Fujitsu Corporation

Hideyuki Nanba

Masato Kawashima

Mamoru Watanabe

Michihiro Fujii

Shigenori Sasaki

Koji Hirata

Nobuo Fujita

Kenji Fuke

Akihiro Komuro

Kiyoshi Nakamichi

Masanao Nagakura

Yoshihiro Hirabayashi

Hiroyuki Okitsu

Yoshito Hukata

Toshihiro Matsui

Susumu Fujishima

An image-forming apparatus for a sheet cassette that contains the sheets to be processed by hardware and is loaded in the hardware. The apparatus has a display window provided on a front panel of the sheet cassette, a sheet size display member displaying a letter indicating a sheet size, and the sheet size display member including a sheet size-definition member that enables a sheet size to be defined in the form of capable of detecting the sheet size. Whereby, the letter showing the desired sheet size can be manually indicated on the display window, and sheet size detector for detecting the sheet size-definition member of the sheet size display member, thereby detecting the sheet size indicated on the display window.

Sheet-size detection mechanism for sheet cassettes and

A toner image transferring device is used to electrostatically transfer a charged toner image from a roller to a sheet of paper. The device includes a transfer charger for giving the paper an electric charge. A charge eliminator is located next to the roller for partially eliminating the electric charge from the paper. The charge eliminator is positioned to be adjacent to the paper and the roller, but displaced from the transfer charger. Paper passes through the device such that the paper is in contact with the roller when passing over the transfer charger, thereby optimizing the transfer of the toner image from the roller to the paper.

Toner image transferring device including transfer charger and AC charge

A toner image fixing device includes a heat roller, and a backup roller engaged with the heat roller to form a nip therebetween. A paper carrying a toner image is passed through the nip whereby the toner image is thermally fused and fixed on the paper. The heat roller, which is stained by a part of the fused toner during the fixing process, should be cleaned before a toner image is fixed on a successive paper without staining. To this end, a cleaning roller made of a felt material is pressed against the heat roller so as to be rotated together with the heat roller by a frictional force acting therebetween. The cleaning roller must be periodically replaced. The fixing device is constituted such that the replacement of the cleaning roller can be easily and quickly carried out.

Heat roller type toner image fixing device having cleaning roller

The invention relates to a developer cartridge for exchanging developers in an apparatus which develops an electrostatic latent image, and an image forming apparatus using the developer cartridge. The developer cartridge has a first storage room for unused developer, a second storage room under the first room for storing used developer, openings in the first and second rooms and shutters provided therewith, together with a paddling mechanism in the first storage room for moving unused developer. The image forming apparatus has an endless latent carrier, a mechanism for forming an electrostatic latent image on the carrier and a mechanism for developing the latent image on the carrier. The developer cartridge is detachable positioned to the developing mechanism and a mechanism is provided for driving the shutters of the developer cartridge for exchanging used developer with unused developer.

Developer cartridge and image forming apparatus using the same

In an image-forming apparatus, in which an electrostatic latent image on a photoconductive drum is developed by a toner accommodated in a container, a periodical exchange of carrier in a container is necessary. A method thereof includes steps of fitting a cartridge to the container, discharging all of an old mixture of toner and carrier from the container to the lower chamber, transferring fresh carrier from the carrier compartment into the container, and further, transferring fresh toner from the toner compartment into the container until a predetermined initial color density of the mixture is obtained.

Process and apparatus for replacing the carrier portion of a developing

A paper transport mechanism includes a first guide plate having an end part, a rotation fulcrum located in a vicinity of the end part and first rollers, a second guide plate having a first surface part which confronts the first guide plate with a gap formed therebetween in a closed position of the first guide plate, a second surface part which is curved, second rollers and fourth rollers which make pressing contact with the first rollers in the closed position of the first guide plate so as to transport a paper between the first and second guide plates, a third guide plate having a third surface part which confronts the second surface part of the second guide plate with a gap formed therebetween and third rollers which make pressing contact with the second rollers in the closed position of the first guide plate so as to transport a paper between the second and third guide plates, and a mechanism for urging the third rollers against the second rollers in the closed position of the first guide plate and for separating the third rollers from the second rollers in an open position of the first guide plate.

Paper transport mechanism

Disclosed are a developer cartridge designed to ensure exchange of developers and toner supplement, and an image forming apparatus using this cartridge. This developer cartridge includes a cylindrical body whose rotational axis extends in a direction perpendicular to the developer carrying direction of the developing unit, a first developer storage room, provided at one portion of the cylindrical body, for storing an unused developer, a second developer storage room, provided at the other portion of the cylindrical body, for storing a supplemental toner, openings respectively formed in the first and second developer storage rooms of the cylindrical body, and a case with a cylinder shape for rotatably retaining the cylindrical body, the case having a pair of injection ports respectively provided in association with the opening of the first developer storage room and the opening of the second developer storage room. The image forming apparatus includes an endless latent carrier, structure for forming an electrostatic latent image on the endless latent carrier, developing mechanism for developing the electrostatic latent image on the endless latent carrier, a developer cartridge detachably attached to the developing mechanism for exchanging developers and for toner supplement, and having the same components as the above-described cartridge, and drive mechanism for driving the cylindrical body of the attached developer cartridge, for exchanging a used developer with an unused developer and for toner supplement.

Developing cartridge for copier

A paper transport mechanism which is suited for use in an image forming apparatus such as a copying machine which allows the user to more easily remove paper jammed between guide plates. The paper transport mechanism includes at least three guide plates which engage one another when the transport mechanism is in use, but may be separated, each from the other, in order to clear a jammed paper path. The first guide plate has an open and a closed position. The second and third guide plates each have rollers attached. When the paper transport mechanism is in use, the first guide plate is in the closed position and the rollers of the second and third guide plates press against one another and transport paper therebetween. When a paper jam occurs, the first guide plate is moved to the open position and the second and third guide plates and their associated rollers are separated to allow access to any paper jammed therebetween.

A two-sided printing apparatus includes a sheet feeding unit, an image printing unit, a sheet ejecting unit, and a sheet refeeding unit for refeeding a sheet having a first surface on which images have been printed to the image printing unit in order to print images on a second surface of the sheet. The sheet refeeding unit includes a base, an inclined frame rotatably fastened to the base, a first guide member facing the inclined frame, and a second guide member facing the base. The sheet moves downwards between the inclined frame and the first guide member and then moves between the base and the second guide member. The first guide member is rotatably supported so that the first guide member is raised and the inclined frame is lowered, a first space is formed between the lowered inclined frame and the raised first guide member. The second guide member is rotatably supported so that the second guide member is raised, a space is formed between the base and the second raised guide member.

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Kawasaki, Japan

Hideyuki Nanba