US2249938A - Printing plate anchorage - Google Patents

Description

' Y 1941? G. E. BOMBERGER ETAL 2,249,938

PRINTING PLATE ANCHORAGE Filed Feb. 23, 1940 Patented July 22, 1941 PRINTING ILATE ANCHOR/AGE George E.'Bomberger and Howard H. Niederauer, Indianapolis, Ind., assignors to Inland Container Corporation, Indianapolis, Ind., a corporation Application February 23, 1940, Serial No. 320,356 4 Claims. (01. 101-4151) This invention relates to the cylinder printing of corrugated, solid fibre, or like material containers.

In the printing of such material the runs may be large or small. However, the preparation of printing surface and its application to the printing press requires a fixed amount of time, regardless of the quantity of the orders. The container manufacturers are faced with a service problem which requires quick delivery of containers, and because of' the quick service the Because of the high cost of printing presses, or more particularly, combination printers and slotters, it is desirable that all possible preparatory work on a new printing surface sheet be done prior to the shut down of the press for the printing surface demounting and mounting This invention covers the bonding operations. of the printing dies to the printing surface sheet in the spaced relation necessary to meet the requirements of the container or board blank to be printed by each cylinder.

of the printing surface sheet and of a size suitable for engagement in the receptacles or anchorages provided in the printing cylinders.

The present practice in applying printing Strips of suitable material are then combined to two parallel edges ,20 This invention plates to the cylinders is to use one of the fol- L lowing processes.

1. In the case of wood cylinders, to place tacks through the printing surface sheets and the printing dies to the extent that both the printing surface sheet and printing die will conform to the curvature of the cylinder.

2. In the case of metal cylinders, the printing die is usually mounted on a curved metal backing which is locked with lugs to the cylinder.

3. In some cases the printing dies are bonded I to curved, punched, metal plates which can be tacked on to Wood cylinders. v

The chief feature of the invention is the accomplishment of said objects by utilizing a printing surface sheet which is flexible for support conformation and to which is secured by adhesion or the like, the impression forming means, the flexible printing surface sheet being relatively inextensible, and the mounting of such a printing surface sheet in adjusted and tautened relation upon said support, usually a rigid cylinder of metal or other suitable material, such as wood.

For simplicity, the invention is disclosed as applied to a single impression embodiment of the invention and one wherein the invention is arranged to simultaneously print a number of containers of the same size or dissimilar sizes, and for the same or different purchasers.

The full nature of the invention will be understood from the accompanying drawing and the following description and claims:

In the drawing,

Fig. 1 is a perspective view of a printing plate embodying the invention.

Fig. 2 is an enlarged sectional view of one form of enlarged end anchorage upon such a plate.

Fig. 3 is a side elevation of one form of printing cylinder embodied in the invention.

Fig. 4 is an enlarged sectional View of two adjacent dissimilar anchorages for plate anchorage.

Fig. 5 is a side elevation of one form of plate tension retaining lock.

Fig. 6 is a developed plan of a printing cylinder with a plurality of printing plates of the same and dissimilar size thereon. 1

It is the purpose of this invention to provide a quick printing surface on the printing press which will result in a considerable decrease in the amount of down time required for a printing surface sheet change on the printing machine. The printing surface sheet would carry the center line in both directions and when properly positioned on the cylinder, in relation to the center lines of the cylinder, the enlarged end 14, Fig. 1, would be inserted in the opening ll, Fig. 3, and then wrapped around the cylinder, placing the remaining end section M,

in the recess 23, and the cylinder 2|. would.

then be rotated clockwise, locked in position and in a tautening position, with the ratchet 25 and mounted on separate printinlg surface sheets and it is only necessary, in this case, after the completion of one job, to loosen the sheet or sheets, move it or them to the proper position for the next job, lock it or them up and start production.

The standard printing machines for container manufacture are designed to permit quick adjustment of the timing of two or more cylinders and, therefore, it is only necessary to shift the printing dies on the cylinder in the end-to-end direction to meet the requirements-of different size containers or blanks to be printed, that require only a change in the spacing of the blanks in the end-to-end direction of the printing cylinder.

The principal advantages of this invention are the reduction in down time of costly presses, accurate positioning of dies and an increase in the life of the dies because of the elimination of tacking when wood cylinders are used, or clamping or screwing in the case of metal faced cylinders.

For a better understanding of the invention, the present practices are briefly reviewed as follows: 7

The first operation in the manufacture of corrugated or solid fibre containers, in the case of corrugated containers is that of corrugating the center member and then applying the liners. And, in the case of solid fibre board is that of laminating plies of paperboard to develop the proper caliper. This operation sometimes includes the slitting of the mill run widths to the desired container'blank widths and the addition of the scores which run in that direction.

This first operation is one that generally permits rather uniform production in lineal feet per hour, regardless of the number of orders included in an hours run. However, when We get down to the final blanking and printing operation, the machine preparation or setup is quite a variable factor. In the corrugated industry, costly printing presses or combination printers andfslotters are out of operation from 40% to 60% setups on these machines. It is, therefore, very importantthat ways and means be developed to reduce the down time on printers or printing and slotting equipment, so as to level out the flow of production throughout the container plant.

A relatively large percent of the rubber dies or stamps inherently warp and it is extremely difiicult, unless the same are individually mounted with extreme care, to insure that unifornr and perfect work is obtained from the die which has warped.

The present invention contemplates the use of rubber dies or stamps which, whether warped or not, can be properly mounted upon a flexible, inextensible sheet arrangement so that when the flexible, inextensible arrangement is mounted upon the supporting printing cylinder, the aforesaid warpage of the die or stamp is eliminated.

In Fig. 1 of the drawing, It indicates a sheet of kraft paper, which is relatively nonexpansible although it is very flexible. A length ofkraft paper for a sheet developed for practically wrapping the entire face of a 15-inch diameter cylinder or the like is relatively inextensible.

To this sheet III, there is adhesively secured the several rubber dies or stamps II. As previously stated, these rubber dies or stamps are subject to buckling or warping but it is quite obvious that they may be accurately positioned on the sheet and adhesively secured thereto as at I2, see Fig. 2, and held under pressure, letter press fashion, in the predetermined position on said make-ready sheet until the entire adjacent faces of the sheet and die or stamp are adhesively secured together with the die in flattened relation. This eliminates the warping in the die or stamp but only temporarily. Immediately upon release of the pressure, the warping efiect returns to the die or stamp, and the die or stamp and that mounting portion of the sheet warps accordingly. Each end of the sheet In is enlarged as shown clearly in Fig. 1.

In Fig. 2, one method of sheet end enlargement is illustrated. Herein, there is secured an anchor strip I3 and the kraft paper I0, as indicated at I4, is wrapped therearound one or more times. Each of the two ends of the sheet II] is thus formed with enlargements in this or any other equivalent character. The strip I3 may comprise a wood member or may be a member of solid fibre stock and if of the latter character, may be formed from trimmings obtained as a result of the formation of solid fibre containers to which this invention also is readily applicable for the printing thereof. It is to be understood that the ends are so formed that they are truly parallel insofar as it ispossible to make them parallel.

Reference now will be had to Fig. 3. In said figure, the numeral I5 indicates conventionally a shaft which supports a printing drum or cylinder I6, the method of support being not illustrated. The peripheral surface of this cylinder is wood and is relatively rigid. Formed therein there is a recess I1, the detail arrangement of which is shown most clearly in Fig. 4. This recess is of suflicient depth to provide an overhanging tongue portion IB and the portion of the recess below the tongue is at least equal to the width of the enlarged end I4 and the width of the throat I9 of said recess adjacent the tongue is at least equal to the thickness of the end I4 so that one enlarged end of the printing surface sheet, previously described, may be radially seated in said recess I! and the relatively inextensible but flexible sheet wrapped around the cylinder I6 until the other end is positioned adjacent the anchored end. When longitudinal or end seating, as distinguished from radial or surface seating, is employed, the throat I9 need only be large enough to pass the thickness of said sheet.

As hereinafter pointed out, the sheet need not wrap entirely around the cylinder. Also, as hereinafter described, recess II utilized need not be positioned adjacent the adjustable anchorage hereinafter more particularly described.

The container industry has standardized on very few diameters of printing cylinders and the majority of container plants do not have more than two diameter cylinders to deal with. Therefore, it is a very simple matter to position the locking recesses I! and 23, so that a printing surface sheet made up to fit a small cylinder Adjacent the anchoring recess, there is provided in the cylinder a tangential cylindrical bore and mounted and rotatable therein is a similar cylinder 2|. The cylinder 3 has a throat 22 communicating with the bore and the width of this throat is appreciably greater than the width of the other end M of the printing surface sheet. for radial seating. The tautening cylinder 2| includes a recess 23, preferably rectangular in form as shown, the depth thereof being at least equal to the thickness of the anchoring end I4 and the width thereof being at least equal to the width of the anchoring end I4.

The free end I l, previously mentioned, of the printing cylinder encircling printing surface sheet, then is seated in the recess 23 when the latter registers with the throat 22. Following such seating, the printing surface sheet will bag about the cylinder IS. The cylinder 2| then is rotated clockwise-see Fig. 4-and this slack or bag is taken up and as it is taken up, the recess seated end I4 is carried by said recess 23 clockwise and the body portion ID of the make-ready sheet immediately adjacent that end passes between the inner wall of the bore 20 and the outer surface of the cylinder 2|. The end I4 is also included within bore 20.

This rotation is effected by means of a detachable handcrank, not shown, associated with either squared end extension 24 of a shaft which mounts the cylinder 2| in cylinder I6. Referring to Fig. 5, it will be noted that one extension of the aforesaid tautening arrangement mounts a ratchet 25 and associated therewith is a locking pawl or dog 26 pivotally supported at 2'! onthe adjacent end of the cylinder I6. The cylinder 2| may be nested in cylinder IS, the bore 20 having a shaft receiving closure.

A spring 28 anchored as at 29 upon the cylinder |G normally constrains the pawl into ratchet engagement. Thus, when the cylinder 2| is rotated clockwise-see Fig. 4-the ratchet 25 freely passes or moves relative to the pawl but ratchet return movement is preventedby reason of the ratchet and pawl locking arrangement, The force of this spring 28 is such that centrifugal force upon the pawl is insufficient to disengage the pawl from looking arrangement with the ratchet. However, the pawl may be disengaged from the ratchet by manually moving said pawl therefrom when the ratchet has been advanced an amount in the tautening direction sufficient to permit the end of the pawl to clear the adjacent ratchet tooth for printing surface sheet release from the supporting cylinder.

It will be obvious that the printing surface sheet can be very expeditiously prepared and of materials of relatively low cost and which will have a length of life quite suflicient for the commercial purpose to which the invention is applied, since there is but little wear on the sheet other than on the dies incident to the printing operation.

In the tautening action of this flexible, relatively inextensible printing surface sheet, it will be quite clear that initially the aforesaid sag or slack will be taken up and then the paper printing surface sheet arrangement will be caused to engage intimately throughout its area the adjacent supporting area of the cylinder Hi. In this action, the warping of the dies, previously mentioned, which warping is carried through to the paper, is eliminated so that the dies when the printing surface sheet structure is mounted in tautened relation on the cylinder, function as if there were no warping in said dies or sheet.

For extending the range of accommodation of the invention and to eliminate the necessity of having all of the printing surface sheet structures of like length, the cylinder |6 may have included therein other anchoring slots suitably spaced apart. Thus, the work, which is on a very small printed area or form, would be printed by a printing surface sheet that would have its nonadjustable, anchored end seated in the slot closest to the adjustable anchorage and offset therefrom in a counter-clockwise direction and other printing surface sheets of greater length but less than the full length equal to cylinder peripheral length, would be seated in intermediate slots ll, of which two are illustrated by way of example, in similar direction.

As shown clearly in Fig. 6, it is quite clear that when the printing plate structures are made to have predetermined lengths, and since they are substantially inextensible, that printing of large and small size boxes may be effected at the same time, it being understood that one rotation of the printing roll secures one impression. In Fig. 6 there is a developed length representation of two printing surface sheets of the same length and a printing surface sheet of a shorter length. All, however, are tautened and tensioned simultaneously by the same tautening and tensioning device.

It will be obvious that the structure disclosed is capable of printing a container blank the full width of the cylinder or of a lesser width and that the printing surface sheet may be adjusted longitudinally of the axis of the printing cylinder.

The gist of the invention, it will be apparent, resides in the fact that the mounting portion I0 of the printing surface sheet structure is substantially inextensible and since this can be of kraft paper, the investment in printing surface sheet structures is infinitesimal if the rubber die portions be excluded.

Furthermore, after many runs, the printing surface sheet structure may require renewal, which is effected by merely removing the dies II and replacing the same on a new mounting portion |0-|3-|4. These printing surface sheets |U|3|4 without dies may be fabricated and held in stock, the lengths thereof being those corresponding to the arcuate distances between the tautening arrangement and the several anchoring slots.

It will also be obvious that the make-ready period cost can be materially reduced because the make-ready operator can prepare other printing surface sheet structures by mounting dies thereon while other runs are being made and upon completion of such runs, the newly fabricated printing surface sheet structure, or structures, can be substituted in short order for those previously employed.

It is to be understood that the details of construction shown in Figs. 2 to 5, inclusive, and the exemplification of a multiple embodiment of the basic invention shown in Fig. 6 is given by way of example only.

It is to be understood, also, that certain major portions of the printing copy often are common to various items of a customers containers, the principal differences being in minor plate changes or changes covering contents, model numbers and the like.

When the supporting cylinder is of wood, after the make-ready sheet has been applied, the brand stamnmay be tacked to the cylinder through the make-ready.. sheet. Upon completion of that brand order, the brand stamp or 'die may be quickly removed from cylinderand printing surface sheet, and another brand stamp applied. in like manner, and thesecond brand containers run.

A full line of brand containers of like size can thusbe run with a-minimum of down time. Thereafter, for another size of container, if the printing dies.- and printing surface sheets are laid'out properly, the. same may be properly spaced apart by shifting the sheets closer together or farther apart or shifting the dies and the several brand runs repeated without requiring removal of the printing surface sheets from the roll, provided that the brand dies have not been tacked to the cylinder. If tacked, these dies must be removed and retacked when the sheets are readjusted.

. By referring to Fig. 3; it will be noted that adjacent cylinder [6 is pressure cylinder B, and therebetween is the gap A. Cylinder B is adjustable toward and away from cylinder l6 in accordance with stock utilized for container formation. Both cylinders, however, have the same relative peripheral speeds.

Now, if the customers plates, dies or stamps are worn down, or initially are not of the usual height or. thickness, the plate is shimmed or padded out from the cylinder by spacing means such asthick and/or thin sheets as required so thatthe peripheral speeds of the pressure roll face and printing face of ,the' stamps, dies or plates are the same.

It is also to be understood that the printing roll can be adjusted angularly about its axis relative to the pressure roll. In this manner, the position of the printing stamps can be advanced or retracted so that the impression on the container blank can be properly located. This feature of adjustment, however, is common to printer-slotters but is mentioned since containers having but one variable dimension and requiring the same printing dies can be printed in successive runs by merely angularly regulating or adjusting the position of the aforesaid dies, stamps or printing plates.

A brief summary of some of the advantages of this invention, including some mentioned hereinbefore, are as follows: 7

' A. Continuity of flow of product;

B. Reduction in the wear and tear on printing plates;

C. Ability to use warped or buckled plates;

D. Definite reduction'in the time required for removing the printing plates from the cylinders;

E. Simple mechanical means for locking and tautening make-ready sheetahaving few moving parts and elimination of delicate parts which would easily become clogged with ink;

F. Locking and tautening means uses minimum area of'the cylinder;

G. In the case of wooden cylinders, we definitely reduce the wear and mutilation of the cylinders because of the elimination of the majority of the tacks required inthe old process. This results in maintaining a more nearly perfect cylinder face which is necessary for high grade certain minor plates at the end of one run and tacking substitute plates into position for the next job;

I. This type of printing surface sheet can be attached to the cylinder and removed from the cylinder many times without any apparent depreciation or damage to the printing surface sheet. In the former method, the tacking through the printing surface sheet caused considerable damage to it, particularly at the top and bottom edges and, consequently, shortened its life; 7

J; This method permits quick and accurate positioning on the cylinder, which isparticularly advantageous on close register work;

K. This printing surface sheet permits the calipering of the printing plates and the use of shims, or padding, under the lower plate on the make-up table and eliminates this costly item of down-time on the printing press.

L. This make-ready method permits mounting two or more printing surface sheets on the same cylinder for jobs requiring practically the same dies with only a change of positioning or a change in centers in the end-to-end direction of the cylinder.

While the invention has been illustrated and described in great detail in the drawing and foregoing description, the same is to be considered as illustrative and not restrictive.

The several modifications described herein, as well as others which will readily suggest themselves to persons skilled in this art, all are considered to be within the broad scope of the invention, reference being had to the appended claims.

The invention claimed is:

1. A tautening and adjustable anchorage for relatively inextensible flexible printing surface sheets including an elongated cylindrical bore in a printing cylinder and parallel to the axis thereof and adjacent the cylinder periphery and having a throat of appreciable arcuate width coincident with the projected continuation of the periphery, an elongated cylindrical support member rotatably mounted in said bore and including an elongated recess in the support surface and parallel to the axis of the support, a relatively inextensible, flexible printing sheet having an enlarged end freely and radially seatable in said recess when the latter registers with the throat, said bore receivable member upon rotation in the bore simultaneously locking the printing surface sheet enlarged end in the recess by bore wall cooperation and tautening the sheet on the cylinder, and means associated with the bore' receivable longitudinally recessed member for normally holding the same in rotated relation with the recess ofi'set anguluarly from the throat for recess closure and for printing surface sheet anchorage retention tautening. v 2. A tautening and adjustable anchorage for relatively inextensible flexible printing surface sheets including an elongated cylindrical bore in a printing cylinder and parallel to the axis-thereof and adjacent the cylinder periphery and having athroat of appreciable arcuate width coincident with the projected continuation of the periphery, an elongated cylindrical support member rotatably mounted in said bore and including an elongated recess in the support surface and parallel to'the axis of the support, a relatively inextensible, flexible printing sheet having an enlarged end freely and radially seatable in said recess-when the latter registers with the throat, saidbore receivable member upon rotation in the and printing surface sheet bore simultaneously locking the printing surface sheet enlarged end in the recess by bore wall cooperation and tautening the sheet on the cylinder, means associated with the bore receivable longitudinally recessed member for normally holding the same in rotated relation with the recess offset angularly from the throat for recess closure and for printing surface sheet anchorage retention and printing surface sheet tautening, the printing surface sheet having an opposite end similarly enlarged, the cylindner having a longitudinally directed surface groove therein peripherally spaced from the throat slightly less than the length of the sheet between enlarged ends, the groove having a throat at the cylinder periphery through which the opposite end enlargement of the sheet is readily passable, and a projection extending into the second-mentioned throat adjacent the cylinder periphery and arranged for sheet opposite end enlargement retention for tautening and positioning of the sheet upon the cylinder.

3. A combination as defined by claim 2, characterized by the cylinder surface including a plurality of identical grooves, the projections therein being similarly directed, one of the grooves being positioned immediately adjacent the bore.

4. A combination as defined by claim 3, characterized by the width of the recess exceeding its depth and the depth of the groove exceeding its width, the sheets enlarged ends being rectangular in cross-section, the recess receivable end being flatwise receivable and the groove receivable end being edgewise receivable.

GEORGE E. BOMBERGER. HOWARD H. NIEDERAUER.

Images