US3121840A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical logging system with means for transmitting different currents over a single pair of conductors
Assignee: Dresser Industries Inc
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Filing: 1959-12-30
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Granted: 1964-02-18
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Expires: 1979-12-30
Abstract
No abstract record available.
Inventors
- 👤 Jefferson P Lamb
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 08:26
CPC Classifications
G; G01; G01V; G01V3/00; G01V3/18; G01V3/20; G01V3/24
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
135 words
IN A SYSTEM FOR OBTAINING MEASUREMENTS CORRELATABLE WITH THE SURFACE LITHOLOGY OF FORMATIONS SURROUNDING A BOREHOLE COMPRISING, IN COMBINATION, A LOGGING TOOL MOVEABLE ALONG THE EXTENT OF A BOREHOLE, A FIRST SOURCE OF ALTERNATING CURRENT LOCATED AT THE TOP OF SAID BOREHOLE, A SECOND SOURCE OF ALTERNATING CURRENT OF A FREQUENCY WHICH IS AN INTEGRAL MULTIPLE OF THE FREQUENCY OF SAID CURRENT FROM SAID FIRST SOURCE, SAID SECOND SOURCE ALSO BEING LOCATED AT THE TOP OF SAID BOREHOLE, A LOGGING CABLE INTERCONNECTED BETWEEN SAID TOOL AND SAID SOURCES AND CONTAINING AT LEAST A SINGLE PAIR OF CONDUCTORS, MEANS FOR COMBINING SAID CURRENTS FROM SAID FIRST AND SECOND SOURCES FOR TRANSMISSION TO SAID LOGGING TOOL OVER SAID SINGLE PAIR OF CONDUCTORS, MEANS INCLUDING SAID SOURCES AND NORMAL AND LATERAL CURRENT ESTABLISHING ELECTRODES FOR ESTABLISHING NORMAL AND
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) | 1967-02-17 | 1967-08-19 | 1968-02-18 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1971-02-17 | 1971-08-19 | 1972-02-18 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1975-02-17 | 1975-08-19 | 1976-02-18 | $7700.00 | Window Closed / Lapsed |