Patents by Inventor Akinari Fujita

Akinari Fujita 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).

  • Double walled pipe, jacking method and pipe end structure of leading pipe
    Patent number: 6109305
    Abstract: There is provided a double walled pipe having an inner pipe and an outer pipe which is movable relative to the inner pipe in a longitudinal direction of the inner pipe. Acting on only the outer pipe with a pipe jacking power makes it possible to bury the double walled pipe, without damaging the rear end of the inner pipe and also generating an internal stress on the inner pipe. Consequently, it is avoided such a situation that even in use pinholes, cracks, etc. occur on the inner pipe, and thus it is possible to expect an execution with higher reliability.
    Type: Grant
    Filed: August 6, 1999
    Date of Patent: August 29, 2000
    Assignees: Kawasaki Steel Corp., Tokyo Gas Co. Ltd.
    Inventors: Tomoya Fujimoto, Kenko Okamura, Shigeru Morishita, Masaru Murakami, Akira Adachi, Mitsutoshi Hayashi, Akinari Fujita, Shingo Nagashima, Minoru Kurashina, Kentaro Yoshida
  • Double walled pipe, jacking method and pipe end structure of leading pipe
    Patent number: 6004073
    Abstract: There is provided a double walled pipe having an inner pipe and an outer pipe which is movable relative to the inner pipe in a longitudinal direction of the inner pipe. Acting on only the outer pipe with a pipe jacking power makes it possible to bury the double walled pipe, without damaging the rear end of the inner pipe and also generating an internal stress on the inner pipe. Consequently, it is avoided such a situation that even in use pinholes, cracks, etc. occur on the inner pipe, and thus it is possible to expect an execution with higher reliability.
    Type: Grant
    Filed: November 4, 1996
    Date of Patent: December 21, 1999
    Assignees: Kawasaki Steel Corp., Tokyo Gas Co. Ltd.
    Inventors: Tomoya Fujimoto, Kenko Okamura, Shigeru Morishita, Masaru Murakami, Akira Adachi, Mitsutoshi Hayashi, Akinari Fujita, Shingo Nagashima, Minoru Kurashina, Kentaro Yoshida
  • Double walled pipe, jacking method and pipe end structure of leading pipe
    Patent number: 5615976
    Abstract: There is provided a double walled pipe having an inner pipe and an outer pipe which is movable relative to the inner pipe in a longitudinal direction of the inner pipe. Acting on only the outer pipe with a pipe jacking power makes it possible to bury the double walled pipe, without damaging the rear end of the inner pipe and also generating an internal stress on the inner pipe. Consequently, it is avoided such a situation that even in use pinholes, cracks, etc. occur on the inner pipe, and thus it is possible to expect an execution with higher reliability.
    Type: Grant
    Filed: September 14, 1994
    Date of Patent: April 1, 1997
    Assignees: Kawasaki Steel Corp., Tokyo Gas Co. Ltd.
    Inventors: Tomoya Fujimoto, Kenko Okamura, Shigeru Morishita, Masaru Murakami, Akira Adachi, Mitsutoshi Hayashi, Akinari Fujita, Shingo Nagashima, Minoru Kurashina, Kentaro Yoshida