Abstract: A variable cutoff printing press includes a plate cylinder, a plate cylinder support removably supporting the plate cylinder, a blanket cylinder, a blanket cylinder support removably supporting the blanket, an impression cylinder and an impression cylinder support. An actuator for moving the blanket cylinder support accommodates different blanket cylinder sizes, the actuator further moving the impression cylinder support so that regardless of blanket cylinder size a gap exists between the blanket cylinder support and the impression cylinder support. An on impression actuator moves the impression cylinder support against the blanket cylinder support to set a desired print load. A method is also provided.

Abstract: The present invention provides a printing press. The printing press includes a frame, a plate cylinder, a plate cylinder support supporting the plate cylinder, a blanket cylinder for receiving an image from the plate cylinder, a blanket cylinder support supporting the blanket cylinder, an impression cylinder for supporting a printing substrate between the blanket cylinder and the impression cylinder, an actuator connected to and controlling a position of the plate cylinder support or the blanket cylinder support and a controller providing the actuator with a position setpoint, the actuator receiving position feedback signals to maintain the position setpoint during a printing operation. The present invention also provides a method for operating a printing press.

Abstract: An offset print unit includes a plate cylinder having an end, a rotatable plate cylinder support supporting the end and having a first bearing surface, a blanket cylinder having a blanket cylinder end, a rotatable blanket cylinder support supporting the end and having a second bearing surface and an actuating device for rotating the plate cylinder support and the blanket cylinder support, the first and second bearing surfaces contacting during a part of the rotation of the supports. A method is also provided.

Abstract: The invention relates to a sheet-guiding device in a printing machine. The object of the invention is to provide such a sheet-guiding device which in a printing/varnishing unit that is not involved in the printing/varnishing process, permits the smear-free passage of the printing material in a printing/varnishing nip. This is achieved in that on the blanket/plate cylinder 12, 2 there is arranged a printing plate with an ink/varnish-repellent surface coating, it being possible for the blanket/plate cylinder 12, 2 to be driven at the machine speed, and the sheet-carrying cylinder 1 conveying the printed or varnished printing material.

Abstract: A link mechanism is provided for setting and maintaining a minimum spacial distance between a blanket cylinder and a plate cylinder of a rotary printing press. The link mechanism includes a first link arm that is rotatably mounted on an axle of the blanket cylinder at one of the blanket cylinder. A second link arm rotatably is mounted on an axle of the plate cylinder. The first link arm and the second link arm are pivotably connected to each other for single axis pivoting about a point offset to one side of an imaginary line drawn through centers of the plate cylinder axle and the blanket cylinder axle. An adjustment mechanism is positioned between the first and second link arms on projections offset to the other side of the imaginary line so that the set minimum spacial distance between the plate cylinder axles and the blanket cylinder axle can be adjustably set and maintained throughout impression rotation of the rotary printing press.

Abstract: A retractable impression cylinder coater printer known as the “Lithoflex I™” combines lithographic and flexographic printing and coating in a single pass operation. The apparatus is adapted for installation on any printing station of a multi-color lithographic press, and is not limited to the last printing station. Ink or coating materials are applied from a printing plate or a blanket mounted on the plate cylinder of the retractable printer-coater unit and applied directly onto the surface of a substrate passing over the impression cylinder of the lithographic printing station just after being lithographically printed on that station. The combination printed substrate is passed to the next or a following lithographic printing station where it is lithographically overprinted.

Abstract: In an apparatus for the displacement of bearing blocks mounted on carriages which support shafts, a first carriage is carried for displacement in a carriage guideway fixed to the frame, and the other carriage is carried in a carriage guideway of the first carriage, these two carriage guideways being mutually parallel. To allow the carriages to be displaced with sufficient accuracy without expensive control devices, two spindle screw nuts designed as toothed belt pulleys are mounted in the first carriage parallel to each other and freely rotatable, and the screw spindles screwed into them are mounted selectively for free rotation and for being fixed, on the one hand in the machine frame and, on the other hand, in the second carriage. In the first carriage there is mounted a further drive belt pulley that is drivable by a motor and securable by a securing device, this further drive belt pulley driving an endless toothed belt that drives said spindle screw nuts designed as toothed belt pulleys.

Abstract: This invention relates to an apparatus for displacing shaft-mounting bearing stands, which are secured to carriages, in carriage guides, preferably for displacing the bearing stands of plate cylinders and inking rollers of a printing unit in carriage tracks of the inking unit supports of a multicolor rotary press, comprising screw drives, which are driven by electric motors. To solve the object to provide such an apparatus in which shafts and particularly plate cylinders and associated inking rollers can mutually independently be displaced relative to each other and, e.g., relative to an impression cylinder, the invention resides in that a screw that extends parallel to a single carriage track is rotatably mounted in the machine frame or on the inking unit support and is provided with a drive. A nut which is non-rotatably and axially immovably connected to a bearing stand or to a carriage is mounted on the screw.

Abstract: The present invention relates to an arrangement for eliminating the play or clearance between an eccentric bearing bush for a printing cylinder bearing and a bearing hole which rotatably accommodates the bush in the side frame of the printing press. Mutually contiguous surfaces of the bearing bush and the bearing hole are formed with contours which provide mutual contact between the surfaces along two areas which are substantially parallel to the bearing hole axis. The contact surfaces are separated by an angle of less than 180.degree. defined by gaps between an outer surface of the bush and an inner surface of the bearing hole.

Abstract: In a printing press including an intaglio cylinder, an impression cylinder and a blanket cylinder, for the purpose of throwing on and off these cylinders there is provided a control apparatus comprising a first detection switch which produces a selection signal when a rotating radial projection passes by, and a plurality of second detection switches which generate timing signals when passing by a plurality of radially spaced projections. The selection signal is used to select either one of the second selection switches, and the timing signal generated by a selected second detection switch is used to throw on and off the cylinders.According to this invention it is not necessary to use a number of expensive multistage preset counters which are liable to misoperate due to noise.

Abstract: A lithographic sheet fed press having means for clearing a jamming condition in which a plurality of sheets become wedged between the blanket and impression cylinders. The blanket cylinder is journaled in eccentric bushings having respective operating arms. Toggle linkages are respectively interposed between each arm and the associated frame plate and settable in a slightly overcenter operating condition for maintaining normal printing pressure between the blanket cylinder and the impression cylinder. A toggle-breaking power actuator is laterally coupled to the toggle linkages for breaking the same to the opposite side of dead center. A back-off power actuator is coupled to the bushings for imparting substantial rotation to the bushings accompanied by relief of pressure and full collapse of the toggle linkages with scissoring action. The actuators are energized in sequence to secure (a) release of the toggle linkages and (b) backing off of the blanket cylinder from the impression cylinder.