An image forming apparatus includes a print engine, a waste toner collecting device, and a waste toner transfer auger. The waste toner collecting device includes a waste toner container, a sensor disposed on one side of the waste toner container, and a rotatable dispersing member which moves waste toner flowing into the waste toner container to another side of the waste toner container.

A toner cartridge includes: a casing having a first toner accommodating portion and a second toner accommodating portion; an agitator; an auger; a first protrusion positioned at one side in a first direction of the second toner accommodating portion; a second protrusion positioned at another side in the first direction of the second accommodating portion; a memory; and a toner-side electrical contact surface electrically connected to the memory. The toner cartridge is attachable to a drum cartridge by the casing pivotally moving from a first position to a second position relative to the drum cartridge about the first protrusion and the second protrusion. When the casing is at the first position, the toner-side electrical contact surface does not contact a first electrical contact surface of the drum cartridge. When the casing is at the second position, the toner-side electrical contact surface contacts the first electrical contact surface.

An image forming apparatus includes an apparatus body, a developer container, a data recording medium, a contact terminal, a detector, and control circuitry. The developer container is detachably attached in the apparatus body. The data recording medium is on the developer container. The contact terminal is disposed in the apparatus body and contacts the data recording medium. The detector detects a communication failure between the data recording medium and the apparatus body. The control circuitry executes a control mode to vibrate the data recording medium when the detector detects the communication failure.

An image forming apparatus including a housing, a toner cartridge, and a drum unit. The drum unit is movable through the opening between an accommodated position where the drum unit is positioned in the housing and a pulled-out position where the drum unit is pulled out of the housing. The drum unit includes a photosensitive drum and a developing unit. The photosensitive drum is rotatable about a first axis extending in a second direction. The developing unit includes a magnetic roller, a developer container, a first auger and a second auger. The magnetic roller is positioned between the toner cartridge and the photosensitive drum. The magnetic roller faces a surface of the photosensitive drum. The developer container is formed with an inlet allowing the toner to be replenished from the toner cartridge. The first auger is positioned in the developer container. The second auger is positioned in the developer container.

An image forming apparatus includes an image bearer, a developing device, a fixing device, and circuitry. The developing device contains a developer and develops a latent image on the image bearer with the developer. The developing device includes a stirrer to stir the developer. The fixing device fixes a toner image onto a sheet. The circuitry performs start-up operations after receiving a print start command and before starting a printing operation. The start-up operations includes starting a warm-up operation of the fixing device and starting, during the warm-up operation, a stirring operation in which the stirrer stirs the developer.

A developing cartridge may include: a casing; a developing roller extending in a first direction; a developing-roller gear; a coupling including a coupling gear; a first idle gear; a second idle gear; an agitator; a first agitator gear; and a protrusion. The developing-roller gear, the coupling, the first idle gear, the second idle gear, the first agitator gear, and the protrusion may be positioned at an outer surface of the casing. The protrusion may be positioned between a first axis of the coupling and a third axis of the first agitator gear in a second direction connecting the first and third axes. The protrusion may be positioned outside an addendum circle of the developing-roller gear, an addendum circle of the coupling gear, an addendum circle of the first idle gear, and an addendum circle of the second idle gear. The first agitator gear may be spaced apart from the protrusion in the first direction.

A developing device includes a developer carrying member and first and second conveyance members. The first conveyance member conveys a developer in a first direction through a first conveyance path to the developer carrying member. The second conveyance member conveys the developer in a second direction through a second conveyance path included in a circulation path along with the first conveyance path. The second conveyance member has a helical second screw around a second shaft. The second conveyance path includes a developer replenishing port and a developer discharge port. The second screw is approximately constant in diameter in a second section being a portion extending a predetermined distance from an end of the discharge port in the second direction when viewed in a top view. The second screw conveys the developer at a lower speed in the second section than on an upstream side with respect to the second section.

A powder conveying device includes a first conveyor, a first conveyance passage, a fall passage, a second conveyor, and a second conveyance passage. The first conveyor conveys powder in a substantially horizontal direction and is disposed in the first conveyance passage. The powder output from an outlet port of the first conveyance passage is to fall in the fall passage. The second conveyor conveys the powder in the substantially horizontal direction and is disposed in the second conveyance passage that has an inlet port to receive the powder falling in the fall passage. When viewed in a cross section orthogonal to a powder conveyance direction, a cross-sectional area of a space that is not occupied by the first conveyor in the first conveyance passage is larger than a cross-sectional area of a space that is not occupied by the second conveyor in the second conveyance passage.

A toner container includes a first rotation member rotatably provided in a container main body, a stirring member rotatably provided in such a way as to be parallel to the first rotation member, a lid member closing an opening portion of the container main body, a first bearing portion provided on an inner surface of the lid member and rotatably supporting a first end portion of a first rotation shaft of the first rotation member, a stirring bearing portion provided on the inner surface of the lid member and rotatably supporting a lid-side end portion of a stirring rotation shaft of the stirring member, a storage concave portion formed on the lid member and recessed from an outer surface of the lid member inward, and a transmission mechanism provided in the storage concave portion to transmit a rotation of the first rotation shaft to the stirring rotation shaft.

A toner container includes an elongated container main body, a toner discharge port, a first rotation member configured to convey the toner toward the toner discharge port, a support plate provided in the container main body and disposed in such a way as to face the wall surface, and an opening and closing member provided between the wall surface and the support plate and supported by the support plate in such a way as to be able to move between a closing position and an opening position. The support plate includes a first opening portion formed at a position corresponding to the toner discharge port and larger than the toner discharge port in size, and a film member attached to the support plate in such a way as to cover the first opening portion and including a second opening portion formed at a position corresponding to the toner discharge port.