US3147697A - Inking cylinder - Google Patents

Description

Sept 3 1964 G. J. ZAHRADNIK 3,147,697

INKING CYLINDER Filed 001). l0, 1961 FIG.

INVENTR. George J.' Zakradmk United States Patent O 3,147,697 ING CYLINDER George I. Zahradnik, North Riverside, Ill., assignor to A. B. Dick Company, Chicago, Ill., a corporation of Illinois Filed Oct. 10, 1961, Ser. No. 144,121 4 Claims. (Cl. 101-119) This invention relates to improvements in inking cylinders such as the type of cylinders which are employed in stencil duplicating machines.

In inking cylinders which are employed in mimeograph operations, the cylinder is filled with ink which is adapted to pass through perforations in the cylinder onto an inking pad. During a duplicating cycle, the ink is adapted to pass from the pad through stencil openings in an adjacent stencil and then to a sheet to be printed.

On many occasions ink remains in the cylinder during periods of nonuse and leaking and dripping of ink has been a problem. The ink will, in some instances, seep into the ink pad and over the cylinder edges, even where the cylinder is positioned with the perforated side up. The situation is particularly noticeable where high humidity conditions are experienced.

There are other occasions where an ink pad becomes saturated with ink or Where the ink otherwise leaks from the cylinder and rolls down. It will be obvious that the presence of ink on the mechanisms below the cylinder is undesirable and it is extremely difficult to accomplish cleaning in this area of the machine.

It is, therefore, an object of this invention to provide an improved inking cylinder which is not subject to the problems of roll-down and leakage of ink.

It is a further object of this invention to provide an improved inking cylindeiwhich includes means for collecting ink which tends to roll down from the cylinder and leak into the housing of the duplicating machine.

These and other objects of this invention will appear hereinafter and for purposes of illustration, but not of limitation, specific embodiments are shown in the accompanying drawings in which* FIGURE l is a cross-sectional view of an inking cylinder provided with the improvements of this invention;

FIGURE 2 is a perspective view of an absorbent pad adapted for use in accordance with this invention;

FIGURE 3 is a detail sectional view of ink collecting means which are incorporated with the inking cylinder for achieving the objects of this invention; and

FIGURE 4 is a fragmentary sectional view taken about the line 4 4 of FIGURE l.

The concepts of this invention provide improvements in inking cylinders of the type which include a cylindrically curved, perforated portion for transfer of the ink from the cylinder reservoir to the ink pad. Elongated slots are formed in the cylinder adjacent the ends of the perforated portion for receipt of ink which tends to pass beyond the ends of the perforated portion and roll down into the mechanisms below.

The slots formed in the cylinder surface open into an ink collecting chamber which extends within the cylinder and outlets are provided in the chamber for passage of ink back into the ink reservoir. In a preferred form of the invention means are provided within the chamber for facilitating the passage of ink into the chamber. Such means, which may take the form of an absorbent pad or means having a capillary action with respect to the ink, are provided for contact with the ink pad to insure passage of the ink in the desired manner.

The accompanying drawings and the following related explanation will provide a more specific description of the inventive concepts. FIGURE 1 illustrates in crosssection an inking cylinder having an ink tank or reser- 3,147,697 Patented Sept. 8, 1964 ICC voir 12 and a cylindrically curved portion 14. Perforations 16 are provided in the curved portion for passage of ink to an ink pad 18 which in turn will transmit ink through openings in a stencil 20 to produce copy.

The stencil and ink pad may be secured to the cylinder in any suitable manner. For example, the stud 22 and the guide pin 24 may serve to provide tensioning means of the type described in the United States patent to DuBois No. 2,916,990, issued December l5, 1959.

Slots 26 are formed in the drum surface adjacent the ends of the perforated portion 14. The slots extend transversely of the cylinder and open into ink collecting chambers 28. Openings 30 are provided at the ends of the transversely elongated chamber for transferring ink collected into the cylinder reservoir.

In a preferred form of the invention there are provided within the chambers 28 means 32 for absorbing or otherwise aiding in the collection of ink. The means 32 can be composed of any material capable of collecting the ink from the pad 13 and aiding in transferring the ink back into the ink reservoir. For example, the felt pad shown in FIGURE 2 can comprise the means 32, the felt serving to absorb any ink soaking through the ink pad and tending to drip over the edges of the cylinder. It Will be noted that the edge 34 of the pad is tapered whereby this edge will be flush with the surface of the cylinder. With this design the ink pad will directly contact the means 32 and more eflicient drawing of ink into the chamber will be accomplished. Speciic examples of suitable felt composions include white felt, designated American Felt No. 51,018 and gray-black felt, designated Rhopac No. 30,103.

Various other means can be employed for aiding in drawing ink into the chamber 28. These means can be porous compositions adapted to absorb the ink or they may include various laminated constructions having passages between the laminations for drawing in the ink by capillary action. Thus, corrugated materials can be laminated to provide suitable passages or a plurality of closely spaced straw-like members with capillary passages could be employed.

Additional more specific examples of suitable ink collecting means include laminated olf-set clean-up materials and laminated blotter material, such constructions providing an absorbing as Well as a capillary action in use. Various open cell foam materials having interconnected pores include 5 pound charcoal polyurethane foam, 45 pore polyurethane foam and l0 pore polyurethane foam.

The ink collecting means disposed in the chamber 2S can also be formed from a laminated plastic labyrinth employing various plastic compositions. E flute corrugated cardboard constructions are also useful for this purpose since the construction will provide a plurality of small passages through the chamber 28 whereby the ink will pass into the chamber by means of capillary action. A similar result is obtained when a plurality of vertically aligned straws, preferably relatively small straws with small passages, are used to make up the ink collecting construction. In any event, constructions which are formed from the various materials set forth or from equivalent materials should be designed so that the exposed end of the construction will be flush with the periphery of the cylinder whereby contact with the pad 18 is achieved.

The inking cylinders which are modified in accordance with this invention has been operated over long periods without significant roll-down or leakage. Cylinders of the improved type described have been tested under the most adverse conditions of humidity without experiencing the objectionable leakage. Ink pads, when provided on cylinders of the improved type, readily give up the ink which saturates them after a printing operation to the collecting means of this invention, and the ink is thus passed into the cylinder reservoir without dripping onto other parts of the printing mechanism. y

It will be understood that various modifications may be made in the above described inking cylinders which provide the characteristics of this invention without departing from the spirit thereof, particularly as dened in the following claims.

I claim:

l. In an inking cylinder for a rnimeograph machine in which the inking cylinder includes a rigid cylindrical curved perforated portion and an ink pad extending continuously over said curved portion and secured at the ends thereof to the inking cylinder, the improvement comprising an attachment secured to the underside of the inking cylinder adjacent the ends of said curved portion to define an enclosed collecting chamber therebetween, elongate slots extending through the end portions of the curved portion into communication with said chambers for passage of ink through said cylinder into said charnbers, openings in said attachment communicating the chamber with the ink well within said inking cylinder for passage of ink from the chamber into the ink well, and an absorbent member lling the chamber for drawing ink from the cylinder into the chamber through said slots, said rigid cylindrical curved portion of the cylinder extending beyond the chambers to provide a continuous rigid support for the portions of the ink pad overlying the chambers.

2. An inking cylinder according to claim l wherein said collecting means comprise felt pads.

3. An inking cylinder according to claim l wherein said collecting means comprise laminated pads.

4. An inking cylinder according to claim l wherein said collecting means comprise an open cell foam material.

References Cited in the le of this patent UNITED STATES PATENTS 2,612,834 Sherman Oct. 7, 1952 FOREIGN PATENTS 402,240 Great Britain Nov. 30, 1933

Claims (1)

1. IN AN INKING CYLINDER FOR A MIMEOGRAPH MACHINE IN WHICH THE INKING CYLINDER INCLUDES A RIGID CYLINDRICAL CURVED PERFORATED PORTION AND AN INK PAD EXTENDING CONTINOUSLY OVER SAID CURVED PORTION AND SECURED AT THE ENDS THEREOF TO THE INKING CYLINDER, THE IMPROVEMENT COMPRISING AN ATTACHMENT SECURED TO THE UNDERSIDE OF THE INKING CYLINDER ADJACENT THE ENDS OF SAID CURVED PORTION TO DEFINE AN ENCLOSED COLLECTING CHAMBER THEREBETWEEN, ELONGATE SLOTS EXTENDING THROUGH THE END PORTIONS OF THE CURVED PORTION INTO COMMUNICATION WITH SAID CHAMBERS FOR PASSAGE OF INK THROUGH SAID CYLINDER INTO SAID CHAMBERS, OPENINGS IN SAID ATTACHMENT COMMUNICATING THE CHAMBER WITH THE INK WELL WITHIN SAID INKING CYLINDER FOR PASSAGE OF INK FROM THE CHAMBER INTO THE INK WELL, AND AN ABSORBENT MEMBER FILLING THE CHAMBER FOR DRAWING INK FROM THE CYLINDER INTO THE CHAMBER THROUGH SAID

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