The invention relates to a printing unit containing at least one printing group (01; 31), which comprises at least two cylinders (03; 04) that form a printing nip (02). At least the two cylinders of the printing group are interconnected in a positive-fit by a drive. Said cylinders can be engaged with one another in a first position (ON), disengaged from one another in a second position (OFF) and disengaged from one another in a third position (STOP) at a great enough distance that a web (06) in the printing operation can be guided between the cylinders without making contact.