Man Roland Druckmaschinen Ag

Roland Offsetmaschinenfabrik Faber & Schleicher Ag

Mabeg Maschinenbau Gmbh & Company

Harry M Greiner

Claus D Simeth

Hermann Fischer

Roland Holl

Paul Abendroth

Kurt Difflipp

Peter Schramm

Klaus Neberle

Adolf Schwebel

Friedrich Preuss

Werner Kaiser

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

In accordance with the invention a varnishing unit in a printing machine is provided which simultaneously varnishes and perfects printing sheets. The varnishing unit comprises a rotating impression cylinder in contact with a rotating varnishing cylinder to create a nip between the two cylinders through which sheets are individually drawn. In order to perfect each sheet at the nip, the impression cylinder has at least one plate or a blanket secured to its surface. Depending on whether a plate or a blanket is secured to the impression cylinder, an appropriate dampening and inking means is provided. Similarly, the varnishing cylinder is supplied a controlled quantity of varnish by a varnishing means.

Printing machine for printing and final varnishing of sheets

The invention relates to a sheet feeder for the individual feeding of sheets to a sheet treating machine. A first sheet pile is carried by a main pile table, and sheets from this sheet pile can be fed by a sheet separating device, optionally via a first feed table, to the sheet treating machine. A further sheet pile is carried by an auxiliary pile table. Sheets can be fed by a second sheet separating device from this further sheet pile to the sheet treating machine, again optionally via a second feed table. Using this arrangement, in place of the sheets from the first pile table, sheets from the auxiliary pile table can be fed to the sheet treating machine without interruption, as the sheet feed from the two piles is carried out in the same rhythm. Preferably a control circuit is used to meter out a selected number of prerun sheets from the auxiliary pile table followed without interruption by another selected number of continuous running sheets.

Sheet feeder particularly for printing presses

A system for presetting register and color zone adjusting devices in a multi-color rotary printing machine uses digitally-driven optical scanners axially traversing the plate cylinders under control of at least one numerical computer. Machine-specific characteristics are programmed in non-volatile memory as referenced values. Data processing is not required to be conducted external to the printing machine. The system is compact and requires practically no re-adjustment or entry of desired values from the machine operator. The machine operator, however, may enter coordinates for printing areas on the printing plate in order to speed up the scanning process for determining the initial color zone preset. The scanner multi-functionally scans the printing plate for both register adjustment and for integrating the ratio of printing to non-printing area for each inking zone. The system is easily reprogrammed and the optical scanner is interchangeable with a densitometer in order to provide alternative control functions during printing, such as the regulation of inking and dampening.

Printing machine pre-setting arrangement

An automatic control method and apparatus for adjusting the register of printing plates in a multi-color printing press before test sheets or proofs are printed. Register marks are copied on the printing plates when the plates are manufactured. Photoelectric scanners sense the register marks and determine the relative positions of the printing plates without the use of paper. The positions of the printing plates are compared and the plate cylinders are adjusted so that the printing plates of all the plate cylinders are in register with one another. Preferably the relative positions are referenced to registered zero positions in the middle of the adjustment range for each plate cylinder, and the position of the printing plate having the least deviation from the corresponding zero position is chosen as a reference position to which the positions of the other printing plates are compared.

System for adjusting printing plates mounted on plate cylinders

An apparatus and method for checking and automatically correcting register adjustment of a sheet-fed printing press at the same time as remote densitometric measurement of an ink density check strip for ink fountain key adjustment. To read alignment marks printed parallel to the ink density check strip, a second optical sensor is mounted on the ink density scanner already used in practice to traverse and read the ink density check strip. A register control computer accepts the signal from the second optical sensor, detects the relative positions of the scanned alignment marks, compares the relative positions to each other and calculates axial, peripheral, and skew register adjustments. Position information is exchanged between the register control computer and the corresponding ink density control computer. The measured positions of the ink density check strip segments, for example, can be used in part to determine the positions of the register marks.

Method for production of impressions of accurate register on printing

An inking unit for a printing press including a source of ink, a set of ink transfer rollers for establishing an ink film, a distributor roller vibrated endwise for distribution of the ink film and a form roller for applying the ink film to a plate on the plate cylinder. The form roller has a shaft and an outer cylindrical shell, the latter being rotated by surface engagement. A bearing between the shaft and the shell permits relative axial as well as rotational movement. A cam of the cylindrical, or drum, type mounted on the shaft has an endless wavy groove in which is received a cam follower in the form of a roller extending radially inwardly from the sleeve so that the sleeve reciprocates through a single cycle as a result of a single relative rotation of the shaft. The shaft is driven at a speed which causes the frequency of vibration of the form roller to differ from the frequency of vibration of the distributor roller so that the ghost image on the form roller is constantly being displaced and dissipated both peripherally and axially with respect to the image on the plate resulting in substantially ghost-free printing. A clutch is provided for remote switching between two modes of operation.

Inking unit with traversing ink rollers

A washing assembly for a lithographic press including a washing roller having a porous resilient surface for carrying a charge of cleaning fluid, the washing roller being mounted in a frame for rocking movement from a disengaged position to a first washing position in which the washing roller is engaged with the surface of the blanket cylinder and a second washing position in which the roller is engaged with the surface of the impression cylinder. A drive wheel is provided at the end of the blanket cylinder for coupling to a driven wheel at the end of the washing roller as the frame is rocked to its first washing position for differential driving of the washing roller to produce relative wiping against the surface of the blanket cylinder. A squeeze roller in pressing engagement with the washing roller prepares the surface of the washing roller to accept a fresh charge of cleaning fluid. In the preferred embodiment as used in a 'five cylinder' press, first and second washing rollers are journaled on different portions of the same frame so that in the first washing position of the frame the washing rollers respectively engage the surfaces of separate blanket cylinders. The gap in the impression cylinder is spanned by a bridge to prevent the washing roller from falling into the gap.

Arrangement for washing cylinders on printing presses

A warning system for a printing press to warn the operator upon the exceeding, or departure from, a desired set of running conditions which includes a plurality of remote condition transducers which, in the simplest form of the invention, are in the form of switches. Coupled to the transducers are respective signal generators each of which generates an acoustic signal which has a distinctive quality as compared to all of the other acoustic signals. A loudspeaker common to all of the signal generators is audible at the control station. The distinctiveness of the signal serves to promptly inform the operator which of the running conditions has been exceeded so that corrective action may be taken. In a second embodiment of the invention the transducers produce output control signals which vary in magnitude with the condition, and the corresponding acoustic signal generator produces a signal having a distinctive first quality when the control signal exceeds a threshold level. In addition, each signal generator is made responsive to the magnitude of the control signal for imparting to the acoustic signal a distinctive second quality to a degree which depends upon the departure of the control signal from the threshold level and which is thereby indicative of the degree of urgency.

Warning system for printing presses

A mechanism for sorting sheets from a printing press to assure proper color density and to assist in making corrective adjustment which includes a main conveyor for normally conducting sheets to a main delivery pile and having a transfer station. An auxiliary conveyor extends from the transfer station to an auxiliary delivery pile. A scanning device is arranged upstream of the main conveyor for responding to the color density of the printed image on a passing sheet. A comparator produces a control signal when the color density is above or below tolerance, signifying a sub-quality sheet. Mechanism at the transfer station is triggered by the control signal so that the sub-quality sheet is diverted to the auxiliary conveyor for depositing on the auxiliary pile. The mechanism not only accomplishes sorting but the fact of diversion and the observed rate of diversion provides constant instruction to the pressman as to the necessity for, and the degree of, a corrective change in ink feed rate.

Apparatus for use on printing presses to insure optimum color density

A control system for optimizing the starting angle of a vibrating roller for production of an evenly distributed film of ink on the printing plate of a printing press, particularly an offset press, in which a reciprocating drive connection is provided between the press drive and the vibrating roller for reciprocation of the latter. A chart is provided for each one of a complete set of reference distribution starting angles for the vibrating roller, each chart showing for each starting angle a corresponding ink density distribution curve which, when matched to the observed ink density distribution in a printed product, provides direct reading of optimum starting angle. A variable phase changer is interposed in the drive connection leading to the vibrating roller for directly setting the starting angle to optimum value. In a preferred embodiment of the invention the charts are arranged angularly spaced on a rotatable carrier disc which is coupled to a first servo device, while the phase changer is coupled to a second servo device, the servo devices being coupled together by servo circuitry for angular coincidence at an angle which is manually set. When the disc is in reference position (for example, zero), the optimum starting angle is read off the chart, following which the disc and phase changer are set, simultaneously, to the optimum angle.

Device for determination of operating angle of distributor rollers

A spur gear formed of a laminated stack of axially thin spur gear elements having straight axially extending teeth identical involute tooth profiles and with means for securing them together in coaxial relation with stepped increments of phase between them producing a gear having a helical tooth pattern distinguished by the smoothness and lack of vibration of a helical gear while nevertheless avoiding the end thrust problems and the variations in phase which can occur with helical gearing.

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Offenbach am Main, Germany

Harry M Greiner