INK STICK

PROBLEM TO BE SOLVED: To provide an ink stick which has no adverse effect on reading of an encoding sensor composition part of the ink stick even when a speed and timing at which the ink stick traverses a sensor region of a supply path. SOLUTION: The ink stick 100 has a bottom surface 138, an upper surface 134, lateral side surfaces 140 and 144, and end surfaces 148 and 150, and also has an encoding sensor composition part 104 arranged on the bottom surface 138. The encoding sensor composition part 104 includes a plurality of sensor actuators 108, 110, 114, and 118 aligned generally linearly or in the shape of a track, and a transition indicating region 134 consists of a gap or a recess formed in the encoding sensor composition part 104 between the leading sensor actuator position and the trailing sensor actuator position of each track. The ink stick 100 may include one or more insertion key composition parts 154. COPYRIGHT: (C)2009,JPO&INPIT