Patent US3234458A successfully refreshed from Google Patents.
US3234458A
Expired / Lapsed
US
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Method for determining resistivity of a metal
Assignee: General Electric Co
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Filing: 1960-11-28
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Granted: 1966-02-08
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Expires: 1980-11-28
Abstract
No abstract record available.
Inventors
- 👤 Charles P Bean
- 👤 Blois Ralph W De
- 👤 Loyd B Nesbitt
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 21:12
CPC Classifications
G; G01; G01N; G01N27/00; G01N27/02; G01N27/023; Y; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/842; Y10S505/843
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
136 words
A METHOD OF MEASURING THE RESISTIVITY OF A METAL AT A LOW TEMPERATURE BELOW 77* K. WHICH COMPRISES MEASURING THE TIME OF DECAY OF THE VOLTAGE INDUCED BY THE CHANGING EDDY-CURRENTS IN A METAL MEMBER SUBJECTED TO AN ABRUPT CHANGE OF MAGNETIC FIELD AT A TEMPERATURE ABOVE 77* K. AT WHICH TEMPERATURE THE RESISTIVITY OF THE METAL IS KNOWN, SUBJECTING SAID METAL MEMBER TO AN ABRUPT CHANGE IN A MAGNETIC FIELD AT A TEMPERATURE BELOW 77* K., MEASURING THE TIME OF DECAY OF THE VOLTAGE INDUCED BY THE CHANGING EDDY-CURRENTS, DETERMINING A RATIO FROM THE TIME VOLTAGE DECAY ABOVE 77* K. OVER THE TIME OF VOLTAGE DECAY BELOW 77* K., AND DETERMINING FROM THE PRODUCT OF THE RATIO AND THE KNOWN HIGHER TEMPERATURE RESISTIVITY VALUE THE RESISTIVITY OF SAID METAL AT ITS TEMPERATURE BELOW 77* K.
Claim 2
Independent Claim
136 words
A METHOD OF MEASURING THE RESISTIVITY OF A METAL AT A LOW TEMPERATURE BELOW 77* K. WHICH COMPRISES MEASURING THE TIME OF DECAY OF THE VOLTAGE INDUCED BY THE CHANGING EDDY-CURRENTS IN A METAL MEMBER SUBJECTED TO AN ABRUPT CHANGE OF MAGNETIC FIELD AT A TEMPERATURE ABOVE 77* K. AT WHICH TEMPERATURE THE RESISTIVITY OF THE METAL IS KNOWN, SUBJECTING SAID METAL MEMBER TO AN ABRUPT CHANGE IN A MAGNETIC FIELD AT A TEMPERATURE BELOW 77* K., MEASURING THE TIME OF DECAY OF THE VOLTAGE INDUCED BY THE CHANGING EDDY-CURRENTS, DETERMINING A RATIO FROM THE TIME VOLTAGE DECAY ABOVE 77* K. OVER THE TIME OF VOLTAGE DECAY BELOW 77* K., AND DETERMINING FROM THE PRODUCT OF THE RATIO AND THE KNOWN HIGHER TEMPERATURE RESISTIVITY VALUE THE RESISTIVITY OF SAID METAL AT ITS TEMPERATURE BELOW 77* K.
References Cited (Backward Citations)
US3090910A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1969-02-07 | 1969-08-09 | 1970-02-08 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1973-02-07 | 1973-08-09 | 1974-02-08 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1977-02-07 | 1977-08-09 | 1978-02-08 | $7700.00 | Window Closed / Lapsed |