The rotation of the inner press roller 16 is synchronized with the rotation of the printing drum 10 by the gear train including a gear wheel 22 coaxial with the printing drum, a gear wheel 24 meshing with the gear wheel 22 and rotatably supported by an arm 26 swingable about the central axis of the printing drum, and a gear wheel 28 meshing with the gear wheel 24 and coaxially connected with the inner press roller 16 to rotate therewith and rotatably supported by an arm 18 swingable about a pivot axis Ob parallel with and distant from the central axis Oa of the printing drum. In the gear train, a brake 86 or 90 is provided for braking the gear wheel 28 or 24 to control the biasing out operation of the inner press roller 12 against the circumferential wall 12 of the printing drum. The braking action may be temporarily increased during a starting up of the printing operation. The distance between the axes of the gear wheels 24 and 28 may desirably be restricted not to increase beyond a predetermined distance.