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:
Sep. 12, 1989
Filed:
May. 11, 1988
Armond D Cosman, Austin, TX (US);
Joe T Minarovic, Georgetown, TX (US);
Minnesota Mining and Manufacturing Company, St. Paul, MN (US);
Abstract
A method and system for determining the location of a first insulated conductor and a plurality of similar branch conductors that are branches of the first conductor, but without ohmic contact being made with the first conductors. A passive marker having a resonant circuit that includes an inductor and capacitor is provided for each of the branch conductors and is positioned to be inductively coupled to the first conductor and the associated branch conductor. The first conductor is a part of a closed loop circuit and each branch conductor is a part of separate closed loop circuits. An alternating signal applied to any one of the closed loop circuits is inductively transmitted to each of the other closed loops that is inductively coupled to a passive marker having a resonant frequency equal to the frequency of the alternating signal. Flow of alternating signals in the closed loops and passive markers cause a detectable electromagnetic signal to be produced to identify the location of the first conductor, branch conductors and passive markers when conducting the alternating signals.