Patents by Inventor Jiro Tominaga

Jiro Tominaga 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: 4851059
    Abstract: A non-magnetic cold-deformed stainless steel usable for electronic equipment parts has a Vickers hardness number after cold forming of not less than 400 and a magnetic permeability of not more than 1.01. The steel has excellent hot workability and is mainly used for components such as shafts and pins of VTRs and VTR cassette tapes.
    Type: Grant
    Filed: March 7, 1988
    Date of Patent: July 25, 1989
    Assignees: Nippon Steel Corp., TNK Sanwa Precision Co., Ltd.
    Inventors: Hidehiko Sumitomo, Takanori Nakazawa, Jun Nakatsuka, Jiro Tominaga, Yoshiaki Kanai
  • Patent number: 4537644
    Abstract: A high-tension high-toughness steel excellent in resistance to delayed fracture which consists essentially of 0.15 to 0.50% of C, up to 1.50% of Si, 0.20 to 1.50% of Mn, up to 2.00% of Cr, 0.0005 to 0.0030% of B, 0.005 to 0.10% of acid-soluble Al, up to 0.010% of P, up to 0.0020% of N, 0.010 to 0.050% of Ti and the balance iron and inevitable impurities, and has a tempered martensitic structure obtained by quenching and tempering.
    Type: Grant
    Filed: September 21, 1982
    Date of Patent: August 27, 1985
    Assignee: Nippon Steel Corporation
    Inventors: Jiro Tominaga, Hiroshi Yada, Mitsuo Honda
  • Patent number: 4360390
    Abstract: Method for direct heat treating austenitic stainless steel wire rod wherein a hot rolled austenitic stainless steel wire rod is rendered to finish the final finishing stand of a hot rolling mill at a temperature zone in the range of solution heat treatment, then the temperature zone of said solution heat treatment is so maintained that the austenitic crystal grain size is to be less than 7.0, and subsequently said wire rod is quenched to a temperature where no chromium carbide is precipitated at a cooling rate where no chromium carbide is precipitated.
    Type: Grant
    Filed: September 5, 1980
    Date of Patent: November 23, 1982
    Assignee: Nippon Steel Corporation
    Inventors: Jiro Tominaga, Wataru Shinada, Wataru Murata, Masahiro Ito
  • Patent number: 4314860
    Abstract: Method for heat treating hot rolled steel wire rod in direct sequence with the final finishing stand of a rod hot rolling mill which comprises a series of steps of subjecting the rod emerging from the rolling mill to a direct controlled cooling in the range of Ms to 550.degree. C. by utilizing the retained heat of the rod, and subsequently reheating it to a temperature as equal as the nose temperature of TTT diagram with a view to achieving the complete transformation to the sorbite structure, whereby a wire rod product having the mechanical properties equal to those of a rod resulting from the lead patenting process can be obtained.
    Type: Grant
    Filed: September 5, 1980
    Date of Patent: February 9, 1982
    Assignee: Nippon Steel Corporation
    Inventor: Jiro Tominaga