Patents by Inventor Kiyosumi Kanazawa

Kiyosumi Kanazawa 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: 6416636
    Abstract: The present invention is directed to an MR element and a thin film magnetic head that do not cause an increase in the electrical resistance value due to the presence of dead zones. When forming passive areas that include magnetic domain control films and conductive films at the two sides of a central active area through a vacuum film formation method, the magnetic domain control films are formed under film forming conditions that are different from the film forming conditions under which the conductive films are formed to ensure that the degree to which the conductive films overlap the central active area is set larger than the degree to which the magnetic domain control films overlap the central active area.
    Type: Grant
    Filed: January 13, 2000
    Date of Patent: July 9, 2002
    Assignee: TDK Corporation
    Inventors: Kiyosumi Kanazawa, Yoshiro Nakagawa
  • Publication number: 20010053043
    Abstract: The present invention is directed to an MR element and a thin film magnetic head that do not cause an increase in the electrical resistance value due to the presence of dead zones. When forming passive areas that include magnetic domain control films and conductive films at the two sides of a central active area through a vacuum film formation method, the magnetic domain control films are formed under film forming conditions that are different from the film forming conditions under which the conductive films are formed to ensure that the degree to which the conductive films overlap the central active area is set larger than the degree to which the magnetic domain control films overlap the central active area.
    Type: Application
    Filed: January 13, 2000
    Publication date: December 20, 2001
    Inventors: Kiyosumi Kanazawa, Yoshiro Nakagawa
  • Patent number: 6040962
    Abstract: The present invention is directed to an MR element and a thin film magnetic head that do not cause an increase in the electrical resistance value due to the presence of dead zones. When forming passive areas that include magnetic domain control films and conductive films at the two sides of a central active area through a vacuum film formation method, the magnetic domain control films are formed under film forming conditions that are different from the film forming conditions under which the conductive films are formed to ensure that the degree to which the conductive films overlap the central active area is set larger than the degree to which the magnetic domain control films overlap the central active area.
    Type: Grant
    Filed: May 14, 1998
    Date of Patent: March 21, 2000
    Assignee: TDK Corporation
    Inventors: Kiyosumi Kanazawa, Yoshiro Nakagawa
  • Patent number: 5774309
    Abstract: A central active area includes a MR film, a nonmagnetic spacer film and a soft magnetic film with the MR film constituting the lowermost layer on top of a supporting body, the nonmagnetic spacer film laminated on top of the MR film and the soft magnetic film laminated on top of the nonmagnetic spacer film to provide a lateral bias field to the MR film. A magnetic transducer and a thin film magnetic head with which the main peak width in the off track characteristics can be increased and, consequently, the margin can be increased are provided.
    Type: Grant
    Filed: March 25, 1997
    Date of Patent: June 30, 1998
    Assignee: TDK Corporation
    Inventors: Yasufumi Uno, Kiyosumi Kanazawa, Masato Takahashi
  • Patent number: 5061537
    Abstract: A magnetic disk comprising an annular flexible substrate and a magnetic layer on at least one substrate major surface is provided with a plastic film ring or a pair of plastic film rings along the outer periphery of the disk. The ring is adhesively secured to the disk on the substrate major surface. The ring thickness is controlled to a specific range relative to the substrate thickness, presenting a magnetic disk featuring stable operation and a minimized output variation.
    Type: Grant
    Filed: May 31, 1989
    Date of Patent: October 29, 1991
    Assignee: TDK Corporation
    Inventors: Yukari Kobayashi, Kiyosumi Kanazawa
  • Patent number: 4609588
    Abstract: A magnetic recording medium comprises a magnetic layer coated on a substrate and composed of ferromagnetic powder dispersed in a binder, wherein the magnetic layer contains TiO.sub.2 having an average particle size of at most 8 .mu.m and a surface area of at most 25 m.sup.2 /g as measured by a nitrogen adsorption method, and Al.sub.2 O.sub.3 having an average particle size of at least 0.1 .mu.m and a surface area of at most 30 m.sup.2 /g as measured by a nitrogen adsorption method.
    Type: Grant
    Filed: May 10, 1983
    Date of Patent: September 2, 1986
    Assignee: TDK Corporation
    Inventors: Akihiko Hosaka, Kiyotaka Okuyama, Kiyosumi Kanazawa