US2428079A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air-duct electric heater
Assignee: Individual
•
Filing: 1946-03-04
•
Granted: 1947-09-30
•
Expires: 1966-03-04
Abstract
No abstract record available.
Inventors
- 👤 Sim M Hooper
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 21:08
CPC Classifications
F; F24; F24H; F24H3/00; F24H3/02; F24H3/04; F24H3/0405
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
US427574A
Cited
US1660052A
Cited
US1705812A
Cited
US1829765A
Cited
US1869623A
Cited
US1976367A
Cited
US2156423A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1950-09-29 | 1951-03-31 | 1951-09-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1954-09-29 | 1955-03-31 | 1955-09-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1958-09-29 | 1959-03-31 | 1959-09-30 | $7700.00 | Window Closed / Lapsed |