Patent ID: 6950212
Filing Date: 2005-09-27
Classification: B41C,H04N

Abstract:
1. A method for producing and evaluating a sample cut in a electronic engraving machine for engraving printing forms for rotogravure, comprising the steps of: forming an engraving control signal for driving the engraving stylus of an engraving element from engraving data which represent rated gradations between “light” and “dark” to be engraved and from a periodic raster signal for generating an engraving raster; providing a sample engraving before actual engraving of the printing form, wherein sample cups are engraved for predetermined rated gradations; producing a video image of the sample cups engraved in the sample engraving; for measuring geometric parameters of the engraved sample cups, selecting an engraved sample cup in the video image for one of the predetermined rated gradations as a reference location in an XY-measuring system allocated to the video image; dependent on the raster parameters of the engraving raster, defining measuring locations for measuring the geometric parameters of the sample cups in the video image as coordinate-related spacings from the selected reference location; measuring the geometric parameters of the sample cups at the determined measuring locations by interpreting the video image, and comparing them to the geometric parameters that define the predetermined rated gradations; deriving setting values from the comparison with which the engraving control signal is calibrated such that the engraved actual gradations correspond to the rated gradations to be engraved; with the engraving stylus engraving a sequence of cups arranged in the engraving raster engraving line by engraving line into the printing cylinder, geometric parameters of the cups defined engraved, actual gradations; and with the engraving element implementing a feed motion directed in an axial direction of the printing cylinder for planar engraving of the printing cylinder.