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. 14, 1976
Filed:
Jul. 30, 1974
Applicant:
Inventor:
Paul A Crafton, Potomac, MD (US);
Assignee:
Other;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E01G / ;
U.S. Cl.
CPC ...
61 42 ; 61 84 ; 61106 ; 299-1 ;
Abstract
A drilling or tunneling system in which a first, relatively large diameter bore is made, the loosened material is mixed with a stabilizing material, and a plurality of smaller permanent ducts are formed behind the boring unit. Power, control information, stabilizing material and excess material are conveyed to and from the unit by means of a series of mobile carrier units which travel through the smaller ducts and which function in the manner of an endless conveyor.