Abstract: A roller cleaning device for a varnishing system in a printing press has liquid-supplying means pivotally arranged above the rollers conveying varnish. The spatial distribution of the liquid-supplying means differs over the length of the rollers. The liquid-supplying means are closer together in two edge zones than in the central zone; the liquid-supplying means in the central zone have nozzles that are spaced apart from one another at a relatively large interval. The liquid-supplying means come into operation at stopping and at the onset and cessation of printing. The liquid-supplying means in the edge zone operate, in accordance with format width, throughout printing.

Abstract: An arrangement for the transfer and conveyance of sheets between first and second printing units of a multi-color lithographic press which includes a receiving drum in the first printing unit, a feed drum in the second printing unit, impression cylinders associated with the drums, an endless chain, which includes links joined by pins, trained about the drums, and a guide rail following the path of the chain. A plurality of gripper carriages moveable on the rail are each coupled to the chain for movement therewith by a carriage coupler, each coupler including a drive roller on the chain mounted outboard parallel to the pins thereof. Each gripper carriage includes a yoke for snugly embracing the drive roller on the chain. The feed drum includes a radially mounted drive fork for engaging the cam roller of each gripper carriage as it comes into the vicinity of the feed drum in order to achieve a condition of accurate register between the feed drum and the gripper carriage.

Abstract: A varnishing unit for applying varnish in a strip of selected width on a sheet carried on the impression cylinder of a printing press distinguished by use of a plurality of adjustable varnish blocking rollers arranged adjacent a fountain roller between a varnish trough and a metering nip formed between a metering roller and the fountain roller. The blocking rollers are hard surfaced and of relatively small diameter, and are secured to the frame by arms located at the respective ends of each roller. Each blocking roller is individually adjustable between (a) a position in which it forcibly indents the surface of the fountain roller so as to substantially cut off the flow of varnish to the metering nip, in the region of width controlled by the blocking roller and (b) a position withdrawn from the surface of the fountain roller to permit passage of a strip of varnish in the controlled region to the metering nip and thence via intermediate rollers to the varnishing cylinder.

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.

Abstract: A lithographic sheet-fed press having an impression cylinder with a gap formed in the surface thereof and having a cooperating blanket cylinder having bearers at its ends. A pair of auxiliary short bearer members bridge the gap in the impression cylinder, presenting arcuate edges for engagement with the bearers on the blanket cylinder, the bearer members are arranged at such radial height that when the blanket cylinder rolls into the region of the gap the force of printing pressure between the cylinders is taken over by the auxiliary bearer members to maintain the transaxial pressure between the cylinders substantially constant throughout the revolution thereby avoiding the cyclical impact accompanying sudden build-up of printing pressure at the end of the gap.

Abstract: A gap cover of arcuate cross section for covering the longitudinal channel in the cylinder of a printing press, the cover being dimensioned to bridge the gap and held in place by first and second fastening assemblies accommodated below the presented surface. The first fastening assembly includes an axially oriented hook and stirrup, while the second assembly includes a radially oriented shaft having a flat head of oblong profile forming a pair of wings. The cover has a recessed portion radially aligned with the latching element and containing an aperture of mating oblong profile bounded by land surfaces so that the head of the latching element may project therethrough, for locking engagement with the lands upon rotation through 90.degree. by a turning tool. The shaft of the latching element has an associated detent for snapping the head from its free position to its locking position and for securely holding it there until intentionally released by additional turning movement.

Abstract: A device for use in a sheet delivery mechanism for a printing press for forcibly seating a sheet on a delivery pile notwithstanding the cushion of air below the sheet. The device includes a pair of tube assemblies arranged parallel to one another above the delivery pile symmetrically on opposite sides of the delivery center line, with each tube assembly consisting of inner and outer tubes in snugly telescoped relation, air being supplied to the inner tubes under pressure. The tubes within each assembly have registrable arcuately extensive ports.

Abstract: A device for continuously cleaning a bearer in a printing press which includes a carrier in the form of a plate pivoted on the frame for the movement toward and away from the bearer. Mounted on the end portion of the carrier, and oriented in a generally axial direction, is a first scraper in the form of a doctor blade of stiff but wearable material and a second scraper in the form of a relatively soft, lubricated bar of felt, the carrier being biased for simultaneous contact of the scrapers against the bearer surface. The first scraper is oriented at a slight angle with respect to the bearer axis so that the material which is scraped from the bearer tends to be urged sideways for continuous discharge. The second scraper occupies a pocket in the carrier so that it may be rotationally indexed into a new position in the pocket as its presented edge becomes worn.