U.S. patent application number 12/544757 was filed with the patent office on 2010-02-11 for press belt.
Invention is credited to Andrew Cartwright, Lippi A. Fernandes, Martin Ringer.
Application Number | 20100032120 12/544757 |
Document ID | / |
Family ID | 39415119 |
Filed Date | 2010-02-11 |
United States Patent
Application |
20100032120 |
Kind Code |
A1 |
Ringer; Martin ; et
al. |
February 11, 2010 |
PRESS BELT
Abstract
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.
Inventors: |
Ringer; Martin; (Lancashire,
GB) ; Fernandes; Lippi A.; (Brummen, NL) ;
Cartwright; Andrew; (Lancs, GB) |
Correspondence
Address: |
TAYLOR & AUST, P.C.
P.O. Box 560, 142. S Main Street
Avilla
IN
46710
US
|
Family ID: |
39415119 |
Appl. No.: |
12/544757 |
Filed: |
August 20, 2009 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
PCT/EP2008/051821 |
Feb 15, 2008 |
|
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12544757 |
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Current U.S.
Class: |
162/358.2 |
Current CPC
Class: |
D21F 1/0054 20130101;
D21F 3/0272 20130101; D21F 3/0209 20130101 |
Class at
Publication: |
162/358.2 |
International
Class: |
D21J 3/00 20060101
D21J003/00 |
Foreign Application Data
Date |
Code |
Application Number |
Feb 21, 2007 |
DE |
DE102007008500.3 |
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.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] 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
[0002] 1. Field of the Invention
[0003] 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.
[0004] 2. Description of the Related Art
[0005] 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.
[0006] 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.
[0007] 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
[0008] 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.
[0009] 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.
[0010] 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.
[0011] 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.
[0012] 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.
[0013] 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.
[0014] Preferably, each overlapping region includes the same number
of second transverse threads.
[0015] 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.
[0016] 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.
[0017] 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.
[0018] 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.
[0019] 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.
[0020] 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.
[0021] 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.
[0022] 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.
[0023] 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.
[0024] 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.
[0025] 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.
[0026] One embodiment of the present invention provides for the
endless belt to be formed only by the fabric.
[0027] 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.
[0028] The belt is preferably designed for an application in which
a tensile stress between 40 and 70 kN/m acts on the belt.
[0029] Furthermore, provision can be made for the longitudinal
threads to be warp threads and for the transverse threads to be
weft threads.
[0030] 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.
[0031] 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:
[0032] 1) press belt
[0033] 2) upper permeable fabric
[0034] 3) tissue web
[0035] 4) lower permeable fabric
[0036] 5) opposing surface.
[0037] 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.
[0038] 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.
[0039] 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
[0040] 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:
[0041] FIG. 1 shows a pressing apparatus which is equipped with a
belt according to an embodiment of the present invention as a press
belt;
[0042] 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;
[0043] 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;
[0044] 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
[0045] 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.
[0046] 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
[0047] 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.
[0048] 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.
[0049] 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.
[0050] 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.
[0051] 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.
[0052] 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.
[0053] 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.
[0054] 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.
[0055] 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.
[0056] 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).
[0057] Table 1 shows the technical data of the belt according to
the invention of FIG. 2.
TABLE-US-00001 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 .times.
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/m.sup.2): 693
[0058] 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.
[0059] 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.
[0060] 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.
[0061] 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.
[0062] 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.
[0063] 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.
[0064] 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.
[0065] 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.
[0066] 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.
[0067] 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.
[0068] 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 Uy, 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 Uy.
[0069] From the illustration of FIG. 3a, it is also possible to see
that each overlapping region Uy, 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 Uy are designated 1Ey and 2Ey in FIG.
3a.
[0070] Since the course of warp thread Kx illustrated in FIG. 3a is
representative of all the warp thread courses K1-K5, each
overlapping region U1-U5 in belt 4 illustrated has the same number
of second transverse threads.
[0071] FIG. 3b shows the five overlapping regions U1 to U5
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 U1 and U2 is determined by the
distance between the end 2E1 of the overlapping region U1 and the
end 1E2 of the overlapping region U2. Furthermore, for instance,
the offset between the two consecutive overlapping regions U2 and
U3 is defined by the distance between the end 2E2 of the
overlapping region U2 and the end 1E3 of the overlapping region U3.
The principle is continued in the further overlapping regions.
[0072] 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.
[0073] 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.
[0074] 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 U1 to U35. 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 U1 to U35 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 U1 and U2 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.
[0075] 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 U1 to U9 following one another in each case
have the same offset in relation to one another.
[0076] 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.
[0077] The longitudinal extent of connecting region 22, defined by
the two overlapping regions U34 and U35 which, as viewed in the MD,
are spaced furthest apart from each other, is 60 cm.
[0078] The belt is permeable and in the present case has a
permeability of 750 cfm.
[0079] 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 Ua to Ue extend.
[0080] 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.
* * * * *