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:
Nov. 26, 1991
Filed:
Feb. 04, 1991
Gerald T Sweeney, Puyallup, WA (US);
Aardvark Corporation, Puyallup, WA (US);
Abstract
A tubular casing 2 is installed in a tunnel 82 in the earth and the rod 14, 49 is advanced telescopically through the bore of the casing until a portion 49 of the rod is projected into the tunnel ahead of the casing, whereupon a pair of harpoon-like detents 138 anchor that portion of the rod to the wall of the tunnel so that the casing can be retracted in the opposite direction to remove it from around the remainder of the rod. When the distal end of the casing requires a cap 16 because the earth is unstable, pressurized fluid is applied to a piston-like insert 18 in the bore of the casing, to eject the cap and then the insert itself, before the rod is projected into the tunnel. Moreover, when the cap is equipped with a tunneling tool 74 and the casing is used to excavate its own tunnel, the fluid is ejected into the excavation through openings 120 and 80 in the insert and the cap, respectively, to assist the casing in excavating the tunnel; and when the casing is installed, the rod is used as a stopper 136 in the opening 120 of the insert, to plug it while the fluid ejects the insert. Then, the rod is projected into the tunnel ahead of the casing.
Data source: USPTO (United States Patent and Trademark Office) public patent records. Weekly synchronization. How IDiyas builds this profile