Patent US2402087A successfully refreshed from Google Patents.
Patent US2512495A successfully refreshed from Google Patents.
Patent US2491781A successfully refreshed from Google Patents.
US2491781A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Cold cathode tube voltage indicator
Assignee: EDI HOLDING Inc
•
Filing: 1945-10-25
•
Granted: 1949-12-20
•
Expires: 1965-10-25
Abstract
No abstract record available.
Inventors
- 👤 Spierer Theodore
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-27 18:36
CPC Classifications
G; G01; G01F; G01F23/00; G01F23/30; G01F23/32; G01F23/36
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US505243A
Cited
US612518A
Cited
US2161744A
Cited
US1424637A
Cited
US1406312A
Cited
US1753330A
Cited
US1867216A
Cited
US2013012A
Cited
US2141236A
Cited
US2269760A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1952-12-19 | 1953-06-20 | 1953-12-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1956-12-19 | 1957-06-20 | 1957-12-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1960-12-19 | 1961-06-20 | 1961-12-20 | $7700.00 | Window Closed / Lapsed |