US1830826A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Refractory diaphragm for use in surface-combustion apparatus
Assignee: Individual
•
Filing: 1925-08-17
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Granted: 1931-11-10
•
Expires: 1945-08-17
Abstract
No abstract record available.
Inventors
- 👤 Cox Frederick John
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 17:10
CPC Classifications
F; F23; F23D; F23D14/00; F23D14/12; F23D14/16; F23D2203/00; F23D2203/10; F23D2203/106; Y; Y10; Y10S; Y10S264/00; Y10S264/57
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) | 1934-11-09 | 1935-05-11 | 1935-11-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1938-11-09 | 1939-05-11 | 1939-11-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1942-11-09 | 1943-05-11 | 1943-11-10 | $7700.00 | Window Closed / Lapsed |