Man Roland Druckmaschinen Ag

Maschinenfabrik Augsburg-nurnberg Aktiengesellschaft

Krause-biagosch Gmbh

M.a.n. Maschinenfabrik Augsburg-nurnberg A.g.

M.a.n.-roland Druckmaschinen Aktiengesellschaft Offenbach

Hermann Fischer

Claus D Simeth

Harry M Greiner

Johannes M Schubert

Jan Nemcik

Walter Heidenreich

In the context of a device for the production of printing plates comprising a printing down station with a plate table and an associated illuminating means, which station has associated with it a foil receiving means formed preferably by a foil cassette for unprinted foil and preferably a receiving cassette for printed foil, in the case of which the foil to be printed onto an unexposed or blank printing plate is able to be taken from a foil receiving means by means of a moving vacuum frame, is able to be moved onto the blank plate on the plate table and after exposure is able to be discharged, preferably into a receiving cassette, a high rate of plate production and a smooth manner of operation without damaging the foils may be ensured if the foil conveying device has a plurality of vacuum frames moving in circuits which are out of phase with each other.

Apparatus for the production of printing plates

In the context of a device for producing printing plates comprising a printing down station with a plate table and an associated illuminating means, which station has associated with it a foil receiving means formed preferably constituted by a foil cassette for unprinted foil and preferably at least one receiving cassette for printed foil, in the case of which the foil to be printed onto an unexposed or blank printing plate is able to be taken from a foil receiving means by means of a moving vacuum frame, is able to be moved onto the blank plate on the plate table and after exposure is able to be discharged, preferably into a receiving cassette, a higher throughput rate and a gentle handling of the foils etc. with a high standard of accuracy are possible by the provision of a plurality of vaccuum frames, of which at least two are attached to the periphery of at least one frame carrier, which is able to be turned through the angle between the vacuum frames, such attachment being a points which are offset from each other by the length of the path between the at least one foil receiving device and the plate table.

Device for producing printing plates

To increase the operating speed of a printing machine in which sheets are fed from a make-ready table (5) to a printing system (P, G; 2, 3, 65, 63), sheets are fed to the make-ready table in a transport direction and a lateral force is applied to the sheets as they are being fed to the make-ready table, for example by inclined belts (6-9). A feed roller, operating at a rotationally non-uniform speed, accelerates sheets gripped between the feed roller (18) and a counter roller (32) and the accelerated sheets then impinge on front register stops (50; 59) on either a transfer cylinder (34) or the impression cylinder (60) itself, the transfer cylinder or the impression cylinder, respectively, being driven at rotational non-uniform speed, first slightly slower than the accelerated speed of the sheets to ensure gentle impingement on the front register stops of the transfer cylinder or the impression cylinder, and then, after being gripped, the respective cylinder accelerates to a speed which , for the transfer cylinder, will be the same as an associated impression cylinder or, for the impression cylinder itself, to the same speed as the cylinders of the printing system.

Sheet transport arrangement for printing machines

To permit continuous adjustment of a groove cover element (15), the groove cover element is extended in the groove, formed with a through-bore (14) in which an eccentric cam (7) is located, which can be rotated by a spindle. By rotating the spindle, the cover element is raised from the groove, or lowered against a rubber blanket, printing plate or the like thereon. The spindle can be locked in rotated position by a counter nut (FIG. 1) or can be free to rock continuously during rotation of the cylinder by linking the spindle to an arm which rides on a fixed cam. The cam can be adjusted so that the position of the spindle, and hence of the groove cover element, will be flush with the cylinder just at the time when the cylinder rolls off against an adjacent cylinder (100). Adjustment of the cam can be manual, for example via a worm gear drive, or electrically, for example by a stepping motor, so that automatic speed-dependent positional adjustment of the cam is possible.

Printing machine cylinder with adjustable groove cover element

For smoothing of the leading edges of sheets disposed on the feed table of a sheetfeeder for a rotary printing machine, a vertically reciprocable rule (3) is provided. Prior to grasping of each sheet by grippers (16), the rule is lowered onto the sheets on the table (1), thereby ironing out waviness, so that the sheets may be evenly and securely grasped by the grippers (16) and correctly fed into the printing machine. In order to position the rule as close as possible to the leading edge of the sheets, the rule has recesses (5, 6) which accomodate the grippers (16) and front gauges (17).

Sheet smoother for the gripped edge of the sheet in a sheet-fed rotary

To provide for versatile printing, while permitting exchange of the plate of a blanket cylinder - plate cylinder couple during operation of the printing machine, i.e. while the machine is printing, for example only prime or verso printing in a single color, two blanket cylinder - plate cylinder (2, 4; 3, 5) are provided, selectively engageable with an impression cylinder (1). One (3) of the blanket cylinders is positionable in three axial positions, selectively (a) for engagement with the impression cylinder (1), (b) for engagement with the other blanket cylinder (2) or (c) removed from both the impression and the blanket cylinder, to permit exchange of the plate of the associated plate cylinder (5). A paper web substrate (6) can be passed, selectively, between the two blanket cylinders and partially about the impression cylinder, or between the impression cylinder and one of the blanket cylinders.

Versatile printing machine system permitting plate change during machine

For smoothing an ink film on an ink application roller, so that the ink film on the application roller which is also applied to the plate cylinder will be free from valleys, ridges, striations and the like, a plate-like stamp element (11) is engaged against the circumference of an ink application roller (9), preferably the last one in the direction of rotation of the plate cylinder (10). Preferably, the plate-like stamp element oscillates or reciprocates axially, and is engaged on the surface of the ink application roller (19) by an adjustable spring force (17, 18).

Printing machine ink smoother

A job strip encoding printing process data is disposed on an indicia-free zone of an associated printing plate. The printing process data include process control data, press presetting data and organization data for the entire print order using the associated printing plate. Preferably, all of the important printing adjustments are computer controlled and the printing machine includes a scanner for automatically reading the job strip when the printing plate is clamped onto the plate cylinder of the printing machine. The job strip is not integral with the printing plate so that the printing process data are easily changed. The job strip, however, is attached to the printing plate and therefore the printing process data and associated printing plates are not mixed up in the print shop. The job strip is elongated and aligned parallel and adjacent to a longitudinal edge portion of the printing plate which is clamped to the plate cylinder. The job strip is circumferentially displaced from but located close to the area of the printing plate which is capable of printing and which engages the blanket cylinder, so that the inking rollers roll over the job strip during printing to keep it clean for scanning.

Storage and retrieval of printing process data encoded on a printing

Register of sheets being transferred by a reversal drum (9), having suction grippers (16) to grip the trailing end (15) of a sheet (12) being transported and reversed between two printing stations (1, 2) is improved and assisted by positioning pricking pins (17) in or on the suction grippers (16), to prick into and engage the trailing end portions of the sheet being picked off an impression cylinder (5) of a first printing system (1) by the reversal and transport drum (9).

Rotary printing machine with sheet reversal and transport apparatus

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. The slot, or at least the central portion (11) thereof, can be slightly inclined with respect to a central axis (A-A) of the cylinder about which the blanket is to be stretched.

Rubber blanket attachment arrangement for an offset rotary printing

To facilitate insertion of a rubber blanket into the groove or slot (2) of a blanket cylinder (1) of a printing machine, and to reduce the width of the opening (3) leading to the groove or slot, the thickness of the blanket is reduced in the end portion (11, 12), for example by removing a portion of the rubber blanket material; a reinforcement strip (14, 15, 20) is bonded to a textile substrate (9) on which the blanket layer (10) is applied, preferably at the side opposite of the blanket layer only. The end portions (11, 12) are formed with zones of reduced thickness, for example in the form of cut-outs in the textile substrate and extending into the rubber layer, to permit insertion of an inserting tool, such as metal strips, preferably in the form of tines (FIG. 4: 24) on an insertion fork (23), fitting into the reliefs or cut-outs (16, 17, 18), with clearance, to permit pushing the end of the blanket through the narrow gap (3) of the slot by engagement of the tines with the reinforcement strip (14, 15, 20).

Rotary printing machine cylinder blanket construction and insertion tool

To prevent buckling of a lowermost one, or a lower group of superposed webs being fed, in superposed relation to a common folding triangle or folding former (1), a driven supply roller (2) is provided which has its circumference formed with projecting pins (6) or the like, long enough to penetrate through the entire stack of the superposed web (8) as it runs over the supply roller, thereby feeding all the webs at the same speed to the folding former. Preferably, a hold-down roller (9) is provided, formed with a circumferential groove (10) aligned with the pins (6) so that the pins can penetrate through the webs and fit into the groove (10).

Folding apparatus for folding superposed multiple webs

To permit easy threading of a plurality of paper webs through rollers which have projecting pins thereof to provide for positive feed of the paper webs by perforating the paper webs, the pins are located such that they can be selectively positioned below a cylindrical generated outline defined by the largest radial dimension of at least one of the engagement rollers, for example by being selectively retractable (FIG. 1) within the outline of the cylindrical roller, or by being located (FIG. 2) in flutes or depressions of fluted rollers. If the pins are selectively retractable and projectionable, preferably, a positioning cone (5) is located within a hollow roller (1), the axial position of the cone being determined by an external hand wheel (23) which, over a rod (4), axially positions the cone, while including a rotation-isolating coupling (14-22) between the hand wheel and the rod (4). The rollers may be located upstream, or downstream of the folding former, or in both positions, thereby functioning as supply or pull-off rollers, respectively.

Longitudinal folding apparatus for traveling webs, particularly paper

To reliably hold a sheet in a rotary sheet-fed offset printing machine, a plurality of pin or needle-like projections (11), preferably held on a holding strip (12), are located transversely just behind or beneath the grippers. The sheet is pressed against the pins by the rubber blanket of the blanket cylinder, to impale the sheet on the pins; or, if the projections are located beneath the grippers, the grippers indirectly apply pressure on the sheet to impale the sheet on the projections. In another embodiment (FIG. 6), a pressure block (13) with a resilient engagement surface (14) presses the grippers on the sheet for also impaling the sheet on the pins or needles. The projections may also be formed as knife edges (FIG. 4). Alternatively, the printing line can be shifted forwardly (FIG. 5), so that the rubber blanket will engage the ends of the grippers.

Printing cylinder construction for sheet-fed offset rotary printing

To prevent the formation of ghosts as sheets are pulled off a delivery drum (1) by a transport chain arrangement, the gripper mechanism (3-6) on the chain transport is movably located thereon to impart forward movement to the gripped sheet in addition to the movement of the chain and so that tension on the sheet is continuously maintained. The mechanism for imparting said additional movement includes a holding bracket (12) secured to the chain (2) on which a carrier plate (13) is secured, the carrier plate being movable with respect to the holding bracket and retaining the gripper mechanism. The carrier plate can be moved by an angled cam follower lever (15) secured to the holding bracket and pushing the carrier plate, and hence the gripper mechanism, forwardly in the direction of movement of the chain when the cam follower lever is engaged by a suitably positioned cam.

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Augsburg, Germany

Hermann Fischer