An image forming apparatus includes a release processing portion, a regulation processing portion, and a second restriction processing portion. The release processing portion releases regulation on removal of a developer storage portion when a storage amount of developer stored in an image forming portion is equal to or smaller than a second threshold smaller than a first threshold. The regulation processing portion regulates removal of the developer storage portion when the storage amount of the developer stored in the image forming portion is larger than the second threshold and removal of the developer storage portion has not been regulated. The second restriction processing portion imposes restriction on processing of the regulation processing portion when the regulation on the removal of the developer storage portion is released and a restriction condition is satisfied.

A toner cartridge includes a casing accommodating toner and provided with a toner discharge opening, a fan, a closing member capable of shifting between a closed position and an open position for opening a passage. The toner cartridge also includes a drive receiving member for receiving a driving force from outside of the toner cartridge and for transmitting the driving force toward the fan and the closing member by rotation thereof. The closing member periodically moves between the closed position and the open position by receiving the driving force.

A powder container includes a powder chamber for containing powder for forming images, a powder outlet formed in a face of the powder container, and a shutter assembly to open and close the powder outlet and including first and second shutters. The first shutter is movable between a sealing position to close the powder outlet and an open position to open the powder outlet and includes a pressed member to cancel retention of the first shutter at the sealing position. The second shutter includes a pressing projection that interferes with the pressed member of the first shutter and is movable between a shielding position to cover the pressed member without interference between the pressing projection and the pressed member and a releasing position to press the pressed member with the pressing projection.

A powder container includes a powder chamber for containing powder for forming images, a powder outlet formed in a face of the powder container, and a shutter assembly to open and close the powder outlet and including first and second shutters. The first shutter is movable between a sealing position to close the powder outlet and an open position to open the powder outlet and includes a pressed member to cancel retention of the first shutter at the sealing position. The second shutter includes a pressing projection that interferes with the pressed member of the first shutter and is movable between a shielding position to cover the pressed member without interference between the pressing projection and the pressed member and a releasing position to press the pressed member with the pressing projection.

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 housing having an opening, a cover configured to openably close the opening, photosensitive drums, cartridges, a first motor and a controller. Each cartridge has a developing roller, a storage chamber configured to store toner, and an agitator configured to agitate the toner. The first motor is configured to rotate the agitators. The controller rotates the agitators by rotating the first motor when forming an image on a sheet. The controller determines whether a new cartridge is included in the plurality of cartridges in response to the image forming apparatus being turned on or in response to the cover being closed. In a case where a new cartridge is included, the controller stirs toner with the agitators by rotating the first motor. In a case where a new cartridge is not included, the controller does not stir the toner.

An image forming apparatus includes: an image carrier configured to carry an image; a developing unit configured to develop the image carried by the image carrier with a developer; and a developer replenishing unit configured to supply the developer to the developing unit, the developer replenishing unit being configured to predict, in advance, an amount of developer consumed by the image carrier at a start or an end of image formation apart from developer consumed in the image formation, to replenish the predicted amount of the developer.

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 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.

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.