Patents by Inventor Haruji Mizuishi

Haruji Mizuishi 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: 8428488
    Abstract: A cleaning roller cleaning a surface of a cleaning component, wherein the cleaning roller is provided in a roller configuration having a cylindrical shape and has a portion in contact with the cleaning component, the portion being made of a melamine resin foam having a continuous foam structure, the melamine resin foam being provided by heating compression from an original configuration in a radial direction, and wherein the portion in contact with the cleaning component has a continuous foam structure and a tensile strength in a range of 1.7±0.5 kg/cm2, and an image forming apparatus incorporating the same.
    Type: Grant
    Filed: June 30, 2011
    Date of Patent: April 23, 2013
    Assignee: Ricoh Company, Ltd.
    Inventors: Haruji Mizuishi, Tokuya Ojimi, Toshio Koike, Takeshi Shintani, Yuji Arai, Takuzi Yoneda, Ken Amemiya, Takaaki Tawada, Masami Tomita, Masanori Kawasumi, Takaya Muraishi, Hiroomi Harada, Hiromichi Ninomiya
  • Publication number: 20110262179
    Abstract: A cleaning roller cleaning a surface of a cleaning component, wherein the cleaning roller is provided in a roller configuration having a cylindrical shape and has a portion in contact with the cleaning component, the portion being made of a melamine resin foam having a continuous foam structure, the melamine resin foam being provided by heating compression from an original configuration in a radial direction, and wherein the portion in contact with the cleaning component has a continuous foam structure and a tensile strength in a range of 1.7±0.5 kg/cm2, and an image forming apparatus incorporating the same.
    Type: Application
    Filed: June 30, 2011
    Publication date: October 27, 2011
    Inventors: Haruji MIZUISHI, Tokuya Ojimi, Toshio Koike, Takeshi Shintani, Yuji Arai, Takuzi Yoneda, Ken Amemiya, Takaaki Tawada, Masami Tomita, Masanori Kawasumi, Takaya Muraishi, Hiroomi Harada, Hiromichi Ninomiya
  • Patent number: 8000627
    Abstract: The present invention provides a charging device which comprises a charging roller (14a) and a cleaning component (14b). The charging roller charges a surface of an image-recording medium (11) with a voltage which is applied from an external source. The cleaning component cleans a surface of the charging roller. The charging roller includes a resistance adjustment layer which is made of a resin composite and formed on an outer periphery of a core metal. The hardness of the charging roller is 45 degrees or more in JIS D hardness. The cleaning component has a portion which is in contact with the charging roller. This portion is made of resin foam which has a continuous foam structure. The density of the resin foam is 5 to 15 kg/m3 and its tensile strength is 1.7±0.5 kg/cm2.
    Type: Grant
    Filed: March 4, 2005
    Date of Patent: August 16, 2011
    Assignee: Ricoh Company, Ltd.
    Inventors: Haruji Mizuishi, Tokuya Ojimi, Toshio Koike, Takeshi Shintani, Yuji Arai, Takuzi Yoneda, Ken Amemiya, Takaaki Tawada, Masami Tomita, Masanori Kawasumi, Takaya Muraishi, Hiroomi Harada, Hiromichi Ninomiya
  • Patent number: 7826786
    Abstract: In an image forming apparatus, an area applied with a lubricant, i.e., an area of a lubricant layer having a uniform thickness, is obtained by spreading the lubricant by a lubricant smoothing blade. The area applied with a lubricant covers an area cleaned by a cleaning blade, i.e., a contact portion of the cleaning blade with a photoconductor.
    Type: Grant
    Filed: December 6, 2005
    Date of Patent: November 2, 2010
    Assignee: Ricoh Company, Limited
    Inventors: Takeo Suda, Shinichi Kawahara, Takatsugu Fujishiro, Tokuya Ojimi, Takeshi Tabuchi, Masato Yanagida, Haruji Mizuishi, Teruyuki Kasuga, Hiroomi Harada, Shuji Tanaka, Takaaki Tawada, Hiroshi Ono, Ken Amemiya, Toshio Koike, Yuji Arai, Masanori Kawasumi, Takuzi Yoneda, Masami Tomita, Yutaka Takahashi, Yoshio Hattori, Keiichi Yoshida
  • Patent number: 7672635
    Abstract: A lubricant supplying device including a molded lubricant having a Martens hardness of about 40 N/mm2 to about 70 N/mm2 measured with a test force of 50 mN and a load-applying period of 30 seconds, a rotative member including a fibrous brush of a thickness of about 5 deniers to about 15 deniers in a circumference of a rotative supporting axis of the rotative member with a density of about 20,000 fibers to about 100,000 fibers per square inch, and configured to apply lubricant shavings of the molded lubricant to an image bearing member held in contact with a cleaning member and to remove the lubricant shavings remaining on the surface of the image bearing member, and a pressing member configured to press the molded lubricant against the rotative member at a pressure force ranging from about 2 N/m to about 12 N/m.
    Type: Grant
    Filed: March 20, 2008
    Date of Patent: March 2, 2010
    Assignee: Ricoh Co., Ltd.
    Inventors: Yoshiki Hozumi, Toshio Koike, Ken Amemiya, Masanori Kawasumi, Yuji Arai, Tokuya Ojimi, Takuzi Yoneda, Masami Tomita, Hiroshi Ono, Takatsugu Fujishiro, Haruji Mizuishi
  • Patent number: 7539451
    Abstract: An image forming apparatus having an image support body configured to support a latent image, a charging member configured to provide a substantially uniform charge to a surface of the image support body and a spacer coupled to the charging member and configured to contact the image support body to maintain a gap between the image support body and the charging member. A cleaning part is configured to clean the surface of the image support body after developer is applied to the image support body and transferred to a recording medium. The cleaning part is configured to satisfy the relationship A+B?C, where A is a width of the effective charging area of the charging member that charges a surface of the image support body, B is a total width of the spacer that contacts the image support body, and C is a width of cleaning part that contacts the image support body.
    Type: Grant
    Filed: September 13, 2005
    Date of Patent: May 26, 2009
    Assignee: Ricoh Company Ltd.
    Inventors: Masanori Kawasumi, Haruji Mizuishi, Tokuya Ojimi, Toshio Koike, Takeshi Shintani, Yuji Arai, Tazuki Yoneda, Ken Amemiya, Takaaki Tawada, Masami Tomita, Takeshi Uchitani, Nobuo Kuwahara, Hiroyuki Nagashima, Masato Yanagida
  • Patent number: 7522850
    Abstract: A carrier and a dummy toner are stored in a developing unit of a process cartridge in a brand new status. A plurality of process cartridges corresponding to a plurality of color toners is used in common. The color toners are respectively supplied to the developing unit from toner supply units after the process cartridges in the brand new status are installed in installation sections in a main unit of an image forming apparatus.
    Type: Grant
    Filed: November 17, 2006
    Date of Patent: April 21, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuhito Watanabe, Satoshi Narumi, Shinji Tamaki, Satoshi Hatori, Tsutomu Katoh, Haruji Mizuishi, Tetsuroh Tanigawa, Misao Tanzawa
  • Patent number: 7493061
    Abstract: A process cartridge is provided with a frame body made up of at least first and second frame bodies that are movable relative to each other to form a space, a frame body positioning member positioning the first and second frame bodies, a latent image bearing member supported by the frame body and replaceable via the space formed by the first and second frame bodies, a developing unit supplying a developing agent to the latent image bearing member, and a developing position determining member. The developing position determining member is disposed at a non-overlapping position relative to the frame body positioning member, and positions the developing unit with respect to the frame body.
    Type: Grant
    Filed: August 24, 2004
    Date of Patent: February 17, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Satoshi Hatori, Kazuhito Watanabe, Satoshi Narumi, Shinji Tamaki, Tsutomu Katoh, Haruji Mizuishi, Tetsuroh Tanigawa
  • Patent number: 7477856
    Abstract: An image forming apparatus including an image bearing member, a charging member, and a measuring member. The image forming member is configured to bear an image. The charging member is configured to charge a surface of the image bearing member when a direct current bias voltage is added to at least an alternating bias voltage which is applied to the charging member, and has a frequency fc of the alternating bias voltage. The measuring member is configured to measure a potential of the surface of the image bearing member, and has a drive frequency fvsen. The relationship of the frequency fc and the drive frequency fvsen is expressed as fc?fvsen×n and fc×n?fvsen.
    Type: Grant
    Filed: November 14, 2005
    Date of Patent: January 13, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Takuzi Yoneda, Hiroshi Ono, Masanori Kawasumi, Yuji Arai, Toshio Koike, Ken Amemiya, Tokuya Ohjimi, Takatsugu Fujishiro, Masami Tomita, Haruji Mizuishi, Hitoshi Ishibashi
  • Publication number: 20080175635
    Abstract: A lubricant supplying device including a molded lubricant having a Martens hardness of about 40 N/mm2 to about 70 N/mm2 measured with a test force of 50 mN and a load-applying period of 30 seconds, a rotative member including a fibrous brush of a thickness of about 5 deniers to about 15 deniers in a circumference of a rotative supporting axis of the rotative member with a density of about 20,000 fibers to about 100,000 fibers per square inch, and configured to apply lubricant shavings of the molded lubricant to an image bearing member held in contact with a cleaning member and to remove the lubricant shavings remaining on the surface of the image bearing member, and a pressing member configured to press the molded lubricant against the rotative member at a pressure force ranging from about 2 N/m to about 12 N/m.
    Type: Application
    Filed: March 20, 2008
    Publication date: July 24, 2008
    Inventors: Yoshiki Hozumi, Toshio Koike, Ken Amemiya, Masanori Kawasumi, Yuji Arai, Tokuya Ojimi, Takuzi Yoneda, Masami Tomita, Hiroshi Ono, Takatsugu Fujishiro, Haruji Mizuishi
  • Patent number: 7373101
    Abstract: A lubricant supplying device including a molded lubricant having a Martens hardness of approximately 40 N/mm2 to approximately 70 N/mm2 measured with a test force of 50 mN and a load-applying period of 30 seconds, a rotative member including a fibrous brush of a thickness of approximately 5 deniers to approximately 15 deniers in a circumference of a rotative supporting axis of the rotative member with a density of approximately 20,000 fibers to approximately 100,000 fibers per square inch, and configured to apply lubricant shavings of the molded lubricant to an image bearing member held in contact with a cleaning member and remove the lubricant shavings remaining on the surface of the image bearing member, and a pressing member configured to press contact the molded lubricant with the rotative member at a pressure force ranging from approximately 2 N/m to approximately 12 N/m.
    Type: Grant
    Filed: December 23, 2005
    Date of Patent: May 13, 2008
    Assignee: Ricoh Co., Ltd.
    Inventors: Yoshiki Hozumi, Toshio Koike, Ken Amemiya, Masanori Kawasumi, Yuji Arai, Tokuya Ojimi, Takuzi Yoneda, Masami Tomita, Hiroshi Ono, Takatsugu Fujishiro, Haruji Mizuishi
  • Patent number: 7333744
    Abstract: A charge apparatus charges by uniformly superimposing an alternate current bias voltage with a fixed frequency over a direct current bias voltage as the charge bias voltage on a photosensitive member. An exposure apparatus exposes the surface of the charged photosensitive member based on image data, and writes a latent image, and a developing apparatus supplies toner to and makes visible the latent image formed on the surface of the photosensitive member. A transfer apparatus transfers the visible image on the photosensitive member to a transfer medium, and a cleaning apparatus cleans the surface of the photosensitive member after transfer.
    Type: Grant
    Filed: November 30, 2005
    Date of Patent: February 19, 2008
    Assignee: Ricoh Company, Ltd.
    Inventors: Eiji Shimojo, Haruji Mizuishi, Tokuya Ojimi, Masanori Kawasumi, Takuzi Yoneda, Ken Amemiya, Takatsugu Fujishiro, Hiroshi Ono, Toshio Koike, Masami Tomita, Yuji Arai, Takeshi Uchitani
  • Publication number: 20080013998
    Abstract: A powder transport unit for transporting powders includes a transport pipe, a powder transport member, and a regulating member. The transport pipe is curvingly extended. The powder transport member is disposed in an entire length of the transport pipe and rotates in the transport pipe to transport the powders. The regulating member is integrally formed with the transport pipe at a downstream end of the transport pipe, and regulates a length of the powder transport member disposed in the entire length of the transport pipe. The regulating member includes an exit hole to pass through the powders transported by the powder transport member in the transport pipe.
    Type: Application
    Filed: September 28, 2006
    Publication date: January 17, 2008
    Inventors: Naohiro Kumagai, Masato Yanagida, Shuji Tanaka, Takatsugu Fujishiro, Hiroomi Harada, Takeshi Tabuchi, Tokuya Ojimi, Chohtaroh Kataoka, Takaaki Tawada, Shinichi Kawahara, Haruji Mizuishi
  • Patent number: 7313347
    Abstract: A cleaning device, a process cartridge, an image forming apparatus, and toner to maintain improved cleaning performance for a long time. The cleaning device includes a cleaning blade, a lubricant applying part, and a toner removing part. The cleaning blade is disposed in contact with a surface of an image bearing member. The lubricant applying part coats a solid lubricant on the surface of the image bearing member, and is disposed in an upstream side from the cleaning blade with respect to a rotational direction of the image bearing member. The toner removing part removes toner particles, and is disposed in an upstream side from the lubricant applying part with respect to the rotational direction of the image bearing member.
    Type: Grant
    Filed: August 22, 2005
    Date of Patent: December 25, 2007
    Assignee: Ricoh Company Ltd.
    Inventors: Takeshi Shintani, Takuzi Yoneda, Ken Amemiya, Takaaki Tawada, Tokuya Ojimi, Toshio Koike, Yuji Arai, Masanori Kawasumi, Masami Tomita, Hideyo Watanabe, Satoshi Takano, Haruji Mizuishi, Hiroshi Ono, Hiroshi Mizusawa, Satoshi Hatori, Takeshi Tabuchi, Akira Fujimori, Kaoru Yoshino
  • Publication number: 20070196123
    Abstract: The present invention provides a charging device which comprises a charging roller (14a) and a cleaning component (14b). The charging roller charges a surface of an image-recording medium (11) with a voltage which is applied from an external source. The cleaning component cleans a surface of the charging roller. The charging roller includes a resistance adjustment layer which is made of a resin composite and formed on an outer periphery of a core metal. The hardness of the charging roller is 45 degrees or more in JIS D hardness. The cleaning component has a portion which is in contact with the charging roller This portion is made of resin foam which has a continuous foam structure. The density of the resin foam is 5 to 15 kg/m3 and its tensile strength is 1.7±0.5 kg/cm2.
    Type: Application
    Filed: March 4, 2005
    Publication date: August 23, 2007
    Inventors: Haruji Mizuishi, Tokuya Ojimi, Toshio Koike, Takeshi Shintani, Yuji Arai, Takuzi Yoneda, Ken Amemiya, Takaaki Tawada, Masami Tomita, Masanori Kawasumi, Takaya Muraishi, Hiroomi Harada, Hiromichi Ninomiya
  • Publication number: 20070183824
    Abstract: In an image forming apparatus, an area applied with a lubricant, i.e., an area of a lubricant layer having a uniform thickness, is obtained by spreading the lubricant by a lubricant smoothing blade. The area applied with a lubricant covers an area cleaned by a cleaning blade, i.e., a contact portion of the cleaning blade with a photoconductor.
    Type: Application
    Filed: December 6, 2005
    Publication date: August 9, 2007
    Inventors: Takeo Suda, Shinichi Kawahara, Takatsugu Fujishiro, Tokuya Ojimi, Takeshi Tabuchi, Masato Yanagida, Haruji Mizuishi, Teruyuki Kasuga, Hiroomi Harada, Shuji Tanaka, Takaaki Tawada, Hiroshi Ono, Ken Amemiya, Toshio Koike, Yuji Arai, Masanori Kawasumi, Takuzi Yoneda, Masami Tomita, Yutaka Takahashi, Yoshio Hattori, Keiichi Yoshida
  • Patent number: 7209698
    Abstract: An image forming apparatus includes an image bearing member configured to bear a toner image on a surface thereof. A charging mechanism is configured to uniformly charge the surface of the image bearing member. An intermediate transfer mechanism is configured to transfer the toner image from the image bearing member onto an image receiver. A cleaning mechanism is configured to clean the surface of the image bearing member after the toner image is transferred onto the image receiver. A lubricant supplying mechanism is configured to supply a lubricant contained therein onto the surface of the image bearing member and form a thin layer using a lubricating blade. The lubricant supplying mechanism is disposed between the cleaning mechanism and the charging mechanism.
    Type: Grant
    Filed: August 23, 2004
    Date of Patent: April 24, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Takaaki Tawada, Shinichi Kawahara, Takeo Suda, Chohtaroh Kataoka, Keiichi Yoshida, Haruji Mizuishi
  • Publication number: 20070071499
    Abstract: A carrier and a dummy toner are stored in a developing unit of a process cartridge in a brand new status. A plurality of process cartridges corresponding to a plurality of color toners is used in common. The color toners are respectively supplied to the developing unit from toner supply units after the process cartridges in the brand new status are installed in installation sections in a main unit of an image forming apparatus.
    Type: Application
    Filed: November 17, 2006
    Publication date: March 29, 2007
    Inventors: Kazuhito WATANABE, Satoshi Narumi, Shinji Tamaki, Satoshi Hatori, Tsutomu Katoh, Haruji Mizuishi, Tetsuroh Tanigawa, Misao Tanzawa
  • Patent number: 7177555
    Abstract: The image forming apparatus comprises a photoconductor, a latent electrostatic image forming unit for forming a latent electrostatic image on the photoconductor, a developing unit for developing the latent electrostatic image using a developer comprising a toner to form a visible image, a transfer unit for transferring the visible image to a recording medium, a cleaning unit for removing the developer remained on the photoconductor surface and a developer amount detection unit for detecting developer amount adhering to the photoconductor surface by a reflecting photosensor, wherein the developer stirring time per copy when one copy is made from an original, is 2 to 6 times the developer stirring time per copy when two or more copies are made from the original, wherein the toner comprises at least a binder resin and a wax, and the dynamic frictional coefficient of the toner is 0.15 to 0.45.
    Type: Grant
    Filed: January 15, 2004
    Date of Patent: February 13, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Bing Shu, Mitsuo Aoki, Haruji Mizuishi, Mikio Ishibashi, Masaru Tanaka, Shinji Tamaki, Hiroshi Mizusawa, Shin Hasegawa
  • Patent number: 7158730
    Abstract: A carrier and a dummy toner are stored in a developing unit of a process cartridge in a brand new status. A plurality of process cartridges corresponding to a plurality of color toners is used in common. The color toners are respectively supplied to the developing unit from toner supply units after the process cartridges in the brand new status are installed in installation sections in a main unit of an image forming apparatus.
    Type: Grant
    Filed: August 6, 2004
    Date of Patent: January 2, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Kazuhito Watanabe, Satoshi Narumi, Shinji Tamaki, Satoshi Hatori, Tsutomu Katoh, Haruji Mizuishi, Tetsuroh Tanigawa, Misao Tanzawa