The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Dec. 21, 1999
Filed:
Nov. 04, 1996
Tomoya Fujimoto, Chiyoda-ku, JP;
Kenko Okamura, Chiyoda-ku, JP;
Shigeru Morishita, Chiyoda-ku, JP;
Masaru Murakami, Chiba, JP;
Akira Adachi, Chiba, JP;
Mitsutoshi Hayashi, Yokohama, JP;
Akinari Fujita, Yokohama, JP;
Shingo Nagashima, Yokohama, JP;
Minoru Kurashina, Yokohama, JP;
Kentaro Yoshida, Yokohama, JP;
Kawasaki Steel Corp., Kobe, JP;
Tokyo Gas Co. Ltd., Tokyo, JP;
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.