Canon Kabushiki Kaisha

Yasuo Yoda

Kenji Watanabe

Kenichi Iida

Katsuhiko Nishimura

Tatsunori Ishiyama

Koichi Hiroshima

Takahiro Uchiyama

Yasunari Kobaru

Toru Kosaka

Tatsuya Nakamura

Hiroshi Mano

Kimio Nakahata

Yuki Nishizawa

Shinichi Tsukida

Masahide Hirai

Hiromichi Yamada

Masuo Yamazaki

Takashi Shibuya

Naoto Tsuchihashi

Yoshiki Kudo

Masami Takeda

Hisahiro Saito

Tohru Kosaka

Tohru Saitou

Akira Kato

Atsushi Ogata

Hiroshi Hagiwara

Akira Kuroda

Takaaki Tsuruya

Minoru Hayasaki

Aoji Isono

Tomoaki Nakai

Akinobu Hirayama

Michio Uchida

Atsuyoshi Abe

Eiji Uekawa

Yoichiro Maebashi

Tetsuya Sano

Tatsuaki Orihara

Hiromitsu Kumada

Takateru Ohkubo

Takeshi Kawamura

Hidetoshi Hanamoto

Toshikazu Tsuchiya

Shuhei Watanabe

Hiroki Eguchi

Yoshiko Kubo

Masatake Usui

Hiroshi Kawaguchi

Kentaro Yamashita

A cylindrical fixing member for use with a fixing device includes a heat generating layer and an electrode layer contacting the heat generating layer. The electrode layer is smaller in volume resistance value than the heat generating layer. The electrode layer is formed in a helical shape so that a helical axis thereof extends in a direction along a generatrix direction of the fixing member. One end and the other end of the electrode layer are electrically open.

Cylindrical fixing member, fixing device and image forming apparatus

An image forming apparatus includes: a photosensitive member configured to be rotated; scanning means for scanning, by light corresponding to image data, the photosensitive member that is charged, thereby forming an electrostatic latent image on the photosensitive member; and a contacting member in contact with the photosensitive member to form a nip portion. In a correction mode in which a shift of an image is corrected based on a detection result obtained by detecting, at the nip portion, an electrostatic latent image for correction formed on the photosensitive member by the scanning means, a width of the electrostatic latent image for correction is equal to or more than a width of the nip portion in a rotation direction of the photosensitive member.

Image forming apparatus that detects electrostatic latent image for correction

An image forming apparatus includes a toner carrying member for carrying a toner; an image carrying member on which a toner image is formed with the toner; and a plurality of divided electrode portions provided at a position in which the electrode portions oppose the toner carrying member via the image carrying member interposed therebetween. The electrode portions are supplied with a voltage on the basis of image information to move the toner between the toner carrying member and the image carrying member thereby to form the toner image. The electrode portions includes a first electrode portion for forming an image portion and a second electrode portion, adjacent to the first electrode portion, for forming a non-image portion. The image forming apparatus further includes a controller for variably controlling at least one of potential differences |Vp&#x2212;Vt| and |Vt&#x2212;V0| depending on the image information, where a potential of the toner carrying member is Vt, a potential of the first electrode portion is Vp and a potential of the second electrode portion is V0.

Image forming apparatus

An image forming apparatus includes a toner carrying roller for carrying a toner, an image carrying member, contacting the toner on the toner carrying roller, on which a toner image is to be formed with the toner, and an electrode portion provided at an opposing position in which the electrode portion opposes the toner carrying roller via the image carrying member interposed therebetween. The toner image is formed on the image carrying member by changing a value of a voltage, on the basis of image information, applied to the electrode portion, and the toner carried on the toner carrying roller and the image carrying member contact each other in a toner contact area. The toner is moved between the toner carrying roller and the image carrying member in a toner movement area by changing the value of the voltage applied to the electrode portion, and the toner movement area is present downstream of the toner contact area with respect to a movement direction of the image carrying member.

Image forming apparatus having toner density control

An image forming apparatus includes: an image bearing member configured to bear a toner image; a plurality of electrode portions; a control unit configured to control a voltage applied to the electrode unit based on image information; and a toner bearing member configured to bear toner and form a toner image on the image bearing member according to the voltage applied to the electrode portion, in which &#x3b1;&#x3e;1.22 is satisfied and rx&#x2033;/ry&#x2033; is defined as &#x3b1;, where Dy indicates a thickness of the image bearing member, Dx indicates a distance between the electrode portions adjacent to each other, rx&#x2033; indicates a resistance component of the image bearing member in a direction parallel to Dx and ry&#x2033; indicates a resistance component of the image bearing member in a direction parallel to Dy in a rectangular solid body including Dx and Dy in a side.

The image forming apparatus has an image bearing member bearing an image thereon, and a transfer member contacting with the image bearing member in a contact portion, the image on the image bearing member is transferred to a transfer medium in the contact portion by the transfer member, the Young's modulus of the image bearing member is equal to or greater than 2&#xd7;10[N/m] and equal to or less than 9&#xd7;10[N/m] and contact pressure P between the image bearing member and the transfer member is equal to or greater than 4.0&#xd7;10[N/m] and equal to or less than 7.3&#xd7;10[N/m]. Thereby, there is provided an image forming apparatus which prevents the deterioration of an image even if use is made of an image bearing member of high hardness.

An image forming apparatus includes an image bearing member; a charging device for electrically charging the image bearing member at a contact position; a transferring device for transferring a developed image on the image bearing member onto a transfer material; and a developer charging device for electrically charging a developer remaining on the image bearing member after the image is transferred. The developer charging device is disposed downstream of the transferring device and upstream of the charging device with respect to a moving direction of the image bearing member. An electric field forming device forms a cleaning electric field in a direction of transferring the developer from the developer charging device onto a predetermined region of the image bearing member and forms a cleaning electric field for transferring the developer from the charging device onto the image bearing member after the predetermined region passes through the contact portion.

Image forming apparatus with two cleaning electric fields for transferring developer from a developer charging device onto an image bearing member

An image forming apparatus includes a movable image bearing member, a movable intermediary transfer member, wherein an image on the image bearing member is transferred onto the intermediary transfer member by primary transfer and the image transferred onto the intermediary transfer member is transferred onto a transfer material by secondary transfer, a discriminator for discriminating a kind of the transfer material, and a controller for controlling a moving speed ratio between the image bearing member and the intermediary transfer member on the basis of an output of the discriminator.

Image forming apparatus with control feature based on transfer material discrimination

The image forming apparatus includes, a movable first image bearing member on which a toner image is formed; and a movable second image bearing member which is brought into contact with the first image bearing member and to which the toner image on the first image bearing member is transferred, in which the toner image on the second image bearing member is transferred onto a transferring material, a dot-shaped dot image formed of a toner different from the toner image is formable on the first image bearing member, and the dot image is variable according to a condition upon forming the toner image on the transferring material. Thus, there is provided an image forming apparatus capable of forming a final image with a high quality in a stable manner independently of a selection of a type of transferring materials or image quality mode as well as suppressing an image streak occurrence.

Image forming apparatus including two image bearing members and featuring a variable dot image

The image forming apparatus includes a movable first image bearing member on which a toner image is formed, and a movable second image bearing member which is brought into contact with the first image bearing member and to which the toner image on the first image bearing member is transferred, in which a dot-shaped dot image formed of a toner different from the toner image is formable on the first image bearing member, and in which a distance between dot centers of the dot images is equal to or smaller than a width of a contact part between the first image bearing member and the second image bearing member in a moving direction of the first image bearing member. Consequently, it is possible to steadily suppress an image streak occurrence and to obtain a final image having a high quality in a stable manner.

Image forming apparatus including two image forming members and featuring a dot-shaped image

An image forming apparatus includes an image bearing belt; a supporting roller for supporting the image bearing belt; a transfer roller for forming a nip with the image bearing belt, wherein an image is transferred from the image bearing belt onto a transfer material at the nip by applying a voltage to set transfer roller; wherein the nip has a first nip portion where the transfer roller is contacted to the image bearing belt without being backed up by the supporting roller, and a second nip portion where the transfer roller is contacted to set image bearing belt by being backed up by the supporting roller, the first nip portion being upstream of the second nip portion; and a regulating member for regulating a discharging the direction of the transfer material to be discharged from the nip.

Image forming apparatus having transfer roller forming a nip with image bearing belt and regulating member for same

An image forming apparatus includes an image bearing member for bearing a developer image, a transfer member for electrostatically transferring the developer image onto a transfer material, a power supply for applying a voltage to the transfer member, and an electric current detector for detecting a value of an electric current which flows to the transfer member when the voltage is applied from the power supply to the transfer member. The image forming apparatus controls an output of the power supply by varying the voltage applied to the transfer member by a predetermined voltage quantity in such a manner that the electric current value detected by the electric current detector becomes a target electric current value. The predetermined voltage quantity can be varied.

Image forming apparatus including transfer means with transfer bias output controlled by calculated impedance at predetermined voltage/current

An image forming apparatus includes a plurality of image bearing members for bearing images; and an intermediate transfer member onto which a plurality of images on the plurality of image bearing members is sequentially transferred electrostatically at a plurality of transfer positions, the plurality of images on the intermediate transfer member is transferred onto a recording material, wherein a relationship of &tgr;&lE;T is satisfied in which T (second) is a time taken in order for the intermediate transfer member to move from one transfer position to an adjacent transfer position when a plurality of images is transferred from the plurality of image bearing members onto the intermediate transfer member, and &tgr; (second) is a charge relaxation time of the intermediate transfer member.

An image forming apparatus including a rotatable developing member having a plurality of developing devices for developing an image bearing member at a first developing station, and a second single developing device arranged upstream of the rotatable developing member for developing the image bearing member exclusively at a second developing station different from the first developing station. The second developing device has a cover portion covering the rotatable developing member, and a portion of the cover portion is disposed at a position spaced apart from a rotation axis of the rotatable developing member by a predetermined length in a horizontal direction away from the image bearing member. The rotatable developing member rotates in an opposite direction with respect to the direction of rotation of the image bearing member to prevent toner from scattering toward the optical system.

Image forming apparatus having a rotatable first developing member, and

An image forming apparatus has an image bearing member; toner image forming unit for forming a toner image with non-magnetic toner on an image bearing member; intermediate transfer member contactable to the image bearing member and movable along an endless path; primary transfer unit for effecting primary image transfer of the toner image formed on the image bearing member onto the intermediate transfer member at a first transfer position; secondary transfer unit for effecting a secondary image transfer of the toner image from the intermediate transfer member on the transfer material at a second transfer position; and a residual toner charger for charging the residual toner remaining on the intermediate transfer member to a polarity opposite from a regular polarity thereof. After the secondary image transfer, the residual toner remaining on the intermediate transfer member is charged by the residual toner charger to the opposite polarity, and is then passed through the first transfer position during the primary image transfer, so that the residual toner is transferred back to the image bearing member substantially simultaneously with a next primary image transfer, thus removing the residual toner from the intermediate transfer member.

Image forming apparatus which back-transfers residual toner from an

Growing community of inventors

Numazu, Japan

Yasuo Yoda