Ricoh Company, Ltd.

Jun Yura

Takashi Fujita

Atsushi Nakafuji

Hirokazu Ikenoue

Hisashi Kikuchi

Toshihiko Baba

Shigeo Kurotaka

Hideki Kosugi

Katsuhiro Echigo

Hiroyuki Sugiyama

Masaki Sukesako

Hironobu Takeshita

Hiroshi Nakai

Hirokatsu Suzuki

Kiyoshi Ohshima

Kazumi Suzuki

Yukiko Iwasaki

Koichi Kato

Ichiro Kadota

Kei Yasutomi

Kazuaki Kamihara

Jun Shiori

Masahide Yamashita

Shigekazu Enoki

Takeshi Uchitani

Toshiyuki Kabata

Yasushi Koichi

Osamu Ariizumi

Kumiko Hatakeyama

Takuya Suganuma

Hiroki Ishii

Echigo Katsuhiro

Koji Suzuki

Shinya Tanaka

Shinji Aoki

Nobuo Kasahara

Yasunobu Shimizu

Kazuhito Kishi

Akio Kosuge

Hiromi Ogiyama

Emiko Shiraishi

Masato Iio

Ken Yoshida

Hiroyuki Shibaki

Naoyuki Ozaki

Tokuya Ojimi

Koichi Katoh

Tokuya Ohjimi

Masako Yoshii

Emiko Ishikawa

Eriko Konno

Ichiro Maeda

Ryota Kidera

Shogo Kezuka

Kohichi Katoh

Yasuhiko Taguchi

An image forming apparatus includes a fixing member, a pressing member, heat generators, temperature detectors, a power source, and a heat controller. The heat generators include a first heat generator and second heat generators corresponding to an imaged area and a blank area, respectively, of a recording medium. The heat controller controls a power source according to data provided by the temperature detectors, such that a heating area of the fixing member heated by one of the second heat generators located adjacent to the first heat generator acquires a temperature of T&#x2212;&#x394;T, where Tis a temperature corresponding to the imaged area higher than a temperature Tcorresponding to the blank area, and &#x394;T is a temperature lower than a difference between Tand T. The heat controller changes &#x394;T between when a first side thereof is printed upon duplex printing and upon single-sided printing.

Fixing device and image forming apparatus incorporating same

An image forming apparatus comprises an image information obtainer that obtains image information, a gradation sequence processor that applies multiple types of gradation sequence processing to the image information, and a toner image formation device that forms a toner image based on the image information. A fixing device is provided to fix the toner image onto a recording medium in a fixing process. A temperature controller is also provided to change a start-up temperature of the fixing device before the fixing process. The start-up temperature is changed in accordance with inclusion of a halftone process and a type of the gradation sequence processing applied to the image information.

Image forming apparatus capable of obtaining good fixed condition regardless of type of gradation sequence processing

An image forming apparatus includes an image bearing member to bear a latent image on a surface thereof, a developing unit to develop the latent image on the image bearing member with toner, a driving unit to drive the developing device, a storage unit to store a cumulative travel distance of the developing roller at predetermined timing, a total travel distance of the developing unit, and control conditions for the developing unit, a controller to obtain a difference between the total travel distance of the developing roller and the cumulative travel distance up to a predetermined point in time in image forming operation and to instruct intermittent printing in which continuous printing is limited to a certain number of pages in a predetermined time period when the difference is equal to or greater than a threshold travel distance, and an operation unit in which the control conditions are set.

Image forming apparatus

An image forming apparatus capable of continuous image formation on multiple pages includes an image bearer to bear an image, a latent image forming unit to form a latent image on the image bearer, a developing device to develop the latent image with toner, a temperature sensor to detect temperature inside the developing device or adjacent to the developing device, a controller to impose a limit on a quantity of pages in continuous image formation and cancel the limit according to a detection result generated by the temperature sensor, and a report unit to report time data indicating when the limit is imposed.

Disclosed is an image forming device including a fixing unit that fixes a first image to be fixed onto a sheet, the first image to be fixed being supported on the sheet, a target fixing temperature varying unit that varies a target fixing temperature during a time period in which a fixing process is performed, and a gradation processing unit that applies a gradation process to first image information. The target fixing temperature varying unit varies the target fixing temperature for the sheet of the recording medium to which the fixing process is applied, depending on presence or absence of a halftone process, and depending on a type of the gradation process to be utilized.

Image forming device

An image forming apparatus includes a developing device including a developing roller to bear a developing agent to develop a latent image formed on an image bearing member, a cooling device to reduce an internal temperature of the image forming apparatus, a controller to calculate a travel distance of the developing roller to control the cooling device, and a memory unit to store the total travel distance of the developing roller. The controller calculates the total travel distance of the developing roller every Y minutes in the last X minutes, and a difference between the latest total travel distance of the developing roller and the total travel distance stored Z minutes ago by the memory unit to obtain the total travel distance during Z minutes and operate the cooling device for W minutes after image forming operation where the difference is equal to or greater than a threshold value M.

Image forming apparatus including a controller to control a cooling device to cool the image forming apparatus

An image forming apparatus including a fixing unit configured to fix a not-yet-fixed image on a recording medium, includes a fixing target temperature changing part configured to change a fixing target temperature at a time of a fixing process; and a gradation processing part configured to carry out gradation processing on image information. For each sheet of a recording medium on which the fixing process is carried out, the fixing target temperature is changed based on whether halftone processing is carried out and a type of gradation processing to be used.

Image forming apparatus for fixing a not-yet-fixed image

A fixing apparatus includes a fixing member to be heated and a pressure-contacting member for pressure contacting the fixing member. The fixing apparatus directs and conveys a recording member through a nip formed between the fixing member and pressure applying member in such a manner that a toner image carried on a recording member contacts the fixing member in order to be fixed thereto with heat and pressure. The fixing apparatus is configured to direct a tip margin of the recording member toward the pressure applying member across a virtual linear extension line drawn from a downstream end to upstream end of the nip when only the tip margin exits from the nip. A fixing member side separation device may be separately provided from the surface of the fixing apparatus so as to separate the recording member exiting from the nip. A gap formed between the downstream end of the nip and the tip of the fixing member side separation device is set smaller than the width of the tip margin.

Sheet wrapping avoidable fixing apparatus and image forming apparatus

An image forming apparatus including a latent image carrier, a charger to evenly charge a surface of the latent image carrier, a writing device to irradiate a charged surface of the latent image carrier to form an electrostatic latent image, a writing device control unit to control the writing device, a developing device to develop the electrostatic latent image to form a toner image, a transfer device to transfer the toner image onto a transferred member, and a pre-transfer irradiating device to irradiate the charged surface of the latent image carrier during a period after development and before transfer. The writing device control unit controls the writing device based on a target image signal A and an image signal B output a single rotation of the latent image carrier after output of the target image signal A in a sub-scanning direction.

An apparatus and method for image fixing are disclosed. A fixing device includes a fixing member, a pressure member, a heater, and a pressure controller. The fixing member and the pressure member face with each other to form a nip. The heater heats a surface of the fixing member when the fixing member rotates. The pressure controller changes a pressure generated at the nip, according to an operation of the fixing device.

Apparatus and method for fixing an image

To provide an image bearing member protecting agent that includes at least a hydrophobic organic compound and an amphiphile organic compound. Preferred embodiments are that the hydrophobic organic compound is a hydrocarbon wax, and the hydrocarbon wax is at least a wax selected from normal paraffins, isoparaffins, and cycloparaffins; and that the amphiphile organic compound is an polyalcohol esterified compound including a nonionic surface active surfactant, and the nonionic surface active surfactant is an alkyl carboxylic acid represented by a structural formula, CHCOOH.

Protecting agent for image bearing member and production method therefor, protection layer forming apparatus, image forming method, image forming apparatus, and process cartridge

An image forming apparatus includes an image carrier, a charging unit including a charge member that is disposed facing the image carrier across a gap therebetween and charges the image carrier by using electrical discharge caused by applying thereto a voltage including an alternating current component superimposed on a direct current component, a latent image forming unit, a developing unit to supply toner for developing the latent image formed on the image carrier into a toner image and to collect residual toner remaining on the image carrier, a transfer unit, and a toner spreading member to spread toner on the image carrier and disposed upstream from the charging unit in a direction of movement of the image carrier and downstream from the transfer unit in the direction of movement of the image carrier.

Image forming apparatus including a cleaner-less image carrier cleaning system

An image forming apparatus includes a pseudo half tone processing unit that performs a pseudo half tone process on input image data to generate output image data. An exposure unit executes light modulation of a plurality of light emitting sources based on the output image data. The exposure unit performs writing in such a way that different numbers of light emitting sources are used when writing a character/line image and a picture image or a graphics image. The pseudo half tone processing unit performs pseudo half tone processes with different resolutions on a character/line image and a picture image or a graphics image based on the numbers of the light emitting sources to be used for the writing by the exposure unit.

Image forming apparatus and image forming method using pseudo half tone processing with different resolutions

An apparatus including and a method using a fixing device including a fixing member, a pressure member, a heater, and a pressure controller. The fixing member and the pressure member face with each other to form a nip. The heater heats a surface of the fixing member when the fixing member rotates. The pressure controller is configured to change a pressure generated at the nip, according to an operation of the fixing device.

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Kanagawa, Japan

Jun Yura