Abstract: A rotatable plate cylinder (10) for supporting a printing plate (150) has an open passage (34) and a locking member (26) supported for movement in the passage (34). The locking member (26) is movable inward of the passage (34) to a closed position, and is movable outward of the passage (34) to an open position. The locking member (26) is subjected to a first centrifugal force which urges it to move outward from the closed position toward the open position when the plate cylinder (10) rotates. A balance member (28) is subjected to a second centrifugal force when the plate cylinder (10) rotates. Connecting pins (100) direct the second centrifugal force against the locking member (26) oppositely to the first centrifugal force.

Abstract: A method of cleaning a mechanism having ink-conducting rollable cylindrical members in a printing unit of a rotary printing press includes spraying solvent into a nip between the ink-conducting rollable cylindrical members, rotating the ink-conducting rollable cylindrical members so as to squeeze the solvent through the nip between the rollable cylindrical members and thereby apply pressure in the nip to an ink/dampening solution mixture on the rollable cylindrical members for loosening the mixture, and removing loosened ink and impurities from the printing unit; and apparatus for performing the method.

Abstract: A printing unit (10) includes a blanket cylinder (20), a bearing assembly (56) and a door assembly (72). The blanket cylinder (20) carries a tubular printing blanket (36). The bearing assembly (56) includes a bearing housing (58) fixed to the stub shaft (50) on the end of the blanket cylinder (20). The door assembly (72) includes a door (82) which is supported for pivotal movement on a frame wall (22) of the printing unit (10). The door (82) has a closed position in which it extends across an opening (76) in the frame wall (22), and an open position in which it does not extend across the opening (76) in the frame wall (22). A clamping assembly clamps the bearing housing (58) on the door (82) when the blanket cylinder (20) rotates during a printing operation. The clamping assembly includes a first clamp (100) which fixed to the door (82) and a second clamp (102) which is supported on the door (82) for movement relative to the first clamp (100).

Abstract: A rotary printing press comprises a frame including spaced sidewalls (12, 14), first and second printing cylinders (16, 18), and bearing members (26, 28) for supporting the ends (20, 22) of the first and second printing cylinders (16, 18) for rotation in the sidewalls (12, 14) of the frame. The first and second bearing members (26, 28) are removable from one end of the printing cylinders (16, 18). A first counterpoise assembly (40) includes a first rotary arm (50) having a supporting position for applying a force to the other end (20) of the first printing cylinder (16) to support the first printing cylinder (16) in the frame when the first bearing member (26) is removed. A second counterpoise assembly (42) includes a second rotary arm (50) having a supporting position for applying a force to the other end (22) of the second printing cylinder (18) to support the second printing cylinder (18) in the frame when the second bearing member (28) is removed.

Abstract: A method for aligning at least one machine unit (36) on a base (42) comprises the steps of installing alignment markers (28) on the parts (12, 14) of a machine unit (36) to be aligned, and correcting the locations of the alignment markers (28) to effect a correction in the locations of the parts (12, 14) on which they are installed. The alignment markers (28) are installed in positions which have precise relationships to the positions of function specific openings (20) in the parts (12, 14) which are preferably formed in metal cutting machining. A correction in the locations of the alignment markers (28) thus effects a correction in the locations of the function specific openings (20). The alignment markers (28) enable an alignment of parallel parts (12, 14) of a single machine unit (36) as well as alignment of several machine units (36, 38, 40) arranged one after the other in series.

Abstract: In a printing press, a ductor assembly for transferring ink from a slowly rotating fountain roll to a rapidly rotating ink receiving roll includes a carriage and first and second idler rolls supported in counterrotating engagement on the carriage. In one embodiment, the ductor assembly moves between a first position in which the first idler roll contacts and picks up ink from the fountain roll, and a second position in which the second idler roll contacts and transfers ink to the ink receiving roll. The ductor assembly is driven to rotate at a speed intermediate the speeds of the fountain roll and the ink receiving roll, in a direction the same as the direction of rotation of the second idler roll about its own axis, and opposite to the direction of rotation of the first idler roll about its axis.

Abstract: An offset printing apparatus rotates the plate cylinder steadily with a minimum of torsional interference caused by impact of the reciprocating ductor roll with the vibrator roll. The vibrator roll is driven to rotate independently of rotation of the other rolls which lead successively to the plate cylinder.

Abstract: A plate cylinder of an offset printing press is adjustable. A motor has an output shaft operatively connected with the plate cylinder to, when driven, adjust the position of the plate cylinder. A tachometer provides a speed reference signal indicative of the rotational speed of the plate cylinder. A register mark error sensor provides an adjustment control signal indicating that the plate cylinder should be adjusted. A computer responds to the speed reference signal and the adjustment control signal to control a DC drive. The DC drive drives the motor at a speed which varies with the rotational speed of the plate cylinder. The plate cylinder is thereby moved to a desired position at a rate which is a function of the operating speed of the printing press. The plate cylinder is moved to the desired position at a slow rate when the printing press is operating at a slow speed and at a fast rate when the printing press is operating at a fast speed.

Abstract: In a printing press, a ductor assembly for transferring ink from a slowly rotating fountain roll to a rapidly rotating ink receiving roll includes a carriage and first and second idler rolls supported in counterrotating engagement on the carriage. In one embodiment, the ductor assembly moves between a first position in which the first idler roll contacts and picks up ink from the fountain roll, and a second position in which the second idler roll contacts and transfers ink to the ink receiving roll. The ductor assembly is driven to rotate at a speed intermediate the speeds of the fountain roll and the ink receiving roll, in a direction the same as the direction of rotation of the second idler roll about its own axis, and opposite to the direction of rotation of the first idler roll about its axis.

Abstract: An anglebar and/or a compensator roller in a folder of a printing press is adjustable. A motor has an output shaft operatively connected with the anglebar and/or the compensator roller to, when driven, adjust the position of the anglebar and/or the compensator roller. A tachometer provides a speed reference signal indicative of the speed of movement of a web of sheet material relative to the anglebar and/or the compensator roller. A web position sensor provides an adjustment control signal indicating that the anglebar and/or the compensator roller should be adjusted. A computer responds to the speed reference signal and the adjustment control signal to control a DC drive. The DC drive drives the motor at a speed which varies with the speed of movement of the web of sheet material. The anglebar and/or the compensator roller is thereby moved to a desired position at a rate which is a function of the speed of movement of the web of sheet material relative to the anglebar and/or the compensator roller.

Abstract: An apparatus is disclosed for controlling fluid flow at a flow control location between first and second rollers. Each roller is rotatable about its longitudinal central axis. The two rollers are disposed adjacent to each other so as to form a flow control location or nip between the rollers. The nip has an entrance side and an exit side. As the rollers rotate, fluid from a fluid pan is carried on the outer surface of the first roller to the entrance side of the nip. Some of the fluid at the nip is transferred onto the outer surface of the second roller. As the rollers continue to rotate, the fluid flows out of the nip at the exit side of the nip. An excess fluid condition occurs at the nip when the amount of fluid flow to the entrance side of the nip exceeds the amount of fluid flow from the exit side of the nip. A brass collar is connected at one end of the first roller. Another brass collar is connected at the outer end of the first roller.

Abstract: A method and apparatus is disclosed for preventing leakage of a fluid such as a lubricant from a gear case. In this method and apparatus, the ambient pressure inside the gear case is maintained slightly lower than the air pressure outside the gear case. By maintaining this pressure differential, air flows from outside the gear case into the gear case through any openings from which lubricant would otherwise leak. Leakage of the lubricant through such openings in the gear case is thereby prevented.

Abstract: A method and apparatus are disclosed for registering a perfecting offset printing unit to a reference perfecting offset printing unit while minimizing displacement between associated non-print gap areas. The circumferential position of the upper printing plate and the lower printing plate of the unit to be registered is monitored with respect to their associated blankets. The print registration between the unit to be registered and the reference unit is monitored. Printing position changes for the upper printing couple and the lower printing couple of the unit to be registered that are needed to effect registration with the reference unit are determined. A circumferential bias is determined responsive to the determined printing position changes needed and responsive to the monitored circumferential position of the upper printing plate and the lower printing plate.

Abstract: A rotary printing press comprises a rotatable blanket cylinder and a plate cylinder disposed in rolling engagement with said blanket cylinder. A skew-adjusting means varies the angle between the blanket and plate cylinders. A form roll is disposed in rolling engagement with the plate cylinder. Plate cylinder throw off means moves the plate cylinder to disengage the plate cylinder from the blanket cylinder. The plate cylinder throw off means comprises means for disengagement of said plate cylinder from said blanket cylinder without skew movement of the plate cylinder. Form roll-plate cylinder adjustment means is provided for adjusting the center-to-center distance between the form roll and the plate cylinder. A cam has surface means for maintaining the center-to-center distance between the form roll and the plate cylinder as the plate cylinder is thrown off the blanket cylinder and as the skew adjusting means varies the angle between said blanket and plate cylinders.

Abstract: A printing press comprises a frame. A plate cylinder is mounted in the frame for rotation about a first axis and a blanket cylinder is mounted in the frame for rotation about a second axis. The plate cylinder and the blanket cylinder have a contact pressure therebetween for printing operation. A skew eccentric is supported by the frame and is associated with at least one end of the plate cylinder. The skew eccentric is operable to change the relative angular positions of said first and second axes. A means is connected with said skew eccentric for maintaining the contact pressure between the plate cylinder and the blanket cylinder substantially unchanged upon rotation of the skew eccentric.