Patents by Inventor Iwao Hatakeyama

Iwao Hatakeyama 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).

  • Publication number: 20070090494
    Abstract: There is provided an insulation-coated conductor including a conductive member that has a comer potion and a non-comer portion, and an insulating resin coated around the conductive member.
    Type: Application
    Filed: October 23, 2006
    Publication date: April 26, 2007
    Applicant: Suncall Corporation
    Inventors: Motoaki Kimura, Iwao Hatakeyama, Takao Murakami
  • Patent number: 5051970
    Abstract: An overwritable magneto-optic recording system has a recording medium with a substrate, a recording magnetic film and a reproducing magnetic film deposited on the substrate. The reproducing magnetic film has a Curie temperature lower than that of the recording magnetic film, and coercive force Hc higher than that of the recording magnetic film. In a write process, a magnetic head writes data magnetically on the recording magnetic film, then, in a transfer process, an optical head (which is positioned downstream along the relative movement of the recording medium and the optical head) heats the recording medium higher than the Curie temperature of the reproducing magnetic film so that the reproducing magnetic film loses its magnetic property. During the cooling period after heating, recorded bits in the recording magnetic film are transferred to the reproducing magnetic film which restores its magnetic property.
    Type: Grant
    Filed: May 2, 1988
    Date of Patent: September 24, 1991
    Assignee: Nippon Telegraph and Telephone Corporation
    Inventors: Osamu Ishii, Koutarou Nonaka, Iwao Hatakeyama, Tetsuo Iijima
  • Patent number: 4642245
    Abstract: .gamma.-Fe.sub.2 O.sub.3 film added at least one selected from the group consisting of Pd, Au, Pt, Rh, Ag, Ru, Ir, Os as additive, especially Os are disclosed. Reduction from .alpha.-Fe.sub.2 O.sub.3 to Fe.sub.3 O.sub.4 is accelerated by additive Os to accompany to a uniform reduction and increased the ratio of magnetic phase in the film. .gamma.-Fe.sub.2 O.sub.3 film medium added Os improves the saturation magnetization and increases the coercive force in proportion to amount of additive Os. Application of an external field to said film introduced magnetic anisotropy into said film, therefore said film medium improves coercive force and squareness of hysteresis loop by the grant of anisotropy. .gamma.-Fe.sub.2 O.sub.3 crystal grain is prepared by additive Os to obtained fine grain. The resultant .gamma.-Fe.sub.2 O.sub.3 film medium decreases the noise.
    Type: Grant
    Filed: May 6, 1985
    Date of Patent: February 10, 1987
    Assignee: Nippon Telegraph & Telephone Public Corporation
    Inventors: Osamu Ishii, Fumikatsu Yoshimura, Iwao Hatakeyama
  • Patent number: 4618901
    Abstract: A magnetic head for digital signal recording/reproducing (FIG. 11) having a C-ring shaped core (11.1) with a gap (G) for introducing leakage flux of a recording medium, a conductor (11.2, Y) for generating bias flux in hard magnetization axis of the core (11.1), apparatus (10.3, 11.3) for illuminating the core (11.1) with polarized optical beam, apparatus (11.4) for analyzing beam reflected by the core to convert polarization rotation to optical strength, and photo-detector (12.5) for providing electrical output signal relating to optical strength. The core is small enough to have a single magnetic domain, and is magnetized in the whole area because of the presence of the bias flux in spite of weak leakage signal flux, thus, the core has the capability to amplify signal flux, thus, the present head has high sensitivity and is capable of detecting flux in small area to be used for high density recording higher than 8000 bits/mm.
    Type: Grant
    Filed: July 19, 1983
    Date of Patent: October 21, 1986
    Assignee: Nippon Telegraph & Telephone Public Corporation
    Inventors: Iwao Hatakeyama, Yasushi Maeda, Osamu Ishii, Shizuka Yoshii
  • Patent number: 4544612
    Abstract: .gamma.-Fe.sub.2 O.sub.3 film with at least one additive selected from the group consisting of Pd, Au, Pt, Rh, Ag, Ru, Ir, and Os, especially Os are disclosed. Reduction from .alpha.-Fe.sub.2 O.sub.3 to Fe.sub.3 O.sub.4 is accelerated by additive Os to achieve a uniform reduction and increase the ratio of magnetic phase in the film. .gamma.-Fe.sub.2 O.sub.3 film medium with Os improved saturation magnetization and increased coercive force in proportion to amount of additive Os. Application of an external field to said film introduces magnetic anisotropy into said film, therefore said film medium improves coercive force and squareness of hysteresis loop by the introduction of anisotropy. .gamma.-Fe.sub.2 O.sub.3 crystal grain is prepared by additive Os to obtain fine grain. The resultant .gamma.-Fe.sub.2 O.sub.3 film medium a decreased noise level.
    Type: Grant
    Filed: September 16, 1983
    Date of Patent: October 1, 1985
    Assignee: Nippon Telegraph & Telephone Public Corporation
    Inventors: Osamu Ishii, Fumikatsu Yoshimura, Iwao Hatakeyama