A first contact portion provided on a first shutter member that opens and closes a receiving port for receiving a developer from a cartridge and a second contact portion provided on the cartridge are configured to contact each other in an attachment and detachment direction of the cartridge so that the first shutter member is in a position at which the receiving port is opened. The first shutter member is urged by a first urging member so that a contacting state between the first contact portion and the second contact portion is maintained until a second shutter member that opens and closes a supplying port of the cartridge closes the supplying port when the cartridge is discharged from the apparatus body.

A developing cartridge may include: a casing to accommodate developer; a storage medium including an electric contact surface; an elastic member extending in a first direction crossing the electric contact surface, and configured to be compressed or stretched in the first direction between a first state and a second state; and a holder including an outer surface positioned toward a side of the holder in the first direction, the electric contact surface positioned at the outer surface, and movable between first and second positions in the first direction relative to the casing. A length of the elastic member in the first direction is greater in the first state than in the second state. The electric contact surface is in the first position when the elastic member is in the first state, and the electric contact surface is in the second position when the elastic member is in the second state.

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 toner cartridge includes a housing having a first combining portion and a front cover attached to a front end of the housing in a longitudinal direction, wherein the front cover includes a first locking portion to which the first combining portion is to be attached and a notch portion provided in the first locking portion so that the first locking portion is breakable by an external force in a direction in which the front cover is spaced apart from the housing in the longitudinal direction.

A toner cartridge includes: a housing to accommodate toner and including a fastening boss at a front end; a front cover including a fastening hole aligned with the fastening boss; a fastening member including a fastening portion and a head portion, the fastening portion configured to pass through the fastening hole and be fastened to the fastening boss to couple the front cover to the housing; and a separating portion to allow the fastening hole to be separated from the head portion of the fastening member by an external force acting on the front cover.

A toner cartridge according to one example includes first and second alignment guides that extend outward from a first side and a second side of the toner cartridge, respectively, for positioning the toner cartridge. The first and second alignment guides define a pivot axis about which the toner cartridge is pivotable relative to an imaging unit when the toner cartridge is installed on the imaging unit. An engagement member is positioned on a rear of the toner cartridge for receiving a bias force for biasing the toner cartridge about the pivot axis when the toner cartridge is installed on the imaging unit. The engagement member is positioned next to the bottom of the housing. The engagement member includes an angled contact surface that faces upward and rearward for contacting a corresponding hold-down on the imaging unit when the toner cartridge is installed on the imaging unit.

A developer cartridge including a housing to contain a developer and including a developer outlet from which the developer is dischargeable. A transport member is arranged inside the housing to rotate to transport the developer to the developer outlet. A volume adjustment member is insertable inside the transport member opposite to the developer outlet to adjust an inside volume of the housing.

A toner cartridge includes a photoconductive drum and a boss that protrudes outward from a first longitudinal end of the toner cartridge at a rotational axis of the photoconductive drum. An outermost axial segment of the boss along the rotational axis includes a partial cylinder having a cross-sectional shape of a circular segment. An outer circumferential surface of the partial cylinder is convex to a bottom of the toner cartridge and forms a bottom contact surface of the boss that is unobstructed to contact and sit in a corresponding V-block in an image forming device when the toner cartridge is installed in the image forming device. The outermost axial segment of the boss includes clearance above a topmost portion of the partial cylinder and within the radius of the outer circumferential surface of the partial cylinder permitting the clearance to accommodate one or more features in the image forming device.

An assembly for use in an electrophotographic image forming device includes a housing having a reservoir for holding toner. The housing includes a wall having an inner surface forming a boundary of the reservoir and an outer surface opposite the inner surface. A toner agitator is positioned in the reservoir and has a rotatable shaft. The shaft includes an end portion that passes through an opening in the wall. A gear is mounted on the end portion of the shaft outside of the reservoir and is rotatably coupled to the shaft. An annular seal encircles and is in contact with an outer circumferential surface of the shaft. The annular seal is positioned between an inner axial face of the gear and the outer surface of the wall. The inner axial face of the gear contacts the annular seal and presses the annular seal against the outer surface of the wall.

An image forming apparatus includes a body on which a development cartridge is mountable to form a toner image by supplying toner in the development cartridge to an electrostatic latent image formed, a communicating portion provided on an outer surface of the body to be coupled with a toner refill cartridge to form a connection with the development cartridge to perform a toner refill of the toner in the development cartridge through the connection with the development cartridge, a sensor to detect a remaining toner amount remaining in the development cartridge, and a controller to estimate, based on the sensor detecting the remaining toner amount, an estimated toner remaining rate of the development cartridge, which is an estimated rate of the toner remaining in the development cartridge based on toner consumption, according to the toner refill.