Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
1 3 1 ~830
,
1 Background of the Invention
The invention is directed to a method of manufacturing
an insertion-type seam for making a cloth belt especially
a wire cloth or a paper-making fabric endless. The
invention is also directed to a seaming machine for
carrying out the method.
Cloth belts of the above-specified type comprise
especially dehydration or dryer wire cloths. As compared
to endless-woven wire cloths or wire cloths made endless
by a woven seam, wire cloths with an insertion-type
seam offer the advantage that they may be made endless
in the suction extractor or in the dryer section of the
paper-making machine itself by joining the two prepared
cloth ends by means of an insertion wire. Up to now,
these insertion-type seams have been prepared manually
by re-weaving or re-splicing ~he warp threads of ~ach
cloth side of two c10th ends ~o be joined by a seam, so
that a series of warp thread loops is formed on each side
through which then the common joining insertion-wire
may be passed.
This preparation of such an insertion-type seam which is
described in European Patent û043441 and German Utility
Model 81 22 45l, with regard to making dehydration wire
cloths with one seam endless, is very labour-consuming
and expensive since it is performed manually.
Sum ~ ~ iion
It is therefore an object of the invention to provide a
method, and it is a further object of the invention to
provide a machine, permitting mechanization and
automation of the intricate and time-consuming manual
work, whereby a significant relief of personnel and
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1 thus an increase in productiveness and an improvement in
the quality of insertion-type seams can be achieved.
These and other objects of the invention are accomplished
in that the warp ends after unravelling of the right-hand
and the left-hand cloth side are strung in a magazining
bunch, and mechanically individually separated in accordance
with the weaving order and alternatingly returned and re-
woven about a central wire of any desired cross-sectional
area, said central wire being disposed in the center of the
auxiliary warp strip and consisting of at least one wire,
so that in accordance with the weaving progress a warp end
of the right-hand and the left-hand cloth side alternately
winds about the central wire, while the respective opposite
warp is re-woven without being looped about the central
wire, the warp ends after insertion into the shed made in
accordance with the weaving order being beaten up in paral-
lel to the selvedge.
According to another mode of operation, the method of the
invention resides in that the warp ends, after unravelling
of the right-hand and left-hand cloth ends, are strung to
form a magazining bunch, mechanically separated in accord-
ance with the weaving order and individually respectively
re-woven about a loop of a wire helix, wherein when two wire
helices are used the same are disposed in parallel and are
not interconnected, and wherein the left-hand and the right-
hand cloth ends are retained in such a way that any lateral
slipping or displacement is prevented. Thereafter, the wire
helices are interconnected by means of a common inserted
wire externally of the seaming machine.
According to a further proposal, the method of the
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invention resides in that the warp ends~ after unravelling
of the right-hand and left-hand cloth ends, are strung to
form a magazining bunch, and mechanically separated in ac-
cordance with the weaving order and individually respect-
ively re-woven about a loop of a wire helix, wherein when
two wire helices are used the same are disposed in paral-
lel fitted into each other, and wherein progressing with
the seam a central wire is fit into both helices, connect-
ing them and thus both cloth ends with each other such
that lateral slipping between both cloth ends and on the
seaming machine is prevented.
.
To perform the method according to the invention a seam-
ing machine is used which is characterized by separators
disposed on either side of the insertion-type seam to be
made for removing and separating the warp ends from the
warps of each cloth side which are arranged in magazining
bunches, a gripper system comprising transfer grippers and
drawing-in grippers for inserting the separated individual
threads into a shed preformed from auxiliary warps by a
shedding mechanism, the individual threads adapted to be
beaten up to the respective selvedge within said shed by
a driven lathe respectively provided for each seaming half,
wherein subsequent to beating-up the individual threads
are re-woven by means of the gripper system either about
one or several central wires or wire helices or, avoiding
the central wire or wires or wire helices directly into
their own side of the cloth.
Additional objects, features and advantages of the
invention will become apparent from the subclaims.
131~830
1 Brief Description of the Drawings
.
The invention will be described in detail hereinbelow
with reference to the embodiments thereof illustrated
in the drawings, in which
Fig. 1 is a schematic isometric front view of the
seaming machine according to the invention,
Fig. 2 is a reduced-scale end view of the machine
illustrated in Fig. 1, in which the cloth
belt that is to be made endless is passed
like a tent across the seaming machine,
Fig.2a is a detailed side view of the device for the
connection and disconnection of the drive motor
of the seaming machine,
Fig. 3-5 are schematic views showing the operating
steps when making the insertion-type seam for
one cloth side,
Fig. ~ is a schematic plan view of the
seam of the right-hand and the left-hand
cloth sides to be joined by means of a
central wire,
Fig. 7 is a plan view similar to Fig. 6, in which
however two parallel inserted wires are used
instead of a single central wire,
Fi9. 8 is a plan view of a cloth end having a wire
helix interwoven therein, each warp thread end
being tied up in the helix,
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1 Fig. 9 is a cross-sectional view of two cloth ends
each prov;ded with a wire helix, said cloth
ends being positioned by means of a device
including guide rollers,
Fi9. 10 is a plan view similar to Fig. 8 of a cloth
end in which the wire helix is woven-in together
with a wire placed therein.
Fig. 11 is a plan view of two cloth ends each having
a wire helix interwoven therein and a partially
inserted central wire,
Fig. 12 is a sectional view of the seaming machine shown
in Fig. 1 in a longitudinal direction along a
line of symmetry,
Fig. 13 is a cross-sectional view of the seaming machine
shown in Fig. 1,
Fig. 14 is a general view of the seaming machine with
travelling mechanism and single thread suspension,
Fig. 15 is an isometric view of an assembly comprising
thread separators, transfer grippers and holding-
down device,
Fig. 16 is a view of the major parts of the thread
separator assembly,
Fig. 17 is a side view and a front view of the transfer
gripper assembly,
Fig. 17a is a sectional view of the head of a transfer
gripper,
Fig. 18 is a ~ide view and a ~lan view of the threading
gripper assembly,
1 3 1 8 8 3 0
Fig~ 18a is a sectional view of the head of the threading
gripper.
Fig. 19 is a view of both lathes, and
Fig. l9a is a side view of a lathe according to arrow A
in Fig. 19.
Detailed Description of the Pre~e,rred Embodiments sf the
Present Invention
As ~ill be apparent from Figures 1, 12 - 14, the seaming
machine comprises essentially a travelling mechanism 1,
1~ guided by a frame 3, 4, 4' and mounted on the travelling
mechanism there is a jacquard head 40, a harness 50, a
single thread suspension 60, a thread separator 7, 7', a
trans~er gripper 8, 8', a threading gripper 9, 9', a
lathe 10, 10', a control console 70, an electric-control
unit 80 and a pneumatic-control unit 90.
Referring to Figures 1, 12 and 13, the travelling
mechanism 1 includes a frame body 31 movable on wheels
30, said frame body being adapted to be moved via a
controlled drive motor 2 with the rhythm o~ the weaving
progress. The traveIling mechanism 1 is a welded
structure and serves to support a machine table 32, the
above identified units as well as the feed unit 35 during
the weaving process. The travelling mechanism 1 can be
driven automatically with a gear-break motor 2 followed
by a ~igh reduction gear 37. Thus for instance a feed of
0.01575 inch/sec (0.4 mm/sea) can be achieved. The feed
of the seaming mach~ne is controlled dependent on the
density of the cloth, whereby the duration of the moving
pulse is to be entered in the program by means of a timer
depending on warp count division. Without the weaving
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program the seaming machine can be run by means of the
gear-motor 2, 37 with push buttons connected therewith in
a ~orward and a backward direction. The forward
direction concurs with the seaming direction. This mode
of operation has been provided for travelling across
short distances e.g. for the start up of a weaving
process or during the occurrence of a fault. If it is
necessary to shift the seaming machine over larger
distances, as would be the case when a seam is finished
and a wire removed, to return the seaming machine into
the start position, then the gear-break motor 2, 37 can
be disconnected. This can be done by means of a device
36 comprising a star handle screw 38. The seaming
machine can then be moved manually. To disconnect the
gear-break motor 2, 37 the star handle screw 38 (Fig. 2a~
is slackened, while the gear-break motor 2, 37 is held
firmly until the screw 38 is free. Then the g&ar-break
motor 2 is pushed downwards on its hinge in the direction
of arrow B. ~he worm gear 36a is then disconnected. For
automatic operation the gear-break motor 2 is pushed
upward on its hinge and the seaming machine is moved
sideways until the worm 36a engages in the worm wheel
36b. Following this the star handle screw 38 can be
retightened.
The frame consists in general of two stands 4, 4' and two
supporting- and guiding tubes 3 as well as for wide and
heavy wire cloth additionally of one or two intermediate
pillars 4a for the support o~ the supporting tubes 3.
The frame body 31 of the travelling mechanism is guided
on either side below the working plane of the machine by
the two parallel supporting- or guiding tubes 3 the ends
of which are in turn mounted on a horizontal cross-tie or
machine table 32 of the frame or stand 4. In general the
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1 3 1 883~
- 7a -
stand 4 does not comprise wheels and is located on that
side of the seaming machine, where the start-up of the
seaming takes place. The stand 4 has the function of
guiding and clamping of
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1 the supporting tubes 3 as well as the clamping of the
auxiliary warp threads respectively auxiliary warp strips
15, 15' and the central wire 16. The stand 4 serves
furthermore for the mounting of deflection pulleys 13a
for loading the magazining bunches 13, 13', for attachment
of the connecting socket for the power supply and for
the attachment of a compressed-air spiral tube. In a
further embodiment the stand 4' has four steering rollers
4b and 4c whereby the steering rollers 4b are provided
with breaks which can be locked during operation of
the seaming machine. The stand 4' also has the function
of guiding and clamping of supporting tubes 3 as well as
the clamping of maga~ining bunches 13, 13'.
The jacquard head 40 known in the art is mounted centrally
on the traveling mechanism 1. The jacquard head 40 can
for example be designed for 216 threads whereby 198 threads
can be used, when the first two and the last rows of
the jacquard cards are left free in the jacquard head.
The first two rows of the jacquard cards44 are required
for controlling a double needle 7a of the thread separator
7, 7'. The last row of jacquard cards can be omitted in
order to improve the shed geometry. As change device 46
for the central wire 16 a pneumatic cylinder 452 is ~~
mounted on brackets 51. The central wires 16 are controlled
by signals included in the weaving program. Besides the
automatic operation of the jacquard head 40 it can be
operated manually with respective switches and push
buttons. By means of these push buttons a manual change
of shed can be accomplished.
The harness 50 is fitted with 198 threads for the
example given above. That means that seams with a maximum
of 198 threads can be made. For seams with a smaller
number of auxiliary warp threads 15, 15', the threads
should be divided symmetrical in the center of the
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1 3 1 8~30
harness 50 and if required every third or fourth harness
eye 52 should be left Pree, dapending on the numher of
auxiliary warp threads. The basic tensic)n of the harness
springs 53 can be altered by raising or lowering the base
of the spring 54.
~he single thread suspension 60 is shown detailed in
Figure 14. Thus each auxiliary warp thread 15, 15' is
provided with a weight 62. For this purpose the
auxiliary warp thread 15, 15' is connected to the
Gonnectiny thread 63 of the weight 62 by a special
coupling ~4 after threading into the harness eye 52. In
one embodiment the weights 62 are made from brass. With
a diameter of ~ mm a weight 62 having a length of 600 mm
weights approximately 65 g.
Referring to Figures 1, 12-14 and 16, the thread
separators 7, 7' are mounted via a bracket 51 on the
travelling mechanism 1 like the above-mentioned shedding
mechanism 5 (see Figures 3-5) respectively to the
jacquard head 40. The warp threads 12, 12' chosen to be
woven are released by the thread separator 7, 7' one-by-
one from the magazining bunrh 13, 13' and positioned for
the transfer gripper 8, ~'. The force oX the separating
head 7b is determined by a spring 7c, which is connected
to a pneumatic cylinder 7d~ The thread separators 7, 7'
can be adjusted horizontally and vertically with knurle
screws 7e. The entire mechanism 7 to 7e and 8 to eg can
be turned into an upper position thus allowing free
access to tha seam area. The size of the separating
needles 7a, which are provided with two hooks 7g, 7g',
for the separation of threads for fine cloth consisting
of multiple layers depends on the profile of the warp
A
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threads 12, 12~ The depth of the hook 7a for round warp
threads could always be 25 to 30% less than the diameter
of the warp threads. Oval and rectangular warp threads
raquire specially adapted separating needle~ 7a. The
thread separator 7, 7' can be operated automatically as
well as manually. The same holds true for the device for
the tensionin~ of the thread separators 7f respeative of
the motion o~ the separating needles 7a.
~he bracket 51 has also secured thereto thread separators
7, 7' and transfer grippers 8, ~'. As it is the case for
; the thread separators 7, 7' there is one transfer gripper
8 and 81 respectively provided each for one of both cloth
halves, wherein the primed reference numerals relate to
one cloth half and the n~n-primed ones relate to the
opposite second cloth half. The transfer grippers 8, 8'
take the single thread 12a off the thread separator 7, 7'
to the threading gripper 9, 9' being in a ready position.
The transfer grippers 8, 8' are driven by pneumatic
rotary drives 8a lFig. 15). The angle of swing of the
transfer grippers 8, 8' can be adjusted continuously by
means o-~ stop screws 8b. For the proper control of end
positions electronic indicators 8c are mounted on the
stop screws 8b. For an adjustment of the end positions
of the transfer grippers 8, 8' said screws are loosened
on the electronic indicator elements as well as lock nuts
8e on the stop screws 8b. FQ110Wing this the turning
angle and thus the position of the transfer grippers 8,
8' can be adjusted with the stop screws 8b. The transfer
gripper tensioners 8f are equipped with eleatric contacts
8g. If a t~read 12a is missing the control system
switches into a fault condition such that the operation
o~ the seaming machine is holded. For the insertion o~ a
1 31 8830
mlssing thread 12a in the transfer gripper tensioner 8~
(Fig. 17a) the tensioner can be held open through a push
button and a switch as long as it is necessary to insext
a thread by hand. In order to keep the beating-up line
and the seam in the area where it is processed in the
same level as the cloth a holding-down device 8d is
provided for as shown in Figure 15.
Underneath the working plane of the seaming machine are
the threading grippers g, 9' (Fig. 18) as well as the two
lathes 10, 10' tFig. 19~, The drawing-in grippers 9, 9'
serve mainly two functions namely taking the warp thread
ends 12, 12' off the trans~er grippers 8, ~' and entering
these auxiliary weft threads in the alternately opened
sheds 5a, 5b, 5c of the seam and further the reciprocal
transfer of the warp thread ends 12, 12~ which are woven
back. The drawing-in grippers 9, 9' are driven by
pneumatic rotary drives 9a with end position indicator 9b
and installed cylinders 9c for intermediate positions 9d.
The end positions ge o~ the drawing-in grippers 9, 9' can
be adjusted continuously by means of stop screws 9f. The
indicator elements 9b are fastened to the stop screws 9f
and must be removed prior to an adjustment of the stop
screws 9f. To confirm intermediate positions 9d, cams 9h
are fitted to bottom shaft ends 9g of the drawing-in
grippers 9, 9'. When the intermediate position 9d is
reached the cams 9h trigger approximation initiators 9i.
For the adjustment of intermediate positions 9d the
seaming machine is switched off with the master switch.
Following this compressed air conneations 9j at the
cylinder bottom 9k as well as lock nuts 91 at the
cylinder neck gm have to be disconneated. Then the
desired position 9d is set by turning the cylinder 9c.
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1 3 1 8830
A$terwards the air connections 9j and the lock nuts 91
are retightened and ~hen the cams 9h are readjusted for
the confirmation of the intermediate position 9d. ~he
gripper heads 9n ~Fig. 18a) are equipped with electrical
contacts 9p which in lack of a thread transmit a signal
to the m~chine control system to switch the machine into
a fault condition.
Within the seaming machine two lathes 10, 10' are mounted
as shown in Figures 19, l9a whereby one is located at the
operating side and the other one on the back side. The
lathes 10, 10' are driven by pneumatic cyli~ders lOa.
These are equipped with throttle valves lOb ~or speed
adjustment of the lathes 10, 10'. The lathe reed lOc
must be individually made up for each cloth from
respective dents lOd and spacer discs lOe. It may then
beco~e necessary to pull through more than one auxiliary
warp threads 1~, 15' per opening 10~.
The bracket 6 mounts furthermore switching- and
controlling devices which are necessary for the operation
of the seaming machine and arranged in a control console
70. The switching- and indication devices arranged in
the control console 70 ~erve the activation and control
o~ gear-break motox 2, 37, the jacquard head 40, the
shedding device, the thread separator 7, 7' and the
~5 thread separator tensioner 7f, the transfer gripper 8, 8'
and the transfer gripper tensioner as well as the
drawing-in gripper 9, 9' and the drawing-in gripper
tensioner. Furthermore, a selector switch for automatic
and single step operation and a push button ~or emergency
stop are installed.
1 31 ~830
- 12a -
The electric control unit 80 contains the main switch,
clrcu.it-breaker, contactors and a storaqe-proqrammable
controlling unit.
The pneumatic control unit 90 contains valves for all
grippers 7, 7', 8, 8', 9, g', lathes 1~, 10 r ~ insertion
wires and shedding mechanism.
In Fig~ 1, t~e wire cloth 11 to be provided with an
insertion-type seam passes beneath the seaming machin~e,
i.e~, the machine travels on the wirP cloth which is
1 31 8830
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1 covered with a protective layer~ An alternative way of
guiding the wire cloth 11 is shown in Fig. 2, where the
wire cloth is passed like a tent via two supporting
rods 23, 24 across the seaming machine.
Prior to being placed in the seaming machine, the two
ends 21, 22 of the wire cloth 11 to be provided with an
insertion-type seam are prepared by removal of the
wefts in a region having a width of ca. 10 to 20 cm,
whereupon 10 to 30 wefts, depending on the weave, are
combined on the warp ends 12, 12' in their exact
weaving position to form a magazining bunch 13, 13'. The
magazining bunches 13, 13' are secured by clamping means
14 at the end stands 4, 4' of the traveling mechanism 1,
only one of said stands being illustrated in Fig. 1.
Before the seam is made, a group of wires which may
either consist of original wefts of the cloth or may be
a strip 15, 15' also called auxiliary warp strip con-
sisting of original wefts of the cloth and constitutingthe warp for the seam-weaving process performed trans-
versely to the actual direction of the wire cloth, is
positioned on either side of the wire 16 which is
called central wire between the two unravelled ends of
the wire cloth 11, said ends being held by the
magazining bunches 13, 13'. The central wire 16 is
located exactly midway between the two auxiliary warp
strips 15, 15'. The auxiliary warp strips and the
central wire are secured in a further clamping means 17
of the machine likewise mounted on the stands 4, 4'.
The individual wires of the auxiliary warp as well as
the central wire 16 are guided in eyelets of the shedding
mechanism or jacquard head 40 disposed either above or
below the plane of weaving on the traveling mechanism 1.
1 31 8830
, ~
1 Removal and separatiOnO the warp ends 12, 12' (Fig. l) by
means of the thread separators 7, 7' is effected in a
manner known per se, identical seam forming elements
such as thread separators 7, 7', transfer grippers 8, 8',
drawing-in grippers 9, 9' and lathes lO, 10' being provided
on either side of ~he seam. Initially, the transfer
gripper 8' grips the warp separated by the thread
separator 7' and swings it downward to the transfer
position of the working plane, as will be apparent from
Fig. 3. Then the drawing-in gripper 9 takes over the
warp end and pulls the warp into the full shed fQrmed
by the shedding mechanism 40. Thereupon, the thus in-
serted warp end is beaten up to the selvedge by the lathe
lO'. Now, theright-hand part of the auxiliary warp strip l5
TOrmS an inner partial shed, as will be apparent
from Fig. 4, and the same warp end is swung back by
the drawing-in gripper 9 into the specified transfer
position, where the drawing-in gripper 9' ~akes over said
warp end, while the transfer gripper 8' during the
transfer operation functions as 10cating aid by pressing
against the warp. The drawing gripper 9' then tensions
the warp end, whereupon the lathe 10' is again beaten
up. Then the adjacent partial shed is formed in the
auxiliary warp half lS', the next warp is moved to the
transfer position by the transfer gripper 8' ant
inserted by ~he drawing-in gripper 9 into the now outer
partial shed as can be seen from Fig. S, whereupon the
warp is again beaten up by the lathe 10'.
Since during these operations the central wire 16
does not participate in the change of sheds, the warp
ends also do no~ wind around it. This is represented
in Fig. 6 by the threads or wires a and b. Subsequently,
the above-described s~eps are repeated in the same order
with the following wires or threads c and d, but this
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1 time the central wire 16 does participate in the change
of sheds and thus is includedin the warp loop. Therefore,
only every other warp of each cloth end forms a load-
bearing warp wire loop 33, 33' capable of transferring
longitudinal forces.
Subsequently, the corresponding operations are repeated
with the other half 15 of the auxiliary warp strip,
wherein this time beating-up is performed by the lathe
10 and the wires or threads e, f and 9, h are inserted
as illustrated in Fig. 6. The structure of the two
lathes 10, 10' is per se known and will not be
explained in detail.
Instead of a single central wire 16 it is also possible
to interweave a plurality of insertion wires disposed
in parallel side-by-side relationship, for instance two
insertion wires 27, 27' as illustrated in Fig. 7,
whereby the strength of the seam is improved due to the
fact that - in contrast to the seam illustrated in
Fig. 6 - all of the warps of the cloth participate in
load bearing. The use of two inserted wires especially
takes into account the fact that with a frequently used
rour-shaft cloth or double-weave cloth, as it is called,
the loops are alternatingly long and short because of
the natural crimp of the thread, as illustrated schemati-
cally in Fig. 7 for a plain cloth. In this case the two
cloth ends 15, 15' are offset relative to each other in
such a way that a respective long loop 28 of the left-
hand wire cloth edge is passed about both inserted wires
27, 27' combined with a short loop 29' of the right-hand
wire cloth edge passed about the right-hand inserted
wire 27', and a short loop 29 of the left-hand wire cloth
edge passed about the left-hand inserted wire 27 is
combined with a long loop 28' of the right-hand wire cloth
edge which is passed about both inserted wires 27, 27'.
1 3 1 8830
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1 In order to fully obtain the advantage of complete seam
strength in another way, a modification of the method
provides that the warp ends after unravelling of the
right-hand and left-hand cloth sides and their
stringing in the magazining hank are respectively
individually interwoven with a loop 34 of a wire helix
25, each warp end being tied up in th~ helix as
illustrated in Fig. 8. In this connection it has been
found suitable to guide the wire cloth ends 15, l5'
provided with the interwoven helix 25 in a device 18
illustrated in Fig. 9, said device being supported
in the traveling mechanism 1 of the seaming machineO This
device is particularly necessary when two parallel wire
helices 25, 25' are employed, which are respectively
associated with a respective side of the wire cloth.
These two wire hel.ices are not interconnected. The
left-hand and the right-hand cloth ends are retained in
the device 18 by means of guide rollers 19, 2û in such
a way that lateral displacement or slipping is prevented.
Then, the wire helices are joined externally of the
seaming machine by means of a common inserted wire.
When using a common inserted or central wire, a guiding
device of the type illustrated in Fig. 9 is not
required, because sufficient positional stability is
ensured by the common central wire.
The control system for the above-described seaming
machine is designed in such a way that the machine may
also weave a wire helix 25 of the kind shown in Fig. 8
into only one cloth side. Finally, it is also possible
to interweave the wire helices, which will later be
joined by a common inserted wire when the wire cloth is
made endless, in the cloth ends together with a wire
26 located in said wire helices (Fig. 10).
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-17-
1 An alternative embodiment to Fig. 9, replacing the
guide rollers 19, 20 with a strong, shedable central
wire 21, is shown in Fig. Il. The function of the
guide rollers 19, 20 is performed by the central wire 21
by connecting both wire cloth ends 15, 15' and fixing
their position relative to the seaming machine.
,'`
The seaming m~chine is useful to provide technical
woven cloths, for instance dryer cloths for dehydration
,: lO machines, paper-making machines and board machines of
the most varied composition, in warp and weft direction
(mono- or multifilament in polyester or polyamide) and
single^ or multi-layer structure with insertion-type
seams. Likewise, it is possible to provide base fabrics
for wet felts in single- or multi-layer configuration
with insertion-type seams.
For reasons of affecting the permeab11ity it may
sometimes be of advantage when the auxiliary warps in the
seam region9 i.e. ~he wefts of the original cloth,
consist of a material different from that of the re-
maining wefts of the cloth.
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