CA1298732C - Printing press - Google Patents

Abstract

ABSTRACT
A method and apparatus for the automatic production of business forms, wallpaper, newspapers or the like from a web of continuous printing material comprises a printing station including an endless movable printing device such as a rotating cylinder. An image is pro-jetted to a surface of the device. The image is trans-ferred to the web of continuous material at the printing station. Immediately after the printing station, the image is erased from the device so that a remaining por-tion of the image may be projected onto its surface. In this manner the device appears to provide a printing surface of indeterminate length and so is designed with-out relation to the image to be projected. A plurality of such printing stations may be arranged in series for color printing. Furthermore, the operation of the printing station and associated activities may be con-trolled by a pre-selected computer program.

Description

129~37;~:

PRINTING PRESS

Thls invention relates to a method and apparatus for automatically printing a web of paper in the production of business forms, or any form of printing that can adapt to this system, such a~ but not limited to, newspapers or publications with the copy transmitted nationwide from a central location, or as another example production of wallpaper from rolls with infinitely variable patterns.
In the art of manufacturing continuous, multi-part business form~, and in the printing press art in general, a major shortcoming is that the size of the print pattern is limited to the ~lze, l.e., the diameter, of the printing cylinder.
As a re~ult, printing cylinders mu~t be changed ofton in order to accommodate various lengths or repoat# ln the deslred work product.
According to one exomplary embodiment of thi~ lnvention, the printlng cylinder has an lndetormlnat~ length ln the sense that it is able to print at any desired length or pattern repeat wlthout the neces~lty of changing cylinders. In thi~ respect, the cylinder surface may be regarded a~ a con~tantly moving surace, miles long, rather than any fixed size. This i~ because an ionized beam is pro~ected onto the cylinder to create an image thereon which is transferred to a continuously moving web. As the cylinder revolves past the printing position, tho image is erased and another ~ lmage is formed, 80 as to present a constantly : ;
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changing image to the web for continuou~ printing independent of cylinder size.
More specifically, the drum or print cylinder i8 provided with an image receiving photoconductor surface which is rotated past a charging or projection station where laser beams are utilized to project images on the cylinder surface. This is accomplished using laser printing technology such as that disclosed in U.S. Patent No.
3,836,917. The cylinder i~ then rotated to a development station where a powder or toner i8 ~electively deposited on only the charged image areas. When a plurality of colors are used for a particular business forms application, as many as four or more cylinders are employed, each applying a single color.
After the image is transferred to the web, the sheot or web ie passed through heating and chlllinq sectlons to fix the toner or powder on the web.
Meanwhile, immediately after the images from tho respective cylinders are transferred onto tho web, the lmages are erased, again with the aid of laser beams which discharqe the photoconductive surface~ of the respective cylinders.
Upon passing through the various printing statlon~, the web i~ fed through a standard punch ring to an image ~canner. At this station, tho printed image may be reproduced, again with the aid of laser beams, and converted to digital form and ~tored in the computer. Conventional eedback tochnlques are then employed to correct and/or improve specific area~ of the form, or to make minor 129873~

changes in the form format.
The web thereafter passes through laser operated punch heads and cross-perforation device~
and i8 sub~equently wound on a rewind roll.
It i8 to be understood that computer technology is employed to program the press to produce the desired printing, color application and 80 on at each of the printing stations. In a preferred embodiment, controls to the press as well as printing information are included in diskette or cassette form.
The press as described hereinabove has several attendant advantages. The overall weight of the press is substantially reduced, alleviating problems of read~ustment and realignment due to di~tortlon of heavy frame members and compression of floor contours.
Tho press as described hereinabove will en~oy reduced power consumption since large motors (o.g., 7.5 hp) are utilized only to draw the paper through the pres~, with smaller additional motors (adding perhaps another 4 or 5 hp) used in the individual subsystems. This is to be compared with conventional prior art printing presses which normally use ln excess of 50-60 hp.
Tho pross according to an exemplary embodimont o thi~ invontion eliminates the use of convontional negative~ and plates, along with the necessary chemicals. The computerization of all controls also eliminates the neod for numbering machinos and problom~ associatod therewith.
The immodiato drying of the ink at the respective printing stations eliminates the , lZ9873~

necessity of conventional infrared and ultraviolet dryers.
Conventional makeready procedures are also radically altered. With the press according to this invention, the operator need only install a fresh roll of paper in the press, remove the finished roll, and select the appropriate program for manufacturing a form of the desired size and format.
It is further contemplated that even the loading and unloading of the paper rolls themselves may be automated to even further reduce the already minimized manual labor associated with press operation.

SUMMARY OF THE INVENTION
Various aspects of this invention are as follows:
A method of printing a web of continuous printing material on a printing press comprising the steps of:
(a) feeding the web of continuous printing material from a supply roll to a printing station;
(b) projecting at least a portion of an image to be printed on an endless moving printing device;
(c) transferring the image on said endless moving printing device to the web of continuous printing material at said printing station as the web and the image on said endless moving printing device move past each other:
(d) erasing the image from said endless moving printing device immediately after said printing station;
(e) projecting the remaining portion of the image to be printed on said endless moving printing device as it continuous to move; and 1298~73~:
4a (f) repeating steps (c), (d) and (e) to continuously print on the web of continuous printing material until a complete image is printed.
A method of printing a web of continuous printing material on a printing press comprising the steps of:
(a) moving a web of continuous printing material from a supply roll to a printing station;
(b) projecting constantly changing images onto the peripheral surface of a printing cylinder having a predetermined diameter;
(c) transferring the constantly changing images onto the moving web of continuous printing material as it engages the peripheral surface of said printing cylinder, wherein the length of the image applied to the web is independent of the diameter of said printing cylinder; and (d) erasing the images from said printing cylinder immediately after step (c).
A printing press for continuously printing a web of continuous printing material comprising:
(a) feeder means for feeding the web of continuous printing material from a supply roll to a printing station;
(b) an endless movable printing device;
(c) drive means for driving said endless movable printing device past the printing station;
(d) projection means for projecting at least a portion of an image to be printed on said endless movable printing device;
(e) transfer means for transferring the image on said endless movable printing device to the web of continuous printing material at said printing station as the web and the image on said endless movable printing device move past each other;

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4b (f) erase means for erasing the image from said endless movable printing device immediately after said printing station, said projection means, transfer means and erase means thereafter projecting, transferring and erasing the remaining portion of the image to be printed as said endless movable printing device and the web of continuous printing material continue to move past said printing station to thereby print a complete image on the web of continuous printing material.
Other objects and advantages of the invention will become apparent from the detailed description which follows:

BRIEF DESCRIPTION OF THE DR~WINGS

FIGURE 1 is a schematic side view of a business forms printing press in accordance with an exemplary embodiment of the invention;
FIGURE 2 is a schematic plan view of the press illustrated in FIGURE 1;
FIGURE 3 is a schematic diagram of a central control unit for the printing press illustrated in FIGURES 1 and 2;
FIGURE 4 is a schematic side view of a printing station in accordance with this invention; and FIGURE 5 is a schematic side view of an alternative embodiment of a printing station in accordance with this invention.

DETAILED DESCRIPTION OF THE INVENTION

Referring now to FIGURES 1 and 2, the business forms press of this invention generally includes an infeed supply station 10 for a web W, one or more printing stations 12, a line hole punch ring station 14, an image scanning station 16, a laser slitter station 18, a laser punch station 20, a laser cro~s perforation station 22, additional detectors 24 and a rewind station 26.
The infeed station 10 includes a conventional paper supply roll 30, provided with web guides 32 and feed rollers 34. In accordance with this invention, at least one laser detector 36 is provided for monitoring web thickne~s. While large variations in thicknese are not normally found within a single paper roll, the second or third roll ueed in a proce~s may, in fact, contain thickness variatione large enough to create stretch problems in the web. me laser detector serves to alert the preee operator of variations beyond a predetermined acceptable mlnimum ~o that the problem may be corrected. Detectors using laser radiation for meaeuring web thickneee are not new per se. See, for example, U.S. Patent No. 4,322,971 for a representative example of the type of detector which can be utilized in this invention.
A pair of compensator rolls 38 are employed in order to indicate slack and uneven feed of paper from tho supply roll 30. These rolls are operatively connected with the central computer lZ~873~:

control unit 52 which ad~ust~ the ineed roll~ 34 as required.
The printing station 12 includes a unique, indeterminate length printing cylinder 40 which, as earlier stated, enables printing to any desired length or repeat.
In the present invention, each printing cylinder 40 (there may be as many as four or more arranged in series) is preferably constructed of aluminum and coated with a quitable photoconductive surface for receiving an image from an image projector 42. The projector 42 utilizes lasers to project an image onto the photosensitive recording medium applied on the drum surface. In this regard, it i8 to be appreciated that tho drum or cylinder at each printing station should be mounted for easy installation and removal 80 that the cylinder may be removed periodically for rocoating.
In a manner understood by those in the art of laser technology, the printing stations will recoivo, for oxamplo, alpha and numeric character data in olectronic form from the main computer control unit 52, as will be described further hereinbelow, and, in response to such data, print the de~ired characters on the moving web W. Each printing ~tation 12 may have its own light motor drivo M and it~ own computer (not shown). This computer could have its own program to control spacing and tonsion of the web in that particular station, but would, of courso, interface with the main computer control 52.
Aftor the imago is pro~ected onto the lZ~873Z

surface of the cylinder, a toner in the form of powder i~ applied at 44. The powder should be extremely fine grained co that when it i~ picked up by the surface, there is no waste or extraneous material thereon.
After the characters have been applied to the web W as the drum surface rotate~ into engagement therewith, the powder is fused and chilled at 48, 50, respectively (~ee FIGURE 4).
Fusing temperature~ should be greater than 300 F.
A~ the drum continues to revolve, the image is erased by an ionized image eraser 46. Here again, lasers are utilized to discharge the photoconductive surface of the printing drums or cylinders. Normally, tho individual drums would be ccannod to a reguired length, e.g., 24" on a 28"
drum, and as the cylinder revolves past the printing point and the image is erased, a new or continuing image i~ pro~ected on the cylinder. In this way, no open non-printlng gap~ are created.
It i~ to bo understood that the size of the cyllnder i~ not restricted to 28", but may be 22" or 26" or whatever size is most practical for the ~ob at hand. In this regard, because of the effectlve lnfinite length of the cylinder, lt ic po~8ible to print our (or more) 11" images and create a four-part form on a single sheet length of the continuous ~v~b.
Conventlonal prlnting presso~, and even those with newer laser printer~ are unable to create ~uch four-part form~.
The control and sequencing of the image~
to be pro~ected on the drum wlll be di~cussed urther hereinbelow.

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As earlier stated, the la~er drum printing station 12 described above is one of a~ many as four such stations, arranged in series along the path of travel of the web W, each one applying a different one of four primary colors. Obviously, the type and style of form will dictate the number of colors, and hence the number of stations required.
It will be understood that the press may be programmed to have the printing stations print in any given sequence, by color, 80 that, for example, the fir~t station would print black; the second, red; the third, blue; and the fourth, green.
After exiting the printing stations, the web W passes through a conventional line hole punch ring station 14 and below an image ~canner 16, and thereafter through a laser slitter 18, laser punch head 20 and laser cross perforation cutter 22. The ~lze, locatlon, ~pacing, and BO on of the various holes and ellts 18 governed by the use of pre-programmed information on dlskettes or ca~sette~, ln~ertable in the main control unit as doecrlbed further hereln.
The lmage scanner 16 reproduces the printod image and resolves the four color image in a lathe typo mechanlsm, plcks out the colorq and soparatee them by dlgltlllzing, and produces our separato nogatlvos, ono for oach color. Rather than producing a nogative, this information could be conveyod directly to tho printing stations of the prese, particularly to correct and/or improve the work product, or transmitted by computer link to a remote press or presses.
After passing between detectors 24, which lZ98~73'~

insure proper alignment and tautne~ of the paper web W, the paper is rewound at a stand 26.
As is apparent from FIGURE 2, the various components of the press are connected via cable 32 to the main central computer proce~ing unit 52 which is described hereinbelow in more detail in association with FIGURE 3.
In FIGURE 3 there is illustrated a schematic diagram of the various components utilized to control the press of this invention. A form3 composer with full color graphic~, shown at 60, and a matrix color printer 62 for form~ proof~ are utilized in con~unction with a proces~or 64 and color scanner 66 to provide the central processor 52 with the necessary information regarding the four color compo~ition of the forms. A console 68 i~
provldod for in~erting the various cassettes or dlskettos for controlling each of the stations of the pre~, through tho main computor control 52.
When tho ~ob is finished, the diskette 18 ~tored for a repeat order, and is ready to set tho pre~ for an oxact ropeat, or the disketto can be altored with new or deleted copy, without the necos~ity for rosetting the total ~ob, or reworking the pre~ memory diskotte sec~ion when needed.
Turning to EIGURE 4, there is shown a clo~o-up whematic of a laser printing station similar to that lllustrated ln FIGURE 1 but wherein the wob W pa~e~ below a drum 40. As the drum rotates in a counterclockwise direction,tho image is pro~ected onto tho photosensitive surface of the drum at 42 and powder is applied at 44. After the image is transferred to the web W, the powder is lZ9873;~

fu~ed at 48 and chilled at 50, while immediately thereafter, the image on the drum i~ erased at 46.
In its broader a~pect~, the invention relates to the production of busine~ forms by a process which includes the steps of (a) feeding a web from a supply roll to a printing ~tation including at lea~t one rotary printing cylinder; (b) pro~ecting an image on the cylinder as ~aid cylinder rotates; (c) applying toner to the cylinder; (d) transferring the image to the web a~ the cylinder rotatee into engagement with the web; (e) era~ing the image from the drum immediately after the drum di~engages from the web; and (f) projecting a new image on the cylinder as the cylinder continues to rotate.
While the prosently preferred process 18 carriod out with prlnting stations utilizing laser prlntlng technology, lt will be under~tood by those ~kllled ln the art that an ink ~ot type printer may also bo employed. In FIGURE 5, a web W is lllu~tratod pas~ing ovsr and in contact with a drum 70 wlth an ad~acent ink ~et module 72 arranged to e~oct droplete of wrltlng fluid or ink onto the web W ln accordance with a selected computer program cho~on to produco a particular business form.
Tho proeont lnvention has been described particularly ln the context of printing business form~ per se. It i8 contemplated that the computerizod process of this invention may further bo utillzed to produce bar codlng on the forms in a slmple and officiont mannor. It will be further appreciated that tho indetorminate length cylinder as disclosed heroin may also be advantageously 1~9873~

employed in the production of other web-oriented proce~se~, for example, in the publi~hing field, and in the printing o wallpaper. In the production of the latter, a customized product could be produced with a continuou~ly varying pattern, i.e., at no point in a room need there be a pattern repeat.
It will be apparent that many additional changes and alterations may be made in the present invention without departing from the spirit and scope of the claims which follow.

Claims (29)

1. A method of printing a web of continuous printing material on a printing press comprising the steps of:
(a) feeding the web of continuous printing material from a supply roll to a printing station;
(b) projecting at least a portion of an image to be printed on an endless moving printing device;
(c) transferring the image on said endless moving printing device to the web of continuous printing material at said printing station as the web and the image on said endless moving printing device move past each other;
(d) erasing the image from said endless mov-ing printing device immediately after said printing station;
(e) projecting the remaining portion of the image to be printed on said endless moving printing device as it continues to move: and (f) repeating steps (c), (d) and (e) to con-tinuously print on the web of continuous printing mate-rial until a complete image is printed.

2. A method as defined in claim 1 further com-prising the steps of scanning the image transferred to the web for variations from a predetermined image design and compensating for such variations.

3. A method as defined in claim 1 wherein steps (a) through (f) are carried out at a plurality of print-ing stations, each printing station for printing in a different color.

4. A method as defined in claim 1 wherein step (b) is carried out utilizing a plurality of lasers.

5. A method as defined in claim 1 wherein said endless moving printing device is a rotary cylinder hav-ing a photoconductive surface.

6. A method as defined in claim 5 wherein said projecting step projects a charged image on the photoconductive surface of said rotary cylinder, and wherein the method further comprises the step of apply-ing toner to the charged image on the photoconductive surface of said rotary cylinder, and said transferring step transfers toner to the web of continuous printing material in accordance with the charged image.

7. A method as defined in claim 6 further com-prising the step of fixing the toner image on the web of continuous printing material.

8. A method as defined in claim 1 wherein said projecting step projects a constantly changing image.

9. A method as defined in claim 1 wherein said projecting step projects a succession of different images.

10. A method as defined in claim 9 wherein said transferring step successively transfers the succession of different images on said endless moving printing device to the web of continuous printing material and said erasing step erases the succession of different images from said endless moving printing device immedi-ately after said printing station.

11. A method as defined in claim 1 further com-prising the step of monitoring the thickness of the web prior to step (b).

12, A method as defined in claim 1 further com-prising the steps of slitting or perforating the web in predetermined locations, and rewinding the web.

13. A method as defined in claim 1 wherein steps (a) through (f) are controlled by a pre-selected com-puter program.

14. A method as defined in claim 1 further com-prising the step of repeating steps (a) through (f) to continuously print a series of complete images.

15. A method of printing a web of continuous printing material on a printing press comprising the steps of:
(a) moving a web of continuous printing mate-rial from a supply roll to a printing station (b) projecting constantly changing images onto the peripheral surface of a printing cylinder hav-ing a predetermined diameter;
(c) transferring the constantly changing images onto the moving web of continuous printing mate-rial as it engages the peripheral surface of said print-ing cylinder, wherein the length of the image applied to the web is independent of the diameter of said printing cylinder; and (d) erasing the images from said printing cylinder immediately after step (c).

16. A method as defined in claim 15 further com-prising the step of repeating steps (a) through (d) until a complete image to be printed is transferred to the web of continuous printing material.

17. A method as defined in claim 16 wherein the image to be printed is a business form and the con-stantly changing image is formed by at least alpha and numeric character data, the amount of alpha and numeric character data transferred to the web by said transfer-ring step being independent of the diameter of said printing cylinder.

18. A method as defined in claim 15 wherein steps (a) through (d) are carried out in accordance with a pre-selected computer program.

19. A method as defined in claim 15 wherein steps (a) through (d) are carried out at a plurality of printing stations, each station for printing in a dif-ferent color.

20. A printing press for continuously printing a web of continuous printing material comprising:
(a) feeder means for feeding the web of con-tinuous printing material from a supply roll to a print-ing station (b) an endless movable printing device;
(c) drive means for driving said endless mov-able printing device past the printing station;
(d) projection means for projecting at least a portion of an image to be printed on said endless mov-able printing device;
(e) transfer means for transferrinq the image on said endless movable printing device to the web of continuous printing material at said printing station as the web and the image on said endless movable printing device move past each other;
(f) erase means for erasing the image from said endless movable printing device immediately after said printing station, said projection means, transfer means and erase means thereafter projecting, transfer-ring and erasing the remaining portion of the image to be printed as said endless movable printing device and the web of continuous printing material continue to move past said printing station to thereby print a complete image on the web of continuous printing material.

21. A printing press as defined in claim 20 wherein said projection means, transfer means and erase means respectively project, transfer and erase a succes-sion of images to be printed.

22. A printing press as defined in claim 21 wherein the succession of images to be printed are busi-ness forms formed by at least alpha and numeric charac-ter data, the amount of alpha and numeric character data in each image being transferred to the web by said transfer means being independent of the length of said endless movable printing device.

23. A printing device according to claim 20 wherein said projection means projects a constantly changing image.

24. A printing device according to claim 20 wherein said projection means, transfer means and erase means operate in response to a pre-selected computer program.

25. A printing device according to claim 20 wherein said endless movable printing device is a rotary cylinder having a photoconductive surface, said projec-tion means charges the photoconductive surface with a charged image corresponding to the image to be printed, and said transfer means includes toner means for apply-ing toner to the charged image on the photoconductive surface and transferring the toner to the web of contin-uous printing material to print the image as said rotary cylinder and the web move past each other, said printing device further comprising fixing means for fixing the toner on the web of continuous printing material and said erase means comprising dis-charge means for discharging the photoconductive surface of said rotary cylinder.

26. A printing press as defined in claim 20 wherein said projection means includes a plurality of lasers at each of a plurality of printing stations.

27. A printing press as defined in claim 20 fur-ther comprising forming means for slitting or perforat-ing the web of continuous printing material.

28. A printing press as defined in claim 20 fur-ther comprising scanning means for scanning the image transferred to the web for variations from a predetermined image design and compensating means cou-pled to said scanning means for compensating for the variations.

29. A printing press as defined in claim 20 fur-ther comprising a plurality of printing stations, each printing station for printing in a different color.