Paper cleaning system

Apparatus for cleaning a moving web, such as paper, paper board or cardboard, prior to printing or processing wherein a tacky wiper cloth engages the moving web to collect contaminating particles. The wiper collection surface is renewable and the apparatus firmly holds the wiper in contact with the web yet is releasable during web threading procedures.

CROSS REFERENCE TO CO-PENDING APPLICATION 
This application claims the benefit of U.S. Provisional application Ser. 
No. 60/031,337 filed Nov. 20, 1996. 
BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The invention pertains to moving web cleaning apparatus, particularly 
suitable for cleaning moving paper, paper board and cardboard webs prior 
to printing for removing dust shavings and loose and embedded contaminants 
from substrate surfaces. 
2. Description of the Related Art 
During the manufacture or processing of moving substrate surfaces such as 
webs of paper, paper board, cardboard, fabric and the like, the surface of 
the web will pick up dust, fiber particles, slitter shavings, scrapings, 
and other loose or embedded contaminants. If the webs are to be printed, 
painted or otherwise coated, such surface contaminants will interfere with 
the coating process significantly reducing the printing or coating 
quality, resulting in rejects. Accordingly, it is highly desirable to 
clean the surface of webs prior to subsequent processing, such as 
printing, in order to achieve the highest quality. 
In the past, webs have been cleaned by blasts of air, vacuum, vibration, or 
other processes such as shown in U.S. Pat. Nos. 3,105,256 ; 4,982,469; and 
5,349,714. However, prior web cleaning systems have not achieved the 
efficiency and quality desirable as needed to consistently produce 
excellent printed surfaces, such as used in the packaging art, box making 
and the like wherein printing standards are high. 
The most common web cleaning apparatus utilizes jets of air or vacuum to 
dislodge loose contaminants from the web substrate, but many particles are 
sufficiently embedded in the web as to not be removable by this means. 
It is known to clean surfaces, such as fabric, clothing and the like, by 
using a tacky material, as shown in U.S. Pat. Nos. 2,624,060 and 
2,755,494, and while such tacky cleaning surfaces are capable of 
effectively picking up lint, dust and the like, the efficiency of the 
cleaning device diminishes with usage as the tacky surface becomes covered 
with the loose particles being picked up eventually rendering the tacky 
material incapable of functioning. 
Previously, web cleaning apparatus capable of high speed production has not 
been available for effectively cleaning rapidly moving webs using a wiping 
technique wherein the engagement of the cleaning material with the web 
produces sufficient mechanical action to remove embedded contaminants. 
OBJECTS OF THE INVENTION 
It is an object of the invention to provide a web cleaning system capable 
of efficiently cleaning moving webs of loose and embedded contaminants by 
a mechanical wiping action. 
Another object of the invention is to provide a web cleaning system for 
moving webs wherein loose and embedded contaminants may be effectively 
removed wherein subsequent web printing and coating processes may occur 
producing excellent quality. 
An additional object of the invention is to provide a moving web cleaning 
system which does not smear, stain or scratch the web substrate surface. 
Another object of the invention is to provide a moving web cleaning system 
capable of upgrading low grade web substrate stock to a higher printable 
grade and wherein frequency of maintenance is reduced while the quality of 
the cleaning process is improved over prior systems. 
SUMMARY OF THE INVENTION 
The web cleaning system of the invention employs an elongated frame 
extending across the width of the moving web. The frame includes a support 
for a cotton cloth which has been treated with a resin compound such that 
the cloth is tacky and capable of picking up and retaining contaminants 
present on the web surface by a wiping action. This mechanical wiping 
action produced by the movement of the web and the engagement of the wiper 
cloth with the web surface effectively removes fiber particles, dust, 
slitter thread cuttings, clay coating scabs, calendar scrapings and 
similar contaminants from the web surface. 
As the contaminants are retained by the resin impregnated cloth, the 
effectiveness of the cleaning action will be reduced as the cloth becomes 
"dirtier". In order to maintain the efficiency of the web cleaning system, 
the resin impregnated cloth is in the form of a dispensing roll whereby 
rolling out of the cloth permits a "new" tacky cloth wiper to be presented 
to the web and thereby maintain the efficiency and effectiveness of the 
apparatus even as it picks up contaminants. The quick renewing of the 
tacky cloth permits continued efficiency of the cleaning operation. 
To ensure that the moving web and tacky wiper cloth are effectively 
engaged, the apparatus employs a movable platen for "opening and closing" 
the apparatus and maintaining the web in engagement with the tacky cloth. 
This movement of the apparatus platen simplifies installation of the tacky 
cloth, and also provides a backing for the web when engaged by the wiper 
cloth. 
The web cleaning system of the invention is highly effective due to the 
mechanical engagement of the web and wiper cloth, as compared with air 
blast or vacuum systems for removing contaminants from moving webs, and 
use of the invention permits lower grade substrate to be used in 
situations where, previously, a higher grade paper product was required, 
such as in the printing of food cartons and the like. Carton waste is 
reduced, and fewer cleaning cycles are required as compared to previous 
web cleaning systems.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
With reference to FIG. 1, the web to be cleaned by the apparatus of the 
invention is schematically represented by dotted lines at 10. This web may 
be of paper, paper board, cardboard, fabric, or the like and is passing 
over drive and idle rollers prior to being further processed, for instance 
printed or otherwise coated. The web 10, for instance a paper or paper 
board web which is printed prior to being formed into boxes or cartons, 
will often have dust, fiber particles, slitter shavings, scrapings, and 
other loose or embedded contaminants located upon the web surface, and 
such foreign matter will adversely affect the quality of printing 
operations. The apparatus of the invention, the cleaning apparatus 12, 
removes such contaminants from the web surface, and the cleaning apparatus 
12 is located within the path of movement of the web to clean the web 
prior to printing or coating operations. 
The cleaning apparatus 12 spans the web 10 and includes an upper elongated 
bridge 14 and a lower bridge 16 disposed immediately below the bridge 14. 
A mounting bracket 17 is mounted upon each end of each bridge, and the 
upper bridge 14 includes a rotatable take-up shaft 18 while the left end 
of the bridge 14, FIG. 1, supports a rotatable dispenser shaft 20. In a 
similar manner, the lower bridge 16 includes a take-up shaft 22 at a 
location below the shaft 18, and the bridge 16 also includes a rotatable 
dispenser shaft 24 at its left end. An electric motor 26 drives the 
take-up shaft 18 through transmission 28, and electric motor 30 drives 
take-up shaft 22 through transmission 32. 
As will be appreciated from the drawings, the shaft 18 is mounted within a 
housing 34 attached to bracket 17 while the dispenser shaft 20 of the 
bridge 14 is mounted within housing 36. In a similar manner, the housing 
38 mounted upon the lower bridge 16 encloses the take-up shaft 22 while 
the dispenser shaft 20 is mounted within the housing 40. 
The cleaning apparatus 12 is relatively heavy, and is supported in such a 
manner as to readily align the cleaning apparatus to the position of the 
web 10. Accordingly, the housings 34 and 38 support a centrally located 
journal 42, while the housings 36 and 40 support a second journal 44. The 
journals 42 and 44 may be mounted in acceptable bearing support structure, 
not shown, in order to position the cleaning apparatus 12 in a proper 
angular relationship to the web 10. 
The upper bridge 14 supports a relatively flat platen 46 on its underside 
while a platen 48 is mounted upon the upper side of the lower bridge 16, 
the platens extending the length of the associated bridge. Hydraulic or 
air expansible chamber cylinders or motors 50 are disposed along the edges 
of the bridges 14 and 16 to support the platens 46 and 48 and permit the 
platens to be moved toward each other, or retracted away from each other, 
the operation of the cylinders 50 being described below. 
Tack cloth guide rollers 52 are mounted upon the bridge brackets 17, FIG. 
2, each having an axis parallel to the direction of movement of the web 
10, and the tack cloth passes around the rollers 52 as later described. 
A roll of tack cloth indicated at 54 is mounted upon each of the dispenser 
shafts 20 and 24, FIG. 1. The tack cloth wound in the form of the roll 54 
is preferably of a milled and woven 4-ply cotton that has been treated 
with a non-static, non-toxic resin compound. The resin compound is of a 
tacky character to which dust, fiber particles, shavings, scrapings and 
the like as may be encountered upon the surface of the web 10 will adhere. 
In operation, the cleaning apparatus 12 will be oriented to the web 10 by 
pivoting of the cleaning apparatus on the journals 42 and 44 such that the 
platens 46 and 48 will be parallel to the web 10, and located upon 
opposite sides of the web. Initially, the cylinders 50 will be retracted 
wherein the platens 46 and 48 will be separated to the maximum extent and 
the web 10 may readily be fed between the platens. 
The tack cloth being dispensed from the rollers 54 is located immediately 
adjacent the associated platen, i.e. the tack cloth on the roller 54 
mounted upon the dispenser shaft 20 will be disposed immediately adjacent 
the upper platen 46, while the tack cloth roller 54 mounted upon the 
dispenser shaft 24 will be immediately adjacent the roller platen 48. The 
tack cloth dispensed from the rolls 54 passes around the guide rollers 52, 
and the upper tack cloth roller free end will be attached to the take-up 
shaft 18 while the lower tack cloth roller free end will be affixed to the 
take-up shaft 22 of the lower bridge 16. 
The cleaning apparatus 12 disclosed in FIGS. 1-4 is designed to clean both 
sides of a moving web or substrate. Accordingly, as the web 10 moves 
through the cleaning apparatus 12, the web 10 will be engaged by the tack 
cloth adjacent both the platens 46 and 48 and the web surfaces will be 
wiped by the tack cloth. During the cleaning operation, the cylinders 50 
will be actuated to move the platens 46 and 48 to their "closed" position 
wherein the platens will be located at their pre-adjusted minimal 
dimensional separation wherein the tack cloth will engage the web 
surfaces, but will not be sufficiently pressed against the web surfaces as 
to interfere with the movement of the web 10 through the apparatus 12. 
Accordingly, dust, fiber particles, shavings, scrapings and other 
contaminants located upon the web surfaces will be engaged by the tack 
cloth and will adhere to the tack cloth ensuring a clean web surface as 
the web surfaces leave the cleaning apparatus 12. This mechanical wiping 
of the web surfaces by the tack cloth is highly efficient in removing the 
type of particles normally found on a web 10 during manufacturing 
processes and a web surface cleaned by the apparatus of the invention is 
capable of receiving and retaining high quality printing and printed 
covering. 
During the cleaning operation, the contaminants will adhere to the tack 
cloth engaging the web surfaces, and eventually, the contaminants will 
accumulate to an extent wherein the cleaning ability of the tack cloth 
will begin to become less effective. At such time, the movement of the web 
10 is terminated, the cylinders 50 may be actuated to retract the platens 
46 and 48 from each other, the motors 26 and 30 will be energized to 
rotate the shafts 18 and 22 winding up the "dirty" tack cloth upon the 
associated shafts and locating clean tack cloth dispensed from the rollers 
54 adjacent the platens 46 and 48. The cylinders 50 may then be actuated 
to "close" the platens 46 and 48, the web 10 again begins to move and 
cleaning thereof occurs with the "new" tack cloth engaging the web. 
The above procedure wherein the movement of the web 10 is terminated during 
renewal of the tack cloth is preferable, but in many installations it is 
not practical to stop the movement of the web 10, and in such instance, it 
is possible to quickly retract the platens 46 and 48, position a clean 
tack cloth adjacent the platens due to the rotation of the shafts 18 and 
22, and close the platens. While such a procedure will permit a portion of 
the web 10 to pass through the cleaning apparatus 12 which has not been 
cleaned, the length of such portion will be relatively small, and the lack 
of cleaning of a small portion of the web is offset by the efficiencies of 
maintaining the web movement. 
It is also possible to position a new tack cloth between the platens 46 and 
48 by merely rotating the take-up shafts 18 and 22 during the normal 
cleaning operation. This procedure can be accomplished during movement of 
the web 10, and is permissible and desirable in some instances. However, 
if the friction between the tack cloth and the web 10 is sufficiently 
great, such lateral movement imposed on the web by the tack cloth movement 
may tend to displace the web 10 laterally in the cleaning apparatus 12. 
However, such lateral forces could be counteracted by rearranging the 
position of the shafts 18 and 22 wherein they are located at opposite ends 
of the cleaning apparatus whereby the tack cloth associated with the upper 
platen moves in the opposite direction than the tack cloth mounted within 
the lower platen. 
In some instances, it is desirable to only clean one side of a web, for 
instance, the outer side of a paper web wherein cartons are to be 
manufactured of the web and only the outer side of the carton is to be 
printed and is desired to be free of contaminants. In such a situation, a 
single side of a web can be cleaned by apparatus such as shown in FIGS. 5 
and 6. 
The apparatus of FIGS. 5 and 6 is substantially identical to the upper 
bridge 14 of the previously described embodiment, and in the embodiment of 
FIGS. 5 and 6, components identical to those previously described are 
indicated by primes. 
The cleaning apparatus 56 of FIGS. 5 and 6 is mounted upon web conveying 
and processing machinery wherein the bridge 14' and associated platen 46' 
will be located directly above the web surface to be cleaned. A flat 
surface, not shown, defined upon the web handling machinery will be 
located directly below the bridge 14' and platen 46' serving as a backing 
for the web as the upper side thereof is engaged by the tack cloth being 
dispensed from tack cloth reel 54'. 
The operation of the embodiment of FIGS. 5 and 6 is identical to that 
previously described, and it will be appreciated that the apparatus of 
FIGS. 5 and 6 is capable of operating at the same high efficiency as the 
previously described embodiment wherein both sides of a web are cleaned. 
It is appreciated that various modifications to the inventive concepts may 
be apparent to those skilled in the art without departing from the spirit 
and scope of the invention.