US2438709A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Thermionic tube having secondary electron emissive electrode with surface and form variations
Assignee: Hartford National Bank and Trust Co
•
Filing: 1942-08-06
•
Granted: 1948-03-30
•
Expires: 1962-08-06
Abstract
No abstract record available.
Inventors
- 👤 Labin Edouard
- 👤 Kobilsky Manuel Julio
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 16:23
CPC Classifications
H; H01; H01J; H01J43/00; H01J43/02
Claims Analysis
Total Claims: 0
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1951-03-30 | 1951-09-29 | 1952-03-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1955-03-30 | 1955-09-29 | 1956-03-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1959-03-30 | 1959-09-29 | 1960-03-30 | $7700.00 | Window Closed / Lapsed |