PROCESSING CONTINUOUS FORM PAPER

Abstract: An attachment to enable an offset press 10, of a type adapted to process individual sheets of paper, to feed and print continuous forms stationery in proper registery includes, in addition to an intermittently operable paper feeding station 14 downstream of the press, a separate registration station 12 upstream of the press. The registration station 12 maintains continuous engagement with the paper 16 by means of a freely rotatable, endless pin belt 66 which engages the pin holes 70 of the paper and individually registers each increment of paper to the press 10 while the paper is disengaged by the paper feeder 14. A rotating disc 80, operatively connected to the pin belt 66, includes a plurality of windows defined by adjacent posts 82 for receiving a solenoid activated, wedge-shaped finger 86 which arrests and positions the disc 80, and hence the paper, in one of a plurality of predetermined positions. A sensor 44 associated with the paper feeder station 14 detects when the paper is engaged or disengaged with the paper feeder and generates a signal to the solenoid 84, but there is no mechanical interconnection between the paper feeder and the registration device. In another embodiment the intermittent paper feeding function may be accomplished solely by the printing blanket of the offset press.

Description: BACKGROUND OF THE INVENTION This invention relates to the feeding and registering of continuous form paper to a processing unit such as for example an offset press and to adapting a processing unit such as an offset press, originally adapted to process single sheets of paper, to process continuous form paper. The arrival of the word processors and high speed, computer controlled printers in modern offices and businesses has created a need for a variety of business documents, such as invoices, purchaser orders, letterhead, envelopes, checks, and the like to be available on continuous form paper so they may be rapidly processed by the high speed office printer. One method of providing such a capability is to mount the business documents such as letterheads or invoices onto continuous carrier paper. This involves several processes, first the business document must be printed and second it must be mounted on the carrier paper precisely aligned and registered so that the high speed office printer, which is referenced to the carrier paper through the pin holes on the margins of the carrier paper, will know where to print and where to not print. Expensive, relatively slow machines are needed to mount the documents on the carrier paper in precise registry. Another method is to print the business documents such as letterhead or invoices directly onto the continuous form paper and then, through the use of perforations in the continuous form paper, separate the printed documents from the marginal strips having the pin holes therein and from the adjacent printed documents. This process is preferable to the carrier mounted method since it eliminates a step and an expensive machine, but it has the same requirement for precise registry. The printing on the continuous form must be precisely placed with respect to the perforations which define the separate documents within the continuous form paper. Lack of proper registration can cause printing to run over the perforations extending across the continuous form paper which define the separate documents. Printing on continuous form paper raises another problem, especially in the case of letterhead which should have an "clean edge" appearance and not display detectable serrations on the edges. While perforation methods and apparatus are available which can achieve such a clean edge appearance when the individual sheets of letterhead are broken out of the continuous form, such clean edge perforations are very delicate and prone to breaking during processing. There is therefore a problem in arranging to feed and precisely register continuous form paper to a press or other processing unit without breaking the perforations, even clean edge perforations. Most of the existing machines for processing continuous form paper use a "tractor feed" device, a system of multiple driven pin wheels or pin belts which engage the pin holes on the margins of the continuous form paper and pull the paper through the processor. Similarly, most of these machines also use the tractor feed mechanism to index or register the continuous form paper to the press or processor. In many processors, such as offset presses and perforators, it is necessary to stop, retard, or advance the passage of paper through the processor to keep the paper in proper registry with the printing or perforating cylinder. Disadvantages associated with this type of system include the fact that each of the tractor feed drives on a particular unit must be synchronized and timed with respect to each other and to the processing unit, and that any imprecision in the feeding system is carried over into the registration system. Thus small errors can, with sufficient iterations, accumulate into large errors. Furthermore, the stopping, starting, retarding and advancing of the multiple tractor feed devices, all of which engage the paper, has a tendency to distort or rip the pin holes, or break the perforations, especially clean edge types of perforations. To some extent, these disadvantages can be avoided by providing an intermittently operable paper feeder arrangement and a separate registration device which can operate to index the continuous forms documents between each feed operation while the paper feeder is disengaged from the paper. Such a system is disclosed in U.S. Patent No. 3373684 of Fisher, but the Fisher arrangement is designed for use with a standard multigraph type printing press having a driven drum carrying a printing plate and the registration device is linked mechanically with a separate paper feeder and with the drive for the printing plate drum. As disclosed, it would not be suitable for use with an offset press of the kind having a printing blanket mounted on a blanket cylinder that is disengageable with an impression cylinder and would not be suitable for use as a readily fitted removable attachment to convert or modify an existing printing press or like processing unit. Moreover, in that the operation of the Fisher registration device is directly dependent upon and is related to the speed of the press drive through the mechanical linkage which in any event is relatively slow acting, it tends to allow the paper to float freely for a significant period during the transitions between successive paper feed and registration indexing operations and the device is not suitable for high speed operation. For indexing, Fisher also proposes the use of a rotating star wheel type detent but this also has disadvantages especially for operation at high speed. Acknowledgement is also made of DE-C-1124582 which discloses apparatus associated with a printing press for discontinuously feeding and registering or indexing continuous paper. However, in this case the means for registering or indexing the continuous paper is an integral part of the paper feeding means, the latter comprising a driven mechanism additional to the printing elements of the press. Summary of the Invention The present invention seeks to provide an improved apparatus for use in registering continuous form paper fed through a processing unit, in particular a printing press, which apparatus, at least in preferred embodiments, can be applied to processing units such as high speed offset printing presses and may be designed as an attachment capable of being readily fitted and removed without substantial effort or modification. More specifically, the present invention as claimed provides a printing press adapted to discontinuously feed continuous form paper and to print said paper at a printing station thereof, said press being provided with: (a) registration means located at a registration station upstream of said printing station, for maintaining the continuous form paper in proper registry; (b) sensing means for detecting each time a predetermined form length of said paper is fed forwards through the press; and (c) electrical control means in operative association with said sensing means and with said registration means, effective to control activation of said registration means and thereby cause the latter to index the continuous form paper and to arrest further movement thereof each time the sensing means detects a feed of a said predetermined form length of the paper, characterised in that (i) the printing press is of the type having a blanket cylinder carrying a printing blanket which co-operates with an opposed impression cylinder to effect printing and also to discontinuously feed the paper through the press, in that (ii) the co-operation between said blanket-carrying blanket cylinder and said opposed impression cylinder provides the sole feed means for feeding the continuous form paper, the circumferential length of the printing blanket being matched to said predetermined form length of the paper and said registration means being operable without any paper moving function other than that of selectively moving the paper backwards or forwards to adjust its position during indexing, and in that (iii) the sensing means is operatively associated with said blanket cylinder. From another aspect, the invention also consists in apparatus used for modifying a printing press to enable or facilitate it to print discontinuously fed continuous form paper at a printing station of the press, said apparatus comprising: (a) registration means for maintaining the continuous form paper in proper registry at a registration station upstream of said printing station; (b) sensing means for detecting each time a predetermined form length of said paper is fed forwards through the press; and (c) electrical control means in operative association with said sensing means and with said registration means, effective to control activation of said registration means and thereby cause the latter to index the continuous form paper and to arrest further movement thereof each time the sensing means detects a feed of a said predetermined form length of the paper, characterised in that (i) said apparatus does not include any paper-feeding means, said registration means being operable without any paper moving function other than that of selectively moving the paper backwards or forwards to adjust its position during indexing, in that (ii) said apparatus forms a removable attachment and is used to reversibly convert a press designed to feed and print only single sheets of paper to a press capable of discontinuously feeding, printing and maintaining in proper registry continuous form paper, said press being of the type having a blanket cylinder carrying a printing blanket which co-operates with an opposed impression cylinder to effect printing and to discontinuously feed paper through the press, the co-operation between said blanket-carrying blanket cylinder and said opposed impression cylinder providing in use the sole paper feeding means, and in that (iii) in use said sensing means is operatively associated with said blanket cylinder. In preferred embodiments, said registration means includes paper engaging means arranged to maintain continuous engagement with the continuous form paper, said paper engaging means being freely movable during feeding of the paper while the registration means is deactivated and being separate and mechanically independent from said blanket cylinder. Also, the registration means includes detent means arranged selectively to interact with said paper engaging means, in response to activation by said electrical control means, through an indexing element thereby to bring about the indexing and arrest of the continuous form paper, said indexing element comprising a rotatably mounted low mass disc-like body operatively connected to said paper engaging means and provided with a ring of circumferentially-spaced projections extending parallel to the rotational axis of said body and defining a series of circumferentially-spaced gaps for engagement with said detent means. The foregoing and other objectives, features, and advantages of the invention will be more readily understood upon consideration of the following detailed description of a preferred embodiment, taken in conjunction with the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS FIGURE 1 is a partially schematic elevational view of an embodiment of the present invention in conjunction with an offset printing press; FIGURE 2 is a plan view of the registration portion of the embodiment of FIGURE 1; FIGURE 3 is an elevational view of the registration portion of said embodiment; FIGURE 4 is an elevational view of the registration portion of the embodiment of FIGURE 1 taken along lines 4-4 of FIGURE 2; FIGURE 5 is a schematic, partial elevational view of a cam and cam follower arrangement associated with the paper feeding portion of the press; FIGURE 6 is a partial view of the infeed portion of the apparatus illustrated in the preceding Figures, showing a vacuum brake and dancer; FIGURE 7 is an elevational view of the dancer taken along lines 7-7 of FIGURE 6. DETAILED DESCRIPTION The apparatus of the present invention shown in the drawings is described herein in conjunction with an offset printing press which is of the type adapted to process individual sheets of paper and which employs a modified printing blanket assembly as a paper feeder. Turning to FIGURE 1, the apparatus of the present invention is shown therein in conjunction with the offset printing press 10 which is adapted to print individual sheets of paper, and it includes a registration station 12 upstream of the press. The press 10 includes a blanket cylinder 18 and a parallel opposed impression cylinder 20 which rotate at the same speed. The blanket cylinder and impression cylinder are arranged so that there is a small space (approximately .033 inch, i.e. 0.84 mm) between them. The blanket cylinder mounts a printing blanket 22 whose thickness (.035 inch, i.e. 0.89 mm) exceeds the space between the cylinders. The printing blanket contains the image to be printed onto the paper. An assembly of ink rollers 24 is provided to spread ink and water which is transferred as usual onto the printing blanket. It should be noted that the blanket cylinder and impression cylinder are arranged and rotated so that when the blanket becomes opposed to the impression cylinder the combined rotation of the two cylinders will pull paper through the press, but when the blanket is not opposed to the impression cylinder, the paper, being thinner, e.g. 0.10mm (.004 inch) than the space between the cylinders, will not be acted upon by the press. Turning now to the registration station 12 of the apparatus shown in FIGURES 1 through 4, with initial reference to FIGURES 2 and 4, an endless pin belt 66 having a plurality of pins 68 thereon is arranged so that a portion of the endless pin belt is co-planar with the paper plane 28 and aligned so as to cooperate with the pin holes 70 along one margin of the continuous form paper 16. A paper guide 72 straddles the pins as they protrude from the paper to ensure that the pins are, and stay, securely seated in the pin holes of the paper. A pair of upper pulleys 74 position the endless pin belt in the paper plane. The pin belt is also trained over a lower pulley 76 which is fixed to an indexing shaft 78. Turning FIGURES 2 and 3, it may be seen that the indexing shaft has a disc 80 attached thereto for rotation therewith. The disc 80 has a plurality of posts 82 mounted at regular intervals around the circumference thereof. The endless pin belt 68, pulleys 74, 76, indexing shaft 78, disc 80 and posts 82 are all preferably made from strong, durable, yet light material so that the mass and therefore the inertia of the registration assembly is minimized. To this end, the disc, preferably nylon, has plurality of holes formed therein. A registration solenoid 84 having a wedge-shaped finger 86 attached to its piston is mounted proximate the disc so that activation of the solenoid causes the wedge-shaped finger to extend within the circumference of the disc contacting the posts and stopping the rotation of the disc. As shown in dashed lines in FIGURE 3, the wedge-shaped finger wedges in between two posts, causing the disc to rotate to a position so that the adjacent posts are equidistant from the axis of the wedge-shaped finger, represented by the arrow 88. A return spring 90, fastened to mounting plate 100 and to the finger, serves to retract the finger from engagement with the disc and the posts when the solenoid is energized. Continuous form paper 16 is fed from an infeed pack through the registration station where it is engaged with the pins of the endless pin belt and through the press, between the blanket cylinder and the impression cylinder. When the apparatus is operated, the paper feeding function is accomplished by the printing blanket 22 and blanket cylinder 18 in cooperation with the opposed impression cylinder 20. The paper 16 is pinched between the rotating blanket and the rotating impression cylinder and drawn through the press at the same time it is being printed by the blanket. As hereinafter described, when the paper is disengaged by the press, a signal is generated which is sent to the registration solenoid to cause the wedge-shaped finger to extend within the circumference of the disc. Similarly, when the paper is again engaged by the press and pinched between the rotating blanket and the rotating impression cylinder, a further signal is generated to de-energize the registration solenoid and the finger 86 will be pulled out of contact with the disc 80 by the spring 90. As may be understood with reference to FIGURE 3, as the wedge-shaped finger 86 protrudes into the rotating disc, the point of the finger will enter into a "window" defined by the adjacent posts 82. As the finger thrusts into complete engagement with the posts, the wedge shape of the finger will cause the disc 80 to rotate, either forward or backward, so that the adjacent posts are equidistant from the axis 88 of the finger. In this way the disc is arrested and positioned in one of a number of predetermined positions, each predetermined position defined as the mid-point of the window between adjacent posts. Since the disc is linked to the endless pin belt which engages the pinholes of the paper, the paper will be positioned in one of a number of predetermined positions. Recall that when the registration solenoid is fired, the blanket has just disengaged from the paper and the paper may be freely moved forward or backward by the disc and pin belt of the registration station. It will be readily understood that one of the advantageous features of the present invention is that reiterative indexing of the continuous form paper with respect to the printing press processing unit after each document is printed prevents cumulative error. It should also be pointed out that the registration is very precise due to the interaction of the wedge-shaped finger and the posts, and that the "window" concept allows for a large margin of error in generating the signal to the registration solenoid. The printing blanket is sized so that its length, arranged on the blanket cylinder, is equal to the predetermined incremental length of the paper to be printed. As explained previously, when the printing blanket 22 rotates out of contact with the paper the paper is disengaged from the press and may be moved with respect to the press by the registration station which operates substantially as explained above. Of course it is necessary to provide timely signals to the registration solenoid 84 when the blanket disengages from the paper, and again when it is about to reengage the paper. With reference to FIGURES 1 and 5, the shaft (not shown) journaling the blanket cylinder is axially tapped and threaded to receive a bolt 110. The bolt is used to fasten a pair of adjacent, concentric, circular plates 112, one plate superimposed upon the other, to the end of the blanket cylinder shaft for rotation therewith. Each plate has a cam 114 formed on the circumference thereof. The plates may be rotated with respect to each other and locked in positional relationship by the bolt so that the circumferential length of their combined cams corresponds angularly with the circumferential length of the printing blanket on the blanket cylinder. As may be seen in FIGURES 1 and 5, the angular displacement of the cams on the circumference of the plates corresponds to the angular displacement of the printing blanket on the circumference of the blanket cylinder. A cam follower 116 operatively connected to a microswitch 118 generates the signal to the registration solenoid 84 to cause it to de-energize and allow the spring 90 to pull the finger from engagement with the disc 80 when the blanket is about to engage the paper. Similarly, the cam, cam follower, and microswitch provide the signal to the registration solenoid to energize the solenoid and thrust the finger into engagement with the disc, stopping and registering the paper, when the blanket disengages from the paper. In operation it is preferable to size the cam so that it has a slightly larger angular displacement than the blanket to ensure that the paper has been released by the registration station prior to engagement by the blanket, and also to ensure that the blanket has disengaged from the paper prior to it being reregistered and immobilized by the registration station. In FIGURES 1 and 5, the angular displacement of the cam is aligned with the angular displacement of the printing blanket, and the cam follower and microswitch have been positioned at the bottom of the plates 112 to correspond with the position that the blanket will engage the paper. A moments reflection will reveal that the microswitch may be positioned anywhere about the periphery of the plates and that the cam may be rotated out of alignment with the blanket so long as the cam and microswitch are respectively positioned so as to cause the microswitch to generate a signal when the blanket is about to engage the paper and again when it has disengaged from the paper. In order to discourage the paper from unwanted movement with respect to the processing unit, yet allow the paper to be freely moved by the paper feeder and the registration station, applicant has found that it is preferable to provide a degree of resistance, analogous to the drag of a fishing reel, to movement of the paper. For this purpose a vacuum brake 120 as shown in FIGURES 2, 3, and 6 is positioned at the infeed end of the press. The vacuum brake merely consists of a sealed tube 122 having a plurality of holes 124 formed therein. Vacuum is applied to the inside of the tube and creates a suction force at the holes to provide some resistance to paper movement past the holes. A keeper arm 126 tucks the paper around the tube to maintain the paper in contact with the holes. Applicant has also determined that it is preferable to provide a shock absorber to cushion the paper from sudden stops and starts which could tear the paper. The buffering device shown most clearly in FIGURES 2, 3, 6 and 7 is commonly called a dancer 128 in the printing trade, taking its name from its characteristic up-and-down motion while in operation. The dancer includes an elongate bar 130 extending across the paper path and resting upon the paper. Each end of the bar is bent so as to have an ear 132 extending parallel to the axis of the bar. The bar is pivotally supported at each end by blocks 134 which have bores formed therein to receive and retain the ears of the dancer. As may be seen in FIGURE 7, a spring 136 urges the bar down upon the paper and a set screw 138 limits the upward pivoting of the bar. The purpose and operation of the dancer is most readily explained with reference to FIGURE 3. Movement of the paper through the press causes the disc 80 to rotate counterclockwise. Because the registration station cannot stop and register the paper until after it has been released by the paper feeder, the disc will typically advance to a position illustrated by line a'. When the finger 86 thrusts into engagement with the disc 80, it will counter rotate the disc to a position illustrated by line b'. This counter rotation of the disc backs up the paper 16, creating slack or surplus. The spring-biased dancer 128 takes up the slack as shown in FIGURE 3. When the paper is reengaged by the paper feeder and released by the registration station the dancer absorbs the shock caused by the sudden movement of the paper. Without the dancer, or some other form of buffering device, this sudden movement, coupled with the slack in the paper would be likely to tear the paper. The present invention is particularly useful to convert a pre-existing processing unit, of the type adapted to process individual sheets of paper, to process continuous form paper. As may be seen in FIGURES 1 through 4, the registration station does not need to be operatively connected to the examplary press, nor does it need to be precisely positioned with respect to the press. The registration station merely ensures that exactly one predetermined increment has been pulled through the registration station each cycle. If slightly more or slightly less than a predetermined increment has passed the registration station, the window concept described above will move the paper forward or backward accordingly, re-registering the paper to the printer each cycle. Since the paper is engaged on the pin belt, the paper cannot slip with respect to the registration station. Because the registration station is neither operatively connected nor precisely positioned with respect to the press, if may be easily and quickly bolted on and off the press. Alternatively, only that portion of the registration station which interferes with the printing of single sheets needs to be removed. In the case of a wet offset press of the type shown in the drawings, it is not necessary to provide a separate paper feeding station since the operation of the printing blanket, blanket cylinder and impression cylinder will serve as a paper feeder to feed continuous paper in discontinuous pulses. However, it is necessary to provide timely signals to the registration station to register and hold the paper in registration, and to release the paper when the next increment of paper is fed to the press. It may also be desirable to provide additional electrical control signals between the press, the registration station and the paper feeder, as well as the aforementioned control signals between the paper feeder and the registration solenoid. When beginning printing operations with an offset press, it is customary to disengage the blanket cylinder from the impression cylinder so that the blanket cylinder and the ink cylinders may be rotated to "ink up". To avoid feeding paper through the press during this process when no printing is being accomplished, a press solenoid 139 is connected to a pivotable arm 140 which supports the shaft 142 of the impression cylinder 20. When this solenoid is activated it drops the impression cylinder away from the blanket cylinder so that the press will not feed or print paper. The press solenoid is controlled through a relay by a second microswitch (not shown) co-located with the first microswitch 118, to ensure that the press solenoid does not disengage the impression cylinder when the press is feeding the printing paper nor engage the impression cylinder when the registration station has the paper immobilized. Those familiar with this art will realize that there are readily available alternatives for many of the features described and shown herein. For example, an optical scanner of the type adapted to count pin holes, a tachometer generator, or a variety of state-of-the-art motion detectors employed in conjunction with computers, may be used instead of the cams shown herein to determine when a predetermined increment has been fed to the press and so provide a signal to the registration station. The terms and expressions which have been employed in the foregoing specification are used therein as terms of description and not of limitation, and there is no intention in the use of such items and expressions of excluding equivalents of the features shown and described or portion thereof, it being recognized that the scope of the invention is defined and limited only by the claims which follow.

Claims: A printing press (10) adapted to discontinuously feed continuous form paper (16) and to print said paper at a printing station thereof, said press being provided with: (a) registration means (66,80,86), located at a registration station (12) upstream of said printing station, for maintaining the continuous form paper (16) in proper registry; (b) sensing means (114,116) for detecting each time a predetermined form length of said paper is fed forwards through the press; and (c) electrical control means (118,84), in operative association with said sensing means and with said registration means, effective to control activation of said registration means (66,80,86) and thereby cause the latter to index the continuous form paper (16) and to arrest further movement thereof each time the sensing means (114,116) detects a feed of a said predetermined form length of the paper, characterised in that (i) the printing press (10) is of the type having a blanket cylinder (18) carrying a printing blanket (22) which co-operates with an opposed impression cylinder (20) to effect printing and also to discontinuously feed the paper through the press, in that (ii) the co-operation between said blanket-carrying blanket cylinder and said opposed impression cylinder provides the sole feed means for feeding the continuous form paper (16), the circumferential length of the printing blanket (22) being matched to said predetermined form length of the paper and said registration means (66,80,86) being operable without any paper moving function other than that of selectively moving the paper backwards or forwards to adjust its position during indexing, and in that (iii) the sensing means (114,116) is operatively associated with said blanket cylinder (18). A press as claimed in Claim 1 wherein said registration means (66,80,86) includes paper engaging means (66) which is arranged to maintain continuous engagement with said paper and which is freely movable during feeding of the continuous form paper (16) while the registration means is de-activated. A press as claimed in Claim 2 wherein said paper engaging means (66) is separate and mechanically independent from said blanket cylinder. A press as claimed in Claims 2 or 3 wherein said registration means (66,80,86) includes detent means (86) arranged selectively to interact with said paper engaging means (66) in response to activation by said electrical control means (118,84), thereby to bring about the indexing and arrest of the continuous form paper (16), the speed of operation of said detent means (86) being independent of and unrelated to the operating speed of the blanket cylinder (18) of the press. A press as claimed in Claims 2 or 3 wherein said registration means (66,80,86) includes detent means (86) arranged selectively to interact with said paper engaging means (66), in response to activation by said electrical control means (118,84), through an indexing element (80) thereby to bring about the indexing and arrest of the continuous form paper (16), said indexing element (80) comprising a rotatably mounted low mass disc-like body operatively connected to said paper engaging means (66) and provided with a ring of circumferentially-spaced projections (82) extending parallel to the rotational axis of said body and defining a series of circumferentially-spaced gaps for engagement with said detent means (86). A press as claimed in any one of the preceding claims wherein the registration means (66,80,86), sensing means (114,116) and electrical control means (118,84) form a removably fitted attachment whereby the printing press (10) is reversibly converted from a press suitable only for feeding and printing single sheets of paper to a press suitable for discontinuously feeding and printing continuous form paper (16) as aforesaid. A press as claimed in any one of the preceding claims wherein the blanket cylinder (18) and the impression cylinder (20) of the press are capable of being selectively moved apart from each other so as to permit said blanket cylinder (18) to rotate without engaging said paper, and wherein further control means (139,40) are provided for preventing said blanket cylinder (18) and impression cylinder (20) from being moved apart while the paper (16) is being fed and printed and/or for preventing said blanket cylinder (18) and impression cylinder (20) from being re-engaged while movement of the paper is arrested during activation of the registration means (66,80,86). Apparatus used for modifying a printing press to enable or facilitate it to print discontinuously fed continuous form paper at a printing station of the press, said apparatus comprising: (a) registration means (66,80,86) for maintaining the continuous form paper (16) in proper registry at a registration station (12) upstream of said printing station; (b) sensing means (114,116) for detecting each time a predetermined form length of said paper is fed forwards through the press; and (c) electrical control means (118,84), in operative association with said sensing means and with said registration (66,80,86) means, effective to control activation of said registration means and thereby cause the latter to index the continuous form paper (16) and to arrest further movement thereof each time the sensing means (114,116) detects a feed of a said predetermined form length of the paper, characterised in that (i) said apparatus does not include any paper-feeding means, said registration means (66,80,86) being operable without any paper moving function other than that of selectively moving the paper backwards or forwards to adjust its position during indexing, in that (ii) said apparatus forms a removable attachment and is used to reversibly convert a press (10) designed to feed and print only single sheets of paper to a press capable of discontinuously feeding, printing and maintaining in proper registry continuous form paper, said press being of the type having a blanket cylinder (18) carrying a printing blanket (22) which co-operates with an opposed impression cylinder (20) to effect printing and to discontinuously feed paper through the press, the co-operation between said blanket-carrying blanket cylinder (18) and said opposed impression cylinder (20) providing in use the sole paper feeding means, and in that (iii) in use said sensing means (114,116) is operatively associated with said blanket cylinder (18). Apparatus as claimed in Claim 8 wherein said registration means (66,80,86) includes paper engaging means (66), separate and mechanically independent from said blanket cylinder (18), which is arranged to maintain continuous engagement with said paper and which is freely movable during feeding of the continuous form paper (16) while the registration means is de-activated. Apparatus as claimed in Claim 9 wherein said registration means (66,80,86) includes detent means (86) arranged selectively to interact with said paper engaging means (66) in response to activation by said electrical control means (118,84), thereby to bring about the indexing and arrest of the continuous form paper (16), the speed of operation of said detent means (86) being independent of and unrelated to the operating speed of the blanket cylinder (18) of the press. Apparatus as claimed in Claim 9 wherein said registration means (66,80,86) includes detent means (86) arranged selectively to interact with said paper engaging means (66), in response to activation by said electrical control means (118,84), through an indexing element (80) thereby to bring about the indexing and arrest of the continuous form paper (16), said indexing element (80) comprising a rotatably mounted low mass disc-like body operatively connected to said paper engaging means (66) and provided with a ring of circumferentially-spaced projections (82) extending parallel to the rotational axis of said body and defining a series of circumferentially-spaced gaps for engagement with said detent means (86).

Inventors: MCANELLY, JAN
Applicants: CONTINUOUS GRAPHICS, INC.
Application year: 1986
Main classification: B41F13
IPC codes: B65H20, B65H23, B41F13