Patent US2836491A successfully refreshed from Google Patents.
US2836491A
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Tungsten-titanium-nickel cathodes
Assignee: Superior Tube Co
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Filing: 1957-06-17
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Granted: 1958-05-27
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Expires: 1977-06-17
Abstract
No abstract record available.
Inventors
- 👤 Ardrey M Bounds
- 👤 Richard L Hoff
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 19:43
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/20; H01J1/26
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
79 words
AN INDIRECTLY-HEATED CATHODE STRUCTURE CHARACTERIZED BY HIGH STRENGTH AT CATHODE-OPERATING TEMPERATURES, SUSTAINED HIGH LEVEL OF EMISSION, AND NEGLIGIBLE SUBLIMATION AND COMPOSED OF AN ALLOY CONTAINING 1% TO 5% TUNGSTEN, 0.05% TO 3% TITANIUM, AT LEAST ONE OF THE ACTIVATING AGENTS ALUMINUM, MAGNESIUM AND SILICON IN THE RANGE OF NOT MORE THAN ABOUT 0.07% MAGNESIUM, 0.15% ALUMINUM, 0.05% SILICON, AND THE BALANCE ESSENTIALLY NICKEL WITH NOT MORE THAN ABOUT 0.2% IRON, 0.20% MANGANESE, 0.08% CARBON, AND 0.20% COPPER AS RESIDUALS.
References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-05-26 | 1961-11-25 | 1962-05-27 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-05-26 | 1965-11-25 | 1966-05-27 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-05-26 | 1969-11-25 | 1970-05-27 | $7700.00 | Window Closed / Lapsed |