Sharp Kabushiki Kaisha Corporation

Hideyuki Nishimura

Yasutaka Maeda

Katsuhiro Nagayama

Taisuke Kamimura

Tsuyoshi Miyamoto

Natsuko Tanaka

Yukihiko Ueno

Yuichi Kazaki

Hitoshi Nagahama

Yoichi Shimazawa

Hirofumi Sakita

Kohji Shinkawa

Hiroshi Kawamoto

Takeshi Murata

Hirokazu Izumi

Kyouichi Takata

Keiko Yutani

Hisaaki Kobayashi

Kazuyuki Ohnishi

Hideo Matsuda

Takafumi Nagai

Hiroshi Kawahito

Syouichi Fujita

Masato Tokishige

Itaru Kawabata

Yoshiki Ichikawa

Tokiyuki Okano

Kiyoshi Inamoto

Satoshi Machino

Koichi Moriyama

Kazunori Sohda

Masahiro Tsuji

Takao Hiroyasu

Koji Shinkawa

Shouichi Fujita

Fumito Mizoguti

Shintarou Hatano

Tuyoshi Miyamoto

An image forming apparatus capable of selecting a toner cartridge from a plurality of toner cartridges containing toner of an identical color preferentially without interrupting an image forming action of the apparatus. When a toner density of the toner in a developer container becomes low, a control section drives a toner supply section in response to information on the remaining amount of the toner contained in the toner cartridges, so that the toner may be supplied from the toner cartridge having the least remaining amount.

Image forming apparatus for supplying toner from one of a plurality of toner cartridges

The image forming apparatus according to the present invention detects the amount of remaining toner by using (i) the result of calculation carried out by a toner supply amount calculation section based on an accumulated rotational time measurement section in a region where the amount of remaining toner is not less than a predetermined amount and toner supply is stabilized, (ii) the result of calculation carried out by a pixel count section in a region where the amount of remaining toner gets small and the amount of toner supply gets uneven, and (iii) the result of ATC carried out by a toner density control section. As a result, it is possible to exactly detect the amount of remaining toner without providing a special remaining toner detection device.

Image forming apparatus and method for detecting amount of remaining toner

An equipment unit such as a toner cartridge detachably equipped to an image forming device has a product information related to the equipment unit recorded on the outer surface thereof using an organic pigment having infrared reflectiveness that cannot be observed normally with the naked eye.

Equipment unit with imperceptible information recorded thereon being used with an image forming device and an image forming device comprising the same

An image forming devicecomprises an electrophotographic processing unitequipped with a developerincluding a developing agent containing black toner having infrared reflectiveness, and forms an image having infrared reflective property. The image forming devicefurther comprises a detectorfor detecting whether the formed toner image has infrared reflective property or not and a control unit for controlling each unit based on the result of detection by the detectorso as to form a black image having infrared reflective property in a reliable manner.

Image forming device, toner and copy

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

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

An electrophotographic image forming apparatus for transferring a visible toner image formed on a photoconductive body onto an intermediate transfer body primarily and transferring the toner image transferred on the intermediate body onto a paper secondarily is disclosed. In the electrophotographic image forming apparatus, the toner remaining on the photoconductive body is removed by a first cleaner blade after the primary transfer, and the toner remaining on the intermediate transfer body is removed by a second cleaner blade after the secondary transfer. A contact pressure of the second cleaner blade to be applied to the intermediate transfer body is set to be larger than a contact pressure of the first cleaner blade to be applied to the photoconductive body.

Image forming apparatus having intermediate transfer member

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

A transfer unit including: a transfer belt onto which toner images are formed; a backup roller on which said transfer belt is applied, the metallic surface of said backup roller being coated with a dielectric film; a metallic transfer roller that is disposed opposite to said backup roller across said transfer belt and to which a predetermined transfer voltage is applied, said transfer roller pressing copy paper against said backup roller with said transfer belt placed therebetween so that said toner images formed on said transfer belt are transferred onto said copy paper to be transported between said transfer roller and said transfer belt; and a back plate that is located in the vicinity of said backup roller and that contacts the back surface of said transfer belt, whereby an electric field for transferring a toner image by a low transfer voltage can be created, thereby preventing the transfer belt from dielectric breakdown.

Transfer unit

An electrophotographic copying apparatus comprises a photosensitive member (4) exposed by light reflected from an original to form an image of the original thereon, mechanism (13) for developing the image on the photosensitive member with toner (9, 10, 11, 12) to produce a toner image corresponding the image mechanism (24) for transferring the toner image onto a transfer material, mechanism (26) for fixing the toner image transferred on the transfer material, mechanism (27) for producing a signal which represents that high surface glossiness of the image copy is required, and mechanism (31, 32) for feeding the transfer material in a first path when the signal is produced, the transfer material being fixed fully, and for feeding the transfer material in a second path shorter than the first path when the signal is not produced.

Electrophotographic copying apparatus

A cleaning structure of an image forming device comprises an image retainer, a cleaning blade supported to touch a moving surface of the image retainer, a cleaning roller supported to touch the moving surface of the image retainer in a position downstream from the position of the cleaning blade. The cleaning roller comprises a roller shaft, a roller base layer and a fluorocarbon polymer layer which is excellent in noncohesiveness and slip property.

Cleaning structure for moving image retainer for use in an image forming

A method of cleaning a photosensitive member in an electrophotographic apparatus in which an electrophotographic operation is performed by charging the photosensitive member with a predetermined voltage, exposing the charged photosensitive member so as to form a latent image thereon and developing the latent image by use of toner, includes the steps of charging the photosensitive member with a half tone level voltage which is smaller than the predetermined voltage, and developing the charged photosensitive member by use of toner without exposing the charged photosensitive member, so as to form a uniform half tone toner image thereon. The cleaning method also includes the step of scraping off the toner of the uniform half tone toner image from the photosensitive member by a blade abutting thereto.

Electrophotographic apparatus and method of cleaning the same

A transfer roller device for transferring onto a copy paper sheet a full color toner image formed on an intermediate transfer belt. A rear-surface electrode roller disposed at the opposite side to a transfer roller with the intermediate transfer belt positioned in between, is divided into a plurality of cylinder members, and at least one of the cylinder members corresponding to the size of a copy paper sheet is separately connected to ground. With the arrangement, occurrence of an excess current through a portion of the intermediate transfer belt carrying no copy paper sheet thereon is eliminated, thereby preventing a filming phenomenon. In another arrangement, a plurality of rear-surface electrode rollers are disposed at respective positions associated with a plurality of respective copying speeds which are set according to copy paper sheets. Thus, a voltage to be applied between the transfer roller and the rear-surface electrode roller is maintained constant regardless of different copying speeds.

Transfer roller device

A copying apparatus in which a screen for improving gradation characteristics of a copied image can be retractably projected into an optical path, including a device for setting, when the screen is placed in the optical path and retracted from the optical path, a developing voltage to a first value and a second value, respectively such that the first value is lower than the second value.

Copying apparatus with moveable screen and method

A copying apparatus having a prescanning function for obtaining density data to adjust copy parameters includes a correction function which eliminates the data obtained from a portion of a predetermined color, from the density data detected on a prescanning process. The density data can be restricted within a predetermined range. The predetermined range can be easily set by the user.

Growing community of inventors

Yamatokoriyama, Japan

Hideyuki Nishimura