Fujitsu Corporation

Sachio Sasaki

Akira Nagahara

Takefumi Takahashi

Shigenobu Utaka

Mitsuru Sato

Kunihiko Sato

Masatoshi Kimura

Masahiro Wanou

Nobuo Kuwabara

Masao Konishi

Yoshio Yamaguchi

Haruyasu Watanabe

Mitsuhito Furukawa

Shin Araki

Toshio Tooda

Hideaki Iwasaki

Norio Sawatari

Hiroshi Nou

Jun Kodama

Tsuneo Watanuki

Tomohisa Mikami

Makoto Kato

Yasushige Nakamura

Shuji Koike

Toshiaki Narusawa

Satoshi Takezawa

Kenji Fuke

Nobuyuki Tanaka

Motomichi Shibano

Naoyuki Fujimoto

Junzo Nakajima

Hiroshi Kera

Hisashi Hanzawa

Mikio Amaya

Yoshiya Ishiyama

Akiyoshi Iwamasa

Futoshi Okabayashi

Takamasa Araki

Ryo Kitao

Masanori Nishido

Mituru Sato

A consumable-article detecting apparatus used to inform an operator that consumable article is unsuitable for an image forming apparatus includes a physical property detector that detects a physical property value of a consumable article used for the image forming apparatus, and a determination part that determines, based on an output from the physical property detector, whether or not the physical property value of the consumable article is within a predetermined range.

Consumable-article detecting apparatus, method and program, and image forming apparatus

A cleanerless image forming apparatus and a cleanerless image forming method facilitate the collection of residual toners after image transfer. The image forming apparatus includes a rotary endless latent carrier, a rotary charging brush for charging the rotary endless latent carrier, and a unit for forming an electrostatic latent image on the rotary endless latent carrier. The electrostatic latent image is developed on the rotary endless latent carrier by supplying polymerization toners simultaneously with the cleaning of residual polymerization toners therefrom. The polymerization toners on the rotary endless latent carrier are then transferred to a sheet. The image forming method has a first operation of charging a rotary endless latent carrier; a second operation of forming an electrostatic latent image on the rotary endless latent carrier; a third operation of developing the electrostatic latent image on the rotary endless latent carrier by supplying polymerization toners simultaneously with cleaning residual polymerization toners therefrom; and a fourth operation of transferring the polymerization toners on the rotary endless latent carrier to a sheet.

Cleanerless image forming method and system therefor

An image forming apparatus capable of preventing unnecessary adhesion of a developer to an uncharged region of a latent image carrier. The image forming apparatus includes an endless latent image carrier, a charging unit for charging the latent image carrier, a latent image forming unit for forming a latent image on the latent image carrier charged, a developing unit for developing the latent image formed on the latent image carrier with a developer by supplying the developer to the latent image carrier under application of a developing bias voltage, and a transfer unit for transferring the image developed on the latent image carrier to a sheet. The image forming apparatus further includes a driving member for rotating the latent image carrier and for driving the developing unit to supply the developer to the latent image carrier, and a controller for effecting sequence control such that the application of the developing bias voltage to the developing unit is started a predetermined time after the rotation of the latent image carrier and the drive of the developing unit and also the charging operation of the charging unit have been started. Alternatively, a driving member for driving the developing unit is provided separately, and the controller effects sequence control such that the drive of the developing unit and the application of the developing bias voltage to the developing unit are started a predetermined time after the rotation of the latent image carrier and the charging operation of the charging unit have been started.

Image forming apparatus capable of preventing adhesion of a developer to

A developing device develops a latent image formed on a latent image holding body. The developing device includes a developing roller conveying, with rotation of the developing roller, developer adhered thereto to a developing area in which the latent image on the latent image holding body should be developed, the developer including toner and carriers, a limit member, provided so as to face the developing roller, limiting a height of a layer of the developer on the developing roller, a toner container storing the toner, a toner supply mechanism supplying the toner in the toner container to the developing roller, and a partition member forming a space between the partition member and the developing roller, the toner supplied from the toner container being moved in the space with rotation of the developing roller. The developing device further includes a developer leveling member provided on an upstream side of the space in a rotation direction of the developing roller, the developer leveling member leveling the developer, formed on the developing roller, which developer has passed through the developing area.

Developing device including developer leveling member

An electrophotographic image forming apparatus including a toner circulating mechanism for recovering a residual toner scraped from a photosensitive drum to a developing device. The developing device includes a housing for defining a toner chamber, a developing roller rotatably mounted in the housing, an agitator rotatably mounted in the housing and provided in the toner chamber, and a partition member mounted to the housing to define a carrier chamber between the partition member and the developing roller. The toner circulating mechanism directly returns the residual toner scraped from the photosensitive drum to the toner chamber in the developing device. The toner chamber may contain a foreign matter removing device. The partition member may have various shapes.

Electrophotographic image forming apparatus having a device for

A developing apparatus is provided for developing an electrostatic latent image on a latent image carrier by supplying the latent image carrier with a developer. This developing apparatus includes a toner accommodating chamber for accommodating magnetic toners. The apparatus also includes a developing roller, having a plurality of fixed magnetic pole members and sleeves provided along peripheries of the fixed magnetic pole members and rotating thereabout, for feeding the developer composed of magnetic carriers and magnetic toners to the latent image carrier. The apparatus further includes a developing chamber having a partition wall formed along the developing roller and assuming a configuration adapted to a shape of the developing roller, and a toner supply port for supplying the magnetic toners to the developing chamber from the toner accommodating chamber. In another mode of the developing apparatus, the center of each magnetic pole of the fixed magnetic pole members is located in a position deviating from the toner supply port. Further, in still another mode of the developing apparatus, there is employed the magnetic carrier the core of which is iron powder exhibiting strong saturation magnetization.

Developing unit having improved toner density control

An image forming apparatus which collects residual toners on a latent image carrier in a developing unit. The image forming apparatus have a rotary endless latent image carrier; an image forming unit for forming an electrostatic latent image on the latent image carrier; a developing unit for developing the electrostatic latent image on the latent image carrier with a powdery developer and collecting residual toners on the latent image carrier at a same time; a transfer unit for transferring the developed image on the latent image carrier onto a sheet; a distribution member for distributing residual toners on the latent image carrier when in contact with the latent image carrier after image transfer; and a voltage supplying unit for supplying an AC voltage to the distribution member. An image forming apparatus according to another aspect have a rotary endless latent image carrier; an image forming unit for forming an electrostatic latent image on the latent image carrier; a developing unit for developing the electrostatic latent image on the latent image carrier with a powdery developer and collecting residual toners on the latent image carrier at a same time; a transfer unit for transferring the developed image on the latent image carrier onto a sheet; and a distribution roller for distributing residual toners on the latent image carrier when in contact with the latent image carrier after image transfer.

Image forming apparatus for collecting residual toner from a drum using

An image forming apparatus performs an electrophotographic process including a uniform charging step, an exposure step, a developing step and a transfer step on a photosensitive drum which is driven so that an image is formed on a recording medium. The image forming apparatus includes a discharging unit for discharging the photosensitive drum which has been uniformly charged, a discharging control unit for controlling said discharging unit before the photosensitive drum is stopped so that a potential distribution is obtained in an area having a predetermined width starting from a position at which said discharging unit starts to discharge said photosensitive drum, the potential distribution being between a first potential obtained by charging said photosensitive drum and a second potential, a stop control unit for performing an operation for stopping driving said photosensitive drum in a state where a developing position enters the area having the potential distribution, and a bias control unit for turning off a developing bias used in the developing step in the state where the developing position enters the area having the potential distribution.

Image forming apparatus for forming images in accordance with an

An image forming apparatus for forming an image on a sheet, including a rotary endless latent image carrier, an image forming device for forming an electrostatic latent image on a latent image carrier, a developing device for developing the electrostatic latent image on the latent image carrier with powdery developers and collecting residual toners on the latent image carrier at the same time, a transfer device for transferring a developed image on the latent image carrier onto a sheet, a distribution roller having independent foam perforations for distributing residual toners on the latent image carrier when in contact with the latent image carrier after image transfer, and a power supply for supplying an AC voltage to the distribution member. The distribution member is made of a conductive foam member having a pore at a surface contacting with the latent image carrier and the roller rotates in a direction opposite to a rotational direction of the latent image carrier at a peripheral velocity of 1.1 to 1.5 times that of the latent image carrier.

An imaging device for use in an electrographic imaging process, without a cleaning unit for residual toners, which comprises an image-carrying element, an image exposure means, a developing means, an image transfer means, and a distribution roller means of an elastic and electrically conductive material for uniformly distributing the residual toners over a surface of the image-carrying element and at the same time deelectrifying and recharging the same surface of said element. The imaging device has a simplified and compact structure and does not cause an environmental pollution problem due to the generation of ozone in the device.

Cleanerless electrographic imaging device

Developing device using two-component developer

Disclosed is an image forming apparatus capable of performing an image forming operation in both a horizontal position and an upright position. This image forming apparatus comprises a rotary endless latent image carrier; image forming unit for forming an electrostatic latent image on the latent image carrier; developing unit for developing the electrostatic latent image on the latent image carrier with a powdery developer, the developing unit having a developing room, developing rollers provided in the developing room for supplying the powdery developer to the latent image carrier, a toner supply room for supplying toners, toner supply roller provided in the toner supply room and rotatable to supply the toners to the developing room, and a partition member for partitioning the developing room and the toner supply room and forming a toner supply passage for supplying the toners to the developing room; and transfer unit for transferring the developed image on the latent image carrier to a sheet.

Image forming apparatus having a developing apparatus which includes a

An electrostatic latent image is developed on a latent image carrier and residual toners are collected at the same time. An electrostatic latent image is formed on a rotary endless latent image carrier; developer, including magnetic toners and magnetic carriers, is supplied to a developing area for developing the latent image carrier, and a magnetic brush is formed with the developer in the developing area to thereby collect residual toners on the latent image carrier and develop the electrostatic latent image on the latent image carrier; and the developed image on the latent image carrier is transferred to a sheet. An electrostatic latent image may be developed with a rotary endless latent image carrier; an image forming unit for forming an electrostatic latent image on the latent image carrier; a developing unit having a developer, including magnetic toners and magnetic carriers, and a developer supplying unit for supplying the developer to a developing area for developing the latent image carrier and forming a magnetic brush with the developer in the developing area in order to develop the electrostatic latent image on the latent image carrier with a powdery developer and collect residual toners on the latent image carrier; and a transfer unit for transferring the developed image on the latent image carrier to a sheet.

Image forming method and apparatus with magnetic brush

Disclosed is an image forming apparatus capable of performing an image forming operation in both a horizontal position and an upright position. This image forming apparatus comprises a rotary endless latent image carrier; image forming unit for forming an electrostatic latent image on the latent image carrier; developing unit for developing the electrostatic latent image on the latent image carrier with a powdery developer, the developing unit having a developing room, a developing roller provided in the developing room for supplying the powdery developer to the latent image carrier, a toner supply room for supplying toners, toner supply roller provided in the toner supply room and rotatable to supply the toners to the developing room, and a partition member for partitioning the developing room and the toner supply room and forming a toner supply passage for supplying the toners to the developing room; and transfer unit for transferring the developed image on the latent image carrier to a sheet.

Image forming apparatus

Disclosed is a slim printing apparatus which employs a latent image forming method, such as electrophotographing method, and needs an apparatus-occupying area. This printing apparatus comprises a hopper for retaining sheets; a feeding path defined on that surface of the apparatus which is opposite to that surface of the apparatus where the hopper is disposed for conveyance of sheets; a feeding mechanism for feeding a sheet from the hopper onto the feeding path; an endless rotary latent image carrier provided between the hopper and the feeding path; an image forming unit, provided between the hopper and the feeding path, for forming a toner image on the latent image carrier; a transfer unit for transferring the toner image on the latent image carrier onto the sheet conveyed along the feeding path; and a fixing unit for fixing the toner image on the sheet.

Printing apparatus

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Kawasaki, Japan

Sachio Sasaki