Patents by Inventor Shigeo Koyama

Shigeo Koyama 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: 4468111
    Abstract: An electrostatic copying machine apparatus includes a developing device having a fixedly positioned permanent magnet and a hollow developing sleeve formed of a non-magnetic material mounted coaxially about the permanent magnet for rotation thereabout. Toner supplied to the periphery of the sleeve forms thereon a magnetic brush which is conveyed by rotation of the sleeve to a developing position whereat the toner is transferred to a photoreceptor as a visible toner image. A bristle cutting member is positioned upstream of the developing position to restrict the length of the magnetic brush. A blade member formed of a non-magnetizable material prevents solidification of the toner on the periphery of the sleeve and is positioned upstream of the bristle cutting member. The blade member slides in contact with the periphery of the sleeve at a scraping position. The permanent magnet has spaced therearound at equal circumferential intervals a plurality of magnetizing positions having magnetic poles.
    Type: Grant
    Filed: August 18, 1982
    Date of Patent: August 28, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Ryutaro Yamagata, Nobuhiko Kozuka, Hitoshi Nishihama, Shigeo Koyama, Kazutada Sakai
  • Patent number: 4452530
    Abstract: A copying apparatus of the type in which an original-support device is mounted reciprocably on a housing through a sliding mechanism. The sliding mechanism is comprised of an outside rail fixed to one of the original-support device and the housing, an inside rail fixed to the other of said original-support device and housing, and disposed between the outside and inside rails, a holding plate rotatably holding a plurality of balls which contact both of the outside and inside rails. Each of the opposite ends of one of the outside and inside rails has disposed thereat a stop face against which each of the opposite ends of the holding plate can abut, and one end portion of the other of said outside and inside rails has disposed thereat a stop face against which one end of the holding plate can abut. A stop member defining a stop face against which the other end of the holding plate can abut is detachably disposed at the other end portion of the other of said outside and inside rails.
    Type: Grant
    Filed: August 14, 1981
    Date of Patent: June 5, 1984
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Shigeo Koyama, Ryutaro Yamagata, Nobuhiko Kozuka, Hiromi Sakato
  • Patent number: 4444494
    Abstract: An original-holding mechanism for an original-support device is disclosed which includes a flexible holding member for covering an original document placed on a transparent plate and a rigid supporting member located outwardly of the original-holding member. One end edge portion of the original-holding member is mounted adjacent to one end edge of the transparent plate. The base portion of the supporting member is mounted for pivotal movement about an axis extending along said one edge of the transparent plate as a center. The free end edge portion of the original-holding member is connected to the free end portion of the supporting member for movement over a predetermined range in a direction perpendicular to said axis.
    Type: Grant
    Filed: January 17, 1983
    Date of Patent: April 24, 1984
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Shigeo Koyama, Ryutaro Yamagata, Nobuhiko Kozuka, Hiromi Sakata
  • Patent number: 4436412
    Abstract: A cleaning device for use on a transfer type electrostatic copying apparatus includes a magnetic brush cleaning device for cleaning off a magnetizable toner remaining on a photosensitive material after a transfer operation. A brush roller is disposed between the magnetic brush cleaning device and a transfer zone. A brush is arranged on a peripheral surface of a cylindrical sleeve of light transmitting material and is driven for rotation in contact with the photosensitive material. A charge eraser lamp is secured within the cylindrical sleeve. The charge on the photosensitive material or photoreceptor is almost completely erased, and consequently, the cleaning efficiency is markedly improved owing to the facilitated removal of the developing material by the magnetic brush.
    Type: Grant
    Filed: May 20, 1981
    Date of Patent: March 13, 1984
    Assignee: Mita Industrial Company Limited
    Inventors: Ryutaro Yamagata, Nobuhiko Kozuka, Hitoshi Nishihama, Shigeo Koyama, Kazutada Sakai
  • Patent number: 4410259
    Abstract: An apparatus for developing a latent electrostatic image, includes a developer holding member having a surface adapted for movement through an endless path and a developer receptacle having an opening formed at a site opposite to a part of the endless path. The receptacle contains a one-component developer consisting only of toner particles capable of retaining an electric charge. The developer in the receptacle is held on the surface of the developer holding member and charged by a charging member. The charged developer is carried to a developing zone by the movement of the surface of the developer holding member and applied to a latent electrostatic image to be developed.
    Type: Grant
    Filed: March 3, 1981
    Date of Patent: October 18, 1983
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Ryutaro Yamagata, Nobuhiko Kozuka, Hitoshi Nishihama, Shigeo Koyama, Kazutada Sakai
  • Patent number: 4400077
    Abstract: A photosensitive drum assembly for an electrostatic copying apparatus includes a cylindrical drum having a photosensitive layer provided around its outer periphery. The drum is held between a pair of flanges at opposite axial ends of the drum. Each of the flanges is formed having a diameter larger than the external diameter of the drum. At the edge of each flange, is a cylindrical portion extending along the axis of the drum to face toward the opposite flange. The end edges of the drum closely fit into the cylindrical portions. According to the present invention, since the edges of the drum closely fit into the cylindrical portions of the flanges, it is not necessary to improve the dimensional accuracy of the inside periphery of the opposite ends of the drum, while it is essential to improve the dimensional accuracy in a conventional manner.
    Type: Grant
    Filed: October 22, 1981
    Date of Patent: August 23, 1983
    Assignee: Mita Industrial Company Limited
    Inventors: Nobuhiko Kozuka, Ryutaro Yamagata, Shigeo Koyama, Hiromi Sakata, Atsushi Kano
  • Patent number: 4387889
    Abstract: A copying apparatus provided with a cassette-type paper feeding mechanism. The paper feeding mechanism includes a cassette-receiving section disposed at an upstream end of a paper transfer passage defined within a housing and a copying paper cassette to be mounted to the cassette-receiving section through an opening formed in a side wall of the housing and is constructed such that when the paper cassette is inserted into the cassette-receiving section through the opening of the housing to set it at an inoperative position and further moved in a predetermined direction to set it at an operative position, a paper feeding member provided in the cassette-receiving section acts on a copying paper in the paper cassette to render it ready for feeding into the paper transfer passage. A pair of paper transfer rollers are provided at that position of the paper transfer passage which is in proximity to the cassette-receiving section, and at least one of these transfer rollers is mounted movably relative to the other.
    Type: Grant
    Filed: July 29, 1981
    Date of Patent: June 14, 1983
    Assignee: Mita Industrial Co., Ltd.
    Inventors: Shigeo Koyama, Ryutaro Yamagata, Nobuhiko Kozuka, Hiromi Sakata
  • Patent number: 4259008
    Abstract: Improvements are provided in and relating to an electrostatic copying apparatus including a housing, a support for supporting an original to be copied, the support being mounted on the housing and having a transparent plate for supporting the original thereon and a holding member for covering the original on the transparent plate, a system for forming a copied image disposed within the housing and having an optical system for projecting the image of the original on the transparent plate, and a system for transferring a copying paper synchronously with the scanning of the original which is effected by the relative movement of the original holder and the optical system.
    Type: Grant
    Filed: April 10, 1979
    Date of Patent: March 31, 1981
    Assignee: Mita Industrial Company, Ltd.
    Inventors: Ryutaro Yamagata, Sohei Matsuo, Shigeo Koyama, Nobuhiko Kozuka, Yasusuke Tohi, Tatsuo Aizawa