Patent US3374430A successfully refreshed from Google Patents.
US3374430A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical resistance standard having an output voltage representative of applied frequency, and of resistivity and permeability of a conducting medium
Assignee: Emerson Process Management Ltd
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Filing: 1965-01-14
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Granted: 1968-03-19
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Expires: 1985-01-14
Abstract
No abstract record available.
Inventors
- 👤 Tenny D Lode
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 17:01
CPC Classifications
G; G01; G01R; G01R1/00; G01R1/20; G01R1/203
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
152 words
THE METHOD OF ESTABLISHING A VOLTAGE REPRESENTATIVE OF A STANDARD VALUE OF FREQUENCY AND REPRESENTATIVE OF THE RESISTIVITY AND PERMEABILITY OF A CONDUCTING BODY COMPRISING THE STEPS OF: MAKING FOUR SPACED ELECTRICAL CONNECTIONS, EACH CONNECTION BEING MADE DIRECTLY TO A SURFACE OF A CONDUCTING BODY HAVING A KNOWN VALUE OF THE PRODUCT OF RESISTIVITY AND PERMEABILITY AND EACH CONNECTION BEING MADE TO THE SURFACE AT A LOCATION SPACED FROM THE OTHER CONNECTIONS IN A KNOWN SURFACE SPACING RELATION; APPLYING AN ALTERNATING CURRENT THROUGH TWO OF SAID SPACED CONNECTIONS, SAID ALTERNATING CURRENT HAVING A PRECISELY KNOWN FREQUENCY OF SUFFICIENTLY HIGH RATE SUCH THAT THE ELECTROMAGNETIC SKIN DEPTH IN SAID CONDUCTING BODY IS SMALL COMPARED TO THE SPACING BETWEEN ANY TWO OF SAID CONNECTIONS; AND CONNECTING THE OTHER TWO SPACED ELECTRICAL CONNECTIONS TO VOLTAGE MEASUREMENT MEANS; WHEREBY SAID VOLTAGE IS SUBSTANTIALLY PROPORTIONAL TO THE SQUARE ROOT OF THE PRODUCT OF SENSITIVITY, PERMEABILITY, AND FREQUENCY.
Claim 2
Independent Claim
152 words
THE METHOD OF ESTABLISHING A VOLTAGE REPRESENTATIVE OF A STANDARD VALUE OF FREQUENCY AND REPRESENTATIVE OF THE RESISTIVITY AND PERMEABILITY OF A CONDUCTING BODY COMPRISING THE STEPS OF: MAKING FOUR SPACED ELECTRICAL CONNECTIONS, EACH CONNECTION BEING MADE DIRECTLY TO A SURFACE OF A CONDUCTING BODY HAVING A KNOWN VALUE OF THE PRODUCT OF RESISTIVITY AND PERMEABILITY AND EACH CONNECTION BEING MADE TO THE SURFACE AT A LOCATION SPACED FROM THE OTHER CONNECTIONS IN A KNOWN SURFACE SPACING RELATION; APPLYING AN ALTERNATING CURRENT THROUGH TWO OF SAID SPACED CONNECTIONS, SAID ALTERNATING CURRENT HAVING A PRECISELY KNOWN FREQUENCY OF SUFFICIENTLY HIGH RATE SUCH THAT THE ELECTROMAGNETIC SKIN DEPTH IN SAID CONDUCTING BODY IS SMALL COMPARED TO THE SPACING BETWEEN ANY TWO OF SAID CONNECTIONS; AND CONNECTING THE OTHER TWO SPACED ELECTRICAL CONNECTIONS TO VOLTAGE MEASUREMENT MEANS; WHEREBY SAID VOLTAGE IS SUBSTANTIALLY PROPORTIONAL TO THE SQUARE ROOT OF THE PRODUCT OF SENSITIVITY, PERMEABILITY, AND FREQUENCY.
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) | 1971-03-19 | 1971-09-18 | 1972-03-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1975-03-19 | 1975-09-18 | 1976-03-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1979-03-19 | 1979-09-18 | 1980-03-19 | $7700.00 | Window Closed / Lapsed |