Abstract: A method is disclosed for determining ink key control settings for a plurality of ink keys in a printing press. Each of the ink keys controls the amount of ink supplied to a roller and then to a respective ink key zone on a substrate to print an image. A press model relates image requirements to ink key control settings. The press model includes a gain and a respective offset associated with each ink key. The offset represents the amount a value represented by the ink key control setting varies from the actual ink key opening. The drift in the respective offsets of the ink keys is tracked by comparing control settings predicted by the press model with final control settings after a press job has been satisfactorily completed.

Abstract: A method for providing indications for conditioning ink flow valves of at least one inking unit of a printing press. The printing area of the inking unit is divided into a multiplicity of inking zones each supplied by one ink flow valve in order to prescribe a predetermined rate of ink flow for each ink zone in said at least one inking unit. The method includes determining by calculating, from a digital image being processed for printing, a representative ink density value for each ink zone and for each color separation and furnishing the ink flow valves respectively with the values for regulating the flow in the ink zones.

Abstract: A register control device for the cylinder of a printing machine that emits a signal when a printing plate is resting in register on one or more register pins associated with a print cylinder. The signal is communicated to a stationary evaluation unit by a magnetic field. In this regard, a magnetic field sensor is attached to the printing machine frame and is used to detect the signal and forward the signal to the evaluation unit. The evaluation unit uses the communicated signal to determine whether or not insertion of the printing plate was properly performed.

Abstract: A dampening train of rollers in an offset printing press system for delivering dampening solution to a plate cylinder in which the dampening train of rollers is independent of and separate from an inking train of rollers which provide ink to the plate cylinder. The dampening train of rollers has at least four rollers including a dampening solution transfer roller, a dampening form roller, a single mechanically driven drive roller, and at least one rider roller. The plate cylinder engages with the single dampening form roller which transfers an even application of dampening solution to the plate cylinder. The mechanically driven drive roller is surrounded by the dampening form roller and the rider rollers which are positioned at the supply side of the drive roller between the transfer roller and the form roller.

Abstract: Method for metered transferring of ink to an ink roller in a printing unit of a rotary offset printing press, wherein the ink is applied under pressure to a casing surface of the ink roller, includes determining digital data for effecting a two-dimensional ink distribution on the casing surface corresponding to an ink consumption. The ink is ejected in droplets from an ink-jet unit to the ink roller. The ink-jet unit has nozzles which are aligned with one dimension of the two-dimensional ink distribution. The ink-jet nozzles of the ink-jet unit are controlled by a control device in accordance with the digital data.

Abstract: A retainer for holding a printing plate to the cylindrical surface of a vacuum drum has a curved surface which conforms to and seals against the cylindrical surface of the drum. The retainer is held in place by pressure differential. An edge portion of a printing plate is received below a lip which extends along the retainer. The retainer is light in weight and therefore does not significantly unbalance the drum even if it is not always in the same position on the drum. The retainer is also inexpensive to manufacture and less likely than prior art clamps to cause damage if it fails.

Abstract: Several printing units are arranged in a row for printing on as many separate webs traveling in centerline alignment and in phase with one another. At least one preselected web, on issuing from one printing unit, is directed over an angled guide rod thereby to be turned 90 degrees out of phase with the other, unselected webs. Subsequently traveling over a triangular shaped former, the preselected web is folded along a centerline thereof, back into phase with the unselected webs. The preselected web, already formed, and the unselected ones, yet unfolded, are then all superposed one upon another, with the fold of the preselected web in register with the aligned centerline of the unselected webs. The superposed webs are then folded by another former along the aligned centerline of the unselected webs. Subsequently fed into a cutting and folding device, the webs are cut and folded transversely into individual multiple-page signatures each having one center spread in addition to the usual inmost center spread.

Abstract: A sheet of elastomeric material that serves as a shock absorber and cushion for use between a flexographic printing plate and a printing cylinder during printing for compensating for variations in thickness, height and centricity of the printing cylinder and flexographic printing plate to prevent distortions in the image being printed that includes providing an elastomeric sheet having a longitudinal direction in the direction of circumferential travel of the cylinder circumference that includes a plurality or array of protrusions formed of the elastomeric material of predetermined cross-sectional shape and area and the material having a durometer to cushion the flexographic plate in such a way to provide the necessary compensation to ensure a high quality printed image at high speed.

Abstract: A device for fastening flexible printing plates to a plate cylinder of rotary printing machines having a channel in the plate cylinder which accommodates bent ends of the printing plate. A bore in the channel is axially parallel to the plate cylinder and has two segmented shafts arranged pivotably therein. Leaf springs are each fastened to the segmented shafts and can be brought into contact with the ends of the printing plate inserted into the channel. A region radially connects the bore to a channel gap on the periphery of the plate cylinder. The channel has lateral recesses at a distance from the channel gap and, the approximately rectangularly bent ends of the printing plate are equipped with shaped elements which project into the channel in the direction of the recesses. The shaped elements of one or both ends inserted into the channel can be moved into the recesses by bringing the respective leaf springs into contact while bending the ends.

Abstract: A method of correcting for malfunctioning ink ejection elements in a printing system comprising the step of (a) obtaining a standard printmask; (b) assigning to at least two ink ejection elements a probability that each of such at least two ink ejection element will work properly; (d) attempting to modify the standard printmask by replacing ink ejection elements having a certain probability to work properly with different ink ejection elements having a bigger probability to work properly, to create a modified printmask.

Abstract: The present invention is related to a printing unit including a frame (2) and an upper plate cylinder (12) mounted in the frame (2). An upper blanket cylinder (16) is in selective contact with the upper plate cylinder (12), and a lower blanket cylinder (18) forms a nip with the upper blanket cylinder (16). A web (8) passes through the nip. A lower plate cylinder (14) contacts the lower blanket cylinder (18). Impression setting means (60, 62, 82) are assigned to movable housings (40, 44) of the movable cylinders (12, 14, 16). The impression setting means (60, 62, 82) are provided to adjust forces exerted on bearers (20) of the printing unit cylinders (12, 14, 16).

Abstract: A printing apparatus (1001) having a plurality of blanket cylinders (1051 to 1054) normally-contacting to impression cylinders (1031, 1032), plate cylinders (1041 to 1044) normally-contacting to the respective blanket cylinders, and a ink coating apparatus (1061 to 1064), a printing apparatus, an imaging apparatus, an imaging method, an imaging medium, a printing system, and a printing method. In the printing apparatus (1001), a plurality of ink coating apparatus (1061 to 1064) is arranged in a substantially gravity direction, a feeding apparatus (1020) of sheets of recording mediums to the printing apparatus and a discharging apparatus (1070) are provided at a side opposite to a setting side of the ink coating apparatus with respect to the blanket cylinders. The printing apparatus can execute a back face printing easily, and has good workability.

Abstract: An apparatus for performing successively performable actuations in a printing press includes a pressure converter having an actuator formed with actuator surfaces which are successively able to be acted upon stepwise by pressure fluid; and a printing press in combination with the apparatus. Successively performed actuations in a printing press include switching or controlling, coupling, adjusting and tensioning operations, wherein machine or press parts are moved and/or held in a given position. Such actuations may be necessary in various devices of the printing press, a defined sequence of actuations having to be adhered to, depending upon the functions of the individual devices and to assure disruption-free cooperation of the devices. The actuations often require a transmission of comparatively strong forces to devices located at various places in the printing press which in terms of structural space are quite restricted. Pneumatic and hydraulic systems are therefore used for these purposes.

Abstract: A printing plate for an offset printing machine which comprises an electrically non-conductive material adapted for mounting on a plate cylinder of the printing machine and which has cuts in at least one area thereof adapted to cooperate with register pins arranged on the plate cylinder. An electrically conductive layer is arranged on the printing plate in the area of the cuts for making electrical contact with the register pins to facilitate proper mounting of the plate on the cylinder.

Abstract: A plurality of individual printing groups are arranged about the periphery of a counter-pressure cylinder in a multi-color printing unit. The plurality of printing groups can selectively be combined into dual printing groups. These printing groups can be spaced at an acute angle. Alternatively, the printing groups can extend in a vertical direction and are arranged closely or at a short distance from each other. Selected ones of these printing groups can be raised and lowered.

Abstract: A printing press includes a pair of in-line central impression cylinders which rotate about parallel axes. A web which is printed on the central impression cylinders is advanced from one of the cylinders to the other along a path which is perpendicular to the axes. The web is advanced from an unwind to the first central impression cylinder along a path which is parallel to the axes, and the web is advanced from the second central impression cylinder to a rewind along a path which is parallel to the axis. The web path between the central impression cylinders is relatively short, and the printed side of the web does not contact any rolls except possibly a laydown roll before the second impression cylinder. The central impression cylinders and the plate rolls are driven by different servo motors, and a controller controls the servo motors for adjusting the repeat of the printed images.

Abstract: A crank mechanism for use in a rotary printing press is capable of varying the crank stroke length while the rotary printing press is operating. A rotatable eccentric journal and an eccentric bushing are shiftable with respect to each other. A helical groove and a cooperating pin are used to shift the eccentricities of the journal and the bushing to vary the effective stroke length of the crank mechanism.

Abstract: A chill roller having in the interior thereof structural features selected from groups thereof consisting of mixing zones and transport pipes, and having at the exterior thereof a coolant supply pipe and a coolant discharge pipe, includes coolant supplied through the coolant supply pipe to the structural features simultaneously for forming a uniform temperature profile over the entire length of one of the chill roller and a surface of a cylinder jacket thereof; a chill roller stand having a plurality of the foregoing chill rollers; and a rotary printing press having the chill roller stand with a plurality of the chill rollers.

Abstract: A printing paste supply degree can stir up and knead past contained in a syringe extremely efficiently and extrudes the paste in a condition suitable for a screen printing through a discharge opening of the syringe. The paste supply device comprises a syringe made from specific resin and a mixer unit which is fitted on an inlet end portion of the syringe.

Abstract: To facilitate the attachment and adjustment of a printing plate on the outer surface of the plate cylinder of a printing machine, a layer of friction-reducing material is applied to the underside of the printing plate or the outer surface of the plate cylinder or both. The friction-reducing, sliding material may be a thermoset material, a thermoplastic material or an inorganic dry lubricant. The sliding material may be burnt into the supporting surface or bonded thereto by an adhesion promoting substrate layer.