Patents by Inventor Tadafumi Tomitani

Tadafumi Tomitani 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: 5086553
    Abstract: A flying-type composite magnetic head includes (a) a magnetic core constituted by a pair of core pieces bonded together by a first glass portion, at least one of opposing surfaces of the core pieces being formed with a thin magnetic metal layer; (b) a non-magnetic slider having a slit for receiving the magnetic core; and (c) a second glass portion for fixing the magnetic core in the slit; the first glass portion having a softening point lower than a first bonding temperature by 70.degree. C. or more and a yielding temperature higher than a second bonding temperature, and the second glass portion having a softening point lower than a second bonding temperature by 70.degree. C. or more. The first bonding temperature T.sub.1 (.degree.C.) for forming the first glass portion satisfies the following relation:T.sub.1 .ltoreq.aW+b,wherein W is a thickness (.mu.m) of the thin magnetic metal layer, a is between -25 and -15 and b is between 720 and 770, and a second bonding temperature T.sub.
    Type: Grant
    Filed: October 31, 1990
    Date of Patent: February 11, 1992
    Assignee: Hitachi Metals, Ltd.
    Inventors: Ryo Goto, Tadafumi Tomitani, Fumio Nitanda, Masanobu Yamazaki, Manabu Toyoda, Makoto Ushijima
  • Patent number: 5016129
    Abstract: A flying-type composite magnetic head includes (a) a magnetic core constituted by a pair of core pieces bonded together by a first glass portion, at least one of opposing surfaces of the core pieces being formed with a thin magnetic metal layer; (b) a non-magnetic slider having a slit for receiving the magnetic core; and (c) a second glass portion for fixing the magnetic core in the slit; the first glass portion having a softening point lower than a first bonding temperature by 70.degree. C. or more and a yielding temperature higher than a second bonding temperature, and the second glass portion having a softening point lower than a second bonding temperature by 70.degree. C. or more. The first bonding temperature T.sub.1 .degree.C.) for forming the first glass portion satisfies the following relation:T.sub.1 .ltoreq.aW+b,wherein W is a thickness (.mu.m) of the thin magnetic metal layer, a is between -25 and -15 and b is between 720 and 770, and a second bonding temperature T.sub.
    Type: Grant
    Filed: March 29, 1989
    Date of Patent: May 14, 1991
    Assignee: Hitachi Metals, Ltd.
    Inventors: Ryo Goto, Tadafumi Tomitani, Fumio Nitanda, Masanobu Yamazaki, Manabu Toyoda, Makoto Ushijima
  • Patent number: 4999726
    Abstract: A magnetic core for a flying-type composite magnetic head, including a pair of core pieces, a glass portion for bonding the core pieces, and a thin magnetic metal layer of Fe-Al-Si alloys formed on at least one of opposing surfaces of the core pieces. The thin magnetic metal layer extends by 10 .mu.m or more from an apex of a magnetic gap defined by the core pieces and has an inner end existing by 15 .mu.m or more inside an inner end of the bonding glass portion.
    Type: Grant
    Filed: March 27, 1989
    Date of Patent: March 12, 1991
    Assignee: Hitachi Metals, Ltd.
    Inventors: Ryo Goto, Tadafumi Tomitani, Fumio Nitanda, Manabu Toyoda, Makoto Ushijima