Abstract: A screen printing assembly attachable to a silk screen frame including a support frame positionable adjacent and attachable to the screen frame. A squeegee and flood bar assembly deposits and forces ink on and through the screen and onto a substrate disposed adajcent the screen. The assembly includes a mechanism movable along the support frame and the screen frame and a flexible sheet is attached to and moves with the mechanism. The flexible sheet is sealed to the support frame, and forms in part a sealed chamber in which the squeegee and flood bar assembly deposits the ink on the screen. Solvents can be sprayed into the sealed chamber which contains the solvent so that it does not escape not the atmosphere. An inert gas is injected into the chamber displacing the oxygen in it so that the ink does not dry out as rapidly, and safely maintaining the contained solvent. A method for screen printing using this sealed chamber.

Abstract: The printing unit (1) operating with an electrostatic printing aid has an inductor device (7) for transmitting an electrostatic charge to an outer-shell layer (5) of a back-up cylinder (4). The inductor device is provided on one end face (14) of the back-up cylinder and engages over this end face in the manner of a lid. A continuous annular air gap (15) is located between the end face and the inductor device. Inductor electrodes (9) serve for transmitting the electrostatic charge to the outer-shell layer in a contactless manner and are arranged, concealed against outside access, on the inner face of the inductor device and are aligned by means of their electrode tips with an end-face edge (10) of the outer-shell layer (5). So that no impurities can penetrate into the air gap, it is sealed off or constantly scavenged by compressed air.

Abstract: A steel ink metering roller for use in lithographic printing having an engraved surface that has been nitride hardened followed by an oxidizing process that results in a surface with a composition of mainly Fe.sub.3 O.sub.4.

Abstract: A system designed to enable persons incapable of manipulating a writing implement to sign papers and/or documents comprising a holder for the document to be signed, a holder for a transfer sheet for holding the transfer sheet adjacent that portion of the document to be signed and an implement defining the signature to be applied to the document for pressing the transfer sheet into transferring engagement with the document.

Abstract: A method and apparatus for supplying a liquid medium, such as viscous printing ink, to the distributor and transfer rollers of printing machines. The apparatus includes an arcuate shaped distributor plate, an ink feed for dispensing a controlled quantity of liquid medium onto the distributor plate, and a feed roller that is mounted for cyclic movement in a path whereby it is rolled on the distributor plate to mix and uniformly spread the medium along the plate and about the periphery of the feed roller and then is moved into contact with the machine distributor roller to transfer the liquid medium thereto in a controlled manner. In one embodiment, the feed roller is moved in a cyclic circular path so that it first engages the distributor plate and then the distributor roller, and in another embodiment is moved in a reciprocating manner back and forth on the distributor plate and then engages the distributor roller.

Abstract: A printing hammer assembly for use in impact printers includes a printing hammer which has an impact surface and an armature and which is supported to be movable in a reciprocating manner along its longitudinal axis, a driving solenoid which drives to move the printing hammer forward when energized against the force of a coil spring which normally applies a biasing force to the printing hammer in the backward direction and a yoke leading a magnetic flux produced by said solenoid to the armature of printing hammer. A pair of magnets are disposed such that they are magnetically repulsive to each other with one of them fixed in position and the other movable over a predetermined distance thereby allowing to absorb the rebounding energy of the hammer when it returns to its home position.

Abstract: A rotary printing machine has a plate cylinder and a liquid supply apparatus comprising an inker and a damper. The liquid supply apparatus includes rollers and an endless band guided over two deflection rollers. The band, which has a surface that accepts ink and damping fluid and extends over the width of the rollers, is provided with guide elements cooperating with counterpart guide elements attached to the machine. The guide elements and counterpart guide elements are embodied such that the band is displaceable at right angles to the axes of two rollers and is additionally pivotable at least about one of the axes of a deflection roller. Positioning means supported firmly on the machine are also provided for fixing the band in at least two different operating positions, in which the band is in contact with one or two rollers of the liquid supply apparatus.

Abstract: An ink metering arrangement for a printing press including a fountain roller having a plurality of slides arranged edge-to-edge in respective column positions, each slide being adjustable so that its tip forms a gap with the roller thereby determining the rate of ink flow in the corresponding column position. Each slide has a reversible motor for driving the slide over a limited range of movement with respect to a slide reference position. A potentiometer is connected to the motor for producing an electrical output signal corresponding to the degree of slide displacement, the potentiometer having a stop to establish a reference output condition. A slip clutch is interposed in at least one of the motor connections so that when the motor is energized in a first direction the potentiometer and slide are both driven to their reference positions accompanied by relative slipping movement of the clutch notwithstanding the fact that the tip of the slide may have been shortened by wear against the roller.

Abstract: A gripper device for transporting and registering sheets of any type under the printing heads of silk screening and the like printing machines, which comprises a box-like supporting body having hingedly connected thereto, against the bias of preloaded spring members, a plate-like element forming a flat jaw, and juxtaposed thereto, a plurality of flat surface gripper elements which are set in mutual alignment and for oscillation about a parallel axis to said juxtaposed jaw and adapted to be brought close against said juxtaposed jaw by means of at least one slide element which is driven reciprocatingly by a drive shaft from the silk screen printer, said slide element being provided with an actuating means cooperating with means associated with said flat jaw and with said plurality of juxtaposed gripper elements and adapted to produce, as said slide is being reciprocated, a rotation of said plurality of gripper elements about their own axes toward said opposed flat jaw and to allow said flat jaw to be disengaged

Abstract: An apparatus for printing a pattern of a flat horizontal screen on an underlying substrate comprises a wiper assembly mounted on a carriage above the screen and an electromagnet beneath the screen reciprocable along the latter jointly with the carriage. A cradle limitedly pivotable on the carriage about a horizontal axis extends across the screen and supports, via adjustable holders, a working wiper and a distributing wiper on opposite sides of its pivotal axis. The working wiper, which may be a blade or a roller, directly overlies the electromagnet and is magnetizable and/or accompanied by a magnetizable mass whereby energization of the electromagnet attracts the side of the cradle bearing that wiper to press it against the screen for forcing dyestuff therethrough onto the substrate, this side trailing during a printing stroke.

Abstract: A device for adjusting the position of the printing head of a printer has a leaf spring received in a groove formed in the carrier of the printer. The spring is bent into a doglegged form such that the spring force is applied to both ends of the carrier backwardly. The printing head is mounted on a support plate which is provided with a groove with which the anchoring portions of the leaf spring engage. The support plate is mounted on the upper surface of the carrier so as to be slidable forwards and backwards by a counter-sunk screw.

Abstract: To prevent introduction of paper scraps or torn paper into the inker of a web printing machine, a web paper tear sensor (17, 18) controls a hydraulic or pneumatic cylinder-piston unit (25) which severs engagement between an ink supply roller (13) and an ink application roller (12) while maintaining contact of the ink application roller with the plate cylinder (4) of the printing machine; the greater quantity of ink on the ink application roller will cause paper to adhere to the ink application roller, and thus wrap itself about that roller, severance of contact with the ink supply roller (13) preventing introduction of torn paper into the inker.

Abstract: Method and apparatus for printing a design with a stencil screen including a resilient membrane formed by reversely-bent portions in the screen between a desired pattern defined by a paint-pervious opening in the screen and edge portions of the screen. The reversely-bent portions of the screen are filled with an elastomeric material and extend beyond the bent portions of the screen. A coating of an elastomeric material may be applied to the outside areas of the reversely-bent portions of the screen and adhered to the elastomeric material in the pocket of the screen by permeating the screen openings.

Abstract: An arrangement for longitudinally oscillating a doctor blade relative to the form cylinder in a printing press. The arrangement includes a double armed rocker having one arm coupled to the doctor blade and the other arm coupled to a hydraulic cylinder. The rocker is mounted on a central eccentric portion of a pivot shaft through a one way idler bearing and the pivot shaft is rotatably supported in a counteracting one way idler bearing. By oscillating the rocker, through sequential operation of the double acting cylinder, the pivot axis of the rocker is continuously displaced, causing the points of reversal of doctor blade movement to be continuously varied independently of the press operation, while maintaining a uniform stroke. In the illustrated embodiment, a pneumatic control is provided for controlling operation of the hydraulic cylinder, and thus the rocker arm and doctor blade movement.

Abstract: A pullout roller assembly for a printing press comprising an upper roller and a mounting therefor, the mounting including a bellcrank lever having an upright leg and a horizontal leg joined to the upright leg by an elbow. The roller is mounted on a fixed axis of rotation to the elbow and the outer end of the horizontal leg has a ball type universal connection to the frame of the press. The upper end of the upright leg has a pocket formed therein in which a spherical output end of a prime mover is positioned for exerting a force against a flat surface in the pocket without binding for biasing the lever and thus the pullout roller mounted thereon against the periphery of a companion roller, which is normally powered, for grasping a sheet or web of paper passing between the rollers and moving the paper through various stations of the press.

Abstract: A strip assembly for a printing device having an endless type band frictionally driven by drive and idler pulleys between print hammers and a platen comprises a wear strip and wiper strip attached together at a common end. The wiper strip has a wiper portion extending from the point of attachment which terminates in a scraper edge. A retention device mounted in proximity with the drive pulley comprises means connectable to the common end to hold said wear strip under tension and said wiper strip in spring loaded condition with the scraper edge in contact with the drive surface of the drive pulley for cleaning wear strip residue and other deposits from the pulleys and the type band.

Abstract: A system for automatically removing dust from a plate cylinder of a printing press has a laminated structure for inputting a dust removal position, which comprises (a) a printed circuit substrate bearing thereon a reference signal input circuit of comb form with numerous comb conductors and position signal read-out circuits alternatively interposed respectively between adjacent pairs of comb conductors and (b) a pressure-activated conductor sheet superposed in laminated state on and over the circuit substrate. When a printed material having a printing defect due to dust on the printing plate is laid over with correct register on this laminated structure, and the part of the defect is pressed, the nearest conductors of the input circuit and of the read-out circuit are shorted to designate the position of the defect. The resulting signal is processed and is sent to a dust removing mechanism to move a disk-shaped elastic dust removing head to the corresponding dust existing part of the printing plate.

Abstract: A device of securing a film bearing indicia on the surface of the printing roll under tension in an efficient and automatic way, the device comprising: a first engager and a second engager provided at each end of the film, a first receiving means and a second receiving means provided adjacent to each other on the peripheral surface of the printing roller, wherein the first receiving means is adapted to receive the first engager of the film and wherein the second receiving means is adapted to receive the second engager of the film, the second receiving means comprising a slotted rod rotatively placed in an accommodation groove produced in the printing roll, and a pinion secured to the terminating end of the rod, a rotor rotatively provided at one end face of the printing roll, the rotor having a first tooth zone and a second tooth zone in its periphery, wherein the first tooth zone is adapted to engage with the pinion and wherein the second tooth zone is adapted to engage with a ratchet mechanism provided in p