Abstract: A method of avoiding register differences during the operation of a printing machine having a plurality of individual printing units includes counteracting, at least by circumferential register corrections, respective register differences in the individual printing units, determining the register differences for different printing speeds and storing them in a memory, and determining the various register differences at different printing speeds by an automatic register measuring and register control device and, in the event of changes in the printing speed, superimposing the previously determined magnitude of the register correction on the adjusted variable of the automatic register measuring and register control device; and a device for performing the method.

Abstract: The present invention relates to a method for controlling the ink feed in a printing press which processes printing substrates (12) and features at least one inking unit and one computer and to a device for carrying out the method. The present invention is characterized in that the computer knows at least the physical properties of printing ink and/or printing substrates (12) as data, that the stored data is read into an ink control model which is stored in the computer, and that the optimum settings with regard to the ink feed are made on the basis of this ink control model before the start of printing or during the printing process.

Abstract: Printing material is transported through the multicolor printing machine with a cyclically operating feeding arrangement. At least one surface of the printing material is successively imprinted with a printed image. The printed image is recorded in a image pickup and an image signal of each printed image is generated. The image signal generated from a plurality of printed images is transmitted to a control device. The control device processes the electric image signals to obtain information relating to rhythmic vibrations in the machine causing register deviations. The cause of the vibrations is determined and counter-measures are initiated for minimizing or eliminating the rhythmic vibrations.

Abstract: A method of avoiding register differences during the operation of a printing machine having a plurality of individual printing units includes counteracting, at least by circumferential register corrections, respective register differences in the individual printing units, determining the register differences for different printing speeds and storing them in a memory, and determining the various register differences at different printing speeds by an automatic register measuring and register control device and, in the event of changes in the printing speed, superimposing the previously determined magnitude of the register correction on the adjusted variable of the automatic register measuring and register control device; and a device for performing the method.

Abstract: The method effects a closed-loop control of the quantity of dampening solution during printing. The metering of the quantity of dampening solution to be applied to the printing material is preferably a function of the printing speed. In addition, at least one of the variables that influence the requisite quantity of dampening solution in the printing process is taken into account.

Abstract: A method is proposed for generating a color profile using the determination of a mapping A′ of a device-independent process space Q(m) of dimension m, m being a natural number, to a device-dependent process space K′(n) of dimension n, n being a natural number, for a first set of specific parameters, which is distinguished by the mapping being represented by a concatenation of mappings, which includes a known mapping A from Q(m) to a device-dependent process space K(n) of dimension n, n being a natural number, for another set of specific process parameters, which differs at least in one element from a first set of specific process parameters; and either of a mapping TK from K(n) to K′(n) or a self-mapping TQ by Q(M).

Abstract: First, the inking behavior of the printing units of a multicolor rotary printing machine is determined by means of test forms. The inking nonuniformities on the test forms are transmitted to the pre-press stage. Using the data about the inking nonuniformities of the test forms, the raster tonal values of the color separations of a printing form are modified in such a way that the inking nonuniformities are compensated locally on the basis of the location of their occurrence in the print on the printing forms or films.

Abstract: A method of setting guide elements for a flat material along a printing-material conveying path in a rotary printing machine includes determining a job-specifically optimized actuating position for a positioning of sheet-guiding elements and of sheet-conveying elements by using job-specific printed-image information known from a prepress stage. The sheet-guiding elements and/or the sheet-conveying elements are positioned in relation to a printed image by using the determined job-specifically optimized actuating position.

Abstract: A method for controlling the temperature of print bearer surfaces during printing in rotary printing machines. The print bearers are fastened in exchangeable fashion on the circumferential surface of print form cylinders. The surfaces of the print bearers are inked by inking form rollers. The temperature of the color-separation-guiding surfaces of the print bearers is controlled in such a way that narrower/broader printing and/or shorter/longer printing arising during the passage of the printed material through the printing unit is compensated per individual printing unit.

Abstract: A method of determining trapping, i.e., spreading or choking, in color boundary areas in a printed image, includes characterizing with respect to register behavior one of a printing machine and a printing machine type, respectively, performing a printing; determining the printing-machine specific register behavior with knowledge of influencing factors relating to the color to be printed and the printing material to be printed on for the job being printed; calculating minimum required spreadings and chokings, respectively, while taking a safety margin. into account; and taking into account minimum geometric overlaps in producing an original.

Abstract: A method of releasing a sheet from a blanket cylinder of a printing machine, wherein the sheet is guided by an impression cylinder and held by grippers thereof, includes moving, with respect to the impression cylinder, elements of the impression cylinder holding the sheet, in a direction relatively counter to the direction of rotation of the impression cylinder, so as to produce an enlarged pull-off angle after a leading edge of the sheet has passed a printing nip between the blanket and the impression cylinders; and a device for performing the foregoing method. The background to the invention is the knowledge that higher tensile forces on a sheet are disadvantageous, and the object was therefore set of making available a method and a device in which the tensile force is reduced. This is achieved by means of a method in which, in order to produce an enlarged pull-off angle (.gamma.

Abstract: A method for eliminating a rhythmic register error in a sheet-fed printing machine with a multiple-size sheet-conveying cylinder having at least one first and one second gripper device includes varying instants of closure of the gripper devices by adjusting adjusting devices assigned to the gripper devices so as to compensate for the register error; and a device for performing the foregoing method.

Abstract: Sheet delivery in a printing press, wherein, at acceptance of a sheet, a gripper bar of the delivery has a speed which is increased in comparison with a sheet-surrendering or transferring gripper bar includes delivery chains, and a drive for driving the chains so as to increase the speed of the gripper bar of the delivery at an instant at which a sheet is transferred to the gripper bar of the delivery by the sheet-surrendering gripper bar.