Patents by Inventor Takao Karoake

Takao Karoake 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: 5411609
    Abstract: A section steel wire for an oil ring for use in an internal combustion engine, consisting essentially of, by weight, 0.6 to 1.5% carbon, not more than 1.5% Si, not more than 1.5% Mn, more than 20% and not more than 25% Cr, and optionally containing at least one group selected from three groups consisting of a group of at least one element of Mo and W in total amount of not more than 3% of "Mo+W/2", another group of at least one element of V and Nb in total amount of not more than 3% of "V+Nb/2" and still another group of at least one element selected from not more than 12% Co, not more than 5% Ni and not more than 5% Cu, and balance of Fe and unavoidable impurities. The section steel wire has a Vickers hardness of HV 300 to HV 450 and has a substantially H-or X-shaped cross-section. A thickness ratio of the thickness of the web portion bridging the flange portions to the total thickness (T) of the flange portions is not greater than 0.3.
    Type: Grant
    Filed: October 19, 1993
    Date of Patent: May 2, 1995
    Assignee: Hitachi Metals, Ltd.
    Inventors: Takao Karoake, Ken Nakamura, Iwao Kashiwagi