US2894454A - Method of preregistering printing plates in multicolor printing - Google Patents

Description

Jul 14, 1959 S. K. HILLIER- METHOD OF PREIREGISTERING PRINTING PLATE IN MULTICOLOR PRINTING Filed Aug. 1, 1957 I INVENTOR STANLEY KHILLIER ATTYS July 14, 1959 s. K. H LIER METHOD OF PREREGISTE NG PRIN 2,894,454 TING PLATES IN MULTICOLOR PRINTING 2 Sheets-Sheet 2 Filed Aug. 1, 1957 R Wm TL H K N IY E L N m s United States Patent METHOD OF PREREGISTERING PRINTING PLATES 1N MULTICOLOR PRINTING Stanley K. Hillier, Chicago, 111., assignor to W. F. Hall Printing Company, Chicago, 111., a corporation of Illinors Application August 1, 1957, Serial No. 675,646

4 Claims. (Cl. 101-211) This invention relates to improvements in a method of preregistering multicolor printing plates and refers particularly to a method of preregistering said plates away from the printing press whereby the time employed in registering the printing plates is not exacted at the expense of a shut down printing press.

The register of single or multiple color printing plates comprises the correlation of several separate relationships. For instance:

(a) The colors of each page if multicolored have to fit correctly into each other.

(b) The single or multicolored printed matter that results has to be in a correct space relationship to the folded page, i.e., margins have to be identical and of predetermined widths. r

(c) The printed matter has to back up correctly, i.e., printed matter and folio numbers on one side of a page must register precisely with the printed matter or folios on the reverse side of the sheet or page.

In most instances registry of multicolor printing plates has heretofore been done on the printing press itself and is substantially a cut and try operation, requiring great skill and experience on the part of the operator and requiring the press to be shut down for an excessive period of time. Other expedients have been employed involving optical devices, removable bars, or pins etc. which have been intended to facilitate the operators task upon the press but such expedients have proven unsatisfactory.

In the present invention, With the exception of a minor preliminary conditioning of the press rolls, performed but once, the operation of registering the multicolor plates for color register, page or position register, back up register (including shrinkage and skiving allowances) is all performed away from the press, saving the long periods of shut down time heretofore required and making substantial savings in the amount of paper required for proving registration.

Among the advantages in addition to the fact that the whole of the register marking etc. may be done away from the printing press are: the method requires no marks or holes or lines in the original engravings or cuts; does not require that the printing plate edges have a definite space relationship to the printed design or as is termed in the art, beveled to register; will use plates of irregular size and shape, that is, color plates need only be the area necessary for that color; locates the plate with a tongue and groove arrangement which enables, even with spirally grooved plate cylinders, the plate to be moved and always have one marking slot appearing in the solid section of the cylinder in both coordinate directions; enables a replacement plate to be register marked away from the press so that when brought to the press, it will match with the one it replaces; enables a visual check to be made of the fit of each color plate to the other in its color set before it is placed on the press cylinder; where oversize plates fit close together, it enables a visual check and correction, if necessary, to be ICE made for clip or hook room before the plates are set on the press cylinders; and is extremely flexible and timesaving in that it does not require the ruling of a master sheet or layout each time the same job is rerun, as for instance, in weekly issues of the same or similar sized magazine.

These and other objects and advantages of the present invention will be more apparent from the accompanying drawings and following detailed description.

In the drawings,

Fig. 1 is a front elevational view of a conventional spirally grooved press cylinder provided with datum lines employed in the present process.

Fig. 2 is a diagrammatic end view of the cylinder particularly illustrating the arcuate relationship of the axial datum lines.

Fig. 3 is a face view of a layout sheet prepared as a development of the press cylinder surface.

Fig. 4 is an enlarged view of a portion of the layout sheet with a transparent proof sheet superimposed upon a plate location on the layout sheet.

Fig. 5 is a top plan view of a marking fixture, showing a transparent proof sheet positioned thereon.

Fig. 6 is a plan view of an aligning fixture for aligning a printing plate with the transparent proof sheet.

Fig. 7 is a view similar to Fig. 6 illustrating the notched printing plate.

Fig. 8 is an end view of a notched printing plate illustrating particularly the upset nibs produced by the notching tool.

Fig. 9 is a detailed perspective view of the head of a notching tool which may be employed to notch and upset the registering nibs.

Fig. 10 is a fragmentary elevational view of the press cylinder carrying a printing plate in aligned or registered position.

Referring in detail to the drawings, 1 indicates a conventional press cylinder of the type used in multicolor printing. In multicolor printing a plurality of such cylinders may be employed, one for each color to be printed. The cylinder 1, as are all of the cylinders employed, may be provided with a plurality of helical grooves 2 which are employed for locking the printing plates upon the cylinder surface.

Although a press cylinder having helical grooves is illustrated, it is to be understood that the present method may also be used with conventional press cylinders provided with circumferential or lateral grooves.

As a step in the present process and the only one which need be performed upon the press to use the process,

. with the exception of the actual mounting of the plates in preregistered position upon the cylinder, the cylinder surface is inscribed with a plurality of axial and circumferential relatively shallow lines 3 and 4, respectively. The axial lines or indentations 3 are disposed in pairs throughout the circumference of the cylinder and the circumferential lines or indentations 4 are also disposed in pairs along the length of the cylinder. The reason for disposing the respective lines in pairs will be hereinafter more fully described. The lines 3 and 4 are, in effect, relatively shallow indentations, as shown best in Fig. 2, the purpose of which will be hereinafter more fully described.

The lines 3 and 4 are inscribed upon all of the press cylinders employed, and although four pairs of axial lines 3 are shown and five pairs of circumferential lines 4 are shown, the number of pairs of lines is not critical and will depend upon the diameter and length of the clyinders and the size of the printing plates used.

The operation of inscribing lines 3 and 4 on the press cylinders is done but once and, hence, all of said press cylinders are thereafter conditioned to be employed with the remaining steps of the method which latter may be repeated, as desired. Hence, loss of press shut down time is substantially negligible in carrying out the present invention.

As a further step in the method of the present invention, a layout sheet 5 is employed. The layout sheet 5 is preferably a relatively thin sheet of zinc or other stable material which may be readily inscribed by an awl or other pointed marking tool. The layout sheet is so dimensioned as to be equal to the developed surface of the cylinder 1. The sheet 5 is placed upon a table or other supporting surface and an operator proceeds to draw, preferably by a marking tool, predetermined key lines which will be hereinafter described.

The key lines inscribed upon the layout sheet 5 cornprise the defining lines 6 of the areas of each plate occupied by the printing; the bleed lines 7 where, in some instances, the printed material is carried to the edges of the pages; the position of the packing cylinder slots, etc. Initially, lines, corresponding to lines 3 and 4 on the cylinder 1, are located but not inscribed upon the face of the layout sheet. These lines are indicated by the dotted trace lines 3 and 4', respectively, in Fig. 3. However, when lines 3 and 4 are located, the distances between adjacent pairs thereof are bisected and lines 8 and 9 are inscribed upon the layout sheet. The areas defined by the lines 6, including bleed allowances where necessary, are inscribed relative to the lines 8 and 9 which constitute coordinate center lines for the printing plates which are subsequently mounted upon the press cylinder, as will be hereinafter more fully described.

When completed, the layout sheet 5 will be a substantial duplicate of the press cylinder developed surface with substantially the exact location of the plates indicated. Of course, in inscribing the layout sheet the nature of the signatures must be taken into consideration, e.g. a layout for a 40-page magazine to be folded as 2-16s and l8 page signature would be spaced differently than, for example, a layout to deliver as ten 4-page signatures. A layout once made, is permanent and may be used repeatedly for the same folder combination, thus saving much time and insuring exact duplication of page po sitions from job to job.

A transparent proof 10 (Fig. 4) is made upon a conventional proof press, of each key plate, usually the black plate, for each of the inscribed pages upon the layout sheet 5. Each respective proof 10, carrying printed material 11, is positioned over each page area upon the layout sheet and the margins of the printed area of the proof are aligned with the lines 6 and 7. When such alignment is secured, the lines 8 and 9 constitute page center lines and marks 12 and 13 are made upon the proof which indicate the coordinate center lines thereof. If desired, marks 12 and 13' may also be made upon the proof, but marks 12 and 13, when used with a suitable marking fixture, to be hereinafter described, are all that will be found necessary.

Each proof may then be positioned upon a marking fixture 14 (Fig. 5) which may comprise a flat metal plate having inscribed thereon coordinate lines 15 and 16. A punch 17 may be positioned upon the plate fixture adjacent each end of the line 16, the male member of each punch being bisected by the line 16.

The proof 10, carrying the marks 12 and 13 and, if desired, marks 12' and 13, may be positioned upon the fixture plate 14 and marks 12 and 13 may be brought into coincidence with lines 15 and 16, respectively. Of course, marks 12' and 13', if used, will also be brought into coincidence with lines 15 and 16. With the proof in this position, the punches 17 may be manipulated to punch opposite holes 18 in the proof. These holes will lie along one of the center lines of the proof, namely, that center line which corresponds with line- 9 on the layout. sheet 5.

The proof 10, provided with the holes 18 is now geometrically related to the layout sheet 5 in substantially the same manner as the corresponding printing plate is to be related to the press cylinder 1. The next step in the process, therefore, comprises geometrically relating the proof 10 tothe printing plate so that said plate will occupy the desired registered position upon the press cylinder.

For convenience in carrying out the next step in the method, a fixture 19 may be employed. The fixture 19' is cylindrical in shape, having a radius of curvature substantially equal to that of the press cylinder 1. The face of the cylindrical fixture 19 is provided with two spaced longitudinal slots 20 which are coextensive in length with the fixture. The distance between the axial center lines of each of the slots from each other is equal to the spacing of each companion pair of lines 3 on the press cylinder 1.

The cylindrical fixture 19 is also provided with a pair of spaced circumferential slots 21 which may extend about over the arcuate surface of the fixture. The spacing of the axial center lines of the slots 21 from each other is equal to the spacing of companion pairs of lines 4 on the press cylinder 1.

The f xture 19 carries spaced annular bands 22 which bridge the slots 29 adjacent each end of the fixture, and each band carries a pin 23 spaced axially from each other. The center lines of the pins 23 are midway between the axial center lines of the opposite slots 20, and said pins are axially spaced from each other equal to the spacing of the punched holes 18 providedin the proof 10. Hence, the proof 10 may be positioned on the fixture 19 with the pins 23 threaded in the holes 18 of the proof. Accordingly, one center line of the proof will be disposed midway between the slots 20.

However, before positioning the proof 10. on the fixture 19, a printing plate 24 is positioned on the fixture. The printing plate 24 is of conventional construction and its inner arcuate face conforms with both press cylinder 1 and fixture 19.

The fixture 19 is provided with a plurality of longitudinal slots 25 in which dogs 26 are movable positioned. The dogs 26 may be carried by screws (not shown) and may be manipulated by knobs 27, which upon being turned function. to move the dogs 26 in slots 25. The fixture 19 is also provided with slots 28 which extend transaxially of the fixture and in each slot a dog 29 is positioned for movement by the manipulation of knobs 30.

In employing the fixture 19 in carrying out the present method, the printing plate 24 is positioned on the fixture between the dogs 26 and 29. It can readily be seen that by the manipulation of the knobs 27 and 30 the plate 24 may be moved with precision in both an axial and transverse direction. The proof 10 is then positioned on the fixture over plate 24 with pins 23 in engagement with holes 18. With the proof in this fixed position, the knobs 27 and 30 are manipulated to align the plate 24 with the printed image on the proof. The plate 24 is thus oriented with respect to the center lines of the slots 20 and 21' in the same fashion as the plate is to be related to the lines 3 and 4 upon the press cylinder 1.

The next step in the present method comprises indexing or marking the plate 24 relative to the center lines of the slots 20 and 21. To accomplish this step conveni'entl y, a notching tool or chisel 31 (Fig. 9) is employed.

The notching tool or chisel 31 comprises a head 32 which is secured to a tubular handle 33. A plunger 34 is axially movable in the tubular handle and may be vibrated axially by pneumatic or hydraulic means (not shown). A guide bar 35 is mounted upon the head 32 and carries a pair of spaced brackets 36 between which a chisel holder 37 is pivotally secured. The chisel holder 37 carries a chisel blade 38 coacting with a female die 38' and comprises the notching instrument per se. When the plunger 34 is operated, the chisel holder 37 oscillates between the brackets 36 and, hence the chisel 38 is moved to eifect the notching operation.

After plate 24 has been brought into registry with the image on the proof 10, the proof is removed from its position overlying the printing plate. The printing plate is then in position to be notched or indexed. Conveniently, the guide bar 35 is of a width which will permit its snug insertion in either slots 20 or slots 21 and the cutting edge of chisel 38 is disposed midway between the longitudinal edges of the guide bar 35. Hence, by the insertion of the guide bar 35 in slots 20 and 21, the printing plate 24 may be notched along the longitudinal center lines of the slots 20 and 21. As has been hereinbefore described, the distance between said center lines corresponds to the distance'between the companion pairs of lines 3 and 4 on press cylinder 1 and, hence, the plate is indexed with respect to the lines 3 and 4-.

In Fig. 8 a notched printing plate 24 is shown. Characteristic of the cutting action of chisel 38 the material along the tapered edges of the printing plate is both cut and upset to form indexing nibs 39. The nibs 39 are such as to register in section with the shallow indentations or lines 3 and 4 which assists greatly in positioning the plate upon the printing cylinder without the possibility of parallax errors.

The next step in the present method merely resides in positioning the plates 24 upon the press cylinder 1. It will be noted that the printing plate carries eight nibs 39 and, hence, in positioning the plate upon the cylinder 1 it is merely necessary to align at least four of the nibs, one on each side of the printing plate, with four of the lines 3 and 4. The printing plate in this position may he secured to the cylinder 1 in the conventional manner, using conventional clamps 40.

In view of the fact that all of the cylinders 1 of the set for producing multicolor printing are identical, the plates on each cylinder and the corresponding plates on the remaining cylinders will be respectively registered with each other through, in eifect, the common denominator of the layout sheet 5. Hence, all of the plates of the multicolor press may be registered with a minimum of stoppage of the press and, as a matter of fact, the actual operation of registry is performed without any press stoppage time at all.

Although the present method could conceivably be performed by substituting actual center lines on the cylinder 1 in place of each pair of lines 3 and 4 and notching the printing plates accordingly, the use of pairs of lines 3 and 4 is greatly preferred for the following reason. It is known that, depending upon the size of the printing plates and the number of plates carried on each cylinder 1 the plates may occupy different positions relative to the lines 3 and 4 and the grooves 2. Hence, were but four nibs formed on each plate, one on each side thereof at the coordinate center lines, it is entirely possible, were only single center lines carried by the cylinder, that one or more nibs may fall within or adjacent a groove 2 which would greatly complicate the alignment of the nibs with the center lines on the cylinder causing loss of accuracy. However, by employing pairs of linw 3 and 4 and providing correspondingly spaced nibs on the plates, the pairs of lines 3 and 4 may be so spaced as to have at least four nibs, one on each side of a plate, register with a solid portion of the cylinder. Hence, intimate mechanical registry of the plates with the cylinder always obtains, with four nibs registering and interlocking with the indentations 3 and 4.

It is to be understood that forms of mechanical apparatus and fixtures may be used in carrying out the present method other than those shown and described and, hence, it is not intended that the invention be limited to the specific means shown and described.

I claim as my invention:

1. A method of registering a set of multicolor print ing press plates including a 'key plate upon a corresponding set of substantially identical helically grooved printing cylinders for multicolor printing which comprises, inscribing substantially identical longitudinal and transverse pairs of parallel coordinate lines upon each printing cylinder, preparing a planar layout surface of one of said cylinders, said layout surface being substantially similar in dimensions to the developed surface of said cylinder, indicating trace lines on said layout surface corresponding to the lines on said cylinder, inscribing transverse and longitudinal coordinate lines on said layout surface midway between and respectively parallel to said trace lines, forming a transparent proof from said key plate, disposing the proof over said layout surface and indexing the proof in accordance with a pair of intersecting lines on said layout surface, disposing said indexed proof over each printing plate of said set and registering the printing on the proof with the printing conformations on each plate, indexing the edges of each printing plate of said set in spaced relationship to the indices on said proof, each printing plate index being spaced from a corresponding proof index a distance substantially equal to the distance of a corresponding line on said layout sheet from its corresponding trace lines, and mounting said plates on said printing cylinders with the indices on said plates in registration with the lines on said printing cylinders.

2. A method of registering a set of multicolor printing press plates including a key plate upon a corresponding set of substantially identical helically grooved printing cylinders for multicolor printing wherein each of said cylinders is inscribed with substantially identical longitudinal and transverse pairs of parallel coordinate lines, said method comprising, preparing a planar layout surface of one of said cylinders, said layout surface being substantially similar in dimensions to the developed surface of said cylinder, indicating trace lines on said lay out surface corresponding to the lines on said cylinder, inscribing transverse and longitudinal coordinate lines on said layout surface midway between and respectively parallel to said trace lines, forming a transparent proof from said key plate, disposing the proof over said layout surface and indexing the proof in accordance with a pair of intersecting lines on said layout surface, disposing said indexed proof over each printing plate of said set and registering the print on the proof with the printing conformations on each plate, indexing the edges of each printing plate of said set in spaced relationship to the indices on said proof, each printing plate index being spaced from a corresponding proof index a distance substantially equal to the distance of a corresponding line on said layout sheet from its corresponding trace lines, and mounting said plates on said printing cylinders with the indices on said plates in registration with the lines on said printing cylinders.

3. A method of registering a set of multicolor printing press plates including a key plate upon a corresponding set of substantially identical helically grooved printing cylinders, and wherein the helical grooves are interspaced with helical lands, said method comprising, inscribing substantially identical longitudinal and transverse pairs of coordinate lines upon the lands of each printing cylinder, preparing a planar layout surface of one of said cylinders, said layout surface being substantially similar in dimensions to the developed surface of said cylinder, indicating trace lines on said layout surface corresponding to the lines on said cylinder, inscribing transverse and longitudinal coordinate lines on said layout surface midway between and respectively parallel to said trace lines, forming a transparent proof from said key plate, disposing the proof over said layout surface and indexing the proof in accordance with a pair of intersecting lines on said layout surface, disposing said indexed proof over each printingplate of said set and registering the print on the proof with the printing conformations on each plate, indexing the edges of each printing plate of said set in spaced relationship to the indices on said proof, each printing plate index being spaced from a corresponding proof index a distance substantially equal to the distance of a corresponding line on said layout sheet from its corresponding trace lines, and mounting said plates on said printing cylinders with some of theindices on said plates in registration with the lines on the lands of said printing cylinders.

4-. A method of registering a set of multicolor printing press plates including a key plate upon a corresponding set of substantially identical helically grooved printing cylinders for multicolor printing wherein each of said cylinders is inscribed with substantially identical longitudinal and transverse pairs of coordinate lines, and wherein a planar layout surface is prepared of one of said cylinders, and wherein said layout surface is substantially similar in dimensions to the developed surface of said cylinder, and wherein trace lines are indicated on said layout surface corresponding to the lines on said cylinder, and wherein transverse and longitudinal coordinate lines are inscribed on said layout surface midway between and respectively parallel to said trace lines, said method comprising the 01- lowing successive steps, forming a transparentproof from the key plate, disposing the proof over said layout surface and indexing the proof in accordance with a pair of interesting lines on the layout surface, disposing said indexed proof over each printing plate of said set and registering the proof with the printing conformations on each plate, indexing the edges of each printing plate of said set in spaced relationship to the indices on said proof, each printing plate index being spaced from a corresponding proof index a distance substantially equal to the distance of a corresponding line on said layout sheet from its corresponding trace lines, and mounting said plates on said printing cylinders with the indices on said plates in registration with the lines on said printing cylinders.

References Cited in the file of this patent UNITED STATES PATENTS 1,377,511 Novotny .t.. May 10, 1921 1,498,754 Repp .Tune 24, 1924 1,839,866 Claybourn Jan. 5, 1932 1,955,933 Roesner Apr. 24, 1934 2,095,542 Claybourn Oct. 12, 1937 2,229,133 Sands Jan. 21, 1941 2,680,405 Faeber et al June 8, 1950

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