Printing mechanism

A printing mechanism including a mandrel, and a tubular sleeve to be mounted on the mandrel, having an outer peripheral surface to which printing plates are attached;

• wherein the mandrel comprises a main body and sleeve support members arranged on an outer periphery of the main body,
• a plurality of the sleeve-support members being arranged on the main body at intervals in the axial direction;
• and wherein each respective sleeve-support member has a plurality of arm portions extending radially so as to support the sleeve from an inside thereof, and respective moving mechanisms for moving tip vicinities of the arm portions inward and outward in the radial direction;
• and wherein each respective sleeve-support member further has an interlock mechanism for synchronously driving each moving mechanism of the sleeve support members, the tip vicinities of the arm portions being engaged with the inner surface of the sleeve or released from the engaged inner surface of the sleeve by the synchronous motion of the tip vicinities of all arm portions inward and outward with the interlock mechanism.