Ricoh Company, Ltd.

Canon Kabushiki Kaisha

Hiroya Hirose

Satoru Yoshida

Kiyonori Tsuda

Masami Tomita

Takeshi Uchitani

Hiroyuki Nagashima

Shin Hasegawa

Yutaka Takahashi

Toshio Koike

Naohiro Kumagai

Takeshi Shintani

Masanori Kawasumi

Eisaku Murakami

Atsushi Sampe

Masato Yanagida

Mugijiroh Uno

Kazunori Karasawa

Tokuya Ohjimi

Kentaroh Matsumoto

Akira Yamamoto

Atsushi Hosoi

Ryo Hanashi

A developing unit includes a developer carrying member, a supplying compartment, a recovery compartment, and an agitation compartment. The developer carrying member develops a latent image formed on an image carrier with a two-component developer. The supplying compartment has a developer supplying transporter to supply the two-component developer to the developer carrying member while transporting the two-component developer. The recovery compartment has a developer recovery transporter to transport the two-component developer recovered from the developer carrying member. The agitation compartment has a developer agitation transporter to agitatingly transports developer. The developer agitation transporter includes a first screw having a screw pitch to transport developer to an upstream end of the supplying compartment from a downstream end of the agitation compartment. The developer supplying transporter includes a second screw having a given screw pitch, which is greater than a screw pitch of the first screw.

Developing unit having effective developer transportability, and process cartridge and image forming apparatus using the same

A development device includes a developer carrying member, developer supply, developer collection and developer agitation conveyance paths, transfer and communication openings, and partition. The developer carrying member bears a two-component developer. The developer supply and developer collection conveyance paths respectively convey the two-component and collected developers in the first direction. The developer agitation conveyance path conveys excess and collected developers in a second direction while agitating to supply the agitated developers to the developer supply conveyance path. The partition separates the developer collection, developer supply, and developer agitation conveyance paths. The transfer opening transfers the collected developer from the first to the second direction. The communication opening, disposed at a further upstream side of the developer collection conveyance path than the transfer opening in the first direction and at a higher position than the developer collection conveyance path, communicates the developer collection conveyance path with the developer agitation conveyance path.

Development device, and image forming apparatus and process cartridge using the development device

A development apparatus includes three developer conveyance paths with separate functions for the supply, recovery and agitation of a developer, respectively, in which a reduction in size of the apparatus can be achieved. An image forming apparatus includes the development apparatus. By a development region width of a supply opening for delivering developer from a downstream end in the direction of conveyance of an agitation conveyance path to an upstream end in the direction of conveyance of a supply conveyance path and a surplus opening for delivering developer from the downstream end in the direction of conveyance of the supply conveyance path to the upstream end in the direction of conveyance of the agitation conveyance path, a space saving of the upper part of the development apparatus can be achieved and a space saving of the development apparatus as a whole can be achieved compared with a conventional development apparatus.

Development apparatus and image forming apparatus employing the same

A developing device includes a container, a stirring and transferring unit, a replenishing unit, and a discharging mechanism. The container contains developer including toner and carrier. The stirring and transferring unit is located in the container to mix and stir the toner and the carrier, and circulates the developer in the container. The replenishing unit replenishes the container with developer from an opening of the container. The discharging mechanism discharges surplus developer out of the container, and is located on a rotation shaft of the stirring and transferring unit.

Developing device and image forming apparatus

An image forming apparatus includes an electrostatic latent image carrier carrying an electrostatic latent image and a development unit that develops the electrostatic latent image. The development unit includes a developer carrier, first, second, and third developer conveyers, and an opening area. The developer carrier is disposed opposing to the electrostatic latent image carrier. The first developer conveyer supplies a developer to the developer carrier. The second developer conveyer conveys the developer, and transports the developer to the first developer conveyer at a downstream side of the second developer conveyer. The third developer conveyer collects the developer, conveys the developer, and transports the developer to the second developer conveyer in a downstream side of the third developer conveyer. The opening area, disposed higher than a lowermost point of the first developer conveyer, allows the developer to drop from the first developer conveyer to the second developer conveyer.

Image forming apparatus capable of reducing an occurrence of developer depletion in a development unit

An image developer, including a developer bearer rotatable facing an electrostatic latent image bearer; a developer feeder feeding a developer including a toner to the developer bearer; a developer collector collecting the developer separated and left from the developer bearer after the developer is fed to the electrostatic latent image bearer; a detour route including a developer stirrer and transfer stirring and transferring the developer between the developer feeder and the developer collector; a first opening connecting the developer feeder with the detour route; a second opening connecting the detour route with the developer collector; a developer supplier supplying the developer to the image developer; and a third opening connecting to the developer supplier, wherein the toner has a volume-average particle diameter of from 3 to 8 &#x3bc;m and a ratio (Dv/Dn) of the volume-average particle diameter (Dv) to a number-average particle diameter (Dn) thereof of from 1.00 to 1.40.

Image developer providing improved developer dispersibility and image forming apparatus containing the same

A cleaning unit includes a first blade and a second blade. The first blade is in contact with an image carrier or a paper carrier and removes adhered substances remained on surface of these. The second blade has an abrasive layer that is formed by including abrasive particles in an elastic material and is disposed in the downstream side of the first blade. The second blade is allowed to be in contact with the image carrieror the paper carrier. Volume occupancy of abrasive particles in an area of contact of the second blade with either the image carrier or the paper carrier is not less than 50 percent and not more than 90 percent.

Cleaning unit and image forming apparatus having multiple cleaning blades

Cleaning unit, process cartridge, and image forming apparatus

An image forming apparatus for forming an electrostatic latent image on an electrophotographic photosensitive member, developing the electrostatic latent image and forming a developed image, and transferring the developed image to a recording medium to thereby form an image, the image forming apparatus including, a temperature sensor for detecting temperature in the image forming apparatus, and a controller for controlling a printing speed for forming the image so as to be reduced when the temperature detected by the temperature sensor is a predetermined temperature T or higher.

System for managing temperature in an image forming apparatus by controlling printing speed

An image forming apparatus includes a photosensitive member drum, a charging device for charging the photosensitive member drum, an image exposure device for image-exposing the photosensitive member drum, and an electric charge erasing device for erasing an electric charge outside an image-exposing area of the photosensitive member drum, wherein the electric charge erasing device is provided with a light emitting element and an optical element for lowering an amount of light which is incident on a border between the image-exposing area and an outside area thereof from the light emitting element.

Growing community of inventors

Sagamihara, Japan

Hiroya Hirose