Ricoh Printing Systems, Ltd.

Other

Hitachi, Ltd.

Ricoh Company, Ltd.

Hitachi Printing Solutions, Ltd.

Kenji Asuwa

Masahiro Yagi

Shintaro Yamada

Toru Miyasaka

Kazutaka Sato

Taichiro Yamashita

Isao Nakajima

Shigeru Obata

Yukio Otome

Toshio Ogiso

Hiroaki Ikeda

Tatsuya Miyadera

Tomofumi Yoshida

Hirobumi Ooyoshi

Susumu Tateyama

Ryuji Inoue

Hirokazu Iwata

Hiroyuki Mabuchi

Shuho Yokokawa

Chikara Hiraoka

Shunichi Oohara

Izumi Kinoshita

Yoshiko Ogawa

Yasuo Matsuyama

Akitomo Kuwabara

Akihiko Yamazaki

Tatsuya Ozaki

Shin Murayama

Shuuichi Nakagawa

Toru Hanashima

Tomio Sugaya

Tetsuji Takegoshi

Yasushi Kinoshita

Rumi Konishi

Kazushige Oonishi

Tetsuya Ooba

Satoshi Shirasawa

Hui Cheng

Shunjchi Oohara

A positional error detection method forms, on a belt which is transported in a transport direction, positional error detection marks for detecting a positional error between image positions of first and second colors, detects the positional error detection marks on the belt, and computes the positional error based on the detected positional error detection marks. The positional error detection marks include first and second marks which are inclined in mutually opposite directions with respect to the transport direction, and third marks which are perpendicular to the transport direction.

Positional error detection method and apparatus, and computer-readable storage medium

A disclosed developing device includes a developing roller; a supply roller that is in contact with the developing roller and configured to supply toner to the developing roller; a current measuring unit configured to measure an electric current that flows from the developing roller to the supply roller when the toner is supplied from the supply roller to the developing roller; and an error determining unit configured to detect a development error of the developing roller based on the electric current measured by the current measuring unit.

Developing device, image forming apparatus, and development error detecting method

Provided is a small-sized electrophotographic apparatus for which maintenance such as disposal of a jam of sheets, replacement of consumables including toner, or replacement of components to be periodically replaced can be facilitated. Thus, there is provided a tandem type electrophotographic apparatus using an intermediate transfer belt, in which photosensitive drums are arranged in a vertical one row, the intermediate transfer belt is located on one side of the row of the photosensitive drums, the developing means are located on the other side of the row of the photosensitive drums, a transfer means for transfer a toner image from the intermediate transfer belt onto a recording medium is located above the row of the photosensitive drums, a recording medium conveying path composed of a vertical conveying path (a front opening door) for conveying a recording medium fed from the recording medium supply means, outside of the developing means and substantially in parallel with the intermediate transfer belt, a curved part and a horizontal conveying path for conveying the recording medium up to a transfer means in a substantially horizontal direction, and a fixing means for fixing a toner image transferred onto the recording medium is incorporated in the horizontal conveying path (a top surface opening door), downstream of the transfer means.

Electrophotograhic apparatus

An image forming apparatus comprising: an image forming section and a residual toner amount detection unit. The image forming section includes a photosensitive member, a charging unit, an exposure unit, a developing unit, and a toner storage unit. The residual toner amount detection unit detects an amount of toner remaining in the developing unit. The residual toner amount detection unit includes a light-emitting element and a light-receiving element. After the toner is deposited on the photosensitive member to form a toner image until electric charge is given onto a photosensitive layer of the photosensitive member by the charging unit again, the light-emitting element removes electric charge remaining on the photosensitive layer.

Image forming apparatus and image forming unit

An electrophotographic apparatus includes a plurality of image forming devices, wherein each image forming device includes a developing device having a tip end part and a toner storage part coupled to the tip end part. A thickness of the tip end part is smaller than a thickness of the toner storage part. An exposure device, which is an LED array, is arranged near the tip end part.

Electrophotographic apparatus for forming a color image utilizing LED array exposure devices

An electro-photographic apparatus for conducting printing includes a fixing member fixing an unfixed toner image on a surface of a recording medium onto the recording medium. The fixing member includes a heating roller and a pressurizing member, and a mounting member on which the pressurizing member is mounted. The pressurizing member is supported by the mounting member in a substantially center part in a longitudinal direction of the pressurizing member.

Electro-photographic apparatus with a heating roller and pressurizing member

A fixing unit that is provided in an image forming device and fixes a toner image transferred to paper is constructed of two belts, belt guides each of which guides the inner periphery of each of the belts, a heating member arranged in one of the belts or heating members arranged in both of the belts, a drive roller for driving the inner periphery of the belt, wherein the belts pinch paper on both surfaces thereof by the belt guides and carry the paper. This construction can realize a fixing unit reduced in size and capable of printing images at high speeds and shortening a rise time that elapses until the fixing unit reaches a fixable temperature.

Heat fixing unit with improved belt handling

Provided is a small-sized electrophotographic apparatus having a double face printing function, which can print at a high speed even during double face printing. There are provided a recording medium conveying pathcomposed of a vertical conveying pathfor upward conveying a sheet fed from a sheet cassette, outside of a developing means, a curved conveying pathand horizontal conveying pathfor conveying the recording medium to a transfer means, a fusing meanslocated in the horizontal conveying path, downstream of the transfer means, for fusing a toner image on the recording medium, a sheet discharge tray, a bypass conveying path for guiding a sheet to be subjected to double face printing, having one surface for which printing has been completed, a first branch meansfor guiding the sheet to be subjected to double face printing from a conveying path for the sheet discharge trayinto the bypass conveying path, a reversing conveying pathfor reversing the sheet conveyed in the bypass conveying pathduring double face printing, a second branch meansfor guiding the sheet which has been reversed in the reversing conveying path, into the horizontal conveying path, and a return conveying pathfor returning the sheet which has passed through the second branch means, into the return conveying pathfor conveying the sheet to the horizontal conveying path.

Electrophotographic apparatus

An image forming apparatus, having imaging units arranged alternately on both sides of a continuous paper web, is characterized by minimized image misregistration and reduced processing cost. In order to prevent possible color misregistration caused by changes in paper feed path length resulting from the eccentricity of each drive roller, the difference in the eccentric phases of the rollers on the front and back surfaces is controlled, thereby minimizing the difference in changes in paper feed path length.

Image forming apparatus for printing an image on both sides of a recording medium

A belt driving apparatus which inhibits a belt meandering so as to improve a printing quality and rapidly starts a printing motion at a time of starting the apparatus such as a time of turning on power or the like, and an image forming apparatus using the same. The belt driving apparatus has an endless belt, a plurality of belt tension supports for supporting the belt in a tension manner, and a steering roller supported in a tiltable manner and compensating a meandering of the belt, and the belt driving apparatus is provided with a meandering compensation sensitivity adjuster for adjusting a belt meandering compensation sensitivity of the steering roller per an angle of incline.

Belt driving apparatus and image forming apparatus using the same

An image forming apparatus has an endless belt which serves as an image carrier is characterized by reduced image misregistration and reduced machining cost. When the endless belt feed path is divided into a path from a drive roller to a tension roller, and a path from the tension roller to the drive roller, the eccentricity of an idle roller located on the path on the side including a latent image forming point is set to a value smaller than that of an idle roller located on the path not including the image forming point.

Image forming apparatus having belt-shaped carrier

An image forming apparatus is provided in which a misregistration of an image forming-position due to a tension, acting on a continuous recording medium, and a fluctuation thereof, is corrected with a low-cost construction to provide an image of high quality. A pair of recording medium speed detection devices are provided upstream and downstream of an image forming section, respectively, and a misregistration correction amount is calculated from a detected recording medium feed speed so as to correct the image forming position.

Image forming apparatus

An image production apparatus includes at least one image production unit having a latent image forming device for forming a latent image on an image carrying member and a developing device for attaching toner to the latent image formed by the latent image forming device. A toner image formed by the image production unit is transferred to a transfer medium to produce an image. The image production apparatus further includes a periodicity giving device for giving periodicity to movement in a main scanning direction of the image carrying member or transfer medium. According to this periodicity, the movement time from an image forming position to a transfer position, or the movement time of a transfer medium between adjacent transfer positions is set equal to an integral multiple of the period.

Image production apparatus

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Toride, Japan

Kenji Asuwa