Hitachi, Ltd.

Ricoh Company, Ltd.

Ricoh Printing Systems, Ltd.

Hitachi Prinitng Solutions, Inc.

Masashi Yamamoto

Toru Miyasaka

Masahiko Saito

Kazuhiro Wakamatsu

Akira Sasaki

Akira Shimada

Nobuyoshi Hoshi

Seiji Maruo

Masanari Fujita

Yasuo Takuma

Masaru Nakano

Kenji Mori

Shigeru Kobayashi

Hiroyuki Tadokoro

Shunichi Oohara

Kazuo Kikuchi

Susumu Tsuzuku

Atsushi Onose

Eisuke Nishitani

Hideaki Shimamura

Sunao Matsubara

Akira Okamoto

Yuji Yoneoka

Masahiro Nakano

Satosi Kisimoto

Hiroyuki Shida

Koichi Niwa

Yukio Tanigaki

Tokio Kato

Motoyuki Suzuki

Tomoya Adachi

Haruyuki Honda

Isamu Terashima

Yoshitaro Ishii

Chikara Hiraoka

Tomohiko Fujii

Katsumi Kumada

Shogo Matsumoto

Nobuaki Fukasawa

Seiji Okunomiya

Tetsuro Akasaki

Tetsuo Ishikawa

Satoshi Narita

Hisao Suka

Yoshio Ohuchi

Junichi Shoji

Tetsunori Kaneko

Shizuo Tsuruta

Toshiya Sato

Hideyuki Haragakiuchi

Yuuichi Takano

Shinichi Hosaka

Jin Sawahata

Kazuhiro Wakamatus

Toru Erudemu Otsuka Room 107 Miyasaka

An image forming apparatus includes a transfer material transportation device to transport a transfer material; a transfer device to transfer a toner image to the transfer material transported by the transfer material transportation device; a fusing device, disposed after the transfer device, to fuse a toner image on the transfer material transported by the transfer material transportation device; a registration device, disposed before the transfer device, to feed the transfer material, supplied from a sheet feeder, to the transfer device; and a biasing device, disposed for the registration device, to regulate movement of the registration device to decrease a speed difference between a transfer material transport speed generated by the transfer device and a transfer material transport speed generated by the registration device.

Image forming apparatus which decreases a sheet transportation speed difference between a registration device and a transfer device

A multicolor image forming apparatus includes: a photosensitive belt unit comprising; a driving roller; a driven roller; a photosensitive belt having a joint, and a charger charging a surface of the photosensitive belt; an exposure device forming an electrostatic latent image, based on image information of each color, on the photosensitive belt; a plurality of developing devices storing different color developers, and an intermediate transfer unit performing a first transfer by sequentially superimposing each color developer image formed on the photosensitive belt. The photosensitive belt is suspended around the driving roller and the driven roller and is rotated and driven by the driving roller. Each developing device contacts and retracts from the photosensitive belt so as to develop the electrostatic latent image into a visible image using each color developer. At least one developing device can retract from the photosensitive belt at a region other than an image region.

Multicolor image forming apparatus

An image-forming device including a plurality of supporting rollers, a photosensitive belt, a pressing roller, an intermediate roller, and a charging roller. The plurality of supporting rollers includes a preselected supporting roller. The photosensitive belt is circularly movably supported on the plurality of supporting rollers. The pressing roller is disposed to contact the photosensitive belt and to press the preselected supporting roller through the photosensitive belt. The intermediate roller is disposed away from the photosensitive belt and to contact the pressing roller. The intermediate roller is rotatable following rotation of the pressing roller. The charging roller is disposed to contact both the photosensitive belt and the intermediate roller and to press the preselected supporting roller through the photosensitive belt. The charging roller is rotatable following rotation of the intermediate roller to thereby charge the photosensitive belt.

Image-forming device comprising a contact charging unit

An image forming apparatus includes a photosensitive member being movable in a predetermined direction; a charging roller that charges a surface of the photosensitive member; and a static pre-eliminator that eliminates static electricity by irradiating the surface of the photosensitive member with light, the static pre-eliminator located on an upstream side of the charging roller in a direction of movement of the photosensitive member; wherein an arrangement and an exposure amount of the static pre-eliminator are set to satisfy E &#x2266;0.025&#xd7;exp(t/&#x3c4;) where &#x3c4;is a residual time constant of a photo carrier generated in the photosensitive member by the static pre-eliminator, t is a time period from a time when the photosensitive member passes through the static pre-eliminator to a time when the photosensitive member is charged by the charging roller, and E is a normalized exposure amount of the static pre-eliminator.

Image forming apparatus including static pre-eliminator

A metal holder has a V-shape in cross-section formed by two arm sections. PET sheets are attached to mutually opposed surfaces of respective arm sections, and part of each PET sheet extends toward the electrically-conductive roller beyond the arm section. Flocked sheets are attached to the surfaces of the respective PET sheets opposite the electrically-conductive roller, and contact the electrically-conductive roller.

Image forming apparatus

An image information changing part is added to correct image information of respective colors to be recorded according to information of errors among images to be combined so that color images may be combined exactly. An image recording method and an image recording apparatus having a high-speed, high-resolution and highly stable image combining method can be obtained.

Image recording method and image recording apparatus

An image forming apparatus includes a photosensitive belt carried by a driver device, for forming a toner image thereon; an internal transcription belt for transcribing the toner image; and a transcription portion for transcribing the toner image, which is transcribed on the internal transcription belt, onto a recording medium. A transcription side roller is suspended with the internal transcription belt thereon, and disposed on a side of a photosensitive belt side roller. Detectors detect a first cycle of the internal transcription belt, and a second cycle, which starts measurement delaying by &#xbd; cycle of the photosensitive belt side roller from the first cycle measurement start. A controller conducts speed compensation of the photosensitive belt by referring to the first cycle and the second cycle, wherein the internal transcription belt is in contact with the photosensitive belt, so that it is carried following thereafter.

Image forming apparatus for conducting speed compensation by internal transcription belt cycle measurement

An electro-photographic apparatus includes a photosensitive body in the form of a photosensitive belt disposed for movement along a path in which a major portion of the path extends in a substantially vertical direction, and a plurality of developing units arranged in a vertical stack along one side of the substantially vertical path of the photosensitive body. A transfer unit is disposed adjacent to another side of the substantially vertical path of the photosensitive body, a fixing unit and a paper cassette are provided. A first transporting path is provided along which the print medium is transported in a substantially vertical direction from the paper cassette to the fixing unit via the transfer unit.

Small-size color electro-photographic apparatus

A picture image forming apparatus including a photoreceptor belt driven by a drive device, a plurality of developing devices for forming toner picture images on the photoreceptor belt, an intermediate transfer device, to a surface of which toner picture images on the photoreceptor belt are overlappingly transferred plural times when a picture image is to be formed on a single page, and a transfer roller for pushing a sheet against the intermediate transfer device in order to transfer toner picture images to the sheet. The intermediate transfer device is an intermediate transfer belt contacted by the photoreceptor belt to be driven thereby. A photoreceptor-side roller enables contact of the intermediate transfer belt and the photoreceptor belt, and the intermediate transfer belt is trained around the photoreceptor-side roller and a transfer-side roller for pushing the sheet against the transfer roller. A diameter d2 of the transfer-side roller is smaller than a diameter d1 of the photoreceptor-side roller.

Picture image forming apparatus with intermediate transfer belt trained around two rollers of different diameter

An image forming system including multiple photoconductors arranged in a line extending in a vertical direction and forming one body as one unit, and multiple development devices and multiple exposure devices arranged on one side of the line of the multiple photoconductors. An image is transferred to a recording medium on an other side of the line of the multiple photoconductors.

Photoconductor unit and image forming system

An electrophotographic image forming system having a form cassette for storing forms, a transfer unit for forming an image, a feeder for feeding the forms to the transfer unit and a fusing device for fusing transferred image of the form. The electrophotographic image forming system provides in a path for feeding the form with unfused colored particles (toner) deposited thereon, a form guide so as to contact the non-printing area of the surface of the form with unfused colored particles (toner) deposited thereon.

Electrophotographic image forming system

An electro-photographic apparatus having a photosensitive body, a plurality of developing units for forming a toner image on a surface of the photosensitive body by attaching toner on a surface of the photosensitive body, a member for receiving a print medium, a first transporting path including a printing portion for transferring one toner image in a substantially vertical direction from the photosensitive body onto one side of the print medium and a fixing portion for fixing the transferred image so as to have a printed print medium and a second transporting path disposed substantially in parallel to and coupled to the first transporting path for returning the printed print medium to the first transporting path for enabling transfer of another toner image on an opposite side on the printed print medium. The printed print medium is transported along the first transporting path for fixing the transferred image on the opposite side of the printed print medium by the fixing portion. The developing units are vertically stacked.

An intermediate transfer element has at least one or more elastic layers and a toner releasing layer provided on the surface of the elastic layer and has a surface shape including minute projections up to 60 &mgr;m and at least 20 &mgr;m high. By providing the intermediate transfer element with such projections, easy separation with respect to a poorly separable recording medium, such as thin paper is achieved, and an image free from image defects, such as white speckles.

Electrophotographic image forming device having projections on a surface of an intermediate transfer body

An image forming system having multiple photoconductors arranged in a line and forming one body as one unit, multiple development devices and multiple exposure devices arranged on one side of the line of the multiple photoconductors, an intermediate transfer device arranged on the other side of the line of the multiple photoconductors and a form cassette arranged below the line of the multiple photoconductors. The image forming system further includes a transfer device and a fusing device arranged at an opposite side of the intermediate transfer device with respect to the line of the multiple photoconductors.

In order to provide an image forming system characterized by compact configuration, high speed printing, high picture quality recording and excellent maintainability without image misregistration, an image forming system is provided, wherein multiple photoconductors are arranged along one of the surfaces of the intermediate transfer belt which is elongated in the longitudinal direction, and a fusing device is located on the other surface, with the photoconductors being integrated in one unit.

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Hitachi, Japan

Masashi Yamamoto