An image forming apparatus includes a development device, a toner storage part, a drive unit, a control unit, and an image carrying member. The development device includes a development casing, a developer carrying member, a first stirring transport member, a second stirring transport member, a discharge impeller, and a reverse transport impeller. The development casing includes a first partition wall, a communication part, a developer replenishment port, and a developer discharge part. The first stirring transport member includes a first rotation shaft and a first transport impeller. The second stirring transport member includes a second rotation shaft and a second transport impeller. The control unit can perform a developer discharge mode, in which the first rotation shaft and the second rotation shaft are rotated reversely during a non image formation period, so that the developer around the reverse transport impeller is discharged through the developer discharge part.

An image forming apparatus includes a rotatable image bearing member; a developing device including a rotatable developer carrying member, a toner content detecting portion, an electrostatic capacity detecting portion, and a switching portion configured to switch a developing condition on the basis of an output of the toner content detecting portion and an output of the electrostatic capacity detecting portion so that the developing condition is changed when the electrostatic capacity detected by the electrostatic capacity detecting portion reaches first electrostatic capacity at a first toner ratio and so that the developing condition is changed when the electrostatic capacity reaches second electrostatic capacity larger than the first electrostatic capacity at a second toner ratio smaller than the first toner ratio.

An example method of operating an image forming apparatus includes measuring a toner concentration supplied to a developing apparatus through a toner concentration sensor provided in the developing apparatus as a supply mode for supplying toner to the developing apparatus in the image forming apparatus is executed, increasing a driving speed of the developing apparatus when it is determined that the toner concentration has not reached a target toner concentration, measuring the toner concentration in the developing apparatus through the toner concentration sensor as the supply mode is executed in a state where the driving speed of the developing apparatus is increased, and determining an operating state of the image forming apparatus based on a remaining amount of toner when it is determined that the toner concentration has not reached the target toner concentration in the state where the driving speed of the developing apparatus is increased.

The technology described herein relates to double-stranded ribonucleic acid (dsRNA) compositions targeting the Serpina1 gene, and methods of using such dsRNA compositions to inhibit expression of Serpina1.

An approach is provided for monitoring and reporting capacity of a toner cartridge in a printing device. The printing device determines estimated toner levels based on actual toner levels obtained from a toner sensor of the printing device. The estimated toner levels are determined based on a first actual toner level and a second actual toner level obtained from the toner senor and print usage between the two actual toner levels. The estimated toner levels are determined for levels below the second actual toner level and are mapped to synthetic toner levels. Visual indications of the synthetic toner levels are displayed on the printing device.

A developing device includes a developing case, a toner concentration sensor, and a positioner. The developing case stores a developer containing toner and carrier to develop a latent image on a surface of an image bearer. The developing case includes at least a part of a conveyance path of the developer. The toner concentration sensor detects a toner concentration of the developer in the developing case. The positioner engages with an engaging portion at a center of a sensor main section of the toner concentration sensor to determine a position of the sensor main section in the developing case.

An amount-of-remaining-toner detecting device includes: a toner housing portion in which a toner bottle is housed, the toner bottle having a bottle body that is cylindrical and in which toner is housed, and a cap that is attached to one end of the bottle body in an axial direction of the bottle body and from which the toner housed in the bottle body is discharged; and circuitry configured to detect an amount of remaining toner in the toner bottle housed in the toner housing portion. The toner housing portion includes a first pair of electrodes facing each other with the bottle body interposed between the first pair of electrodes, and a second pair of electrodes facing each other with the bottle body interposed between the second pair of electrodes, at respective positions closer to the cap than the first pair of electrodes are. The circuitry detects the amount of remaining toner in the bottle body, based on at least one of a capacitance value between the first pair of electrodes or a capacitance value between the second pair of electrodes.

An image forming device may comprise: an attaching unit to which a removable toner bottle is attached; a toner storage that stores toner supplied from the toner bottle attached to the attaching unit; a detector that detects an empty state of toner in the toner storage; and a hardware processor that: supplies toner to the toner storage from the toner bottle when the toner bottle attached to the attaching unit is new; and switches a state of the toner bottle to an old state from a new state if the empty state detected by the detector is released.

An image forming apparatus includes a plurality of light sources, a light source control unit that controls turning on and off of the plurality of light sources, a first detection unit that detects an accumulated amount of waste toner with respect to the total capacity of the first waste toner container, and a second detection unit that detects an accumulated amount of waste toner with respect to the total capacity of the second waste toner container. The light source control unit turns on one of the plurality of light sources, based on detection results of the first detection unit and the second detection unit.

A remaining-toner-amount detecting device includes: first sensor disposed at a supply channel for a toner; a second sensor disposed at a location different from the supply channel; detection processing that compares a capacitance detected by the first sensor with a determination threshold value to detect a toner end; and a memory that stores a capacitance detected by the second sensor in an initial period as initial reference data, and a capacitance detected by the second sensor after part replacement as post-replacement reference data. The detection processing circuitry sets, based on the initial reference data, the determination threshold value as an initial determination threshold value in the initial period, and re-sets the determination threshold value, from the initial determination threshold value, to a value based on the post-replacement reference data, as a post-replacement reference data after the part replacement.