A drum cartridge includes: a photosensitive drum; a drum frame; a drum coupling; and an electrical contact surface. The photosensitive drum is rotatable about an axis extending in a first direction. The drum frame has one end portion in a second direction at which the photosensitive drum is positioned. The drum coupling is rotatable together with the photosensitive drum. The drum coupling is positioned at an outer surface of one side in the first direction of the drum frame. The electrical contact surface is positioned closer to another side in the second direction of the drum frame than the drum coupling is to the another side in the second direction of the drum frame.

The present disclosure provides an electrical parameter detection method, a chip, a consumable, and an image forming apparatus. The electrical parameter detection method includes: configuring an installation detecting pin to be at a high level by an image forming control unit; controlling a voltage of an installation detecting terminal to be at a low level by a chip control unit, such that a current loop is formed between the image forming apparatus and the chip; and determining, by the image forming apparatus, whether the image forming apparatus is in a desired contact with the chip according to an electrical parameter of the current loop.

A cartridge mountable to a printer, said printer including a coupling guide contactable to a coupling of the cartridge to guide the coupling member. A case of the cartridge is provided with a hole for exposing a free end portion of the coupling to an outside of the cartridge, and a retracted portion provided in downstream of the hole with respect to the mounting direction of the cartridge. When the cartridge is mounted to a main assembly of the printer, the coupling guide enters the retracted portion from which the coupling member has retracted.

With a structure in which a coupling member includes a sphere providing a center of inclination (pivoting), a rotational force transmitted member has an opening have a diameter smaller than that of the sphere, and the coupling member is prevented from disengaging from rotational force transmitted member by contact of inner edge of the opening to the sphere, the inner edge of the opening may limit an inclinable (pivotable) angle range of the coupling member. In a state that a pin that is a shaft portion is inserted in a hole that is a through-hole provided in a coupling member, opposite end portions of the pin are supported by a driving side flange, which is a rotational force transmitted member. The coupling member, the driving side flange, and the pin are connected in this manner, and the pin contacts the inside of the hole without limiting the inclinable angle range.

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.

An image forming device, including: a housing; a drawer movable between an inside position at which the drawer is located inside the housing and an outside position at which the drawer is located outside the housing; a drum cartridge including a photoconductive drum and a developer roller and mountable on the drawer; and a toner cartridge storing toner to be supplied to the developer roller and mountable on the drawer, wherein the drum cartridge and the toner cartridge are mountable on the drawer in a state in which the drawer is located at the outside position, and wherein the drum cartridge and the toner cartridge are arranged in a drawer moving direction in which the drawer moves, in the state in which the drum cartridge and the toner cartridge are mounted on the drawer.

In a photosensitive drum, a drum flange is press-fitted to each end of a drum element tube. The drum flange includes a flange facing the drum element tube, and a press-in boss formed on a drum-facing surface side of the flange and press-fitted to the inner circumferential side of the drum element tube. The outer circumferential surface of the press-in boss is configured so that partial cylindrical surfaces to be in contact with the inner circumferential surface of the drum element tube and oppositely-facing partial cylindrical surfaces not to be in contact with the inner circumferential surface of the drum element tube are alternately formed along the circumferential direction. First openings formed to penetrate at least a part of the press-in boss are respectively provided on the proximal end side of the partial cylindrical surfaces in the press-in boss.

An image forming apparatus is provided with an image holder that holds an electrostatic latent image, a developing unit that develops the electrostatic latent image of the image holder, a biasing unit that biases the developing unit toward the image holder; and a holding member that holds the biasing unit and is disposed so that a part which is opposite to a biasing direction of the biasing unit is in contact with an image forming apparatus main body directly or via another member.

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 fourth frame plate.

An image forming apparatus includes: a first guide that is provided in an apparatus housing and configured to suspend and hold a first unit including an image holder so that the first unit is movable in an insertion and removal direction; a second guide that is provided in the apparatus housing and configured to suspend and hold a second unit including a developer holder so that the second unit is movable in an insertion and removal direction; and a pedestal that is disposed on a front side in the insertion and removal direction with respect to the first guide and the second guide, supports, from below in a gravity direction, the first unit and the second unit while the first unit and the second unit are inserted into the apparatus housing, and does not contact with the first unit and the second unit located in the apparatus housing.