US2723375A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Induction logging apparatus
Assignee: Schlumberger Well Surveying Corp
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Filing: 1953-03-02
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Granted: 1955-11-08
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Expires: 1973-03-02
Abstract
No abstract record available.
Inventors
- 👤 Nick A Schuster
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 01:24
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/26; G01V3/28
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
160 words
IN APPARATUS FOR INVESTIGATING AN ELECTRICAL PROPERTY OF EARTH FORMATIONS, THE COMBINATION OF ALTERNATING CURRENT ENERGIZED TRANSMITTER COIL MEANS AND RECEIVER COIL MEANS, MEANS MOUNTING SAID TRANSMITTER COIL MEANS AND SAID RECEIVER COIL MEANS FOR MOVEMENT IN PROXIMITY TO SAID FORMATIONS AND MAINTAINING SAID RECEIVER COIL MEANS IN FIXED RELATION TO SAID TRANSMITTER COIL MEANS FOR INDUCTIVE COUPLING THEREWITH SUCH THAT THE PHASE RELATION BETWEEN THE ENERGIZING CURRENT IN SAID TRANSMITTER COIL MEANS AND ANY VOLTAGE INDUCED IN SAID RECEIVER COIL MEANS WILL VARY AS A FUNCTION OF THE ELECTRICAL CONDUCTIVITY OF THE ADJACENT EARTH FORMATIONS, MEANS INCLUDING SAID TRANSMITTER COIL MEANS AND SAID RECEIVER COIL MEANS FOR PRODUCING THE ALTERNATING CURRENT SIGNAL ENERGIZING SAID TRANSMITTER COIL MEANS AND FOR CAUSING THE FREQUENCY OF SAID ALTERNATING CURRENT SIGNAL TO VARY AS A FUNCTION OF VARIATIONS IN SAID PHASE RELATION, AND MEANS FOR OBTAINING INDICATIONS OF THE FREQUENCY OF SAID SIGNAL AS A MEASURE OF THE ELECTRICAL CONDUCTIVITY OF THE FORMATIONS.
Claim 2
Dependent Claim
160 words
IN APPARATUS FOR INVESTIGATING AN ELECTRICAL PROPERTY OF EARTH FORMATIONS, THE COMBINATION OF ALTERNATING CURRENT ENERGIZED TRANSMITTER COIL MEANS AND RECEIVER COIL MEANS, MEANS MOUNTING SAID TRANSMITTER COIL MEANS AND SAID RECEIVER COIL MEANS FOR MOVEMENT IN PROXIMITY TO SAID FORMATIONS AND MAINTAINING SAID RECEIVER COIL MEANS IN FIXED RELATION TO SAID TRANSMITTER COIL MEANS FOR INDUCTIVE COUPLING THEREWITH SUCH THAT THE PHASE RELATION BETWEEN THE ENERGIZING CURRENT IN SAID TRANSMITTER COIL MEANS AND ANY VOLTAGE INDUCED IN SAID RECEIVER COIL MEANS WILL VARY AS A FUNCTION OF THE ELECTRICAL CONDUCTIVITY OF THE ADJACENT EARTH FORMATIONS, MEANS INCLUDING SAID TRANSMITTER COIL MEANS AND SAID RECEIVER COIL MEANS FOR PRODUCING THE ALTERNATING CURRENT SIGNAL ENERGIZING SAID TRANSMITTER COIL MEANS AND FOR CAUSING THE FREQUENCY OF SAID ALTERNATING CURRENT SIGNAL TO VARY AS A FUNCTION OF VARIATIONS IN SAID PHASE RELATION, AND MEANS FOR OBTAINING INDICATIONS OF THE FREQUENCY OF SAID SIGNAL AS A MEASURE OF THE ELECTRICAL CONDUCTIVITY OF THE FORMATIONS.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1958-11-07 | 1959-05-09 | 1959-11-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1962-11-07 | 1963-05-09 | 1963-11-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1966-11-07 | 1967-05-09 | 1967-11-08 | $7700.00 | Window Closed / Lapsed |