An image forming apparatus, having process units, a transfer unit, a motor, first through fourth cams, a color-linkage gear train, a monochrome-transmission gear train, and a color-transmission gear train, is provided. Each of the process units has a developing unit including a developing roller and a drum unit including a photosensitive drum. The color-linkage gear train rotates the first cam, the second cam, and the third cam in shifted phases. The monochrome-transmission gear train transmits a driving force from the motor to a monochrome clutch, which engages and disengages transmission of the driving force from the monochrome-transmission gear train to the fourth cam. The color-transmission gear train transmits the driving force from the motor to a color clutch, which engages and disengages transmission of the driving force from the color-transmission gear train to the color-linkage gear train.

A rotational force is transmitted to a main assembly side feeding member for feeding the toner into a main assembly side toner accommodating portion from a coupling member provided on a cartridge.

The cartridge includes a photosensitive drum, a discharge opening configured to discharge the toner removed from the photosensitive drum toward the main assembly side feeding member, and a coupling member configured to transmit the rotational force to the main assembly side feeding member. The coupling member is movable between a first position for transmitting the rotational force to the main assembly side feeding member and a second position retracted from the first position.

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 drum unit includes: a frame; a first photosensitive drum; a second photosensitive drum; a charger; and a storage medium. The frame includes: a first frame plate; a second frame plate spaced apart from the first frame plate in a first direction; a third frame plate connecting one end of the first frame plate to one end of the second frame plate; and a fourth frame plate connecting another end of the first frame plate to another end of the second frame plate. The first photosensitive drum and the second photosensitive drum are rotatably supported by the frame. The second photosensitive drum is spaced apart from the first photosensitive drum and positioned closer to the third frame plate than the first photosensitive drum to the third frame plate in a second direction. The storage medium has an electrical contact surface positioned at an outer surface of the third frame plate.

In one example, a detachable adapter to adapt a drive shaft on a printer to a drive mechanism on a toner cartridge and to transmit rotation of the drive shaft to the drive mechanism. The adapter includes a cylindrical part having a first end and a second end opposite the first end, the first end configured to detachably receive and engage an end of the drive shaft so that the part will rotate with the drive shaft when the part is attached to the drive shaft, and a driver mounted to or integral with the second end and configured to drivingly connect the part to the drive mechanism on the toner cartridge when the part is attached to the drive shaft and the toner cartridge is installed in the printer.

A cartridge detachably mountable to a main assembly of an electrophotographic image forming apparatus, the cartridge includes (i) a rotatable developing roller for developing a latent image formed on a photosensitive member; (ii) a first drive transmission member capable of receiving a rotational force originated by the main assembly; (iii) a second drive transmission member capable of coupling with the first drive transmission member and capable of transmitting the rotational force received by the first drive transmission member to the developing roller; and (iv) a coupling disconnection member including a force receiving portion capable of receiving the force originated by the main assembly, and an urging portion capable of urging at least one of the first drive transmission member and the second drive transmission member by the force received by the force receiving portion to separate one of the first drive transmission member and the second drive transmission member from the other, thereby disconnecting the coupling.

According to one embodiment, an image forming apparatus includes a plurality of parts, an acquisition unit, and a control unit. The plurality of parts are used in the image forming process and are replaced according to the degree of use. The acquisition unit acquires, for each of the parts, use-related information that is information indicating the degree of use of the plurality of parts. The control unit determines the replacement timing of the part using the plurality of pieces of use-related information acquired by the acquisition unit and the determination condition regarding the replacement timing of the part.

A process cartridge configured to be detachably installed to a main body of the imaging device includes a housing, and a photosensitive drum arranged in the housing. A drive coupler configured to receive a driving force from a drive head of the main body of the imaging device is provided at an end of the photosensitive drum. The process cartridge can be installed to the main body of the imaging device or be detached from the main body of the imaging device in a manner that the photosensitive drum rotation axis forms a variable included angle with respect to the drive head rotation axis. The installation of the process cartridge is facilitated, and the engagement of the drive coupler with the drive head of the imaging device is facilitated.

A process cartridge including: a photosensitive member cartridge including a photosensitive member; and a developing cartridge including a developer carrier. The developing cartridge further includes: an inputting portion; a first cover; and a second cover. The first cover has a first engagement portion configured to move the developer carrier away from the photosensitive member. The first engagement portion is positioned between an axis of the developer carrier extending in an axial direction and an axis of the inputting portion extending in the axial direction, when projected in the axial direction. The second cover has a second engagement portion configured to move the developer carrier away from the photosensitive member. The second engagement portion is positioned between the axis of the developer carrier and the axis of the inputting portion, when projected in the axial direction.

A developing cartridge includes: a casing; a developing roller; a shaft; and a cam. The casing is configured to accommodate developer therein. The developing roller is rotatable about a first axis extending in an axial direction. The shaft extends along a second axis extending in the axial direction. The shaft is movable along the second axis. The cam is movable along the second axis in response to axial movement of the shaft. The cam has a cam surface non-parallel with the second axis.