Printing press with registration control

摘要

A printing press includes a plate cylinder defining a nip with an impression cylinder. A drive shaft is drivingly connected to the impression cylinder to rotate the impression cylinder. A first gear is mounted on the drive shaft and is drivingly connected to the drive shaft. A differential mechanism is driven by the first gear. A second gear is mounted on the drive shaft for rotation relative to the drive shaft. The second gear is rotatably driven by the differential. A third gear in mesh with the second gear drivingly connects with the plate cylinder to rotate the plate cylinder. A correction drive motor, when energized, varies the speed at which the differential drives the second gear. The correction drive motor thus varies the speed of rotation of the plate cylinder relative to the impression cylinder.