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:
Dec. 23, 1980
Filed:
Dec. 15, 1978
Applicant:
Inventors:
Terence Hubbard, Little Eaton, GB;
Eric A Jackson, Swanwick, GB;
Assignee:
Perard Engineering Limited, Ripley, GB;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E21C / ; E21C / ;
U.S. Cl.
CPC ...
299 31 ; 105161 ; 299 43 ; 299 64 ;
Abstract
A track-mounted vehicle having legs which can be retracted or extended, so that the vehicle can be raised to permit advancement of the track and then lowered, the vehicle either being raisable off the track to permit advancement, or having captivating means by which the track is raised, together with the vehicle, the track and the vehicle having rack-and-pinion or rack-and-chain drive means so that, in the raised position, the track can be advanced by said drive means and, in the lowered position, the vehicle is movable along the track by said drive means.