CA1293366C - Paper-making wire repair kit - Google Patents

Abstract

ABSTRACT OF THE DISCLOSURE
Paper-making, pulp-dewatering wires or webs are now made of a woven fabric of synthetic resin filaments. Such a fabric is often accidentally perforated. A patch of similar fabric is placed on the perforation and secured to the wire by means of a series of staples. The patch is circular and the legs of the staples are radially directed. The patch is positioned on the paper-contacting face of the wire and the bight of the staples does not protrude from the underside of the wire. An apparatus is disclosed for the insertion of the staples through the wire and the patch.

Description

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F I E LD OF l'HE _ I NV}J NT I ON
The present invention relates to a paper-making wire repair kit and, more particularly, to a patch assembly for patching perforations accidentally made in a paper-making wire or pulp-dewatering fabric, and to an apparatus for fixing the patch of the fabric.
9~QOF THE INVENTION
Paper-making wires used for pulp-dewatering nowadays consist of a woven fabric of fibres of synthetlc resin. Such ~10 wires are liable to become accidentally perforated during use. A
perforated fabric causes defects in the paper made therewith and must be replaced or repaired. Such wires are very expensive, since in a paper-making machine, it is not uncommon to find wires of 90 feet long and between 150 and 140 inches wide, and costing 520,000,00 ~and more. It has ~been tried--but without good results--to fix a patch onto the perforation of such a ~wire by means of an adhesive or glue, ;It has been found that the patch ~falls away very qu~ickly with use.
OB~iSC rs - OF THi INVENTION ~ ~
~ It ls the general ob~ect of the present invention to IX a~ patch on~ a paper-making wire in such a way that the patch w~ remain attached to~the wire for a long time during use of the w~ire.~
Another ob~ect of the present invention is to provide a patch and~the ueans to ix the patch to the wire, so arranged ;that~they only slightly protrude from the pulp-contacting face of ~L293~6 the wire, so as to produce paper without any defect which could be caused by the patch, or the means to attach the same to the wire.
Another object of the present invention is to provide an apparatus for fixing a patch to a paper-making wire, which is of simple construction and easy to operate.
SUMMA~Y OF THE _ VENTION
In accordance with the invention, there is provided the combination of a paper-making, pulp-dewatering wire having a perforation with a patch covering the perforation, the patch being applied against the pulp-contacting face of the wire and covering the perforation and an adjacent portion of the wire around the perfora~ion, and metallic U-shaped staples e~tending through the wire and the patch, with the legs bent against said patch, and the staples disposed around the perforation.
Preferably, the patch is of circular shape and the staples disposed in a circle around the perforation, with the legs of the staples outwardly bent and oriented radially of the patch. The : ` ~
blght of the staple preferably does not protrude from the underface of the wire.
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~ Ihe apparatus to fix the patch to the wire by means of :
the staples, comprises a base plate provided with a plurality of ~staple-ejecting plungers, a pusher plate disposed over the base plate and having a wire-contacting face and through-bores slidably receiving the plungers; biasing means to move the pusher plate from a retracted to an advanced position, spaced from said :

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base plate, stop means to stop said pusher plate at said advanced position under the bias of said biasing means; and guide means to guide the base plate during its movement between said retracted and advanced position, and wherein the stroke of said pusher plate from its retracted to its advanced posltion is at least equal to the length of a staple, such that in said advanced position, a staple inserted in a through-bore and contacting the plunger therein, does not protrude from said wire-contacting face of the pusher platel and in its retracted position, the end of said plunger is at least flush with said wire-contactlng face.
Preferably, the through-bores have a cross-sectional elongated shape, conforming to the cross-section of a U-shaped staple to ~positively orient the latter ln the through-bores. Preferably, a soft pad is arranged to be applied on the patch opposite the ;~ pusher plate to press the latter to its retracted position while ~;compressing the patch on the wire, causing e~ection of the staples and;insertion of their legs through said wire and patch ~and lnto said pad, thereby causing compression.of the~wire by the bight of the~staples. ~The legs of the wire are bent outwardly~by means of suitable tools, B~IE DE5 PIPI'ION OP l'HE VRAWING5 Figure 1~ is~. an exploded,~ partlal perspective view showi~ng the paper-making ~ire having a perforation, a patch to cover said perforati~on~and~the apparatus for~ flxing the patch to the~wire by~méans of staples;
Flgure 2 is a ~top plan view of the arrangement of ~:
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1~933~6 Figure 1, but without the overlying rubber pad;
Figure 3 is a cross-section taken along llne 3-3 of Figure 2, with the rubber pad in position, and showing the pusher plate in advanced position;
E'igure 4 is a view similar to that of ~igure 3, on an enlarged scale, and showlng the pusher plate in retracted position, with the staples inserted through the wire and the patch, and into the pad;
Figure 5 shows the tooling to bend the legs of the staples outwardly;
Figure 6 is a partial plan view of the wire and patch in assembled position; and Figure 7 is a partial cross-section, taken along line 7-7 of Figure 6.
In the drayings, like reference numerals indicate lihe : elements throughout, ~ :

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DETAILED DESCRI pTroN ~OF THE PREF RRED rEMBODI~MENT
Referrlng to Figures 1, 2, 6, and 7, there is~ shown a ~:
paper-makiny wire, indicated at 10, of conventional c~on~struction.
Such:wires usually cons:ist of a woven fabric of synthetic resin fibres,;;such as nylon~.~ This wire forms an endless band used in~ :~
F~oudr~in~i~er paper-making machines, in ~ which the :~band: is : ~
hori~ontal,~or used in~newer ~ypes of paper-making machines, such:
as~the twin wires former in which the pulp coming~fr~om~the head box~of the: machine as a water suspension, is~squeezed between the two verticaI runs of the wires, and the pulp is dewatered by exit :
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~9~3~6 of the' water through the interstices of the fabric. Such paper-making machines are made, for instance, by BLACK CLAWSON PAPER
MACHINE DIVISION, of Watertown, New York, under the general trade mark VERTI-FORMA. The face of the wire from which the water exits, that is the face of the wire opposite the pulp-contActlng face, is subjected during travel of the wire to a scraping action effected by stationary blades, called foils, generally made of ceramic.
It frequently happens during paper-making that such wires become perforated due, for instance, to the accidental presence of small metal objects in the head box, or for whatever othsr reason. Such perforatlons produce defects in the paper made therefrom. Attempts have been made to try to patch the - perforations with patches adhering to the wire by meane. of glue or the like. Such patches are soon dislodged during use of the wire.
E'igure 1 shows at 12 a perforation made in the wire or fabric 10. In accordance with the invention, a patch 14 is applied over the perforation 12. l'his patch may have a rectangular or square shape, but with rounded corners, and is preferably of clrcular shape, as shown. This patch is made of a material similar to that o'f fabric 10, but ~preferably of smaller thickness. The patch is of sufficient size to overly the area of .
the fabric 10 surrounding the perforation 12 to receive fasteners dlsposed around the perforation 12.
In accordanc~ wlth the ~nven~lon, such fast-ners ~:

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:lZ933~16 consist of metallic staples 16, each of U-shape, comprising a bight 18 and a palr of legs 20.
l'he wire 10 has a pulp-contacting face 22 and an opposite face 24, against which the foils are adapted to scrape.
The patch 1~ is positioned over the pulp-contacting face 22.
When the patch is assembled by the staples 16, as shown in Figures 6 and 7, the bight 18 o~ each staple engages the opposlte face 24 and the legs extend through the wire 10 and the patch 14, and the legs 20 are outwardly bent and curved with their outer ends dlgging into the fabric of the patch 14, as clearly shown in E`igure 7, Slnce the bight 18 compresses the thickness of the wire 10, it does not protrude from the remaining opposite face 24 and, therefore, the bights 18 will not be affected by the folls of the paper-making machine.
Preferably, the staples 16 are equally, angularly spaced around the patch, as shown in Flgure 6, and their legs, which are outwardly bent, are radially directed. With this arrangement, the patch is firmly held to the wire 10 and the patch and staples will not cause defects in the paper made with ~ ~ 20~ the~patched wire, as has been tested in several experi~ents made -~ in Canada.
Obviously, more than one circular row of staples 16 may be used, wlth all the circles of staples belng generally concentric with the perforation 12.
Figures l to 5 show a pre4erred apparatus for securlng the patch to the wire by means of the staples 16, lrhis apparatus ~:
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~Z~33~6 comprises a circular base plate 26 secured to the underside of a table 28 by means of bolts 30 and straddling an opening 32, made in the table 28. The table is used to support the wire 10 with its perforation 12 over opening 32, the wire being placed on the table with its pulp-contacting face 22 on top.
A plurality of plungers 34 are secured to the base plate 26 and upwardly extend therefrom, A pusher plate 36 is disposed over the base plate 26 and has a plurality of through-bores 38, each slidably receiving a plunger 34. The pusher plate 36 is guided for up-and-down movement by means of guide bolts 40 screwed within the pusher plate 36 and slidably extending through a through-bore made in the base plate 26, with the head 42 of the bolt underneath the latter, The head 42 of the gulde bolts serves as a stop means to limit the upward movement of the pusher : plate to:an advanced position, slightly below the top face of the table 28.
Compression coil springs 44 surround each bolt 40, abut against the underside of the pusher plate 36 and against the : :
shoulder formed:by a countersunk portion of the through-bore for ~the~guide bolts 40, as shown at 46, Thus, the pusher plate 36 ~:;: can take a ret:racted position, as shown in Figure 4, against the bias~of the coil springs 44, and in which the pusher plate abuts ~: ~
against the base plate 26.

The apparat~us further includes a soft pad 48, of a size `
su~Eicient to extend beyond the patch 14. This pad 48 ls made of soft~material, preferabl~y elastomeric material, such as rub~er, ::
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~2~3366 for easy insertion of the legs 20 of the staples 16, without bending of the same In the advanced position of the pusher plate, one inserts a staple in each through-bore 38 of the pusher plate 36, with the bight 18 contacting the end of the plunger 34 and, therefore, with the legs 20 of each staple being upwardly directed.
The stroke of the pusher plate from its retracted to its advanced position is at least equal to the length of each staple 16. Therefore, in the advanced position of the pusher plate, each staple inserted in its throu~h-bore 38 does not protrude from the wire-contacting face 50 of the pusher plate 36, and yet in the retracted position of the pusher plate, the end of the plunger is at least flush with the wire-contacting~face 50, as shown in Figure 4 To operate the apparatus, the wire 10 is placed on the ta~le 28, with the perforation 12 to be patched over the pusher plate. ~ The patch 14 is placed over the perforation 12. Pad 48 is~ placed over the patch 14 and then:pressed downwardly, as shown ~20 ~in F~igure ~9, whereby the assembly of the wire 10 and patch 19 is fo~rced against~face 50 of the;pusher:plate 46, and the latter is pushed down against base~ plate~26 against the bias of the coil~
sprLngs 44, whereby all of the staples 16 are pushed up through the~wlre 10 and pa~tch:~l4, and thelr legs 20 enter the pad 98.
The~assembly~is then shlfted over a recessed portion 52 of table ~28 pro~ided~ with a clrcular ~ridge 54. The circular row of :~ 8 :

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staples 16 is placed in register with ridge 54. A pair of handtools 56, each terminated by a flat blade 58, are used, after removal of pad 48, to press against bight 18 and to individually bend each leg 20 of each s~aple 16 radially outwardly against the patch lq.
Although the through-bores 38 are shown as of rounded cross^sectional shApe, it is preferred to make them of elonga~ed cross-sectional shape, together with the plungers 34, such a shape conforming to the cross-sectional shape of a staple 16, so as to automatically orient the staples, so that their legs 28 would be, without any difficulty, bent radially outwardly along : radial lines of the patch 14.

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Claims (7)

1. An apparatus for use with U-shaped staples of substantially same dimensions and consisting of a bight and of two legs, said apparatus destined to fix a patch onto a face of a paper-making pulp-dewatering wire to cover a perforation of said wire and comprising:
a base plate, a plurality of staple-ejecting plungers fixed to, and upstanding from, said base plate, a pusher plate disposed over said base plate, having a wire-contacting face and having through-bores slidably receiving said plungers, biasing means to move said pusher plate from a retracted to an advanced position, spaced from said base plate, stop means to stop said pusher plate at said advanced position under the bias of said biasing means, and guide means to guide said pusher plate during its movement between said retracted and said advanced position;

wherein the stroke of said pusher plate from its retracted to its advanced position is at least equal to the length of a staple, such that in said advanced position, a staple inserted in a through-bore and contacting the plunger therein, does not protrude from said wire-contacting face of said pusher plate, and in its retracted position, the end of said plunger is at least flush with said wire-contacting face.

2. An apparatus as defined in claim 1, wherein each through-bore has a cross-sectionally-elongated shape conforming to the cross-section of the U-shaped staple to positively orient the latter in said through-bore.

3. An apparatus as defined in claim 1, wherein said through-bores are arranged in a circle in said pusher plate.

4. An apparatus as defined in claim 3, wherein each through-bore has a cross-sectionally-elongated shape conforming to the cross-section of a U-shaped staple to positively orient the latter in said through-bore.

5. An apparatus as defined in claim 4, wherein said through-bores are radially oriented relative to the center of said circle.

6. An apparatus as defined in claim 1, further including a soft pad arranged to be applied onto said patch opposite said pusher plate to press the latter to its retracted position while compressing said patch onto said wire, causing ejection of said staples and insertion of their legs through said patch and wire, and into said pad with said bight engaging under said wire.

7. An apparatus as defined in claim 6, further including tool means to bend said legs over and against said patch.