Developer cartridge

A developer cartridge, comprising:

• a housing extending in a first direction and configured to contain toner, the housing having a first end in the first direction, and a second end located away from the first end in the first direction;
• a developing roller rotatable about a roller axis extending in a second direction different from the first direction, the developing roller being located nearer the first end than the second end in the first direction, the developing roller having an uncovered surface located at a first end of the developing roller in a third direction and exposed outside the housing, and a covered surface located at a second end of the developing roller in the third direction and located inside the housing;
• a first boss extending in the second direction and movable together with the housing, the first boss being located at a first outer surface of the housing in the second direction, the first boss being located away from the developing roller in the first direction and the third direction;
• and
• a second boss extending in the second direction and movable together with the housing, the second boss being located at the first outer surface, the second boss being located farther away from the developing roller than the first boss in the first direction and the third direction,
• wherein the second boss is configured to receive a pressing force directed from the second end of the housing in the first direction toward the first end of the housing in the first direction, and
• wherein the developer cartridge is configured to rotate about the first boss in response to the second boss receiving the pressing force directed from the second end of the housing in the first direction toward the first end of the housing in the first direction.

A developer cartridge, comprising:

• a housing extending in a first direction and configured to contain toner, the housing having a first end in the first direction, and a second end located away from the first end in the first direction;
• a developing roller rotatable about a roller axis extending in a second direction different from the first direction, the developing roller being located nearer the first end than the second end in the first direction, the developing roller having an uncovered surface located at a first end of the developing roller in a third direction and exposed outside the housing, and a covered surface located at a second end of the developing roller in the third direction and located inside the housing;
• a first boss extending in the second direction and movable together with the housing, the first boss being located at a first outer surface of the housing in the second direction, the first boss configured to bear a weight of the developer cartridge when the first boss is supported by a support surface of a first side plate of a drum unit, the first boss being located away from the developing roller in the first direction and the third direction;
• a second boss extending in the second direction and movable together with the housing, the second boss being located at the first outer surface, the second boss being located farther away from the developing roller than the first boss in the first direction and the third direction, the second boss configured to receive a pressing force directed from the second end of the housing in the first direction toward the first end of the housing in the first direction;
• and
• a pressure receiving surface located farther away from the developing roller than the first boss in the third direction, the pressure receiving surface configured to receive a pressing force in the third direction from a pressing member of the first side plate of the drum unit,
• wherein the first boss is located away from the developing roller in the first direction by a first distance,
• wherein the pressure receiving surface is located away from the developing roller in the first direction by the first distance or by a second distance smaller than the first distance,
• wherein the second boss receives the pressing force directed from the second end of the housing in the first direction toward the first end of the housing in the first direction from a lock lever of the drum unit when the developer cartridge is attached to the drum unit, the first boss is supported by the support surface of the first side plate of the drum unit, and the first boss bears the weight of the developer cartridge, and
• wherein the developer cartridge rotates about the first boss in response to the second boss receiving the pressing force directed from the second end to the first end in the first direction.