Device for correcting the register of sheet overprints in a sheet-fed rotary printing machine

Abstract

Device for correcting the register of a sheet-overprint and for compensating for a distorted sheet in a sheet-fed rotary printing machine by deforming the leading edge of the sheet on a travel path thereof before the leading edge enters a printing unit, including an adjustable bending device for bending, in rhythm with a printing cycle of the machine, a support beam extending transversely to the travel path of the sheet and carrying a plurality of mutually adjacent sheet grippers, includes a pregripper device for executing swinging movements about a stationary axis and an axis adjustable into a given position, respectively, the pregripper device including a gripper fly forming the support beam for the sheet grippers, and respective rigid levers supporting the gripper fly at least at both ends thereof on a gripper-fly shaft, the bending device being cooperatively engageable with the pergripper device and being formed of a single adjustable deforming stop disposed substantially midway between the respective ends of the gripper fly and fixed to a frame of the machine, the bending device and theh pregripper device, except for the sheet gripper thereof, being located below the sheet travel path, the gripper fly, at a substantially midwise location thereof between the levers, being deformably engageable with the single adjustable deforming stop before the ends of the gripper fly, during a return swing thereof, have reached a zero setting in which the sheet grippers take over a sheet.

Dependencies are inferred from the claim text.