Patents by Inventor Shinichi Tsunashima

Shinichi Tsunashima 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: 6767134
    Abstract: The contact portion of the end face of a conical roller, which is a portion to be slidingly contacted with a collar portion, is ground such that the outer contour line of the section thereof has a continuously curved line which passes through at least not only the first point but also between the third position and fourth position.
    Type: Grant
    Filed: July 3, 2002
    Date of Patent: July 27, 2004
    Assignee: NSK Ltd.
    Inventors: Takashi Murai, Shinichi Tsunashima, Osamu Fujii
  • Patent number: 6712520
    Abstract: A cage is made of a low carbon steel and is for use in a rolling bearing which includes an outer ring, an inner ring and a plurality of rolling elements disposed rotationally between the outer ring and the inner ring. The cage includes a plurality of pockets for retaining the rolling elements in an equi-distribution in the rotating direction of the rolling elements. The low carbon steel is a steel containing from 0.02 to 0.10% by weight of C and from 0.10 to 0.45% by weight of Mn and is subjected to plastic working. The hardness for the pocket surface at least at a portion in contact with the rolling element is Hv 190 to 270, and the hardness for the core portion in the cage section is Hv 110 to 170.
    Type: Grant
    Filed: August 8, 2001
    Date of Patent: March 30, 2004
    Assignee: NSK Ltd.
    Inventors: Koji Ueda, Keijiro Yamaguchi, Shinichi Tsunashima, Takashi Murai, Osamu Fujii
  • Publication number: 20030021505
    Abstract: A cage for use in a rolling bearing made of low carbon steel for use in a rolling bearing comprising an outer ring, an inner ring and a plurality of rolling elements disposed rotationally between the outer ring and the inner ring and having pockets for retaining the rolling elements in an equi distribution in the rotating direction of the rolling element is constituted with a steel containing from 0.02 to 0.10% by weight of C and from 0.10 to 0.45% by weight of Mn, in which the hardness for the surface at least at a portion in contact with the rolling element is Hv 190 or more and the hardness for the inside is Hv 110 to 170, the cage for use in the rolling bearing described above being a high strength cage causing less deformation or fracture and having a stable performance.
    Type: Application
    Filed: August 8, 2001
    Publication date: January 30, 2003
    Inventors: Koji Ueda, Keijiro Yamaguchi, Shinichi Tsunashima, Takashi Murai, Osamu Fujii
  • Publication number: 20030012477
    Abstract: The contact portion of the end face of a conical roller, which is a portion to be slidingly contacted with a collar portion, is ground such that the outer contour line of the section thereof has a continuously curved line which passes through at least not only the first point but also between the third position and fourth position.
    Type: Application
    Filed: July 3, 2002
    Publication date: January 16, 2003
    Applicant: NSK LTD.
    Inventors: Takashi Murai, Shinichi Tsunashima, Osamu Fujii
  • Patent number: 6203205
    Abstract: A cylindrical roller bearing comprises an inner race, an outer race, a plurality of cylindrical rollers disposed between the inner race and the outer race, and a cage disposed between the inner race and the outer race and provided with pocket portions in which the plurality of cylindrical rollers are respectively accommodated. The cylindrical roller bearing satisfies a following relations 1.5×10−3D≦H≦9.0×10−3D and A/B=0.6˜1.
    Type: Grant
    Filed: July 12, 1999
    Date of Patent: March 20, 2001
    Assignee: NSK Ltd.
    Inventors: Takashi Murai, Takashi Yamamoto, Shinichi Tsunashima
  • Patent number: RE48586
    Abstract: The contact portion of the end face of a conical roller, which is a portion to be slidingly contacted with a collar portion, is ground such that the outer contour line of the section thereof has a continuously curved line which passes through at least not only the first point but also between the third position and fourth position.
    Type: Grant
    Filed: January 22, 2019
    Date of Patent: June 8, 2021
    Assignee: NSK LTD.
    Inventors: Takashi Murai, Shinichi Tsunashima, Osamu Fujii