Patents by Inventor Keiji Yasufuku

Keiji Yasufuku 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).

  • Heavy duty tire including narrow circumferential grooves
    Patent number: 5524686
    Abstract: A heavy duty tire having an improved tread wear resistance, which comprises a tread portion provided on each side of the tire equator with a wide circumferential groove and a narrow circumferential groove. The wide circumferential groove is spaced apart from the tire equator by an axial distance of 15 to 25% of the tread width. The narrow circumferential groove is disposed on the axially inside of the wide circumferential groove and spaced apart from the axially inner groove edge of the wide circumferential groove by an axial distance of 0.02 to 0.05 times the tread width. The depth of the wide circumferential groove is in the range of 0.05 to 0.08 times the tread width. The depth of the narrow circumferential groove is in the range of 0.7 to 1.0 times the depth of the wide circumferential groove. The groove width of the narrow circumferential groove is in the range of 1.5 to 2.5 mm.
    Type: Grant
    Filed: September 13, 1994
    Date of Patent: June 11, 1996
    Assignee: Sumitomo Rubber Industries, Ltd.
    Inventors: Yoshiyuki Takada, Keiji Yasufuku