Patents by Inventor Tetsuo Shiraga

Tetsuo Shiraga 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).

  • Low carbon resulfurized free cutting steel
    Patent number: 8691141
    Abstract: A low carbon resulfurized free cutting steel consisting of 0.04 to 0.15% of C, more than 0.10% and 0.70% or less of Si, 0.85 to 1.50% of Mn, 0.040 to 0.120% of P, 0.250% or more and less than 0.400% of S, less than 0.005% of Al, more than 0.0020% and 0.0120% or less of O, and more than 0.0070% and 0.0150% or less of N, all by mass percentage, and the balance of Fe and inevitable impurities, and satisfying a formula (1) and a formula (2), as follows: 0.15%?Si %+2×P %?(5×Al %+10×O %+3×N %)?0.75%??(1), and ([Mn %]5)/15<S %<([Mn %]5)/2??(2).
    Type: Grant
    Filed: December 9, 2009
    Date of Patent: April 8, 2014
    Assignee: JFE Bars and Shapes Corporation
    Inventors: Toshiyuki Murakami, Kunikazu Tomita, Tetsuo Shiraga
  • Free cutting steel
    Patent number: 8124008
    Abstract: A low carbon free cutting steel can be obtained by allowing the steel to contain 0.02 to 0.15 mass % of C, 0.05 to 1.8 mass % of Mn, 0.20 to 0.49 mass % of S, more than 0.01 mass % and not more than 0.03 mass % of O, 0.3 to 2.3% of Cr, and the balance consisting of Fe and inevitable impurities, the Cr/S ratio falling within a range of between 2 and 6.
    Type: Grant
    Filed: November 29, 2002
    Date of Patent: February 28, 2012
    Assignees: JFE Bars & Shapes Corporation, National Institute of Advanced Industrial Science & Technology
    Inventors: Toshiyuki Murakami, Tetsuo Shiraga, Kiyohito Ishida, Katsunari Oikawa
  • LOW CARBON RESULFURIZED FREE CUTTING STEEL
    Publication number: 20110243786
    Abstract: A low carbon resulfurized free cutting steel consisting of 0.04 to 0.15% of C, more than 0.10% and 0.70% or less of Si, 0.85 to 1.50% of Mn, 0.040 to 0.120% of P, 0.250% or more and less than 0.400% of S, less than 0.005% of Al, more than 0.0020% and 0.0120% or less of O, and more than 0.0070% and 0.0150% or less of N, all by mass percentage, and the balance of Fe and inevitable impurities, and satisfying a formula (1) and a formula (2), as follows: 0.15%?Si %+2×P %?(5×Al %+10×O %+3×N %)?0.75%??(1), and ([Mn %]5)/15<S %<([Mn %]5)/2??(2).
    Type: Application
    Filed: December 9, 2009
    Publication date: October 6, 2011
    Inventors: Toshiyuki Murakami, Kunikazu Tomita, Tetsuo Shiraga
  • Free-cutting steel
    Publication number: 20040258555
    Abstract: A low carbon free cutting steel can be obtained by allowing the steel to contain 0.02 to 0.15 mass % of C, 0.05 to 1.8 mass % of Mn, 0.20 to 0.49 mass % of S, more than 0.01 mass % and not more than 0.03 mass % of O, 0.3 to 2.3% of Cr, and the balance consisting of Fe and inevitable impurities, the Cr/S ratio falling within a range of between 2 and 6.
    Type: Application
    Filed: May 17, 2004
    Publication date: December 23, 2004
    Inventors: Toshiyuki Murakami, Tetsuo Shiraga, Kiyohito Ishida, Katsunari Oikawa
  • High strength screw
    Patent number: 6558484
    Abstract: To provide a high-strength steel having a desired strength (800 N/mm2 or higher) for screws and bolts of a large diameter (M8 or larger) that also have a tapping ability, and a high-strength screw made from such a steel. The steel comprises (by % mass) C: 0.05 to 0.20, Si: 0.20 or less (not including 0), Mn: 0.5 to 2.0, P: 0.015 or less, S: 0.015 or less, sol. Al: 0.020 to 0.080, N: 0.0060 or less, Cr: more than 0.80 to 2.0 and the balance being iron and unavoidable impurities.
    Type: Grant
    Filed: March 4, 2002
    Date of Patent: May 6, 2003
    Inventors: Hiroshi Onoe, Tetsuo Shiraga, Katsuhiko Kikuchi