FABRIC TAPE

Abstract

A forming fabric tape for a machine for producing and/or processing a fiber material web, the forming fabric tape including an upper fabric layer including upper longitudinal threads and upper transversal threads woven into the upper longitudinal threads; and a lower fabric layer including lower longitudinal threads and lower transversal threads woven into the lower longitudinal threads, wherein the upper fabric layer and the lower fabric layer are arranged on top of one another so that the upper fabric layer is oriented towards the fiber material web being produced when the fabric tape is being used in the machine and the lower fabric layer is oriented away from the fiber material web being produced, wherein a first distance A1 between two directly adjacent lower longitudinal threads is greater and a second distance A2 between two directly adjacent lower longitudinal threads.

Claims

1. A forming fabric tape for a machine for producing or processing a fiber material web, the forming fabric tape comprising: an upper fabric layer including upper longitudinal threads and upper transversal threads woven into the upper longitudinal threads; and a lower fabric layer including lower longitudinal threads and lower transversal threads woven into the lower longitudinal threads, wherein the upper fabric layer and the lower fabric layer are arranged on top of one another so that the upper fabric layer is oriented towards the fiber material web and the lower fabric layer is oriented away from the fiber material web, wherein a first distance A1 between two directly adjacent lower longitudinal threads is greater and a second distance A2 between two directly adjacent lower longitudinal threads, and wherein a difference between the first distance A1 and the second distance A2 is between 20% and 175% of a diameter of the upper longitudinal threads.

2. The forming fabric tape according to claim 1, wherein a weaving pattern of the fabric tape is repeated in pattern repeats, wherein the upper longitudinal threads and the lower longitudinal threads are arranged in each pattern repeat in plural groups, including a first group I, a second group II and at least one additional first or second group I, II, wherein each first group I is respectively formed from an upper longitudinal thread and a lower longitudinal thread arranged below the upper longitudinal thread and each second group II is respectively formed either from two upper longitudinal threads and a lower longitudinal thread arranged below the two upper longitudinal threads or an upper longitudinal thread and two lower longitudinal threads arranged below the upper longitudinal thread.

3. The forming fabric tape according to claim 2, wherein all second groups II are respectively formed from two upper longitudinal threads and a lower longitudinal thread arranged below the two upper longitudinal threads, and wherein two lower longitudinal threads of two directly adjacent second groups II have the first distance A1 from each other and two lower longitudinal threads of a first group I and a second group II directly adjacent to the first group I have the second distance A2 from each other.

4. The forming fabric tape according to claim 2, wherein all second groups II are respectively formed from two upper longitudinal threads and a lower longitudinal thread arranged below the two upper longitudinal threads, wherein two lower longitudinal threads of two directly adjacent first groups I have the second distance A2 from each other, and wherein two lower longitudinal threads of a first group I and a second group II directly adjacent to the first group I have the first distance A1 from each other.

5. The forming fabric tape according to claim 3, wherein a minimum distance a3 of the upper longitudinal threads is provided between the two upper longitudinal threads of a second group II.

6. The forming fabric tape according to claim 3, wherein a minimum distance a3 between two directly adjacent upper longitudinal threads is at least 50% of a diameter of an upper longitudinal thread or corresponds to a sum of the diameter of the upper longitudinal thread and the diameter of the lower longitudinal thread at the most.

7. The forming fabric tape according to claim 2, wherein all second groups II are respectively formed from an upper longitudinal thread and two lower longitudinal threads arranged below the upper longitudinal thread, wherein the two lower longitudinal threads of a second group II have the second distance A2 from each other, and wherein the two lower longitudinal threads of a first group I and a second group II directly adjacent to the first group I have the first distance A1 from each other.

8. The forming fabric tape according to claim 7, wherein the upper longitudinal threads are arranged so that their average distances have the subsequent sequence repeated in the transversal direction of the fabric tape: large distance a1, large distance a1, small distance a2, wherein a difference between an average large distance a1 and an average small distance a2 is at least 60% or at least 120% of a diameter of an upper longitudinal thread.

9. The forming fabric tape according to claim 1, wherein a difference between a maximum distance a1 of two directly adjacent upper longitudinal threads and a minimum distance a1, a2 of two directly adjacent longitudinal threads is 200% at the most or 150% at the most of a diameter of an upper longitudinal thread O1-O5.

10. The forming fabric tape according to claim 2, wherein the upper fabric layer and the lower fabric layer are connected with each other by binding threads arranged in pairs.

11. The forming fabric tape according to claim 10, wherein the binding threads run in the transversal direction of the fabric tape.

12. The forming fabric tape according to claim 10, wherein two binding threads of respective binding thread pair are woven with the upper longitudinal threads and the lower longitudinal threads in an alternating pattern and intersect when woven in the alternating pattern with the upper longitudinal threads and the lower longitudinal threads and vice versa forming intersection points.

13. The forming fabric tape according to claim 12, wherein each binding thread pair includes at least two intersection points in the pattern repeat.

14. The forming fabric tape according to claim 10, wherein the upper fabric layer is formed by weaving the upper longitudinal threads with the upper transversal threads and the binding threads and the lower fabric layer is formed by weaving the lower longitudinal threads with the lower transversal threads.

15. The forming fabric tape according to claim 1, wherein the upper fabric layer is provided in plain weave.

16. The forming fabric tape according to claim 2, wherein all second groups II are respectively formed from an upper longitudinal thread and two lower longitudinal threads arranged below the upper longitudinal thread, wherein the two lower longitudinal threads of a second group II have the second distance A2 from each other, and wherein the two lower longitudinal threads of two directly adjacent first groups I have the first distance A1 from each other.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The invention is subsequently described based on advantageous embodiments with reference to drawing figures, wherein:

[0026] FIG. 1 illustrates a schematic view of a first embodiment of a fabric tape according to the invention;

[0027] FIG. 2 illustrates a schematic view of a second embodiment of a fabric tape according to the invention; and

[0028] FIG. 3 illustrates a schematic view of a third embodiment of a fabric tape according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0029] FIG. 1 schematically illustrates a first embodiment of a fabric tape according to the invention. FIG. 1 only shows the upper longitudinal threads O1-O5 and the lower longitudinal threads U1-U3 which form a repeat unit WE in combination, but does not show other longitudinal threads which are woven together with the upper longitudinal threads O1-O5 to form an upper fabric layer and lower transversal threads which are woven together with the lower longitudinal threads U1-U3 to form a lower fabric layer and binding threads which connect the upper fabric layer with the lower fabric layer. The binding threads are advantageously configured as an integral part of the weaving pattern, in particular of a plain weave of the upper fabric layer, whereas they do no contribute to the weaving pattern of the lower fabric layer.

[0030] The fabric tape is assembled by a concatenation of pattern repeats in the longitudinal direction and the transversal direction. With respect to the upper longitudinal threads O1-O5 and the lower longitudinal threads U1-U3 a pattern repeat can include or consist of a single repeat unit WE. Typically, a repeat pattern includes plural repeat units WE. It is appreciated that a pattern repeat is not only defined by the longitudinal threads but also by the transversal threads and the binding threads. When the upper fabric layer is advantageously provided in plain weave a pattern repeat has to include an even number of upper longitudinal threads. Since the repeat unit WE can include or consist of five upper longitudinal threads O1-O5 in the first embodiment according to FIG. 1 the pattern repeat has to include an integer multiple of the repeat units WE, thus at least two repeat units WE.

[0031] In the instant first embodiment, a repeat unit WE is formed from three groups of longitudinal threads, namely a second group II including two upper longitudinal threads O1 and O2 and a lower longitudinal thread U1, an additional second group II, including two upper longitudinal threads O3 and O4 and a lower longitudinal thread U2 and a first group I only including an upper longitudinal thread O5 and a lower longitudinal thread U3. Between the first lower longitudinal thread U1 and the second lower longitudinal thread U2 a relatively large distance A1 is provided, whereas a second relatively small distance A2 is provided between the second lower longitudinal thread U2 and the third lower longitudinal thread U3. The same second relatively small distance A2 is arranged between the third lower longitudinal thread U3 and a first lower longitudinal thread U1 of a directly adjacent repeat unit. Thus, a continuously repeating sequence is provided in this embodiment, with respect to the spacing of the lower longitudinal threads in the transversal direction of the fabric tape, wherein the sequence includes the first distance, the second distance and again the second distance.

[0032] In this embodiment according to FIG. 1, also the upper longitudinal threads O1-O5 of the repeat unit WE are unevenly spaced from each other. The two upper longitudinal threads O1-O2 and O3-O4 that are respectively associated with a second group II have a relatively small distance a3 from each other. The distance a1 between the lower longitudinal thread O5 that is part of the first group I from a directly adjacent upper longitudinal thread O4 or O1 of a second group II is greater. The distance a2 between the two directly adjacent upper longitudinal threads O2 and O3 of the two second groups II is smaller than the distance a1 but greater than the distance a3.

[0033] In this embodiment, all upper longitudinal threads O1-O5 have the same circular cross section and all lower longitudinal threads U1-U3 have the same circular cross section, which however is greater than the circular cross section of the upper longitudinal threads.

[0034] The dimensions in this embodiment can be selected as follows: [0035] Diameter of upper longitudinal threads O1-O5: 0.10 mm [0036] Diameter of the lower longitudinal threads U1-U3: 0.21 mm [0037] First distance A1: 0.28 mm [0038] Second distance A2: 0.20 mm [0039] Distance a1: 0.20 mm [0040] Distance a2: 0.15 mm [0041] Distance a3: 0.13 mm

[0042] This yields an extension of the repeat unit WE of 1.31 mm. The difference between the first distance A1 and the second distance A2 is 0.08 mm which corresponds to 80% of the diameter of the upper longitudinal threads.

[0043] It is appreciated that the distances, in particular the distances a1-a3, between the upper longitudinal threads O1-O5 does not have to be constant over an entire longitudinal extension of the fabric tape. These distances can also become narrower and then wider again. Thus, the average distance is relevant as described supra.

[0044] FIG. 2 schematically illustrates a second embodiment of a fabric tape according to the invention, only showing the upper longitudinal threads O1-O4 and the lower longitudinal threads U1-U3 forming a repeat unit in combination but not showing the upper transversal threads, which are woven together with the upper longitudinal threads O1-O4 to form the upper fabric layer, lower transversal threads which are woven together with the lower longitudinal threads U1-U3 to form a lower fabric layer and binding threads which connect the upper fabric layer with the lower fabric layer. Thus, the binding threads are an integral part of the weaving pattern, in particular of a plain weave of the upper fabric layer, whereas they do not contribute to the weaving pattern of the lower fabric layer.

[0045] The instant second embodiment includes a repeat unit WE including three groups of longitudinal threads, namely a second group II including two upper longitudinal threads O1 and O2 and a lower longitudinal thread U1, a first group I including an upper longitudinal thread O3 and a lower longitudinal thread U2, and an additional first group I, including an upper longitudinal thread O4 and a lower longitudinal thread U3. A first relatively large distance A1 is arranged between the first lower longitudinal thread U1 and the second lower longitudinal thread U2, whereas a relatively small distance A2 is arranged between the second lower longitudinal thread U2 and the third lower longitudinal thread U3. The first relatively large distance A1 is also arranged between the third lower longitudinal thread U3 and a first lower longitudinal thread U1 of a directly adjacent repeat unit. This embodiment shows a continuously repeating sequence of first distance, second distance, first distance repeated in the transversal direction of the fabric tape with respect to the spacing of the lower longitudinal threads.

[0046] In this embodiment according to FIG. 2 the upper longitudinal threads O1-O4 of the repeat unit WE are spaced unevenly from each other. The two upper longitudinal threads O1-O2 that are part of the second group II have a relatively small distance a3 from each other. The distance a1 between the upper longitudinal thread O3 that is part of the first group and the upper longitudinal thread O4 that is part of the additional first group I is greater. The distance a2 between the upper longitudinal thread O2 of the second group II and a directly adjacent longitudinal thread O3 of the first group I is between the distance a1 and the distance a3.

[0047] In this embodiment, all upper longitudinal threads O1-O4 have the same circular cross section and all lower longitudinal threads U1-U3 have the same circular cross section, which however is greater.

[0048] The dimensions in this embodiment can be selected as follows: [0049] Diameter of upper longitudinal threads O1-O4: 0.10 mm [0050] Diameter of the lower longitudinal threads U1-U3: 0.21 mm [0051] First distance A1: 0.22 mm [0052] Second distance A2: 0.17 mm [0053] Distance a1: 0.27 mm [0054] Distance a2: 0.22 mm [0055] Distance a3: 0.13 mm

[0056] This yields a total extension of the repeat unit WE of the 1.24 mm. The difference between the first distance A1 and the second distance A2 is 0.05 mm which corresponds to 50% of the diameter of the upper longitudinal threads.

[0057] It is appreciated that the distances, in particular the distances a1-a3, between the upper longitudinal threads O1-O4 do not have to be constant over the entire longitudinal extension of the fabric tape. The distances can also become narrower and wider again. Therefore the average distance is being considered also in this case.

[0058] FIG. 3 schematically illustrates a third embodiment of a fabric tape according to the invention, showing only the upper longitudinal threads O1-O3 and the lower longitudinal thread U1-U4 which form a repeat unit WE in combination but not showing upper transversal threads which are woven together with the upper longitudinal threads O1-O3 forming an upper fabric layer, lower transversal threads which are woven together with the lower longitudinal threads U1-U4 forming a lower fabric layer and binding threads which connect the upper fabric layer with the lower fabric layer. Thus, the binding threads advantageously are an integral part of the weaving pattern, in particular of a plain weave of the upper fabric layer, whereas they do not contribute to the weaving pattern of the lower fabric layer.

[0059] The instant third embodiment shows a repeat unit WE including three groups of longitudinal threads, namely a first group I including an upper longitudinal thread O1 and a lower longitudinal thread U1, a second group II including an upper longitudinal thread O2 and two lower longitudinal threads U2 and U3 and an additional second group I including an upper longitudinal thread O3 and a lower longitudinal thread U4. A first relatively large distance A1, is provided between the first lower longitudinal thread U1 and the second lower longitudinal thread U2 and between the third lower longitudinal thread U3 and the fourth lower longitudinal thread U4, whereas a second relatively small distance A2 is provided between the second lower longitudinal thread U2 and the third lower longitudinal thread U3. The first relatively large distance A1 is also arranged between the fourth lower longitudinal thread U4 and a first lower longitudinal thread U1 of a directly adjacent repeat unit. This yields a continuously repeating sequence of first distance, second distance, first distance and first distance in the transversal direction of the fabric tape, in this embodiment with respect to the spacing of the lower longitudinal threads.

[0060] In this embodiment according to FIG. 3 also the upper longitudinal threads O1-O3 of the repeat unit WE are unevenly spaced from each other. The upper longitudinal thread O3 has a relatively small distance a2 from the directly adjacent upper longitudinal threads O1 of an adjacent repeat unit. The distance a1 between the upper longitudinal thread O1 that is part of the first group I and the upper longitudinal thread O2 that is part of the second group II is greater. The same distance a1 is also provided between the upper longitudinal thread O2 that is part of the second group II, and the upper longitudinal thread O3, that is part of the additional first group I. This yields the following continuously repeating sequence of the upper longitudinal threads in the transversal direction: large distance, large distance, small distance.

[0061] In this embodiment all upper longitudinal threads O1-O3 have the same circular cross section and all lower longitudinal threads U1-U4 have the same circular cross section which, however, is greater.

[0062] The dimensions in this embodiment can be selected as follows: [0063] Diameter of upper longitudinal threads O1-O4: 0.14 mm [0064] Diameter of the lower longitudinal threads U1-U3: 0.19 mm [0065] First distance A1: 0.095 mm [0066] First distance A2: 0.049 mm [0067] Distance a1: 0.2645 mm [0068] Distance a2: 0.145 mm

[0069] This yields a total extension of the repeat unit WE of the 1.094 mm. The difference between the first distance A1 and the second distance A2 is 0.046 mm which corresponds to 33% of the diameter of the upper longitudinal threads.

[0070] It is appreciated that the distances, in particular the distances a1 and a2 between the upper longitudinal threads O1-O3 do not have to the constant over the entire longitudinal extension of the fabric tape. They can also become narrower and wider again. Therefore, the average distance is relevant also in this instance.