Patent US2887413A successfully refreshed from Google Patents.
US2887413A
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Thermionic cathode for electron tubes and method for producing same
Assignee: Patelhold Patenverwertungs and Elektro-Holding AG
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Filing: 1956-11-19
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Granted: 1959-05-19
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Expires: 1976-11-19
Abstract
No abstract record available.
Inventors
- 👤 Ekkers Gysbert Jacob
- 👤 Patriarca Aldo
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 05:46
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/04; H01J9/042; H01J1/00; H01J1/02; H01J1/13; H01J1/14; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12993; Y10T428/26; Y10T428/263; Y10T428/264; Y10T428/265
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
74 words
A METHOD FOR THE PRODUCTION OF A CATHODE FOR AN ELECTRON TUBE WHICH COMPRISES COATING A SURFACE OF A PIECE OF METAL OF THE GROUPS VB, VIB OR VIIIB OF THE SHORT-PERIODIC SYSTEM WITH AN ALKALINE EARTH METAL OXIDE AND SUCCESSIVELY HEATING RELATIVELY SMALL AREAS OF SAID SURFACE BY MEANS OF AN ELECTRIC ARC TO A TEMPERATURE OF AT LEAST 3500*C. WHEREBY SAID COATING OF ALKALINE EARTH METAL OXIDE IS REMOVED FROM SAID SURFACE.
Claim 2
Independent Claim
74 words
A METHOD FOR THE PRODUCTION OF A CATHODE FOR AN ELECTRON TUBE WHICH COMPRISES COATING A SURFACE OF A PIECE OF METAL OF THE GROUPS VB, VIB OR VIIIB OF THE SHORT-PERIODIC SYSTEM WITH AN ALKALINE EARTH METAL OXIDE AND SUCCESSIVELY HEATING RELATIVELY SMALL AREAS OF SAID SURFACE BY MEANS OF AN ELECTRIC ARC TO A TEMPERATURE OF AT LEAST 3500*C. WHEREBY SAID COATING OF ALKALINE EARTH METAL OXIDE IS REMOVED FROM SAID SURFACE.
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) | 1962-05-18 | 1962-11-17 | 1963-05-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1966-05-18 | 1966-11-17 | 1967-05-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1970-05-18 | 1970-11-17 | 1971-05-19 | $7700.00 | Window Closed / Lapsed |