Heidelberger Druckmaschinen Ag

Bernd Kistler

Werner Huber

Wolfgang Geissler

Harald Bucher

Helmut Kipphan

Clemens Rensch

Gerhard Fischer

Gerhard Loeffler

Anton Rodi

Nikolaus Pfeiffer

Manfred Schneider

Hans-Peter Grossmann

Guenther Uhlig

A method of regulating inking when printing with a printing machine, including determining an actual color value with a color measuring device directed towards a printed material, and feeding the determined actual color value to a color control device, comparing the actual color value with a desired color value, forming an adjusted variable from the comparison value by using a mathematical model of the ink control loop, and feeding the adjusted variable to an ink setting element so that the setting element correctingly changes the inking, which comprises calculating a steady state value (s ) from an additive superimposition of the time changes in preceding adjusted variable changes (&Dgr;y ), and calculating a new adjusted variable (y) from the desired color locus (x ), the actual color value (x ) and the steady state value (s ).

Method of regulating inking when printing with a printing machine

A device for inspecting a printed image of a product of a printing press, comprising an image detecting device that furnishes actual image data of the product, and a comparison circuit comparing the actual image data with master image data from a defect-free master image, dividing means for performing a preselectable division of the printed image into inspection areas, and wherein if a defect is detected by the comparison circuit the associated inspection area is designated as being defective.

Device for image inspection

A method for image inspection and color guidance for printing products of a printing press, in which in on-line operation, actual image data of the printed images of the printed products are obtained and compared with nominal image data for the purpose of locating image defects, which comprises the steps of checking, upon the appearance of a defect, before any change in the ink feed is made, as to whether on the basis of the type of defect, some other cause than the color guidance for the deviation is possible.

Method for image inspection and color guidance for printing products of a printing press

A process for controlling coloration in multicolor printing, wherein a photoelectric measuring arrangement (,) is used to obtain actual color measurement values from the printed image (,), wherein the actual color measurement values are compared with specified setpoint color measurement values, and wherein the comparison signals are supplied to a color controlling device (,), with the layer thickness of the ink to be applied to a material to be printed (,) being controllable by means of color controlling elements (,), monitoring signals are continuously derived at selected measuring locations (,), whereby the number of the measuring locations (,) is increased if the monitoring signals exceed a specified threshold value and the actual color measurement values obtained at the increased number (N,) of measuring locations (,) are processed into comparison signal. The invention can be used in multicolor printing machines.

Process for controlling coloration in multicolor printing

A method for regulating inking of a printing press. The method includes a first step of providing a picture taking device, a closed-loop control device, and a printed product having a surface with a printed image. A second step of printing a print control strip on the surface next to the printed image. A third step of deriving first picture signals from the print control strip and deriving second picture signals from the printed image with the picture taking device. A fourth step of using the closed-loop control device for deriving actual values representing inking of the print control strip from the first picture signals and comparing the actual values to desired values for deriving resultant comparison values. A fifth step of determining ink adjusting signals for controlling ink distribution devices from the resultant comparison values for varying inking of the print product until a desired value is reached during a printer tuning phase. A sixth step of generating an OK signal when the desired value is reached. A seventh step of using the closed-loop control device for deriving further actual values representing inking of the printed image from the second picture signals and comparing the further actual values to further desired values for creating further resultant comparison values. Lastly, one determines further ink adjusting signals for controlling the ink distribution devices from the further resultant comparison values for varying inking of the printed product.

Method for regulating inking during printing operations of a printing

Process and arrangement for controlling or regulating operations carried

The invention relates to a method for controlling or regulating the coloration in a printing press, in which color metering elements are adjusted with the aid of a control or regulating device, and in which by means of at least one image pickup device associated with the printing press, picture signals are obtained continuously from the printed image and supplied to the control or regulating device. Provision is made so that a plurality of control or regulating algorithms are available for selection to the control or regulating device, and from among these algorithms, as a function of predeterminable parameters, a control or regulating algorithm is automatically selected and used.

Method for controlling or regulating the inking in a printing press

A method for controlling inking during the printing process, in particular during the production run, in a printing press, the printing press having an imaging device coupled to a computing device operative for collecting image color measurement data from the imaging device, and numerically processing the image data, and in which color measurement data are obtained from printed images produced on an continuous basis, these data being used for control or regulation to influence image inking if a predetermined image color tolerance is exceeded, the method which comprises the steps of collecting the image color measurement data, over time using the image color measurement data for computing a color trend estimate; evaluating the color trend estimate and performing a corrective control of the inking if the color trend estimate data indicate that image coloring will move outside the allowable image color tolerance.

Method for adjusting the inking in a printing press

A method for regulating inking when printing with a printing press, which includes, by means of at least one sensor element directed towards the surface of a recording carrier at a given measurement site, deriving actual-value signals from at least one physical variable representing the inking; comparing the actual value signals with reference-value signals for the physical variable at the same measurement site; deriving, in accordance with a prescribed principle, control signals for control elements for the physical variable from the comparison-value signals obtained, and feeding the derived control signals to a control element; and placing the actual value in a range of reference values by means of the control element and holding it there automatically; further includes acting upon the control elements with defined control signals during a startup phase of the printing press; obtaining actual-value signals from a multiplicity of measurement sites in the entire printed surface of the recording carrier; determining, for each physical variable to be controlled and for each measurement site, changes in the actual-value signals with respect to the control signals to be defined; selecting measurement sites wherein the changes occur most markedly; and regulating the physical variables exclusively at the selected measurement sites, in a production-run phase of the printing press.

Method for regulating inking when printing with a printing press

Method of regulating inking when printing is performed with more than three printing colors, which includes comparing, in a control, actual value color locations derived from a color measuring arrangement with reference value color locations in a given user color space; deriving control signals from the attained comparison values, in accordance with a predetermined relationship, for an inking device containing ink distribution devices which influence the thickness of a layer of printing ink applied zonally in the form of halftone dots or solid full-tone areas to a material to be printed; and further deriving the actual value color locations from measurement locations in the printed image. When printing with n printing colors wherein n is greater than 3, deriving the actual value color locations from measurement locations of at least (n-2) regions, wherein vectors of area coverage of all of the n printing colors involved are, respectively, linearly independent of one another.

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Eppingen, Germany

Bernd Kistler