US3667353A

US3667353A - Web fed rotary variable repeat cutter-creaser system

Info

Publication number: US3667353A
Application number: US743748A
Authority: US
Inventors: Henry D Ward Jr; Floyd Steinmetz
Original assignee: ROTOGRAPHIC MACHINERY CO
Current assignee: ROTOGRAPHIC MACHINERY CO
Priority date: 1968-07-10
Filing date: 1968-07-10
Publication date: 1972-06-06
Anticipated expiration: 1989-06-06
Also published as: NL6815312A; GB1217356A; JPS5138953B1; CH493399A; DE1812396B2; DE1812396A1; SE337523B; FR1587560A; BE721901A

Abstract

A web fed rotary variable cutter-creaser system is provided for the packaging industry which is to be fed from a web stock of material either printed or unprinted or both. This system consists basically of a pair of large diameter, very heavy walled drums on which can be mounted a pair of cutting and creasing dies. These dies are in the form of a sheet metal blanket into which the shaped to be cut and creased have been chemically milled. The dies are mounted on these two drums so that as they rotate together, the dies will match one another in a registered position. A feeder is provided for the die cylinders which has the qualities of feeding a selected length of material, yet is continuously supplied from a roll web stock of material. A crank working directly from the die cylinders forms storage loops in the web and advances it periodically. Swing rolls are oscillated by the crank arm and these are geared to a mechanism for advancing or retarding the fed portion of the web of material in accord with registration marks on the web stock.

Description

United States Patent Ward, Jr. etal,

[is] 3,667,353 1 June 6, 1972 [72] Inventors: Henry D. Ward, Jr., Phoenix; Floyd Stein rnetz, Timonium, both of Md.

The Rotographic Machinery Company, Baltimore, Md.

[22] Filed: July 10, 1968 [2i] Appl.No.: 743,748

[73] Assignee:

52 'u.s.c1. ...93/58.2 R, 226/] 13 51 lm.Cl ..B3lb 1/16 58 FieldofSearch ..93/58,58.2, 58.3, 80, 93 DP;

Primary ExaminerBemard Stickney AtromeyWalter G. Finch v ABSTRACT.

A web fed rotary variable cutter-creaser system is provided for the packaging industry which is to be fed from a web stock of material either printed or unprinted or both. This system consists basically of a pair of large diameter; very heavy walled drums on which can be mounted a pair of cutting and creasing dies. These dies are in the form of a sheet metal blanket into which the shaped to be cut and creased have been chemically milled. The dies are mounted on these two drums so that as they rotate together, the 'dies will match one another in a registered position.

19 Claims, 8 Drawing Figures PAIENIEDJUN 61912 3.661353 SHEEIZ 0F 4 FIXED DR/ VE ROL L S CRIZVK PA TH REGISTER DIE DRUMS WEB/ A 26 GUIDE 8/] Rs /28 All? PRESSURE sums OSCILLATING DRIVE mus BEG/IV FORWARD MOT ION CUTTING DIE FIG. 3. BEG/N our WEB SPEED- D/E DRUMS SP-EED v REG/57E}? CONT/90L $EN$0 igfiygfi 96 /0PERATOR'$ PANEL AND 92 CONTROLLER ROLL ANGULAR POSITION MON/TOR PATENTEDJUM 6I972 3,667,353

snmwa STOP FORWARD MOT/0N START REARWARD M07 ION V=0 WI THDRA W WEB WEB FED ROTARY VARIABLE REPEAT CUTTER- CREASER SYSTEM This invention relates generally to cutting and creasing machines, and more particularly it pertains to a web fed rotary variable repeat cutter-creaser system for use in the packaging industry.

One of the major unsolved problems facing industry today relates to die cutting, creasing, embossing, or printing webs of material with an infinite variety of repeat lengths.

In the past, the method for producing a variable cut or print length on a web stock of material has been to either change the diameter of the printing or cutting cylinder of the machine to suit the repeat length that is being produced on the web, or secondly to feed a variable length of web material between two heavy tables or platens which can then cut the particular length of web fed between them. At that point, the platens open again, and again a length of web of material is fed into them.

Another method to accomplish the above has been to first cut the web of material into sheets of the length required and then to feed the sheets through a platen or between rotary drums. In this last method, of course, there is no problem with feeding a variable sheet length. Whatever sheet is fed into the machine, can simply pass straight on through the machine and it is only necessary to feed one sheet per revolution of the machine to produce a variable cut or print length.

To clarify matters, it is well to define variable repeat length" here. By this, it is meant that adjustments can be made to a cutter-creaser type system to cut any length of stock required within the specific limits. Out of the material that is being fed through the system, the length of cut must be variable in the direction of sheet travel and if a web stock of material is being fed through a cutter-creaser, this stock may be printed with a repeat pattern, with one printed pattern appearing, for example, every 25 inches on the sheet.

If the sheet is to be cut into paperboard containers, Such as for ice cream containers, the cut length must be positioned directly and exactly on the printed matter and the cut'length must be exactly the length of the repeat of the printing without cumulative error. The next order, for instance, could be bacon board made from a different and unprinted roll of paper stock, and the repeat might be 38 inches long, for example.

Basically, the problem is to produce this variable repeat length of cut accurately. To produce the highest running speeds, it is desirable to use a pure rotary motion for the cutting action. This is because the cutting and creasing loads are of a fairly high magnitude and this means that the structural members, such as the platen tables, which are used in platen presses, have to be extremely massive to be rigid enough to resist deflection under the cut and crease loads and, therefore, a reciprocating motion of the cutting mass and limits the physical speed of the machine. For this reason, it was found that a pure rotary motion of a pair of drums lends itself to much higher running speeds. 1

Secondly, it was deemed essential that there be a smooth feed of the web stock of material into the system. On a platen press, for example, the stock must be fed into the machine while the platen tables are open. The web stock of material has to be stopped and held in a stationary position while the platens are brought together for the cutting operation. This, of course, means that the running motion of the machine has momentarily stopped and therefore, production has, in efiect, been lost. Thirdly, it was necessary to use drums of a fixed diameter on which there are mounted cutting dies or perhaps printing plates or dies of different lengths to eliminate the requirement to physically change drums in order to produce a different drum circumference which, in turn, would produce a different sheet length or repeat length.

It is common, for instance, on milk container rotary cuttercreasers to manufacture the entire machine for a specific sheet length, with a specific diameter of drum being used.

On various web printing presses in order to change repeat lengths, it is necessary to change the entire drum which carries the printing dies or plates to obtain the exact repeat length desired. In a regular jobbing shop for producing a variety of different types and kinds of boxes, this conversion or interchange of drums is a time consuming operation and is undesirable because of high cost It is also highly desirable to have a web fed machine rather than a sheet fed machine in order to allow the most economical use of paper stock. Quite often the shape which is to be cut from the paper stock is irregular and it is ofien designed so that the cut patterns will interlock with one another, thereby reducing the amount of waste paper around the edge of the cut.

Obviously, if the stock must be cut into sheets and then printed and die cut, these sheets will be rectangular and all of the material around the edges of these irregular blanks will be lost. On the other hand, if a regular web fed machine is used, the irregular cuts can be planned to interlock with one another and reduce the waste stock to a minimum.

In boxes of this type, the cost of the material itself is a large portion of the cost of the box and any savings that can be introduced into the operation through a reduction in the amount of material used has a very real and very direct effect on the cost of the boxes themselves.

It is an object of the present invention, therefore, to provide a cutter-creaser system which positively feeds predetermined isolated increments of continuous web stock into the die rolls.

Another object of this invention is to provide a variable repeat cutter-creaser system which feeds a predetermined length of patterned material in register into the dies which are mounted in the die cylinders. I

Still another object of this invention is to provide a feeder system for die cylinders which has the qualities of individual blank feeding, yet is continuously supplied from web stock.

Other objects of this invention are to provide a web fed rotary variable repeat cutter-creaser system in which variable repeat lengths of cut are made at the highest running speeds of the system.

To provide a web fed rotary variable repeat cutter-creaser system which is continuously fed with web stock of material, is still another object of this invention.

Also, even another object of this invention is to provide a web fed variable repeat cutter-creaser type system having drums of a fixed diameter on which there are mounted cutting dies of different lengths to'eliminate the requirement to physically change drums in order to produce the drum circumference which, in turn, would produce a different sheet length or repeat length. 7

And another object of this invention is to provide a cuttercreaser system which is web fed in order to allow the most economical use of web stock of material.

Other objects and attendant advantages of the invention will become more readily apparent and understood from the following detailed specification and accompanying drawings in which:

FIG. 1 is a side elevation in diagrammatic form embodying the components of a web fed variable repeat cutter-creaser system;

FIGS. 2, 3, 4, 5, and 6 are diagrammatic views showing in sequence, the stages of one cycle of operation of the members of the system of FIG. 1.

FIG. 7 is a graphical representation of a curve showing increase in web speed versus crank angle from the cuttercreaser system of the present invention; and

FIG. 8 isa schematic of a control arrangement for the web fed variable repeat cutter-creaser system of the present invention.

Referring now to the details of the invention as shown in FIG. 1, reference numeral 10 indicates generally a preferred embodiment of the novel web fed rotary variable repeat cutter-creaser system of this invention. This system 10 will first be described generally and then followed by a detailed description of the main parts thereof. A main drive 12 attached to the structure S of the system is the prime power source at variable speed for the cutter-creaser system 10.

A main drive gear 13 on the drive 12 meshes with an idler gear 14 on a shaft 16. This idler gear 14 meshes with a gear 18, which is secured to an upper die drum 20 carrying dies 22 for creasing or cutting operations.

Another gear 24 meshes in l to 1 ratio with gear 18 and it is secured to a lower die drum 26 carrying the lower dies 28.

It should be understood the lower drum 26 is adjustable vertically, longitudinally and circumferentially by means not shown, to accommodate respectively different web thicknesses of material and to register the dies 22 and 28.

The idler gear 14 also meshes with an input gear 30 of a positive infinitely variable drive 32. Because'this drive32 has a limited speed range, a set of change gears 34A, 34B etc. (only one of which is used at any given time) is supplied for taking off the output of the drive 32.

To mesh with the difierent diameters of these change gears, an idler gear 36 is provided, which is journaled on a trunnion 38. The trunnion 38 is fastened to a saddle 40 which pivots about a shaft 52. A yoke 42 which is joumaled with the idler gear 36 has an adjusting screw 44 extended through a threaded post 46. Post 46 is pivotally secured to the structure S of the system 10. In this manner, by advancing the adjusting screw 44, the idler gear 36 can be advanced from the position shown in solid lines to the position 36A shown in phantom lines to accommodate the largest diameter gear 34A or the smallest gear 34B of the change gear set previously mentioned.

The idler gear 36 further meshes with a gear 48 which rotates on the shaft 52. Oscillating arms 50 also pivot on the shaft 52 and they carry a pair of swing feed rolls 54 and 60. The upper swing feedroll 54 has a gear 56 which is meshed with the gear 48 and also meshes .witha gear 58 on the lower swing feed roll 60, the latter in l to 1 ratio.

A connecting rod or crank 62 from a pivot 64 on the oscillating arms 50 extends to a crank disc 66 and is coupled thereto by a crank pin. This crank disc 66 is attached by bolts 70 to the end of the die drum 20. This attachment is circumferentially adjustable through the medium of arcuate slots 68 for the bolts 70 and thus varies the relative phase angle between the sweep of the crank 62 and the rotation of the dies 22.

. The stroke length of the connecting rod or crank 62 is adjustable by means of aslot 72 which receives the crank pin and allows the pivotal radius to be selected.

'A buffer or air cushion is provided at reference 74, the cylinder of which is pivoted at 76 from the machine structure S. The piston rod 78 of this air cushion 74 is attached to the oscillating arms 50 with a connecting pin 80.

Reference numerals 82 designate drive feed rolls which are driven as will be related to advance the roll stock material web Win the direction of the arrows.

In addition to passing it between the swing feed rolls 54 and 60, a pair of

guides

84 and 88 define a path for the web stock W to the engagement line of

die drums

20 and 26. Clearance grooves 90 in the swing feed roll 60 are provided for the guide 88 with the latter havinga suitable radius of curvature to accommodate the sweep as arms 50 oscillate. A negative air pressure is maintained within the extended length of guide 88.

A positive air pressure, however, is maintained within the former guide 84. Both'these air pressures are communicated to the web stock W through means in the respective guides (not shown) such as open tops or perforations.

A register control sensor 86 which through well-known means such as printed marks on the web stock W viewed by light sensitive cells, signals the positive infinitely variable drive transmission 32 to cause a readjustment of the speed of output to correct misregister of printed matter on the web stock W with the dies 22 and 28. i The guide 84 is curved to allow a first reservoir loop to form in the web stock W at certain times in the cycle of operation. Midway in the cycle of operation, this first loop is formed over the discharge end of guide 88 as shown in FIGS. 2 and 4 respectively. In FIGS. 5 and 6, the first reservoir loop is being reformed, while FIG. 3 shows the system 10 in the position of the beginning cut.

The type of dies 22 and 28 envisioned for use on this cuttercreaser system 10 are of the chemically etched or milled type as described in U.S. Pat. No. 3,244,335 issued Apr. 5,1966, entitled Method for Forming Severance Lines," issued to R. H. Downie. Of course, it is not essential that the cutter-creaser system 10 be limited to these specific dies 22 and 28. Conventional rotary dies such as are used for the manufacture of milk containers would be perfectly satisfactory for mounting on the die drums 20 and 26. Y

Fixed ahead of these

rotary drums

20 and 26 as previously indicated by reference to FIG. 1 are the pair of swing feed rolls 54 and 60, which are mounted on the pair of oscillating arms 50 which, in tum, are linked together with the heavy torque shaft 52 to make sure that the swing feed-

rolls

54 and 60 rock back and forth and remain parallel to the two die

drums

20 and 26.

The swing feed rolls 54 and 60am geared together and are driven by the large gear 48 which is mounted on the center line of the torque shaft 52 previously mentioned. As the two swing feed rolls 54 and 60 rock back and forth on their arms 50 about the center of the torque shaft 52, their gears also rock back and forth around the large drive gear 48.

This means that a web stock W of material which is gripped between these two swing feed rolls 54 and 60 is driven by a speed which is the sum of the rotational speed of the large gear 48 plus the additional speed imparted by the rotation of the roll drive gears 56 and 58 about the large gear 48 plus the linear forward displacement of the swing feed rolls 54 and 60 themselves so that what is produced is 'a curve of motion which is the sum of a continuous speed which is the average speed of the web stock W and which is then modified by a speed which varies somewhat like a sine wave, upwards and downwards once each revolution of the

main drums

20 and 26, as best illustrated in FIG. 7. It is assured that this wave is produced once each revolution of the die drums 20 and 26 because the arms 50 on which the swing feed rolls 54 and 60 are mounted are linked back-to the crank pin on the drum 20.

It should be pointed'out that the large gear 48, which is sometimes called a bull gear and which is mounted on the torque or rocker shaft is also geared back through the gear train and the variable speed transmission 32 to the

gears

30, 14, and 13 which drive the two main cutting drums 20 and 26.

This allows a variation of the speed of the bull gear 48 and,

therefore, the average feeding'speed of the two swing feed rolls 54 and 60 by varying the gear ratios in the gear train and also by varying the drive ratio through the variable speed transmission 32.

Turning now to the speed curve of FIG. 7, there isshown, I

for example, a condition in which the

main drums

20 and 26 are running at such a speed as to produce a surface speed on the dies 22 and 28 of 980 surface feet per minute at a predetermined speed. If, for example, a repeat length on the web stock W of 57.7 inches is to be cut, the gear ratio would be adjusted by the variable speed transmission 32 to produce an average feed into the system 10 of 750 feet per minute surface speed on the feed rolls 54 and 60. This produces a differential in feeding speed of the web stock W relative to the cutting dies 22 and 28 of 230 feet per minute.

This speed of 230 feet per minute is then added to the feeding speed of the web stock W by the forward rocking motion of the swing feed rolls 54 and 60 about the torque shaft 52. This means that at the instant of the beginning of the cut, the web stock W of material will be entering the cutting point directly between the two die

drums

20 and 26 at substantially the surface speed of the cutting dies 22 and 28.

If then, it is desired to change the system 10 to produce a cut repeat length of 28.8 inches, this would, of course, necessitate changing the length of the cutting dies 22 and 28 on the

drums

20 and 26 to new dies which are 28.8 inches long.

The varying cut length is produced by simply varying the length of the cut pattern on that die 22 and 28.

Let it now be assumed that a

die

22 and 28 have been mounted on cutting

drums

20 and 26 which cutting length is 28.8 inches. The gears can be changed, together with the setting of the variable speed transmission 32 to produce a web speed of 375 feet per minute. This produces a speed differential if the

drums

20 and 26 are run with the surface speed of 980 feet per minute as previously mentioned. This produces a differential of 605 feet per minute between the die speed and the web speed. The motion of the arms 50 can be adjusted to cause the addition of 605 feet per minute by moving the swing feed rolls 54 and 60 forward at a corresponding speed, so that once again the web stock W is inserted into the leading edge of the cutting dies 22 and 28 between the two

drums

20 and 26 at a net 980 feet per minute.

The correcting action of the swing feed rolls $4 and 60 and their affect on the web stock W can be adjusted by selecting a different point on the speed curve of FIG. 7. This is done by moving the crank pin which is mounted on the end of cutting drum 20. The angular relationship of that crank pin to the leading edge of the cutting dies 22 and 28 can be moved. This in effect means that the web stock W is inserted between the cutting dies 22 and 28 at a higher point on the speed curve of the roll motion to produce a greater speed correcting action, such as is required for short cut lengths. Or, the crank pin can be adjusted to a different position to cause the web stock W to be inserted between the cutting dies 22 and 28 at a lower point on the speed curve such as a point near the end of the roll stroke where the forward motion of swing feed rolls 54 and 60 is relatively much smaller. This would be the case for instance when a longer cut length is being fed.

In the particular design of system 10, the crank pin which produces the rocking motion of the swing feed rolls 54 and 60 is mounted on the end of the rotary cutting drum 20. Of course, it is not necessary that this crank pin be located there. It could be mounted on any gear in the drive train which makes one revolution per revolution of the cutting drum 20. A simple crank motion has been used for the connecting rod or crank 62 such as shown in FIG. 1, materially forsimplicity. It would also be possible to drive the oscillating arms 50 with a cam mechanism or any similar device. 7

It is also to be pointed out that a straight line motion back and forth could be used for the swing feed rolls 54 and 60 rather than having them rock back and forth around a torque shaft 52. In that particular mechanism, the gears which drive the feed rolls engage a rack which would be fixed in the system and a speed change is produced by shifting the rolls back and forth along this rack. However, such an arrangement using a rack, does not produce an easier motion as does the motion described for the swing feed rolls 54 and 60. In system 10, a combination of changed gears together with a variable speed transmission 32 produces the varying driving speed between the die cut

drums

20 and 26 and the bull gear 48.

This was done specifically this way because the change gears give an absolute speed ratio. Unfortunately, one set of change gears must vary from the next by a fixed increment of whole numbers of teeth and here it was desirable to have an infinitely variable ratio without steps from one cut length to another. Therefore, the variable speed transmission 32 was introduced into the creaser-cutter system 10. Its speed adjustment range is quite narrow and its purpose is simply to allow for a slight modification to the particular gear ratio which has been selected so as to give a smooth and infinite transition of speed ratios from that which is produced from one change gear set to the next.

It is to be noted that one problem foreseen in inserting the web stock W into the cutting dies 22 and 28 is the fact that a relatively long free end of web stock W is being pushed from the drive and swing feed rolls 82, 54 and 60 into the die cut

drums

20 and 26. For this reason, a series of vacuum bars 88 were added along the track of the web stock W from the swing feed rolls 54 and 60 into the die cut

drums

20 and 26 and these bars 88 are equipped with a perforated surface through which a slight suction is applied. This suction effort will be just enough to be sure that the web stock W of material is held firmly along the surface of the guides and yet will still be free to slide. This will have the effect of definitely controlling the position of the web stock W and will impart a certain amount of support to the web stock W to prevent buckling as the protruding end of the web stock W is accelerated forward into the nip of the cutting dies 22 and 28. In addition, the curve of the guides will impart a slight curve to the web stock W to increase its stability.

As previously indicated, a secondary pair of drive feed rolls 82 are provided the purpose of which is to be sure that a free loop always exists ahead of the rocking or swinging feed rolls 54 and 60. The secondary drive feed rolls 82 would be pulling the web stock W of material from the primary roll or other source. The material would be lead through an edge guiding and tension controlling set of equipment which is conventional in the industry and would be pulled by. these drive feed rolls 82 to produce this loop. A loop scanner 100 could be provided to make sure that a loop is produced always within certain limits so that it is known, as the rocking or swinging feed rolls 54 and 60 move forward, there is always a sutficient amount of free material of the web stock W for them to consume and feed into the die drums 20 and 26.

These secondary drive feed rolls 82 are separately driven and their speed would be controlled to follow the speed of the system 10 as a whole. Electrically, the feeding speed of the drive feed rolls 82 can be modified by the loop scanner 100 to be sure that the free loop always exists. For example, if it is found that the loop is beginning to get too short, the loop scanner 100 would tell the secondary drive feed rolls 82 to speed up slight, and if the loop was beginning to get too long, the loop scanner would tell the drive feed rolls 82 to slow down slightly.

System 10 was developed as a pure rotary machine, with no high accelerations and decelerations to throw off the accuracy of the machine with the sole exception of the rocking motion of the swing feed rolls 54 and 60.

In order to smooth out the affect of the acceleration of the rocking mechanism, a link from the rocking or oscillating arms 50 was added which carry the swing feed rolls 54 and 60 back to the frame of the system 10. This link is in efiect the air cushion cylinder 74 which operates more or less like a shock absorber. The compression of air in the air cushion cylinder 74 on the return stroke of the

rolls

54 and 60, for instance, will contribute to decelerating the rocking or oscillating arms 50 and the swing feed rolls 54 and 60. On the feed stroke, of course, the pressure which has been built up into the swing feed rolls 54 and 60 will assist in accelerating the

rolls

54 and 60 in the forward direction.

Generally, a printed repeat pattern is provided on the web stock W of material being fed into the system 10. A set of change gears has been provided, together with a speed ratio in the variable speed transmission 32 so as to produce the same cut length in the system 10 that occurs in the web stock W on the printed matter. Of course, this can only be done to a certain degree of accuracy. This error would occur for instance, in the setting of the variable speed transmission 32.

It may also occur in the length of the printed repeat on the web stock W. For example, if the material of the web stock W stretches or shrinks slightly through its length due to changes in moisture content, the repeat length will change slightly and it is necessary for the system 10 to automatically correct itself as it runs so that each cut will be located directly on each printed pattern.

For example, if only one thousandths of an inch error is being made in cut length, after 1,000 cuts, 1 whole inch of material would be out of register unless a continuous correction were made.

Thus, to remedy this error, the scanning eye or register control sensor 86 has been added. This register control sensor 86 is a photocell which is located directly over the web stock W as it enters the swing feed rolls 54 and 60. This eye would pick up a register mark which is part of the printed matter. It picks up the position of the printing on the web stock W. An additional sensor or roll angular position monitor 92 is provided as shown in FIG 1 on the end of one of the cutting drums, for example, drum 20 which continuously senses the position of the cutting drum 20 in the system 10, that is, its rotary or angular position. A signal from each of sensor 86 and monitor 92 is then fed back into an electrical control system 96, as shown in FIG. 8, which is more or less a computer which then, taking these two sensing signals, can detect any error in the desired position of the cutting

drum

20 and 26 relative to the printed web stock W.

' At this point, an error signal can be sent to a small motor or compensator actuator 94 which, in turn, controls the speed ratio setting in the variable speed transmission 32 causing the transmission to introduce a correction into the gear train which is driving the swing feed rolls 54 and 60. This, in turn,

1 will advance or retard the material of the web stock W slightly so that the cut will then be continuously re-registered to the printed matter on the sheet at each cut. This will insure that although some errordoes occur, or can occur, in each cut length, this error can be limited to within a very small margin.

Of course, it is to be noted that this system 10 has been developed to detect a printed register mark on the web stock W of material. Of course, this mark need not be a printed mark or even a mark at all. It can, for example, be a magnetic impulse which is imparted to the web stock W of material at the required intervals or it could be a hole punched through the web stock W of material.

in the cutter-creaser system 10 described so far, there are two

drums

20 and 26 involved, each of which carries a sheet metal type cuttingand creasing die 22 and 28, respectively. Of

. course, the general principles of this system 10 and can be applied, for example, to a variable repeat web fed printing press in which one drum would simply be a smooth cylinder to back up the web stock W of material. The other drum, for example, would carry the printing dies or plates which would be inked by a conventional inking mechanism. Or, if, for example, the system were to be used as a somewhat cruder form of cutting and creasing system, a single set of dies could be made by inserting a cutting rule in the curved plywood for example. This type of die is currently. being used onsheet fed rotary die cutters for corrugated board and the like.

a in that particular instance, thesystem would be designed so that one drum would accept the curved plywood die. The opposed drum would then be covered with a continuous blanket of a resilient material such as polyurethane and this would allow thecutting blades in the die to drive through the web stock being cut into the polyurethane.

Another possible variation of the cutter-creaser system 10 would be as a sheeter. A sheeter is a machine which takes a web stock of material and simply cuts it into sheets. In this case, for example, there need only be one drum which would carry a blade running along its length. It is common in sheeters for the matching blade to simply be a beam with a cutting edge on it mounted under the drum. As the cutting edge of the blade passes over the comer of the beam, a shearing cut is produced. In this type of design of the system, for example, there would only be one drum involved and a fixed beam would supply the other cutting member. In the case of the sheeter with only one drum, the rest of the mechanism that has been described here would still be used to produce the variable length of sheet feed per cut.

,There is another possible version of system 10, for example,.

where the two

drums

20 and 26 would be the main blanketcovered drums of an offset press, In this example, the top and bottom of the sheet could be printed on and the printed matter could be applied to both drums at the same time by a regular offset printing press mechanism.

Of course, with that kind of an application the change gears I and variable speed transmission 32 and the rest of the 'feeding mechanism would still be the same. The only thing that would change would be the particular surface configuration of the drums themselves.

Another possible variation to this design includes the variable speed ratio equipment between the cutting

drums

20 and 26 and the bull gear 48, with a combination of change gears and a variable speed transmission 32 being used. It is known that infinitely variable speed transmissions have a small percentage of error of the speed ratio through the transmission 32. In this instance of the present system 10, transmission 32 has been used to give a speed variation in very small increments which can be obtained by making a small change in the change gear ratio. Using the system this way, any error which matures through the variable speed transmission 32 is only a very small portion of the total speed ratio and, therefore, can be tolerated even on an extremely accurate machine.

It is quite possible that a variable speed transmission 32 can be designed which willhave an extremely accurate control of the ratio within the transmission itself. In this case, if this error is very small it then means that it would no longer be necessary to use change gears at all. The total control of sheet length range could be obtained by taking the entire drive ratio change in the transmission 32 itself and any slight errors which this extremely accurate transmission might produce would then be controllable by the automatic scanning and correcting devices, previously mentioned.

There is one other modification which is desirable to be made to the cutter-creaser system 10 under certain circumstances, which is the ability to adjust the radius of the crank pin at the end of the connecting rod 62, that is, the radius from the center of the crank pin to the center of the drum 20. This crank pin, through the connecting rod 62, drives the rocking motion of the swing feed rolls 54 and 60. It may be desirable to change this radius of the crank pin for different sheet length conditions, in order to produce the very minimum necessary acceleration in the rocking mechanism for each particular sheet length. This adjustment will onlybe necessary in each is desired to run the system 10 at very high web speeds such as in the neighborhood of 1,000 feet per minute or better.

As previously mentioned, the oscillating .arms 50 which carry the swing feed rolls 54 and 60 are connected to the shock absorbing type cushion cylinder 74 to help absorb or level out the accelerating and decelerating forces which are produced by the linear back and forth motion of the swing feed rolls 54 and 60 themselves. Of course, these swing feed rolls 54 and 60 are also accelerating and decelerating in a rotary direction about their own centers because their driving gears are rocking back and forth around the bull gear 52 which drives them. v

This introduces also a rotary accelerating and decelerating force back and through the gear train and for extreme accuracy it is desirable to absorb and level out back load.

To do this, an extra gear (not shown) has been connected to the bull gear 48. This extra gear drives a hydraulic pumping system. The valving in this system is such that once each revolution the connections through the hydraulic system are reversed so that the pump which is connected to this extra gear alternately becomes first a pump and then a hydraulic motor; so, during that period of the cycle in which the bull gear 48 is attempting to accelerate the swing feed rolls 54 and 60, the hydraulic system is valved to produced an auxiliary assist to the driving motion, and it helps to smooth out the loads back through the gear train. During that portion of the cycle when the bull gear 48 is attempting to decelerate the rotary motion of the swing feed rolls 54 and 60, the valving is then reversed so that this gear becomes the drive gear for a pump and it then absorbs the energy which is produced by the deceleration of the swing feed rolls 54 and 60.

Obviously many modifications and variations of the present invention are possible in light of the above teachings. It is,

therefore, to be understood that within the scope of the ap Q pended claims the invention may be practiced otherwise than as specifically described.

What is claimed is:

oneoperation on a web having structure including a work member positioned thereon for working on a continuously supplied web stock fed thereto during each working cycle of said work member, the improvement comprising means arranged to form storage loops in said web stock and advance said web stock periodically to said work member, and means coupled to said means for forming said storage loops and controlled by said structure having said work member to cause said storage loop means to feed a predetermined length of web stock to said work member for operation thereon by said work member.

2. A variable repeat length system for performing at least one operation on a web comprising, structure including a work member positioned thereon for working on a continuously supplied web stock fed thereto during each working cycle of said work member, means arranged to form storage loops in said web stock and advance said web stock periodically to said work member, and means coupled to said means for forming said storage loops and to said structure having said work member to cause said storage loop means to feed a predetermined and adjustable length of web stock to said work member for operation thereon by said work member.

3. A variable repeat length system for performing at least one operation on a web, comprising, means including a work member positioned thereon for working on a continuously supplied web stock fed thereto during each working cycle of said work member, means arranged to form storage loops in said web stock and advance said web stock periodically to said work member, and means coupled to said means for forming storage loops and to said means having said work member to cause said storage loop means to feed an adjustable length of web stock to said work member for operation thereon by said work member.

4. A rotary variable repeat length system for performing at least one operation on a web, comprising, means including at least one rotary drum having a work member positioned thereon for working on a web stock fed to said drum, feeding means arranged to feed said web stock to said rotary drum, means for causing said feeding means to travel through one complete control cycle for each revolution of said rotary drum, and means coupled to said feeding means and to said rotary drum to cause said feeding means to feed an adjustable length of web stock to said rotary drum'at substantially the surface speed thereof for operation thereon by said work member on said rotary drum.

5. A rotary variable repeat length system for performing at least one operation on a web, comprising, means including at least one rotary drum having a work member positioned thereon for working on a web stock having spaced indicia thereon fed to said drum, feeding means arranged to feed said web stock to said rotary drum, means for causing said feeding means to travel through one complete control cycle for each revolution of said rotary drum, and means coupled to said feeding means and to said rotary drum to cause a change in the feeding action of said feeding means to correct for misregister between said spaced indicia on said web stock and the work member on said rotary drum.

6. A web fed rotary variable repeat length system for performing at least one operation on a web, comprising, means including a pair of spaced rotary drums having work members positioned in register with one another thereon for working on a web stock fed between said rotary drums, feeding means arranged to feed said web stock between said rotary drums, means for causing said feeding means to travel through one complete control cycle for each revolution of said rotary drums, and means coupled to said feeding means and to one of said rotary drums to cause said feeding means to feed an adjustable length of web stock to said rotary drums at substantially the surface speed thereof for operation thereon by said work members.

7. In a web fed rotary variable repeat length system as recited in claim 6, wherein said feeding means includes a pair of spaced members mounted thereon for receiving and feeding said web stock to said rotary drums.

8. In a web fed rotary variable repeat length system as recited in claim 7, wherein said means coupled to said feeding means and to one of said rotary drums includes a variable ratio drive mechanism.

9. A web fed rotary variable repeat length system for performing at least one operation on a web, comprising, means including a pair of spaced rotary drums having work members positioned in register with one another thereon for cutting and creasing sections from a web stock having spaced indicia thereon and fed between said rotary drums, feeding means arranged to feed said web stock to said rotary drums, means for causing said feeding means to travel through one complete control cycle for each revolution of said rotary drums, drive means coupled to said feeding means and to one of said rotary drums, and means for sensing said spaced indicia on said web stock and the angular position of said rotary drums and for signaling said drive means to cause a change in the feeding action of said feeding means in order to correct for misregister of said spaced indicia on said web stock and said work members on said rotary drums.

10. A web fed rotary variable repeat length system as recited in claim 9, wherein said feed means is pivotally mounted and includes a pair of feed rolls for receiving and feeding said web stock to said rotary drums at substantially the surface speed thereof.

11. A web fed rotary variable repeat length system as recited in claim 9, wherein said drive means is of the variable ratio type.

- 1 2. A web fed rotary variable repeat length system as recited in claim 9, and additionally means for cushioning the movements of said feeding means.

13. A web fed rotary variable repeat length system as recited in claim 9, wherein said work members are work dies for cutting, creasing, embossing and/or printing of said web stock.

14. A web fed rotary variable repeat length system as recited in claim 9, and additionally feed rolls for continuously feeding web stock to said feeding means for further operation thereon.

15. A web fed rotary variable repeat length system as recited in claim 14, and means for sensing and controlling the rate of feed of said web stock to saidfeeding means.

16. A web fed rotary infinite variable repeat cutter-creaser system, comprising, means including a pair of spaced rotary members having work elements positioned in register thereon for cutting-creasing sections from a web stock having spaced indicia thereon fed between said rotary members, feeding means having spaced rolls mounted thereon arranged to receive said web stock between said rolls and feeding said web stock into said rotary members at substantially the surface speed thereof, means coupling said feeding means with one of said rotary members, a variable ratio drive means coupled to said feeding means and to said one rotary members, and means for sensing said spaced indicia on said web stock as well as the angular position of said rotary members and for signaling said variable ratio drive means to cause a readjustment of the speed of output of said variable ratio drive mean to correct for misregister of said indicia on said web stock with said work elements on said rotary members.

17. A variable repeat length system for performing at least one operation on a web, comprising, means having a work member positioned thereon for working on a continuously supplied web stock having spaced indicia thereon fed to said work member during the working cycle thereof, feeding means arranged to form storage loops in said web and advance said web periodically to said work member, means for causing said feeding means to travel through one complete control cycle for each cycle of operation of said work member, and means coupled to said feeding means and to said means having said work member to cause a change in the feeding action of said feeding means to correct for misregister between said spaced indicia on said web stock and the work member.

18. A web fed rotary variable repeat length system for performing at least one operation on a web, comprising means including a pair of spaced rotary members having work elements positioned in register with one another thereon for working on a continuously supplied web stock fed between said rotary members during the working cycle thereof, feeding means arranged to form storage loops in said web and advance said web periodically to said work elements, means for causing said feeding means to travel through one complete control cycle for each cycle of operation of said rotary members, and means coupled to said feeding means and to one of said rotary members to cause said feeding means to feed an adjustable length of web stock to said rotary members at substantially the surface speed thereof for operation thereon by said work elements.

19. A web fed rotary infinitely variable repeat cuttercreaser system, comprising, means including a pair of spaced rotary members having work elements positioned in register thereon for cutting-creasing printed carton sections from a continuously supplied web stock having spaced indicia thereon fed between said rotary members, feeding means arranged for feeding said web stock to said rotary members at substantially the surface speed thereof, means coupling said feeding means with one of said rotary members, drive means coupled to feeding means and to said one rotary member, and means for sensing said spaced indicia on said web stock as well as the angular position of said rotary members and for signaling said drive means to cause a readjustment of the speed of output of said drive means to correct the misregister of said indicia on said web stock with said work elements on said rotary members.

I! l II i

Claims

1. In a variable repeat length system for performing at least one operation on a web having structure including a work member positioned thereon for working on a continuously supplied web stock fed thereto during each working cycle of said work member, the improvement comprising means arranged to form storage loops in said web stock and advance said web stock periodically to said work member, and means coupled to said means for forming said storage loops and controlled by said structure having said work member to cause said storage loop means to feed a predetermined length of web stock to said work member for operation thereon by said work member.

4. A rotary variable repeat length system for performing at least one operation on a web, comprising, means including at least one rotary drum having a work member positioned thereon for working on a web stock fed to said drum, feeding means arranged to feed said web stock to said rotary drum, means for causing said feeding means to travel through one complete control cycle for each revolution of said rotary drum, and means coupled to said feeding means and to said rotary drum to cause said feeding means to feed an adjustable length of web stock to said rotary drum at substantially the surface speed thereof for operation thereon by said work member on said rotary drum.

12. A web fed rotary variable repeat length system as recited in claim 9, and additionally means for cushioning the movements of said feeding means.

15. A web fed rotary variable repeat length system as recited in claim 14, and means for sensing and controlling the rate of feed of said web stock to said feeding means.

18. A web fed rotary variable repeat length system for performing at least one operation on a web, comprising, means including a pair of spaced rotary members having work elements positioned in register with one another thereon for working on a continuously supplied web stock fed between said rotary members during the working cycle thereof, feeding means arranged to form storage loops in said web and advance said web periodically to said work elements, means for causing said feeding means to travel through one complete control cycle for each cycle of operation of said rotary members, and means coupled to said feeding means and to one of said rotary members to cause said feeding means to feed an adjustable length of web stock to said rotary members at substantially the surface speed thereof for operation thereon by said work elements.

19. A web fed rotary infinitely variable repeat cutter-creaser system, comprising, means including a pair of spaced rotary members having work elements positioned in register thereon for cutting-creasing printed carton sections from a continuously supplied web stock having spaced indicia thereon fed between said rotary members, feeding means arranged for feeding said web stock to said rotary members at substantially the surface speed thereof, means coupling said feeding means with one of said rotary members, drive means coupled to feeding means and to said one rotary member, and means for sensing said spaced indicia on said web stock as well as the angular position of said rotary members and for signaling said drive means to cause a readjustment of the speed of output of said drive means to correct the misregister of said indicia on said web stock with said work elements on said rotary members.