US2961770A - Gauge for obtaining registration in color printing - Google Patents

Description

Nov. 29, 1960 A L. IMSHAQG y2,961,770

GAUGE FOR OBTAINING REGISTRATION IN COLOR PRINTING Filed June 19, 1959 v 6 56D/ INVENTOR AeA/040 L. /MSHAUG ATTORNEYS United States, Patent GAUGE FOR OBTAINING REGISTRATION IN CGLOR PRINTING Arnold L. Imshaug, Brookwood, Montague, Mass.

Filed June 19, 1959, Ser. No. 821,458

1 Claim. (Cl. 33-174) The present invention relates to gauges for obtaining proper registration of a plurality of separately applied impressions used to compositely form a multi-colored print.

.In the printing art, color printing on any of the various orms of presses has been developed to a highly relined state wherein color values may be reproduced in every imaginable shade and tone. However, in order to obtain these ends it is necessary to make multiple, superposed impressions of the various prime colors which are employed.: lt isifurther necessary to have the various superposed impressions properly registered, one with another, in forder -to obtain a satisfactory composite picture or print. In the past the matter of such registration has largelybeen left to the skill of the press operator and obtained zby trial and error methods. In actual practice and particularly in the case o-fcolor impressions in news# paper work such as colored comic strips a press'operator hasheretofore merely visually checked the amount by which the matching of successive impressions may be olf-registerv and jthen made adjustments to a plate mounting structure by guesswork or estimate. AThe'object of this invention is to eliminate trial and error methods in the registration of multiple color impressions in printing operations and specically .to provideV a unique gauge of simple construction for accomplishingthe above ends.

The above and other objects as well as the novel features of the invention will be apparent from a reading of the lfollowing description of the disclosure found in the accompanying drawing and the particular novelty thereof pointed out in the appended claims.

In the drawing:

Fig. 1 is an elevation, in section, of a gauge embodying the present invention;

Fig. Zivis a fragmentary section, on an enlarged scale, taken on the line Il-II in Fig. l;

Fig. 3 is a-fragmentary view of a she-et of paper showing Loolor. register marks; v

Fig. 4 is a lfragmentary section of clamping means for the leading edge of a rotary printing plate;

Fig. 5 is a fragmentary section of clamping means for the side edge of a rotary printing plate; and

Fig. 6 is a view showing a modified embodiment of an element seen in Fig. 2.

The gauge seen in Fig. 1 comprises a cylindrical sheet metal shell 10. The top of the shell 10 is turned inwardly to provide a lip 12 and spaced therebeneath is a rolled groove 14. A lens 16 is mounted at the upper end of the shell '10 with the upper face of its peripheral margin held against the li-p 12 by a snap ring 18 seated in the groove 14. At one side of the `shell 10 is a lamp housing 20 which is open at the bottom with a standard light socket 22 mounted in its upper end. A handle 24 projects laterally from the housing 20. Electrical wires 26 pass through the handle 24 with a switch 23 being provided to control =llow of current to a light bulb 30 screwed into the socket r# 2,961,770 1C@ pafented Nov. 29, 1960 2 22. Between the housing 20 and shell 10 is a port 32 which is positioned to minimize any direct rays into the interior of the shell which might produce an undesirable glare. Y v

A tubular lens carrier 34 is telescoped into the lower end of the shell 10 and suitably secured thereto. A flange 36 engages bead 38 on the vshell 10 ,to limit this telescoping action. i p 7 A second lens 40 is mounted at the upper 'end of the carrier 34 in a manner essentially identical to the mounting of the lens 16. Thatis, the lens 40 is conned'be tween an inturned lip "42 and a snap ring 44. A port 46 is provided in carrier 34 to register with port 32 so that the interior of the shell 10 will be illuminated.

Lenses 16 and 40 are in proper optical relation with each other and wi-th any Ysurfacebrought against or in alignment with the bottom of the shell 10. The actual optical system forms no part of the present invention other than to provide a suitable magnifying means.

A reticle 48 is mounted in the bottom of the shell 10. As illustratively shown the reticle is a relatively thin transparent (eg. glass) disk which is positioned by engagement with a metal ring 50 secured to the carrier 34 and held in place by a rubber ring 52.

Referring now to Fig. 2 it will be seen -that two series of indicia lines as 54 and 56 are formed on the surface of the reticle 48. The indicia lines are devised so'as to obtain quick and accurate indication of the amount of needed adjustment of printing plates in order to obtain proper registration of successive printing impressions.

At this point, note will be taken that color printing-is carried out on many different forms of printing presses with various types of printing plates and processesQ-elg': oifset printing, lithography, etc. In anyevent, all suoli processes involve, in the printing of a oolor picture, the use of successive color plates bearing impressions of primary colors, viz. red, yellow and blue and also black or other colors. The composite of these three or more impressions will yield a composite picture incorporating all hues lof the rainbow. It is, of course, self-evident that each successive impression must be properly registered if a true reproduction of the desired colors is to be obl; tained in all areas. p

With all the variables involved in the preparation and mounting of such plates as will be understood by those skilled in the trade it lis impossible to expect the finished printing plates can be mounted in a press and A p'eijfect registration automatically obtained.' Inthe'usual set, up there is no problem in mounting the plates so ,that they will be square. However, Ithe plates will usually require adjustment longitudinally and/ or transversely lofa paper' web zbeing printed. lSuch adjustments are made byshirfting the printing plates relative to their mounting means or by otherwise obtaining a relative adjustment between the printing plate and the web being printed.

In many presses such adjustments are made by rotating threaded members. As, for example, in certain rotary presses a hand wheel adjustment is provided for moving the printing cylinder toward one side or the other of the web while another hand wheel is provided to increase or decrease the length of loop in the web between adjacent printing cylinders. In this way the printing plates may be Iadjusted longitudinally or transversely of the web to obtain proper registration between successive impressions. In such a machine one turn of each hand wheel may, for present purposes, be considered as an arbitrarily chosen standard increment of adjustment. Generally theV transverse sense, dependent on which hand wheel is rotated.

The gauge above-described is employed to obtain registration of color impressions on such presses where a standard increment of adjustment is the same in both longitudinal and transverse directions. It will be noted (.Fig. 2) that lines S4 and-56 on the reticle 48, are respectively spaced `apart the same incremental distance which distance corresponds to the standard increment of adjustment of the printing plate relative to the web, i.e. one turn of an adjustment hand wheel. The inner or zero lines 54 and 561 are disposed at right angles and form two sides of a square. The remaining lines 54 and 56 are spaced outwardly from the lines 541' and 56:' respectively.

The gauge is placed on a printed proof with the reticle overlying two diierent color impressions. The color irnpressions may be an actual portion of the picture itself or they may consist of color register marks which are oftentimes provided to visually facilitate the degree of accuracy in color registration. A typical pair of such register marks 58 and 60 are shown in Fig. 3. With the gauge overlying these register marks and with the magnication provided by the lenses 16 and 40, it is a simple matter to simultaneously determine the longitudinal and transverse adjustment necessary to obtain proper registration of the two colors. Thus, assuming that a yellow printing plate needs to be shifted, the gauge is disposed so that the lines 541' and 561' match a corner of the black register mark 58 as indicated by the phantom showing in Fig. 3. The amount of adjustment required is then readily apparent. The common indicia 62 (Fig. 2) identify the distance of each of the lines 54 and 56 from the lines 54x and 561' respectively and further facilitate the determination of the amount of adjustment required. While the indicia 62 can give actual distances, it is preferred that they represent increments of adjustment viz. one, two or three turns of -an adjustment hand wheel.

It will be appreciated, of course, that the standard increment of adjustment could be something other than one full revolution of a hand Wheel, dependent on the type of press installation that is employed.

A somewhat different approach is followed in adjusting curved printing plates in other types of rotary presses. Curved printing plates are beveled on their side edges and held in place by appropriately undercut clamps. The leading and trailing edges are square and held between clamps to position the plate longitudinally of the web. In order to adjust the curved plate relative to its mounting means, shims of varying thickness are employed. In Fig. 4, the leading edge of a curved plate 64 is shown in an adjusted position relative to clamping means 66. The adjusted position is determined by the shim 68. In Fig. 5 the side edge of the plate is shown in an adjusted position relative to clamping means 70, which position is determined by the shim 72.

It is preferable to color code the adjusting shims to identify their thickness. In the case of using shims, the standard increment of adjustment is determined by the thickness of the thinnest shim. For longitudinal adjustments the standard increment of adjustment is the actual thickness of the thinnest shim. However, in the case of transverse adjustments the standard increment is something greater than the thickness of the thinnest shim dependent on the angle on which the plate is beveled.

Fig. 6 shoWs'a modified reticle 48' which is especially adapted for obtaining color registration Where such mounting and adjusting means for curved plates are employed. Thus it will be seen that two series of indicia lines 54 and 56 are provided with the inner lines 54x" and 56x" again forming two sides of a square. The lines 54' are each spaced apart the increment for adjustment in a longitudinal direction, i.e. the thickness of the thinnest shim. The lines 56 are spaced apart the increment for adjustment in a transverse direction, i.e. a distance somewhat greater than the thickness of the thinnest shim. The lines 54' and 56' are identified by common indicia 58 radiating from the juncture of the lines 541" and 56i'. The indicia indicate the color and number of shims required to obtain the necessary adjustment indicated by the lines 54 and 56' when the reticle 48' is placed over a color register mark as indicated above.

Having thus `described the invention, what is claimed as novel and desired to be secured by Letters Patent of the United States is:

A gauge for use in establishing registration between a plurality of printed impressions made by a series of curved printing plates having beveled side edges and compositely forming a picture or the like, said gauge comprising a frame having at least one magnifying lens and a reticle mounted in vertically spaced relation therebelow at the bottom of said frame, said reticle having a series of parallel indicia lines each spaced apart one from another an incremental distance representative of standard adjustment increments of a printing plate relative to a paper web in a longitudinal direction, and a second series of parallel indicia lines each spaced apart one from another a greater distance than the said lines of the rst series and representing an incremental dis tance corresponding to standard adjustment increments of the printing plate relative to the paper web in a transverse direction, said greater spacing being dependent upon the angle of bevel on the side edges of the curved plates, the first line of each series being disposed at right angles to each other and forming two sides of a square and the remaining lines of each series being spaced outwardly from said first lines and indicia indicating the standard increment of adjustment of each line from the first line of its respective series.

References Cited in the le of this patent UNITED STATES PATENTS 2,630,631 McMullen Mar. 10, 1953

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