Patents by Inventor Kazahiko Watanabe

Kazahiko Watanabe 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: 7295788
    Abstract: An image forming apparatus includes an object to be charged whose surface moves. A charging device for charging the object uses an electrical discharge generated by applying a voltage including an alternating current component to a charging member provided in contact with or in proximity to the object. A latent image forming device forms an electrostatic latent image on the surface of the object. A developing device causes a two-component developer to come into contact with the image portion of the electrostatic latent image formed by the latent image forming device and affixes toner thereto. A protective substance is present on the surface of the object in the discharge region for charging the object, and the saturation magnetization of the carrier of the two-component developer with respect to an applied magnetic field of 1000 oersted is 40 to 80 emu/g.
    Type: Grant
    Filed: April 25, 2005
    Date of Patent: November 13, 2007
    Assignee: Ricoh Company, Ltd.
    Inventors: Hiroshi Nakai, Yasuo Suzuki, Nozomu Tamoto, Takahiko Tokumasu, Kazahiko Watanabe, Kohichi Ohshima, Noboru Tsukude, Nekka Matsuura, Hiroshi Ikuno
  • Publication number: 20050244176
    Abstract: In an image forming apparatus that employs a system of charging by adjacent discharge, not only can degradation of the photoreceptor surface caused by adjacent discharge be prevented, but also there is no side effect on the developer, and at the same time size reduction is achieved. The image forming apparatus comprises an object to be charged whose surface moves; a charging device for charging the object to be charged using an electrical discharge generated by applying a voltage comprising an alternating current component to a charging member provided in contact with or in proximity to the object to be charged; a latent image forming device for forming an electrostatic latent image on the surface of the object charged by the charging device; and a developing device for causing a two-component developer to come into contact with the image portion of the electrostatic latent image formed by the latent image forming device and affixing toner thereto.
    Type: Application
    Filed: April 25, 2005
    Publication date: November 3, 2005
    Inventors: Hiroshi Nakai, Yasuo Suzuki, Nozomu Tamoto, Takahiko Tokumasu, Kazahiko Watanabe, Kohichi Ohshima, Noboru Tsukude, Nekka Matsuura, Hiroshi Ikuno