US2687127A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Insulated flue
Assignee: Individual
•
Filing: 1951-06-18
•
Granted: 1954-08-24
•
Expires: 1971-06-18
Abstract
No abstract record available.
Inventors
- 👤 John J Leffler
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:39
CPC Classifications
F; F23; F23J; F23J13/00; F23J13/02; F23J13/025; F23J11/00
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-08-23 | 1958-02-22 | 1958-08-24 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-08-23 | 1962-02-22 | 1962-08-24 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-08-23 | 1966-02-22 | 1966-08-24 | $7700.00 | Window Closed / Lapsed |