Patent ID: 8208839

Claim:
A developer cartridge comprising: a housing configured to accommodate developer; a rotation shaft that is rotatably supported by the housing and passes across an inside of the housing; a supply opening formed in a wall of the housing opposite in a diameter direction of the rotation shaft; a return opening formed in the wall of the housing at a position displaced from the supply opening in an axial direction of the rotation shaft; a first agitation blade that is supported by the rotation shaft and is configured to pass through a position opposite the return opening along an inner surface of the housing by rotation of the rotation shaft; and a second agitation blade that is supported by the rotation shaft and is configured to pass through a position opposite the supply opening along an inner surface of the housing by the rotation of the rotation shaft, wherein the first agitation blade is configured to allow the developer returned through the return opening to flow into the housing; and wherein a free end of the first agitation blade is bent to make sliding contact with an inner circumferential surface of the housing and is directed toward a forward side in a rotation direction thereof.