Patent US2813807A successfully refreshed from Google Patents.
US2813807A
Expired / Lapsed
US
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Method of making a dispenser cathode
Assignee: US Philips Corp
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Filing: 1954-07-19
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Granted: 1957-11-19
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Expires: 1974-07-19
Abstract
No abstract record available.
Inventors
- 👤 Levi Roberto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 22:03
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/04; H01J9/042; H01J9/047
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
88 words
A METHOD OF MANUFACTURING A THERMIONIC CATHODE ADAPTED TO OPERATE AT ELEVATED TEMPERATURES WHICH COMPRISES FORMING A POROUS BODY OF SINTERED REFRACTORY METAL, IMPREGNATING IN AN INERT ATMOSPHERE THE PORES OF SAID BODY WITH A MOLTEN MIXTURE OF BARIUM OXIDE AND AN OXIDE SELECTED FROM THE GROUP CONSISTING OF ALUMINUM OXIDE, SILICON DIOXIDE, BORIC OXIDE, BERYLLIUM OXIDE, NEODYMIUM OXIDE, LANTHANUM OXIDE AND PRASEODYMIUM OXIDE, A MAJORCOOLING PROPORTION OF THE OXIDES BEING BARIUM OXIDE, AND COOLING SAID IMPREGNATED BODY TO DULL RED HEAT IN LESS THAN ABOUT ONE MINUTE.
Claim 2
Independent Claim
88 words
A METHOD OF MANUFACTURING A THERMIONIC CATHODE ADAPTED TO OPERATE AT ELEVATED TEMPERATURES WHICH COMPRISES FORMING A POROUS BODY OF SINTERED REFRACTORY METAL, IMPREGNATING IN AN INERT ATMOSPHERE THE PORES OF SAID BODY WITH A MOLTEN MIXTURE OF BARIUM OXIDE AND AN OXIDE SELECTED FROM THE GROUP CONSISTING OF ALUMINUM OXIDE, SILICON DIOXIDE, BORIC OXIDE, BERYLLIUM OXIDE, NEODYMIUM OXIDE, LANTHANUM OXIDE AND PRASEODYMIUM OXIDE, A MAJORCOOLING PROPORTION OF THE OXIDES BEING BARIUM OXIDE, AND COOLING SAID IMPREGNATED BODY TO DULL RED HEAT IN LESS THAN ABOUT ONE MINUTE.
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) | 1960-11-18 | 1961-05-20 | 1961-11-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-11-18 | 1965-05-20 | 1965-11-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-11-18 | 1969-05-20 | 1969-11-19 | $7700.00 | Window Closed / Lapsed |