Sharp Kabushiki Kaisha Corporation

Yuichi Kazaki

Yasutaka Maeda

Takayuki Yamanaka

Hiroaki Nakaya

Hideyuki Nishimura

Eiichi Kido

Katsuhiro Nagayama

Atsushi Inoue

Hiroshi Kawamoto

Yoshie Iwakura

Kazuyuki Ohnishi

Yoichi Shimazawa

Taisuke Kamimura

Hiroshi Kawahito

Syouichi Fujita

Itaru Kawabata

Yoshiki Ichikawa

Osamu Wakuda

Tsuyoshi Miyamoto

Natsuko Tanaka

Masahiro Tsuji

Mihoko Okada

Takao Hiroyasu

Shin-ichirou Ohhashi

Fumito Mizoguti

Tsutomu Sugimoto

Shintarou Hatano

A developing unit for visualizing an electrostatic latent image formed on a photoreceptor drum with a toner, includes: a hopper for storing a developer; a developing roller for supplying the toner to a photoreceptor drum on which an electrostatic latent image is formed; and an agitating and conveying portion. In the developing unit, the agitating and conveying portion includes first and second agitating and conveying belts, each having toner agitating blades for agitating and conveying the toner. The first and second agitating and conveying belts are rotatably arranged in the hopper with their rotational axes set approximately vertically so as to rotate the toner agitating blades approximately horizontally.

Developing unit and image forming apparatus using the same

One embodiment of an image forming apparatus according to the present invention includes an image forming apparatus provided with a one-component development apparatus having a toner layer regulating blade for regulating a thickness of a toner layer on a surface of a developer bearing member that contacts a photosensitive body, wherein at a non-development time after completion of operation of the developer bearing member, the developer bearing member is caused to rotate slightly in a direction reverse to that during development.

Image forming apparatus provided with one-component development apparatus

An developing device in which a developing roller develops an electrostatic latent image on a photo conductor; a developing roller driving unit rotates the developing roller in a forward direction and in a backward direction respectively while development is performed and not performed; a thickness regulating member, which is pressed against a surface of the developing roller, regulates a thickness of developer adhered to the surface of the developing roller; and a suppression unit suppresses a pressing force of the thickness regulating member when the developing roller is rotating in the backward direction.

Developing device having thickness regulating member and image forming apparatus

A developing device includes a developer tank, a developing roller, a supply roller, a stirring member, and a doctor blade. The developing device is provided with: a cleaning member detachably provided on a contact portion of the doctor blade with the developing roller, which slides to rub a surface of the doctor blade upon contacting; a supporting section for supporting the cleaning member so as to be capable of being attached to and detached from the contact portion of the doctor blade with the developing roller; and a driving mechanism for moving the cleaning member so as to be attached to and detached from the contact portion of the doctor blade with the developing roller.

Developing device for prevention of coagulate toner adherence and image forming apparatus using the developing device

A developing device incorporating a developer supply unit and a developer discharge section, in which a supply developer including a mixture of toner and carrier is successively supplied to a developer container from the developer supply unit and a deteriorated developer in the developer container is discharged through the developer discharge section. The developer supply unit has a sponge roller for selectively attracting toner to a surface thereof, a magnet roller for selectively attracting carrier to a surface thereof, and a member for scraping and bringing the toner and carrier attracted to these rollers into the developer container. The developer including toner and carrier in a predetermined ratio is thus stably supplied to the developer container. In another example of the developer supply unit, agitating of the developer is performed while shovelling the developer deposited in a lower part of the unit by a transport screw. With this structure, since the toner and carrier are evenly mixed in the unit, the developer having a uniform toner concentration is supplied to the developer container, thereby continuing satisfactory development.

Developing device with developer-supplying mechanism

An image forming apparatus is designed to compensate for voltage to be applied to an exposure lamp and a charger in accordance with changes in the density of a toner image formed on a photoreceptor that occur from its initial state to its final state after an image forming operation. More specifically, the density of a reference toner image is measured by a toner-density sensor. The amount of change in the density is measured beginning with its initial state by a subtracter, and the amount of compensation for the voltage required for obtaining the optimum image quality is found. By using these amounts of compensation as teaching data, learning is made as to the relationship between the amount of change in the density and the amount of compensation in a neurocomputer. Upon forming an image, the neurocomputer executes operations in accordance with the contents of the learning based on an inputted amount of change in density, and finds an appropriate amount of compensation. With this arrangement, it is possible to constantly obtain copied images having stable image quality, and to lower the cost of image forming apparatuses by reducing the number of parts used for the sensors or other devices.

Image forming apparatus having an image-quality correction function

A color balance adjusting apparatus is used for a full color copier in which an original image is illuminated by a light source; the illuminated image is exposed onto a photoreceptor to form electrostatic latent images corresponding to first, second and third colors for creating a color image; and each of the formed electrostatic latent images is developed into a visualized toner image. The color balance adjusting apparatus includes an infrared sensor for detecting toner density of the toner image formed with a toner having any one color of the first, second and third colors. The apparatus further includes automatic adjustment means which determines a relation of light intensity to toner density detected for one color by varying light intensity of said light source, and which determines optimal light intensity for the other two colors as predetermined functions of obtained optimal light intensity. Using this apparatus, automatic adjustment of the color balance for each copy mode can be effected in a short time with lesser consumption of electricity and supplies.

Color balance adjusting apparatus for full-color copier

A full color copying machine which includes intermediate transfer medium whereon toner images having respective color components, formed on a photoreceptor are transferred to form one color toner image, and a screen filter disposed so as to be freely inserted or removed in or from a path of exposure light, which filters the exposure light for exposing the photoreceptor into a pattern of lines. A plurality of color toner images obtained by executing a plurality of copying processes based on a plurality of exposures applied to an original document are superposed on the intermediate transfer medium to form a color toner image. The copying machine further includes a screen mode for inserting a screen filter into a path of exposure light and a normal mode for removing the screen filter from the path of exposure light. Thus, exposures intended for low density components and high density components in an original document image are respectively performed by the use of the different modes, or they are respectively performed by changing setting conditions of the screen filter in the screen mode. With these arrangements, efficient application of the exposure device and high quality of the copied images can be achieved.

Full color copying machine

Growing community of inventors

Kashiba, Japan

Yuichi Kazaki