Patents by Inventor Hajime Kohama

Hajime Kohama 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).

  • Non-ferrous metal mechanical part
    Patent number: 4908261
    Abstract: A non-ferrous metal mechanical part having a wear-resistant and smooth surface, and comprising a substrate of a metal selected from the group consisting of aluminum, aluminum alloy, nickel, and nickel alloy, and a surface layer formed on a surface of said substrate and containing chromium oxide (Cr.sub.2 O.sub.3) as a major constituent. The chromium oxide (Cr.sub.2 O.sub.3) is a substance which has been converted by heating a chromium compound, and an intermediate layer containing a reaction product between the substrate and chromium oxide in the surface layer is formed at an interface between the surface layer and the substrate.
    Type: Grant
    Filed: September 30, 1988
    Date of Patent: March 13, 1990
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Ishii, Hisao Yabe, Hajime Kohama
  • Mechanical part
    Patent number: 4853284
    Abstract: A mechanical part brought into contact with a member selected from the group consisting of paper, rubber, plastics, resin, ceramics, and metal, comprises a substrate of an iron series metal and a surface layer formed on a surface of the substrate and containing chromium oxide (Cr.sub.2 O.sub.3) as a major constituent. The chromium oxide (Cr.sub.2 O.sub.3) is a material converted by heating a chromium compound, and an intermediate layer containing a reaction product between the substrate and chromium oxide in the surface layer is formed at an interface between the surface layer and the substrate.
    Type: Grant
    Filed: February 26, 1987
    Date of Patent: August 1, 1989
    Assignee: Kabushiki Kaisha Toshiba
    Inventors: Takashi Ishii, Hajime Kohama, Hisao Yabe
  • Method for directly bonding ceramic and metal members and laminated body of the same
    Patent number: 4849292
    Abstract: A laminated body comprising a ceramic member and a metal member, and a method of forming the laminated body are described. The laminated body is characterized in that the ceramic member contains in its surface portion a bonding agent and the metal member is directly bonded to the surface of the ceramic member. The method of forming the laminated body is characterized in that a bonding agent-containing layer is first formed in the surface of the ceramic member and then the bonding agent-containing layer is heated while being contacted with the metal member.
    Type: Grant
    Filed: April 22, 1987
    Date of Patent: July 18, 1989
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Nobuyuki Mizunoya, Hajime Kohama, Yasuyuki Sugiura
  • Machine parts with wear-resistant surface brought into contact with elongated fibrous member
    Patent number: 4822662
    Abstract: Machine parts to be brought into contact with an elongated fibrous member each consists of a substrate of an iron series metal and a surface layer which has high wear-resistance and a good sliding property, and which contains chromium oxide as a major constituent. The chromium oxide is converted from a chromium compound upon heating. An intermediate layer containing a reaction product between the chromium oxide in the surface layer and the substrate is formed at an interface between the surface layer and the substrate.
    Type: Grant
    Filed: April 15, 1986
    Date of Patent: April 18, 1989
    Assignees: Kabushiki Kaisha Toshiba, Yano Kousakujo Corporation, Notoshiti Corporation
    Inventors: Takashi Ishii, Hajime Kohama, Hisao Yabe, Akira Yano, Shinsuke Noto
  • Method for directly bonding ceramic and metal members and laminated body of the same
    Patent number: 4693409
    Abstract: A laminated body comprising a ceramic member and a metal member, and a method of forming the laminated body are described. The laminated body is characterized in that the ceramic member contains in its surface portion a bonding agent and the metal member is directly bonded to the surface of the ceramic member. The method of forming the laminated body is characterized in that a bonding agent-containing layer is first formed in the surface of the ceramic member and then the bonding agent-containing layer is heated while being contacted with the metal member.
    Type: Grant
    Filed: February 4, 1985
    Date of Patent: September 15, 1987
    Assignee: Tokyo Shibarua Denki Kabushiki Kaisha
    Inventors: Nobuyuki Mizunoya, Hajime Kohama, Yasuyuki Sugiura
  • Substrate for semiconductor modules and method of manufacture
    Patent number: 4540462
    Abstract: A method for manufacturing a semiconductor substrate. A copper sheet is placed on a surface of a ceramic plate and bonded thereto. A circuit pattern is then formed on the copper sheet by an etching process.
    Type: Grant
    Filed: December 6, 1983
    Date of Patent: September 10, 1985
    Assignee: Tokyo Shibaura Denki Kabushiki Kaisha
    Inventors: Nobuyuki Mizunoya, Hajime Kohama, Yasuyuki Sugiura