US2739283A
Expired / Lapsed
US
⏱️ 0.0 years remaining
High-vacuum device
Assignee: National Research Corp
•
Filing: 1952-02-23
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Granted: 1956-03-20
•
Expires: 1972-02-23
Abstract
No abstract record available.
Inventors
- 👤 Jonathan R Roehrig
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 06:00
CPC Classifications
H; H01; H01J; H01J41/00; H01J41/02; H01J41/08
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2097760A
Cited
US2497213A
Cited
US2497823A
Cited
US2595611A
Cited
US2570124A
Cited
US2625586A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1959-03-20 | 1959-09-19 | 1960-03-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1963-03-20 | 1963-09-19 | 1964-03-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1967-03-20 | 1967-09-19 | 1968-03-20 | $7700.00 | Window Closed / Lapsed |