Ricoh Company, Ltd.

Hitachi Koki Co., Ltd.

Hitachi, Ltd.

Ricoh Printing Systems, Ltd.

Hitachi Printing Solutions, Ltd.

Other

Hiroyuki Mabuchi

Yukio Otome

Teruaki Mitsuya

Hiroshi Kikuchi

Hideki Kimura

Tadashi Ogawa

Junichi Terai

Seiji Maruo

Koji Kato

Masayoshi Ishii

Takao Umeda

Hiroaki Okamoto

Shinichi Akatsu

Hisao Okada

Masayasu Anzai

Shinya Kobayashi

Keisuke Kubota

Toru Miyasaka

Kenichi Ito

Takashi Suzuki

Nobuyoshi Hoshi

Yasuo Takuma

Akitomo Kuwabara

Masato Miwa

Masashi Nakayama

Hisayoshi Kato

Hirobumi Ooyoshi

Akira Fujimori

Sho Sawahata

Masayoshi Nakayama

Kazunori Suzuki

Shunichi Oohara

Tsuneaki Kawanishi

Tsukasa Onose

Yasuo Kikuchi

Akihiko Yamazaki

Ryuuichi Shimizu

Kenji Asuwa

Akio Tsujita

Mieko Ishii

Tomio Sugaya

Kazutoshi Obara

Takashi Rokutanda

Katsuya Kawai

Katsuya Akiba

Yoshihiro Gunji

Yosuke Saito

Kozi Kato

Hui Cheng

Yousuke Saito

Shinji Asai

A developing device includes a developer bearer, a developer regulator, a casing including an opposing face to oppose the developer bearer upstream from a developing range in a direction of rotation of the developer bearer, and first, second, and third seals. The first seal includes a first end secured to the casing and a second end to contact a latent image bearer upstream from the developing range in a direction of rotation of the latent image bearer. The second seal includes a first end secured to the opposing face of the casing, and a second end to contact the first seal upstream from the developing range. The third seal includes a first end secured to the opposing face of the casing, and a second end to contact developer on the developer bearer between the developer regulator and the developing range in the direction of rotation of the developer bearer.

Developing device, and process cartridge and image forming apparatus incorporating same

A developing device to develop a latent image on a rotatable image bearer includes an upstream developing roller disposed opposite the image bearer at a first developing position, and a downstream developing roller disposed adjacent to and downstream from the upstream developing roller in a direction of rotation of the image bearer, disposed opposite the image bearer at a second developing position. Each of the upstream developing roller and the downstream developing roller has a most approachable surface that approaches closest to the image bearer and a most withdrawn surface that withdraws farthest from the image bearer. In a state in which a reference surface point of the image bearer is disposed opposite the most approachable surface of the upstream developing roller at the first developing position, the reference surface point opposes the most withdrawn surface of the downstream developing roller at the second developing position.

Developing device, process cartridge, and image forming apparatus including same

An image forming apparatus includes a removable unit to be removably installed in the image forming apparatus, having a unit-side opening, a connectable device having an apparatus-side opening to be connected to the unit-side opening to send developer from one of the removable unit and the connectable device to the other, a receptacle disposed below the unit-side opening and the apparatus-side opening to receive and store developer dropping from above, and a drawer unit to be retractably drawn out from the image forming apparatus. The receptacle is united with the drawer unit to be drawn out from the image forming apparatus together with the drawer unit.

Image forming apparatus with removable unit and a connectable device to connect to the removable unit

A developing unit includes a developer bearer to bear developer on a surface thereof, first and second developer conveyors each having a spiral blade mounted on a rotary shaft thereof parallel to a rotary axis of the developer bearer to convey developer in opposite directions to each other. A developer drain hole is provided at a given height in a side wall of a second developer conveyance channel to face a communication opening across the second developer conveyor. The first developer conveyor rotates in a direction with its spiral blade rising between the rotary shaft of the first developer conveyor and the communication opening. Rotational phases of the first developer conveyor and the second developer conveyor are fixed and synchronized with each other to weaken momentum of developer flow generated by the first developer conveyor toward the developer drain hole via the second developer conveyor.

Developing unit, process cartridge, and image forming apparatus

A toner bottle driving device control method includes driving one of multiple toner bottle driving devices connected to a single toner container at a time, detecting abnormality of a toner bottle driving device being driven, determining a first abnormality phase of the toner bottle driving device being driven when a number of times the abnormality is detected exceeds a threshold, inhibiting the toner bottle driving device being in the first abnormality phase from driving until the first abnormality phase is resolved, driving a drivable toner bottle driving device containing a non-empty toner bottle when the toner bottle contained in the toner bottle driving device being driven is determined as empty, determining that the multiple toner bottle driving devices are in a second abnormality phase when each of the multiple toner bottle driving devices is determined as being in the first abnormality phase, and inhibiting image formation.

Toner bottle driving device control method and image forming apparatus

A powder supply device to supply powder to a supply destination includes a body, a single holder including multiple mounts on which multiple powder containers are removably mounted respectively, and a reservoir disposed in the body and below the single holder to store powder discharged from the multiple powder containers; and the single holder is removably attachable to the body of the powder supply device including the reservoir.

Powder supply device and image forming apparatus incorporating same

A powder feeding device includes a powder container, a feeding tank in communication with the powder container, a negative pressure room in communication with the feeding tank via a suction port communicating tube; an air suction device in communication with the negative pressure room via a negative pressure room communication tube; a suction port opening and closing unit that opens and closes the suction port communicating tube; a negative pressure room opening and closing unit that opens and closes of the negative pressure room communication tube; an output port opening and closing unit that opens and closes an output port of the feeding tank; and a controller that performs negative pressure generation control, powder supply control, and powder discharge control. Further, the controller simultaneously starts the negative pressure generation control and the powder discharge control.

Powder feeding device having negative pressure generation control and power discharge control and image forming apparatus

Powder feeding device having negative pressure generation control and powder discharge control and image forming apparatus

A transfer apparatus capable of suitably measuring the amount of electric charges transferred from a transfer member to a transfer body and performing a transfer process without degrading the image quality by supplying an amount of electric charges suitable for any type of transfer body onto which an toner image is to be transferred. The transfer apparatus in an image forming apparatus employing an electrophotographic method includes the transfer member electrically charging the transfer body; a charging unit for electrically charging a surface of the transfer member; and voltage sensors for measuring the voltage at each of an upstream area and a downstream area on the transfer member with respect to a transfer nip section of the transfer member.

Methods and apparatus for transferring a toner image via electrophotographics

An image forming apparatus has a photoconductive drum or belt supporting a toner image, a transfer member transferring the toner image onto a recording medium, a transportation device transporting the recording medium to between the photoconductor and the transfer member, a charger charging a surface of the transfer member to the anti-polarity of the electric charge of the toner image, a rotation drive unit rotating the transfer member to the same direction of the recording medium transportation, a contacting/removing unit that contacts the transfer member to the image supported member for printing and removes the transfer member from the image supported member when not printing, and a drive force transferring/blocking unit that transfers the drive force from the rotation drive unit to the transfer member before print starting-up and blocking the drive force during printing.

Image forming apparatus and tandem image forming apparatus

A transfer apparatus comprises a toner image supporting body and a corona transfer means, which are oppositely disposed, and a vibrating unit for exerting vibration force to the rear face of a toner supporting body, disposed opposite to the corona transfer means, wherein the vibrating unit has a cantilever structure for holding an end of a piezoelectric bimorph element in which a pair of piezoelectric bodies each having an electrode, are bonded to both sides of a conductive elastic member (a shim member). A protrusion portion is provided on the other end of the piezoelectric bimorph element.

Transfer apparatus, method of manufacturing the transfer apparatus and image forming apparatus using the transfer apparatus

A developer transporting amount controlling member that is used in a developing apparatus is disclosed. The developing apparatus includes a recording unit having a surface that sustains an electrostatic latent image and attracts a developer, a developer transporting unit that transports the developer, and a developing unit that guides the developer to the recording unit. The recording unit, the developer transporting unit, and the developing unit have rotational center axes that are parallel to each other. The developer transporting amount controlling member includes a magnetic part and a nonmagnetic part that is harder than the magnetic part and is fixed to the developing apparatus such that a portion of the nonmagnetic part is disposed closest to the developing unit.

Developer transporting amount controlling member, developing apparatus, imaging apparatus, and method for exchanging developing unit

An electrophotographic apparatus includes: a photoconductor; and two developing rollers facing the photoconductor. A developer fed out from between the two developing rollers is supplied to the photoconductor by the two developing rollers to form a toner image on the photoconductor. The developer includes a carrier having a volume-average particle size smaller than 70 &#x3bc;m and a volume resistivity not lower than 10&#x3a9;&#xb7;cm. A volume ratio of the carrier in a facing portion between the photoconductor and the developing rollers is not lower than 30% and not higher than 46%.

Developing device and electrophotographic apparatus using the same

A developing device is provided with a developer accommodating vessel accommodating developer having as primary components a nonmagnetic toner and magnetic particles referred to as a carrier. The carrier is composed of a magnetic material as a core material that is uniformly covered with an insulating synthetic resin. The toner is mixed with the carrier at a weight ratio to the overall weight of the developer of 3-10%. The carrier has an average particle size of 65 &#x3bc;m or less and a saturation magnetization of at least 70 emu/g. The developing device includes a developing roller and a sleeve roller that rotates about the developing roller. The surface of the sleeve roller is processed with metal shot to achieve a surface roughness of 0.45-1.08 times the average particle size of the carrier, or more specifically a roughness Rz of about 30 &#x3bc;m.

Developing device using developer of particular properties suitable therefore

A developing apparatus characterized in being constituted to satisfy Equation (1) shown below when an amount of a developer carried by 1 pitch of a carrying member of an auger or the like is designated by notation W(g), a toner amount supplied by 1 pitch during a time period in which the developer carried by 1 pitch passes a supply region of a toner supply roller is designated by notation M(g), a toner concentration of the developer detected by a toner concentration sensor is designated by notation Tc (%), and a mixing limit toner concentration is designated by notation Tmax (%)(&#xd7;()/()&#x2266;max/100. &#x2003;&#x2003;(1)

Developing apparatus and electrostatic recording apparatus using the same

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Kanagawa, Japan

Hiroyuki Mabuchi