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US2556181A
Expired / Lapsed
US
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High-frequency electron discharge device
Assignee: Unisys Corp
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Filing: 1946-12-28
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Granted: 1951-06-12
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Expires: 1966-12-28
Abstract
No abstract record available.
Inventors
- 👤 William W Hansen
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 22:44
CPC Classifications
H; H01; H01J; H01J25/00; H01J25/50; H01J25/52; H01J25/58; H01J25/587
Claims Analysis
Total Claims: 0
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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) | 1954-06-11 | 1954-12-11 | 1955-06-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1958-06-11 | 1958-12-11 | 1959-06-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1962-06-11 | 1962-12-11 | 1963-06-12 | $7700.00 | Window Closed / Lapsed |