US2634720A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Chimney construction with heat controlling minimizing means
Assignee: Individual
•
Filing: 1947-09-18
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Granted: 1953-04-14
•
Expires: 1967-09-18
Abstract
No abstract record available.
Inventors
- 👤 Robert K Thulman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 15:44
CPC Classifications
F; F23; F23L; F23L17/00; F23L17/02; F23J; F23J13/00; F23J13/02; F23J13/025
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-04-13 | 1956-10-13 | 1957-04-14 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-04-13 | 1960-10-13 | 1961-04-14 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-04-13 | 1964-10-13 | 1965-04-14 | $7700.00 | Window Closed / Lapsed |