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Patent US2525565A successfully refreshed from Google Patents.
US2525565A
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Filamentary cathode for electron tubes
Assignee: Varian Medical Systems Inc
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Filing: 1948-07-12
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Granted: 1950-10-10
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Expires: 1968-07-12
Abstract
No abstract record available.
Inventors
- 👤 Harold E Sorg
- 👤 Paul D Williams
- 👤 Donald F Drieschman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 16:21
CPC Classifications
H; H01; H01J; H01J1/00; H01J1/02; H01J1/13; H01J1/15; Y; Y10; Y10T; Y10T428/00; Y10T428/12; Y10T428/12333; Y10T428/12493; Y10T428/12535; Y10T428/12576; Y10T428/12771; Y10T428/12806; Y10T428/12826; Y10T428/12833; Y10T428/1284
Claims Analysis
Total Claims: 2
Claim 1
Independent Claim
29 words
A FLAMENTARY CATHODE FOR AN ELECTRON TUBE COMPRISING A WIRE CORE OF TUNGSTEN-TANTALUM ALLOY, AND AN EMITTER LAYER COMPRISING CONVOLUTIONS OF CARBURIZED THORIATED KTUNGSTEN WIRE ON SAID WIRE CORE.
Claim 2
Dependent Claim
29 words
A FLAMENTARY CATHODE FOR AN ELECTRON TUBE COMPRISING A WIRE CORE OF TUNGSTEN-TANTALUM ALLOY, AND AN EMITTER LAYER COMPRISING CONVOLUTIONS OF CARBURIZED THORIATED KTUNGSTEN WIRE ON SAID WIRE CORE.
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) | 1953-10-09 | 1954-04-10 | 1954-10-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1957-10-09 | 1958-04-10 | 1958-10-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1961-10-09 | 1962-04-10 | 1962-10-10 | $7700.00 | Window Closed / Lapsed |