Patents by Inventor Naoki Terakado

Naoki Terakado 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: 8007716
    Abstract: A steel wire has tempered martensite, comprises, as essential components, by mass, C: 0.53 to 0.68%; Si: 1.2 to 2.5%; Mn: 0.2 to 1.5%; Cr: 1.4 to 2.5%; Al: 0.05% or less; further comprises, as a selective component, Ni: 0.4% or less; V: 0.4% or less; Mo: 0.05 to 0.5%; or Nb: 0.05 to 0.5%; and further comprises remainder essentially consisting of Fe and inevitable impurities, wherein the grain size number of prior austenite is 11.0 or larger, and the proof stress ratio (?0.2/?B), namely, a ratio of 0.2% proof stress (?0.2) to tensile strength (?B) is 0.85 or lower. Satisfying the above requirements makes it possible to produce a steel wire for high-strength spring excellent both in workability (cold workability), and in sag resistance and fatigue properties.
    Type: Grant
    Filed: March 25, 2004
    Date of Patent: August 30, 2011
    Assignees: Kabushiki Kaisha Kobe Seiko Sho, NHK Spring Co., Ltd., Shinko Wire Co., Ltd.
    Inventors: Sumie Suda, Nobuhiko Ibaraki, Noritoshi Takamura, Naoki Terakado, Satoru Tendo, Tadayoshi Fujiwara, Tetsuo Jinbo
  • Publication number: 20060201588
    Abstract: A steel wire has tempered martensite, comprises, as essential components, by mass, C: 0.53 to 0.68%; Si: 1.2 to 2.5%; Mn: 0.2 to 1.5%; Cr: 1.4 to 2.5%; Al: 0.05% or less; further comprises, as a selective component, Ni: 0.4% or less; V: 0.4% or less; Mo: 0.05 to 0.5%; or Nb: 0.05 to 0.5%; and further comprises remainder essentially consisting of Fe and inevitable impurities, wherein the grain size number of prior austenite is 11.0 or larger, and the proof stress ratio (?0.2/?B), namely, a ratio of 0.2% proof stress (?0.2) to tensile strength (?B) is 0.85 or lower. Satisfying the above requirements makes it possible to produce a steel wire for high-strength spring excellent both in workability (cold workability), and in sag resistance and fatigue properties.
    Type: Application
    Filed: March 25, 2004
    Publication date: September 14, 2006
    Inventors: Sumie Suda, Nobuhiko Ibaraki, Noritoshi Takamura, Naoki Terakado, Satoru Tendo, Tadayoshi Fujiwara, Tetsuo Jinbo
  • Patent number: 4909866
    Abstract: A high strength spring is made of steel of which composition consists of 0.6 to 0.7 wt % of C, 1.2 to 1.6 wt % of Si, 0.5 to 0.8 wt % of Mn, 0.5 to 0.8 wt % of Cr, 0.05 to 0.2 wt % in total of one or more than one of V, Mo, Nb and Ta and the balance of Fe and inevitable impurities. The steel is limited in particle size of non-metallic inclusions in such a way that the maximum particle size of the non-metallic inclusions is equal to or smaller than 15 .mu.m. The spring is applied at a portion adjacent the outer surface thereof with a residual compression stress in such a way that the maximum of the residual compression stress ranges from 85 to 110 Kgf/mm.sup.2. The spring is further process so as to have such a surface roughness that is equal to or smaller than 15 .mu.m.
    Type: Grant
    Filed: September 22, 1988
    Date of Patent: March 20, 1990
    Assignees: Nissan Motor Co., Ltd., NHK Spring Co., Ltd.
    Inventors: Makoto Abe, Tetsuyuki Taniguchi, Tsuyoshi Kuriki, Noritoshi Takamura, Naoki Terakado, Kaoru Hatayama