Abstract: An arrangement for securing pure skew adjustment of a cylinder, for example, a plate cylinder in a sheet-fed rotary printing press relative to an adjacent blanket cylinder. A bearing assembly at one end of the plate cylinder includes a cylinder bearing telescoped over the shaft and having flat support surfaces thereon facing radially outward in opposite directions. A guide bearing having a cylindrical outer surface is formed with a central window for receiving the cylinder bearing. The window defines a pair of flat inwardly facing way surfaces spaced parallel to one another for snug reception of the flat support surfaces on the cylinder bearing. The window also defines side walls spaced sufficiently to permit freedom of adjustment of the cylinder bearing along the way surfaces. An eccentric sleeve is fitted between the guide bearing and the frame with means for rockably adjusting the same to move the plate cylinder toward and away from the blanket cylinder thereby to vary the impression.

Abstract: An inking system for a lithographic printing press in which the plate has a non-ink accepting column position. Ink from an ink fountain is conveyed to the plate over its full width by a series of roller elements including an ink drum and ending with a form roller which is in rolling engagement with the plate. Water from a water fountain is conveyed to the plate by a series of rollers ending with a water form roller. A sub-frame is positioned at the non-ink accepting column position. The sub-frame mounts a pair of guide rollers supporting a relatively narrow endless belt in an elongated loop, the belt presenting a flat ink-accepting surface. A relatively narrow roller segment couples one end of the loop to the plate while the other end of the loop is coupled to the ink drum so that the belt forms an ink "bridge" on the downstream side of the series of ink rollers.

Abstract: An apparatus for printing the back, or "verso", side of a sheet being fed from a sheet-fed printing press into a delivery unit, the sheets being conveyed by an endless loop conveyor made up of a pair of laterally spaced conveyor chains. Cross members extend between the chains at regular intervals and carry grippers for gripping the leading edge of a sheet. The chains are guided so that they form a delivery run and a return run spaced apart and generally parallel to one another. An impression cylinder is journalled between the runs having an axial length which is shorter than the lateral spacing between the chains. A blanket cylinder is journalled outside of the delivery run in rolling engagement with the impression cylinder. A plate cylinder having inking and dampening systems is in rolling engagement with the blanket cylinder. The impression and blanket cylinders have mating longitudinal grooves of a size sufficient to provide free passage for the cross members and grippers.

Abstract: An apparatus for varnishing a sheet being fed from a sheet fed printing press into a delivery unit, the sheet being conveyed by an endless loop conveyor made up of a pair of laterally spaced conveyor chains. Cross members extend between the chains at regular intervals carrying grippers for the leading edge of successive sheets. The chains are guided to form a delivery run and a return run spaced apart and generally parallel to one another. An applicator cylinder is journalled between the runs having an axial length which is shorter than the lateral spacing between the chains. A plate cylinder journalled in the frame outside of the return run is in rolling engagement with the applicator cylinder for supplying a varnish film thereto. A backing cylinder journalled in the frame outside of the delivery run is in rolling engagement with the applicator cylinder. The circumference of the cylinders equals the spacing between successive cross members and grippers.

Abstract: A device for seating and spreading a conveyed sheet evenly on an impression cylinder of a printing press thereby to prevent fluttering which includes a pair of pipes arranged parallel to one another in axially extending position above the cylinder. The pipes are bridged by a top wall and end walls to enclose the space between them to form a plenum chamber adjacent the surface of the cylinder, the under surfaces of the pipes defining, with the surface of the cylinder, an air gap of constant width.

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: An ink fountain for a printing press having a sub-frame which is mounted on the main frame of the press and which cooperates with a stationary fountain roller. A fountain blade is secured to the sub-frame with provision, interposed between the sub-frame and the blade, for establishing the thickness of ink film fed by the balde when the sub-frame occupies a reference position. The sub-frame has a hinge connection with the main frame for rocking movement about an axis remote from the tip of the blade between the reference position and a downwardly angled position in which an enlarged clearance gap is created at the tip of the blade, with the resulting rush of ink therethrough clearing the tip of the blade of contamination by accumulated particles of dirt or other impurities.

Abstract: An ink fountain formed of a trough and fountain roller, the trough having a recess along its presented edge which defines a ledge surface. A metering bar of durable resilient plastic, and which is of "L" cross section, has a first leg which occupies the recess and a second leg which overlaps, and is sealed to, the bottom of the trough, with the corner of the metering bar defining a gap. Adjusting keys are spaced along the metering bar, each key having a rotatable stem carrying an eccentric at its tip. The first leg of the metering bar has a groove of constant width extending along its inner surface, parallel to the fountain roller, in which all of the eccentrics are snugly received for localized adjustment of the gap, positively in both directions. A resilient sealing strip interposed between the ledge surface and the metering bar seals the second leg of the metering bar with respect to the frame.

Abstract: A vibration-free cylinder for a printing press in phased rolling engagement with a companion cylinder and which is formed of a cylinder body of star-shaped cross section having a central axial portion and four axial webs extending radially outward therefrom to define between them recesses of sector-shaped cross section. The surface of the cylinder is formed by first and second arcuate shell segments, the first of which extends over substantially half of a revolution and the second over substantially one-quarter revolution, the segments having parallel edges bridging the tip portions of the webs for enclosing all but one of the recesses which is uncovered to produce a gap defining the leading edge of the cylinder surface. The web at the leading edge is extended outwardly to the locus of the cylinder surface so that the cylinder body absorbs the impact with the companion cylinder which occurs at the leading edge at each revolution.

Abstract: An ink fountain construction for a printing press having a trough extending adjacent and parallel to the fountain roller to define a control space occupied by a flow control strip. The control strip is made up of a series of separate and independent flow control segments in the form of identical blocks of rectangular shape arranged snugly side-by-side for zonal control of the ink film fed to the roller. Each segment is rigidly secured to the frame at its lower end. Each segment has a relatively thin central section and is sprung forwardly to bias the presented upper edge of the segment against the fountain roller. A set of pull rods connected to the upper ends of the segments have adjusting means at the rear end to draw the connected segment rearwardly to define a gap with the fountain roller to establish the rate of ink feed in the respective zonal position.

Abstract: A bearing assembly for a cylinder in a printing press including an anti-friction bushing interposed between the spindle of the cylinder and a bore in the press frame. In contact with the outside surface of the bushing is a cylindrical layer of durable anti-friction plastic material formed of a flat ribbon which is of uniform thickness dimensioned to fit snugly to prevent any radial play between the bushing and the frame. In the preferred form of the invention two bushings are used, one inside the other, with the layer of plastic material interposed between them. At least one of the bushings may have inner and outer cylindrical surfaces which are eccentric with respect to one another and may be provided with means for rocking adjustment to provide limited throw of the spindle. The preferred form of plastic material is polytetrafluoroethylene, commonly known as Teflon.

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.

Abstract: A lithographic printing press having the usual plate cylinder, blanket cylinder and impression cylinder in pressure engagement with one another, the bearings having at least a normal amount of play so that the journals are supported in normal elevated positions in the bearings depending upon the direction of the pressure vectors, at least the blanket and impression cylinders having phased gaps in the surfaces thereof, tending to cause cyclical, momentary loss of support accompanied by dropping of the blanket cylinder from the normal journal position in the bearing as the region of the gap is traversed, followed immediately by lifting of the blanket cylinder back to normal position resulting in cyclical impact.

Abstract: A device for removing curling tendency in sheets, particularly sheets fed to printing presses, in which the sheets are conveyed over two beam-like supporting members arranged transversely with respect to the direction of sheet movement and presenting supporting surfaces which are spaced parallel to one another on one side of the sheet to define a groove in between them. Suction is applied within the groove to draw a passing sheet downwardly into the groove to produce a relatively sharp concave bend in the sheet thereby to counteract the curling tendency. The cross-sectional profile of the groove is variable by a movable member to vary the profile of the groove and hence the degree of sharpness of the bend, thereby permitting the degree of correction to be varied while keeping the suction substantially constant. The device, in both preferred and alternate embodiments, has provision for removing curling tendency in opposite directions.

Abstract: A feed drum assembly for feeding sheets in succession to the impression cylinder of a lithographic printing press which includes a cylindrical mantle having an axially and circumferentially distributed array of spacers which are spaced radially outward from the surface of the mantle at a constant spacing to define a support for the sheet as it makes a partial turn about the drum. An axially extensive nozzle directs air at high velocity in a direction chordwise of the drum and into the region between the sheet and the mantle. The change in direction of the air as it strikes and tends to follow the curved surface of the mantle creates an inward suction upon the sheet to draw the sheet against the spacers and thereby prevent fluttering as the sheet is transported at high speed. In the preferred embodiment of the invention the spacers are in the form of small, individually rotatable rollers smoothly surfaces with ink repellent synthetic material.

Abstract: A drive connection between a sleeve on the printing cylinder of a printing press and a hub on the associated driving gear, the hub being freely telescoped over the surface of the sleeve and the sleeve and hub having radially opposed grooves occupied by a key in the form of an entrainer. The entrainer includes two complimentary wedge portions which are mated along a substantially radially extending plane which is arranged at a shallow angle to the cylinder axis. The entrainer presents parallel lateral surfaces which register with the groove in the hub while only one of the wedge portions registers with the groove in the sleeve.

Abstract: A device for interrupting the feeding of sheets to a sheet-fed printing press. A feed table is provided having stops to define the registered position of successively fed sheets. After a register interval during which the sheet settles against the stops the sheet is picked up by a gripper cylinder. Photocells are provided for detecting failure of a sheet to register during the register interval. The photocells energize a retaining device on the feed table having a retaining foot which presses downwardly against the non-registered sheet to prevent such sheet from being picked up by the gripper cylinder. A device providing a time delay is interposed ahead of the retaining device to delay operation of the retaining device for a brief time interval to insure that the preceding sheet picked up by the gripper cylinder is clear of the feed table. A latch is provided to maintain the foot in pressing engagement with the sheet, but the foot is resiliently mounted so that an offending sheet may be manually removed.

Abstract: A conveyor for a printing press of the type employing a pair of spaced-apart roller chains guided for movement about an endless path having straight and curved portions. Carried by the chains in spaced positions are gripper frames each including first and second parallel crossbars carrying grippers and pads respectively, with mounting members at the ends of the crossbars. Adjacent pedestals are provided at the inner surfaces of each of the chains with each of the pedestals being secured to adjacent pairs of the pins in the chains. Each pedestal carries an inwardly facing mounting pin. Registering outwardly facing openings are provided in each of the mounting members for receiving the pins on the adjacent pedestals. One of such openings is snugly fitted to its pin to provide limited rocking movement of the mounting member.