Patent ID: 8246261
Filing Date: 2012-08-21
Classification: B41J

Abstract:
1. A printer configured to use a thermal head to sublime ink on an ink ribbon to form an image on a printing medium, the printer comprising: a cylindrical ribbon core around which the ink ribbon is wound; a rotating shaft configured to rotate the ribbon core; a first magnet and a second magnet configured to generate magnetic force lines in a space surrounded by an inner peripheral face of the ribbon core, and a magnet sensor located in the space surrounded by the inner peripheral face of the ribbon core and configured to detect the magnetic force lines generated by the first and second magnets only when the magnetic force lines are set in prescribed directions by rotation of the ribbon core, wherein the ribbon core comprises a cylindrical outer core with an outside peripheral surface around which the ink ribbon is wound and a cylindrical inner core with an outside peripheral surface to which the first and second magnets are fixed, and the inner core with the first and second magnets fixed thereto is installed inside the outer core.