A toner cartridge according to one example embodiment includes a developer roll and a toner adder roll. First and second drive gears are rotatably connected to and coaxial with the developer roll and toner adder roll, respectively. The toner cartridge includes a drive coupler exposed to receive rotational motion when the toner cartridge is installed in an image forming device. Gear teeth of the first drive gear are directly meshed with gear teeth of the drive coupler of the toner cartridge. The second drive gear is rotatably connected to the drive coupler through a pair of idler gears.

An image forming apparatus includes an image carrier that carries an image to be transferred onto a recording medium, a charging member in contact with the image carrier, the charging member that charges the image carrier, an erase unit that erases charge on the image carrier, a current detector that detects a current flowing to the charging member; a forming unit that forms a charged region on a surface of the image carrier, and forms an erased region on the surface of the image carrier using the erase unit, and a state acquisition unit that acquires a deterioration state of the charging member based on (i) a first current flowing in response to applying a voltage from the charging member to the erased region and (ii) a second current flowing in response to applying a voltage from the charging member to the charged region.

A drum cartridge includes a first photosensitive drum, a frame, a main body connector, a first toner cartridge connector, a drum-cartridge circuit board, a harness, and a first harness. The harness is electrically connected between the main body connector and the drum-cartridge circuit board. The harness extends in the first direction. The first harness is electrically connected between the first toner cartridge connector and the drum-cartridge circuit board. The first harness extends in the second direction.

A drum cartridge that is mountable to and demountable from a main body of an image forming apparatus, the drum cartridge including: a photosensitive drum rotatable about a first axis extending in a first direction; and a first conveying roller rotatable about a second axis extending in the first direction, the first conveying roller being in contact with a second conveying roller of the image forming apparatus and being configured to convey a sheet, which is sandwiched between the first conveying roller and the second conveying roller, toward the photosensitive drum in a state where the drum cartridge is mounted on the main body, in which the drum cartridge has a guide groove into which an end portion of the second conveying roller in the first direction is inserted in the state where the drum cartridge is mounted on the main body.

An image forming apparatus includes an image carrier that carries an image to be transferred onto a recording medium, a charging member in contact with the image carrier, the charging member that charges the image carrier, an erase unit that erases charge on the image carrier; a current detector that detects a current flowing to the charging member; a forming unit that forms a charged region on a surface of the image carrier, and forms an erased region on the surface of the image carrier using the erase unit, and a state acquisition unit that acquires a deterioration state of the charging member based on (i) a first current flowing in response to applying a voltage from the charging member to the erased region and (ii) a second current flowing in response to applying a voltage from the charging member to the charged region.

A printing apparatus is provided. The apparatus comprises a light-emitting element, a light-receiving element including a first terminal and a second terminal, a reference current generator supplying a reference current, a comparator comparing a monitor current with the reference current, the light-receiving element supplying the monitor current to the second terminal in accordance with a light emission amount, a driver driving the light-emitting element based on an output of the comparator, and a reference voltage controller. The comparator includes a first input terminal connected to the second terminal and a second input terminal. The reference voltage controller supplies a reference voltage selected from at least two voltage values to the second input terminal, and to control the voltage of the second terminal to be a voltage according to the reference voltage.

A drum cartridge includes a first photosensitive drum, a frame, a main body connector, a first toner cartridge connector, a drum-cartridge circuit board, a harness, and a first harness. The harness is electrically connected between the main body connector and the drum-cartridge circuit board. The harness extends in the first direction. The first harness is electrically connected between the first toner cartridge connector and the drum-cartridge circuit board. The first harness extends in the second direction.

An image forming apparatus includes a rotatable photosensitive member. A charging member charges a surface of the photosensitive member. A developing roller carries developer. The developing roller supplies the developer in normal polarity to the surface of the photosensitive member. A regulating member regulates the developer on the developing roller. A common voltage applying unit applies charging voltage and regulating voltage. The regulating voltage is applied with the developing roller rotating such that a potential difference in a direction in which electrostatic force from the regulating member to the developing roller acts on the developer charged in the normal polarity, is formed between the regulating member and the developing roller, and in which the charging voltage to be applied in a non-image-forming period is controlled so as to be smaller in absolute value than in an image-forming period.

A processing device includes: a frame that supports a photosensitive drum; a bearing member that biases a charge roller in the direction to be in contact with the photosensitive drum; and a holder that is switchable between a holding state where the charge roller is separated from the photosensitive drum and a canceled state where the holding state is canceled so that the roller is brought into contact with the photosensitive drum; wherein a canceling member is provided in at least one of inside the processing-device attachment and an attachment body attached to an image forming apparatus main body at a front side to cause the holder to shift from the holding state to the canceled state. The canceling member causes the holder to shift from the holding state to the canceled state when the attachment body is attached to the image forming apparatus main body at the front side.

An electrically conductive support for use in an electrophotographic photoreceptor includes a cylindrical main body having a first end and a second end opposite to the first end in an axial direction of the main body. The main body contains an aluminum alloy and has an internal stress in a range of 30 MPa to 5 MPa. A method of producing the electrically conductive support includes preparing a substrate containing an aluminum alloy obtained at least through an extrusion step, and heat treating the substrate to obtain the electrically conductive support. The heat treating is carried out such that, when a temperature of the heat treating is defined as T ( C.) and a time of the heat treating is defined as H (hours), an amount of the heat treating Q defined by Q=TH is 800 or less.