Patents by Inventor Takuji Yoneda

Takuji Yoneda 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: 7680429
    Abstract: A charging device, a process cartridge, and an image forming apparatus are provided. The charging device includes a charging roller configured to charge an image carrier and a cleaning roller configured to clean the charging roller while making contact with a surface of the charging roller. The charging device further includes a bearing member including a first portion configured to rotatably support a rotational shaft of the charging roller and a second portion configured to rotatably support a rotational shaft of the cleaning roller. The charging device also includes an elastic member provided outside of the second portion of the bearing member with respect to an axial direction of the rotational shaft of the cleaning roller such that the charging roller makes contact with the image carrier when the first portion of the bearing member is pressed by the elastic member.
    Type: Grant
    Filed: November 18, 2008
    Date of Patent: March 16, 2010
    Assignee: Ricoh Company, Ltd.
    Inventors: Muraishi Takaya, Hiromichi Ninomiya, Atsushi Sampe, Yoshiyuki Kimura, Hiroyuki Nagashima, Hiroshi Hosokawa, Ken Amemiya, Toshio Koike, Tokuya Ojimi, Takaaki Tawada, Takeshi Shintani, Yuji Arai, Takuji Yoneda, Masanori Kawasumi, Masami Tomita
  • Publication number: 20090087213
    Abstract: A charging device, a process cartridge, and an image forming apparatus are provided. The charging device includes a charging roller configured to charge an image carrier and a cleaning roller configured to clean the charging roller while making contact with a surface of the charging roller. The charging device further includes a bearing member including a first portion configured to rotatably support a rotational shaft of the charging roller and a second portion configured to rotatably support a rotational shaft of the cleaning roller. The charging device also includes an elastic member provided outside of the second portion of the bearing member with respect to an axial direction of the rotational shaft of the cleaning roller such that the charging roller makes contact with the image carrier when the first portion of the bearing member is pressed by the elastic member.
    Type: Application
    Filed: November 18, 2008
    Publication date: April 2, 2009
    Inventors: Muraishi Takaya, Hiromichi Ninomiya, Atsushi Sampe, Yoshiyuki Kimura, Hiroyuki Nagashima, Hiroshi Hosokawa, Ken Amemiya, Toshio Koike, Tokuya Ojimi, Takaaki Tawada, Takeshi Shintani, Yuji Arai, Takuji Yoneda, Masanori Kawasumi, Masami Tomita
  • Patent number: 7493075
    Abstract: A cleaning device, a process cartridge, and an image forming apparatus including an antifriction agent coating part and a toner removing part. The antifriction agent coating part coats a solid antifriction agent on the surface of an image support body, and is disposed in an upstream side from a cleaning blade with respect to a rotational direction of the image support body. The toner removing part removes toner particles, and is disposed in an upstream side from the antifriction agent coating part with respect to the rotational direction of the image support body and a portion of the toner removing part is positioned below a portion of the antifriction agent coating part in a vertical direction perpendicular to the ground.
    Type: Grant
    Filed: March 13, 2007
    Date of Patent: February 17, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Shintani, Takuji Yoneda, Toshio Koike, Masato Yanagida, Naohiro Kumagai, Hiroyuki Nagashima, Atsuhsi Sampe, Eisaku Murakami, Masanori Kawasumi, Takeshi Uchitani, Masami Tomita
  • Patent number: 7477862
    Abstract: There is provided a cleaning device for an image-forming device configured so as to be capable of preventing the image quality from deteriorating by being able to prevent the deterioration of the charging state caused by deposits of foreign matter without increasing costs. There is also provided a cleaning member that can make contact with the cleaning target-members. The cleaning member has a portion composed of melamine resin foam for making contact with at least the cleaning target members, and the melamine resin foam has an Asker F hardness of 5 to 25 points and a hardness variation of 5 points or less, and is used on the cleaning target members in a state obtained by heat compression from the original shape. The pressing member is furthermore disposed in contact with the cleaning member.
    Type: Grant
    Filed: February 8, 2005
    Date of Patent: January 13, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Muraishi Takaya, Hiromichi Ninomiya, Atsushi Sampe, Yoshiyuki Kimura, Hiroyuki Nagashima, Hiroshi Hosokawa, Ken Amemiya, Toshio Koike, Tokuya Ojimi, Takaaki Tawada, Takeshi Shintani, Yuji Arai, Takuji Yoneda, Masanori Kawasumi, Masami Tomita
  • Patent number: 7474867
    Abstract: A two-component developer including toner and magnetic carriers is provided. The two-component developer is characterized in that when a development device including a developer bearing member bearing the two-component developer is operated under a development condition of an image forming apparatus using a quasi-photoconductor in which a 10 ?m thick layer of tetrafluoroethylene resin is provided to a conductive material, the number of times of light emission occurring in a magnetic brush formed on the developer bearing member due to partial conduction in the magnetic brush is 10 times or less per second at an observation cross section that is perpendicular relative to a rotation axis of the developer bearing member.
    Type: Grant
    Filed: August 24, 2005
    Date of Patent: January 6, 2009
    Assignee: Ricoh Company, Ltd.
    Inventors: Takamasa Ozeki, Takayuki Maruta, Takuji Yoneda
  • Patent number: 7454186
    Abstract: The direct conversion receiving apparatus has a gain control amplifier for variably amplifying a base band signal based on a gain switching control signal. A high pass filter has a first circuit including capacitors connected in parallel that are inserted in a path connecting an input terminal to an output terminal and switching effective total capacitance of the capacitors based on a first time constant switching control signal, and a second circuit including a resistor for providing a predetermined direct current voltage to the output terminal and switching the effective resistance value of the resistor based on a second time constant switching control signal. A control circuit outputs the gain switching control signal, and the first and second time constant switching control signals according to the change of the gain control of said gain control amplifier.
    Type: Grant
    Filed: June 29, 2005
    Date of Patent: November 18, 2008
    Assignee: Panasonic Corporation
    Inventors: Takuji Yoneda, Hidehiko Kurimoto, Kaoru Ishida
  • Patent number: 7430377
    Abstract: An image forming apparatus includes an image carrier, a charging unit that charges the image carrier, a latent image forming unit that forms a latent image on the image carrier, a developing unit that develops the latent image to form a toner image, a transferring unit that transfers the toner image to a recording medium, a cleaning unit that cleans toner remaining on the image carrier, a lubricant applying unit that applies a solid lubricant to a surface of the image carrier, and a detecting unit that detects whether the image carrier is brand new. The toner has an average roundness of 0.94 or more. The lubricant applying unit is operated when the detecting unit detects that the image carrier is brand new.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: September 30, 2008
    Assignee: Ricoh Company, Limited
    Inventors: Toshio Koike, Ken Amemiya, Naohiro Kumagai, Masato Yanagida, Masanori Kawasumi, Takeshi Uchitani, Yutaka Takahashi, Yuji Arai, Takaaki Tawada, Masami Tomita, Takeshi Tabuchi, Eisaku Murakami, Takeshi Shintani, Takuji Yoneda
  • Publication number: 20070154246
    Abstract: A cleaning device, a process cartridge, an image forming apparatus and toner are disclosed to maintain improved cleaning performance for a long time. The cleaning device includes a cleaning blade, an antifriction agent coating part and a toner removing part. The cleaning blade is disposed in contact with a surface of an image support body. The antifriction agent coating part coats a solid antifriction agent on the surface of the image support body, and is disposed in an upstream side from the cleaning blade with respect to a rotational direction of the image support body. The toner removing part removes toner particles, and is disposed in an upstream side from the antifriction agent coating part with respect to the rotational direction of the image support body.
    Type: Application
    Filed: March 13, 2007
    Publication date: July 5, 2007
    Inventors: Takeshi Shintani, Takuji Yoneda, Toshio Koike, Masato Yanagida, Naohiro Kumagai, Hiroyuki Nagashima, Atsushi Sampe, Eisaku Murakami, Masanori Kawasumi, Takeshi Uchitani, Masami Tomita
  • Patent number: 7228099
    Abstract: A cleaning device, a process cartridge, an image forming apparatus and toner are disclosed to maintain improved cleaning performance for a long time. The cleaning device includes a cleaning blade, an antifriction agent coating part and a toner removing part. The cleaning blade is disposed in contact with a surface of an image support body. The antifriction agent coating part coats a solid antifriction agent on the surface of the image support body, and is disposed in an upstream side from the cleaning blade with respect to a rotational direction of the image support body. The toner removing part removes toner particles, and is disposed in an upstream side from the antifriction agent coating part with respect to the rotational direction of the image support body.
    Type: Grant
    Filed: May 3, 2004
    Date of Patent: June 5, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Takeshi Shintani, Takuji Yoneda, Toshio Koike, Masato Yanagida, Naohiro Kumagai, Hiroyuki Nagashima, Atsuhsi Sampe, Eisaku Murakami, Masanori Kawasumi, Takeshi Uchitani, Masami Tomita
  • Publication number: 20070036595
    Abstract: A cleaning unit includes a cleaning blade that cleans toner on an image carrier and a brush-shaped roller that applies a lubricant of a molded lubricant on the image carrier. The brush-shaped roller is insulative, and delivers the toner cleaned by the cleaning blade to inside of the cleaning unit.
    Type: Application
    Filed: October 25, 2006
    Publication date: February 15, 2007
    Inventors: Ken Amemiya, Masato Yanagida, Naohiro Kumagai, Takeshi Shintani, Takaaki Tawada, Yuji Arai, Toshio Koike, Takuji Yoneda, Takeshi Tabuchi, Yutaka Takahashi, Eisaku Murakami, Takeshi Uchitani, Masami Tomita, Masanori Kawasumi
  • Patent number: 7149465
    Abstract: A cleaning unit includes a cleaning blade that cleans toner on an image carrier and a brush-shaped roller that applies a lubricant of a molded lubricant on the image carrier. The brush-shaped roller is insulative, and delivers the toner cleaned by the cleaning blade to inside of the cleaning unit.
    Type: Grant
    Filed: August 20, 2004
    Date of Patent: December 12, 2006
    Assignee: Ricoh Company, Limited
    Inventors: Ken Amemiya, Masato Yanagida, Naohiro Kumagai, Takeshi Shintani, Takaaki Tawada, Yuji Arai, Toshio Koike, Takuji Yoneda, Takeshi Tabuchi, Yutaka Takahashi, Eisaku Murakami, Takeshi Uchitani, Masami Tomita, Masanori Kawasumi
  • Publication number: 20060115286
    Abstract: An image forming apparatus including an image bearing member configured to bear an electrostatic latent image; a charging device configured to charge the image bearing member by applying a DC voltage overlapped with an AC voltage to the image bearing member; an AC current detector configured to detect an AC current flowing through the image bearing member on a ground side of the image bearing member; a light irradiating device configured to irradiate the charged image bearing member with imagewise light to form the electrostatic latent image on the image bearing member; a developing device configured to develop the electrostatic latent image with a developer comprising a toner to form a toner image on the image bearing member; a transferring device configured to transfer the toner image onto a receiving material; and a cleaning device configured to clean a surface of the image bearing member.
    Type: Application
    Filed: November 28, 2005
    Publication date: June 1, 2006
    Inventors: Takeshi Uchitani, Ken Amemiya, Toshio Koike, Hiroshi Ono, Takatsugu Fujishiro, Tokuya Ojimi, Yuji Arai, Masanori Kawasumi, Takuji Yoneda, Haruji Mizuishi, Masaharu Yokono, Masami Tomita
  • Publication number: 20060009182
    Abstract: The direct conversion receiving apparatus has a gain control amplifier for variably amplifying a base band signal based on a gain switching control signal. A high pass filter has a first circuit including capacitors connected in parallel that are inserted in a path connecting an input terminal to an output terminal and switching effective total capacitance of the capacitors based on a first time constant switching control signal, and a second circuit including a resistor for providing a predetermined direct current voltage to the output terminal and switching the effective resistance value of the resistor based on a second time constant switching control signal. A control circuit outputs the gain switching control signal, and the first and second time constant switching control signals according to the change of the gain control of said gain control amplifier.
    Type: Application
    Filed: June 29, 2005
    Publication date: January 12, 2006
    Inventors: Takuji Yoneda, Hidehiko Kurimoto, Kaoru Ishida
  • Publication number: 20060001482
    Abstract: A filter device is provided that can easily achieve reduction in current consumption and whose variations can be corrected. A phase difference of a reference filter is detected by a phase difference detector, a control signal for correcting variations that is obtained as a result of the detection is held in a register, and a cut-off frequency of a main filter is selected according to the control signal thus held. Thus, once variations are detected, the reference filter and the phase difference detector that are used for detection of variations become no longer necessary and their operations can be halted, thereby achieving reduction in current consumption.
    Type: Application
    Filed: November 17, 2003
    Publication date: January 5, 2006
    Applicant: Matsushita Electric Industrial Co., Ltd.
    Inventors: Makoto Nakamura, Takuji Yoneda, Hidehiko Kurimoto, Takeaki Watanabe
  • Publication number: 20050281593
    Abstract: A two-component developer including toner and magnetic carriers is provided. The two-component developer is characterized in that when a development device including a developer bearing member bearing the two-component developer is operated under a development condition of an image forming apparatus using a quasi-photoconductor in which a 10 ?m thick layer of tetrafluoroethylene resin is provided to a conductive material, the number of times of light emission occurring in a magnetic brush formed on the developer bearing member due to partial conduction in the magnetic brush is 10 times or less per second at an observation cross section that is perpendicular relative to a rotation axis of the developer bearing member.
    Type: Application
    Filed: August 24, 2005
    Publication date: December 22, 2005
    Inventors: Takamasa Ozeki, Takayuki Maruta, Takuji Yoneda
  • Publication number: 20050191081
    Abstract: There is provided a cleaning device for an image-forming device configured so as to be capable of preventing the image quality from deteriorating by being able to prevent the deterioration of the charging state caused by deposits of foreign matter without increasing costs. There is also provided a cleaning member that can make contact with the cleaning target-members. The cleaning member has a portion composed of melamine resin foam for making contact with at least the cleaning target members, and the melamine resin foam has an Asker F hardness of 5 to 25 points and a hardness variation of 5 points or less, and is used on the cleaning target members in a state obtained by heat compression from the original shape. The pressing member is furthermore disposed in contact with the cleaning member.
    Type: Application
    Filed: February 8, 2005
    Publication date: September 1, 2005
    Inventors: Takaya Muraishi, Hiromichi Ninomiya, Atsushi Sampe, Yoshiyuki Kimura, Hiroyuki Nagashima, Hiroshi Hosokawa, Ken Amemiya, Toshio Koike, Tokuya Ojimi, Takaaki Tawada, Takeshi Shintani, Yuji Arai, Takuji Yoneda, Masanori Kawasumi, Masami Tomita
  • Publication number: 20050084271
    Abstract: An image forming apparatus includes an image carrier, a charging unit that charges the image carrier, a latent image forming unit that forms a latent image on the image carrier, a developing unit that develops the latent image to form a toner image, a transferring unit that transfers the toner image to a recording medium, a cleaning unit that cleans toner remaining on the image carrier, a lubricant applying unit that applies a solid lubricant to a surface of the image carrier, and a detecting unit that detects whether the image carrier is brand new. The toner has an average roundness of 0.94 or more. The lubricant applying unit is operated when the detecting unit detects that the image carrier is brand new.
    Type: Application
    Filed: August 20, 2004
    Publication date: April 21, 2005
    Inventors: Toshio Koike, Ken Amemiya, Naohiro Kumagai, Masato Yanagida, Masanori Kawasumi, Takeshi Uchitani, Yutaka Takahashi, Yuji Arai, Takaaki Tawada, Masami Tomita, Takeshi Tabuchi, Eisaku Murakami, Takeshi Shintani, Takuji Yoneda
  • Publication number: 20050074264
    Abstract: A cleaning unit includes a cleaning blade that cleans toner on an image carrier and a brush-shaped roller that applies a lubricant of a molded lubricant on the image carrier. The brush-shaped roller is insulative, and delivers the toner cleaned by the cleaning blade to inside of the cleaning unit.
    Type: Application
    Filed: August 20, 2004
    Publication date: April 7, 2005
    Inventors: Ken Amemiya, Masato Yanagida, Naohiro Kumagai, Takeshi Shintani, Takaaki Tawada, Yuji Arai, Toshio Koike, Takuji Yoneda, Takeshi Tabuchi, Yutaka Takahashi, Eisaku Murakami, Takeshi Uchitani, Masami Tomita, Masanori Kawasumi
  • Publication number: 20050002705
    Abstract: A cleaning device, a process cartridge, an image forming apparatus and toner are disclosed to maintain improved cleaning performance for a long time. The cleaning device includes a cleaning blade, an antifriction agent coating part and a toner removing part. The cleaning blade is disposed in contact with a surface of an image support body. The antifriction agent coating part coats a solid antifriction agent on the surface of the image support body, and is disposed in an upstream side from the cleaning blade with respect to a rotational direction of the image support body. The toner removing part removes toner particles, and is disposed in an upstream side from the antifriction agent coating part with respect to the rotational direction of the image support body.
    Type: Application
    Filed: May 3, 2004
    Publication date: January 6, 2005
    Inventors: Takeshi Shintani, Takuji Yoneda, Toshio Koike, Masato Yanagida, Naohiro Kumagai, Hiroyuki Nagashima, Atsushi Sampe, Eisaku Murakami, Masanori Kawasumi, Takeshi Uchitani, Masami Tomita
  • Publication number: 20040190946
    Abstract: A two-component developer including toner and magnetic carriers is provided. The two-component developer is characterized in that when a development device including a developer bearing member bearing the two-component developer is operated under a development condition of an image forming apparatus using a quasi-photoconductor in which a 10 &mgr;m thick layer of tetrafluoroethylene resin is provided to a conductive material, the number of times of light emission occurring in a magnetic brush formed on the developer bearing member due to partial conduction in the magnetic brush is 10 times or less per second at an observation cross section that is perpendicular relative to a rotation axis of the developer bearing member.
    Type: Application
    Filed: December 29, 2003
    Publication date: September 30, 2004
    Inventors: Shigekazu Enoki, Osamu Ariizumi, Hisao Kurosu, Shinichi Namekata, Takamasa Ozeki, Takayuki Maruta, Takuji Yoneda