Patents by Inventor Akira Nagahara

Akira Nagahara 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: 6540792
    Abstract: A fiber structure comprising cellulose fibers crosslinked by using a crosslinking agent and synthetic fibers, characterized in that the crosslinking index represented by the following formula of the cellulose fibers is in a range of 1 to 4, and that the synthetic fibers contain an antimicrobial agent having an inorganic value/organic value ratio of 0.3 to 1.4. This structure has antimicrobial property excellent in industrial washing durability and also has shape stability such as crease resistance and shrinkage resistance. Crosslinking index=A−B where A is the coefficient of moisture absorption of the fiber structure after crosslinking in an atmosphere of 30° C. and 90% RH (%), and B is the coefficient of moisture absorption of the fiber structure after crosslinking in an atmosphere of 20° C. and 65% RH (%).
    Type: Grant
    Filed: April 3, 2000
    Date of Patent: April 1, 2003
    Assignee: Toray Industries, Inc.
    Inventors: Masaki Ishii, Atsushi Horiuchi, Katsuya Okajima, Akira Nagahara, Naoaki Ito, Hidenobu Honda, Kouichi Saito, Yukikazu Nanri
  • Publication number: 20010022906
    Abstract: Disclosed is an image forming apparatus which will form images in both a horizontal position and an upright position. This image forming apparatus comprises a rotary endless latent image carrier; an image forming unit for forming an electrostatic latent image on the latent image carrier; a developing unit for developing the electrostatic latent image on the latent image carrier with a powdery developer; a toner supplementing mechanism, attached to the developing unit with inclination to a gravitational direction of the apparatus, for supplementing toners to the developing unit; and a transfer unit for transferring the developed image on the latent image carrier to a sheet. With this design, the apparatus can stably supply toners to the developing unit, regardless of the position in which the apparatus is set.
    Type: Application
    Filed: March 30, 1994
    Publication date: September 20, 2001
    Inventors: HIROYUKI KAWAI, SHINJI SATO, AKIRA NAGAHARA, SACHIO SASAKI, MITSURU SATO, TAKEFUMI TAKAHASHI, MASAHIRO WANOU, MASAO KONISHI
  • Patent number: 6128463
    Abstract: An image forming device includes an image forming part which forms an image on a recording medium; a recording medium switchback portion which receives the recording medium on a first run, one side of which has been printed when passing the image forming part, and sends the recording medium for a second run; a recording medium path which communicates with the recording medium switchback portion so as to send the recording medium to and from the recording medium switchback portion; an inverted recording medium transfer path through which the recording medium is sent to the image forming part again with an upper surface and a lower surface of the recording medium reversed; and a recording medium transfer part which transfers the recording medium along the inverted recording medium transfer path.
    Type: Grant
    Filed: May 30, 1997
    Date of Patent: October 3, 2000
    Assignee: Fujitsu Limited
    Inventors: Yoshiya Matsumoto, Shigeo Nonoyama, Tetsuya Takei, Nobuo Kuwabara, Hiroshi Kera, Takefumi Takahashi, Yoshio Yamaguchi, Akira Nagahara
  • Patent number: 5852757
    Abstract: An electrophotographic image forming apparatus including a toner circulating mechanism for recovering a residual toner scraped from a photosensitive drum to a developing device. The developing device includes a housing for defining a toner chamber, a developing roller rotatably mounted in the housing, an agitator rotatably mounted in the housing and provided in the toner chamber, and a partition member mounted to the housing to define a carrier chamber between the partition member and the developing roller. The toner circulating mechanism directly returns the residual toner scraped from the photosensitive drum to the toner chamber in the developing device. The toner chamber may contain a foreign matter removing device. The partition member may have various shapes.
    Type: Grant
    Filed: July 16, 1996
    Date of Patent: December 22, 1998
    Assignee: Fujitsu Limited
    Inventors: Toshio Tooda, Yoshio Yamaguchi, Nobuo Kuwabara, Mituru Sato, Haruyasu Watanabe, Akira Nagahara, Sachio Sasaki, Yoshiya Ishiyama, Hiroshi Kera, Masanori Nishido, Hisashi Hanzawa
  • Patent number: 5848343
    Abstract: An electrophotographic image forming apparatus includes an electrostatic latent image carrying body, an electrifying unit for electrifying the image carrying body, a light irradiating unit to form an electrostatic latent image in accordance to image information, a developing unit for discharging toner to the image carrying body to develop the latent image, a transfer unit for transferring the toner image to a recording sheet, and a cleaner for removing residual toner on the image carrying body. The toner removed from the image carrying body is recirculated to the developer receiving box. An additional toner image is formed on a position other than a first position where the electrostatic latent image is formed in accordance with the image information. The toner is removed by the cleaner without being transferred to the recording sheet and recirculated from the image carrying body to the developer receiving box.
    Type: Grant
    Filed: July 1, 1997
    Date of Patent: December 8, 1998
    Assignee: Fujitsu Limited
    Inventors: Takefumi Takahashi, Shizuo Takano, Yoshio Yamaguchi, Hiroshi Kera, Akira Nagahara, Yoshiya Ishiyama, Hideki Kamaji, Toshio Tooda
  • Patent number: 5845184
    Abstract: A developing apparatus is provided for developing an electrostatic latent image on a latent image carrier by supplying the latent image carrier with a developer. This developing apparatus includes a toner accommodating chamber for accommodating magnetic toners. The apparatus also includes a developing roller, having a plurality of fixed magnetic pole members and sleeves provided along peripheries of the fixed magnetic pole members and rotating thereabout, for feeding the developer composed of magnetic carriers and magnetic toners to the latent image carrier. The apparatus further includes a developing chamber having a partition wall formed along the developing roller and assuming a configuration adapted to a shape of the developing roller, and a toner supply port for supplying the magnetic toners to the developing chamber from the toner accommodating chamber.
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: December 1, 1998
    Assignee: Fujitsu Limited
    Inventors: Akira Nagahara, Yoshio Yamaguchi, Shigenobu Utaka, Toshio Tooda, Haruyasu Watanabe, Sachio Sasaki, Mitsuhito Furukawa, Mitsuru Sato, Nobuo Kuwabara, Takefumi Takahashi
  • Patent number: 5778285
    Abstract: An image forming apparatus which collects residual toners on a latent image carrier in a developing unit. The image forming apparatus have a rotary endless latent image carrier; an image forming unit for forming an electrostatic latent image on the latent image carrier; a developing unit for developing the electrostatic latent image on the latent image carrier with a powdery developer and collecting residual toners on the latent image carrier at a same time; a transfer unit for transferring the developed image on the latent image carrier onto a sheet; a distribution member for distributing residual toners on the latent image carrier when in contact with the latent image carrier after image transfer; and a voltage supplying unit for supplying an AC voltage to the distribution member.
    Type: Grant
    Filed: June 13, 1997
    Date of Patent: July 7, 1998
    Assignee: Fujitsu Limited
    Inventors: Akira Nagahara, Sachio Sasaki, Mitsuhito Furukawa, Shigenobu Utaka, Yoshio Yamaguchi, Mitsuru Sato, Nobuo Kuwabara, Haruyasu Watanabe, Takefumi Takahashi
  • Patent number: 5678143
    Abstract: An image forming apparatus for forming an image on a sheet, including a rotary endless latent image carrier, an image forming device for forming an electrostatic latent image on a latent image carrier, a developing device for developing the electrostatic latent image on the latent image carrier with powdery developers and collecting residual toners on the latent image carrier at the same time, a transfer device for transferring a developed image on the latent image carrier onto a sheet, a distribution roller having independent foam perforations for distributing residual toners on the latent image carrier when in contact with the latent image carrier after image transfer, and a power supply for supplying an AC voltage to the distribution member. The distribution member is made of a conductive foam member having a pore at a surface contacting with the latent image carrier and the roller rotates in a direction opposite to a rotational direction of the latent image carrier at a peripheral velocity of 1.1 to 1.
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: October 14, 1997
    Assignee: Fujitsu Limited
    Inventors: Akira Nagahara, Sachio Sasaki, Mitsuhito Furukawa, Shigenobu Utaka, Yoshio Yamaguchi, Mitsuru Sato, Nobuo Kuwabara, Haruyasu Watanabe, Takefumi Takahashi
  • Patent number: 5587774
    Abstract: An imaging device for use in an electrographic imaging process, without a cleaning unit for residual toners, which comprises an image-carrying element, an image exposure means, a developing means, an image transfer means, and a distribution roller means of an elastic and electrically conductive material for uniformly distributing the residual toners over a surface of the image-carrying element and at the same time deelectrifying and recharging the same surface of said element. The imaging device has a simplified and compact structure and does not cause an environmental pollution problem due to the generation of ozone in the device.
    Type: Grant
    Filed: May 4, 1995
    Date of Patent: December 24, 1996
    Assignee: Fujitsu Limited
    Inventors: Akira Nagahara, Sachio Sasaki, Mitsuhito Furukawa, Tsuneo Watanuki, Norio Sawatari, Mikio Amaya, Toshiaki Narusawa
  • Patent number: 5572298
    Abstract: Disclosed is an image forming apparatus capable of performing an image forming operation in both a horizontal position and an upright position. This image forming apparatus comprises a rotary endless latent image carrier; image forming unit for forming an electrostatic latent image on the latent image carrier; developing unit for developing the electrostatic latent image on the latent image carrier with a powdery developer, the developing unit having a developing room, developing rollers provided in the developing room for supplying the powdery developer to the latent image carrier, a toner supply room for supplying toners, toner supply roller provided in the toner supply room and rotatable to supply the toners to the developing room, and a partition member for partitioning the developing room and the toner supply room and forming a toner supply passage for supplying the toners to the developing room; and transfer unit for transferring the developed image on the latent image carrier to a sheet.
    Type: Grant
    Filed: March 8, 1995
    Date of Patent: November 5, 1996
    Assignee: Fujitsu Limited
    Inventors: Akira Nagahara, Sachio Sasaki, Mitsuru Sato, Shigenobu Utaka, Takefumi Takahashi, Masahiro Wanou, Masao Konishi
  • Patent number: 5495325
    Abstract: Disclosed are an image forming method that removes adhered material from a latent image carrier and then forms an image on the latent image carrier, and an image forming apparatus that employs this method. The image forming apparatus includes: a developing unit for developing the latent image on the image carrier by toner and for collecting residual toner on the carrier; a transfer unit for transferring to the developed image a sheet; a removing mechanism for removing material that adheres to the carrier; a drive mechanism for rotating the carrier; and a controller for selectively executing an image forming mode, to control the individual constituent units, and an adhered material removal mode, to permit the removing mechanism to remove the material that adheres to the carrier as it is rotated by the drive mechanism.
    Type: Grant
    Filed: September 7, 1993
    Date of Patent: February 27, 1996
    Assignee: Fujitsu Limited
    Inventor: Akira Nagahara
  • Patent number: 5467176
    Abstract: An electrostatic latent image is developed on a latent image carrier and residual toners are collected at the same time. An electrostatic latent image is formed on a rotary endless latent image carrier; developer, including magnetic toners and magnetic carriers, is supplied to a developing area for developing the latent image carrier, and a magnetic brush is formed with the developer in the developing area to thereby collect residual toners on the latent image carrier and develop the electrostatic latent image on the latent image carrier; and the developed image on the latent image carrier is transferred to a sheet.
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: November 14, 1995
    Assignee: Fujitsu Limited
    Inventors: Tsuneo Watanuki, Yasushige Nakamura, Satoshi Takezawa, Norio Sawatari, Akira Nagahara, Sachio Sasaki, Mitsuru Sato, Shigenobu Utaka, Takefumi Takahashi, Masahiro Wanou, Masao Konishi
  • Patent number: 5448341
    Abstract: Disclosed is an image forming apparatus capable of performing an image forming operation in both a horizontal position and an upright position. This image forming apparatus comprises a rotary endless latent image carrier; image forming unit for forming an electrostatic latent image on the latent image carrier; developing unit for developing the electrostatic latent image on the latent image carrier with a powdery developer, the developing unit having a developing room, a developing roller provided in the developing room for supplying the powdery developer to the latent image carrier, a toner supply room for supplying toners, toner supply roller provided in the toner supply room and rotatable to supply the toners to the developing room, and a partition member for partitioning the developing room and the toner supply room and forming a toner supply passage for supplying the toners to the developing room; and transfer unit for transferring the developed image on the latent image carrier to a sheet.
    Type: Grant
    Filed: March 30, 1994
    Date of Patent: September 5, 1995
    Assignee: Fujitsu Limited
    Inventors: Akira Nagahara, Sachio Sasaki, Mitsuru Sato, Shigenobu Utaka, Takefumi Takahashi, Masahiro Wanou, Masao Konishi
  • Patent number: 5424489
    Abstract: A magnetic brush developing apparatus includes a development container containing a developer. A magnet is stationarily located in the development container and has magnetic poles radially provided on a plurality of points. A rotational sleeve is arranged to cover the outer circumference of the magnet and is rotatably driven to carry the developer in the development container. A blade is arranged opposite to the rotational sleeve to restrict the amount of the developer which is carried by the rotational sleeve. To obtain a uniform image quality without unevenness among different developing apparatus and a wider range of assembling precision to thus facilitate the installment of the apparatus, at a position facing the developer restriction member, and in its vicinity, there is formed a uniform magnetic flux density section having a magnetic flux density whose vertical component is substantially uniform on the periphery of the rotational sleeve.
    Type: Grant
    Filed: June 3, 1994
    Date of Patent: June 13, 1995
    Assignee: Fujitsu Limited
    Inventors: Kunihiko Sato, Sachio Sasaki, Akira Nagahara, Shin Araki, Hideaki Iwasaki
  • Patent number: 5396026
    Abstract: A magnetic brush developing apparatus, comprising: a development container (102) for containing a developer; a magnet (122) stationarily located in the development container and having magnetic poles radially provided on a plurality of points; a rotational sleeve (121) arranged to cover the outer circumference of the magnet and rotatably driven to carry the developer in the development container to an image carrying body (131); and a blade (123) arranged opposite to the sleeve to restrict the amount of the developer which is carried by the sleeve. Two of the magnetic poles are a developing magnetic pole (Pd) facing opposite to the image carrying body (131) and a developer transfer magnetic pole (Pt) located between the developing magnetic pole (Pd) and the blade (123). A magnetic brush of the developer formed on the sleeve (121) by the developer carrying magnetic pole (Pt) has a magnetic flux density.
    Type: Grant
    Filed: September 28, 1993
    Date of Patent: March 7, 1995
    Assignee: Fujitsu Limited
    Inventors: Kunihiko Sato, Sachio Sasaki, Akira Nagahara, Shin Araki, Hideaki Iwasaki, Kenji Fuke, Futoshi Okabayashi, Takamasa Araki