Device for engaging and disengaging the printing unit cylinders

摘要

The invention relates to a device for engaging and disengaging the printing unit cylinders in offset printing machines, in which the printing unit cylinders are mounted in eccentric bushes which are rotated for the purpose of engaging and disengaging the printing unit cylinders by means of hydraulic operating cylinders on both sides of the machine. The object of the invention, to reliably guarantee synchronisation of the engaging and disengaging movements of the impression cylinders on both sides of the machine, is achieved according to the invention in that the operating cylinders are arranged in a parallel connection via a pressure-medium device and lines. In this case, there are arranged in the pressure-medium device flow control valves and non-return valves which can be adjusted separately in the pressure line and in the outlet line, or flow control valves in the pressure line in conjunction with rectifiers, or flow dividing valves with non-return valves in the pressure line and in the outlet line, or mechanically rigidly coupled, pressure-medium-operated rotation motors in the cylinder inlet lines. <IMAGE>