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:
Aug. 02, 1983
Filed:
Sep. 18, 1981
James M Reichman, Issaquah, WA (US);
Douglas P Kelley, Redmond, WA (US);
Electric Power Research Institute, Inc., Palo Alto, CA (US);
Abstract
An underground boring apparatus including a forwardmost boring head is disclosed herein along with a particular technique for guiding the boring head through the earth along both linear and non-linear paths. In a specific embodiment, the apparatus utilizes an elongated shaft arrangement supporting the boring head at its front end and a tubular housing supporting an intermediate segment of said shaft arrangement for pivotal movement about one of a number of different axes whereby to cause the boring head to pivot relative to the housing. An arrangement of piston/cylinder units is disposed within the housing for pivoting the shaft arrangement in a controlled fashion whereby to determine the direction of movement of the boring head through the earth. This arrangement of piston/cylinder units not only serves to maintain the shaft arrangement and boring head in a pivoted position for causing the latter to move in a curved path, but also serves to maintain the shaft arrangement and boring head in coaxial relationship with the tubular housing for causing the boring head to follow a straight line path.