Patent US2472189A successfully refreshed from Google Patents.
US2472189A
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Thermionic tube having a secondary-emission electrode
Assignee: Hartford National Bank and Trust Co
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Filing: 1943-03-22
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Granted: 1949-06-07
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Expires: 1963-03-22
Abstract
No abstract record available.
Inventors
- 👤 Bienfait Henri
- 👤 Veenemans Cornelis Frederik
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 07:12
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/02; H01J9/12; H01J9/125; H01J7/00; H01J7/14; H01J7/18; H01J7/183; H01J9/04; H01J9/042; H01J2201/00; H01J2201/32; Y; Y10; Y10S; Y10S428/00; Y10S428/922; Y10S428/9335; Y10S428/938; Y10T; Y10T428/00; Y10T428/12; Y10T428/12014; Y10T428/12028; Y10T428/12063; Y10T428/12069; Y10T428/12076; Y10T428/12097; Y10T428/12493; Y10T428/12771; Y10T428/12778
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US2146099A
Cited
US2123024A
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US2198329A
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US2190695A
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US2171227A
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US2204252A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-06-06 | 1952-12-06 | 1953-06-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-06-06 | 1956-12-06 | 1957-06-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-06-06 | 1960-12-06 | 1961-06-07 | $7700.00 | Window Closed / Lapsed |