US2229133A - Apparatus for printing - Google Patents

Description

Jan. 21, 1941. 1. M. SANDS 2,229,133

APPARATUS FOR PRINTING Filed Dec. 27, 1938 XAZ COWI'DVNA uuuuuuuuuuuu I 1N VENT OR.

LEO f7 SAND.

ATTORNEYS BY paw, ,y/Mx, 7 71m of them with respect to the cylinder.

Patented Jan. 21, 1941 UNITED STATES 2,229,133 APPARATUS roa ram'rmc Leo M. Sands, Norwalk, Ohio,

- Printing Comp y, Nor-walk, Ohio, a

Rotary corporation of Ohio assignor to The Application December 27, 1938, Serial No. 247,819

1 Claim.

This invention relates to printing apparatus and particularly to means for enabling the use of rubber plates in a simple and expeditious mam siderable time for completion of a satisfactory job.

An effort has been made to improve the qual- 20 ity of the printing produced by metallic platesand to this end, rubber plates have been devised, but so far as I know no adequately satisfactory means has been available for aligning the rubber plates and for preventing slippage The problem of slippage is important, particularly in connection with the manufacture of printed forms that are numbered in numerical sequence.

To align the metallic plates the practice has 30 been to use-attachments known=as saddles but it was found that these did not work satisfactorily with rubber plates. Accordingly. although rubber plates produced a better qualityof printing nevertheless, dueto the difliculty of obtaiii 35 ing satisfactory adjustment, the make-ready time was not shortened.-

The present invention has for its objects the retention of the advantages of rubber plates, and at the same time the elimination of the ob- 40 jection to the excessive time required for makeready work. The present invention accomplishes the desired results, therefore, without the need for saddles that have heretofore been used in this art and in addition has reduced the make- 45 ready time to. a great extent, in fact, in some cases to the extent of about ninety percent.

Referring now to the drawing, F 1 is a view showing a printing cylinder made in accordance with my invention and having rubber plates C thereon; Fig. 2 is a section taken on the line 2-2 in Fig. 1 on an enlarged scale and Fig. 3

is a section taken on the line 3-3 in Fig. 2.

My invention is shown. in connectionwith rubber plates in which have abacking of ad- 55 hesive material for attachment to the printing upon application of the 1 ing groove l2 20 with one of the peripheral grooves i5.

. Additionally,

cylindendesighated in general at H. The cylinder is provided with means for aligning the plates with respect to each other and for retaining them against movement with respect to to the cylinder after they have been positioned I thereon. In the preferred arrangement the cylinder has parallel lines in the form of narrow grooves l2 extending in an axial direction along the plate receiving surface and has peripheral lines in the form of deep grooves 15, preferably at regularly spaced intervals extending peripherally of the cylinder and throughout the length thereof. a

The peripheral grooves, by receiving some of the adhesive material, provides for greater ad hesion between the plate and the surface of 'thecylinder'and thereby operate to hold the plate against movement upon the cylinder. The grooves also serve to align a longitudinal edge of the plate with. respect to the cylinder 20 while the axially extending markings or grooves I! provide a means for aligning one end edge 2| of the plate.

The adhesive material which has been found to be satisfactory is what is known in the trade as a permanently tacky adhesive which will cause immediate adherence of the plate to the cylinder plate thereto.

' In practice the rubber plates are provided with V a backing of adhesive material of such consistency that the plate can readily be removed at the completion of the printing operation; Thus to make the press ready, it is only necessary to align one end as at 2| upon an axially extendand to align a longitudinal edge After the plates are aligned on the cylinder, they are pressed against the surface thereof and as a result, a rigid connection is made between the plates and the cylinder. As contact is 49 made between the printing cylinder and the pressure rolls, the plates are more firmly pressed into engagement with the cylinder, and the force thus applied causes some of the adhesive to enter the grooves, thus more firmly holding the plates upon the cylinder. This effectively prevents hifting and enables numbered forms to be printed without the danger of shifting and without the resulting destruction of the desired sequence. 50

An important advantage of the present invention is the fact that the rubber plates can be put into accurate position the first time, thus reducing the make-ready time to a minimum.

by making the plates of uniform as vals thereon, some of said lines comprising grooves, and a soft rubber printing plate, having a backing of permanently tacky adhesive material, mounted on the cylinder in a position to bridge some of said grooves which thus re ceive some of the adhesive, whereby under rolling contact the adhesive material is forced into the grooves to prevent the plate from shifting with reference to the cylinder.

LEO M. SANDS.

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