Abstract: In a method for processing signals in an electronic engraving machine for engraving printing forms, in particular printing cylinders used for rotogravure, an engraving control signal is obtained by superimposing engraving data, representing tone values between “white” and “black” which are to be engraved, with a periodic screen signal for generating a gravure screen. The engraving control signal guides the lifting movement of the stylus of an engraving element. As a result of the lifting movement of the stylus, a series of cups arranged in the gravure screen is engraved on the printing form. To compensate an incorrect lifting movement of the stylus (rebound effect, lag effect), the engraving data undergo digital filtering before superposition of the gravure screen.
Type:
Grant
Filed:
February 28, 2000
Date of Patent:
July 27, 2004
Assignee:
Hell Gravure Systems GmbH
Inventors:
Dieter Fangmeyer, Christian Wiechering, Bernd Lübcke
Abstract: An apparatus for imaging a media is able to accommodate, in an imaging position, a drum for loading flat sheets of media or a mandrel for loading sleeve media. The apparatus includes a storage position for locating the drum or mandrel when not in use and provides mechanisms for safe transport of the drum or mandrel between the storage and imaging positions.
Abstract: In a method for operating an engraving member in an electronic engraving machine to engrave printing forms, especially printing cylinders for intaglio printing, a stylus of the engraving member is controlled by an engraving signal and engraves a sequence of cups arranged in a gravure screen in the rotating printing cylinder. The engraving signal is formed by superimposing the image signal representing the tone gradations to be engraved. In order to obtain good quality engraving, the engraving member is heated to a temperature that is close to operating temperature before engraving starts and/or during an interruption of engraving. For this purpose, the engraving member is driven with a periodic signal whose frequency is preferably located inside the ultrasonic range in order to avoid noise disturbances.
Abstract: A semi-digital printer includes a print head assembly that prints an image on a sheet of paper that has been mounted onto a turntable, and a rotating means which rotates the turntable so that the print head assembly ejects ink or toner onto the sheet of paper at one or more predetermined angles. The printing may be halftone or color. If the print head assembly includes more than one print head, the rotating means rotates the turntable to a different angle for each print head. By rotating the turntable in this manner, the printer records an image at any angle (0° to 360°) precisely (i.e., without having to perform the angular approximations required by conventional digital printers). As a result, a printed image of improved quality is produced. Alternatively, the semi-digital printer may be configured so that the print head assembly rotates relative to the paper.
Type:
Grant
Filed:
December 9, 1999
Date of Patent:
May 18, 2004
Assignee:
International Business Machines Corporation
Inventors:
Marco Martens, Ravishankar Rao, Gerhard R. Thompson, Charles B. Tresser, Chai W. Wu
Abstract: An engraving element of an electronic engraving machine for engraving printing cylinders as a shaft oscillating with small rotational angles around the longitudinal axis, a restoring element, a shaft bearing, a damping mechanism, a drive for the shaft, a lever-shaped stylus holder attached to the shaft, and an engraving stylus as a cutting tool. For engraving cups, the engraving stylus executes a stroke motion in the direction of a rotating printing cylinder. The engraving element is arranged with respect to the printing cylinder rotating around the rotational axis such that the shaft of the engraving element proceeds substantially parallel to the rotational axis of the printing cylinder, and the stroke motion of the engraving stylus occurs in a plane oriented perpendicular to the rotational axis of the printing cylinder. As a result, a better geometry of the cups is achieved in the engraving.
Abstract: An imaging device for setting an image on a printing form by at least one imaging energy source, includes a device for determining a component of a relative movement between the imaging energy source and the printing form whereon an image is to be set. An actuator device moves the imaging energy source in such a manner that undesired components of the relative movement between the imaging energy source and the printing form are reduced. An imaging module may be formed of at least two of the imaging devices. A printing press includes the imaging device or the imaging module. A method sets an image on a printing form.
Abstract: In a device for extracting processing residues for a processing apparatus having a plurality of processing units preferably movable along a processing path, particularly for an engraving machine having a plurality of engraving supports, an admission opening of an extraction conduit is allocated to each processing unit. The device has a collecting main for the extraction. For this purpose, the collecting main is preferably designed as an extraction channel, and the end of each of the extraction conduits facing away from the processing unit comprises a mouthpiece that discharges into the extraction channel, namely preferably into an admission slot of the extraction channel, whereby it is movable along and in the admission slot.