US1657208A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Vacuum tube
Assignee: Philips North America LLC
•
Filing: 1925-03-23
•
Granted: 1928-01-24
•
Expires: 1945-03-23
Abstract
No abstract record available.
Inventors
- 👤 Greaves Valentine Ford
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-22 23:15
CPC Classifications
H; H01; H01J; H01J9/00; H01J9/24; H01J9/36; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/49117; Y10T29/49124; Y10T29/49147; Y10T29/49151; Y10T29/49153; Y10T29/49826; Y10T29/49908; Y10T29/49925; Y10T29/49927; Y10T29/49929
Claims Analysis
Total Claims: 0
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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) | 1931-01-23 | 1931-07-25 | 1932-01-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1935-01-23 | 1935-07-25 | 1936-01-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1939-01-23 | 1939-07-25 | 1940-01-24 | $7700.00 | Window Closed / Lapsed |