Patents by Inventor Hirofumi Sakita
Hirofumi Sakita has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).
-
Patent number: 7949265Abstract: A toner supply device for supplying toner to a developing device includes: a first toner supply portion for supplying toner to a developing hopper; a second toner supply portion for supplying the stored toner to the first toner supply portion; a first toner supply driver for driving the first toner supply portion; a first residual toner quantity detector for detecting the residual toner quantity in the first toner supply portion; a second toner supply driver for driving the second toner supply portion; a second residual toner quantity detector for detecting the residual toner quantity in the second toner supply portion; and a controller for controlling the drives of the first and second toner supply drivers by switching on and off the drives of the first and second toner supply drivers in accordance with the residual toner quantities detected by the first and second residual toner quantity detectors.Type: GrantFiled: August 1, 2008Date of Patent: May 24, 2011Assignee: Sharp Kabushiki KaishaInventors: Hirofumi Sakita, Takeshi Murata, Yoshinori Ohtsuka, Masaaki Ohtsuki
-
Patent number: 7738816Abstract: 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.Type: GrantFiled: September 11, 2006Date of Patent: June 15, 2010Assignee: Sharp Kabushiki KaishaInventors: Hirofumi Sakita, Hideyuki Nishimura, Hisaaki Kobayashi, Hirokazu Izumi
-
Patent number: 7619791Abstract: 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.Type: GrantFiled: March 2, 2004Date of Patent: November 17, 2009Assignee: Sharp Kabushiki KaishaInventors: Motoyuki Itoyama, Syouichi Fujita, Hirofumi Sakita, Shuichi Morikuni
-
Publication number: 20090047044Abstract: A toner supply device for supplying toner to a developing device includes: a first toner supply portion for supplying toner to a developing hopper; a second toner supply portion for supplying the stored toner to the first toner supply portion; a first toner supply driver for driving the first toner supply portion; a first residual toner quantity detector for detecting the residual toner quantity in the first toner supply portion; a second toner supply driver for driving the second toner supply portion; a second residual toner quantity detector for detecting the residual toner quantity in the second toner supply portion; and a controller for controlling the drives of the first and second toner supply drivers by switching on and off the drives of the first and second toner supply drivers in accordance with the residual toner quantities detected by the first and second residual toner quantity detectors.Type: ApplicationFiled: August 1, 2008Publication date: February 19, 2009Inventors: Hirofumi SAKITA, Takeshi Murata, Yoshinori Ohtsuka, Masaaki Ohtsuki
-
Patent number: 7415214Abstract: 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.Type: GrantFiled: August 21, 2006Date of Patent: August 19, 2008Assignee: Sharp Kabushiki KaishaInventors: Hirofumi Sakita, Hirokazu Izumi, Hideyuki Nishimura, Hisaaki Kobayashi
-
Publication number: 20070059015Abstract: Provided is a coverage monitor for monitoring a utilization scale of an MFP which forms an image on a sheet with color toner. The coverage monitor comprises: (i) a periodic coverage updating section for generating a periodic coverage which denotes a coverage from a certain time point, which is specified by an administrator of the MFP, to a present time, based on image data expressing the image; and (ii) a display control section for displaying the periodic coverage so that the administrator can visually confirm the coverage. The coverage monitor enables the administrator to easily comprehend the profit rate.Type: ApplicationFiled: July 28, 2006Publication date: March 15, 2007Applicant: Sharp Kabushiki KaishaInventors: Hirofumi Sakita, Hirokazu Izumi, Hideyuki Nishimura, Hisaaki Kobayashi
-
Publication number: 20070058996Abstract: 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.Type: ApplicationFiled: August 21, 2006Publication date: March 15, 2007Applicant: Sharp Kabushiki KaishaInventors: Hirofumi Sakita, Hirokazu Izumi, Hideyuki Nishimura, Hisaaki Kobayashi
-
Publication number: 20070058997Abstract: An image forming apparatus is provided, which is capable of using such a toner cartridge preferentially without interrupting an image forming action as is desired for an early use and as has a less toner remaining amount. When a toner density in a developer container to be supplied with the toner from either of two toner cartridges becomes low, a control section drives either of motors in response to toner remaining amount detection information which is information on the remaining amount of the toner contained in each of the toner cartridges, so that the toner may be supplied from the toner cartridge having the less toner remaining amount. Thus, the toner can be supplied to the developer container from the toner cartridge having the less toner remaining amount.Type: ApplicationFiled: September 11, 2006Publication date: March 15, 2007Applicant: Sharp Kabushiki KaishaInventors: Hirofumi Sakita, Hideyuki Nishimura, Hisaaki Kobayashi, Hirokazu Izumi
-
Publication number: 20060152775Abstract: 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.Type: ApplicationFiled: March 2, 2004Publication date: July 13, 2006Applicant: SHARP KABUSHIKI KAISHAInventors: Motoyuki Itoyama, Syouichi Fujita, Hirofumi Sakita, Shuichi Morikuni
-
Patent number: 6512896Abstract: 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 Tt1 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.Type: GrantFiled: May 25, 2001Date of Patent: January 28, 2003Assignee: Sharp Kabushiki KaishaInventors: Masato Asanuma, Kouichi Takenouchi, Hiroo Naoi, Syouichi Fujita, Hirofumi Sakita, Hideji Saiko
-
Publication number: 20010055493Abstract: The object of the present invention, employing a process cartridge that includes a main cartridge accommodating a photosensitive body and a toner cartridge for use in replenishing 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 Tt1 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.Type: ApplicationFiled: May 25, 2001Publication date: December 27, 2001Inventors: Masato Asanuma, Kouichi Takenouchi, Hiroo Naoi, Syouichi Fujita, Hirofumi Sakita, Hideji Saiko
-
Patent number: 6324351Abstract: 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.Type: GrantFiled: December 21, 1999Date of Patent: November 27, 2001Assignee: Sharp Kabushiki KaishaInventors: Atsushi Kurimoto, Syouichi Fujita, Hirofumi Sakita, Hideji Saiko
-
Patent number: 6311027Abstract: 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.Type: GrantFiled: January 4, 2000Date of Patent: October 30, 2001Assignee: Sharp Kabushiki KaishaInventors: Hirofumi Sakita, Syouichi Fujita, Hideji Saiko, Mitsuru Tokuyama, Masatsugu Nakamura, Hiroo Naoi, Kouichi Takenouchi
-
Patent number: 6226490Abstract: 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.Type: GrantFiled: July 23, 1999Date of Patent: May 1, 2001Assignee: Sharp Kabushiki KaishaInventors: Syouichi Fujita, Itaru Kawabata, Hideji Saiko, Hirofumi Sakita, Masato Asanuma, Kouichi Takenouchi, Yoshiaki Sanada, Yasuyuki Ishiguro
-
Patent number: 6167227Abstract: 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.Type: GrantFiled: October 19, 1999Date of Patent: December 26, 2000Assignee: Sharp Kabushiki KaishaInventors: Syouichi Fujita, Itaru Kawabata, Toshio Nishino, Hirofumi Sakita, Hideji Saiko, Mitsuru Tokuyama
-
Patent number: 6070035Abstract: 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.Type: GrantFiled: September 30, 1998Date of Patent: May 30, 2000Assignee: Sharp Kabushiki KaishaInventors: Syouichi Fujita, Eiji Sato, Hirofumi Sakita, Masato Asanuma, Itaru Kawabata, Kouichi Takenouchi
-
Patent number: 6035168Abstract: 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.Type: GrantFiled: December 30, 1998Date of Patent: March 7, 2000Assignee: Sharp Kabushiki KaishaInventors: Jitsuo Masuda, Hiroshi Kawamoto, Makoto Uehara, Yasutaka Maeda, Takeshi Wakabayashi, Takahiko Kimura, Tao Ou, Naotaka Funayama, Toshio Nishino, Yasuyuki Ishiguro, Syouichi Fujita, Hirofumi Sakita
-
Patent number: 5794097Abstract: The present invention relates to image forming device such as copying machines and laser printers, which use an electrophotographic (xerognaphic) process. A simple control method without using any additional complex means can equalize a surface potentional of a light-sensitive drum to keep a light-quality of an image formed even for the first rotation of the light-sensitive drum. A charge-removal prohibiting means, a charge-potentional changing means and a developing bias-potentional changing means are controlled in accordance with an extent of a change of a surface potential of a light-sensitive body, which depends upon a light fatigue and an ambient temperature of the light-sensitive body and/or a pause after a preceding image process.Type: GrantFiled: December 21, 1995Date of Patent: August 11, 1998Assignee: Sharp Kabushiki KaishaInventors: Kouji Shinkawa, Masaaki Ohtsuki, Mihoko Okada, Mitsuru Tokuyama, Hirofumi Sakita, Masatsugu Nakamura
-
Patent number: 5759735Abstract: A method for preparing an electrophotographic printing-use developer by mixing components of toner material, fusing and kneading the toner material, and then crushing and classifying the toner material, includes the step of arranging carbon black which is one of the components of the toner material to contain water before the mixing step. This arrangement permits even dispersion of water in the mixture of the components, prevents the flowability of the mixture from being lowered, and achieves stable kneading. Therefore, improved dispersion of the components is achieved. Since water adsorption is stable, water-treated carbon showing reduced water segregation is obtained. Consequently, high quality less foggy images with high resolution are obtained.Type: GrantFiled: January 29, 1997Date of Patent: June 2, 1998Assignee: Sharp Kabushiki KaishaInventors: Tadashi Nakamura, Kanshiro Okamoto, Hirofumi Sakita, Toshihiko Murakami, Yoshiaki Akazawa
-
Patent number: 5092345Abstract: Described herein is a cell sampler particularly suitable for sampling cells from the uterine endometrium as specimens in cytodiagnosis for uterine cancer, especially, for carcinoma corporis, the sampler including a handle slidably and rotatably inserted in a tube and a scraper portion in the form of a flexible loop with scraper blades for scraping sample cells. The scraper portion is protrudably retractable into the tube by sliding movements of the handle, and capable of sampling cells from entire regions of the endometrium in a safe and reliable manner.Type: GrantFiled: March 16, 1990Date of Patent: March 3, 1992Assignee: Anne Company LimitedInventor: Hirofumi Sakita