Fujitsu Corporation

Toshimasa Toyama

Kiyoshi Chinzei

Naoto Hirao

Yoshihiro Tonomoto

Masaaki Ohyama

Toshio Hino

Katsumi Adachi

Katsuya Shimatsu

Yasuharu Takeuchi

Makoto Maki

Mituaki Ono

Takashi Suzuki

Tsutomu Nagatomi

Yoshinori Wada

Seiji Suketomo

Hiroaki Naito

Jun Shimizu

Osamu Watanabe

Akihiko Uematsu

Yuzuru Sugiura

Miki Yamamoto

An electrophotographic printer includes a photosensitive drum, a developing unit, an image transfer unit, and pre-transfer discharges arranged between the developing unit and the image transfer unit. The pre-transfer discharging means is arranged to progressively reduce the absolute value of the electric potential of a given point in the surface of the photosensitive drum. The reduction of the electric potential is performed in a non-abrupt manner through two or more steps as the given point is moved from the developing unit to the image transfer unit.

Electrophotographic image-forming apparatus having a static eliminator

The invention provides a continuous medium printing apparatus which can exert a transporting force to act upon a continuous medium without additional provision of a new tractor mechanism or some other transport mechanism. In the continuous medium printing apparatus, upon automatic loading of a continuous medium, a control section controls a charging operation of a charging section so that a leading end portion of the continuous medium may be electrostatically attracted to an image forming drum. The image forming drum to which the continuous medium is attracted is rotated in a printing transporting direction to exert a transporting force to act upon the continuous medium to transport the continuous medium in the printing transporting direction. The present invention is applicable to an apparatus which prints on a continuous medium such as continuous recording paper (continuous paper), for example, by electrophotography.

Continuous medium printing apparatus

A developing apparatus of an electrophotographic apparatus includes a housing for accommodating a developer, first, second and third developing rollers are rotatably disposed in the housing and arranged opposite to a photoconductor drum for conveying a developer carried on respective surfaces of the developing rollers, and a conveyor roller rotatably disposed in the housing for conveying the developer carried on a surface thereof to one of the developing rollers. First and second screw conveyors are disposed in the housing for conveying the developer in an axial direction opposite to each other. Each of these conveyors has an axial length larger than an axial length of the developing rollers. A partition wall is disposed between the first and second screw conveyors. A toner container for accommodating a toner is mounted on the housing. The toner in the toner container is supplied into the housing and agitators agitate the toner in the housing. A first doctor blade regulates the developer carried on the conveyor roller, a second doctor blade regulates the developer on the first developing roller, and scrapers scrape the developer from the second and third developing rollers.

Electrophotographic image-forming apparatus having developing device

An intermittent ejection processing unit detects a driving state of at least one of driving motors of a developing agent conveying member and a stirring member which are driven at a predetermined rotational speed when a developing agent is ejected and intermittently makes each driving motor operative until a detection value of the driving state decreases to a specified value, thereby intermittently ejecting the developing agent. A continuous ejection processing unit continuously makes each driving motor operative at a predetermined rotational speed after the detection value of the driving state of at least one of the driving motors was below the specified value, thereby continuously ejecting the developing agent, and finishes the ejection of the developing agent when the detection value of the motor driving state decreases to a specified value corresponding to a no-load state by the completion of the ejection of the developing agent.

Electrophotographing apparatus and developing agent ejecting method

An image forming apparatus includes a plurality of process units contacting a continuous recording medium and transferring images on the recording medium, a separating and contacting mechanism for controlling at least one of the recording medium and each of the process units to a separated state where the recording medium and the process unit are separated from each other and a contacting state where the recording medium and the process unit contact each other, and a controller for controlling the separating and contacting mechanism at a position where the process unit confronts a non-printing region on the recording medium so as to put the recording medium and the process unit to the contacting state.

Image forming apparatus

An image forming apparatus includes a fixing unit including at least a pair of rollers which thermally fix a toner image formed on a surface of a recording medium by pressing against the recording medium, and a separating and contacting mechanism supporting the pair of rollers so that the rollers can separate from and make contact with the recording medium, where the separating and contacting mechanism controls the rollers when contacting the rollers to the recording medium, by contacting each of the rollers approximately perpendicularly to the surface of the recording medium and so that the recording medium thereafter makes contact with a surface of each of the rollers for a wrap-around angle greater than 0.degree..

The present invention relates to a developing device which is arranged in an image forming device such as an electronic photo printer and an electrostatic recording-type printer and which develops developer on an electrostatic latent carrier transferring an electrostatic latent image and to an electrostatic recording device including the developing device. The object is to provide a device with high reliability which can decrease developer dispersion and the frequency of maintenance. The developing device consists of a developing roller for conveying a two-component developer by creating a magnetic brush to an electrostatic latent image carrier on which a latent image is formed and for moving in a direction opposite to the moving direction of the electrostatic latent carrier in a developing area to an electrostatic latent image carrier; a developer regulating plate for regulating the amount of the two-component developer to the developing roller; and a dispersion blocking plate protruding toward the developing area from the developer regulating plate.

Developing device having a dispersion blocking plate and electrostatic

An image forming apparatus is provided which ensures proper image forming when the apparatus is positioned either horizontally or upright. The apparatus includes a rotary, endless latent image carrier, and a latent image forming arrangement for forming a latent image on the latent image carrier. The apparatus also includes a developing arrangement for developing the latent image on the latent image carrier by using powdered developer, and a transferring arrangement for transferring a developed image on the latent image carrier to a sheet. The apparatus further includes a positioning mechanism for selectively positioning the developing arrangement relative to the latent image carrier at one of a first position corresponding to an upright installation of the apparatus and a second position corresponding to a horizontal installation of the apparatus.

Growing community of inventors

Kawasaki, Japan

Toshimasa Toyama