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:
Jun. 30, 1987
Filed:
May. 29, 1985
Applicant:
Inventors:
Pierre Karinthi, Jouy-en-Josas, FR;
Maurice Gardent, Herbeys, FR;
Colette Regnier, Echirolles, FR;
Jean Tuccella, Grenoble, FR;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
E02D / ;
U.S. Cl.
CPC ...
405130 ; 405258 ;
Abstract
The injection of liquid nitrogen into the probe (2) is regulated in an on-off manner so as to maintain the temperature of the ground at the coldest point above a value within the range of between -140.degree. C. and -160.degree. C. so as to cause calefaction of the liquid nitrogen. The liquid nitrogen is alternately injected into the central passage (9) and into the annular passage (11) of the probe, these passages being thermally insulated from each other.