Patent ID: 8195069

Claim:
A developing cartridge comprising: a casing configured of a first frame and a second frame with a space formed therebetween; and a developer-carrying member that is supported in the first frame and that is configured to carry developer; the first frame comprising a bottom wall and a pair of side walls erected from both sides of the bottom wall and having a box shape that is open on a side opposite the bottom wall; the second frame being mounted over the pair of side walls so as to cover the open side of the first frame and having a partition extending into the space formed in the casing; the partition contacting the bottom wall of the first frame and spanning between the pair of side walls of the first frame, thereby separating the space within the casing into a first chamber on a side near the developer-carrying member and a second chamber on a side far from the developer-carrying member, wherein only the first chamber is configured to accommodate developer.