pattern repeated in repeats; said first longitudinal threads and said second longitudinal threads in each repeat being disposed in a plurality of groups, having one first group and one second group and at least one further of said first and/or second group; each said first group being formed by one first longitudinal thread and one second longitudinal thread disposed below said one first longitudinal thread; each said second group being formed by two first longitudinal threads and one second longitudinal thread disposed below said two first longitudinal threads; said first and second longitudinal threads in each group, viewed in a projection perpendicularly onto said fabric layers, being disposed so as not to be offset or only slightly offset in relation to one another, with a maximum offset defining a free space of half a diameter of a first longitudinal thread therebetween; and wherein a number of first groups of longitudinal threads is different from a number of second groups of longitudinal threads.

2. The fabric tape according to claim 1, wherein: said first and second groups in the repeat are disposed in a plurality of superordinate groups of longitudinal threads; each superordinate group of longitudinal threads comprises a first group, a second group, and at least one further group being a first or second group; the repeat is formed by an integral number of superordinate groups of longitudinal threads disposed next to one another in a cross-thread direction.

3. The fabric tape according to claim 1, wherein the same of the first or second group of longitudinal threads is disposed directly next to one another at maximum four times.

4. The fabric tape according to claim 1, configured as a forming wire for processing fibrous material, with said first fabric layer having an outer side facing away from said second fabric layer and which, on use of the forming wire, provides a paper side to be brought into contact with the fibrous material.

5. The fabric tape according to claim 1, configured as a forming wire, with said second fabric layer having an outer side facing away from said first fabric layer and which, on use of the fabric tape, provides a machine side to be brought into contact with the machine.

6. The fabric tape according to claim 1, wherein the fabric tape has only said first and second groups of longitudinal threads.

7. The fabric tape according to claim 1, which comprises binder threads disposed in pairs and connecting said first and second fabric layers to one another.

8. The fabric tape according to claim 7, wherein said binder threads extend in a cross-thread direction.

9. The fabric tape according to claim 7, wherein each pair of binder threads has two binder threads respectively interwoven in a mutually interchanging manner with first and second longitudinal threads and intersecting at intersection points upon changing from being interwoven with the first longitudinal threads to being interwoven with the second longitudinal threads and vice-versa.

10. The fabric tape according to claim 9, wherein each respective pair of binder threads in the repeat provides for two intersection points.

11. The fabric tape according to claim 7, wherein said binder threads of each pair of binder threads, between immediately successive intersection points, form in each case first binder segments by interweaving with said first longitudinal threads, and at least one of said first binder segments of each pair of binder threads is formed in the repeat in that the respective said binder thread, running on an outer side of said first fabric layer, intersects at least four, not immediately successive first longitudinal threads.

12. The fabric tape according to claim 11, wherein said binder threads of each pair of binder threads in the repeat together form two first binder segments, wherein the one first binder segment is formed in that the one binder thread of the pair, when being interwoven with the first longitudinal threads, runs alternatingly on the outer side of the first fabric layer and between the first and second fabric layers and, running on the outer side of the first fabric layer, intersects at least two first longitudinal threads, and wherein the other first binder segment is formed in that the other binder thread of the pair, when being interwoven with the first longitudinal threads, runs alternatingly on the outer side of the first fabric layer and between the first and second fabric layers and, running on the outer side of the first fabric layer, intersects the same number of first longitudinal threads as the one binder thread.

13. The fabric tape according to claim 11, wherein said binder threads of each pair of binder threads in the repeat together form two first binder segments, wherein the one first binder segment is formed in that the one binder thread of the pair, when being interwoven with the first longitudinal threads, runs alternatingly on the outer side of the first fabric layer and between the first and second fabric layers and, running on the outer side of the first fabric layer, intersects at least two first longitudinal threads, and wherein the other first binder segment is formed in that the other binder thread of the pair, when being interwoven with the first longitudinal threads, runs alternatingly on the outer side of the first fabric layer and between the first and second fabric layers and, running on the outer side of the first fabric layer, intersects a number of first longitudinal threads that is greater or smaller by up to four first longitudinal threads than the one binder thread.

14. The fabric tape according to claim 13, wherein the other binder thread intersects up to two fewer or more first longitudinal threads than the one binder thread.

15. The fabric tape according to claim 7, wherein said first fabric layer is formed by interweaving said first longitudinal threads with said first cross threads and said binder threads, and said second fabric layer is formed by interweaving said second longitudinal threads with said second cross threads.

16. The fabric tape according to claim 1, wherein a ratio of first warp threads to second warp threads is greater than 1.5.

17. The fabric tape according to claim 16, wherein the ratio of the first warp threads to the second warp threads is smaller than 2.

18. The fabric tape according to claim 1, wherein said first fabric layer forms a plain weave.

19. The fabric tape according to claim 1, wherein said first and second fabric layers are configured as a forming wire for a papermaking machine.

20. A fabric tape for a machine for manufacturing and/or processing a fibrous web, the fabric tape comprising: a first fabric layer having first longitudinal threads and first cross threads interwoven with said first longitudinal threads; a second fabric layer having second longitudinal threads and second cross threads interwoven with said second longitudinal threads; said first and second fabric layers being disposed on top of one another and having a weaving pattern repeated in repeats; binder threads disposed in pairs and connecting said first and second fabric layers to one another; said first longitudinal threads and said second longitudinal threads in each repeat being disposed in a plurality of groups, having one first group and one second group and at least one further of said first and/or second group; each said first group being formed by one first longitudinal thread and one second longitudinal thread disposed below said one first longitudinal thread; each said second group being formed by two first longitudinal threads and one second longitudinal thread disposed below said two first longitudinal threads; said first and second longitudinal threads in each group, viewed in a projection perpendicularly onto said fabric layers, being disposed so as not to be offset or only slightly offset in relation to one another, with a maximum offset defining a free space of no more than one half a diameter of a first longitudinal thread; said binder threads of each pair of binder threads, between immediately successive intersection points, forming in each case first binder segments by interweaving with said first longitudinal threads, and at least one of said first binder segments of each pair of binder threads being formed in the repeat in that the respective said binder thread, running on an outer side of said first fabric layer, intersects at least four, not immediately successive first longitudinal threads.

Description

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

(1) FIGS. 1A, 1B, 1C, 1D, and 1E are highly diagrammatic view of various designs of the construction and the arrangement of the two layers of longitudinal threads, according to the invention;

(2) FIG. 2 shows a repeat of a further embodiment of a fabric tape according to the invention, in the direction of the cross threads;

(3) FIG. 3 shows the arrangement of the two layers of longitudinal threads of the fabric tape shown in FIG. 2;

(4) FIG. 4 shows the arrangement of a second group of longitudinal threads; and

(5) FIG. 5 shows the arrangement of a first group of longitudinal threads.

DETAILED DESCRIPTION OF THE INVENTION

(6) Referring now to the figures of the drawing in detail and first, particularly, to FIGS. 1A to 1E thereof, there are shown a plurality of designs of the construction and the arrangement of longitudinal threads 3, 4 in a first and second fabric layer 1, 2 of a fabric tape according to the invention. The illustration of FIGS. 1A-1E shows the relative arrangement of the longitudinal threads 3, 4 of a first and second fabric layer 1, 2, in a sectional plane which is perpendicular to the first and second longitudinal threads 3, 4. For the sake of clarity, an illustration of the cross threads and (any potential) binder threads of the fabric tape according to the invention has been dispensed with in FIGS. 1A-1E. It should furthermore be noted that the arrangements of first and second groups, shown in FIGS. 1A-1E, may be repeated several times in the repeat of a fabric tape according to the invention, that is to say that the arrangement shown in the respective figure in each case represents one superordinate group of longitudinal threads which is repeated several times in the repeat, wherein the repeat is formed only by an integral number of the shown superordinate groups of longitudinal threads which are disposed next to one another in the cross-thread direction.

(7) As can be identified in FIG. 1A, the two fabric layers 1, 2 are disposed on top of one another, and the first longitudinal threads 3 and the second longitudinal threads 4 are disposed in a plurality of groups 5, 6. In the present case, four first groups 5 and one second group 6 are formed here, that is to say that one superordinate group of longitudinal threads is formed by four first groups 5 and one second group 6. The first groups 5 are all disposed in an immediately adjoining manner to one another, followed by the one second group 6. Each of the first groups 5, in the present case, is constructed from one first longitudinal thread 3 and, disposed therebelow, one second longitudinal thread 4, wherein, in the present case, the first and second longitudinal threads 3, 4, when viewed in a projection which is perpendicular onto the fabric layers, are disposed so as not to be offset in relation to one another. The second group 6 is furthermore constructed from two first longitudinal threads 3 and, disposed therebelow, one second longitudinal thread 4, wherein, in the present case, the two first longitudinal threads, when viewed in a projection which is perpendicular onto the fabric layers 1, 2, are disposed so as to be only slightly offset in relation to one another, such that said two first longitudinal threads mutually overlap. In the present case, the ratio of first longitudinal threads to second longitudinal threads is 6:5=1.2.

(8) The embodiment illustrated in FIG. 1B differs from the embodiment shown in FIG. 1A merely in that the fabric tape comprises only three first groups instead of four first groups, that is to say that one superordinate group of longitudinal threads is formed by three first groups 5 and one second group 6. Therefore, the ratio of first longitudinal threads to second longitudinal threads is 5:4=1.25. Except for this, all other implementations realized in FIG. 1A also apply to the embodiment of FIG. 1B.

(9) The embodiment illustrated in FIG. 1C differs from the embodiment shown in FIG. 1A only in that the fabric tape comprises only two first groups instead of four first groups, that is to say one superordinate group of longitudinal threads is formed by two first groups 5 and one second group 6. Therefore, the ratio of first longitudinal threads to second longitudinal threads is 4:3=1.333. Except for this, all other implementations realized in FIG. 1A also apply to the embodiment of FIG. 1C.

(10) As can be identified in FIG. 1D, the two fabric layers 1, 2 are disposed on top of one another, and the first longitudinal threads 3 and the second longitudinal threads 4 are disposed in a plurality of groups 5, 6. In the present case, seven first groups 5 and three second groups 6 are formed here, that is to say that one superordinate group of longitudinal threads is formed by seven first groups 5 and three second groups 6. The arrangement of the first and second groups 5, 6 in relation to one another here is such that an arrangement which is formed from three immediately adjoining first groups 5 is provided, followed by one united second group 6, and in turn followed by an arrangement from three immediately adjoining first groups 5, and on which, following therefrom, in turn one second group 6, one first group 5 and again one second group 6 are disposed in an alternating manner. In the present case, each of the first groups 5 is constructed from one first longitudinal thread 3 and, disposed therebelow, one second longitudinal thread 4, wherein, in the present case, the first and second longitudinal threads 3, 4, when viewed in a projection which is perpendicular onto the fabric layers, are disposed so as not to be offset in relation to one another. The second group 6 is furthermore constructed from two first longitudinal threads 3 and, disposed therebelow, one second longitudinal thread 4, wherein, in the present case, the two first longitudinal threads, when viewed in a projection which is perpendicular onto the fabric layers 1, 2, are disposed so as to be only slightly offset in relation to one another, such that said two first longitudinal threads mutually overlap. In the present case, the ratio of first longitudinal threads to second longitudinal threads is 13:10=1.3.

(11) As can be identified in FIG. 1E, the two fabric layers 1, 2 are disposed on top of one another, and the first longitudinal threads 3 and the second longitudinal threads 4 are disposed in a plurality of groups 5, 6. In the present case, three first groups 5 and two second groups 6 are formed here, that is to say that one superordinate group of longitudinal threads is formed by three first groups 5 and two second groups 6. Immediately successive first groups 5 are in each case separated from one another by one second group 6. In the present case, each of the first groups 5 is constructed from one first longitudinal thread 3 and, disposed therebelow, one second longitudinal thread 4, wherein, in the present case, the first and second longitudinal threads 3, 4, when viewed in a projection which is perpendicular onto the fabric layers, are disposed so as not to be offset in relation to one another. The second group 6 is furthermore constructed from two first longitudinal threads 3 and, disposed therebelow, one second longitudinal thread 4, wherein, in the present case, the two first longitudinal threads, when viewed in a projection which is perpendicular onto the fabric layers 1, 2, are disposed so as to be only slightly offset in relation to one another, such that said two first longitudinal threads mutually overlap. In the present case, the ratio of first longitudinal threads to second longitudinal threads is 7:5=1.4.

(12) FIG. 2 shows a repeat of a further embodiment of a fabric tape 100 according to the invention, in the direction of the cross threads.

(13) It should be pointed out that the illustration of FIG. 2 is a merely schematic one and in particular depicts the arrangement of the first and second longitudinal threads in relation to one another, according to the invention, only in an incomplete manner. The correct arrangement of the first and second longitudinal threads is depicted in FIG. 3, however, without the cross threads and binder threads being shown there.

(14) The fabric tape 100 has a first fabric layer 101 and a second fabric layer 102. The outer side of the first fabric layer 101, which faces away from the second fabric layer 102, here provides a paper side, and the outer side of the second fabric layer 102, which faces away from the first fabric layer 101, provides a machine side.

(15) The first fabric layer 101 is formed by interweaving first longitudinal threads 1, 3, 4, 6, 8, 11, 12, 14, 16, 17, 19, 20, 22, 24, 25, 27, 28, 30, and 32 with the first cross threads T1-T12 and with the binder threads Bi1-Bi12, which are disposed in pairs, wherein the weaving pattern of the first fabric layer is a plain weave.

(16) The second fabric layer 102 is formed by interweaving second longitudinal threads 2, 5, 7, 10, 13, 15, 18, 21, 23, 26, 29, and 31 with second cross threads B1-B12, wherein the weaving pattern of the second fabric layer is a satin weave which is repeated in second repeats which are formed from six second longitudinal threads and six second cross threads.

(17) The ratio of the first longitudinal threads to the second longitudinal threads in the present case is 5:3. Furthermore, the ratio of first cross threads and pairs of binder threadshere, each pair of binder threads counts as one first cross threadto the second cross threads is 3:2.

(18) As can be obtained from the illustration of FIG. 2, two first cross threads T1-T12 and two second cross threads B1-B12 are in each case disposed between two immediately successive pairs of binder threads Bi1/Bi2; Bi3/Bi4; Bi5/Bi6; Bi7/Bi8; Bi9/Bi10; Bi11/B12.

(19) The binder threads which are disposed in pairs of each pair are interwoven in a mutually interchanging manner with the first and the second longitudinal threads and here intersect when changing from being interwoven with first longitudinal threads to being interwoven with second longitudinal threads and vice-versa, while configuring intersection points K1, K2. In the present case, each pair of binder threads Bi1/Bi2; Bi3/Bi4; Bi5/Bi6; Bi7/Bi8; Bi9/Bi10; Bi11/Bi12 in the repeat provides two intersection points K1, K2, wherein the binder threads, when changing from being interwoven with the first longitudinal threads to being interwoven with the second longitudinal threads and vice-versa, running between the two fabric layers 101, 102 intersect at maximum three immediately adjoining second longitudinal threads.

(20) Furthermore, in the present case the binder threads of each pair of binder threads in the repeat together form in each case two first binder segments BS1, BS2, wherein the one first binder segment BS1 is formed in that the one binder thread of the pair, when being interwoven with the first longitudinal threads, runs in an alternating manner on the outer side of the first fabric layer 101 and between the first and second fabric layers 101, 102 and, running on the outer side of the first fabric layer 101, intersects at least five first longitudinal threads, and wherein the other first binder segment BS2 is formed in that the other binder thread of the pair, when being interwoven with the first longitudinal threads, runs in an alternating manner on the outer side of the first fabric layer and between the first and second fabric layers and, running on the outer side of the first fabric layer, intersects the same number of first longitudinal threads as the one binder thread.

(21) FIG. 3 shows the relative arrangement of the first and second longitudinal threads of the fabric tape to one another, illustrated in FIG. 2, using the example of the first longitudinal threads 1, 3, 4, 6 and 8 and the second longitudinal threads 2, 5, and 7. The arrangement shown here of first groups I and second groups II represents a superordinate group OG of longitudinal threads which is repeated four times in the repeat, such that the repeat of the fabric tape has the following arrangement of first and second groups: second group-first group-second group-second group-first group-second group-second group-first group-second group-second group-first group-second group.

(22) In other words, the repeat is formed by four superordinate groups OG of longitudinal threads which are disposed next to one another in the cross-thread direction.

(23) This means that in the present exemplary embodiment the longitudinal threads of the fabric tape 100 form only first and second groups, wherein, in the present case, eight second groups II and four first groups I are present in the repeat.

(24) One identifies that the first longitudinal threads 1, 3 form a second group II with the second longitudinal thread 2. One furthermore identifies that the first longitudinal threads 6, 8 form a further second group II with the second longitudinal thread 7. One first group, which is formed by the first longitudinal thread 4 and the second longitudinal thread 5, is disposed between the two aforementioned second groups. What has been stated above correspondingly applies to first and second groups I, II, which are formed by the further first and second longitudinal threads.