US3491683A - Printing member with self-contained ink supply means - Google Patents

Description

Jan. 27, 1970 H. F. FARROW 3,491,583

PRINTING MEMBER WITH SELF-CONTAINED INK SUPPLY MEANS Filed Jan. 19, 1967 i z- Inn -HW@@ W B I United States Patent 6 Int. Cl: B411? 31/00 U.S. Cl. 101-125 2 Claims ABSTRACT OF THE DISCLOSURE Printing apparatus comprising a main frame open at top and bottom; a printing plate closing the bottom of said frame and having on its outer face an engraving and having on its inner face grooves which communicate with the engraving; a plunger plate closing the top of said frame and which is displaceable towards and away from the printing plate; an ink reservoir closed on one side by the printing plate and on the other side by said plunger plate, said reservoir being sealed all around by a resilient sealing member which is mechanically compressed between the printing plate and plunger plate and which is sufficiently compressible to permit the plunger plate to force ink through the grooves and into the engraving; and an absorbent pad arranged to hold the ink in suspense by absorbing ink with a sponge-like action when the mechanical pressure applied to the plunger plate is relaxed at the conclusion of the printing operation.

This invention relates to printing processes and apparatus, and comprises improvements in the method of feeding ink to the printing surfaces of engraved printing plates or dies by forcing the ink through passages extending through the thickness of the plate and communicating with the engraving so that ink can be forced through the printing plate and into the engraving by hydraulic pressure.

In the printing process according to the present invention, the engraved surface of the printing plate is brought into contact with the surface to be printed on and then mechanical pressure is applied to the printing plate and hydraulic pressure is applied to the ink so as to force it through the ink passages and into the engraving. Thereafter, the mechanical pressure applied to the printing plate is relaxed and a partial vacuum is produced in the ink passages sufficient to hold the ink in suspense when the printing plate is retracted after completing a printing operation.

The invention includes an improved ink feeding apparatus comprising an ink reservoir or container closed on one side by the printing plate and on the other side by a piston or plunger, and sealed all round by a rubber or like resilient sealing member which is mechanically compressed between the printing plate and the piston or plunger and is sufficiently compressible to permit the piston or plunger to force ink through the ink passages and into the engraving. The invention also includes a device for charging the reservoir or chamber with printing ink which consists of a sachet, i.e. a thin-walled sealed container which can be inserted into the reservoir or chamber above referred to and subsequently burst by the application of pressure to the piston or plunger so as to deliver its contents into the reservoir or chamber.

The invention and its subsidiary features will be fully understood from the following more detailed description by way of example of one embodiment thereof, reference being made to the accompanying drawing in which:

FIGURE 1 is a perspective view of a printing appliance according to the invention designed for use with a hand press.

FIGURE 2 is a section taken on the line 2-2 of FIGURE 1.

FIGURE 3 is an exploded view of the appliance shown in FIGURES l and 2 showing its component parts separated from one another.

As shown in the drawing, the appliance comprises a main frame which forms the sides of a shallow box having a bottom wall formed by a printing plate 2. The printing plate may be laminated sheet of plastic material which fits into undercut grooves 3 (FIGURE 3) in the sides of the frame 1 so that it can be slid into position and can easily be detached from the frame when required. The printing plate has on its front face an engraving 4 (FIGURE 1) capable of being transferred to paper or other material by an intaglio printing process. On its rear face it has a'number of grooves 5 (FIGURE 3) which communicates with the engraving in the front face through holes cut or drilled through the material of the plate.

The main frame 1 surrounds a space which is closed on one side by the printing plate 2 and on the other side by a piston or plunger in the form of a plate 6 which fits within the frame so as to be displaceable towards or away from the printing plate. The plate 6 is attached to the frame 1 by keys 7 which consist of screws threaded through tapped holes provided for them in the frame 1 and projecting into the grooves 8 in the piston or plunger, the grooves being such as to permit the piston or plunger to move towards and away from the printing plate. On its side facing away from the printing plate, the piston or plunger 6 is attached to a pressure plate 9 adapted to be engaged by the movable plate or a hand press.

In the space between the printing plate 2 and the piston or plunger 6 there is inserted a renewable pack consisting of a number of sheets of permeable material such as nylon fabric 10 disposed close to the printing plate, a number of thicknesses of absorbent material such as felt overlying the fabric and a sealed sachet 12 containing a charge of ink overlying the felt. The sealed sachet 12 is made of metal foil or other thin sheet material designed to burst when compressed between the piston or plunger 6 and the felt 11. A thin frame 13 having shallow teeth or projections 14 is inserted between the sachet and the felt to facilitate the operation of bursting the sachet. The wall of the sachet 12 which faces the felt 11 may be made thinner than the opposite wall to ensure that the wall facing the felt will be fractured.

The pack consisting of the fabric sheets 10, felt sheets 11, frame 13 and sachet 12 as described above is enclosed all around its edges in a frame 15 made of rubber or other compressible material capable of forming a seal. This compressible frame fits within the main frame 1 and is compressed between the printing plate 2 and the piston or plunger 6. It seals the space between the printing plate 2 and the piston or plunger 6 all around the pack, and thus cooperates with the printing plate and piston or plunger to form a compressible reservoir or chamber for containing the ink.

In use the appliance is placed in a press capable of exerting downward pressure on the piston or plunger 9, the paper sheet or other material to be printed upon being inserted between the printing plate and the supporting plate of the press.

As the piston or plunger is pressed downwards by the action of the press, the rubber or other compressible frame 15 is compressed. In consequence, the teeth 14, on the member 13 penetrate the sachet 12 allowing ink to escape into the reservoir and penetrate the felt 11 and fabric sheets 10. As the press is tightened the felt and fabric sheets are pressed into the grooves 5 in the back of the printing plate and ink is thus forced through the ink passages in the printing plate and fill-s the engraving.

Relaxation of the press allows the rubber or like compressible' frame 15 to expand, thus creating a partial vacuum sufiicient to'hold the ink in suspense. This is assisted by the natural resilience of the felt 11 and fabric sheets which causes them to tend to return to their natural state and thus to exert suction in the grooves 5 by absorbing ink with a sponge-like action. A fresh paper or othersheet to:be printed upon can now be inserted and the next operation of ,the press. again forces ink .through the ink passages and into the engraving. The piston or plunger 6 aided by theisponge-like action of the absorbent material 11 thus has a pumping action which delivers fresh ink to the engraving for each successive printing operation. a g

The rubber or like compressible frame 15 serves both as a seal for preventing the escape of ink from the reservoir and also as a thrust member for transmitting mechanical pressure to the printing plate. It also serves' to retract the piston or plunger when the press head is retracted so as to form a partial vacuum sufficient to hold back the ink ready for the next printing operation.

The ink used in this invention may be a printing ink such as is used for die stamping or any substance or composition which can be used as a substitute' for ordinary printing ink. e I

I claim: 1. Printing apparatus comprising a main frame open at top and bottom and having vertical side Walls defining a chamber; a printing plate closing thebottom of said frame and having on its outer face an engraving and having on its inner face grooves which communicate with the engraving; a plunger plate closing the top of said frame and received within the side walls and displaceable towards and away from the printing plate; an ink reservoir within the chamber between the printing plate and plunger plate, said reservoir being adapted to hold a sealed container containing an ink supply, and a frame member. having container bursting means thereon, said ink reservoir being confined within; the chamber and being sealed Aherein by a resilient compressible sealing member extending around the reservoir and positioned beneath the plunger plate, said plunger plate when pressed downwardly within said main frame compressing the ink reservoir container onto the frame;;member,,means to burst same to cause: ink to fiow into the printing plate grooves and onto the engraving; and an absorbent pad arranged within the chamber above the printing plate adapted to absorb the flowing ink to hold same in suspension with a sponge-like action when the printing pressure is released.

2. Apparatus as claimed in claim 1, wherein said absorbent pad consists of a number of sheets of permeable material disposed close to the printing plate and a number of thicknesses of compressible absorbent material overlying the fabric.

References Cited L UNITED STATES PATENTS" 1,170,932 2/1916 Pr itchard 101-125X 1,647,207 11/.1927 Wright "101 1,782,877 11/1930 Madden 101- 125 3,055,296 9/1962 Farrow 1o1 1s1 3,s2e,1so 6/1967 Lofgren 1o1 V-333x 3,342,911 9/1967 Funahasrr'i 101.-327X WILLIAM B. 'IVENN, Primary Examiner;

7 U.S. c1. X.R. 101+333; 118-464

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