US2157336A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electron discharge apparatus
Assignee: AT&T Inc
•
Filing: 1937-01-06
•
Granted: 1939-05-09
•
Expires: 1957-01-06
Abstract
No abstract record available.
Inventors
- 👤 Raymond A Heising
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 00:24
CPC Classifications
H; H03; H03F; H03F1/00; H03F1/02; H03F1/04; H03F1/06; H03F1/07; H01; H01J; H01J31/00; H01J31/02; H01J31/04; H03B; H03B13/00
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1942-05-08 | 1942-11-07 | 1943-05-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1946-05-08 | 1946-11-07 | 1947-05-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1950-05-08 | 1950-11-07 | 1951-05-09 | $7700.00 | Window Closed / Lapsed |