Abstract: A device and a method for acting upon sheets in a sheet delivery system of a printing press, wherein sheets can be printed selectively on one side and on both sides thereof, includes a sheet tautener having a surface by which it is integrated into at least one adjacent sheet feeding plane, mounting supports for the sheet tautener, and adjacent air nozzles for forming an air cushion on the sheet tautener when the printing press is in a single-sided printing mode for printing on one side thereof and is in a first-form and perfecter printing mode for printing on both sides thereof.

Abstract: A stencil printer of the present invention is selectively operable in a simplex print mode or a duplex print mode and includes two drums. The drums each has a respective master support on its circumferential surface. The master supports of the two drums are movable into and out of contact with each other without the distance between the shafts of the drums being changed. In the duplex print mode, the master supports contact each other with the intermediary of a paper so as to print images on both sides of the paper at the same time. The printer obviates noise and insures high image quality.

Abstract: A continuous web of material is unwound from a roll by driven pull rolls that feed the web material to a printing unit in a feedline of an envelope making machine. The printing unit prints a selected one of the inside surface and the outside surface of the web before the web is cut and folded to form envelopes. The printing unit is supported by a base which is mounted for pivotal movement on a platform of a fixed frame member. The base is connected to the platform by a vertical pivot pin for movement through a 180.degree. between a first position for printing the inside surface of the web and a second position for printing the outside surface of the web. The base of the printer is locked to the platform in the selected one of the first and second positions to perform the desired printing operation. The web is fed between counter-rotating impression and plate cylinders rotatably mounted and driven on the printer base.

Abstract: Modular printing apparatus wherein multiple central-impression presses may be linked to one another, either directly or through a perfecting assembly that reverses the facewise orientation of cut sheets. The presses each contain circuitry defining a signal and control path for the press and a plurality of electrical contacts that renders the path accessible and facilitates serial connection of the presses without disruption of the path. At least one of the presses includes a port for receiving connection to a controller, which thereby engages the signal path and, via the path, operates the presses independently or together as appropriate. The system includes a connector that is used to couple the electrical contacts of one press to those of the second press, thereby establishing a single, continuous signal and control path through both presses accessible to the controller.

Abstract: Chain conveyor of a sheet-fed printing machine for first-form and perfector printing includes guided revolving gripper chains, having a respective lower strand and a respective upper strand, at least a part of the lower strand being disposed in a sheet-conveying region, a sheet-guiding device disposed in the sheet-conveying region below the lower strand for guiding in a sheet-conveying direction a sheet having a downwardly directed printed side, the sheet-guiding device being formed with a guide surface continuously movable in the sheet-conveying direction at a sheet-conveying velocity parallel to the lower strand of the gripper chains, and a device for continuously driving the guide surface.

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: Rotary printing press for two-sided printing of sheets having a first and a second printing unit, respectively including an impression cylinder, the press including a sheet feeder having a device for separating sheets singly from a feeder pile and a device for feeding the singly separated sheets to the first printing unit for printing one of the sides of the respective sheets and to the second printing unit for printing the other of the sides of the respective sheets, a delivery system having a device for conveying and depositing the sheets on at least one delivery pile and including a disconnectable delivery, a control device for controlling operational sequences performed in the rotary printing press, the first and second printing units being satellite printing units disposed as mirror images in tandem horizontally and, respectively, having a plurality of printing devices arranged around each of the respective impression cylinders thereof, the sheet feeder and the disconnectable delivery being assigned to t

Abstract: Method and apparatus for the varnishing and printing of sheets in a printing machine. A feed drum incorporates a counterpressure surface to form a first nip with an impression cylinder. As sheets are fed to the impression cylinder and transported through the first nip, a constant pressure at the first nip consistently transfers ink to a verso side of each sheet. Arranged thereafter, a varnishing cylinder supplied with a quantity of varnish contacts the impression cylinder creating a second nip. As the sheet passes through the second nip, the recto side of the sheet is coated with the varnish. The impression cylinder thus receives a constant pressure for transferring ink to the sheet independent of the pressure provided by the varnishing cylinder. Accordingly, even a partial or intermittent varnishing of the recto sheet side has no adverse effect on print quality, and the sheet does not have to be transferred from the impression cylinder to a separate varnishing unit.

Abstract: The invention relates to a sheet-fed rotary printing press for multi-color printing with an in-line arrangement of the printing units. Each printing unit comprises a plate cylinder, a blanket cylinder and an impression cylinder, all of a single diameter, as well as three sheet-transfer drums. The sheet-transfer drums of single diameter are provided for printing jobs using a one-sided multi-color printing process. On the other hand, the design for recto-and-verso printing is provided with a storage drum and a turning drum, with the storage drum being of double diameter. Depending on the job structure, the printing press according to the invention can later be converted at the printing shop from one design to the other.

Abstract: A sheet-fed rotary printing press for printing both the obverse and reverse side of a printing sheet. The printing press is provided with at least one obverse side printing unit including an impression cylinder and a discharge cylinder in contact therewith. The printing press is also provided with a reverse side printing unit in confrontation with the discharge cylinder. The discharge cylinder also functions as an impression cylinder for the reverse side printing.

Abstract: In accordance with the invention a varnishing unit in a printing machine is provided which simultaneously varnishes and perfects printing sheets. The varnishing unit comprises a rotating impression cylinder in contact with a rotating varnishing cylinder to create a nip between the two cylinders through which sheets are individually drawn. In order to perfect each sheet at the nip, the impression cylinder has at least one plate or a blanket secured to its surface. Depending on whether a plate or a blanket is secured to the impression cylinder, an appropriate dampening and inking means is provided. Similarly, the varnishing cylinder is supplied a controlled quantity of varnish by a varnishing means.

Abstract: A process and apparatus for perfecting printing on paper sheets, one side being printed by the offset method and the other side being printed by direct planography, is provided for a five-cylinder sheet-fed offset press having an impression cylinder, first and second plate cylinders and first and second blanket cylinders, the latter being disposed respectively between the plate cylinders and the impression cylinder, wherein one or more printing plates suitable for direct planography are clamped on the impression cylinder in accordance with the size relationship between the impression cylinder and the blanket cylinders, the first plate cylinder and first blanket cylinder are arranged so as not to transfer indicia although the blanket cylinder is engaged with the impression cylinder, the effective diameter (d) of the first blanket cylinder is made slightly less than the dimension that corresponds to an integral multiple (or reciprocal thereof) of the effective diameter (D) of the impression cylinder, and the pr

Abstract: To improve the versatility of offset printing machines by permitting, selectively, prime printing or prime-and-verso printing, a printing system of at least one plate cylinder (1) in engagement with a rubber blanket cylinder (7) is provided, the plate cylinder having the customary inker (3) and damper (5) associated therewith. Printing is effected against an impression or counter cylinder (9). The impression or counter cylinder is arranged for application of verso print image on the sheet by having an attachment arrangement (13-24) to attach a flexible planographic printing plate (12) on the surface thereof; a further inker (29) is provided, selectively engageable with the planographic printing plate, if verso printing is to be effected. If the printing plate is an offset printing plate, an additional damper may be provided, selectively engageable therewith.

Abstract: To permit, selectively, positioning of drums or cylinders in rotary sheet printing machines having, selectively, different functions, a cylinder layout is provided, generally in form of an inverted Y, which permits placing, selectively, blanket cylinders, transfer drums, chain system delivery drums and the like at predetermined locations so that, with six bearing positions (9-14) in a standard side wall (1), different printing modes and arrangements providing for single or multiple prime (P, P') and verso (V) printing can be effected, the printing positions being, for example, formed by bores for bearings of the respective cylinders which, if not used, can be plugged or left as space areas, preferably with marked centers, in the side walls; a standard side wall thus can be provided for multiple types of machines which also permit subsequent expansion of machine printing capability without exchange of side wall support or frame structure.

Abstract: Offset, rotary newspaper printing press systems, particularly a method of enhancing inking of the plate cylinder. The method includes defining a plurality of ink repository cells within the surface of an inking cylinder, immersing the repository cells within an ink reservoir, scraping excess ink from the surface of the inking cylinder and rotating the inking cylinder and ink-filled cells against the surfaces of a pair of form rollers, contacting the plate cylinder. Modifications of invention include rotating the watering cylinders against one of the form rollers of the pair or rotating the watering cylinder against a form cylinder which independently controls the plate cylinder.

Abstract: An image detecting and positioning device for an off-set printing machine capable of printing on both sides of a printing sheet. Electromagnetic clutches couple and disengage gears from the shafts of rubber cylinders in response to input signals with the two gears engaged with each other. Electromagnetic brakes are also coupled to the shafts of the rubber cylinders. Rotational angle detectors provide outputs related to the rotational positions of the shafts of one of the rubber cylinders and its plate cylinder. The electromagnetic brakes and clutches are operated in response to outputs from the rotational angle detectors to correctly position images on the rubber cylinders.

Abstract: The squeeze of two opposed paper-receiving rolls of an offset printing press may be infinitely adjusted within a relatively small range by virtue of the fact that each end plate supporting the rolls has a slit therein between the axes of rotation of the rolls which will permit slight deformation of the plate in a direction transversely of the slit upon manipulation of an adjusting mechanism to shift the rolls toward and away from each other. Adjustment mechanism is provided on each plate and includes a cam that, when rotated by the longitudinal displacement of an operating link, has the effect of opening or closing a corresponding slit to thereby effect minute adjustment of the spatial relationship of the roll axes. The operating link has a specially threaded section from which the longitudinal displacement of the link is derived, the arrangement being such that the ratio of link rotation to link displacement is relatively high so that very fine adjustment of the critical roll relationship can be achieved.

Abstract: A perfector printing press having a full size impression cylinder with a blanket thereon between the perfector roll and the plate roll so that printing is not done on the smaller radius perfector roller. The perfector is easier to reach for cleaning and changing and the quality of the printing is improved. The perfector may be spring loaded to prevent jam ups and pivoted about the impression cylinder for easier access.