US2800629A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Earth resistance measuring equipment
Assignee: Evershed and Vignoles Ltd
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Filing: 1956-02-13
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Granted: 1957-07-23
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Expires: 1976-02-13
Abstract
No abstract record available.
Inventors
- 👤 Tagg George Frank
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:25
CPC Classifications
G; G01; G01R; G01R27/00; G01R27/02; G01R27/16; G01R27/18
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
99 words
EARTH RESISTANCE MEASURING EQUIPMENT COMPRISING A PAIR OF CURRENT ELECTRODES FOR INSERTION IN THE EARTH, A FIRST SOURCE FOR SUPPLYING DIRECT CURRENT TO SAID CURRENT ELECTRODES, A PAIR OF POTENTIAL ELECTRODES FOR INSERTION IN THE EARTH BETWEEN SAID CURRENT ELECTRODES, POTENTIOMETER MEANS FOR MEASURING THE POTENTIAL BETWEEN SAID POTENTIAL ELECTRODES, A SECOND SOURCE FOR SUPPLYING DIRECT CURRENT TO SAID POTENTIOMETER MEANS, MEANS FOR INDICATING THE RATIO BETWEEN THE CURRENTS FROM SAID FIRST AND SECOND SOURCES, AND MEANS FOR ADJUSTING SAID RATIO, SAID POTENTIOMETER MEANS BEING CALIBRATED TO READ DIRECTLY IN TERMS OF THE EARTH RESISTANCE BETWEEN SAID POTENTIAL ELECTRODES.
Claim 2
Dependent Claim
99 words
EARTH RESISTANCE MEASURING EQUIPMENT COMPRISING A PAIR OF CURRENT ELECTRODES FOR INSERTION IN THE EARTH, A FIRST SOURCE FOR SUPPLYING DIRECT CURRENT TO SAID CURRENT ELECTRODES, A PAIR OF POTENTIAL ELECTRODES FOR INSERTION IN THE EARTH BETWEEN SAID CURRENT ELECTRODES, POTENTIOMETER MEANS FOR MEASURING THE POTENTIAL BETWEEN SAID POTENTIAL ELECTRODES, A SECOND SOURCE FOR SUPPLYING DIRECT CURRENT TO SAID POTENTIOMETER MEANS, MEANS FOR INDICATING THE RATIO BETWEEN THE CURRENTS FROM SAID FIRST AND SECOND SOURCES, AND MEANS FOR ADJUSTING SAID RATIO, SAID POTENTIOMETER MEANS BEING CALIBRATED TO READ DIRECTLY IN TERMS OF THE EARTH RESISTANCE BETWEEN SAID POTENTIAL ELECTRODES.
References Cited (Backward Citations)
US2648820A
Cited
US2659861A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-07-22 | 1961-01-21 | 1961-07-23 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-07-22 | 1965-01-21 | 1965-07-23 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-07-22 | 1969-01-21 | 1969-07-23 | $7700.00 | Window Closed / Lapsed |