A replaceable unit for an electrophotographic image forming device includes a housing having a reservoir for holding toner. An electrical connector is positioned on a first side of the housing. The electrical connector includes an electrical contact for contacting a corresponding electrical contact in the image forming device and a magnetic sensor electrically connected to the electrical contact. The electrical connector is movable between a first position and a second position. When the electrical connector moves from the first position to the second position, the electrical contact of the replaceable unit moves from a retracted position to an operative position. When the electrical connector moves from the first position to the second position, the magnetic sensor moves from a misaligned position to an aligned position with a point in a path of movement of a magnet for sensing a magnetic field of the magnet.

A material cartridge includes a first unit including a first attachment portion, a second unit and a first memory unit. The first memory unit that is attached to the first attachment portion and includes a first electrode and a first storage element. A cartridge reproduction method includes: detaching the first memory unit from the first attachment portion; attaching an electrode unit to the first attachment portion, the electrode unit including a second electrode, the second electrode configured to be brought into contact with a main body electrode of an image forming apparatus so as to be electrically connected to the main body electrode; and attaching, to the first unit, an element unit including a second storage element configured to be electrically connected to the second electrode. The element unit is located in a gap formed between the first unit and the second unit.

A toner container includes a container body, an opening, a cover, a toner discharge port, a shutter, a cylindrical structure, protrusions, and an identifier. The shutter is attached to the cover and includes a main shutter covering the toner discharge port. The main shutter moves between a closed position to close the toner discharge port and an open position to open the toner discharge port. The protrusions are on both sides of the cover and protrude in a direction orthogonal to a toner container mounting direction. The identifier is on the cover to indicate a toner color. The cylindrical structure's leading end is downstream of leading ends of the protrusions in the mounting direction. The main shutter's leading end is downstream of the protrusions' leading ends in the mounting direction when the main shutter is in the closed position. The protrusions are downstream of the identifier in the mounting direction.

A developing cartridge includes a casing, a developer-carrying member, a supply member, a developing electrode, a supply electrode, and an insulating member. The casing is configured to accommodate therein developer. The developer-carrying member is configured to rotate about a rotational axis and carry the developer thereon. The supply member is configured to supply the developer to the developer-carrying member. The developing electrode is configured to be electrically connected to the developer-carrying member. The supply electrode is configured to be electrically connected to the supply member. The insulating member insulates the developing electrode and the supply electrode with each other. The developing electrode, the insulating member, and the supply electrode are overlapped in this order in an axial direction of the rotational axis.

A developing cartridge includes a casing, a developer-carrying member, a supply member, a developing electrode, a supply electrode, and an insulating member. The casing is configured to accommodate therein developer. The developer-carrying member is configured to rotate about a rotational axis and carry the developer thereon. The supply member is configured to supply the developer to the developer-carrying member. The developing electrode is configured to be electrically connected to the developer-carrying member. The supply electrode is configured to be electrically connected to the supply member. The insulating member insulates the developing electrode and the supply electrode with each other. The developing electrode, the insulating member, and the supply electrode are overlapped in this order in an axial direction of the rotational axis.

A photosensitive member unit includes a photosensitive member, a transfer roller, a mounting portion capable of mounting a development unit including a development roller, a first gear and a second gear each provided at one end of the photosensitive member in an axial direction of the photosensitive member, and a third gear provided at one end of the transfer roller in an axial direction of the photosensitive member and configured to engage with the second gear. The first gear, the second gear, and the third gear are helical gears. A direction in which helical teeth of the first gear are inclined is opposite to a direction in which helical teeth of the second gear are inclined, and the direction in which the helical teeth of the first gear are inclined matches a direction in which helical teeth of the third gear are inclined.

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 toner container includes a container body, an opening, a cover, a toner discharge port, a shutter, a cylindrical structure, protrusions, and an identifier. The shutter is attached to the cover and includes a main shutter covering the toner discharge port. The main shutter moves between a closed position to close the toner discharge port and an open position to open the toner discharge port. The protrusions are on both sides of the cover and protrude in a direction orthogonal to a toner container mounting direction. The identifier is on the cover to indicate a toner color. The cylindrical structure's leading end is downstream of leading ends of the protrusions in the mounting direction. The main shutter's leading end is downstream of the protrusions' leading ends in the mounting direction when the main shutter is in the closed position. The protrusions are downstream of the identifier in the mounting direction.

A developing cartridge includes a storage medium. A first contact portion is provided in a photoconductor unit and configured to be electrically connected to the storage medium. A second contact portion is provided in an apparatus body. The photoconductor unit is configured to, in a case of attaching the photoconductor unit to the apparatus body, move from a first position to a second position while being guided by a guide member and then move from the second position to a third position below the second position. At least one of the first contact portion and the second contact portion is capable of being displaced such that engagement between the first contact portion and the second contact portion is performed while the photoconductor unit moves by being guided by the guide member, and the engagement is maintained while the photoconductor unit moves from the second position to the third position.

A developing cartridge includes a casing, a developer-carrying member, a supply member, a developing electrode, a supply electrode, and an insulating member. The casing is configured to accommodate therein developer. The developer-carrying member is configured to rotate about a rotational axis and carry the developer thereon. The supply member is configured to supply the developer to the developer-carrying member. The developing electrode is configured to be electrically connected to the developer-carrying member. The supply electrode is configured to be electrically connected to the supply member. The insulating member insulates the developing electrode and the supply electrode with each other. The developing electrode, the insulating member, and the supply electrode are overlapped in this order in an axial direction of the rotational axis.