Sharp Kabushiki Kaisha Corporation

Susumu Murakami

Yoshie Iwakura

Kuniaki Nakano

Hideshi Izumi

Minoru Tomiyori

Takahiro Fukunaga

Hideaki Kadowaki

Masashi Hirai

Yasushi Matsutomo

Kazuya Hamaguchi

Tomohiko Fujii

Toshiaki Kagawa

Toshiki Takiguchi

Takashi Mukai

Atsushi Ide

Toshiya Mikita

Takashi Hori

Takateru Yamamoto

Motoaki Okitsu

Masanori Yamada

Takahisa Narikiyo

Koji Katamoto

Tadaaki Kawano

Tomonori Ohata

Naoya Okamura

Akira Kohno

Yasuhiro Takai

Tomohiko Okada

Yoshiaki Ibuchi

Kimihide Tsukamoto

Mikio Kakui

Toshiaki Ino

Hideaki Hagihara

Tomomi Tanaka

Syouichi Fujita

Yoshiaki Masuda

Tatsuya Shinkawa

Yasuhiro Nishimura

Hiroaki Hori

Yoshiaki Hiramoto

Motokazu Nakao

Masanobu Yamamoto

Ginga Nakamura

Takashi Makiura

Shigeru Yoshida

Masaru Nishijima

Haruyoshi Migita

Takashi Miyaji

Yoshiyuki Nagai

Toshihiro Horiuchi

Fukusaburo Ito

Shinichiro Hiraoka

Kazuaki Ishikawa

Kunihiko Sakaguchi

Yoshiaki Kojoh

Seiichii Kizu

Atsushi Saito

Kouji Aoki

A recording material conveying device includes a stripping claw being in contact with one rotary body of a first pair of rotary bodies, and a supporting member supporting a recording material curved when a jam occurs. The supporting member includes a supporting section located more away from the stripping claw than an imaginary straight line (C) passing a nip portion of the first pair of rotary bodies and a surface on a conveying path's side of the stripping claw, and the supporting section supports the recording material curved when the jam occurs. The recording material conveying device further includes a conveyance guide that is disposed on the downstream side from the supporting member and is displaced toward a pressed direction by a pressing force acting when the curved recording material comes into contact with the conveyance guide.

Recording material conveying device and image forming apparatus

A Transfer device () includes an intermediate transfer belt (), a plurality of intermediate transfer roller (A-D) and a transfer member moving mechanism (). The transfer member moving mechanism moves the intermediate transfer rollers (A-D) between pressing positions causing the intermediate transfer belt () to be pressed against respective photoreceptor drums (A-D) and separate positions causing the intermediate transfer belt () to be separate from the respective photoreceptor drums (A-D). The transfer member moving mechanism () causes a second pressing position of the intermediate transfer roller for monochrome (A) in monochromatic image forming to be different from a first pressing position of the intermediate transfer roller for monochrome (A) in full-color image forming so that an amount of pressing of the intermediate transfer belt () by the intermediate transfer roller for monochrome (A) becomes greater in monochromatic image forming than in full-color image forming.

Transfer device

An image forming apparatus determines the amount of cleaning toner that is supplied to each of an intermediate transfer beltand a secondary transfer beltbased on the number of sheets that have been fed with the pick-up side of the sheet opposed to the intermediate transfer beltand the number of sheets that have been fed with the pick-up side of the sheet opposed to the secondary transfer beltintegrally forms on the intermediate transfer beltcleaning toner images that are supplied to each of the intermediate transfer beltand the secondary transfer beltand switches the application and the stop application of the transfer voltage for transferring the toner image from the intermediate transfer beltto the secondary transfer rollerat a timing corresponding to the determined amount of toner.

Image forming apparatus

An image forming apparatus includes: a transfer portion that transfers a toner image from a first image forming element to a second image forming element when transfer voltage is applied; and a control portion, at time of cleaning the plurality of image forming elements, after integrally forming a cleaning toner image to be supplied to the first image forming element and the second image forming element on the surface of the photoreceptor along a revolving direction, that controls the application of the transfer voltage to the transfer portion to transfer the toner image in a manner such that the toner image is divided into at least four sections along the revolving direction, out of which at least two sections that are not adjacent to each other are transferred from the first image forming element to the second image forming element.

A fixing device of the present invention includes: an external heating belt which is to contact with a surface of a fixing roller so as to heat up the fixing roller; and a cleaning member (a scraper and/or cleaning pad) which is to contact with the external heating belt. The cleaning pad which is impregnated with silicone oil is to contact with a surface of the external heating belt, thereby applying the silicone oil (release agent) to the surface of the external heating belt. This makes it possible to prevent generation of an offset.

Fixing device and image forming apparatus having same

In a fixing device including (i) an external heat belt which abuts against a surface of a fixing roller so as to heat the fixing roller and (ii) a cleaning member which abuts against the external heat belt, a fixing temperature, which is a surface temperature of the fixing roller during a fixing process, is set per group into which recording media to be subjected to the fixing process are divided according to their widths in a direction of a rotary axis of the fixing roller, in such a way that the fixing temperature is set to a lower temperature for a group of narrower widths. This makes it possible to prevent a reduction in releasability of the fixing roller caused by a material, which is scraped off from the external heat belt by the cleaning member and then adhered to the fixing roller, thereby preventing the high-temperature offset.

Fixing device, image forming apparatus, and method for controlling fixing device

A sheet separation mechanism includes a separation claw holder, a separation claw, a first coil spring and a second coil spring. The separation claw holder can be provided at a predetermined place in the image forming apparatus. The separation claw includes a separation claw base pivotally supported by the separation claw holder and a separation claw front-end pivotally supported by the separation claw base. The first coil spring is configured to apply a force to rotate the separation claw base toward an intermediate transfer belt. The second coil spring is configured to apply a force to rotate the separation claw front-end toward the intermediate transfer belt.

Sheet separation mechanism and image forming apparatus with first and second biasing members

An image forming apparatus includes a transfer belt unit which has an intermediate transfer belt for supporting toner images and primary transfer rollers for pressing the intermediate transfer belt against corresponding photoreceptor drums and moves the intermediate transfer belt along the surface of each photoreceptor drum to transfer the toner images to the intermediate transfer belt. The intermediate transfer belt is formed so as to be 30 &#x3bc;m to 50 &#x3bc;m in average thickness, each primary transfer roller is arranged at a position, along the moving direction of the intermediate transfer belt, which is deviated downstream with respect to the moving direction from the position where the intermediate transfer belt is in contact with the photoreceptor and which is projected toward the photoreceptor drum side so as to press the intermediate transfer belt against photoreceptor with a nip pressure ranging from 10 gf/cmto 40 gf/cm.

Transfer belt unit and image forming apparatus using the same

An intermediate transfer unit mounting and dismounting mechanism for an image forming apparatus including a transfer belt unit that is provided as a separate structure from the apparatus body and can be mounted to and dismounted from the apparatus body, includes: a coupling/decoupling manipulator disposed at the coupling portion between the intermediate transfer unit and the apparatus body for coupling/decoupling. The coupling/decoupling manipulator includes a threaded portion to fasten the intermediate transfer unit and the apparatus body and a drive gear for transferring driving force for conveying the intermediate transfer belt. While the threaded portion is rotated to release the fastening between the transfer belt unit and the housing, the transfer belt is conveyed by the drive gear that rotates in linkage with the rotation of the threaded portion.

Intermediate transfer unit-mounting and dismounting mechanism and intermediate transfer unit-mounting and dismounting method

For an electrostatic latent image formed on an image carrier (), besides an operation forming an 'image forming electrostatic latent image' used to form the primary image, an operation is executed that forms an 'electrostatic latent image for removing developer' for removing developer that resides on a developer supply member () for a predetermined time period onto the image carrier (). Thus, developer is nearly eliminated from residing on this developer supply member () in an overcharged state for a long period of time, and generation of a fogged image is avoided as much as possible.

Image forming apparatus capable of preventing worsening of image quality caused by excessively charged developer

A charging apparatus having a corona electrode is provided which exhibits high durability against ozone and moisture in the air, which can charge a surface of a photoreceptor drum stably throughout the life of an image forming apparatus, and which can be manufactured at a low cost. In a charging apparatus including corona electrode having a flat plate section and a pointed projection section, a support member, a shield case, and a grid electrode, a coating layer including a material different from the material of the corona electrode is formed at least on part of the surface of pointed projections constituting the pointed projection section.

Charging apparatus and image forming apparatus

An electrostatic charger according to the present invention includes a needle electrode, a support, and a cleaning member. The needle electrode has a linear array of needles. The support can move along the linear array. The cleaning member is supported by the support rotatably on an axis perpendicular to the linear array. While the support is moving with the cleaning member along the linear array, the cleaning member rotates, with the needles sinking in order into and subsequently coming in order out of the cleaning member. When the cleaning member makes each rotation while moving with the support, some of the needles sink in positions into the cleaning member where any other needles did not sink when the cleaning member made the previous rotation.

Electrostatic charger

An image forming apparatus includes a photoreceptor, a cleaning unit, an exposing unit, a developing unit, and a control section. On a circumferential surface thereof, the photoreceptor has an image area to have contact with a record medium in an image forming process, and a non-image area. The cleaning unit has a blade in contact with the image and non-image areas. The exposing unit forms an electrostatic latent image on the surface by irradiating the surface along a fast scanning direction with light modulated according to image data supplied by the control section. The data includes primary image data for modulating light to irradiate the image area with. The developing unit develops the latent image by applying developer to the surface. The control section performs an image addition processing in which secondary image data for modulating light to irradiate the non-image area with is added to the primary image data.

Image forming apparatus that adds a toner image to a non-image area of a photoreceptor to prevent warping of cleaning blade

Growing community of inventors

Kyoto, Japan

Susumu Murakami