Patents by Inventor Toshihiko Okamura

Toshihiko Okamura 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: 5883588
    Abstract: A data compression system includes a data array storage device, a coding device, a retrieving and recording device and a recording controller. The data array storage device stores both the input data to be compressed and the input data coded by the coding device. The recording controller determines the character strings recorded by the retrieving and recording device by discriminating between character strings on the basis of the length of the matched character strings beginning from an intermediate character of the matched character strings. The coding device then codes the matched character strings using the length and position of the recorded character strings.
    Type: Grant
    Filed: October 4, 1995
    Date of Patent: March 16, 1999
    Assignee: NEC Corporation
    Inventor: Toshihiko Okamura
  • Patent number: 5660881
    Abstract: This invention presents diamond coated tool member of high toughness exhibiting excellent diamond adhesion to the substrate. The green compacts of the usual Co and WC composition are subjected to primary sintering in a vacuum or in an inert gas atmosphere, followed by secondary sintering in a vacuum or in an inert gas atmosphere at a pressure in the range of 10-200 atmospheres at a temperature between the liquid formation temperature of Co and 1,500.degree. C. The as-sintered surfaces are subjected to chemical etching, followed by fine polishing in an ultrasonic bath held at room temperature or a temperature just below the boiling point. The cutting tool substrate having the polished surface is placed in a CVD reactor to deposit a diamond coating. The concentration profile of Co in the diamond coated tool member hus formed has a Co-deficient layer and a Co-gradient layer.
    Type: Grant
    Filed: June 6, 1995
    Date of Patent: August 26, 1997
    Assignee: Mitsubishi Materials Corporation
    Inventor: Toshihiko Okamura
  • Patent number: 5618625
    Abstract: This invention presents diamond coated tool member of high toughness exhibiting excellent diamond adhesion to the substrate. The green compacts of the usual Co and WC composition are subjected to primary sintering in a vacuum or in an inert gas atmosphere, followed by secondary sintering in a vacuum or in an inert gas atmosphere at a pressure in the range of 10-200 atmospheres at a temperature between the liquid formation temperature of Co and 1,500.degree. C. The as-sintered surfaces are subjected to chemical etching, followed by fine polishing in an ultrasonic bath held at room temperature or a temperature just below the boiling point. The cutting tool substrate having the polished surface is placed in a CVD reactor to deposit a diamond coating. The concentration profile of Co in the diamond coated tool member hus formed has a Co-deficient layer and a Co-gradient layer.
    Type: Grant
    Filed: February 14, 1994
    Date of Patent: April 8, 1997
    Assignee: Mitsubishi Materials Corporation
    Inventor: Toshihiko Okamura
  • Patent number: 5068148
    Abstract: A tool member includes a tungsten carbide based cemented carbide substrate and a diamond coating deposited on the substrate. The substrate has two diffraction peaks K.alpha..sub.1 and K.alpha..sub.2 indexed by index of pane (211) for tungsten carbide in X-ray diffraction. The peaks satisfy the relationship of 1.sub.1 /1.sub.2 .ltoreq.35, where 1.sub.1 and 1.sub.2 are heights of the peaks K.alpha..sub.1 and K.alpha..sub.2 measured from a base of a trough between the two diffraction peaks. For manufacturing the tool member, a green compact is first sintered to provide a tungsten carbide based cemented carbide substrate. Subsequently the substrate is ground and subsequently heat-treated at a temperature between 1000.degree. C. and 1600.degree. C. in a vacuum or in a non-oxidizing atmosphere. Thereafter, a diamond coating is formed on the substrate by vapor-deposition method.
    Type: Grant
    Filed: December 21, 1989
    Date of Patent: November 26, 1991
    Assignee: Mitsubishi Metal Corporation
    Inventors: Kei Nakahara, Keiichi Sakurai, Toshihiko Okamura, Hironori Yoshimura, Hiroyuki Eto, Noribumi Kikuchi
  • Patent number: 4433259
    Abstract: An electric rotating machine can be constructed by mass production techniques, can sustain large axial loads, and can be formed out of a portion of the chassis of a portable electronic device. The electric rotating machine, which can be a duplex micromotor, comprises a base plate, at least one rotor assembly each including a rotor shaft, a rotor magnet disposed on the shaft and having radial pole faces, a pair of bearings supporting opposite ends of the shaft, and a worm, spur gear, or other such element situated on the shaft. A field yoke is favorably formed as a box-like structure of magnetic material with a field magnet therein having pole faces facing radially towards the rotor magnet. The field yoke has an open side mating with the base plate. Upstanding ears are formed on the base plate to seat the rotor bearings when the latter are inserted therein in an assembly direction perpendicular to the axis of the rotor shaft.
    Type: Grant
    Filed: December 17, 1981
    Date of Patent: February 21, 1984
    Assignee: Sony Corporation
    Inventor: Toshihiko Okamura
  • Patent number: 4417167
    Abstract: In a DC brushless motor including a rotor assembly having permanent magnets and a stator assembly having coils arranged in the magnetic field generated by the permanent magnets of the rotor assembly, with the energization of the coils being controlled so as to impart a rotational torque to the rotor assembly; the permanent magnets of the rotor assembly are flat and are attached to a rotor yoke, which can be constructed as an octagonal prism, to provide a path for the magnetic flux emanating from the magnets and to support the flat magnets so that the latter form substantially a regular polygon in cross section. The magnets can be arranged with their poles in a north-south-north-south sequence against flat side walls of the rotor yoke to provide a flux density pattern that is substantially sinusoidal.
    Type: Grant
    Filed: December 11, 1981
    Date of Patent: November 22, 1983
    Assignee: Sony Corporation
    Inventors: Hirohisa Ishii, Masami Shishikura, Toshihiko Okamura