A development cartridge which is mountable in an image forming apparatus includes a toner container portion to store toner and a toner refilling portion to receive, from a toner refill cartridge mountable to the toner refilling portion, toner to be stored in the toner container portion. The toner refilling portion includes an inlet shutter rotatable to an inlet position at which the toner is capable of being received by the toner refilling portion from the toner refill cartridge, and a shutter protrusion provided on a surface of the inlet shutter to, while the inlet shutter is rotated, contact an object and cause feedback indicating the inlet shutter is rotated to the inlet position.

An image forming apparatus includes a toner cartridge including a toner container with a supplying outlet and an engaged portion, and a shutter movable between an open position and a closed position, and an apparatus main body to and from which the toner cartridge is mounted and detached, the apparatus main body including a toner accommodation unit, a guide portion for guiding the toner cartridge, a pressing member pressing the toner cartridge in the detaching direction, an engaging member movable between an engaging position and an engagement release position, the engaging member allowing movement of the toner cartridge from the first position toward the second position in a case where the engaging member is at the engagement release position, and a damping force applying mechanism applying damping force to the toner cartridge.

Examples of the present disclosure relate to a base for a printing material container. The base has a channel structure defining an opening of the base, an axis of the channel structure defining an axial direction. The base also has a material-guiding structure, formed around the opening, having a helical lower surface that extends from the channel structure in the axial direction. An upper surface of the material-guiding structure is formed by a lower surface of the base and the helical lower surface meets the lower surface of the base at a curved side wall that extends radially from the channel structure to an annular portion of the base.

A powder accommodating container includes a powder accommodating portion that accommodates powder, a sealing section that openably seals a supply port by being removed from the powder accommodating portion, and a breaking section that has a film-shaped member that breaks the powder in the powder accommodating portion by being removed from the powder accommodating portion in a case of opening the supply port, is fixed to plural places in the powder accommodating portion such that the film-shaped member is removable, and is fixed to the powder accommodating portion such that a force required for removing a tip of the film-shaped member from the powder accommodating portion is larger than other portions.

A developing device includes a developer cartridge and a developing unit. The developer cartridge, in some instances, may include a shutter. This shutter may have a wall for closing a developer supply hole, and be movable, with respect to a developer cartridge casing, between an open position where the supply hole is opened by the wall and a closed position where the supply hole is closed by the wall. The shutter may further include a protrusion that is movable with respect to the wall of the shutter between a first position and a second position in an axial direction. The protrusion, in the first position, is engageable with a developing unit and, in the second position, would be disengaged from the developing unit.

A toner storage apparatus to which a toner cartridge is mountable by being moved in a moving direction includes a toner storage frame that has a reception port and a seal attachment surface, stores toner supplied from the cartridge via the reception port, and has a protrusion from the attachment surface, and a seal portion that is attached to the attachment surface, has a rubbing surface that rubs against the cartridge when the cartridge is moved in the moving direction, and has a communication hole with the reception port. At least part of the protrusion is inside the communication hole and upstream of the reception port in the moving direction. An end of the protrusion is closer to the attachment surface than the rubbing surface in a direction perpendicular to the attachment surface. The seal portion contacts an outer peripheral surface of the protrusion extending in the perpendicular direction.

An image forming apparatus includes an image forming portion, a first release processing portion, and a second release processing portion. The image forming portion includes a storage portion storing developer and forms an image by using the developer stored in the storage portion. The first release processing portion releases regulation on removal of a developer storage portion when a storage amount of the developer stored in the storage portion is equal to or smaller than a second threshold smaller than a first threshold. The second release processing portion releases the regulation on the removal of the developer storage portion based on the remaining amount of the developer that is acquired when the storage amount of the developer stored in the storage portion is larger than the second threshold.

An image forming apparatus includes an image bearing member, a replenishment unit, an agitation member, a drive source, a control unit, a memory unit, and a remaining amount detection unit. The control unit performs (1) a first operation to drive the drive source for a first time in a case where it is judged based on the output value of the remaining amount detection unit that the toner has increased, and (2) a second operation to drive the drive source for a second time that is shorter than the first time in a case where it is judged based on the output value of the remaining amount detection unit that the toner has not increased.

A toner cartridge includes a pump portion that is variable in volume, a feeding path portion including a connection opening connected to the pump portion at a first end and including a discharge opening at a second end, and a toner accommodating portion connected to an intermediate portion between the first end of the feeding path portion and the second end of the feeding path portion. A volume change amount of the pump portion is greater than a total volume from the connection opening to the discharge opening.

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.