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:
Apr. 14, 1992
Filed:
Nov. 19, 1990
Applicant:
Inventors:
Assignee:
Atlas Copco Constructing and Mining Technique AB, Stockholm, SE;
Attorneys:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21D / ;
U.S. Cl.
CPC ...
405142 ; 405141 ; 405138 ;
Abstract
Tunnel boring machine for reaming of a pilot tunnel (11). The machine housing (12) is provided with a projecting part in front of the boring head (13), said projecting part comprising a part (20) being fixed relative to the machine housing and a shield (19) being separable from the fixed part. This arrangement permits substantially uninterrupted excavation of the tunnel and prevents the excavated soil from becoming wedged between the boring head and the tunnel front.