A conveyor for a sheet-fed rotary printing press for transferring sheets away from an impression cylinder includes a delivery cylinder disposed adjacent the impression cylinder, and a chain conveyor having a plurality of sheet grippers, adapted for moving the grippers about the delivery cylinder for successively engaging sheets on the impression cylinder. The delivery cylinder has a gap in its outer periphery for receiving successive of the sheet grippers during transfer of a sheet from the impression cylinder to the sheet grippers. The sheet grippers each include a support and a pivotable gripper finger, and a displacer mounted on and extending rearwardly of each gripper support for bridging the gap in the delivery cylinder within which the gripper is disposed during a sheet transfer operation, and for maintaining tension in the sheet during transfer from the impression cylinder to the chain conveyor. The displacer is comb shaped having a plurality of rearwardly extending arcute shaped teeth. A sheet support comb also may be supported on the delivery cylinder with its teeth forwardly extending in intermeshing relation with the teeth of the displacer so as to completely bridge the gap within which the sheet gripper is disposed. Antismear rollers or like elements may be disposed on the teeth of the displacer and the sheet support comb to facilitate smooth transfer of the sheet away from the compression cylinder.
Provided in a sheet-fed printing machine is a sheet transport drum, including a first comb segment and a second comb segment, the second comb segment being mounted so as to be rotatable relative to the first comb segment for providing an adjustment to a format length corresponding with that of a printing-material sheet, the comb segments being formed of prongs having interspaces therebetween, and at least one covering provided for covering the interspaces between the prongs.
A sheet transfer device for a sheet-fed rotary printing press includes a registration correction device. The registration correction device deforms the leading edge of the sheet using a deformable gripper bridge system. The gripper bridge system includes a gripper bridge which extends continuously over the width of the sheet transport path. The gripper bridge is supported at each of its two ends by a pivotable support to allow the gripper bridge to assume a deformed shape similar to that of a simply-supported beam.
Device for register correction and for compensating for distorted sheets in a pregripper of a feeder for a sheet-fed rotary printing press has a frame-fixed brace disposed on a pregripper shaft and located approximately centrally between end supports on a gripper bar, the gripper bar being supported rigid against torsion at opposite ends thereof on the pregripper shaft and being capable of executing swivelling movements in a sheet-feeding direction and in a direction opposite thereto, the frame-fixed brace serving for elastically bending the gripper bar in the sheet-feeding direction before the sheet is gripped by sheet grippers which are disposed side by side on the gripper bar and are swivellable about an axis of the pregripper shaft, the brace including a cam roller by which it runs onto an adjustable cam having a frame-fixed support, and an articulated joint with an eccentric element having a lever arm connected thereto for carrying the cam roller spaced from a center of the eccentric element.
