Seiko Epson Corporation

Seiko Epson Kabushiki Kaisha

Tomoe Aruga

Ken Ikuma

Tahei Ishiwatari

Yoichi Yamada

Hideya Yokouchi

Hidenori Kin

Kazuhiro Ichikawa

Yoshihiro Nakashima

Yukio Takayama

Yujiro Nomura

Nobumasa Abe

Tadashi Sugiyama

Yoshiro Koga

Nobuyoshi Maekawa

Kiyoteru Katsuki

Kenjiro Yoshioka

Junichiro Shinozaki

Kiyoharu Momose

Hiroshi Niki

Kazuyoshi Fujimori

Toshiaki Ohno

Junichi Okada

Shinji Yasukawa

Masanao Kunugi

Naoyuki Okumura

Kuniaki Tanaka

Yoshio Arai

Akira Kubota

Akihiko Ikegami

Yasuhito Hirashima

Kaneo Yoda

Nozomu Inoue

Ippo Kimura

Hideya Tokouchi

Kenji Okuhara

A developing system comprises: a plurality of image carriers; a plurality of developing devices for developing electrostatic latent images, formed on the plurality of image carriers, with respective liquid developers of different colors of which carrier is nonvolatile solvent; and developer collecting means which are disposed at a plurality of locations for collecting excess developers, wherein the developing devices have developer containers, respectively. The developing system further comprises a carrier storing tank for distributing the carrier to the respective developer containers.

Image forming apparatus that collects and filters excess liquid developer

An image forming apparatus includes a reservoir base section with a recess that receives liquid developer scraped off of a developing roller by a cleaning blade. The recess is substantially U-shaped with an opened top side and an arc angle of not less than 180&#xb0;. A conveying base station is continuous with the reservoir base section and has a conveying port formed thereon. A conveying member arranged in the reservoir and conveying base sections conveys liquid developer through a hollow path from the recess to the conveying port by rotating about its axis. The radius rof the outer periphery of the conveying member, the radius rof the conveying port and the radius rof curvature of the recess have the relationship r&#x3c;r&#x3c;r

Developer conveying apparatus and image forming apparatus using the same

The invention provides a developing device employing a liquid developer which is capable of effectively cleaning a development roller or the like having an elastic outer layer. The developing device of the invention is provided with an elastic roller such as a development roller for developing a latent image formed on an image carrier. In image forming process, toner particles uniformly dispersed in carrier are agglutinated to the elastic roller side by means of compaction. A cleaning blade is provided for cleaning the agglutinated toner particles. Assuming that an angle of a contact face of the cleaning blade relative to a perpendicular line perpendicular to a generating line of the elastic roller at a contact point where the tip end of the cleaning blade is pressed against and in contact with the elastic roller is &#x3b8; and an angle of a rising contour of a deformed portion of the elastic outer layer which is deformed by the pressure of the cleaning blade against the elastic roller relative to the perpendicular line is a, a relation a&#x3e;&#x3b8; is established.

Developing device having cleaning blade for cleaning development roller

A developer collection system comprises a plurality of image carrier members, a plurality of development sections for developing the electrostatic latent images formed respectively on the plurality of image carrier members by means of liquid developers of different colors containing a non-volatile solvent as carrier, an intermediate transfer member for sequentially transferring the developer images developed by the primary transfer sections respectively corresponding to the plurality of image carrier members, superposing them one on the other and carrying and conveying the developer images, an output section for transferring the superposed developer images from the intermediate transfer member onto a sheet on a sheet conveyance route in the secondary transfer section and developer collection means for collecting excessive developers from at least two of the plurality of image carrier members, the plurality of development means, the intermediate transfer member and the output section and at least two of the flow channels from the developer collection means are merged to form a single flow channel.

Developer collection system and image forming apparatus using the same

Developing system that distributes carrier to developer containers in a manner to achieve stable image formation

Developing device

A fusing unit for fusing a nonfused toner image formed on a sheet medium, including: a heating roller; a pressing roller pressed to the heating roller; a heat-resistant belt which is wrapped around an outer periphery of the pressing roller and travels while being nipped at a nip portion between the pressing roller and the heating roller; a belt stretching member which stretches the heat-resistant belt; and a sliding member which is disposed between the belt stretching member and the pressing roller and slides along the outer periphery of the pressing roller, wherein the sliding member is disposed to be brought into contact with the heating roller through the heat-resistant belt at a contact portion.

Fusing unit that stabilizes a contact nip region

In a fixing device for causing a pressurizing roller to come in pressure contact with a heating roller including a central region heating heater for heating a central region and a side end region heating heater for heating a side end region on an outside of the central region, thereby fixing an unfixed toner, or an image forming apparatus comprising the fixing device, an outside of an image region of the heating roller is caused to have a peak of heat distribution of the central region heating heater and heat radiated from both side ends of the heating roller is compensated to flatten the temperature distribution of the image region, thereby preventing a deterioration in an image.

Fixing device and image forming apparatus including a heating roller with multiple heaters

There is disclosed a device for fixing a toner image on a recording medium. A heat source is incorporated in a first roller. A heat-resistant belt member is stretched by a second roller and a stretcher and circulated therearound. The belt member is brought into contact with the first roller to form a nip portion therebetween through which the recording medium is passed. At least one of the first roller and the second roller is provided with a cylindrical core member and a rubber layer. The cylindrical core member is formed with a first portion having a first diameter, a second portion having a second diameter which is smaller than the first diameter, and a step portion continuously connecting the first portion and the second portion. The rubber layer is secured to an outer periphery of the core member so as to cover at least the first portion and a part of the step portion.

Fixing rubber roller, fixing device and image forming apparatus incorporating the same

An image forming apparatus comprises: an image transfer carrying meanshaving flexibility and having an endless sleeve-like shape; a plurality of image forming meanswhich are arranged along the image transfer carrying meanssuch that respective image carriersthereof are in contact with the image transfer carrying meanseach image forming meanscomprising a latent image forming meansfor forming a latent image on the image carrier and a developing means for developing the latent image formed on the image carrier; and transfer bias applying meanswhich are disposed on the back of the image transfer carrying means at positions where the respective image carriers are in contact with the image transfer carrying means for applying transfer bias. The image transfer carrying meansis laid around at least two rollers with certain tension and is positioned to be in contact with the image carriersto have predetermined nip width therebetween and each transfer bias applying means abuts the image transfer carrying meansto have a contact area narrower than the nip width for applying transfer bias. At gradually increasing spaces at the entrance end and the exit end of each nip portion of the image transfer carrying means, even with high transfer bias voltage, the discharge phenomenon and an undesired phenomenon of toner image scattering from predetermined positions are prevented, thus preventing the deterioration of image quality.

Image forming apparatus

In a device for fusing a toner image on a recording medium, a first roller provided with a heat source and a second roller are provided. A stretcher is elongated in a longitudinal direction of the second roller. An endless belt is stretched by an outer circumferential face of the second roller and a first face of the stretcher, and circulated in accordance with rotation of the first roller and the second roller. The endless belt is sandwiched between the first roller and the second roller to form a nipping portion through which the recording medium passes to fuse the toner image thereon. A supporter is disposed between the second roller and the stretcher. The supporter is elongated in the longitudinal direction of the second roller, and is provided with at least one first projection having a first face which is brought into slide contact with at least a longitudinal center portion of the outer circumferential face of the second roller.

Fusing device with stable nipping portion

In a fixing device for fixing a toner image onto a recording medium, a heating roller is provided with an elastic layer formed on an outer periphery thereof. An endless belt is adapted to be circulated. A press member presses a part of the endless belt against the heating roller so as to deform the elastic layer, thereby forming a fixing nip portion through which the recording medium it passed. A guide member has a slope portion extended so as to close to a tangential line defined at a press contact position between the heating roller and the press member, as is being away from the exit of the fixing nip portion. A fixing pressure generated at the exit of the fixing nip portion is greater than a fixing pressure generated at an entrance of the fixing nip portion.

Fixing device and image forming apparatus incorporating the same

A transfer belt unit and image forming apparatus that achieves the reduction in size and cost of a transfer belt unit and can prevent fluctuation of the cleaning performance. The unit has a transfer belt, and a plurality of rollers around which the transfer beltis laid with certain tension, wherein at least one of the rollers is a tension rollerfor tensioning to the transfer belt; frames supporting the plurality of rollers; tensioning mechanisms which are disposed on the side faces of the frames to bias the tension roller in a belt tensioning direction; a cleaning device in contact with the transfer belt at a position opposing the tension roller; rotation preventing members which prevent the rotational torque from being transmitted to the cleaning device; and position restricting members which restrict the relative position between the cleaning device and the tension roller.

Transfer belt unit and image forming apparatus using the same

A fixing device for fixing an unfixed toner image formed on a sheet-shaped recording medium is disclosed. A first roller incorporates a heat source therein. A second roller is pressed toward the first roller. A part of an endless belt is wound on an outer periphery of the second roller to be circulated. A non-rotatable belt stretcher stretches the endless belt together with the second roller such that the circulated endless belt is slid on a first face extending in a widthwise direction of the endless belt, and such that a tensile force is applied to both widthwise end portions of the endless belt. The circulated endless belt is nipped between the first roller and the second roller to form a first nip portion through which the unfixed toner image is fixed on the recording medium with heat from the heat source. The first face is curved in the widthwise direction.

Fixing device for fixing an unfixed toner image formed on a sheet-shaped recording medium

A belt member is formed with a seam portion by overlapping and adhering both longitudinal end portions thereof to constitute an endless belt stretched and circulated by a rotative, first stretching member and a second stretching member. A length of the seam portion is no less than a length between a first point at which the endless belt is separated from one of the first stretching member and the second stretching member and a second point at which the endless belt is brought into contact with the other one of the first stretching member and the second stretching member.

Belt member incorporated in image forming apparatus

Growing community of inventors

Nagano, Japan

Tomoe Aruga