Printing machines feed mechanism

Abstract

The feed mechanism for a printing machine in which printing ink is fed into the recessed design of an intaglio printing plate includes a cylinder open at its upper end and communicating at its bottom with the recessed designs. A piston is housed in the cylinder, the lower end of which piston forms a chamber at the bottom of the cylinder. The piston rod extends above the cylinder and carries a support member at its upper end, the support member carrying a head. A second cylinder rests upon the top of the first cylinder and receives the head which is slidable therein within limits. A spring is interposed between the head and the bottom of the second cylinder. The piston and piston rod have a bore forming a second chamber provided at its upper end with an ink supply inlet. A hollow relief piston is slidable in the lower end of the bore communicating with the second chamber and communicating through inlet openings with the first chamber. A ball valve in the lower end of the relief piston is normally spring-biased to close the outlet passage of the relief piston, and a second spring in the bore above the relief piston normally urges the relief piston into position in which the ball valve closes communication between the first chamber and the opening in the bottom of the first cylinder. The piston rod is adapted to receive printing pressure whereby the chambers will be contracted by the application of pressure on the printing plate during printing, and will expand when such pressure is released, the chamber expansion causing a further supply of ink to be sucked into the chambers ready for the next printing operation; and the ball valve being closed automatically by application of said pressure.

I claim: 
     
       1. A feed mechanism for the type of printing machine in which printing ink is fed into the recessed design of an intaglio printing plate through the thickness of said plate, comprising a cylinder open at its upper end and having its bottom adapted to communicate with said recessed design; a piston in said cylinder forming with the bottom of the cylinder an ink chamber; a piston rod for the piston extending above the cylinder; a head carried by the upper end of the piston rod; a second cylinder disposed upon the first cylinder and slidably receiving said head; a spring interposed between said head and the bottom of said second cylinder; said piston and piston rod having a bore therein forming a second ink chamber adapted to communicate with an ink supply; a hollow relief piston slidable in the lower end of said bore communicating at its top with the second chamber and also communicating through lateral openings with the first chamber when the relief piston is projected to expose said openings below the first piston; a ball valve in the lower end of the relief piston and cooperating with a valve seat and normally spring-biased to close the lower end of the relief piston; and a second spring in said bore above the relief piston normally urging the relief piston into position in which the ball valve closes communication between the first chamber and the opening in the bottom of the first cylinder; said piston rod being adapted to receive printing pressure, whereby said chambers will be contracted by the application of pressure on the printing plate during printing, and will expand when such pressure is released, thereby causing a further supply of ink to be sucked into the chambers ready for the next printing operation. .Iadd. 2. A feed mechanism for the type of machine in which fluid is fed into the recessed design of an intaglio plate through the thickness of said plate so that the fluid is deposited on the material in the form of the design, comprising a housing part having an outlet opening for communication with said recessed design, a first piston movable in said housing part and forming therewith a first chamber, means for delivering fluid into said first chamber, said first chamber being contracted during movement of said first piston in one direction thereby increasing the fluid pressure in said first chamber, and an outlet valve means carried by said first piston and movable relative thereto by said fluid pressure in a direction opposite the direction of movement of said first piston in contracting said first chamber to effect opening of said outlet opening, said outlet valve means having surface portions against which said fluid pressure acts to effect said movement in said opposite direction, said first piston having a bore therein forming a second chamber adapted to communicate with a fluid supply, and said means for delivering fluid into said first chamber includes means defining at least one opening communicating said chambers, and further including means for restricting fluid flow through said one opening upon movement of said first piston relative to said housing part, and a second piston in said bore and carrying said outlet valve, and said second piston having said surface portion against which the increase in the fluid pressure in said first chamber acts causing movement of said second piston into said bore to effect opening of said outlet opening. .Iaddend..Iadd. 3. A feed mechanism as defined in claim 2 wherein said second piston comprises a hollow member connected with said fluid supply, and said outlet valve means comprises a relief valve member movable relative to said second piston to communicate said recessed design with said second chamber when the pressure of the fluid acting on said valve member exceeds a predetermined pressure to thereby provide for pressure relief. .Iaddend. .Iadd. 4. A feed mechanism as defined in claim 2 wherein said second piston is hollow, and said means defining at least one opening communicating said chambers comprising a portion of said second piston, and said means for restricting fluid flow through said one opening comprises a portion of said first piston which slides relative to said opening. .Iaddend. .Iadd. 5. A mechanism for use in applying a fluid design onto material comprising a plate having a recessed design therein in accordance with the fluid design to be applied to the material and a passage through the thickness of the plate communicating with said recessed design, a fluid injector unit for delivering a charge of fluid under pressure through said passage to said recessed design when the plate and material are in sealing pressure relationship, said injector unit including a main piston movable in a first chamber to force fluid from said first chamber into said recessed design and means for relieving said pressure of the fluid in said recessed design, said means for relieving the pressure of the fluid in said recessed design comprising a member supported by said piston for yielding movement and having a surface portion exposed to the pressure and which yields in response to a predetermined pressure of the fluid acting thereon to thereby effect said pressure relief, said main piston having a passage therein through which fluid flows, an auxiliary piston located in said passage, said auxiliary piston having a second chamber communicating with said passage in said main piston and through which fluid flows, means communicating said second chamber and said first chamber to provide for fluid flow therebetween, and said member being carried by said auxiliary piston. .Iaddend..Iadd. 6. A mechanism as defined in claim 5 wherein said member comprises a valve means movable in response to said fluid pressure and which opens to communicate said recessed design with said first chamber. .Iaddend..Iadd. 7. A mechanism as defined in claim 5 wherein said injector unit comprises a housing part having an outlet opening, and said member comprises an outlet valve means for blocking flow of fluid through said outlet opening and movable relative to said main piston to effect opening thereof. .Iaddend.