Abstract: An image forming apparatus having a cleaner for cleaning a surface of a dust-proof glass disposed on a housing of a laser scanning unit for irradiating a photosensitive member with a laser modulated in accordance with image data. The cleaner is supported by a frame of the image forming apparatus body such that the cleaner is movable while keeping in contact with the dust-proof glass and such that the cleaner stays in a stand-by position while keeping out of contact with the dust-proof glass and the housing of the laser scanning unit.

Abstract: An image forming apparatus having a cleaner for cleaning a surface of a dust-proof glass disposed on a housing of a laser scanning unit for irradiating a photosensitive member with a laser modulated in accordance with image data. The cleaner is supported by a frame of the image forming apparatus body such that the cleaner is movable while keeping in contact with the dust-proof glass and such that the cleaner stays in a stand-by position while keeping out of contact with the dust-proof glass and the housing of the laser scanning unit.

Abstract: An image-writing device writes a dot image onto an image-receiving body in such a way that the dots align at a certain screen angle. The dots are written by an array of writing elements such as light-emitting diodes. The image-writing device has a memory that stores compensation parameters that compensate for non-uniformity of the writing elements. The compensation parameters are also calculated to produce dots with approximately uniform widths as viewed in the screen-angle direction. When driven according to the compensation parameters, the writing elements produce a dot image that is comparatively free of dot-width irregularities aligned in the screen-angle direction, which is the direction in which such irregularities are most noticeable.

Abstract: A toner cartridge for an image forming apparatus which can detect the remaining state of a developer even when the developer in the cartridge is biased by the rotation and stirring of a rotary conveyance body. A developer detector arranged outside the toner cartridge has a light projecting unit and a light receiving unit, and the toner cartridge has detection windows through which light projected from the light projecting unit is input and output. The optical axis of an optical path from the light projecting unit to the light receiving unit intersects the rotary shaft of the rotary conveyance body in the toner cartridge or becomes parallel to the moving direction of the developer. The remaining state of the developer is detected according to whether the optical path going from the light projecting unit to the light receiving unit is cut off or not.

Abstract: A toner cartridge for an image forming apparatus which can detect the remaining state of a developer even when the developer in the cartridge is biased by the rotation and stirring of a rotary conveyance body. A developer detector arranged outside the toner cartridge has a light projecting unit and a light receiving unit, and the toner cartridge has detection windows through which light projected from the light projecting unit is input and output. The optical axis of an optical path from the light projecting unit to the light receiving unit intersects the rotary shaft of the rotary conveyance body in the toner cartridge or becomes parallel to the moving direction of the developer. The remaining state of the developer is detected according to whether the optical path going from the light projecting unit to the light receiving unit is cut off or not.

Abstract: An electrophotographic image forming apparatus in which an electrostatic latent image is formed on a charged surface of a photoconductive drum. The image is developed with toner into a toner image and the toner image is transferred to a recording medium. A charging roller is in contact with the photoconductive drum and charges the photoconductive drum when the charging roller receives a high voltage. A detector detects a characteristic such as an electrical resistance of the charging roller and outputs a signal indicative of the characteristic. A charging power supply applies a high voltage to the charging roller, the voltage having a value in accordance with the signal. A neutralizing device neutralizes the charged surface of the photoconductive drum before the detector detects the characteristic of the charging roller but does not neutralize the charged surface of the photoconductive drum when the electrostatic latent image is being formed.

Abstract: An electrophotography apparatus has a charging unit, and an exposing unit, and a developing unit. The charging unit charges the surface of a rotating image bearing body having an axis of rotation. The exposing unit emits light to illuminate the surface of the image bearing body to form an electrostatic latent image on the surface. The developing unit applies charged toner to the electrostatic latent image to develop the electrostatic latent image into a visible image. The electrophotography apparatus includes, for example two electrodes and power supplies for applying voltages to the electrodes. The electrodes are disposed between the light-emitting surface of the exposing unit and extend parallel to the axis of rotation of the image bearing body. The electrodes are aligned on opposite sides of the light emitted from the exposing unit.

Abstract: A toner hopper which is arranged upwards of the developing unit is elevatably supported in the image forming device in the vertical direction thereof and the connection between the toner hopper and the developing unit can be cancelled by lifting up the toner hopper when drawing out the developing unit so that the structure of the connection portion therebetween can be simplified and the sliding portion can be eliminated to thereby eliminate wearing at the connection therebetween. Furthermore, an apparatus for automatically raising and lowering the toner hopper and an apparatus for maintaining the horizontality of the toner hopper when being elevated and lowered is provided.

Abstract: A toner cartridge unit for a copying machine having a double shutter at the mouth of the toner cartridge. The double shutter is locked when the cartridge is not attached to a toner hopper of the copying machine and prevents toner from coming out. Owing to the double shutter structure, the outside of the cartridge is always clean. When the cartridge unit is attached to the hopper, many locking and releasing mechanisms for the double shutter and a third shutter provided at the hopper entrance work sequentially and automatically as the cartridge is moved from a preparation site to a supplying site of the toner hopper.