U.S. patent application number 11/148777 was filed with the patent office on 2006-12-14 for hybrid warp exchange triple layer forming fabric.
This patent application is currently assigned to Voith Fabrics Patent GmbH. Invention is credited to Scott Quigley.
Application Number | 20060278294 11/148777 |
Document ID | / |
Family ID | 36942206 |
Filed Date | 2006-12-14 |
United States Patent
Application |
20060278294 |
Kind Code |
A1 |
Quigley; Scott |
December 14, 2006 |
Hybrid warp exchange triple layer forming fabric
Abstract
A fabric for papermaking usable in the forming section of a
paper making machine, having a first weft system, a second weft
system and a third weft system; and a plurality of warp systems,
each warp system having at least one warp yarn, each warp yarn
binding with one of the first weft system, the third weft system,
the first and second weft systems, and the second and third weft
systems; wherein a first warp system is an exchange warp
system.
Inventors: |
Quigley; Scott; (Bossier
City, LA) |
Correspondence
Address: |
Voith Fabrics
P.O. Box 1411
Wilson
NC
27894-1411
US
|
Assignee: |
Voith Fabrics Patent GmbH
|
Family ID: |
36942206 |
Appl. No.: |
11/148777 |
Filed: |
June 8, 2005 |
Current U.S.
Class: |
139/383A |
Current CPC
Class: |
D21F 1/0045
20130101 |
Class at
Publication: |
139/383.00A |
International
Class: |
D03D 25/00 20060101
D03D025/00 |
Claims
1. A fabric for papermaking comprising: a first weft system, a
second weft system and a third weft system; and a plurality of warp
systems, each warp system having at least one warp yarn, each warp
yarn binding with one of the first weft system, the third weft
system, the first and second weft systems, and the second and third
weft systems; wherein a first warp system is an exchange warp
system.
2. The fabric for papermaking of claim 1, wherein the first weft
system is one of a paper side weft, a wear side weft and an
intermediate weft.
3. The fabric for papermaking of claim 1, wherein each warp system
is independent.
4. The fabric for papermaking of claim 1, wherein mesh density of
the first weft system and the second weft system is independent
from a mesh density of the third weft system and the second weft
system.
5. The fabric for papermaking of claim 1, wherein the fabric is
fabricated using a plurality of shafts ranging from 4 to 56.
6. The fabric for papermaking of claim 1, wherein the first weft
system has a first yarn having a first diameter, the second weft
system has a second yarn having a second diameter and the third
weft system has a third yarn having a third diameter.
7. The fabric for papermaking of claim 1, wherein the at least one
warp yarn has a fourth diameter.
8. The fabric for papermaking of claim 1, wherein the yarn is one
of a mono filament and a twisted pair.
9. The fabric for papermaking of claim 1, wherein warp repeats
range from 2 to 112.
10. The fabric for papermaking of claim 1, wherein the fabric is
fabricated using a loom having at least three warp beams.
11. A fabric for papermaking comprising: a first weft system, a
second weft system and a third weft system, the second weft system
between the first and third weft systems; and a plurality of warp
systems, each warp system having at least one warp yarn, each warp
yarn binding with the second weft system and one of the first and
third weft systems.
12. The fabric for papermaking of claim 11, wherein the first weft
system is one of a paper side weft, a wear side weft and an
intermediate weft.
13. The fabric for papermaking of claim 11, wherein each warp
system is independent.
14. The fabric for papermaking of claim 11, wherein mesh density of
the first weft system and the second weft system is independent
from a mesh density of the third weft system and the second weft
system.
15. The fabric for papermaking of claim 11, wherein the fabric is
fabricated using a plurality of shafts ranging from 4 to 56.
16. The fabric for papermaking of claim 11, wherein the first weft
system has a first yarn having a first diameter, the second weft
system has a second yarn having a second diameter and the third
weft system has a third yarn having a third diameter.
17. The fabric for papermaking of claim 11, wherein the at least
one warp yarn has a fourth diameter.
18. The fabric for papermaking of claim 11, wherein the yarn is one
of a mono filament and a twisted pair.
19. The fabric for papermaking of claim 11, wherein warp repeats
range from 2 to 112.
20. The fabric for papermaking of claim 11, wherein the fabric is
fabricated using a loom having at least three warp beams.
Description
CROSS-REFERENCE TO RELATED APPLICATIONS
[0001] Not Applicable.
STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH OR DEVELOPMENT
[0002] Not applicable.
REFERENCE TO A COMPACT DISK APPENDIX
[0003] Not applicable.
BACKGROUND OF THE INVENTION
[0004] 1. Field of the Invention
[0005] The invention relates to a fabric used in papermaking. More
specifically, the present invention relates to forming fabrics used
in the forming section of a papermaking machine.
[0006] 2. Description of Background
[0007] In the art of papermaking, multiple steps occur from the
introduction of a pulp slurry to the output of a finished paper
product. The initial introduction of the slurry is at the portion
of a papermaking machine known as the wet end. Here, the slurry, or
fiber suspension, is initially dewatered when the slurry is
introduced onto a moving forming fabric, in the forming section of
the papermaking machine. Varying amounts of water is removed from
the slurry through the forming fabric, resulting in the formation
of a fibrous web on the surface of the forming fabric.
[0008] Forming fabrics address not only the dewatering of the
slurry, but also the sheet formation, and therefore the sheet
quality, resulting from the formation of the fibrous web. More
specifically, the forming fabric must simultaneously control the
rate of drainage while preventing fiber and other solid components
contained in the slurry from passing through the fabric with the
water. The role of the forming fabric also includes conveyance of
the fibrous web to the press section of the papermaking
machine.
[0009] Additionally, if the drainage occurs to rapidly or too
slowly, the quality of the fibrous web is reduced, and overall
machine production efficiency is reduced. Controlling drainage by
way of fabric void volume is one of the fabric design criteria.
[0010] Forming fabrics have been produced to meet the needs and
requirements of the various papermaking machines for the various
paper grades being manufactured. As the needs arises to increase
production speed of the papermaking machines and the quality of the
paper being produced, the need for improved paper machine clothing
allowing for increase production rates and improved quality
resulted.
BRIEF SUMMARY OF THE INVENTION
[0011] Accordingly, the present invention is for a fabric used in
papermaking, and more particularly, as a forming fabric. In the
preferred embodiment, the fabric is a hybrid warp exchange triple
layer forming fabric. The fabric has a first weft system, a second
weft system and a third weft system, the second weft system between
the first and third weft systems. In the finished fabric, the
second and third weft systems are preferably in the same plane. The
fabric also has a plurality of warp systems, each warp system
having at least one warp yarn. Each warp yarn binds with one of the
first weft system, the third weft system, the first and second weft
systems, and the second and third weft systems. A first warp system
is an exchange warp system. Generally, machine direction (MD) yarns
are warp yarns, and cross machine direction (CMD) yarns are weft
yarns.
[0012] A weft system is a system of wefts that performs a function.
As such, the first weft system can be a paper side weft, a wear
side weft or and intermediate weft. In the preferred embodiment,
the intermediate weft acts as a binding layer. Still further, the
mesh density of the first weft system and the second weft system is
independent from the mesh density of the third weft system and the
second weft system.
[0013] Still further, the first weft system has a first yarn, the
first yarn having a first diameter. Likewise, the second weft
system has a second yarn, the second yarn having a second diameter,
and the third weft system has a third yarn, the third yarn having a
third diameter. The weft and warp yarn materials include, but are
not limited to mono filament yarns, synthetic or polyester mono
filament yarns, twisted mono filament yarns, twisted synthetic or
twisted polyester or twisted polyarnide mono filament yarns,
twisted multi-filament yarns, twisted synthetic or twisted
polyester multi-filament yarns, and others. Various yarn profiles
can be employed, including but not limited to yarns having a
circular cross sectional shape with one or more diameters, or other
cross sectional shapes, for example, non-round cross sectional
shapes such as oval, or a polygonal cross sectional shapes, for
example diamond, square, pentagonal, hexagonal, septagonal,
octagonal, and so forth, or any other shape that the yarns may be
fabricated.
[0014] Still further, each warp system can be independent. Each
warp layer, has at least one warp yarn, and the at least one warp
yarn has a fourth diameter.
[0015] Additionally, each warp system has a predetermined number of
warp repeats, ranging from 2-112, preferably 2-28.
[0016] The triple layer forming fabric of the present invention has
exchange warps that do not bind with larger diameter bottom wefts.
Rather, they bind with a smaller diameter intermediate weft. All of
the warp yarns can be the same diameter or there can be two
different warp yarn diameters. In contrast, the warp yarns in the
prior art fabrics must all be of the same diameter.
[0017] As a result, the exchange points can be spread out farther
than the prior art, resulting in a less obvious pattern. This can
be done because the bottom warps bind with the intermediate wefts
between the exchanges.
[0018] The warp that weaves only on the bottom, or wear side of the
fabric can be of a larger diameter than those that weave on the
top, or paper side of the fabric. In this manner the modulus of the
fabric is enhanced, and allows for larger diameter bottom wefts to
be employed.
[0019] In another embodiment, the fabric has a first weft system, a
second weft system and a third weft system, the second weft system
between the first and third weft systems. The fabric also has a
plurality of warp systems, each warp system having at least one
warp yarn. Each warp yarn binds with one of the second weft system
and one of the first and third weft systems.
[0020] It is also understood that there are no limitations to the
paper grades or former types where this invention can be applied.
It is also understood that the fabric can be woven utilizing either
two or three warp beams.
[0021] These and other features and advantages of this invention
are described in or are apparent from the following detailed
description of the preferred embodiments.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] The preferred embodiments of the present inventions will be
described in detail, with reference to the following figures,
wherein:
[0023] FIGS. 1A-1B depict a cross-sectional view of a triple layer
fabric having a 2:1 warp ratio and a two shed/three shed
arrangement according to the present invention;
[0024] FIG. 2 depicts a forming side plan view of a triple layer
fabric having a 2:1 warp ratio and a two/three shed arrangement
according to the present invention;
[0025] FIGS. 3A-3B depict a cross-sectional view of a triple layer
fabric having a 2:1 warp ratio and a three shed/three shed
arrangement according to the present invention;
[0026] FIG. 4 depicts a forming side plan view of a triple layer
fabric having a 2:1 warp ratio and a three/three shed arrangement
according to the present invention;
[0027] FIGS. 5A-5C depict a cross-sectional view of a triple layer
fabric having a 2:1 warp ratio and a two shed/four shed arrangement
according to the present invention;
[0028] FIG. 6 depicts a forming side plan view of a triple layer
fabric having a 2:1 warp ratio and a two shed/four shed arrangement
according to the present invention;
[0029] FIGS. 7A-7C depict a cross-sectional view of a triple layer
fabric having a 2:1 warp ratio and a two shed/six shed arrangement
according to the present invention; and
[0030] FIG. 8 depicts a forming side plan view of a triple layer
fabric having a 2:1 warp ratio and a two shed/six shed arrangement
according to the present invention.
DETAILED DESCRIPTION OF THE INVENTION
[0031] FIGS. 1A-1B depict a cross-sectional view of a triple layer
fabric 10 having a 2:1 warp ratio and a two shed/three shed
arrangement according to the present invention, fabricated on a two
beam loom. FIG. 2 depicts the forming side plan view of the same
fabric 10.
[0032] A first weft system 12 is shown above a second weft system
14. The first and second weft systems 12, 14 are shown above a
third weft system 16. Each weft system 12, 14, 16 is made up of a
plurality of yarns 18, 20, 22. First weft yarn 18 has a first yarn
diameter, second weft yarn 20 has a second yarn diameter, and third
weft yarn 22 has a third yarn diameter. The first, second and third
yarn diameters 18, 20, 22 can be the same or different. Different
size numerals for each of the different weft layer yarns 18, 20, 22
is indicative of a different weft yarn diameter in the preferred
embodiment.
[0033] The first, second and third weft systems 12, 14, 16 are
bound together by a plurality of warp systems 24. FIGS. 1A-1B show
fifteen warp systems 24 in a repeating pattern. Each warp system 24
has at least one warp yarn 26, and each warp yarn 26 is woven in a
two shed/three shed repetition.
[0034] The weft and warp yarn materials include, but are not
limited to mono filament yarns, synthetic or polyester mono
filament yarns, twisted mono filament yarns, twisted synthetic or
twisted polyester or twisted polyarnide mono filament yarns,
twisted multi-filament yarns, twisted synthetic or twisted
polyester multi-filament yarns, and others. Various yarn profiles
can be employed, including but not limited to yarns having a
circular cross sectional shape with one or more diameters, or other
cross sectional shapes, for example, non-round cross sectional
shapes such as oval, or a polygonal cross sectional shapes, for
example diamond, square, pentagonal, hexagonal, septagonal,
octagonal, and so forth, or any other shape that the yarns may be
fabricated into.
[0035] This first warp yarn 26 binds the top, or first weft 12 with
the middle, or second weft 14. A second warp yarn 30 also binds the
top, or first weft 12 with the middle, or second weft 14. The first
and second warp yearns 26, 30 form what is called an exchange warp.
An exchange warp is, for example, when one member of a pair of warp
yarns 26, 30 is weaving with the first weft system 12 and the other
member of the pair of warp yarns 26, 30 is weaving with the second
weft system 14. Stated differently, an exchange warp allows for one
warp yarn of a pair of warp yarns to weave in alternate fashion
such that when the first warp yarn 26 is weaving with a first weft
system 12, the second warp yarn 30 is not weaving with the first
weft system 12, and both the first and the second warp yarns are
not weaving the same weft at the same time.
[0036] In the present invention, while depicting a plurality of
warp systems 24, some yarns of the warp systems form exchange warp
pairs and some of the warp systems do not form exchange warp pairs.
In FIG. 1, for example, the first warp yarn 26 and the second warp
yarn 30 form the first warp system 28, which is an exchange warp
pair. In contrast, warp yarn 32 forms a second warp system 34.
Accordingly, warp yarn 32 does not cross the second warp yarn 30 of
the first warp system 28, and no exchange warp is formed.
[0037] FIG. 2 depicts the forming side plan view of the triple
layer fabric 10 having a 2:1 warp ratio and a two shed/three shed
arrangement according to the present invention. In this example, it
can be readily seen that the first and second warp yarns 26, 30
form a first warp system, and therefore a warp pair that forms an
exchange warp. The x notation marks where the first warp yarn 26
appears in the forming side view forming a knuckle, and y indicates
where the second warp yarn 30 appears in the forming side view
forming a knuckle. The third warp yarn 32, since it only binds the
second weft system 14 with the third weft system 16, does not
appear in the forming side plan view. The boxes with forward slash
fill denote where warps exchange, and boxes with grey fill denote
locations of bottom side warp knuckles. Since the invention is
directed to a triple layer fabric, the weave has a separate forming
or paper side and a wear side.
[0038] This pattern repeats throughout the forming side plan view.
For example, a fourth warp yarn 36 forms an exchange warp with a
fifth warp yarn 38. Similarly, a sixth warp yarn 40 forms a warp
exchange with a seventh warp yarn 42. An eighth warp yarn 44 does
not form an exchange warp with another yarn. FIGS. 1A-1B further
show a ninth warp yarn 46, a tenth warp yarn 48, and eleventh warp
yarn 50, a twelfth warp yarn 52, and thirteenth warp yarn 54, a
fourteenth warp yarn 56, and a fifteenth warp yarn 58. Accordingly,
FIG. 2 depicts fifteen warp repeats, with six pairs of exchanging
warps and 3 bottom warps. The pattern repeats in both the forming
side and the wear side layers. The double forward slashed areas in
FIG. 2 show the crossover points of the warp exchange yarns below
the forming side surface. The single grey areas in FIG. 2 show the
warp yarn exposure on the wear side, that is, a wear side knuckle,
not shown.
[0039] Accordingly, the views in FIGS. 1A-1B and 2 show one
complete pattern in the machine direction.
[0040] FIGS. 3A-3B depict a cross-sectional view of a triple layer
fabric having a 2:1 warp ratio and a three shed/three shed
arrangement according to the present invention. FIG. 4 depicts the
forming side plan view of the triple layer fabric having a 2:1 warp
ratio and a three shed/three shed arrangement according to the
present invention. As in FIGS. 1A-1B and 2, the first warp yarn 26
forms an exchange warps with the second warp yarn 30. The
difference is that the first and second warp yarns 26, 30 have a
three shed weave pattern.
[0041] FIGS. 5A-5C depict a cross-sectional view of a triple layer
fabric having a 2:1 warp ratio and a two shed/four shed arrangement
according to the present invention, and FIG. 6 depicts the forming
side plan view. Twenty-four warp yarns are shown as 118, 120, 122,
124, 126, 128, 130, 132, 134, 136, 138, 140, 142, 144, 148, 150,
152, 154, 156, 158, 160, 162 and 164. In this embodiment, an
additional warp is added that only binds to the top, or first weft
system 112, and does not bind with the second or third weft systems
114, 116. These top binding only warps are designated 118, 126,
134, 142, 150 and 158. The boxes in FIG. 6 with the reverse hash
fill indicate locations where the bottom warp binds with the
binding weft, or the second weft system.
[0042] FIGS. 7A-7C depict a cross-sectional view of a triple layer
fabric having a 2:1 warp ratio and a two shed/six shed arrangement
according to the present invention, and FIG. 8 depicts the forming
side plan view. Twenty-four warp yarns are shown as 218, 220, 222,
224, 226, 228, 230, 232, 234, 236, 238, 240, 242, 244, 246, 248,
250, 252, 254, 256, 258, 260, 262 and 264. In this embodiment, the
fabric 10 is woven using a three beam configuration, and has a
different weave pattern than that depicted in FIGS. 5-6. This
pattern shown in FIG. 8 has the additional notation of boxes
containing horizontal or vertical fill lines, representing
locations where an exchanging warp binds at the second weft layer
according to the cross-sectional view of FIGS. 7A-7C.
[0043] The invention has been described that can be fabricated on a
three beam loom. Likewise, the triple layer fabric of the present
invention can also be fabricated on a four beam loom. Use of four
beams could result in similar fabrics, with the addition of at
least one of a top only warp, a bottom only warp, a bottom warp
that binds at the second weft system, and a top pair that binds
with the second weft system.
[0044] While the present invention has been particularly shown and
described with reference to the foregoing preferred embodiments,
those skilled in the art will understand that many variations may
be made therein without departing from the spirit and scope of the
invention as defined in the following claims. This description of
the invention should be understood to include all novel and
non-obvious combinations of elements described herein, and claims
may be presented in this or a later application to any novel and
non-obvious combination of these elements. The foregoing
embodiments are illustrative, and no single feature or element is
essential to all possible combinations that may be claimed in this
or a later application. Where the claims recite "a" or "a first"
element or the equivalent thereof, such claims should be understood
to include incorporation of one or more such elements, neither
requiring nor excluding two or more such elements.
* * * * *