Patents by Inventor Tomokichi Tokuda

Tomokichi Tokuda 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).

  • Press-formed product
    Patent number: 9718113
    Abstract: A press-formed product includes a body having a transverse cross section including a bottom portion and a shoulder portion contiguous to the bottom portion through an R end. In the transverse cross section, a first region from the R end to a position a distance away in a bottom portion extending direction, and a second region which is part of the bottom portion and is contiguous to the first region have a work-hardening distribution introduced by press-forming. The work-hardening distribution has an average hardness Hv1 of an area of the first region from a steel sheet surface to a depth obtained by multiplying a steel sheet thickness by 0.2 and an average hardness Hv2 of an area of the second region from the steel sheet surface to a position obtained by multiplying the steel sheet thickness by 0.2 to satisfy a relationship of Hv1>1.05×Hv2.
    Type: Grant
    Filed: December 20, 2012
    Date of Patent: August 1, 2017
    Assignees: NIPPON STEEL & SUMITOMO METAL CORPORATION, TOYODA IRON WORKS CO., LTD.
    Inventors: Masahiro Nakata, Toshiya Suzuki, Tomokichi Tokuda, Masanobu Ichikawa, Nobuyuki Ichimaru
  • PRESS-FORMED PRODUCT
    Publication number: 20140356643
    Abstract: A press-formed product includes a body having a transverse cross section including a bottom portion and a shoulder portion contiguous to the bottom portion through an R end. In the transverse cross section, a first region from the R end to a position a distance away in a bottom portion extending direction, and a second region which is part of the bottom portion and is contiguous to the first region have a work-hardening distribution introduced by press-forming. The work-hardening distribution has an average hardness Hv1 of an area of the first region from a steel sheet surface to a depth obtained by multiplying a steel sheet thickness by 0.2 and an average hardness Hv2 of an area of the second region from the steel sheet surface to a position obtained by multiplying the steel sheet thickness by 0.2 to satisfy a relationship of Hv1>1.05×Hv2.
    Type: Application
    Filed: December 20, 2012
    Publication date: December 4, 2014
    Inventors: Masahiro Nakata, Toshiya Suzuki, Tomokichi Tokuda, Masanobu Ichikawa, Nobuyuki Ichimaru