Patent ID: 8320800

Claim:
A toner cartridge, comprising: a housing including an accumulating chamber for accumulating toner and a circulating chamber for circulating the toner through an outside of the housing, the circulating chamber including a surface having first and second ends in a longitudinal direction of the surface, the surface including a feed port located adjacent to the first end of the surface and a return port located adjacent to the second end of the surface, the feed and return ports being communicable with the outside of the housing; a first agitator disposed in the accumulating chamber and configured to convey the toner from the accumulating chamber to the circulating chamber through an opening; and a second agitator disposed in the circulating chamber and configured to agitate the toner, wherein the housing has a cross section perpendicular to the longitudinal direction of the surface, the cross section having a first length in a first direction directed to the surface and a second length in a direction perpendicular to the first direction and perpendicular to the longitudinal direction of the surface, the first length being greater than the second length, wherein the circulating chamber comprises a first cylindrical member and a second cylindrical member fitted around the first cylindrical member, the first cylindrical member being configured to rotate with respect to the second cylindrical member between a first position and a second position, wherein the first cylindrical member at the first position is configured to close the feed and return ports and interrupt a communication between the circulating chamber and the accumulating chamber through the opening, and wherein the first cylindrical member at the second position is configured to open the feed and return ports and establish the communication between the circulating chamber and the accumulating chamber through the opening.