PRESS BELT

The invention is an endless belt for a machine for the production of a fibrous material web, the belt being formed by a flat woven structure and a connecting region. The flat woven structure has longitudinal threads extending in the MD direction and transverse threads extending in the CMD direction. Every longitudinal thread, has a first thread end section, which protrudes beyond the first end of the woven structure, and a second thread end section, which protrudes beyond the second end of the woven structure. The two ends of the flat woven structure are connected to each other by the connecting region, which is formed by weaving the first and second end sections of the longitudinal threads to the second transverse threads, thereby forming a plurality of pairs of a first and a second thread end section, wherein the two thread end sections are disposed directly adjacent to each other and the two thread end sections form a common overlapping region in that the first and second end sections of the pair are woven with the at least consecutive second transverse threads, and the two end sections of the pair follow the same weaving path in the overlapping region.

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Description
CROSS REFERENCE TO RELATED APPLICATIONS

This is a continuation of PCT application No. PCT/EP2008/051821, entitled “PRESS BELT”, filed Feb. 15, 2008, which is incorporated herein by reference.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to an endless belt for a machine for the production of a fibrous material web, the belt being designed for an application where a tensile stress of at least 30 kN/m acts on the belt in the longitudinal extent of the belt. The invention further relates to a pressing apparatus for a machine for the production of a fibrous material web, in which such an endless belt is used as a press belt.

2. Description of the Related Art

In the recent past, a new pressing apparatus has been proposed in which an extended press nip is formed, in that a press belt that is under tension is led over an opposing surface. In this case, the opposing surface is generally formed by a section of the circumferential surface of a roll. The new pressing apparatus is distinguished, in particular, by the fact that the fibrous material web is dewatered in the direction of the opposing surface by the pressing force of the belt and the action of at least one fluid flowing in the direction from the press belt toward the opposing surface. By way of the extended press nip, higher dryness values of the paper made in this way are achieved, in particular for tissue paper.

The press belts used are in particular permeable woven structures, which are woven flat and then subsequently made endless on the machine by way of a pintle seam connection. Since these press belts are subjected to tensile stresses of at least 30 kN/m but often between 40 and 70 kN/m, this type of seam proves to be a weak point, in particular with respect to its durability.

What is needed in the art is a belt that can perform under a tensile stress of at least 30 kN/m, with an improved connection.

SUMMARY OF THE INVENTION

The present invention is an endless belt for a machine for the production of a fibrous material web, the belt being designed for an application where a tensile stress of at least 30 kN/m acts thereon. The belt according to the present invention includes a fabric having a flat woven structure and having a connecting region. The flat woven structure has longitudinal threads extending in the machine direction (MD) and first transverse threads woven therewith and extending in the cross machine direction (CMD). The flat woven structure is delimited in its longitudinal extent by a first end on the longitudinal side and a second end on the longitudinal side. Each longitudinal thread, viewed in its longitudinal extent, has a first thread end section, which protrudes beyond the first end of the woven structure on the longitudinal side in the MD, and a second thread end section, which protrudes beyond the second end of the woven structure on the longitudinal side in the MD direction. In order to make the belt endless, the two ends on the longitudinal sides of the flat woven structure are connected to each other by the connecting region. The connection is formed by weaving the first and second end sections of the longitudinal threads with second transverse threads, thereby forming a large number of pairs of a first and a second thread end section in each case. The two thread end sections, viewed in the CMD, are arranged directly beside each other. The two thread end sections, viewed in the MD, form a common overlapping region, in that the first end section of the pair is woven with at least 15 consecutive second transverse threads, with which also the second end section of the pair is woven. The two end sections of the pair follow the same weaving path in the overlapping region.

The belt according to the present invention includes a fabric. By a technique of interwoven longitudinal and transverse threads, a structure is provided which is capable of absorbing high tensile stresses. The connecting region in the belt, according to the present invention, is designed in such a way that the thread end sections of the longitudinal threads extend into the connecting region in the MD direction and here are woven with further transverse threads in order to form the connecting region. The longitudinal thread sections, which point toward each other as the belt is made endless, form pairs of first and second longitudinal thread end sections which, viewed in the CMD, are arranged directly beside one another and which, as viewed in the MD direction, overlap in a common section of at least 15 consecutive transverse threads and thereby weave the same weaving path.

As a result of the large overlapping region, which the two longitudinal thread end sections that are directly adjacent to each other in the CMD have with each other in the MD, a secure connection is provided. Since the two longitudinal thread end sections of a pair weave the same weaving path with the consecutive transverse threads in the common overlapping region, there is the possibility of continuing the weaving pattern of the flat woven structure in the connecting region, which makes it possible to create a connecting region which has the same properties (such as permeability, open and closed structure) as the flat woven structure.

The belt according to the present invention is generally produced with the flat woven structure being produced first and it is then joined together by the woven connecting region to form an endless belt. The endless belt is then drawn into the machine.

Advantageously, as viewed in the MD, each overlapping region is terminated by the first and the second thread end section being led to an outer side of the fabric.

Trials carried out by the applicant have shown that, depending on the tensile stress occurring in the specific application, it may be expedient if the overlapping regions include up to 60 consecutive second transverse threads. For the application specified in the present case in a belt press under tensile stresses of 30 kN/m and more, trials have shown that it is sufficient if the overlapping regions have 18 to 25 consecutive second transverse threads.

Preferably, each overlapping region includes the same number of second transverse threads.

Preferably, the first and the second transverse threads are identical with respect to their shape and nature and the material from which these are made.

In order to improve the durability of the seam further, at least some sections, in the connecting region is additionally reinforced with polymer material or adhesive. The polymer material or adhesive is preferably applied to the connecting region in the liquid state and produces an adhesive connection between the first and second thread end sections in their respective overlapping region. In this case, the polymer material or the adhesive can be applied in such a way that the permeability in this region is no lower than in regions without any adhesive applied as a liquid or a polymer material applied as a liquid. This can be done, for example, with the adhesive or the polymer material, which is deposited in the meshes of the fabric, having some of it blown away by compressed air.

Additionally or alternatively, the two thread end sections of a pair can be welded to each other, at least in some sections, in the overlapping region. This can be brought about, for example, way of ultrasonic welding.

In order to be able to make the entire connecting region longer in the MD without enlarging the individual overlapping regions thereby, a preferred embodiment of the present invention provides for the overlapping regions arranged beside one another in the CMD to be offset in relation to one another, as viewed in the MD direction. By way of the lengthened connecting region, improved durability of the connection is achieved. Furthermore, the lengthened connecting region achieves the situation where the overlapping regions are not all arranged along a single line extending in the CMD, by which a potential tendency of marking by the belt at this point is prevented.

The relative offset in the MD of overlapping regions arranged directly beside one another in the CMD preferably includes 20 to 60, more preferably 30 to 40, consecutive second transverse threads.

In order to be able to make the endless belt according to the present invention simply, provision is made for a large number of consecutive overlapping regions each to have the same offset in relation to one another.

A further embodiment of the present invention provides for the flat woven structure and the connecting region to have the same weaving pattern. In this case, the weaving pattern of the flat woven structure is continued by the weaving pattern of the connecting region without an offset between the two weaving patterns arising. This makes it possible to provide an endless belt which has the same properties over its entire length and over the connecting region. In this way, an endless belt is created in which the connecting region has the same properties as the flat woven structure.

The fabric of the belt according to the present invention can be constructed both with one layer, that is to say with one longitudinal thread layer and one transverse thread layer, or with two or more layers, that is to say with two or more longitudinal thread layers and/or transverse thread layers.

As is the case in all fabrics, the weaving pattern of the press belt is repeated in repeat units. For the application of the belt according to the invention as a press belt, a large number of types of weave are suitable. For example, a repeat unit can form either a plain weave or a 5-shaft satin weave.

Furthermore, the arrangement of the overlapping regions is repeated in repeats; in this case it is expedient if the repeat of the arrangement of the overlapping regions includes more longitudinal threads and/or more transverse threads than the repeat of the flat woven structure.

In order to improve the connection of the end sections of the flat woven structure further, a development of the invention provides for the longitudinal extent of the connecting region, defined by the two overlapping regions which are furthest apart from each other, as viewed in the MD, to be between 5 cm and 100 cm, preferably between 10 cm and 70 cm, particularly preferably between 40 cm and 60 cm. This means that, according to this refinement, the entire connecting region can extend in the MD direction over a length in the range from 5 to 100 cm, preferably between 10 cm and 70 cm, particularly preferably between 40 cm and 60 cm.

One embodiment of the present invention provides for the endless belt to be formed only by the fabric.

If the belt according to the present invention is used as a press belt in a belt press apparatus, then dewatering of the fibrous material web takes place in that the fibrous material web is dewatered simultaneously in the direction of the opposing surface by the pressing force of the belt and the action of at least one fluid flowing in the direction from the press belt toward the opposing surface. For the practical application of the belt according to the present invention as a press belt, it is expedient if the belt is permeable and preferably has a permeability between 100 cfm and 1200 cfm, and more preferably between 300 cfm and 800 cfm.

The belt is preferably designed for an application in which a tensile stress between 40 and 70 kN/m acts on the belt.

Furthermore, provision can be made for the longitudinal threads to be warp threads and for the transverse threads to be weft threads.

Furthermore, the present invention relates to an improved pressing apparatus for a machine for the production of a fibrous material web, in which use is made of an endless belt as described above as a press belt. The press belt being under a tensile stress of at least 30 kN/m and, in order to provide an extended press nip, being led over an opposing surface which is preferably formed by a section of the circumferential surface of a roll, in particular a suction roll. The fibrous material web is led between the belt and the opposing surface and the belt exerts a pressing force on the fibrous material web on account of its tensile stress.

The tissue web is preferably led through the pressing apparatus according to the present invention in a sandwich made of an upper permeable fabric and a lower permeable fabric, so that the result is the following structure:

1) press belt

2) upper permeable fabric

3) tissue web

4) lower permeable fabric

5) opposing surface.

In this case, the upper permeable fabric is preferably a three-dimensionally structured fabric, such as a through air drying (TAD) fabric. Furthermore, the lower permeable fabric is preferably a press felt.

A pressing apparatus which is equipped with a belt according to the present invention operates considerably more reliably, on account of the more stable design of the connecting region, than a pressing device which is equipped with a conventional press belt but which is otherwise identical.

In order to be able to achieve both good dewatering of the tissue web by the mechanical tension of the belt according to the present invention and also on account of a fluid flow through the belt, it is expedient for the belt to have an open area of at least 25% and to have a contact area of at least 10% of its total area pointing toward the upper fabric.

BRIEF DESCRIPTION OF THE DRAWINGS

The above-mentioned and other features and advantages of this invention, and the manner of attaining them, will become more apparent and the invention will be better understood by reference to the following description of embodiments of the invention taken in conjunction with the accompanying drawings, wherein:

FIG. 1 shows a pressing apparatus which is equipped with a belt according to an embodiment of the present invention as a press belt;

FIG. 2 shows the course of the warp threads of a belt according to the present invention in the connecting region and in the region of the flat woven structure;

FIGS. 3a and 3b show the relative arrangement of the overlapping regions in relation to one another in another view of the belt from FIG. 2;

FIG. 4 shows, in a plan view of a section, the connecting region and the flat woven structure of the belt shown in FIGS. 2 and 3; and

FIG. 5 shows, in a plan view of a section, the connecting region and the flat woven structure of another embodiment of the belt according to the present invention.

Corresponding reference characters indicate corresponding parts throughout the several views. The exemplification set out herein illustrates embodiments of the invention, in one form, and such exemplifications are not to be construed as limiting the scope of the invention in any manner.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to the drawings and more particularly to FIG. 1 there is shown a machine 1 for the production of a fibrous material web 2, which is equipped with a pressing apparatus 3 having a belt 4 according to the present invention as a press belt 4.

Fibrous material web 2, which is a tissue web 2 in the present case, is formed in a forming section 5 of machine 1 by a liquid fibrous material suspension being introduced into an inlet gap 6 between a conventional permeable and flat forming fabric 7 and a permeable and three-dimensionally structured fabric 8. Structured fabric 8 has a surface which touches fibrous material web 2 and which, as compared with the surface of flat fabric 7 that touches fibrous material web 2, has larger elevations and depressions.

After fibrous material web 2 has run around a forming roll 9 in the sandwich between forming fabric 7 and structured fabric 8 for the purpose of dewatering, forming fabric 7 is lifted off of fibrous material web 2. Fibrous material web 2 is then fed to pressing apparatus 3 on structured fabric 8.

In pressing apparatus 3, endless belt 4 according to the present invention is used as a press belt 4. The press belt 4 is under a tensile stress of at least 30 kN/m in pressing apparatus 3. In order to provide an extended press nip, press belt 4 is led over an opposing surface which, in the present case, is formed by a section of the circumferential surface of a suction roll 10 in the region of a suction zone Z. In order to dewater tissue web 2 in pressing apparatus 3, tissue web 2 is led in the sandwich between the permeable three-dimensionally structured fabric 8 and a permeable smooth belt 11 designed as a press felt 11. In this case, press belt 4 makes contact with structured fabric 8 and press felt 11 is supported on the circumferential surface of suction roll 10. In this case, because of its tensile stress, press belt 4 exerts a pressing force on the sandwich which includes structured fabric 8, fibrous material web 2 and press felt 11.

Arranged above press belt 4 there is also a blowing apparatus 16 which has the effect that a fluid flow of hot air and/or steam flows through press belt 4, structured fabric 8, fibrous material web 2 and press felt 11 to suction zone Z. Consequently, in pressing apparatus 3, fibrous material web 2 is dewatered by the simultaneous action of the pressing force of belt 4 on fibrous material web 2 and the fluid flowing through the fibrous material web 2 in the direction from press belt 4 toward the opposing surface, of suction roll 10.

After passing through pressing apparatus 3, press felt 11 is lifted off fibrous material web 2 and the latter is fed on structured fabric 8 to a press nip 14 formed between a press roll 12 and a Yankee drying cylinder 13 for further dewatering.

After passing through press nip 14, fibrous material web 2 is lifted off structured fabric 8 and led on the circumferential surface of Yankee drying cylinder 13 in order subsequently to be lifted off Yankee drying cylinder 13 by way of a doctor device 15.

Now additionally referring to FIG. 2 there is shown the courses of the warp threads of a repeat unit of belt 4 according to the present invention, which is used in machine 1 of FIG. 1. Belt 4 has the warp thread course illustrated both in the region of the flat woven structure and in the connecting region. The weaving pattern of the fabric continuing from the flat woven structure into the connecting region without any interruption or offset.

In the present case, a 5-shaft satin weave having longitudinal threads K1-K5 as warp threads is shown. In the repeat, each warp thread K1-K5, runs on the underside (US) of the fabric crossing four weft threads and, runs on the top side (OS) of the fabric crossing one weft thread. For example, warp thread K1 runs on the underside US crossing the four consecutive weft threads S1-S4 before, running on the top side OS and crossing weft thread S5.

In the present case, the weft threads are designated only in accordance with their position and not depending on whether they are first or second weft threads (a number before the designation indicates whether this is a first or second weft thread; the number after the designation indicates the position of the weft thread).

Table 1 shows the technical data of the belt according to the invention of FIG. 2.

TABLE 1 Diarn Material % % by Yarn details No/cm (mm) Type Cover Weight Warp: 12 0 0 45 PET 54.00 39 Weft: 12 9 0 50 PET 64.50 61 Fabric Details Warp Weft Aperture size (mm × mm): 0.38 0.27 Open Area %: 16.3 Air permeability (cfm): 750 Fibre Support Index: 38 Drainage Index: 10 Warp Breaking Strength N/cm: 1247 Warp % Extension at Break: 17.8 Thickess (mm): 1.24 Basis Weight (g/m2): 693

Now, additionally referring to FIGS. 3a and 3b, there is shown a course of one of warp threads K1-K5 of belt 4 according to the present invention from FIG. 2 in a section of the flat woven structure and in a section of the connecting region.

In the illustration of FIG. 3a, a section of the weaving path of one of warp threads K1-K5 can be seen as the thread weaves over a plurality of repeats in the manner described in FIG. 2. Since all of the warp threads K1-K5 have the same weaving paths, which differ only by a relative offset in the MD in relation to one another, corresponding to the 5-shaft satin weave shown in FIG. 2, the following text can be applied as an example to all the weaving paths of warp threads K1-K5 of a warp repeat of the fabric. The exemplary warp thread is provided with the designation Kx, where x can be=1, 2, 3, 4, 5.

The pairs of parallel lines in FIG. 3a indicate an interruption to the representation of the weaving path of the warp thread Kx, which in reality continues.

Endless belt 4 is designed for an application in which a tensile stress of at least 30 kN/m acts on the belt. Endless belt 4 is formed only by a single-layer fabric 20. Fabric 20 is formed by a flat woven structure 21 and a connecting region 22.

Flat woven structure 21 is formed by the weaving of warp threads K1-K5 extending in the MD and first transverse threads 1S are woven therewith and extend in the CMD, the first transverse threads 1S being weft threads.

The flat woven structure 21 is delimited in its longitudinal extent by a first end on the longitudinal side and a second end on the longitudinal side. The two ends of the flat woven structure on the longitudinal side are not shown in the illustration of FIG. 3a for reasons of space but, for this purpose, are shown in the illustration of FIG. 4.

According to the present invention, each longitudinal thread Kx, viewed in its longitudinal extent, has a first thread end section which protrudes beyond the first end of the woven structure on the longitudinal side in the MD, and a second thread end section which protrudes beyond the second end of the woven structure on the longitudinal side in the MD. In the illustration of FIG. 3a, the first thread end section of one of the warp threads K1 to K5 is provided with the designation Kx.1 and the second thread end section of the same warp thread Kx is provided with the designation Kx.2.

According to the present invention, the two ends of the flat woven structure on the longitudinal side are connected to each other in connecting region 22 in order to make the belt endless. The first and the second end sections of longitudinal threads K1 to K5 are woven with second transverse threads 2S, formed as weft threads, such that the weaving pattern of the flat woven structure 21 is continued by the weaving pattern of connecting region 22 without any interruption. Consequently, the flat woven structure 21 and connecting region 22 have the same weaving pattern.

In the illustration of the weaving path of warp thread Kx, it can be seen that the first thread end section Kx.1 of warp thread Kx is woven with second transverse threads 2S, and second thread end section Kx.2 of the same warp thread Kx is woven with second transverse threads 2S.

During the weaving of the thread end sections of warp threads K1-K5, the thread end sections form a large number of pairs each including a first and a second thread end section, in which the two thread end sections, viewed in the CMD, are arranged directly beside each other, and in which the two thread end sections, viewed in the MD, form a common overlapping region. The first end section of the pair is woven with the same at least 15 consecutive second transverse threads 2S, with which also the second end section of the pair is woven, and the two end sections of the pair follow the same weaving path in the overlapping region.

In belt 4 according to the present invention from FIG. 3a, the first and the second thread end section Kx.1 and Kx.2 of the same longitudinal thread Kx always form a pair in which the two thread end sections Kx.1 and Kx.2, as viewed in the CMD, are arranged directly beside each other. That is to say no thread end section of another warp thread is arranged between the thread end sections forming the pair. Furthermore, in the MD, the two thread end sections Kx.1 and Kx.2 of the same warp thread Kx form an overlapping region Üy, in that the first end section of the pair Kx.1 is woven with the same 18 consecutive second transverse threads 2S, with which also the second end section Kx.2 of the pair is woven, and in that the two end sections Kx.1 and Kx.2 of the pair follow the same weaving path in the overlapping region Üy.

From the illustration of FIG. 3a, it is also possible to see that each overlapping region Üy, viewed in the MD, is terminated in that the first thread end section Kx.1 and the second thread end section Kx.2 are led to an outer side of fabric 20. The two ends of the overlapping region Üy are designated 1Ey and 2Ey in FIG. 3a.

Since the course of warp thread Kx illustrated in FIG. 3a is representative of all the warp thread courses K1-K5, each overlapping region Ü15 in belt 4 illustrated has the same number of second transverse threads.

FIG. 3b shows the five overlapping regions Ü1 to Ü5 following one another in the CMD. The offset of mutually adjacent overlapping regions in the present case is respectively 40 second transverse threads 2S, the offset always being determined by the shortest distance of one end of an overlapping region from the end of the following overlapping region which is located closest to the first-named end. For instance, the offset between the two consecutive overlapping regions Ü1 and Ü2 is determined by the distance between the end 2E1 of the overlapping region Ü1 and the end 1E2 of the overlapping region Ü2. Furthermore, for instance, the offset between the two consecutive overlapping regions Ü2 and Ü3 is defined by the distance between the end 2E2 of the overlapping region Ü2 and the end 1E3 of the overlapping region Ü3. The principle is continued in the further overlapping regions.

Now, additionally referring to FIG. 4 there is shown, in a plan view of a section, connecting region 22 and flat woven structure 21 of belt 4 according to the present invention from FIGS. 2 and 3.

The illustration of FIG. 4 shows the relative arrangement of the overlapping regions in relation to one another, in particular in connecting region 22. Furthermore, FIG. 4 shows an extract from flat woven structure 21 and the two ends 23 and 24 delimiting the flat woven structure, which are connected to each other in endless belt 4 by connecting region 22. FIG. 4 shows belt 4 only in a partial length and only in a partial width.

The illustrated extract from connecting region 22 shows three repeats R1, R2 and R3 arranged beside one another in the CMD from the arrangement of overlapping regions. As viewed in the MD, connecting region 22 extends over the length of a repeat. Each repeat R1, R2 and R3 of overlapping regions is formed by the overlapping regions Ü1 to Ü35. Therefore, repeat R1, R2 and R3 of the arrangement of overlapping regions is greater than the repeat which forms the weaving pattern formed by warp threads K1-K5 and weft threads S1-S5 of flat woven structure 21 and of connecting region 22. Overlapping regions Ü1 to Ü35 which, viewed in the CMD, are arranged directly beside one another, are offset in relation to one another, as viewed in the MD. Thus, for example, the two consecutive overlapping regions Ü1 and Ü2 are offset in relation to one other by 40 second transverse threads 2S, the offset always being determined by the shortest distance of one end of an overlapping region to the end of the following overlapping region which is located closest to the first-named end.

In the present case, at least some overlapping regions of a repeat which follow one another directly, as viewed in the CMD have the same offset in relation to one another. For instance, all of the overlapping regions Ü1 to Ü9 following one another in each case have the same offset in relation to one another.

All of the overlapping regions lie on a family of straight lines parallel to one another, consecutive overlapping regions arranged on a straight line in each case always having the same offset in relation to one another and all the straight lines of the family being spaced apart equally from one another.

The longitudinal extent of connecting region 22, defined by the two overlapping regions Ü34 and Ü35 which, as viewed in the MD, are spaced furthest apart from each other, is 60 cm.

The belt is permeable and in the present case has a permeability of 750 cfm.

Now, additionally referring to FIG. 5 there is shown a further embodiment of a belt 4 according to the present invention. In the present case, the same features are provided with the same designations as in the preceding Figs. Belt 4, viewed in the MD, has in connecting region 22 a section A in which all the overlapping regions Üa to Üe extend.

While this invention has been described with respect to at least one embodiment, the present invention can be further modified within the spirit and scope of this disclosure. This application is therefore intended to cover any variations, uses, or adaptations of the invention using its general principles. Further, this application is intended to cover such departures from the present disclosure as come within known or customary practice in the art to which this invention pertains and which fall within the limits of the appended claims.

Claims

1. An endless belt for a machine for the production of a fibrous material web, the belt having a tensile stress of at least 30 kN/m acting on the belt, the belt comprising:

a fabric formed by a flat woven structure and a connecting region, the flat woven structure including: a plurality of longitudinal threads extending in the machine direction (MD); a plurality of first transverse threads woven with at least a portion of said plurality of longitudinal threads, said first transverse threads extending in a cross machine direction (CMD); and a plurality of second transverse threads, said flat woven structure being delimited in its longitudinal extent by a first end on a longitudinal side of said flat woven structure and a second end on the longitudinal side, each of said longitudinal threads as viewed in its longitudinal extent having: a first thread end section protruding beyond said first end of said woven structure on the longitudinal side in the MD; and a second thread end section protruding beyond said second end of said woven structure on the longitudinal side in the MD, said first end and said second end being connected to each other in said connecting region which is formed by weaving said first thread end section and second thread end section of the longitudinal threads with said second transverse threads to thereby form a plurality of pairs of first and second thread end sections, in which the two thread end sections as viewed in the CMD are arranged directly beside each other, and in which the two thread end sections as viewed in the MD form a common overlapping region in which the first thread end section and the second thread end section of the pair are woven with at least 15 consecutive second transverse threads with each thread of the pair following the same weaving path in the overlapping region.

2. The endless belt of claim 1, wherein in each overlapping region as viewed in the MD direction the first and the second thread end section are terminated by being led to an outer side of the fabric.

3. The endless belt of claim 1, wherein the overlapping regions include up to 60 consecutive said second transverse threads.

4. The endless belt of claim 3, wherein the overlapping regions have from 18 to 25 consecutive said second transverse threads.

5. The endless belt of claim 1, wherein each overlapping region has the same number of second transverse threads.

6. The endless belt of claim 1, wherein the first and the second thread end section of the same longitudinal thread always form a pair.

7. The endless belt of claim 1, wherein said connecting region has a section in which all of said overlapping regions extend in the MD.

8. The endless belt of claim 1, wherein the overlapping regions following one another in the CMD as viewed in the MD are offset in relation to one another.

9. The endless belt of claim 8,wherein the offset of at least some consecutive overlapping regions is from 20 to 60 consecutive second transverse threads.

10. The endless belt of claim 9, wherein the offset of at least some consecutive overlapping regions is from 30 to 40 consecutive second transverse threads.

11. The endless belt of claim 8, wherein a substantial number of consecutive overlapping regions each have the same offset in relation to one another.

12. The endless belt of claim 1, wherein the flat woven structure and the connecting region have the same weaving pattern.

13. The endless belt of claim 1, wherein the fabric has one of one layer and more than one layer.

14. The endless belt of claim 1, wherein the weaving pattern of the flat woven structure is repeated in repeats, said repeat being one of a plain weave and a 5-shaft satin weave.

15. The endless belt of claim 14, wherein the arrangement of the overlapping regions is repeated in repeats, said repeat of the arrangement of the overlapping regions including at least one of more longitudinal threads and more transverse threads than a repeat of the flat woven structure.

16. The endless belt of claim 1, wherein the longitudinal extent of the connecting region as defined by the two overlapping regions which are furthest apart from each other as viewed in the MD is one of between 5 cm and 100 cm, between 10 cm and 70 cm and between 40 cm and 60 cm.

17. The endless belt of claim 1, wherein the belt is formed only by the fabric.

18. The endless belt of claim 1, wherein the belt is permeable having a permeability between approximately 100 cfm and 1200 cfm.

19. The endless belt of claim 18, wherein said permeability is between 300 cfm and 800 cfm.

20. The endless belt of claim 1, wherein the belt is configured for use in an application in which a tensile stress of between 40 and 70 kN/m acts on the belt.

21. The endless belt of claim 1, wherein the longitudinal threads are warp threads and the transverse threads are weft threads.

22. A pressing apparatus for a machine for the production of a fibrous material web, comprising:

an endless belt configured to operate under a tensile stress of at least 30 kN/m;
a roll having a circumferential surface defining an opposing surface, said endless belt extending over a section of said circumferential surface thereby providing an extended press nip, said roll being a suction roll, the fibrous material web being led between the belt and said opposing surface, the belt exerting a pressing force on the fibrous material web on account of its tensile stress, said endless belt being a fabric formed by a flat woven structure and a connecting region, the flat woven structure including: a plurality of longitudinal threads extending in the machine direction (MD); a plurality of first transverse threads woven with at least a portion of said plurality of longitudinal threads, said first transverse threads extending in a cross machine direction (CMD); and a plurality of second transverse threads, said flat woven structure being delimited in its longitudinal extent by a first end on a longitudinal side of said flat woven structure and a second end on the longitudinal side, each of said longitudinal threads as viewed in its longitudinal extent having: a first thread end section protruding beyond said first end of said woven structure on the longitudinal side in the MD; and a second thread end section protruding beyond said second end of said woven structure on the longitudinal side in the MD, said first end and said second end being connected to each other in said connecting region which is formed by weaving said first thread end section and second thread end section of the longitudinal threads with said second transverse threads to thereby form a plurality of pairs of first and second thread end sections, in which the two thread end sections as viewed in the CMD are arranged directly beside each other, and in which the two thread end sections as viewed in the MD form a common overlapping region in which the first thread end section and the second thread end section of the pair are woven with at least 15 consecutive second transverse threads with each thread of the pair following the same weaving path in the overlapping region.

23. The pressing apparatus of claim 22, wherein the pressing apparatus is configured to process the fibrous material web therethrough sandwiched between a permeable three-dimensionally structured fabric and a permeable smooth belt, said permeable smooth belt being a press felt, said press belt making contact with said structured fabric and said smooth belt making contact with said opposing surface.

24. The pressing apparatus of claim 23, wherein the fibrous material web is dewatered in a direction of said opposing surface by way of the pressing force of the belt and by action of at least one fluid flowing in a direction from said press belt toward said opposing surface.

Patent History
Publication number: 20100032120
Type: Application
Filed: Aug 20, 2009
Publication Date: Feb 11, 2010
Inventors: Martin Ringer (Lancashire), Lippi A. Fernandes (Brummen), Andrew Cartwright (Lancs)
Application Number: 12/544,757
Classifications
Current U.S. Class: With Felt Structure Or Felt Composition (162/358.2)
International Classification: D21J 3/00 (20060101);