Patents by Inventor Hazime Tazumi

Hazime Tazumi 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: 5403545
    Abstract: A bearing steel having long rolling life comprising, by weight, 0.65 to 0.90% of C, 0.15 to 0.50% of Si, 0.15 to 1.0% of Mn and 2.0 to 5.0% of Cr, and the balance of Fe. Austenite grain size can be prevented from becoming coarser to make hardening in high temperature possible by further adding one or more of 0.0090 to 0.0200% of N, 0.010 to 0.050% of Al and 0.005 to 0.500% of Nb as optional elements to the steel. Further, rolling fatigue life can be improved by further adding one or more of 0.20 to 0.50% of Ni, 0.10 to 2.00% Of Mo and 0.05 to 1.00% of V as optional elements, and machinability can be improved by further adding one or more of 0.02 to 0.05% of S, 0.005 to 0.10% of rare earth elements, 0.02 to 0.30% of Pb, 0.0005 to 0.0100% of Ca, 0.001 to 0.200% of Bi, 0.005 to 0.20% of Se and 0.005 to 0.100% of Te in the steel as optional elements.
    Type: Grant
    Filed: December 14, 1992
    Date of Patent: April 4, 1995
    Assignees: Aichi Steel Works, Ltd., Koyo Seiko K.K., Nippondenso Co., Ltd.
    Inventors: Yatsuka Takata, Akira Muroga, Yoshihiro Wakikado, Takao Ooki, Masao Goto, Hazime Tazumi, Teruo Hoshino, Masayuki Kitamura, Toshihiro Kawaguchi, Yoshitaka Natsume, Akihiro Mizutani