Sharp Kabushiki Kaisha Corporation

Mitsuyoshi Terada

Yoshinobu Tateishi

Toshio Yamanaka

Yuhi Akagawa

Hideaki Kadowaki

Hiroshi Tachiki

Osamu Fujimoto

Keizo Fukunaga

Kazuhiro Matsuyama

Masashi Hirai

Fumio Shimazu

Kiyoshi Toizumi

Tadasu Taniguchi

Toshiya Mikita

Atsuyuki Katoh

Kouichi Yamauchi

Hiromu Yoshimoto

Takuya Abe

Takayuki Ohno

Yuji Nakagawa

Yoshikazu Harada

Masaru Tsuji

Eiichi Kido

Toshihide Ohgoshi

Toshiaki Ino

Takayuki Yamanaka

Takashi Kitagawa

Hiroaki Yoshida

Yoshikazu Kondoh

Shinichi Azumi

Toyokazu Mori

Takashi Makiura

Hiroshige Araki

Koichi Nakamura

Naoyuki Yamane

Takashi Sugito

Koichi Yamauchi

Kaori Fujii

Atsuyuki Kato

Hideki Gotoh

A protecting cover and a pickup device, each having a hooking portion, are rotatably provided at the flank of an image forming apparatus. The rotational centers of the protecting cover and the pickup device and the hooking portions are arranged in such geometry that the hooking portions become engaged with each other only in the range from a predetermined trace intersection to the flank of the image forming apparatus when the protecting cover is rotated from its usage position toward its retracted position at the flank of the image forming apparatus. The pickup device is stopped at the starting position of engagement where the hooking portions are positioned at the trace intersection when sheet feed is not made, and is moved to the operating position when sheet feed is to be made. The protecting cover is constructed so as to rotate in linkage with the rotation of a paper feed tray which is rotatably provided at the flank of the image forming apparatus.

Sheet feeder and image forming apparatus having the same

An image forming apparatus transfers a toner image formed on a photoconductor drum onto a sheet-like recording member while the sheet-like recording member is transported and attracted to a transfer belt, and comprises a jam handling control unit for detecting a transport fault of the sheet-like recording member, and for stopping the transport operation when the transport fault is detected. When the transport fault is detected in a section other than a fixing section, the jam handling control unit first causes the transport operation of the fixing section, and thereafter causes the transfer belt and the transport operation on the upstream side thereof to stop, and any sheet-like recording member remaining on the transfer belt so that the transport mechanism on the upstream side thereof is transported and stopped at the position spanning between the area of the fixing section and the area of the transfer belt.

Image forming apparatus

An optical electric charge removal device mountable on an image formation apparatus of an electrophotographic system for removing residual charges on a photosensitive member by light irradiation is provided. The optical electric charge removal device includes a point light source provided in the image formation apparatus; and an optical conductor, mountable on a process cartridge which is detachable from the image formation apparatus, for guiding light incident from the point light source to the photosensitive member.

Optical electric charge removal device and image formation apparatus including the same

In an image forming device of the present invention, which is a tandem type, electrophotographic image forming device, a first separating/contacting mechanism mechanically lowers/raises the whole of a transfer frame holding the transfer and transport belt unit in association with the opening/closing of a front door, a second separating/contacting mechanism mechanically lowers/raises the right side of the transfer frame in association with the opening/closing of a right side door, and a third separating/contacting mechanism mechanically lowers/raises the left side of the transfer frame in association with the opening/closing of a left side door. Therefore, the handling of a paper jam can be carried out even when power supply is cut off, and the transfer frame can be separated from the photoconductor drums just by opening a door from a plurality of access directions, on a side opened.

Image forming device

An image forming apparatus of the present invention includes a photoreceptor drum on which a toner image is formed, a transfer drum for transferring the toner image formed to transfer paper by bringing the transfer paper into contact with the photoreceptor drum, and a pair of register rollers for supplying the transfer paper to the transfer drum at a predetermined time and for curling the transfer paper in an arc. The register rollers include first and second rollers pressed against each other, the first roller being a predetermined hardness and the second roller being a hardness larger than the first roller. The transfer drum is disposed on the same side as the second roller with respect to an imaginary tangent line touching the surface of the second roller at one end of a contact section between the first and second rollers. The image forming apparatus also includes transporting means for supplying the transfer paper to the register rollers so that a front edge of the transfer paper comes into contact with the second roller, temporarily stops, and then continues to the transfer drum. The image forming apparatus also includes a means for changing the pressure that the register rollers are pressed together. Paper type, quality, thickness, and size are detected and the pressure is adjusted accordingly. The means for changing pressure includes a resilient member for the pressing the second roller against the first, and a changing member for changing the amount of deformation of the resilient member.

Image forming apparatus equipped with register rollers for curling

An image forming apparatus having a main body whose upper section is split into first and second split lid sections. The first and second split lid sections are arranged to be freely opened and closed. A transfer body and a fixing device are detachably installed in the first split lid section, while a developing device and an image carrying body are installed in the second split lid section. The image carrying body and the transfer body are brought out of contact with each other by opening at least one of the first and second split lid sections. The transfer body and a fixing member are caused to be rotatable by opening the first lid section. With this structure, it is possible to easily repair a paper jam and perform maintenance of the respective sections without increasing the installation space.

Image forming apparatus having easily replaceable components

An image forming apparatus of the present invention includes a photoreceptor drum on which a toner image is formed, a transfer drum for transferring the toner image to paper by bringing the paper into contact with the photoreceptor drum, the transfer drum having a dielectric layer, a semi-conductive layer and a conductive layer laminated in this order from the paper side, a power source which is connected to the conductive layer so as to apply a predetermined voltage to the conductive layer, and a conductive roller for pressing the paper against a surface of the dielectric layer so as to produce a potential difference between the conductive layer and the paper. The potential difference induces charges of the same polarity as the voltage applied to the conductive layer on the surface of the dielectric layer, and charges of the opposite polarity on a back surface of the paper pressed against the surface of the dielectric layer. Thus, the paper electrostatically adheres to the transfer drum in a satisfactory manner. Moreover, unlike charging by atmospheric discharge, since the surface potential of the transfer drum is stable, it is possible to prevent unsatisfactory transfers and improve the image quality.

Transfer device for an image forming apparatus

An object of the invention is to prevent a silicone gas generated in a fixing unit from entering into a charger. A corona wind rises when the charger corona-discharges, and air is taken in through an outside-air intake. The air flows in through the air passage and the air inlet and flows out through a front opening as an air flow. The silicone gas is isolated by the airflow and prevented from entering into the charger.

Image forming apparatus with isolated silicone gas

A toner image fixing device comprises a heat roller and a lamp heater. The lamp heater is formed from a nicrome wire stretched between clamp terminals, a silica tube and ceramic holders closely fitted to respective ends of the silica tube and which have an external diameter which is substantially the same as the diameter of the heating roller. The lamp heater is secured by a lamp holder and frame to the shaft of the heat roller. The heat roller is rotatably supported by a bearing and is driven by a driving gear.

Toner image fixing device having improved lamp heater

Growing community of inventors

Osaka, Japan

Mitsuyoshi Terada