Abstract: In order to achieve good lateral sealing in a simple construction of a chamber doctor, side parts are drawn toward the end sides of the work blade by magnets and/or the side parts are resiliently deformable and contact the work blade with pretensioning.

Abstract: Dampening solution is supplied to a printing form of an offset printing press. The quantity of dampening solution is alternatingly varied about a preselectable mean value between a minimum value and a maximum value. The variation is independent of possible fluctuations due to deviations in the controlled supply of dampening solution. The mean, minimum and maximum values are defined from an ink distribution on a printed subject.

Abstract: A mounting apparatus for a printing cylinder in a printing press is provided. The apparatus includes a tapered bearing housing sleeve 12 adapted for axial insertion into, and retraction out of, a tapered bore 30 formed in a support frame 20 for the printing cylinder. The tapered bearing housing sleeve 12 has an outer circumferential surface 26 which is generally conically shaped forming only part of a cone and an inner core which has a cylindrically shaped bore 34 disposed therein. The tapered bearing housing sleeve 12 has an end with a flanged tip 32 for limiting the axial movement of the tapered housing sleeve within the tapered bore 30. The mounting apparatus further includes a generally annular-shaped bearing 14 which is disposed within the cylindrically shaped bore 34 of the tapered bearing housing sleeve 12. The generally annular-shaped bearing 14 is defined by an inner ring 38 and an outer ring 40 and a plurality of anti-friction elements 42 disposed between the inner ring and the outer ring.

Abstract: A method for regulating ink distribution in a printing machine is disclosed. In accordance with the disclosed method, a basic ink quantity and a compensating ink film thickness are determined for a printing plate to be loaded into the printing machine. All of the inking rollers of the printing machine are fed ink until the ink thickness on each roller is substantially equal to the compensating ink thickness. A steady state ink distribution within the printing machine will be attained relatively quickly, thereby minimizing print waste and time required to attain steady state.

Abstract: The invention relates to an apparatus for the metering of liquid media, especially varnish, of differing viscosity in an offset printing machine. Exchangeable metering subassemblies are assigned to a form cylinder. The first metering subassembly provided for processing low-viscosity media consists of a reservoir, a dipping roller, a metering roller and the form cylinder. The second metering subassembly for processing higher-viscosity media consists of a chamber doctor, a screened applicator roller and the form cylinder. In a further version, both metering subassemblies are assigned permanently to the form cylinder. Depending on the media to be processed, the necessary subassemblies are engaged with the form cylinder and the other subassembly is disengaged from the form cylinder.

Abstract: Method of performing operating steps in an adjustment of a printing press, wherein adjusting members preloaded in one direction of motion are displaceable, in chronologically at least partly successive or sequential operating steps, in a direction opposite to the one direction by adjusting cylinders upon which a pressure medium is actionable includes acting, via a first pressure medium system having a pressure limitation controllable in stages, upon a second pressure medium system to which a plurality of adjusting cylinders, at least some of which are preloaded with different forces, are connected; and device for practicing the method.

Abstract: When operating parts, such as a plate cylinder (3), a chamber doctor blade (4), an inking cylinder (5) and an ink trough (6), are to be inserted in a printing machine (13), said operating parts (3,4,5,6) are temporarily secured to a frame (2) adapted to move on a carriage (1) transversely to the latter's direction of motion. Then, the carriage (1) is placed in position in front of the printing machine (13), the front panel of which has previously been removed. After this, the frame (2) is run partially into the printing machine (13), causing the operating parts (3,4,5,6) to be released from the frame (2), after which a device in the printing machine (13) transfers them to their final positions, in which they are held securely in the printing machine (13). When said operating parts (3,4,5,6) are to be removed from the printing machine (13), the procedure is carried out in the reverse sequence.

Abstract: A method for eliminating gear train backlash in the drive of a sheet-fed printing machines when changing the printing mode of the machine between face printing and perfecting or vice versa is disclosed. The printing machine has a gear train, a longitudinal drive shaft, and a plurality of input drives connecting the drive shaft to the gear train. At least one separation device is provided in the gear train, and at least one clutch is provided in the drive shaft. Releasing both the clutch and the separation device disconnects the printing machine into decoupled regions. After the relative position of those regions are adjusted for the new printing format, the new relative position is fixed by engaging the separation device. The segments of the longitudinal drive shaft is then adjusted to apply a torque to the gear train to eliminate backlash in the drive. The positioning can optionally be performed by the main drive motor or a separate positioning drive connected to the drive shaft.

Abstract: Method of controlling a rotary printing machine having a thermal dryer to which a combustion system is post-connected, includes determining changes in temperature of exhaust gas in the combustion system and, in accordance therewith, varying the speed of operation of the rotary printing machine; and device for performing the method.

Abstract: So as to prevent ink leakage and reduce the amount of ink consumed, the device for supplying ink in a thin-film fashion to a printing plate includes rotation-stop members provided on an ink supply so that the rotation-stop members prevent any upward movement that would occur at an end portion of the ink supply with which a horizontally movable printing plate is in contact.

Abstract: An ink pump control system for an ink pump installed on printing presses, driven by a stepping motor, with the ink feed thereof being controlled in accordance with the revolution of the stepping motor, including a first pulse output device for outputting a pulse signal proportional to the operating speed of the rotary press, a memory device for storing ON/OFF bit strings in accordance with a printing element ratio of a plate surface area to which ink is to be fed obtained in advance by a printing element ratio measuring device, a second pulse output device for sequentially reading each bit in the ON/OFF bit string stored in the memory device every time a pulse signal outputted by the first pulse output device is inputted, and outputting a pulse signal in accordance with the read bits, and a motor driver for operating the stepping motor in accordance with the pulse signal outputted by the second pulse output device, so that ink feed is controlled optimally.

Abstract: An automated printing press (10) is provided with a plurality of printing stations (13), each having a printing mechanism (60) which prints at least one component image at spaced apart locations along a web (11). Each printing mechanism (60) is positionable to one side of the press for servicing. The print roller (61) is driven through a swingable gear assembly (268) that maintains gear spacing as the print roller to impression roller spacing varies and that engages and disengages tangentially to improve meshing. Microprocessor based computer controllers (400, 405) at each station (13) precisely and repeatably control positions of the printing mechanism (60) and precisely register the component images being printed at the stations (13).

Abstract: A process for affecting the ink value or colorimetric density of a printing ink layer on a substrate compares a production value in a microprocessor with a set value previously supplied to the microprocessor. Deviations of the production ink values or colorimetric values from the set values which exceed a pre-selected threshold will generate a signal that will change the rotational speed of a moistening device to reduce the difference between the production value and the set value.

Abstract: An undershot inking unit and associated method are disclosed. The undershot inking unit includes an ink fountain roller that is controlled independently of the printing speed of the printing machine, and in which the rotational contact angle of the distributor roller on the ink fountain roller is varied according to the printing unit speed. The method comprises controlling the rotational speed of the ink fountain roller independently of the printing speed of the printing machine; and varying the rotational contact angle of the intermittent ductor roller on the ink fountain roller according to the printing speed of the printing machine. In a preferred embodiment, the apparatus includes two coaxial cams rotatably adjustable with respect to each other. Each cam includes a predominant circumferential contour and a subordinate circumferential contour.

Abstract: A rotary intaglio printing machine has at least two printing mechanisms and a drying device arranged between the printing mechanisms, through which a web of paper to be printed upon successively passes. The printing mechanisms are so arranged that the web of paper is guided only by the plate cylinders and the impression cylinders of the printing mechanisms in a straight line from the preceding printing mechanism through the drying device in a contact-free mode to the following printing mechanism. The drying apparatus includes a housing through which the web of paper passes, as well as a fan arrangement and nozzle pipes which extend transversely to the direction of movement of the web of paper substantially over the entire width thereof and by which air, that is sucked out of the housing by the fan arrangement, is blown onto the web of paper.

Abstract: A printing press has a plate cylinder, an inking system and a dampening system. A bridge roller provides a path between the inking and dampening systems. The bridge roller is in contact with a dampening form roller, which in turn is in contact with the plate cylinder. The dampening form roller is driven by an arrangement that allows the dampening form roller to rotate at a differential speed with respect to the plate cylinder in order to clean hickies off of the plate cylinder. The speed of the bridge roller is controlled so as to provide a slip nip between the bridge roller and the dampening form roller and so as to control the ink-water balance, even when the dampening form roller is rotating at a differential speed.

Abstract: A flexographic printing system using mechanical and friction drive at the same time. The print cylinder is rotated by a friction drive only while printing (during the print cycle). The print cylinder is rotated past the anilox roll (during the inking cycle), and the print cylinder is reset to the start position ready for the next printing cycle by a mechanical drive. The print cylinder is preferably less than 360 degrees around, and most preferably measures only 170 degrees around. The print cylinder is made from plastic. Printing plates are pre-mounted permanently to a mylar carrier sheet that is designed with pin and hook holes that line up with pins and hooks that are part of the print cylinder. These plates have drive bearers as part of the mylar carrier sheet. The ink management system circulates the ink, cleans the entire ink system, and separates the ink from the waste and the cleaner. It also measures the pH of the ink or the viscosity level of the ink and automatically adds pH adjuster or thinner.

Abstract: A rotary stencil printing machine includes: stencil making section for processing the stencil sheet to obtain a printing stencil; a printing drum having an outer cylindrical surface and a clamping member which clamps the front end portion of the stencil sheet thus processed by the stencil making section, the printing drum being turned with the front end portion of the stencil sheet clamped with the clamping member to wind the stencil sheet on the outer cylindrical surface thereof; a conveyer for conveying the stencil sheet, which has been processed by the stencil making section, towards the drum; a movable guide which is movable between a standby position and a holding position which are spaced away from each other in a direction perpendicular to the surface of the stencil sheet located between the stencil making section and the drum, the guide moving from the standby position to the holding position, for lengthening a stencil conveying path between the stencil forming section and the clamping member, wherein

Abstract: The printing unit has two cooperating cylinders (1, 4) which form the printing nip and which have printing saddles (2, 5) separated by cylinder pits (3, 6). The paper web (7) passing through the printing nip is transported in the pilgrim-step mode, in order to print formats adjoining one another. The two cylinders (1, 4) are angularly adjustable relative to one another, in respect of the position of their printing saddles (2, 5) cooperating in the printing nip, in a manner offset by the amount of a circumferential distance which is approximately equal to the difference between the circumferential length (S) of a printing saddle and the circumferential length (B) of a printing image. The impression zone is therefore only approximately as large as the printing image, and the impression-free zone available for retracting the paper web is correspondingly enlarged.

Abstract: The invention provides a roller assembly including a roller for a damping unit or an inking unit in a rotary printing machine, which is supported relative to rollers via a pressure mechanism with springs, for example, a pressure spring and a leaf spring, so that the weight of the roller is balanced by the leaf spring. In this way, the roller has the same nip widths as the adjacent rollers. In addition, the roller is equipped with a holding mechanism, through which a bedding of the roller that has been set can be clamped, so that the roller has a fixed position during the printing process. The holding mechanism includes, for example, a pneumatic cylinder, a gripping lever or an adjusting screw.