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:
Sep. 19, 1989
Filed:
May. 20, 1988
Applicant:
Inventors:
Glen O Baker, Kent, WA (US);
Dmitry Feldman, Seattle, WA (US);
Shiu S Ng, Seattle, WA (US);
Albert W Chau, Redmond, WA (US);
John E Mercer, Kent, WA (US);
Assignee:
FlowMole Corporation, Kent, WA (US);
Primary Examiner:
Int. Cl.
CPC ...
E21B / ; E21B / ; E21B / ; E21B / ;
U.S. Cl.
CPC ...
175 61 ; 175 62 ; 175122 ; 175203 ; 175296 ; 175398 ; 175415 ;
Abstract
There is disclosed herein an apparatus for providing an underground tunnel utilizing a steerable pneumatically powered, elongated percussive downhole hammer having a forwardmost cutting bit which is asymmetrically configured with respect to the elongation axis of the hammer. This hammer is steered through the ground, that is, made to move along a straight path or a particular curved path, by controlling the way in which it is pneumatically powered and/or the way in which it is urged forward and/or the way in which its cutting bit is rotated.