Patents by Inventor Keiichi FUJIE

Keiichi FUJIE 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).

  • Steel for spring, and method for producing spring
    Patent number: 10041160
    Abstract: Provided is high strength steel for springs that, compared to conventional high strength steel for springs, has excellent decarburization resistance and scale exfoliation property, by optimization of the added amounts of C, Si, Mn, and Cr as well as of Sb and Sn. The steel for springs contains C: more than 0.45 mass % and less than 0.65 mass %, Si: 0.15 mass % or more and 0.70 mass % or less, Mn: 0.10 mass % or more and 1.00 mass % or less, Cr: 0.20 mass % or more and 1.50 mass % or less, P: 0.025 mass % or less, S: 0.025 mass % or less, O: 0.0015 mass % or less, Sb: 0.010 mass % or more and less than 0.030 mass %, and Sn: 0.010 mass % or more and 0.030 mass % or less, under predetermined conditions.
    Type: Grant
    Filed: September 11, 2014
    Date of Patent: August 7, 2018
    Assignees: JFE STEEL CORPORATION, SUMIHATSU CO., LTD., NHK SPRING CO., LTD.
    Inventors: Minoru Honjo, Kiyoshi Uwai, Shigeru Endo, Katsutoshi Yamashita, Koei Tsuru, Keiichi Fujie, Akira Tange
  • STEEL FOR SPRING, AND METHOD FOR PRODUCING SPRING
    Publication number: 20160222497
    Abstract: Provided is high strength steel for springs that, compared to conventional high strength steel for springs, has excellent decarburization resistance and scale exfoliation property, by optimization of the added amounts of C, Si, Mn, and Cr as well as of Sb and Sn. The steel for springs contains C: more than 0.45 mass % and less than 0.65 mass %, Si: 0.15 mass % or more and 0.70 mass % or less, Mn: 0.10 mass % or more and 1.00 mass % or less, Cr: 0.20 mass % or more and 1.50 mass % or less, P: 0.025 mass % or less, S: 0.025 mass % or less, O: 0.0015 mass % or less, Sb: 0.010 mass % or more and less than 0.030 mass %, and Sn: 0.010 mass % or more and 0.030 mass % or less, under predetermined conditions.
    Type: Application
    Filed: September 11, 2014
    Publication date: August 4, 2016
    Applicants: JFE STEEL CORPORATION, SUMIHATSU CO., LTD., NHK SPRING CO., LTD.
    Inventors: Minoru HONJO, Kiyoshi UWAI, Shigeru ENDO, Katsutoshi YAMASHITA, Koei TSURU, Keiichi FUJIE, Akira TANGE