Developer cartridge provided with gear having engagement portions

A developing cartridge comprising:

• a developing roller rotatable about a first axis extending in a first direction;
• a housing configured to accommodate developer therein;
• a coupling rotatable about a second axis extending in the first direction and positioned at one side of the housing in the first direction;
• a gear rotatable about a third axis extending in the first direction from a first rotational position to a second rotational position, from the second rotational position to a third rotational position, and from the third rotational position to a fourth rotational position, the gear being rotatable in accordance with a rotation of the coupling, the gear being positioned at the one side of the housing in the first direction;
• and
• a protrusion movable in accordance with a rotation of the gear,
• wherein the protrusion moves at a first speed in a case where the gear rotates from the first rotational position to the second rotational position,
• wherein the protrusion moves at a second speed in a case where the gear rotates from the third rotational position to the fourth rotational position, and
• wherein the second speed is different from the first speed.