Patent US2564294A successfully refreshed from Google Patents.
Patent US2039587A successfully refreshed from Google Patents.
Patent US2651898A successfully refreshed from Google Patents.
Patent US2860848A successfully refreshed from Google Patents.
Patent US2253307A successfully refreshed from Google Patents.
US2253307A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical circuit
Assignee: AO Smith Corp
•
Filing: 1938-02-18
•
Granted: 1941-08-19
•
Expires: 1958-02-18
Abstract
No abstract record available.
Inventors
- 👤 Richter Walther
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 00:24
CPC Classifications
G; G05; G05F; G05F1/00; G05F1/10; G05F1/12; G05F1/40; G05F1/42
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) | 1944-08-18 | 1945-02-17 | 1945-08-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1948-08-18 | 1949-02-17 | 1949-08-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1952-08-18 | 1953-02-17 | 1953-08-19 | $7700.00 | Window Closed / Lapsed |