Patents by Inventor Kouji Shinkawa
Kouji Shinkawa 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).
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Publication number: 20200291600Abstract: A boom includes a body and a base end bracket. The body includes a straight section and a wide section. When viewed from above, a width of the straight section is substantially constant. When viewed from above, a width of the wide section increases toward the base end bracket. The straight section and the wide section are smoothly continuous to each other.Type: ApplicationFiled: September 28, 2017Publication date: September 17, 2020Inventors: Nobuyasu SUGIHARA, Yuki NAKATANI, Shinpei UTOU, Kouji SHINKAWA, Satoru KUBOTA, Shuhei WATANABE, Tooru TSUJI, Kazuo TAKAHASHI, Kenji SANADA
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Patent number: 7934316Abstract: An object of the present invention is to provide a charging roller (i) which includes a rubber member whose surface is subjected to a hardening treatment using a solvent containing at least an isocyanate compound and (ii) which can prevent leakage of an ionic conductive agent even if the charging roller is placed under conditions of high temperature and high humidity for a long time. The charging roller is made by forming a rubber layer on a metal core. The rubber layer is an epichlorohydrin based rubber base material to which an ionic conductive agent is added, the rubber layer being subjected to a surface treatment by applying a solution containing the isocyanate compound and heating it. This surface treatment is carried out under such conditions that a coefficient of dynamic friction at a contact portion between the rubber layer and a photoreceptor becomes 0.4 or less.Type: GrantFiled: September 4, 2009Date of Patent: May 3, 2011Assignee: Sharp Kabushiki KaishaInventors: Toshiaki Kagawa, Kouji Shinkawa, Tohru Sakuwa
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Patent number: 7869743Abstract: An image forming apparatus in which a charging roller charges an image carrier to which a lubricant is applied prevents slip of the charging roller. The charging roller is composed of a metal core and a rubber layer mainly made of an epichlorohydrin rubber formed around the metal core. A surface of this rubber layer is hardened with a surface treating solution containing an isocyanate compound. The surface of this rubber layer is also subjected to three abrading processes including two stone grinding processes and one lapping process so that a ten-point height of irregularities Rz thereof becomes 11 ?m or more.Type: GrantFiled: April 24, 2007Date of Patent: January 11, 2011Assignee: Sharp Kabushiki KaishaInventors: Toshiaki Kagawa, Kouji Shinkawa, Tohru Sakuwa
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Patent number: 7668484Abstract: The invention delivers a charging roller which is capable of preventing current leakage to a photoreceptor throughout life-time and which has a stable resistance value throughout life-time. The charging roller contains a metal core and a rubber layer formed on the core. The rubber layer is an epichlorohydrin-based rubber base material to which an electronic conductive agent and an ionic conductive agent are added. The rubber layer is subjected to surface processing by spraying the surface with a solution containing an isocyanate compound and heating. The amount of the electronic conductive agent added to the rubber base material is limited so that a volume resistivity when only the electronic conductive agent is added to the rubber base material is 1.46×106 ?·cm or greater. In addition, the amount of the added ionic conductive agent is increased so that a volume resistivity when the electronic conductive agent and the ionic conductive agent are added to the rubber base material is 1.93×106 ?·cm or less.Type: GrantFiled: April 6, 2007Date of Patent: February 23, 2010Assignee: Sharp Kabushiki KaishaInventors: Toshiaki Kagawa, Kouji Shinkawa, Tohru Sakuwa
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Publication number: 20100003413Abstract: An object of the present invention is to provide a charging roller (i) which includes a rubber member whose surface is subjected to a hardening treatment using a solvent containing at least an isocyanate compound and (ii) which can prevent leakage of an ionic conductive agent even if the charging roller is placed under conditions of high temperature and high humidity for a long time. The charging roller is made by forming a rubber layer on a metal core. The rubber layer is an epichlorohydrin based rubber base material to which an ionic conductive agent is added, the rubber layer being subjected to a surface treatment by applying a solution containing the isocyanate compound and heating it. This surface treatment is carried out under such conditions that a coefficient of dynamic friction at a contact portion between the rubber layer and a photoreceptor becomes 0.4 or less.Type: ApplicationFiled: September 4, 2009Publication date: January 7, 2010Applicant: SHARP KABUSHIKI KAISHAInventors: Toshiaki Kagawa, Kouji Shinkawa, Tohru Sakuwa
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Publication number: 20070271792Abstract: An object of the present invention is to provide a charging roller (i) which includes a rubber member whose surface is subjected to a hardening treatment using a solvent containing at least an isocyanate compound and (ii) which can prevent leakage of an ionic conductive agent even if the charging roller is placed under conditions of high temperature and high humidity for a long time. The charging roller is made by forming a rubber layer on a metal core. The rubber layer is an epichlorohydrin based rubber base material to which an ionic conductive agent is added, the rubber layer being subjected to a surface treatment by applying a solution containing the isocyanate compound and heating it. This surface treatment is carried out under such conditions that a coefficient of dynamic friction at a contact portion between the rubber layer and a photoreceptor becomes 0.4 or less.Type: ApplicationFiled: April 19, 2007Publication date: November 29, 2007Applicant: SHARP KABUSHIKI KAISHAInventors: Toshiaki Kagawa, Kouji Shinkawa, Tohru Sakuwa
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Publication number: 20070253740Abstract: An image forming apparatus in which a charging roller charges an image carrier to which a lubricant is applied prevents slip of the charging roller. The charging roller is composed of a metal core and a rubber layer mainly made of an epichlorohydrin rubber formed around the metal core. A surface of this rubber layer is hardened with a surface treating solution containing an isocyanate compound. The surface of this rubber layer is also subjected to three abrading processes including two,stone grinding processes and one lapping process so that a ten-point height of irregularities Rz thereof becomes 11 ?m or more.Type: ApplicationFiled: April 24, 2007Publication date: November 1, 2007Applicant: SHARP KABUSHIKI KAISHAInventors: Toshiaki Kagawa, Kouji Shinkawa, Tohru Sakuwa
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Publication number: 20070253738Abstract: In an image forming apparatus in which a charging roller charges a photoreceptor which is rotating at high speed, damages of the photoreceptor and the charging roller are prevented. The photoreceptor included in an electrophotographic image forming apparatus is rotated at high speed so that a speed of a peripheral surface of the photoreceptor is 225 mm per second or more. Then, the charging roller is rotated by contacting the photoreceptor, so as to charge the photoreceptor. Here, a surface pressure M of a contact portion between the photoreceptor and the charging roller is set to more than 0.8 g/mm2 but not more than 3.5 g/mm2.Type: ApplicationFiled: April 10, 2007Publication date: November 1, 2007Applicant: SHARP KABUSHIKI KAISHAInventors: Tohru Sakuwa, Kouji Shinkawa, Toshiaki Kagawa
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Publication number: 20070253737Abstract: The invention delivers a charging roller which is capable of preventing current leakage to a photoreceptor throughout life-time and which has a stable resistance value throughout life-time. The charging roller contains a metal core and a rubber layer formed on the core. The rubber layer is an epichlorohydrin-based rubber base material to which an electronic conductive agent and an ionic conductive agent are added. The rubber layer is subjected to surface processing by spraying the surface with a solution containing an isocyanate compound and heating. The amount of the electronic conductive agent added to the rubber base material is limited so that a volume resistivity when only the electronic conductive agent is added to the rubber base material is 1.46×106 ?·cm or greater. In addition, the amount of the added ionic conductive agent is increased so that a volume resistivity when the electronic conductive agent and the ionic conductive agent are added to the rubber base material is 1.93×106 ?·cm or less.Type: ApplicationFiled: April 6, 2007Publication date: November 1, 2007Applicant: Sharp Kabushiki KaishaInventors: Toshiaki Kagawa, Kouji Shinkawa, Tohru Sakuwa
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Patent number: 6405009Abstract: In image forming apparatuses producing recycled toner from residual toner and recycling the recycled toner, the toner composition changes, and the toner properties worsen, because the external additive contained in the collected residual toner that is collected with a cleaning portion decreases during the image formation. The residual toner that has been collected with the cleaning portion is conveyed through a conveyance path to a collected residual toner storage, and external additive is supplemented from an external additive cartridge, and mixed with being stirred to produce recycled toner. In a fresh toner storage, fresh toner and recycled toner are stirred, and when the amount of toner in a developing portion drops below a predetermined amount, toner is conveyed from the fresh toner storage through a conveyance path to the developing portion. The toner that has been conveyed to the developing portion is supplied to a photosensitive drum.Type: GrantFiled: October 5, 2000Date of Patent: June 11, 2002Assignee: Sharp Kabushiki KaishaInventors: Kouji Shinkawa, Takashi Sakai, Takayuki Yamanaka, Atsushi Inoue, Jitsuo Masuda
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Patent number: 6157807Abstract: 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.Type: GrantFiled: October 27, 1999Date of Patent: December 5, 2000Assignee: Sharp Kabushiki KaishaInventors: Kouichi Takenouchi, Masato Asanuma, Kouji Shinkawa, Hiroo Naoi, Syouichi Fujita
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Patent number: 5842089Abstract: The present invention is intended to provide a compact development apparatus using a nonmagnetic one-component toner. The apparatus comprises a toner storage container, a toner supply roller, a toner passage through which supplied toner passes, and an attracting fan for attracting the toner and generating a toner powder stream. The toner is held in the toner storage container. The toner supply roller supplies the toner from a supply port of the storage container. The toner passage is provided with an opening opposite to a photosensitive drum. The toner supplied into the toner passage and frictionally charged is attracted by the attracting fan. The toner travels from the opening to the drum. The toner adheres to an electrostatic latent image on the drum and thus the image is developed. Unused toner is transported into the toner passage and recovered.Type: GrantFiled: July 24, 1997Date of Patent: November 24, 1998Assignee: Sharp Kabushiki KaishaInventors: Hisashi Kunihiro, Kouji Shinkawa, Masato Asanuma, Yukihisa Imaue, Itaru Kawabata
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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