An image forming apparatus includes an image bearing member, a developing device, a supplying device, and a control unit. The image bearing member bears a latent image. The developing device develops the latent image with a toner. The supplying device supplies toner to the developing device. The control unit executes a discharge operation to consume toner transferred onto the image bearing member from the developing device without transferring the toner onto a recording medium. The control unit executes the discharge operation where first deterioration integrated information exceeds a first executing threshold, and where second deterioration integrated information exceeds a second executing threshold that is larger than the first executing threshold. The control unit acquires the first deterioration information based at least a first deterioration threshold, and acquires the second deterioration information based on at least a second deterioration threshold that is larger than the first deterioration threshold.

A toner collecting device includes an exhaust path and a catching installation. Through the exhaust path, air containing a floating toner is passed. The catching installation is configured to catch the floating toner from the air passing through the exhaust path. The catching installation is formed by overlapping a plural of filters each having a different mesh size.

A developing device includes a container that contains a developer including a carrier and a toner; a transport member that is rotatably disposed in the container and that agitates and transports the developer in a rotation-axis direction thereof; a discharge outlet that has an opening in a side wall of the container facing in a direction perpendicular to the rotation-axis direction, the discharge outlet allowing the developer to be discharged to an outside of the container when a height of a surface of the developer becomes greater than a height of a lower surface of the discharge outlet; and a magnetic member that is disposed at a position that is above the lower surface of the discharge outlet and that overlaps the lower surface in an up-down direction, the magnetic member attracting a part of the developer that is lifted up by the transport member.

A toner cartridge includes a toner supply pipe and a first shutter. The toner supply pipe has a toner supply opening. When the toner cartridge is mounted onto a main unit, the toner supply pipe moves through an insertion opening from an outside position at which the toner supply opening is located outside a developing frame to an inside position at which the toner supply opening is located inside the developing frame. The first shutter is provided at the toner supply pipe. The first shutter moves relative to the toner supply pipe between an open position at which the toner supply opening is opened and a closed position at which the toner supply opening is closed. The first shutter moves relative to the toner supply pipe from the closed position to the open position in a state where the toner supply pipe is located at the inside position.

A developing device includes a developer holder that holds developer, the developer holder being disposed so as to oppose an image holder that holds a latent image and developing the latent image with the developer; a housing that accommodates the developer holder with the developer holder being exposed from an opening portion; a wall section that is provided over an entire region in an axial direction of the developer holder from an edge portion, which is a downstream side in a rotation direction of the developer holder, of the opening portion of the housing, the wall section having an opposing surface that opposes an outer peripheral surface of the image holder to form a gap; and a blocking member that is disposed on one side of the opposing surface in the axial direction and that blocks part of the gap.

A powder conveying device includes a drop conveyance passage, an intersecting conveyance passage, a conveying screw, and a floating member. Powder entering from an inflow port drops in the drop conveyance passage. The intersecting conveyance passage communicates with a lower end of the drop conveyance passage and extends in an intersecting direction that intersects the drop conveyance passage. The conveying screw is disposed in the intersecting conveyance passage and rotates in a specified direction to convey the powder in the intersecting direction. The floating member is movably installed in the drop conveyance passage and floats in the drop conveyance passage to move by contact with the conveying screw. The inflow port and the floating member interfere with each other to prevent the floating member from coming out of the inflow port of the drop conveyance passage.

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.

An image formation apparatus according to an embodiment may include: an image formation section to form an image with a developer; an entire area printing rate calculator configured to calculate an entire area printing rate, which is, a printing rate of an entirety of an image formation area; a divided area printing rate calculator configured to calculate each divided area printing rate, which is, a printing rate of each of plural divided areas, divided in a main scanning direction, of the image formation area; and a deteriorated developer discarding operation execution section configured, when the entire area printing rate is equal to or lower than an entire area printing rate threshold, to perform a deteriorated developer discarding operation to discard the developer in any one of the divided areas in which the divided area printing rate is equal to or lower than a divided area printing rate threshold thereof.

An image formation device includes: an image formation section configured to develop, using toner, an electrostatic latent image formed on an image carrier based on job image information, thereby transferring a first image onto continuous paper; a hardware processor configured to determine whether or not a serial printing distance is equal to or shorter than a first threshold, wherein the serial printing distance is a distance at which the first image is printed on the continuous paper, and control the image formation section to print the first image on the continuous paper when the serial printing distance is equal to or shorter than a first threshold, and to decrease the proportion of deteriorated toner in a developer by printing the first image and a second image on the continuous paper when the serial printing distance exceeds a first threshold, wherein the second image is based on an image information.

A developing device includes a developing container, a rotatable member including a first screw portion and a second screw portion, a first feeding path configured to accommodate the first screw portion, a second feeding path provided in communication with the first feeding path at a position downstream of the second screw portion with respect to a develop feeding direction, and a developer discharging opening provided in the second feeding path. In a state in which the developing device is mounted to the image forming apparatus, in a cross section of the second feeding path perpendicular to a rotational axis of the rotatable member, the second feeding path includes a region where a distance between side surfaces of the second feeding path in a side above a center of a rotation shaft of the rotatable member with respect to a vertical direction increases upwardly.