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US2813222A
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Travelling wave tube
Assignee: US Philips Corp
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Filing: 1952-04-03
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Granted: 1957-11-12
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Expires: 1972-04-03
Abstract
No abstract record available.
Inventors
- 👤 Diemer Gesinus
- 👤 Knol Kornelis Swier
- 👤 Jonker Johan Lodewijk Hendrik
- 👤 Versnel Arie
- 👤 Groendijk Hendrik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 08:04
CPC Classifications
H; H01; H01J; H01J25/00; H01J25/34; H01J25/36; H01J25/38
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2300052A
Cited
US2367332A
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US2602148A
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US2580007A
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US2632130A
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US2681951A
Cited
US2595698A
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US2608668A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1960-11-11 | 1961-05-13 | 1961-11-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1964-11-11 | 1965-05-13 | 1965-11-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1968-11-11 | 1969-05-13 | 1969-11-12 | $7700.00 | Window Closed / Lapsed |