US2710564A - Carriage and holding means for printing plate shavers - Google Patents

Description

June 14, 1955 w. E. PRICE 2,710,564

CARRIAGE AND HOLDING MEANS FOR PRINTING PLATE SHAVERS Filed July 2l, 1954 2 Sheets-Sheet l June 14, 1955 W. E. PRICE CARRIAGE AND HOLDING MEANS FOR PRINTING PLATE SHAVERS Filed July 2l, 1954 www 2 Sheets-Sheet 2 fhwen'of" Wa mzf. (Price @www United States Patent Olice CARRIAGE AND HOLDING MEANS FOR PRINTING PLATE SHAVERS Wayne E. Price, Neenah, Wis. Application July 21, 1954, Serial No. 444,727

2 Claims. (Cl. 90-26) This invention relates to equipment for manufacturing printing plates and more particularly for holding and controlling an arcurate printing plate while its back surface is being shaved or ground to suitable thickness and smoothness.

There are many methods of making printing plates but substantially all require the shaving and smoothing of the backing metal. After the electroplated shell is produced from a mold or matrix it is backed by suitable backing metal for strength and thickness. This backing material may be applied by casting, pressure casting, molding or centrifugal casting. Obviously, to finish the plate for a printing press, it must be ground or shaved at the back to smooth it and to reduce it to the proper thickness. This is even true in the new laminated plates having a relatively thin backing metal or the back of the printing shell. While lathes and like are in common use for this shaving of the backing material, the holding of the plate has been a problem, particularly with arcuate rotary press plates. First, the plate is diiiicult to align with the shaver and any lateral movement of the plate during the shaving procedure will cause it to be ruined. Also, the clamps used to hold the plate are slow to set or release. One reason for all these problems is that the plates vary greatly in dimensions.

Therefore, the principal object of my invention is to provide a supporting bed and readily adjustable plate holding means for printing plate Shavers.

A further object of my invention is to provide a printing plate shaving device that permits quick adjustment for obtaining plates of different desired thicknesses.

A further object of this invention is to provide a bed holding means for printing plate shavers that will suc cessfully handle plates of various widths.

Still further objects of this invention are to provide a carriage bed for printing plate Shavers that is economical in manufacture, and durable in use.

These and other objects will be apparent to those skilled in the art.

My invention consists in the construction, arrangement and combination of the various parts of the device, whereby the objects contemplated are attained as hereinafter more fully set forth, speciiically pointed out in my claims, and illustrated in the accompanying drawings, in which:

Fig. 1 is an outer end View of my device ready for use,

Fig. 2 is an end view of a portion of my device illustrating the use of shims for controlling the thickness of the plate to be produced,

Fig. 3 is a top plan view of the carriage bed,

Fig. 4 is an enlarged cross sectional View of the lever ratchet control means taken on line 4 4 of Fig. 3, and

Fig. 5 is an enlarged longitudinal sectional View of one end of the device taken on line 5-5 of Fig. 3 and more fully illustrates its construction.

In these drawings I have used the numeral to genvsurface of the trough and the cutting tool.

erally designate the shaver having the usual rotating cut ting tool 11. Such Shavers are standard, and itis to such equipment that l use my device and which I will now describe in detail. The numeral 12 designates an arcular trough or carriage bed, substantially a half circle in cross section as shown in Fig. l. This trough is mounted on a supporting frame 13 and is longitudinally concentric with the rotating cutting tool 11. Usually, the cutting tool besides rotating will move forth and back within the trough 12 thereby planing or shaving any object held within the trough. Or, if desired, the trough may be caused to reciprocate forth and back relative to the rotating cutting tool. In either case if a curved printing plate were held within the trough, the cutting tool could shave the back of the plate. The thickness of the iinished plate would be that of the distance between the Obviously to obtain a thinner plate, the cutting tool could not be lowered relative to the trough bed inasmuch as the diameter of both the trough inside surface and the cutting tool are xed and are relative to each other. Therefore, I use a shim sheet or like 14 under a printing plate 15 as shown in Fig. 2. The thickness of a shim 14 or shims will thus determine the thickness of printing plate desired. On the left side of the trough are a plurality of hydraulically operated plate holding fingers 16. These fingers, when power lowered extend over and slightly beyond the left marginal edge of the trough to engage the left marginal edge of an arcuate printing plate as shown in Fig. l. The fingers only partially extend over the edges of the plate so that they will not be engaged by the cutting tool. However, when they are in lowered position they will prevent the rotation of the plate to the left in the trough. Also by being a plurality they will successfully engage all along the left edge of the plate even though the plate edge is uneven. Furthermore, they` will prevent any twisting or canting of the plate in thev trough. To remove the plate from the trough the hydraulically actuated lingers are released from their lowered holding action. The lingers may be operated in unison, or may each have a separate manually operated valve. The numeral 17 designates a rotatably mounted shaft along the outer left side of the trough. The numeral 18 designates a shaft mounted on the outer right forward side of the trough. The numeral 19 designates a shaft mounted on the right rear side of the trough. The numerals 2i) and 21 designate two sprocket wheels on the forward ends of the two shafts 17 and 18, respectively. The numerals 22 and 23 designate two sprocket wheels on the rear ends of the two shafts 17 and 19, respectively. The numeral 24 designates an endless chain embracing the sprocket wheels 20 and 21. This chain has its center lengths extending under the forward end portion of the trough. The numeral 25 designates a similar chain embracing the sprocket wheels 22 and 23 and having its lengths extending under the rear end portion of the troughs. Each chain has its lower center length held apart from its upper center length by an idler wheel 26. The numeral 27 designates an elongated bar, curved in cross section and extending longitudinally within and on the inside surface of the trough as shown in Fig. 3. This bar extends beyond each end of the trough and detachably on each of its two ends is a downwardly extending L-shaped hook 28. These hook members or guides extend under the end portions of the trough as shown in Fig. 5. The forward lug hook member 28 is imposed in the upper center length of the chain 24 and the rear lug hook member is imposed in the upper center length of the chain 25. On the outside of each end portion of the trough and inside the adjacent lug hook is a raised track 29. These two tracks extend under and around the bottom of the trough and provide a track Patented ,lune 14, 1955v guide for the two chains 24 and 25, respectively. By this' arrangement of parts whenV the shaft 17 is rotated the two chains will be rotated and the bar 27 will be moved transversely of the longitudinal length of the trough. Thus if a plate is on the trough surface and to the left of the bar, the bar will engage the right marginal edge of the printing plate and if the fingers 16 are in effective lowered positions the bar will hold the right side of the plate. Thus the fingers act as a stop in one direction to the plate, and the bar acts as a stop in the other direction. This tightening and ctamping of the plate between the two fingers and bar is obtained by rotating the shaft to the left. By rotating the shaft to the right, the bar will be moved away from the plate and the plate will be released. By the bar operating in a considerable arc of the trough, various plates may be accommodated. To facilitate the manual rotation of the shaft 17 l have provided a crank handle 31A on its rear end. Any suitable shaft hoiding means may be used. In the drawings I use a releasable ratchet means. The numeral 32 designates a ratchet wheel on the shaft 17. A toggle spring loaded pawl 33 is mounted on a frame bracket for selectively engaging the teeth of the ratchet wheel. A release lever 34 is also provided. By this structure the crank may be rotated to bring and hold the bar in locked condition against the right side of the printing plate to be shaved. After the shaving process, the ratchet wheel is released and by turning the crank in the opposite direction, the iinished plate may be removed from its holding trough. before described the used and purpose of a shim 14. Obviously when such a shim or shims are used between the face of the plate and the trough, the fingers 16 are not long enough to be eiective. Therefore, l provide a linger extension 35 for each finger as shown in Fig. 2. Also the bar 27 will have to be raised accordingly and I insert a shim 36 between each hook member 28 and the bar as is also shown in Fig. 2.

Some changes may be made in the construction and arrangement of my carriage and holding means for printd ing plate Shavers without departing from the real spirit and purpose of my invention, and it is my intention to cover by my claims, any modied forms of structure or I have hereuse of mechanical equivalents which may be reasonably included within their scope.

i claim:

l. In combination, a rotating shaving tool, an arcuate trough in which said tool is capable of operating, a stop means on said trough for limiting the rotation of a print ing plate in one direction, a movable bar in said trough for limiting the rotation of a printing plate in the opposite direction, a hook member on each end of said bar extending around the end of and terminating on the underside of said trough, a rotatably mounted shaft at one side of said trough, a first and second sprocket wheel on said shaft, a third sprocket wheel, a fourth sprocket wheel, a chain embracing said rst and third sprocket wheels and secured to one of said hook members, a second chain embracing said second and fourth sprocket wheels and secured to the other hook member, a means for rotating said shaft, and a means for locking said shaft at times against rotation.

2. In combination, a rotating shaving tool, an arcuate trough in which said tool is capable of operating, a stop means on said trough for limiting the rotation of a printing plate in one direction, a movable bar in said trough for limiting the rotation of a printing plate in the opposite direction, a hook member on each end of said bar extending around the end of and terminating on the underside of said trough, a rotatably mounted shaft at one side of said trough, a first and second sprocket wheel on said shaft, a third sprocket wheel, a fourth sprocket wheel, a chain embracing said first and third sprocket wheels and secured to one of said hook members, a second chain embracing said second and fourth sprocket wheels and secured to the other hook member, a means for rotating said shaft, a means for locking said shaft at times against rotation, and track means on the outer underside of said trough for said two chains.

References Cited inthe tile of this patent UNITED STATES PATENTS 1,907,588 Rupp May 9, 1933 2,168,548 Wood Aug. 8, 1939 2,672,772 Bungay Mar. 23, 1954

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