US2334820A - Printing press - Google Patents

Description

Nov. 23, 1943. J. HAWLEY 2,334,820

PRINTING PRESS Filed Sept. 30, 1940 Patented Nov. 23, 1943 iJNl'iED STATES PATENT 'QFFECE PRENTING PRESS 7 John F. Hawley, Riverside, Ill. I

Application September 30, 1940, Serial No. 358,979

2 Claims.

This invention relates to a printing press, and more particularly to a multhcolor printing press.

It has heretofore been customary in multicolor printing presses to employ a plurality of form inking rollers having composition surfaces for bringing the ink to the printing plates, which are carried by the printing rolls. It has also been customary to employ metal printing plates in combination with the composition form inking rollers.

One of the disadvantages arising from such use of metal printing plates and composition form inking rollers is the relatively short life of the composition form inking rollers and plates. The composition form inking rollers are also relatively sensitive to changes in atmospheric conditions, such as the relative humidity, and do not always give satisfactory results.

According to my present invention,resilient printing plates, preferably of rubber or a rubber composition, are used in place of the former metal printing plates, and metal form inking rollers are employed in place of the composition form inking rollers. I find that one or two form inking rollers, or only a few form inking rollers, to each printing press roll gives better results than the larger number of composition form inking rollers heretofore used with each printing roll. Furthermore, the metal form inking rollers have practically an indefinite life of usefulness and are therefore much less expensive in the long run than composition form inking rollers.

It is therefore an important object of this invention to provide a printing press in which the printing rolls carry resilient printing plates, such as plates formed of rubber, rubber composition or the like, and in which the form'inking rollers associated with the printing rolls are provided with rigid metal surfaces for transferring the ink to the resilient printing plates.

It is a further important object of this invention to provide an arrangement of printing rolls and cooperating form inking rollers wherein the form inking rollers bear directly against the printing rolls and are positively driven by means of gears carried by the printing rolls and form inking rollers.

Figure 1 is an end elevational view, with parts omitted, illustrating a printing press embodying the principles of my invention.

Figure 2 is a fragmentary top plan view of the same.

As shown on the drawing:

The reference numeral N! indicates a stationary printing press side frame on which are mounted a plurality of printing rolls ll journaled at their ends in bearings [2 carried by the side frame Iii.

On one side of the printing press, the shaft carrying the printing rolls H are provided with gears 13, which mesh with other gears It on the corresponding ends of the shafts of the usual backing rolls. Idler gears l5 serve to connect the several printing roll gears it one with another. The web of paper W is taken off a roll It and fed into the printing press in the usual manner.

In the type of printing press shown, which is a three color job, a part of the press is movable into and out of operative position. The movable part is generally indicated by the reference numeral I7 and is provided with a manually operable rack and pinion arrangement l8 for movement along side guide rails l9. Said movable part ll carries a plurality of form inking rollers 2!], which are journaled at their ends in the side walls of the press part ll. Instead of three or more form inking rolls to each printing roll,

I prefer to employ only two form inking rollers I and to provide the driven end of each of the form inking rollers with a gear 2! which meshes with a gear l3 of the corresponding printing roll. The form inking rollers are thus positively driven from the printing rolls, which in turn are driven through any suitable train of gears from the main source of power (not shown). When the movable part ii is in operative position, as illustrated in Fig. 1, the form inking rollers 23 are in bearing contact with the printing rolls that they serve.

Each of the printing rolls H is provided with raised, annular end bearing rings or flanges 23, which are preferably formed of hardened metal. The intermediate portion 39 of each roll H is cylindrical and carries one or more printing plates 24. The printing plates are preferably formed of flexible resilient material, such as rubber, rubber composition, or a lamination of fabric and rubber composition and are provided on their back with a pressure sensitive adhesive that enables the plates to be properly positioned and secured to the intermediate cylindrical surface of the printing rolls. Each printing plate 24 bears the desired printing indicia 25, the

raised surfaces of which are substantially flush with the surfaces of the annular bearing rings or flanges 23. This is accomplished by making the thickness of the printing plates through the raised printing indicia the same as the height, indicated by H, of the raised annular flanges or rings 23 above the cylindrical surface of the printing rolls.

Each of the form inking rollers 20 is made of metal and is cylindrical throughout its length. Annular end portions 26 may be made of hardened steel for bearing against the annular bearing portions 23 of the printing rolls. Each of the form inking rollers 2|] thus presents a rigid metal surface for contact with the ink receiving surfaces of the printing plates. The ink is thereby uniformly distributed from the distributor rolls (not shown) to the surfaces of the printing indicia carried by the printing plates. Vibrating rolls 2'! may optionally be used to aid in the uniform distribution of the printing ink on the surface of the form inking rollers Zil.

Owing to the fact that the form inking rollers are positively driven from the printing rolls by means of intermeshing gears I 3 and 2 I, there can be no slippage between the contacting surfaces of the form inking rollers and printing rolls, or between the ink receiving surfaces of the printing inclicia on the printing plates and the surfaces of the form inking rollers. This results in a much longer life for the plates than was previously realized and also in a more even distribution of the printing ink. The resiliency of the printing plates, of course, diminishes the likelihood of any wear on the printingjsurfaces of the form inking rollers.

In operation, a web of paper W is fed from the roll I6 through the printing press to receive the successive imprints of ink or color from the several printing plates. The printing plates are positioned in proper registration so as to give the desired multi-colored imprint on the web. The operation of multi-color printing presses is so Well known as not to require any further explanation here.

It will, of course, be understood that various details of construction may be varied through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

I claim as my invention:

1. A method of inking a flexible printing plate comprising attaching the reverse face of said plate to a cylindrical surface and kissingly contacting the highs of said plate, while the plate is so attached, with a cylindrical surface covered with a film of ink.

2. In a printing press, apparatus for inking a resilient printing plate comprising a rigid body having a cylindrical surface, means for attaching the reverse face of said plate to said surface, another rigid body having a cylindrical surface adapted to be covered with a film of ink, and means for kissingly contacting the highs of said plate while the reverse face of said plate is attached to said first surface, with said second surface adapted to be covered with a film of ink.

JOHN F. HAWLEY.

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