Abstract: An abnormal sound diagnostic apparatus for an image formation device, which includes: a specification section that specifies an independently operable drive section; an operation section that selectively operates the drive section specified by the specification section; a receiving section that receives an abnormal sound confirmation input which is inputted in a case where an abnormal sound occurs by operating the drive section through the operation section; and an identifying section that, on the basis of the abnormal sound confirmation input received by the receiving section, identifies the drive section specified by the specification section as an abnormal sound occurring location.

Abstract: A developer cartridge for supplying a toner-containing developer, including a developer containing portion; a developer recovery portion, disposed at one end of the developer containing portion in a longitudinal direction; a supply port that supplies the developer from the developer containing portion to the developing unit; a recovery port through which used developer supplied from the developing unit passes to the developer recovery portion; and an opening and closing member, coupled to the outer circumferential of the developer containing portion and the developer recovery portion, that opens or closes the supply port and the recovery port. The developer containing portion has first and second end portions, the first end portion being more slender than the second end portion and linked to the developer recovery portion, wherein a tapered portion is provided between the first end portion and the second end portion.

Abstract: An abnormal sound diagnostic apparatus for an image formation device, which includes: a specification section that specifies an independently operable drive section; an operation section that selectively operates the drive section specified by the specification section; a receiving section that receives an abnormal sound confirmation input which is inputted in a case where an abnormal sound occurs by operating the drive section through the operation section; and an identifying section that, on the basis of the abnormal sound confirmation input received by the receiving section, identifies the drive section specified by the specification section as an abnormal sound occurring location.

Abstract: An image forming apparatus includes a rotary developing device having a developing device main body rotatably disposed and a plurality of developing units arranged along a rotation direction of the developing device main body, a frame for supporting the rotary developing device in free rotation, and a drive source for rotationally driving the rotary developing device, characterized in that the drive source for rotationally driving the rotary developing device is disposed in an area to which the rotary developing device is projected in a direction orthogonal to a rotation axis.

Abstract: An image forming apparatus includes a rotary developing device having a developing device main body rotatably disposed and a plurality of developing units arranged along a rotation direction of the developing device main body, a frame for supporting the rotary developing device in free rotation, and a drive source for rotationally driving the rotary developing device, characterized in that the drive source for rotationally driving the rotary developing device is disposed in an area to which the rotary developing device is projected in a direction orthogonal to a rotation axis.

Abstract: An image forming apparatus includes a rotary developing device having a developing device main body rotatably disposed and a plurality of developing units arranged along a rotation direction of the developing device main body, a frame for supporting the rotary developing device in free rotation, and a drive source for rotationally driving the rotary developing device, characterized in that the drive source for rotationally driving the rotary developing device is disposed in an area to which the rotary developing device is projected in a direction orthogonal to a rotation axis.

Abstract: An image forming system adopting a dual-component developing system-for forming on an image carrier a toner image. The image forming system includes a charge unit for uniformly charging a surface of the image carrier, a developing magnet roll for giving a bias potential to toner, a switching device, such as a bipolar transistor, connected to a PWM image signal, a charge accumulating device, connected to the switching device, for accumulating charges, a total charge amount detection circuit for determining the total amount of charges, and a prediction device for predicting the total consumption of toner depending on the total amount of determined charges.

Abstract: An image forming system adopting a dual-component inversion developing system for forming on an image carrier a toner patch image used for detecting an image concentration and controlling an image forming condition such as toner concentration based on the concentration of the toner patch image. The image forming system includes a charge unit for uniformly charging a surface of the image carrier, a developing magnet roll supplied with a developing bias, and a patch forming unit for selecting voltage application conditions to the charge unit and the developing magnet roll so as to reverse the bias potential relationship between the developing magnet roll and a charge potential of the image carrier and forming a first toner patch image at a contrast potential between the charge potential of the image carrier and the bias potential.