Canon Kabushiki Kaisha

Kazumi Yamauchi

Hideaki Hasegawa

Norihito Naito

Kazushige Sakurai

Nobuo Oshima

Katsuichi Abe

Yasunao Otomo

Naoki Fukushima

Atsushi Toda

Hiroshi Sato

Naoya Asanuma

Masahito Kato

Yosuke Kishi

Kenta Shibukawa

Yoshihiro Ogawa

Hiroaki Ogata

Hiroki Kisu

Tomomi Kakeshita

Koichi Suwa

Taku Watanabe

Michihito Yamazaki

Erika Asano

Tadashi Onimura

Eiji Funabashi

A control portion executes: a step of calculating a surface potential of an image bearing member charged by a charging member, to which a predetermined voltage is applied, and exposed to light by a predetermined exposure amount on the basis of a discharge start voltage between a measurement member and the image bearing member and calculating a correction value from a difference between a target value and calculated surface potential of the image bearing member; a step of correcting calculated surface potential of the image bearing member on the basis of the correction value; and a step of controlling at least one of the voltage applied to the charging member and an exposure amount of the exposure apparatus on the basis of the corrected surface potential of the image bearing member so that the surface potential of the image bearing member reaches the target value.

Image forming apparatus controlling surface potential of image bearing member

A developer container includes: a housing chamberwhich includes an openingand which houses developer; a stirring memberwhich includes a sheet-like stirring portionand a rotary shaftto which the stirring portionis attached; and a first electrodeand a second electrodewhich are used to detect an amount of the developer and which are arranged with an interval therebetween, wherein an area Xbetween the first electrodeand the second electrodein the housing chamberis positioned below the rotary shaftof the stirring member, and the sheet-like stirring portioncomes into contact with the area Xdue to rotation of the stirring member

Developer container, developing apparatus, process cartridge, apparatus main body, and image forming apparatus

A developer container includes: a housing chamberwhich includes an openingand which houses developer; a stirring memberwhich includes a sheet-like stirring portionand a rotary shaftto which the stirring portionis attached; and a first electrodeand a second electrodewhich are used to detect an amount of the developer and which are arranged with an interval therebetween, where in an area Xbetween the first electrodeand the second electrodein the housing chamberis positioned below the rotary shaftof the stirring member, and the sheet-like stirring portioncomes into contact with the area Xdue to rotation of the stirring member

A relationship between a light amount of an exposure portion and a surface potential according to a use amount, a first detection light amount corresponding to a prescribed surface potential in the relationship where a use amount of a photosensitive member is a first use amount and a second detection light amount corresponding to the prescribed surface potential in the relationship where the use amount of the photosensitive member is a second use amount, which is greater than the first use amount, are acquired. The exposure portion changes, as an electrostatic image forming light amount, a first image forming light amount representing a setting value under the first use amount to a second image forming light amount representing a setting value under the second use amount on the basis of a ratio of the first detection light amount to the second detection light amount.

Image forming apparatus

An image forming apparatus has a first image formation mode for forming an image on an image bearing member by using developer under a first predetermined image forming condition and a second image formation mode for forming an image on an image bearing member by using developer under a second image forming condition which is different from the first predetermined image forming condition and is set so that an amount of consumption of developer with respect to an identical image in the second image formation mode is smaller than that in the first image formation mode, the apparatus includes storing means for storing information on an amount of usage of the image bearing member, and control means for changing the second image forming condition in the second image formation mode depending on the information stored in the storing means.

Image forming apparatus, cartridge, and storing device mounted to the cartridge

An image forming apparatus to which a cartridge is mountable and which is operable to form images at different image formation speeds, wherein the cartridge includes a memory medium having a memory area for storing information relating to image forming conditions of process means corresponding to the image formation speeds, the image forming apparatus includes a control unit for setting the image forming conditions, wherein the control unit sets an image forming condition corresponding to the image formation speed on the basis of the image forming condition of the process means responding to the image formation speed.

Image forming apparatus to which a cartridge having a memory medium configured to store information-forming-condition information is attachable, such a cartridge, such a memory medium, and an image forming system comprising such a memory medium

A developing apparatus includes a rotatable, developer carrying body for carrying a one-component developer and a rotatable, agitating member for agitating the one-component developer. The one-component developer is magnetic toner at least containing a bonding resin and magnetic iron oxide. When wettability of the magnetic toner relative to a mixture solution of methanol and water is measured at the transmittance of light having a wavelength of 780 nm, a methanol concentration at the transmittance of 80% is within the range of 45 to 65 volume %, and wherein 0.1&#x2266;b/a&#x2266;0.2 is established where a (rps) denotes the rotation speed of the developer carrying body, and b (rps) denotes the rotation speed of the agitating member.

Developing apparatus including agitating member

A developing blade member for regulating a thickness of a layer of a developer on a peripheral surface of a rotatable developing roller enclosing a magnet roller, wherein a scraper for scraping the developer toward longitudinally inside of the developing roller is provided at a longitudinal end of the developing roller, the developing blade member including an elastic member for regulating the thickness of the layer of the developer on the peripheral surface of the developing roller; a metal plate for supporting the elastic member; a projection projecting toward the developing roller, the projection being provided at each of longitudinal ends of the metal plate, wherein an inside end of the projection, with respect to the longitudinal direction of the developing roller, is disposed inside of an inside end of the scraper and in a non-image-formation region.

Developing blade and device and process cartridge

In an image forming apparatus that is capable of forming an image in a plurality of image forming modes that correspond to frequencies of developing bias, a voltage value that reflects the image forming mode and amount of remaining toner is corrected using a correction quantity that conforms to the image forming mode.

Image forming apparatus and method of sensing amount of remaining developer in image forming apparatus

An image forming apparatus has a cartridge detachably mounted thereon, having unitized as one piece, one or more of a photosensitive body on which an electrostatic latent image is formed, a charging device for charging the photosensitive body, and a developing device for developing the electrostatic latent image formed on the photosensitive body and including a storage medium capable of storing electronic information, an exposing device for exposing the photosensitive body, and a device for detecting a used amount of the cartridge. The storage medium has information stored in advance for determining an exposure condition specific to each cartridge and has an area for writing used amount information of the cartridge detected by the detecting device, and performs control for changing the exposure condition of the photosensitive body based on the information for determining the exposure conditions and the used amount information.

Image forming apparatus, cartridge, image forming system and storage medium

During the changeover of image resolution to 600 dpi and 1200 dpi, potential setting is controlled in conformity with the individual information of a process cartridge and the used amount of a photosensitive drum. The individual information is information regarding the manufacturing lots or the kinds of the process cartridge, a developer, the photosensitive drum, a charging roller for acting on the photosensitive drum, a developing apparatus, a cleaning apparatus, and a functional member of the charging roller.

Electrophotographic image forming apparatus and process cartridge

An electrophotographic apparatus is provided having an electrophotographic photosensitive member and an exposure device for forming a static latent image on the electrophotographic photosensitive member surface by scanning with an exposure beam based on an image information. The spot diameter of the exposure beam is 2.5 times or more the size of one pixel of an image picture formed by the electrophotographic apparatus. The electrophotographic photosensitive member has the Fischer hardness of 240 Ns/mm or more in its surface, and the NESA sensitivity of 2000 V&middot;cm /&mgr;J or more, and is provided with an electric charge generating layer and an electric charge transportation layer 30 &mgr;m or less thick.

Electrophotographic apparatus, process cartridge, and electrophotographic photosensitive member

An object of the present invention is to provide an electrophotographic apparatus that has a photosensitive body, a charging member, provided to be capable of contacting with the photosensitive body, for charging the photosensitive body, an oscillating voltage being applied to the charging member, and exposing device for exposing the photosensitive body charged by the charging member, by an exposure beam based on image information to form an electrostatic image, wherein when a spot ratio which is a ratio of a spot diameter of the exposure beam to a size of one pixel of the electrostatic image is represented by &agr;, a pixel density of the electrostatic image is represented by R (dot/mm), a process speed of the photosensitive body is represented by V (mm/sec), a frequency of the oscillating voltage is represented by f (Hz) and a NESA sensitivity of the photosensitive body is represented by &ggr;(V&middot;cm /&mgr;m), 2.5&lE;&agr;, 4.2&lE;R&times;V/f&lE;7.0, and 2,000&lE;&ggr; are satisfied.

Electrophotographic apparatus

An image forming apparatus for forming images on a recording material includes an electrophotosensitive member. A developing devices develops a latent image formed on the electrophotosensitive member by using a developing agent contained in a container. A memory stores information with respect to an amount of consumption of the developing agent. A computing device computes a number of printable recording materials in accordance with the information, with respect to the amount of consumption of the developing agent, stored in the memory and a consumption rate information of the developing agent. An information output device outputs information of the number of printable recording material computed by the computing device.

Image forming apparatus, and a cartridge having a developer container detachably mountable on such apparatus

An image forming apparatus includes a photosensitive member, a charging device for charging the photosensitive member, an exposing device for exposing a light including image information to the photosensitive member, and a developing device for supplying a toner to an electrostatic latent image formed on said photosensitive member. The developing means is held by a cartridge removably mountable on a main body of the image forming apparatus. The cartridge includes a memory for memorizing an amount of use of the cartridge, wherein a charging amount of the toner caused by friction in the cartridge when the amount of use of the cartridge is in an initial state is smaller than that when the amount of use of said cartridge is not in an initial state. A judging device compares the amount of use of the cartridge with a predetermined value showing a condition that the amount of use of the cartridge is in the initial state. A control device controls operating parameters relating to at least one of the charging device, the exposing device, and the developing device, in accordance with a compared result of the judging device, so as to prevent thinning of an image line width until the amount of use of the cartridge reaches the predetermined value. The control device changes the operating parameters until the amount of use of the cartridge reaches the predetermined value, and sets the operating parameters to be constant after the amount of use of the cartridge reaches the predetermined value.

Growing community of inventors

Shizuoka, Japan

Kazumi Yamauchi