Abstract: An inking arrangement for printing presses comprises an ink fountain member having at least one fountain-forming face for forming an ink fountain, an ink fountain roller defining an ink channel together with the fountain member and having an outer peripheral surface to be inked through the channel, a plurality of rollers for supplying the ink applied to the peripheral surface of the fountain roller to a printing portion, and a cleaning tank disposed below the fountain member. The cleaning tank is provided with a cleaning blade at least alternatively shiftable to a cleaning position in which the blade is pressed against the peripheral surface of the fountain roller, or to a stand-by position in which the blade is away from the fountain roller. The ink applied to the peripheral surface of the fountain roller through the channel is scraped off by the blade in the cleaning position and collected in the tank.

Abstract: An offset perfecting press is disclosed which has a pair of blanket cylinders on opposite sides of a web traveling along a predefined path. Bearing different images to be printed, two plate cylinders are disposed in circumferentially spaced apart positions on each blanket cylinder. Each plate cylinder is independently movable between an image transfer position, where the plate cylinder is held to the blanket cylinder in order to print an image thereon for subsequent transfer to the web, and an image nontransfer position where the plate cylinder is spaced from the blanket cylinder. Only one plate cylinder is held in the image transfer position on each side of the web. For a change from one image to another, the plate cylinders that have been printing the opposite sides of the web are retracted to the image nontransfer positions, and the other plate cylinders, rotating in phase with the blanket cylinders, are moved to the image transfer positions. There is no need for stopping the web or the blanket cylinders.

Abstract: A method and a device for detecting and controlling the printing pressure for a flexographic machine having at least one printing group comprising first ink supply means, a second cylinder capable of removing a quantity of ink from said first supply means, a third cylinder rotatable and provided on its periphery with at least one covering element, the peripheral surface of which is defined by portions reproducing the motif to be printed, and a fourth cylinder defining, together with the third cylinder, a passage for the transit of a strip of material on which printing is to be performed; the cylindrical surface of the third cylinder has connected to it at least one sensor element for emitting signals proportional to the forces with which the sensor element itself is stressed during the course of contact of the portion of the third cylinder with the strip and with the second cylinder.

Abstract: An on demand ink mixing system for a flexographic or similar printer utilizes a chambered doctor blade with a chamber divided by a flexible bladder to form ink chamber and a pressure chamber. Ink use is coordinated with print run length, and ink mixing and the collapse of the ink chamber to essentially zero volume are coordinated to coincide with the end of the run. The flexible bladder is also utilized in the operation of the ink cleaning system to move cleaning solution through all portions of the supply system and printer contaminated by ink mixed for the run.

Abstract: For determining the ink coverages of printing inks involved in printing in one pixel of a print image, the pixel is scanned photoelectrically in the visible range of the spectrum and also in the near infrared range. Color coordinates of a perceptually approximately equidistant color system and at least one infrared value are formed from the scanned signals thus obtained. The ink coverages of the printing inks involved in the printing are then calculated from these color coordinates and from the minimum of one infrared value and are allocated to the pixel.

Abstract: The invention provides a method for controlling a plurality of ink control devices on a printing press, wherein the press operates to repetitively print an image on a substrate. The ink control devices each control the amount of ink supplied to a respective ink key zone on the substrate. The method includes the step of measuring color values for a plurality of areas of a selected image printed on the substrate to produce an acquired image array. Next, the acquired image array is aligned with a target image array comprised of target color values for the plurality of areas. The acquired image array is compared to the target image array on a pixel by pixel basis. A matrix equation is determined that links ink control device adjustments to changes in color values of the image printed on the substrate via sensitivity factors for each of the plurality of pixels. A least squares solution to the matrix equation is obtained to determine ink adjustments for each ink key zone.

Abstract: A method is disclosed for correction of the effects of ink back-flow and lateral flow in the inking system of a web-offset printing press. A plate coverage equation dependent on plate coverage is used to compensate for ink back-flow into the ink reservoir. An ink key distribution function is utilized to correct for the blurring effects of lateral ink spread caused by the action of vibrator rollers. A correction is also made for the ink saturation effect. The method is applicable to an ink key preset system.

Abstract: An ink duct for rotary printing presses with zone-wide metering elements disposed side by side and adjustable a variable spaced distance from an ink duct cylinder, each of the metering elements having support and metering regions disposed in the axial direction of the ink duct cylinder, the support regions resting independently of one another, under spring pressure, at least indirectly on the ink duct cylinder, and the metering regions extending in a wedgelike manner, the metering elements being swivelably supported and being coverable by an elastic foil secured to the ink duct, comprising support bodies disposed on the metering elements at both sides of the metering regions, the metering regions being cylindrical and being formed on the metering elements, the support bodies having a circumference formed with a flattened contact surface portion by which the support bodies at least indirectly rest, under the spring pressure, on the jacket surface of the ink duct cylinder.

Abstract: A retractable in-line inking/coating apparatus can apply either spot or overall inking/coating material to a plate and/or a blanket on the first printing unit or on any consecutive printing unit of any rotary offset printing press. The inking/coating apparatus is pivotally mounted within the conventional dampener space of any lithographic printing unit. The aqueous component of the flexographic printing ink or aqueous coating material is evaporated and dried by high velocity, hot air dryers and high performance heat and moisture extractors so that the aqueous or flexographic ink or coating material on a freshly printed or coated sheet is dry and can be dry-trapped on the next printing unit.

Abstract: An apparatus for inking the fountain roller of a press. A main body has a longitudinal extent substantially equal to that of the fountain roller, a blade holder disposed beneath and attached to the main body. The main body and blade holder combine to provide several ink channels of narrow width, with the channels terminating in spreader portions. There is a blade in the blade holder which extends to a position adjacent but not touching the fountain roller.

Abstract: In order to control ink application in a printing press, a sheet (3) printed by the printing press (1) is colorimetrically measured in a number of pixels (4) with respect to a selected color coordinate system that has been expanded to be four-dimensional by also taking into account an infrared component. Color difference vectors with respect to the desired color vectors, predefined or determined from a reference sheet (3) and referred to the same color coordinate system, are computed from the color vectors obtained for each pixel (4). A sensitivity matrix is determined for each measured pixel (4) of the sheet (3). The pixels (4) are classified by sensitivity class.

Abstract: A master chart comprises a representation of various blocks (1) of color produced by suitable combinations of the base colors cyan, magenta, yellow and black (C,M,Y,K) . There are also illustrations of color prints (2) which are to be printed by a copying machine onto a sheet. For the color standardization procedure test sheets are provided onto which the images from the master chart are to be printed. These carry the same array of color blocks (1A) and picture representations (2A) but the block and color representations are offset with respect to the positioning of the corresponding blocks on the master chart. The operator compares the various color blocks against one another and make an estimation as to what adjustments are needed to the copier to ensure that a more acceptable print is achieved.

Abstract: A fixed cutoff press is adapted to a variable cutoff press while maintaining the size of the blanket cylinders. A plate cylinder is mounted on a frame and includes a plate cylinder sleeve and a blanket cylinder is mounted on the frame, includes with a gapless blanket cylinder sleeve. The gapless blanket sleeve contacts the plate cylinder sleeve at a first nip. The press has an impression plate mounted on the frame in the case of a non-perfecting press or an identical, mirror image assembly of plate and blanket cylinders in the case of a perfecting press. A material to be printed passes through a second nip. Inkers are provided for transferring an ink film to the plate cylinder sleeve, the ink pattern being subsequently transferred to the blanket cylinder sleeve at the first nip and the ink pattern being subsequently transferred from the blanket cylinder sleeve to the material to be printed at the second nip.

Abstract: A shaftless rotary printing press includes a plurality of individually driven printing stations and at least one separately driven folding unit. The drives which work with one folding unit in one rotation are connected to a drive control unit by a control and parameterization bus and to a device for generating a setpoint and a synchronization signal by means of a parallel synchronization bus, and the drives are each connected to the synchronization bus, which is designed as a ring bus by a bus interface. This yields a rotary printing press without shafting which is so flexible that its printing stations can be synchronized with any desired folding unit from one production to another simply and inexpensively.

Abstract: In a process for assessing the quality of a print image produced on a printing material in a multi-color printing process, in which signals which reproduce print-image elements are generated with an image-recording arrangement, in which color values are derived from the signals for every print-image element, in which the color values are transformed into color measures of a predetermined color space, in which color distances between an actual color site and a desired reference color site are determined for the print-image elements, correction variables of the control elements (18, 19, 20, 21), whose effect on a control element (18) would cause the actual color sites to be as close as possible to the reference color sites, are calculated from the color distances and stored in memory, that the color-distance vectors (.DELTA.L.sub.Bn, .DELTA.a.sub.Bn, .DELTA.b.sub.Bn) and color distances (.DELTA.E.sub.Bn) of at least one predetermined reference image (B.sub.

Abstract: The present invention is an apparatus for setting printing pressure in an offset printing press having an impression cylinder, an eccentrically journaled blanket cylinder, and an eccentrically journaled plate cylinder, each of the cylinders and each of the eccentric journals having an axis, wherein the printing pressure is to be adjusted between the blanket cylinder and the impression cylinder, as well as between the blanket cylinder and the plate cylinder, wherein a bearer ring to bearer ring contact exists between the blanket cylinder and the plate cylinder, wherein the impression cylinder, the blanket cylinder and the plate cylinder are in a basic printing position in which the axis of the plate cylinder, the axis of the eccentric journal of the blanket cylinder are disposed on a first straight-line, and the axis of the blanket cylinder is disposed on a second straight-line intersecting with the first straight-line at the axis of the eccentric journal of the blanket cylinder, at an adjustment angle between

Abstract: Sheet-fed printing press with flat sheet guidance, having two endless conveyor belts for rectilinear, intervention-free movement of gripper carriages through printing units of the press, includes a device for adjusting the length of the conveyor belts, and a device for synchronizing the speeds of the conveyor belts and of the cylinders of the printing press, the length-adjusting device being made-ready for matching the belt lengths automatically to the cylinder circumference during operation, each of the conveyor belts having associated therewith its own drive and its own mechanism for synchronizing the speed of the respective conveyor belt with the respective cylinders independently of the other one of the conveyor belts, and method of synchronizing the sheet travel with the cylinders of the press.

Abstract: A doctor blade arrangement for a rinse inking unit of a rotary printing machine consists of a doctor blade carrier formed by a profile strip with a groove type recess. Two doctor blades adjustable at an inking roller are fixed on the doctor blade carrier almost like a roof and parallel to each other. The two doctor blades together with the inking roller, the groove type recess of the doctor blade carrier and sealings materials provided for the same at the end side border a dye chamber. In order to assure a good sealing of the dye chamber against the outcoming dye, the groove type recess is provided with a central middle part forming a main chamber and end-side side parts forming secondary chambers, which are connected with the main chamber through throttle gaps. The tube feeding the dye leads into the main chamber. The side parts are provided with the pipe lines discharging the dye and with the exhaust holes.

Abstract: A printing machine is disclosed, in particular a sheet-fed offset printing machine, in which a plurality of cylinders are coupled to one another via a continuous drive train, and at least two cylinders include a controllable drive. The controllable drive stresses the drive train in order affect the tooth-flank contact of the gear train, which affects the angular position of the printing cylinders. By controlling the angular positions of the printing cylinders, precise registration is maintained during dynamic changes in the load on the gear train during the printing process. More specifically, blanket cylinders in the printing machine are each coupled to a position-controllable drive, which is controlled by applying a preferred position value in such a way that the gear train placed between two drives is stressed by a predefined angular amount.

Abstract: A mixing and dispersing apparatus for emulsion ink in a printing press is disclosed. The apparatus includes a vessel having walls defining an upper chamber and a lower chamber. A motor drives a shaft carrying a propeller having pitched blades, disposed in the upper chamber. The shaft also carries a rotor disposed below the propeller. The rotor includes downwardly extending teeth that are disposed adjacent to inner and outer stator walls. The inner and outer stator walls are perforated by slots therein and are fixed with respect to the vessel. The propeller mixes ink and fountain solution and propels the mixture downward toward the rotor, which shears and disperses the ink and fountain solution into the lower chamber, forming a suitably stable emulsion ink. The emulsion ink is then pumped to an ink distribution rail for use of some of the emulsion ink for printing, with the remainder of the emulsion ink being recirculated to the mixing and dispersing apparatus.