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.

Date of Patent:
Jun. 13, 1989

Filed:

Mar. 07, 1988
Applicant:
Inventor:

Gerald R Oldham, Rotherdam, GB;

Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
E21C / ; E21C / ;
U.S. Cl.
CPC ...
299 73 ; 173 42 ; 299 15 ; 299 75 ;
Abstract

Apparatus for excavating a tunnel of generally quadrilateral cross-section, the apparatus comprising a cutting head having the head being mounted for rotation about a first axis and a second axis to change the angle of inclination of the cutter. The cutter may be retracted on its support and may be moved transversely of the excavation on a slide, horizontally. It may be moved vertically by mounting the head on an arm pivotally mounted or in another embodiment by mounting the head on a vertically movable carrier carried on a slide. This can be used for excavating by making a set of cuts at various angles; first and second slots are generally parallel at the face but the first slots are inclined to the second, and to the face, so that they intersect. A third set of slots may intersect the first and second sets (for example, vertically) to separate the material from the face in convenient-sized blocks.


Find Patent Forward Citations

Loading…