US2833647A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Tungsten-zirconium-nickel cathodes
Assignee: Superior Tube Co
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Filing: 1957-03-07
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Granted: 1958-05-06
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Expires: 1977-03-07
Abstract
No abstract record available.
Inventors
- 👤 Richard L Hoff
- 👤 Ardrey M Bounds
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 20:45
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/20; H01J1/26
Claims Analysis
Total Claims: 1
Claim 1
Independent Claim
85 words
AN INDIRECTLY-HEATED CATHODE STRUCTURE EACH AS A SLEEVE OR CUP CHARACTERIZED BY HIGH STRENGTH AT CATHODEOPERATING TEMPERATURES, SUSTAINED HIGH LEVEL OF EMISSION AND NEGLIGIBLE SUBLIMATION AND INTERFACE IMPEDANCE AND COMPOSED OF AN ALLOY CONTAINING 0.05% TO 1.5% ZIRCONIUM; 2% TO 4% TUNGSTEN; AT LEAST ONE OF THE ACTIVATING AGENTS ALUMINUM AND MAGNESIUM IN THE RANGE OF NOT MORE THAN 0.07% MAGNESIUM 0.1% ALUMINUM; AND THE BALANCE ESSENTIALLY NICKEL WITH NOT MORE THAN ABOUT 0.02% SILICON, 0.1% IRON, 0.1% MAGANESE, 0.08% CARBON, 0.05% COPPER, AS RESIDUALS.
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) | 1961-05-05 | 1961-11-04 | 1962-05-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-05-05 | 1965-11-04 | 1966-05-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-05-05 | 1969-11-04 | 1970-05-06 | $7700.00 | Window Closed / Lapsed |