An ink cartridge includes a support member, and a rotatable member
connected to the support member. The rotatable member includes a pivot
portion formed at a point of connection between the support member and
the rotatable member, and a signal blocking portion. The signal blocking
portion is disposed within an inner space of a translucent portion. The
rotatable member also includes a float portion disposed within an ink
chamber. The float portion is positioned between the signal blocking
portion and the pivot portion, and the float portion is configured to
move between a first position and a second position based at least on an
amount of ink disposed within the ink chamber. Specifically, as the ink
within the ink chamber is dispensed from the interior of the ink chamber
to the exterior of the ink chamber a surface of the ink within the ink
chamber moves in a first predetermined direction, and when the float
portion moves from the first position to the second position each of the
float portion and the signal blocking portion moves about the pivot in a
second predetermined direction which is slanted with respect to the first
predetermined direction.