Printing unit having a distributor roller with a separate drive motor and printing press having the printing unit

A printing unit for a printing press, the printing unit comprising:

• a plurality of distributor rollers configured to carry out an axial movement;
• at least one separate drive motor each configured to exclusively drive said axial movement of a respective one of said distributor rollers;
• at least one rotary clutch and at least one recirculating ball screw, said at least one separate drive motor for said distributor rollers being at least one rotating electric motor transmitting power to said distributor rollers through said at least one rotary clutch and said at least one recirculating ball screw;
• a sensor detecting said axial movement of said distributor rollers driven by said at least one separate drive motor;
• and
• a control unit storing different selectable modes of operation of said distributor rollers, said modes of operation including a regular printing mode, an iris mode and an inking unit washing mode, said control unit being connected to a control device configured to adjust said at least one separate drive motor to drive said axial movement of said respective one of said distributor rollers independently of axial movements of others of said distributor rollers.