US1965621A - Printing plate mounting - Google Patents

Description

H. J. WARWICK PRINTING PLATE MOUNTING July 10, 1934.

Filed July 1, 1651 2 Sheets-Sheet l v gmmtov July 10, 1934. H. J. WARWICK PRINTING PLATE MOUNTING 2 Sheets-Sheet 2 Filed July 1. 1931 Patented July 10, 1934 UNITED STATES PRHNTKNG PLATE MOUNTING Howard James Warwick, Cleveland, Ohio, as-

signor to Multigraph Company, Wilmington, Del., a corporation of Delaware Application July 1, 1931', Serial No. 548,078

9 Claims.

This invention relates to means for attaching printing plates to cylinders, and is more particularly concerned with the mounting of a plate of considerable thickness, as, for instance, in an electrotype. An object of the invention is to provide means for holding such electrotype down tightly on the drum throughout its entire arcuate extent.

Considerable difficulty has been experienced in mounting electrotypes snugly on drums, especial- 1y where the electrotype extends for more than a semi-circumference, and my invention is very applicable to electrotypes of that character which are adapted to be slipped endwise over the drum when removed from its shaft.

Another object of the invention is to provide means for retaining the electrotype in its proper arcuate shape when removed from the drum, so' that it will not be sprung during storage.

I accomplish the desired result by permanently securing to the electrotype thin sheet metal straps, the ends of which are provided with tensioning means. Preferably two of these straps are employed, seating in rabbets at the extreme ends of the electrotype and permanently secured thereto by solder passing through holes in the straps and uniting with the electrotype base. Such a construction provides the electrotype with permanent fastening means, which, when the electrotype is 7 not in use, may hold it in a partly cylindrical form just slightly larger in diameter than the drum;

then, when it is desired to use the electrotype itmay be slipped endwise onto a drum having a suitable recess to receive the tensioning means; and then, by tightening the tensioning means, one

clamps the electrotype rigidly to the drum, so that it operates as a unit therewith.

My invention is illustrated in the drawings hereof and is hereinafter more fully described, and its essential novel features are summarized in the claims.

In the drawings, Fig. 1 is a vertical section through a rotary printing machine equipped with my plate mounting; Fig. 2 is a plan of the plate cylinder of the machine, with the plate mounted thereon; Fig. 3 is an enlarged cross section through the plate at its tensioning device, as indicated by the line 3-3 on Fig. 2, mounted on a jig roll; Fig. 4 is a perspective of the plate with its holding I means; Fig. 5 is a perspective of the fastening strap and its tensioning device, detached; Fig. 6 is a detail in section showing a portion of a plate cylinder, an electrotype and the fastening strap.

4 Referring first to Fig. 1, 10 indicates the vertical 5&- frame plate of a printing machine; 11 a horizontal threaded stud 42 has a flattened head 43 lying shaft mounted therein and carrying the plate cylinder hereinafter described; 12 an inking system for inking the plate, and 13 a rotaryv platen to coact with the plate and print on paper suitably fed between them.

The plate cylinder or drum, designated 20, comprises, as shown, a hollow shell extending for something less than a complete circumference and disc-like end members 21 having hubs 22 which are splined on the shaft 11. The omitted portion of the drum shell provides a recess out of the printing region for the tensioning devices of the plate mounting.

Thirty (30) indicates the printing plate which is shown as an electrotype having an arcuate extent considerably more than a semi-circumference, but less than a complete circumference. At the arcuate edges of this electrotype beyond the printing surface'ar'e formed rabbets 31. The electrotype body is made as usual with a base of comparatively soft metal of considerable thickness and a thin facing 32 of different metal, as, for instance, copper, illustrated in the exaggerated view, Fig. 6.

The fastening straps, designated 40, are thin sheet metal members, preferably steel, having a width and height preferably less than the width and depth of the rabbet, respectively. The straps thus occupy these rabbets and are well below the printing surface.. Two ends of each strap are bent inwardly, as at 41, to project toward each other'ina plane, and these ends are secured together by an adjustable tensioning device, which I will now describe.

As shown, in the drawings, the tensioning device comprises a turnbuckle having an externally threaded stud secured to one end of the strap, and an internally threaded sleeve swivelly connected to the other end of the strap. The

against the underside of the strap to which it is rigidly secured by two or more rivets 44 passing through the head and strap and preferably countersunk in each of them. A suitable block 45 is similarly secured by countersunk rivets 46 to the other end of the strap. In the free edge It is a feature of my invention to make the llll straps a permanent part of the plate so that they may not only hold it in place on the drum when it is mounted, but may retain it against distortion when it is stored. To effect this, I desire to solder the straps directly to the electrotype, and I accomplish this by making a series of openings 51 through the straps, and corresponding openings through the electrotype facing in the rabbets, and passing solder into the openings to unite the straps to the electrotype base.

I find a very convenient method of procedure is to mount the electrotype on a suitable jig roll having a diameter corresponding to the printing drum, as, for instance, the jig roll B in Fig. 3. With the electrotype on said roll, the straps are put in place, and the turnbuckles tightened to clamp the electrotype in exactly the same position it is to have on the drum. Now I pass a drill, indicated as A in Fig. 3, successively through the openings 51 to drill through the copper facing 32 of the electrotype, and then I pour molten solder 52 through the openings 51. This solder passing through the copper facing 32 autogenously unites with the base of the electrotype, which is a metal somewhat similar to the solder. The soldering studs not only pass through the steel band, but slightly spread over the top thereof, as shown in Figs. 3 and 6, and thus firmly unite the steel band to the electrotype.

An electrotype equipped with my steel bands having the tensioning devices as shown in Fig. 4, constitutes a unitary printing member which may be readily stored in a suitable container with theelectrotype only very slightly larger in internal diameter than the external diameter of the printing drum; then, whenever it is desired to use the electrotype, it is slipped endwise over the drum, the tensioning devices occupying the recesses of the drum, and rotation of the turnbuckle sleeves effects a tight clamping of the electrotype on the drum. By this means, I never vary the curvature of the electrotype an appreciable amount and the accurate printing surface thereof is maintained in perfect condition.

I claim:

1. The combination of a printing plate, a band having an intermediate region thereof permanently attached to the plate, and means for drawing together the free ends of the band.

:2. The combination of an arcuate printing plate having a recess, a band lying in the recess, means for permanently attaching the band to the base portion of the plate beneath it, and means for drawing on the respective ends of the band.

3. The combination of an arcuate printing plate having recesses adjacent its ends, a pair of metal bands lying in the recesses and having free ends, means for permanently attaching the bodies of the bands to the printing plate, and turnbuckles connecting free ends of the bands.

4. The combination of a printing plate, a band overlying the same and having openings through it, and solder passing through the openings and united to the plate.

5. The combination of an electrotype, a band extending across the same, openings through the band, registering openings through the facing metal of the electrotype, and solder occupying the openings of the band and of said facing and being autogenously united with the base of the electrotype.

6. The combination of an arcuate electrotype having rabbets at its edges, a pair of steel bands occupying the rabbets and extending a less radial height than the plate, openings through the bands, solder passing through the openingsand through the electrotype facing to the base of the electrotype at the rabbets, and turnbuckles connecting the free ends of the bands.

'7. A plate mounting, comprising the combination with a plate, of a strap having free ends, a threaded stud permanently secured to the one free end, a block permanently secured to the other free end, and an internally threaded sleeve swiveled to said block.

8. The combination of a flat metal band for a plate mounting, a threaded stud having a flattened end riveted to the band adjacent one end thereof, a block riveted to the band adjacent the other end, a pin carried by said block and having a head at its far end, and an internally threaded sleeve having a bore receiving the head and a constricted end embracing the pin beyond the head, said sleeve being internally threaded from its other'end to receive the threaded stud.

9. The combination of an arcuate printing plate, an arcuate band extending for more than a semi-circle and having its end portions free and its intermediate region permanently attached to the plate, and means for drawing together the free ends of the band.

' HOWARD JAMES WARWICK.

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