Abstract: An ink ribbon cassette is pivotably mounted to a printer. Ink ribbon is accommodated in the ink ribbon cassette and is caused to travel by a ribbon feed roller driven by a drive shaft provided in the printer. Printing operation is carried out at the cassette end arm portion by a printing head, while the cassette end arm portion is reciprocatingly moved in the widthwise direction of the ink ribbon relative to the fixed printing head by an actuating mechanism so that a printing region of the ink ribbon is diffused and becomes wider than a printing width of the printing head. The actuating mechanism includes a small gear integral with the ribbon feed roller, a cam driven by the small gear, and a lever engaging with the cam.

Abstract: One of a ribbon feed roller (32) and a pressure roller (34) for making an endless ink ribbon (30) run is displaceable relative to the other roller thereof for facilitation of replacement of the ink ribbon, and can be locked at a withdrawn position thereof. In a state where one roller is locked at the withdrawn position, mounting of the ink ribbon cassette on a printer is obstructed. Also, a running direction and an orientation of the endless ink ribbon are defined so that damage to the bonded portion of the endless ink ribbon is delayed as much as possible.