Patent US1551868A successfully refreshed from Google Patents.
US1551868A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of the application and construction of electrical heating units
Assignee: Individual
•
Filing: 1919-12-10
•
Granted: 1925-09-01
•
Expires: 1939-12-10
Abstract
No abstract record available.
Inventors
- 👤 Clark Charles Albert
- 👤 Smith Alva Thomas
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:11
CPC Classifications
H; H05; H05B; H05B3/00
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) | 1928-08-31 | 1929-03-02 | 1929-09-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1932-08-31 | 1933-03-02 | 1933-09-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1936-08-31 | 1937-03-02 | 1937-09-01 | $7700.00 | Window Closed / Lapsed |