PURPOSE: To improve interchange and durability of a type wheel, by a method wherein a setter shaft is attached or detached to an axial hole of the type wheel at the same position as the axial position of the pivotal shaft.

CONSTITUTION: When a movable table 18 is moved forward, accompanying with advancement of an engaging member 30, an intermediate lever is rotated clockwise by biasing of a spring 31, and corresponding to rearward motion of a bottom end 28a of the intermediate lever, a cassette holder 27 is rotated clockwise about a pivotal shaft 26 as a fulcrum by biasing of a spring 32. The pivotal shaft 26 to support the rotation of the cassette holder 27 is disposed on the same position as the axial center of a setter shaft 24 and an axial hole 35 of a type wheel 33 is disposed on the same position as the pivotal shaft 26, thereby position of the axial hole 35 by rotation of the cassette holder 27 is not shifted from the position of the inserted axial center of the setter shaft 24.