Sharp Kabushiki Kaisha Corporation

Syouichi Fujita

Hirofumi Sakita

Kouichi Takenouchi

Hideji Saiko

Masato Asanuma

Itaru Kawabata

Hiroo Naoi

Motoyuki Itoyama

Mitsuhiro Murata

Yasuyuki Ishiguro

Mitsuru Tokuyama

Toshio Nishino

Hiroshi Kawamoto

Susumu Murakami

Masanobu Deguchi

Masatsugu Nakamura

Takahiko Kimura

Yasutaka Maeda

Takeshi Wakabayashi

Toshiaki Ino

Jitsuo Masuda

Minoru Tomiyori

Hiroshi Kawahito

Yoshiaki Sanada

Hideyuki Nishimura

Naotaka Funayama

Yasuhiro Nishimura

Takahiro Bito

Yoshiki Ichikawa

Tadayuki Sawai

Shinichi Azumi

Teruhiko Noguchi

Yuichi Kazaki

Atsushi Kurimoto

Kouji Shinkawa

Eiji Sato

Makoto Uehara

Seiichi Kizu

Yukihisa Imaue

Ken Yamagishi

Toshiaki Fujisawa

Masaya Fujitani

Keizo Kitamura

Masahiro Tsuji

Shuichi Morikuni

Takao Hiroyasu

Tao Ou

Fumito Mizoguti

Shintarou Hatano

Tatsuya Itou

A toner conveying member is a member with a shaft and a screw around a longitudinal non-end portion (i.e., a central portion) of the shaft integrally molded with resin, and also includes a metal pipe. The metal pipe includes a surrounding portion provided around an end portion of the shaft where the screw is not provided, and a buried portion buried in at least a portion of the screw and extended from the surrounding portion.

Toner conveying member for reducing bending of same, developing device, and image forming apparatus

There is provided an image stabilizing apparatus which is capable of keeping a toner concentration and a printing density constant when toner consumption is small, and further which is systematically simple. The image stabilizing apparatus comprises a control portion for controlling a toner replenishment amount in a toner replenishing apparatus depending on a toner concentration detected by a toner concentration sensor and a print coverage of a document detected by a print coverage detecting portion, and controlling, when the print coverage of the document detected by the print coverage detecting portion is less than a predetermined value and such documents continue, so as to discharge a predetermined amount of toner to the image bearing member by developing forcibly, and then replenish the same amount of toner as the predetermined amount by the toner replenishing apparatus.

Image stabilizing apparatus and image forming apparatus

There is provided a charging apparatus which has high durability and suffers from no rust etc. and of which controllability of charged potential of a photoreceptor is hardly impaired even with a some amount of contaminants such as a toner so that control of charged potential of a photoreceptor can be stably carried out to fall in an appropriate range over a long period of time, and moreover which is inexpensive. A charging apparatus includes a needle electrode, a holding member, two cleaner members, a support member, a moving member, a shield case, and a grid electrode. A length in minor axis of a secondary aggregate of polytetrafluoroethylene contained in a polytetrafluoroethylene-containing nickel layer formed on a surface of the needle electrode is twice or less than a layer thickness of the nickel layer.

Charging apparatus and image forming apparatus

An image forming apparatus is provided which is capable of forming higher-quality images by detecting a toner concentration with higher accuracy to attain appropriate toner supply and image density. A value obtained by adding a correction value based on a temperature, humidity, a print coverage, or the like to a developer concentration adjustment value is set as a control voltage value Vc which is to be inputted to a toner concentration sensor, and an output value of the toner concentration sensor is detected for each of process speeds. A difference between the output value detected and a value at reference process speed is calculated and based on the difference, a correction value is further calculated. Such another calculation of the correction value with use of the output value detected allows for highly accurate correction.

Image forming apparatus with variable process speed

A charging apparatus having a corona electrode is provided which exhibits high durability against ozone and moisture in the air, which can charge a surface of a photoreceptor drum stably throughout the life of an image forming apparatus, and which can be manufactured at a low cost. In a charging apparatus including corona electrode having a flat plate section and a pointed projection section, a support member, a shield case, and a grid electrode, a coating layer including a material different from the material of the corona electrode is formed at least on part of the surface of pointed projections constituting the pointed projection section.

A needle electrode and a cleaning member are provided. A plurality of needles are arrayed upon the needle electrode in a straight line, and protrude towards a surface of a photoreceptor. The cleaning member is disposed movably along the array direction of the plurality of needles between the surface of the photoreceptor and the needle electrode. When the cleaning member moves, the tip portion of each of the plurality of needles in the arranged order, after having been embedded from the surface of the cleaning member into its interior, then exits to the exterior of the cleaning member.

Electrification device, and image forming apparatus

A reference developing image is formed on a photoreceptor drum under an image forming condition measured in advance, and the density of this reference developing image is detected. A development bias voltage is corrected based on the detection result, and when a correction value of the development bias voltage exceeds a predetermined range, a reference output voltage of an ATC sensor for detecting the density of toner in a developing device is corrected based on the detected value of humidity around the developing device, the frequency of use of the apparatus, and the agitation stress of developer.

Image forming method and image forming device

A device has a process cartridge that includes a main cartridge accommodating a photosensitive body and a toner cartridge for use in replenis`hing toner as a precondition, is to precisely judge the service life of a photosensitive body and replacement timing of a main cartridge. Whether a predetermined condition is satisfied or not is judged with reference to a recording sheets count value G, a total operation time Tt and a toner cartridge related operation time Tx of the photosensitive drum, and a toner replenishing time Ts. In cases where a predetermined condition is satisfied, a message is displayed to urge the user to replace the process cartridge or the toner cartridge. When the toner is used up, the recording operation is inhibited, and an instruction to replace the process cartridge or the toner cartridge is displayed. Consequently, it is possible to accurately replace the photosensitive drum and toner cartridge at their respective adequate replacement timings.

Image forming apparatus with detachable mounting process cartridge

In an image-forming section, a communication device is attached to the top surface of a developing cartridge that is detachably attached to a developing device, and a main body side communication device is attached to a copying machine main body in a manner so as to face the top portion of the communication device. When a loading operation of the developing cartridge to the copying machine main body is carried out, the main body side communication device detects this operation, and sends an electric wave for an electrical supply to the developing cartridge. The communication device transmits individual information of the developing cartridge by means of radio waves, and the main body side communication device receives, demodulates and reads this information. Based upon the results thereof, it makes a judgment as to conformity and suitability of the developing cartridge, and displays the results of the judgement or gives a warning as to the results. Thus, it becomes possible to prevent an erroneous insertion of any unit to the image-forming apparatus main body by using a method with high reliability at low costs. It is possible to provide not only the developer supplying container, but also image-forming apparatus units serving as various units related to image-forming processes and an image-forming apparatus using such units.

Image-forming apparatus unit and image-forming apparatus

An image-forming apparatus is provided with: a rotatable photoreceptor; a charging device for charging the surface of the photoreceptor to a predetermined electric potential. A device for corona discharging, the charging device has a control electrode for controlling the quantity of corona ions that are allowed to reach the photoreceptor. A latent image forming device for forming an electrostatic latent image on the photoreceptor that has been charged by the charging device by use of light irradiation. There is a developing device for developing the electrostatic latent image by using a developer; and a control voltage supply device for supplying a control voltage to the control electrode and for switching the control voltage to a plurality of stages from a low-voltage side to a high-voltage side until the surface electric potential of the photoreceptor has risen to a predetermined electric potential. This image-forming apparatus prevents carrier rise at the time of a rise of the photoreceptor surface electric potential.

Image-forming apparatus which forms images by using a developer

To solve problems that the amount of reuse toner increases with time recovery of reuse toner is efficiently achieved while forming an image of high quality. In a toner replenishing apparatus, toner recovered by a cleaning unit is conveyed via conveying device and contained in a recovery toner container. When an amount of the recovery toner exceeds a predetermined capacity of the recovery toner container, the recovery toner flows into a fresh toner container over an upper edge of a partition wall. Fresh toner and recovery toner are replenished to a developing unit via a fresh toner replenishing roller and a recovery toner replenishing roller, respectively, and the ratio between fresh toner and recovery toner is selected so that the fresh toner occupies a larger part than the recovery toner. This ratio is controlled on the basis of the cumulative rotation time of a photoconductor drum counted by a counting device.

Toner replenishing apparatus and image forming apparatus equipped with same

A developing unit and an image forming apparatus includes drive and control mechanisms for the conveyance of collected toner and fresh toner in an uncomplicated structure and an uncomplicated toner supplying roller structure for the reduction in manufacturing cost. Fresh toner and collected toner stored in housing parts of a toner housing are discharged from an outlet via openings formed in a partitioning member for forwarding to a developing section by a toner supplying roller disposed to confront the outlet. The toner supplying roller is provided in common to fresh toner and collected toner. The toner supplying roller includes a single rotary shaft and a plurality of composite members which are fit into the rotary shaft. Each of the composite members has a cylindrical hollow body and a cylindrical elastic body which is fit onto the outer peripheral surface of the hollow body. The composite members are disposed correspondingly to the housing parts.

Developing unit and image forming apparatus

A cleaning device comprises: a first conveying member disposed further upstream in the rotating direction of a photoconductor drum than a cleaning blade, and constructed to rotate in non-contacting relationship to the photoconductor drum to convey residual toner that was removed by the cleaning blade; a second conveying member disposed parallel to the first conveying member and constructed to rotate in non-contacting relationship to the first conveying member; a first bias power supply for applying to the first conveying member a bias voltage having a polarity opposite to the proper polarity of the developer applied for development; and a second bias power supply for applying to the second conveying member a bias voltage having the same polarity as the proper polarity.

Cleaning device with electrically biased conveying members for

In an image forming apparatus having a developing unit for developing an image using toner, a toner box for withholding the toner, and a toner transportation section for transporting the toner withheld in the toner box to the developing unit, the toner transportation section includes a transportation screw portion having formed a spiral blade section on its shaft, a pipe section for controlling a toner transportation route by covering the transportation screw portion of the toner transportation section, and a toner flow suppressing section for suppressing flow of the toner from a space between the transportation screw and pipe section. Consequently, a toner transportation opening formed near the transportation section can be closed, and therefore, the flowing of toner into the developing unit can be controlled or reduced by a simple and inexpensive arrangement.

Image forming apparatus having developer supply device

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

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Kashiba, Japan

Syouichi Fujita