Image forming apparatus and developer cartridge

摘要

A cartridge includes a housing configured to store a developing agent, an engagement gear rotatably provided to the housing and including a first engaging portion, a rotational body rotatably provided so as to be coaxial with the engagement gear and including a second engaging portion configured to engage the first engaging portion in response to rotation of the engagement gear. The rotational body is configured to be rotatable following the rotation of the engagement gear by the engagement of the first engaging portion and the second engaging portion. The cartridge further includes an extension portion provided at a position shifted from a center of rotation of the rotational body and protruding outside of the housing. The engagement gear and the rotational body selectively take a first state where the first engaging portion and the second engaging portion are separated from each other or a second state where the first engaging portion and the second engaging portion are engaged with each other.