Abstract: A developer supplying device includes an inflow path; a guide path having an inlet to which a lower end of the inflow path is connected, the guide path extending diagonally downward from the inlet, the guide path guiding the developer to a developing unit; and a transport unit disposed in the guide path, the transport unit including a helical screw blade and a holder that holds the helical screw blade, the transport unit transporting the developer to the developing unit by rotating. In at least a part of a region in the guide path facing the inlet, a pitch of the helical screw blade in a horizontal direction is greater than or equal to a width of the inlet, and the holder is located at a position displaced from the rotation axis of the transport unit.

Abstract: A developer supplying device includes an inflow path; a guide path having an inlet to which a lower end of the inflow path is connected, the guide path extending diagonally downward from the inlet, the guide path guiding the developer to a developing unit; and a transport unit disposed in the guide path, the transport unit including a helical screw blade and a holder that holds the helical screw blade, the transport unit transporting the developer to the developing unit by rotating. In at least a part of a region in the guide path facing the inlet, a pitch of the helical screw blade in a horizontal direction is greater than or equal to a width of the inlet, and the holder is located at a position displaced from the rotation axis of the transport unit.

Abstract: A developing device includes a housing accommodating a developer containing a toner and a magnetic carrier; first and second developing members facing an image bearing member and having substantially-cylindrical first and second rotatable sleeves and first and second magnet rollers supported therein and having magnetic poles; a supply member supplying the developer onto the first sleeve; a layer regulating member facing the first sleeve and regulating a layer of the developer; and an electrode member facing the second sleeve with a distance therebetween and disposed upstream, in the second-sleeve rotational direction, of where the second sleeve receives the developer from the first sleeve and downstream of where the second developing member faces the image bearing member. An electric field removing the toner from the second sleeve or causing the toner on the carrier to adhere onto the second sleeve is generated between the electrode member and the second sleeve.

Abstract: A first image forming unit includes a first developing unit that develops a latent image, and a second image forming unit includes a second developing unit that develops a latent image. A transfer unit transfers an image formed by at least one of the first and second image forming units onto a recording medium. A controller performs control to form a transfer image on the recording medium through at least one of a first operation and a second operation. In the first operation, images formed by the first and second image forming units are transferred onto the recording medium as transfer images. In the second operation, the image formed by the first image forming unit is transferred onto the recording medium as a transfer image. A stopping unit stops operation of the second developing unit when the number of transfer images formed through the second operation reaches a preset value.

Abstract: A first image forming unit includes a first developing unit that develops a latent image, and a second image forming unit includes a second developing unit that develops a latent image. A transfer unit transfers an image formed by at least one of the first and second image forming units onto a recording medium. A controller performs control to form a transfer image on the recording medium through at least one of a first operation and a second operation. In the first operation, images formed by the first and second image forming units are transferred onto the recording medium as transfer images. In the second operation, the image formed by the first image forming unit is transferred onto the recording medium as a transfer image. A stopping unit stops operation of the second developing unit when the number of transfer images formed through the second operation reaches a preset value.

Abstract: An image forming apparatus includes plural toner image forming devices. Each of which has a rotating photoconductor, a charging device that uniformly charges a surface of the photoconductor, a latent image forming device that forms an electrostatic latent image on the surface of the charged photoconductor, a developing device that develops the electrostatic latent image on the surface of the photoconductor to a toner image, and a developing container that contains toner used by the developing device. A diameter of the photoconductor of at least one toner image forming device is formed larger than a diameter of the photoconductor of the other toner image forming devices. Each developing container of all the toner image forming devices is formed in equal-sized, and a center of rotation of a developing roll of each developing device is arranged in a position upper than a center of rotation of each photoconductor.

Abstract: An image forming apparatus includes plural toner image forming devices. Each of which has a rotating photoconductor, a charging device that uniformly charges a surface of the photoconductor, a latent image forming device that forms an electrostatic latent image on the surface of the charged photoconductor, a developing device that develops the electrostatic latent image on the surface of the photoconductor to a toner image, and a developing container that contains toner used by the developing device. A diameter of the photoconductor of at least one toner image forming device is formed larger than a diameter of the photoconductor of the other toner image forming devices. Each developing container of all the toner image forming devices is formed in equal-sized, and a center of rotation of a developing roll of each developing device is arranged in a position upper than a center of rotation of each photoconductor.

Abstract: An image formation apparatus includes a developing unit for developing latent image, and a reserve tank that temporarily stores developer ejected from a first cartridge and a second cartridge and that discharges the developer to the developing unit. The reserve tank is provided with a storage amount sensor for sensing storage amount of the developer in the first reserve tank. The image formation apparatus further includes a controller for controlling ejection of developer from at least the first cartridge and the second cartridge into the first reserve tank in accordance with output from the storage amount sensor.

Abstract: An image formation apparatus includes a developing unit for developing latent image, and a reserve tank that temporarily stores developer ejected from a first cartridge and a second cartridge and that discharges the developer to the developing unit. The reserve tank is provided with a storage amount sensor for sensing storage amount of the developer in the first reserve tank. The image formation apparatus further includes a controller for controlling ejection of developer from at least the first cartridge and the second cartridge into the first reserve tank in accordance with output from the storage amount sensor.