Abstract: A device for securing flexible printing plates under tension on a plate cylinder of a rotary printing machine having tensioning rails operatively associated with both ends of the plate and being braceable against side walls of a transverse channel formed in the plate cylinder for tensioning the printing plate includes a device for selectively stretching and compressing at least one of the ends of a printing plate in axial direction of the plate cylinder, the tensioning rail operatively associated with the one plate end being of one-piece construction and having a clamping member disposed at a middle region thereof and respective tensioning segments disposed at end regions thereof and actuable for stretching and compressing the one plate end.

Abstract: A quick-action plate clamping mechanism for a plate cylinder of a printing press consists of a pressure strip disposed axially in a recess along the gap in the plate cylinder wherein the recess extends behind the plane of the rear gap wall and parallel thereto, the pressure strip being displaceable in the gap by means of an eccentric bolt which is disposed outside the cylinder center plane parallel to the clamp screws in the rear clamping bar and with specially formed recesses in the pressure strip and corresponding projections on a co-acting member being provided which are respectively situated opposite the clamp screws and supported by compression springs thereby enabling a uniform parallel clamping movement to be carried out in the direction of the rear clamping bar.

Abstract: A clamping device for a printing plate mountable on a plate cylinder of an offset printing machine and having perforations formed at leading and trailing edges thereof, as viewed in direction of sheet travel through the machine, the clamping device includes clamping bars formed with hooks respectively engageable in the perforations formed in the printing plates, the clamping bars being disposed in a channel formed in the plate cylinder, one of the clamping bars being pivotable about a pivot point diagonally to a longitudinal direction of the plate cylinder, the pivot point being located in the cylinder channel substantially on a center line of the cylinder extending transversely to the longitudinal direction thereof, and adjusting means mounted in the cylinder channel for moving another one of the clamping bars in the longitudinal direction of the cylinder, the other clamping bar having additional degrees of freedom of movement accommodating an accompanying diagonal movement which respect to the longitudinal

Abstract: Two intaglio printing plates having a total length equal to the circumference of the cylindrical barrel (1) of a plate cylinder are prepared. The cylindrical barrel (1) is expanded radially, and on the portion of its surface corresponding to the first plate (4) to be attached an epoxy film is deposited. The first plate (4) is applied on the epoxy film in the exact position. On the remaining part of the cylindrical barrel (1) one or a plurality of metal sheets (5) are deposited for ensuring the continuity of the cylinder surface. The plate (4) to be attached is surrounded by a tightening ribbon (6) covering completely the plate (4). Heat is used for softening the epoxy film and the ribbon (16) is tightened by exerting tractive forces beginning from the center of the two ends of the ribbon and advancing towards the peripheral edges. The epoxy film is allowed to set, the ribbon (6) and the sheet or sheets (5) are removed.

Abstract: Magnetic cylinders with an image plate or an offset blanket carrier plate have annular pole pieces and magnets which maximize either the resistance of the plate to peel-off or the attractive force intensity with a nominal displacement of the plate from the cylinder for typical operating conditions. The plates are precurved, preferably with a radius slightly less than the cylinder radius.

Abstract: To reduce the width of the groove (6,7) within which the end portions of rubber blankets (14) of a blanket cylinder are attached, and thus prevent oscillations occurring due to roll-off of the groove against another cylinder, which may likewise have a groove, the rubber blanket is formed to have a reinforcing strip which is shorter than the axial dimension of the rubber blanket, the rubber blanket being formed with converging sides, the slot width of the groove adjacent the circumference of the cylinder being narrow in the end regions to have the width of only about twice the width of the thickness of the rubber blanket. In some constructions, the rubber blanket is a composite blanket formed of a substrate and an ink transferring cover; the end portion of the rubber blanket, which fits within the groove, can be left free of the ink transferring rubber cover so that the width of the slot at the end portion can be narrowed even further to only about twice the width of the substrate.

Abstract: A flexible wrap-on printing plate structure has a flexible printing plate body extending between opposite first and second edges at which the printing plate structure is attached to a rotary printing form cylinder. A thickening of the printing plate body or other means extend along a third edge of the printing plate body between the mentioned first and second edges for mechanically stiffening the printing plate body along that third edge, so that no warping of the printing plate structure and no printout of printing plate margins can occur.

Abstract: The first end of the printing plate is introduced between the jaws of a clamping device housed in an axial groove of plate cylinder and tightened by means of screws. The plate is stretched on the cylinder surface and its distal end is engaged between the jaws of a second clamping device located in the axial groove, and the jaws are tightened by means of screws. The plate is stretched by feeding hydraulic jacks set at spaced intervals along the lower jaw of the clamping device of which the pistons react against the adjacent radial face of the groove, thus moving the clamping device in the peripheral direction of the cylinder. After obtaining the desired adjustment the displaced clamping device is locked by tightening in a tightening body responsive to screws projections of the displaced clamping device in order to lock same, and the pressure in the hydraulic circuit is relieved.

Abstract: The invention relates to a device for fixing a plate on a cylinder, while permitting to quickly control, at certain instants, the application and fixation of this plate on a particular angular portion of this cylinder and, at other instants, the disengagement of this plate.It is characterized by the fact that, in addition to means (9) enabling the plate (3) to be brought against the cylinder or, on the contrary, separating it from its area of support, it comprises means (10) for fully applying on the cylinder both the median portion and the ends of the plate.Application to the mechanical construction industry and, more particularly, to rotary printing and cutting machines.

Abstract: In the case of a device for holding offset or other plates on the plate cylinder of a printing press with two clamping members on the two sides of a well running in the axial direction of the cylinder and each having a gripping part of clamping the hooked ends of the plate and at least one of the members may be rocked about an axis parallel to the axis of turning of the cylinder, the necessary width of the well may be greatly decreased in the clamped condition of the system of one of the clamping members, that is able to be rocked, takes the form of a segment bar having a cross-section that is generally three-sided and segment-like. This bar may be placed next to an outer face of the cylinder body and has an outer face lined up with and continuing the outer face of the cylinder body.

Abstract: The gap (15) formed between the end portions (5) of a gravure printing plate (3) which is anchored in a groove (2) of a printing cylinder (1) on which the plate is mounted is covered with a sheet (6) which overlaps the end portions. The gap cavity (9) thus formed is then filled with a thermoplastic and/or hardenable material and when this has hardened the cover is removed.

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

Abstract: There is disclosed, printing apparatus including a drum having oppositely facing semicylindrical saddles mounted thereon with elongated spaces between the edges of the saddles. The longitudinal edges of the saddles are beveled radially inwardly on themselves and an elongated laminated alternate pole magnet array is mounted in the space between the saddles. A flexible printing plate is provided along one edge thereof with an inwardly bent angle for engaging the beveled edge of the saddle and the opposite edge of the plate is provided with a lockup pad for magnetically engaging the elongated magnet in the space.

Abstract: A printing blanket holding bar adapted for insertion into a channel longitudinally extending along the periphery of a reel, the channel having a pair of flat, generally parallel side walls extending from the periphery of the reel, said holding bar comprising a base having a first flat surface and a second flat surface generally parallel therewith, each base surface adapted to be disposed against and cooperate with a corresponding channel side wall when said holding bar is operably inserted into the reel channel, a blanket clamping arm carried by said base and adapted to cooperate with said base to clamp an associated printing blanket end therebetween, a top surface of said clamping arm adapted to support the printing blanket when said holding bar is operably inserted into the reel channel and when the printing blanket is wrapped at least approximately one revolution around the reel, at least a substantial portion of said arm top surface being bowed, the tip of said arm tapering to substantially zero thickness

Abstract: In a cylinder with replaceable shaped plates for applying a predetermined pattern of adhesive to webs of material, the cylindrical surface has at least two axially spaced recesses each containing a rocker arm pivoted about an axial shaft, one end of the arm carrying a gripper engaging over one margin of a pattern plate and its other end carrying a quick-release screw clamp for the opposite pattern plate margin.

Abstract: A paste sector for applying paste in a predetermined pattern to an item being manufactured, such as to the open bottom portion of a partially formed bag in a bag making machine. The paste sector is molded from a substantially resilient non-metallic material, and includes an added-thickness bottom portion adapted to be directly fitted to a paste sector shaft. The paste sector is preferably injection molded from a rubber-like urethane material, and is provided with a Teflon coating having an affinity for the low viscosity paste employed in the fabrication of paper bags.

Abstract: A split-shell magnetic printing cylinder is made from first and second half cylinders which are joined along a plane through the axis of the cylinder. Each half cylinder or "split-shell" has first and second similar end plates with laminations stacked between the end plates. The laminations alternately form pole pieces and spacers which hold permanent magnets in contact with adjacent pole pieces. A plurality of core bars extend between and are secured to the end plates, and they are located to engage an inner curved edge of the laminations when the laminations are assembled to the core. The core bars are welded to the inner edges of the laminations for holding the laminations firmly in place. The rods extending through the laminations may also be secured to the end plates to hold the laminations. The inner edges of the laminations, the core bars and the welds are all embedded in a layer of resin such as epoxy. The split cylinders are secured together with shoulder bolts securing the end plates together.

Abstract: A method of making a plate cylinder for a web printing press in which a hollow cylinder with a conical interior is formed of ductile steel. Two nickel printing plates are formed to shape so that they will fit virtually exactly around the cylinder without joins between them being readily apparent. A cylindrical mould having two semi-cylindrical mould halves is formed with its inner diameter equal to the outer diameter of the plate cylinder being produced. One mould half is placed with its semi-cylindrical inner surface facing upwards and a printing plate is placed inside. Then the hollow cylinder coated with epoxy resin is placed on this plate, and the other printing plate is placed on the cylinder. The second mould half is secured to the first half, and a conical core is forced into the cylinder to expand it radially so that the plates are held under pressure against the mould surface. Then the mould is heated and the resin allowed to set under conditions of temperature and pressure.

Abstract: A device is provided for the rapid clamping of flexible printing plates on the printing cylinder of rotary printing presses which includes a support bar mounted within and adjacent to the front side of a cylinder groove to which the forward end of plate is clamped by means of clamping springs and a clamping arm disposed opposite of the support bar, which is pivotably mounted within and adjacent to the rear side of the groove and has a plate attachment arm to which the rear end of the plate is clamped. The clamping arm is actuated by means of pressure springs in the clamping direction and in the counter direction by adjustment means so that the plate ends may be clamped independently from one another as well as independently of the plate thickness so as to prevent damage to the plates during the clamping operation and an easy servicing.

Abstract: Clamping apparatus is provided for holding thin flexible printing plates in position on a press cylinder. In some embodiments, shim members are attached to the outer periphery of the press cylinder for accurately radially positioning the printing plates with respect to the surface of the press cylinder. A clamping assembly is provided separately from and at a spacing from the shim members for releasably clamping one edge of the printing plate while the other edge of the printing plate is engaged over one of the edge portions of the shim member. The shim members and the clamping assembly are independently and separately attachable to the press cylinder so that the shim members can remain in position while printing plates are exchanged, as well as during removal and/or adjustment of the clamping assembly. A pair of symmetrically arranged lock bars are hingedly mounted for selective engagement with detent portions of the printing plates to accommodate reversal of the clamping direction.

Abstract: There is disclosed, a printing saddle lockup including a saddle mounted on a rotary printing cylinder and having a floating biasing bar disposed at one edge thereof. A recess is formed in the cylinder beneath the biasing bar and a cavity is formed in such bar over the recess and receives a rotary cam having an eccentric peg projecting downwardly therefrom to engage a hair pin shaped spring projecting longitudinally into such recess, such that rotation of the cam in one direction contacts such peg with one leg of such spring such that continued rotation urges the biasing bar in one circumferential direction on the cylinder and rotation of such cam in the opposite direction contacts such peg with the opposite leg of such spring whereby further rotation of such cam urges such biasing bar in the opposite circumferential direction.

Abstract: A printing roller is disclosed comprising a mandrel fitted with a removable cylinder. The cylinder is retained on the mandrel by radially expansible, resilient rings which extend around the mandral. In one embodiment, the mandrel includes a number of cylindrical sections between which the rings are disposed and means are provided for compressing the sections to cause radial expansion of the rings. In other embodiments, the roller mandrel has an internal air passageway which communicates with the grooves receiving the rings and provision is made for delivery of pressurized air to the air passageway so as to cause the rings to expand.

Abstract: A plurality of circumferentially extending mounting recesses are formed in a cylinder assembly and arcuate saddle members having marking means, such as print type, on their outside surface are mounted in the recesses. Each saddle member has a locking recess formed in its inside surface with a pair of spaced apart, flexible locking wires extending therethrough. Mounting studs having a mounting head with a relatively narrow neck portion are affixed to the cylinder within the mounting recesses. The saddle members may be mounted within the mounting recesses by snap-on engagement of the mounting head with the locking wires, and readily removed by snap-off disengagement of the head with the wires. The saddle members may thus be readily replaced and interchanged by means of the snap-on, snap-off mounting and demounting.

Abstract: A fastening bar for securing printing plates to a printing machine, especially a rotary printing press, comprises a base and a clamping bar fastened thereto, the clamping and release of the printing plate being effected by an eccentric shaft. In the base one or more clamping elements are displaceably mounted and have ends juxtaposed with the opposing clamping surface of the clamping bar, the opposite ends bearing against springs which permit compensation for different thickness along the edge of the printing plate.

Abstract: A blanket clamping and tensioning apparatus for use in a blanket cylinder in a rotary printing press is disclosed. An axial groove at the periphery of the blanket cylinder carries a pair of spaced inserts which define an interior chamber. A radially movable clamping bar assembly is carried within the chamber and contacts camming surfaces on the inserts. The ends of the blanket are inserted in the space between the inserts and the clamping bar assembly is moved radially inwardly thereby camming clamping means toward each other to grip the blanket. Four embodiments are disclosed in which there are shown different gripping portions of the clamping bar assemblies.

Abstract: A device for mounting a plastic film based resin plate for use in printing on a plate cylinder has a groove formed along one longitudinal side edge of each of two members having a symmetrical semicircular section and constituting a plate cylinder, each of said two members consisting of a plate cylinder proper and a plate cylinder outer ring, a fixing member made of a resilient material and having a wedge-shaped protrusion adapted to fit into said groove, said fixing member being fixedly secured to a freely rotatable support shaft which is mounted at a position adjacent to groove and is connected through a linkage to a first operating rod.

Abstract: A printing blanket holding bar and printing blanket assembly using same are provided wherein said holding bar comprises a substantially U-shaped member having a bight and a pair of legs extending from opposite ends of the bight and a blanket clamping arm carried by the bight with the arm being adapted to cooperate with the bight to fix an associated end portion of a printing blanket therebetween with the legs being adapted to quickly attach and detach the holding bar relative to a bar support.

Abstract: A flexographic printing roll comprising a rigid base tube having perforations in the form of a plurality of small apertures and a circumferentially stretchable, elastomeric, seamless printing sleeve on said tube strained to grip the tube to retain the sleeve securely on the tube; in which there is provided means on the tube to aid the sliding of the sleeve on the tube. The said means may comprise a circumferential seal which can be pressurized to press on the sleeve and expand it. The said means may comprise an expandable metal segment seal. The said means may comprise a tapering sleeve through which means are provided for applying reducing pressures at points along the surface of the tapering sleeve.

Abstract: An endorser drum assembly for printing data on paper sheets, documents and the like and having an elongated strip preferably formed of resilient material, for mounting about the periphery of a drum. An adjustable clamping means for releasable securement to the drum secures the printing strip thereto.

Abstract: To provide asbestos-cement and like sheets which are formed by build-up of a thin film on a rotating size roll, with an embossed patterned surface; a flexible mould layer of epoxy resin or like mouldable material having counterpart embossments moulded thereon, is removably wrapped about and secured to the size roll with its patterned side outward and before commencement of film build-up on the roll.

Abstract: In a rotary printing machine, the cylinder for holding the printing plate has a printing plate tensioning device formed in it, which includes an adjustably positionable tensioning rail. To adjust this rail, a set of marks is formed on the cylinder. A support base carries an optical device to view the marks. On the base there are tensioning rail engaging adjustably positionable abutments and the alignment of the marks in the field of view of the optical device enables proper positioning of the abutments and of the tensioning rail.

Abstract: A printing cylinder for printing machines comprising a shaft, a sleeve adapted to support a printing block and mounted on the shaft with radial clearance, and an adjusting mechanism provided at each end of the sleeve. Each adjusting mechanism comprises a guide ring and a clamping ring having cooperating conical guide surfaces. A fit between the shaft and the guide ring is so easy that the guide ring may be somewhat tilted relative to a plane at right angles to the longitudinal axis of the shaft, and the clamping ring comprises radial, adjustable securing means and axial adjusting means, whereby it is possible to center the sleeve very precisely relative to the shaft.

Abstract: A master cylinder for an offset or the like printing press includes an arcuate master receiving surface extension section mounted on the cylinder for movement between an inoperative position into the interior of the cylinder and an operative position adjacent the tail end of the stationary master receiving surface of the cylinder. When in the operative position the extension section increases the length of the master sheet receiving surface of the cylinder to accommodate longer than "standard" length master sheets. The extension section is mounted for sliding movement on arcuate guides formed by the movement of a predetermined radius extending from a point off center with respect to the central axis of the cylinder. A locking assembly is included to secure the section in either position. A tail clamp for longer masters is provided on the free end of the extension section.

Abstract: A clamping and tensioning mechanism for mounting a thin flexible printing plate on the surface of a printing cylinder in which a mounting bar is provided having a longitudinal groove formed therein occupied by a clamping bar having upper and lower jaws which are shaped to deform and positively grip the end of the plate. The groove is of dovetail cross section so as to present opposed wedging surfaces having a shallow wedge angle, a spring being interposed in the root of the groove. As a result, when the end of the plate is inserted between the jaws and the mounting bar is subsequently moved in the plate tensioning direction, the jaws of the clamping bar are wedged together to deform the end of the plate and, upon continued movement of the mounting bar, the end of the plate is bodily drawn to tension the plate about the cylinder, thereby to provide positive lock-up.

Abstract: A mechanism for securing mounting blocks for printing plate clamping devices on forme cylinders is disclosed. A mounting block for receiving the printing plate clamping device is located in a paraxial groove formed in the cylinder and is secured therein by means of a pair of longitudinally movable locking bars which are shiftable in longitudinal notches formed on the sides of the mounting block. Means are provided for adjusting the locking bars longitudinally in the locking and releasing directions to selectively secure the mounting block in place or to release it for removal from the groove.

Abstract: A clamping device for securing a thin flexible printing plate with longitudinally extending first and second opposite side edges to the cylinder of a rotary printing press, said clamping device including a semi-cylindrically shaped saddle adapted to be fixedly secured to said rotary press cylinder and to support said flexible printing plate on the saddle's outside face between the first and second longitudinally extending side edges of said saddle, securing means positioned along the first side edge of said saddle for securing the first side edge of the flexible printing plate to said saddle, a rotatable support member journaled to and along the second side edge of said saddle, a plurality of outwardly extending register pins secured to said support member to coact with openings formed along the second side edge of said flexible plate, and a lever secured to said support member for rotating said member to a position such that the register pins extend outwardly away from the second side edge of the saddle to l

Abstract: This invention relates to an improved apparatus and method for locking printing plates to a support, e.g., saddle or cylinder, wherein the support includes a body portion having at least two anchoring means as an integral part thereof, at least one of the anchoring means being incorporated on a spring-mounted bar movable under spring tension to engage and lock printing plates to the support. The invention also relates to apparatus and method for mounting printing plates onto a support comprising an actuating assembly for the spring-mounted bar and which is adapted to move the spring-mounted bar between expanded and compressed positions for the mounting. The spring-mounted bar actuating assembly is mounted beneath the peripheral surface of the support and comprises a pivot arm pivotable at or near its midpoint about a pivot block which is mounted beneath the peripheral surface.

Abstract: Lock-up structure for applying a thin flexible press roll to a generally semi-cylindrical saddle comprising means for fixing one end of a printing plate to one straight edge of the saddle, and a bar at the other straight edge of the saddle. The bar includes means for affixing the opposite edge of the printing plate thereto. Toggle means are provided for swinging the bar into position adjacent the other straight edge of the saddle while applying a predetermined tension to the printing plate.

Abstract: This invention relates to an improved apparatus and method for locking printing plates to a support, e.g., saddle or cylinder, wherein the support includes a body portion having at least two anchoring means as an integral part thereof, at least one of the anchoring means being incorporated on a spring-mounted bar movable under spring tension to engage and lock printing plates to the support. The invention also relates to apparatus and method for mounting printing plates onto a support comprising an actuating assembly for the spring-mounted bar and which is adapted to move the spring-mounted bar between expanded and compressed positions for the mounting. The spring-mounted bar actuating assembly is mounted beneath the peripheral surface of the support and comprises a pivot arm pivotable at or near its midpoint about a pivot block which is mounted beneath the peripheral surface.

Abstract: A shell defining a semicylindrical printing saddle formed on one longitudinal side with a plate mount for receiving one end of a flexible printing plate having printing indicia thereon and on its opposite longitudinal side with a pair of circumferentially outwardly opening bores having sleeves mounted therein and terminating at their inner extremities in respective axially rearwardly facing stop surfaces. A biasing bar projects coextensive with the saddle adjacent such other side and includes a mount for receiving the opposite end of such printing plate. The biasing bar is formed with through bores confronting the respective cavities and has received therein self-contained latch devices including cylindrically shaped hollow latch housings projecting through such sleeves and into the respective cavities.

Abstract: A flexible printing plate carrier comprises a curved carrier plate at least one end of which has mounted thereon a rotatable tubular shaft having an axially extending projection about which a bent over end of the printing plate can be hooked. A pre-loaded torsion spring extends through the tubular shaft to urge the projection towards an edge of the carrier plate and to clamp the printing plate against said edge. Rotation of the shaft to the non-clamping position of the projection is effected by a hand tool insertable into a bearing for one end of the shaft.