Sharp Kabushiki Kaisha Corporation

Hiroshi Kawamoto

Yasutaka Maeda

Jitsuo Masuda

Masayasu Narimatsu

Syouichi Fujita

Hideyuki Nishimura

Yuichi Kazaki

Makoto Uehara

Naoki Fukudo

Takashi Kubo

Yasuyuki Ishiguro

Takahiko Kimura

Kazuyuki Ohnishi

Masahiro Sakai

Katsuhiro Nagayama

Takeshi Wakabayashi

Toshiaki Ino

Takashi Kitagawa

Hiroshi Kawahito

Toshio Nishino

Hidetoshi Kaneko

Yoshiaki Masuda

Kenichi Shiraishi

Naotaka Funayama

Itaru Kawabata

Hiroaki Yoshida

Yoshiki Ichikawa

Hirofumi Sakita

Koichi Moriyama

Yuichiro Takesue

Mamoru Fujii

Ken Yamagishi

Masahiro Tsuji

Takao Hiroyasu

Yuka Sakagami

Tao Ou

Fumito Mizoguti

Shintarou Hatano

Masakatsu Hayashi

Hiroaki Takeshima

Akihiko Kumagai

An image forming apparatus and a method for cleaning a photoreceptor are realized that allow cleaning a surface of the photoreceptor to eliminate foreign substances adhering thereto, without using a special abrasive sheet. A recording sheet is fed and brought into contact with photoreceptors of all photoreceptor drums. The recording sheet is stopped by causing the vicinity of a rear end of the recording sheet to be sandwiched between a pair of registration rollers. Then, the photoreceptor drums are rotated. By this way, the cleaning is carried out to the photoreceptor.

Image forming apparatus capable of cleaning a photoreceptor, method for cleaning a photoreceptor, and computer program for causing an image forming apparatus to clean a photoreceptor

In case of a developing density correction based on a test image (patch image) density, normally, the developing density is carried out in a short period of time by correction (&#x3b3; correction) of a developing bias and a grid voltage (S). When a correction amount of the &#x3b3; correction exceeds an ordinary range, the &#x3b3; correction (S) and adjustment of toner concentration (magnetic permeability reference value) (S) are carried out in combination. Furthermore, when the toner concentration is changed, the setting of a correction reference of the &#x3b3; correction (&#x3b3; correction TBL) and correction timing of the &#x3b3; correction are accordingly changed (S, S). Therefore, in the developing density correction based on the test image density in the developing device using binary developer, it is possible to carry out the developing density correction, which is carried out in a short time, and whose correction width is wide, while maintaining the accuracy of a developing density adjustment.

Developing device, image forming device equipped therewith, and developing density adjusting method

An object of the invention is to make an exact judgment on suitability of a replaceable component such as a toner supplying container with use of an existing mechanism of an image forming apparatus, without additionally providing a data storage component designed for a consumable product which is detachably attached to the apparatus, or a data reading component to be placed in the image forming apparatus main body. In an incorporated control section, a specific part of a replaceable component, which is placed on an original platform prior to being loaded into the apparatus, is optically scanned to read image information, and, based on the reading result, whether or not the replaceable component is suitable for the image forming apparatus is judged.

Image forming apparatus and method for determining suitability of replaceable component

A facsimile provided with a easily detachable scanner disclosed. When a button provided in a panel of a facsimile body F is pushed, lower a right end R of a release lever is depressed, and the release lever is turned on a pivot C to raise its left end L, thereby boosting a bottom of the scanner S. In consequence thereof, the scanner S is ached from the facsimile body F.

Facsimile

The object of this invention is to provide an image forming apparatus capable of preventing decrease in image density at a rear end part of an image. A change in waveform in sensor outputs which is produced when a toner patch image is read by an optical sensor used for the process control is detected. The difference (Vg&minus;Vd) between grid voltage Vg and development bias voltage Vd is changed only between a target value of 300 V corresponding to low-output side threshold value Va and a target value of 100 V corresponding to high-output side threshold value Vb according to the sensor output deflection &Dgr;V so that the difference (Vg&minus;Vd) decreases as the image loss level increases. The difference between the grid voltage Vg and the development bias voltage Vd is set so as to prevent the image loss in the rear end part of an image.

Image forming apparatus with automatic density compensation

A developing device having a reduced size in the horizontal direction and in which a developing agent is transported with stirring along a circulating route inside a developing tank to effectively mix newly added toner therewith and stir the mixture. A developing tank for storing developing agent therein is horizontally divided with a partition member thereby providing an upper chamber and a lower chamber. A developer roller and a stirring roller are disposed in the lower chamber. Two screw rollers are disposed in the upper chamber. An inlet opening is formed between an end of the partition member and a regulating member for restricting a layer if the developing agent adsorbed to the developing roller. A developing agent removed by the restricting member is fed through an inlet opening to the screw rollers in the upper chamber. The developing agent is mixed with fresh toner supplied through a supply inlet and transported with being stirred by the screw roller in its axial direction. Then, the developing agent is transferred to the screw roller disposed parallel to the screw roller and it is further transported and returned to the stirring roller in the lower chamber through a return port provided opposite to the screw roller. The compact construction of the developing device is realized by arranging screw rollers for stirring and transporting toner in the upper chamber.

Developing device having a reduced width in the horizontal direction

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

The present invention provides a compact electrophotographic device in which the gap between a screen and a photosensitive body can be kept uniform throughout the screen, no fogging is caused on a copied imaged, no wasteful space is around the photosensitive body, color contaminations are completely prevented and the quality of a color copied image is improved.

Electrophotographic apparatus with reduced contamination from toner

An image adjusting apparatus being provided in a copying machine capable of performing a copy of an original by using a photosensitive body in two or more copying modes, includes a unit for sensing a toner density of an image formed on the photosensitive body, a unit for deriving a function in accordance with each of the two or more copying modes if a control voltage influencing the toner density is changed, and a unit for setting the control voltage to be a voltage value obtained based on a predetermined reference toner density and the function derived by the deriving unit. The function stands for a relation between the changed control voltage and the toner density sensed by the sensing unit.

Image adjusting apparatus having a controlled the voltage applied to the

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Tenri, Japan

Hiroshi Kawamoto