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:
May. 05, 1981
Filed:
Jun. 25, 1979
Pierre A Moulin, Chaville, FR;
Schlumberger Technology Corp., Houston, TX (US);
Abstract
Downhole cable tension measuring apparatus according to the invention is connected between a cable and well-logging apparatus suspended from the cable in a borehole. A rod is placed between the cable and the well-logging apparatus so as to elongate elastically under the effect of cable tension. A sleeve, fixed at one end of the rod, surrounds the rod. A transformer, the primary of which is wound on the rod, the secondary of which is wound on the sleeve, detects the relative longitudinal displacement of the other end of the rod with respect to the sleeve. Two primary windings displaced on the rod are alternately excited to generate two signals in the secondary coil in order to correct temperature drifts of the circuits. The rod and sleeve are made of the same metal so that each of them will elongate similarly as a function of temperature. The apparatus is placed in a pressure-balanced oil-filled chamber.