Patent ID: 7290870

Claim:
An ink cartridge, comprising: an ink chamber configured to hold an ink therein, wherein the ink chamber comprises a wall having a first end and a second end opposite the first end; an ink supply portion positioned at the wall adjacent to the second end of the wall, wherein the ink supply portion has a particular opening formed therethrough; a translucent portion positioned at the wall between the first end of the wall and the ink supply portion, wherein the translucent portion is configured to be in fluid communication with the ink chamber, and the translucent portion has an inner space formed therein; a communication path having a first end coupled to the ink supply portion and a second end coupled to the ink chamber, wherein the communication path is configured to dispense ink from an interior of the ink chamber to an exterior of the ink chamber via the particular opening, and the communication path has a center line which is substantially perpendicular to the wall; and a movable member comprising: a signal blocking portion provided at a first end of the movable member, wherein the signal blocking portion is disposed within the inner space of the translucent portion; and a float provided at a second end of the movable member opposite the first end of the movable member, wherein the float is disposed within the ink chamber and has a specific gravity which is less than the specific gravity of the ink within the ink chamber, and the float 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, wherein when the float is in the first position the float does not intersect and does not pass through the center line of the communication path, and the float intersects and passes through the center line of the communication path at least when the float is in one of the second position and an intermediate position between the first position and the second position.