In a cartridge, a housing has a developer accommodating portion and includes a first side wall and a second side wall. A coupling member is disposed at a position opposite to the developer accommodating portion with respect to the first side wall. A detection body is disposed at a position opposite to the developer accommodating portion with respect to the second side wall. A first driving force transmission member is positioned at the same side with the coupling member with respect to the first side wall, and transmits driving force from the coupling member to a rotating member. A second driving force transmission member is positioned at the same side with the detection body with respect to the second side wall, and transmits driving force from the rotating member to the detection body.

A cartridge is mountable in and dismountable from a main assembly of an image forming apparatus, in which the main assembly includes an opening and an openable member including a discriminating portion. The cartridge includes a process unit including a rotatable photosensitive member and a developing roller configured to supply toner to the photosensitive member, and a developer storage unit configured to store a developer. The developer storage unit is provided with a discharge opening for permitting discharge of the stored developer to the process unit and is mountable to and dismountable from the process unit. The developer storage unit is provided with a portion-to-be-discriminated provided so as to be engaged with the discriminating portion of the openable member when the cartridge is mounted in the main assembly and the openable member is in a closed position.

A developing cartridge is provided. The developing cartridge includes a housing which accommodates developer therein, a receiving member provided which couples with a force output member of an image forming apparatus to receive a driving force, a developing roller which rotates by the driving force received by the receiving member; a detectable rotary member having a first detectable portion and a second detectable portion and rotates by the driving force from a first rotational position where the first detectable portion is detected by a detection member provided in the image forming apparatus to a second rotational position where the second detectable portion is detected by the detection member, and a cut-off mechanism which cuts off a transmission of the driving force from the receiving member to the detectable rotary member in a state where the detectable rotary member is positioned in the second rational position.

A developing cartridge may include: a casing configured to accommodate developer therein, the casing extending in the first direction; a coupling rotatable about a first axis extending in the first direction, the coupling being positioned at one side of the casing in the first direction; a detection gear rotatable about a second axis extending in the first direction, the detection gear being positioned at another side of the casing in the first direction; and a storage medium including an electric contact surface, the electric contact surface being positioned at the one side of the casing in the first direction.

A developing cartridge includes a developing electrode and a supply electrode. The developing electrode includes a first electrical contact in contact with a developing roller shaft, and a second electrical contact positioned closer to the developing roller shaft than a second agitator gear is to the developing roller shaft. The second electrical contact is positioned farther from the developing roller shaft than the first electrical contact is from the developing roller shaft. The supply electrode includes a first electrical contact in contact with the supply roller shaft, and a second electrical contact positioned closer to the developing roller shaft than the second agitator gear is to the developing roller shaft. The second electrical contact of the supply electrode is positioned farther from the developing roller shaft than the second electrical contact of the developing electrode is from the developing roller shaft.

A first gear cover has a first cover portion that covers an outer peripheral surface of a joint and that protrudes from a third outer surface in a first direction. A gear rotates about a third axis extending in the first direction by receiving driving force from coupling, and is located at a second outer surface. A second gear cover covers at least part of the gear, and has a second cover portion protruding in the first direction, and is located at the second outer surface. A first protruding portion protrudes from the first cover portion in a second direction, and is located at an opposite side from the developing roller with respect to the joint in the second direction. A second protruding portion protrudes from the second cover portion in the second direction, and is located at a same position as the first protruding portion in the second direction.

An apparatus body of an image forming apparatus has a first guide portion having an inlet shape corresponding to an outer shape of an engagement portion provided in a cartridge when seen in an attachment direction of the cartridge to the apparatus body and guiding the engagement portion, a second guide portion for guiding a positioning target portion which is provided on the cartridge for positioning an attachment completion position of the cartridge with respect to the apparatus body, and a movable member being at a regulation position at which a guiding path of the positioning target portion by the second guide portion is blocked is immovable from the regulation position unless being pressed by the engagement portion.

An apparatus body of an image forming apparatus has a first guide portion having an inlet shape corresponding to an outer shape of an engagement portion provided in a cartridge when seen in an attachment direction of the cartridge to the apparatus body and guiding the engagement portion, a second guide portion for guiding a positioning target portion which is provided on the cartridge for positioning an attachment completion position of the cartridge with respect to the apparatus body, and a movable member being at a regulation position at which a guiding path of the positioning target portion by the second guide portion is blocked is immovable from the regulation position unless being pressed by the engagement portion.

An image forming apparatus includes an apparatus body, a toner cartridge, a replaceable part, a controller and an apparatus body memory. An operating mode of the controller is set to one of a subscription mode and a normal mode. The controller is configured to perform processes in accordance with the set operating mode. The apparatus body memory is configured to store life information indicating a remaining life of the replaceable part attached to the apparatus body. The controller is configured to switch a control between: a control for allowing an extended use of the replaceable part; and a control for restricting the extended use of the replaceable part, according to the set operating mode. The extended use is defined as use of the replaceable part even after the replaceable part exceeds the remaining life indicated by the life information stored in the apparatus body memory.

In a cartridge, a developing roller is configured to rotate around a first rotational axis extending in a predetermined direction and to carry developer thereon, the developing roller having a first end and a second end apart from each other in the predetermined direction, a from-first-to-second direction being defined along the predetermined direction as being directed from the first end to the second end. A developing electrode is formed of a conductive material and is configured to be electrically connected to the developing roller, the developing electrode including a main part and a protruding portion protruding from the main part in the from-first-to-second direction. A detection body is formed of an insulating material and is rotatably supported by the protruding portion, the detection body including a first opening that exposes part of the protruding portion and a covering portion covering part of the protruding portion.