US2687747A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Flue conduit with internal heat transfer elements
Assignee: Bock Corp
•
Filing: 1951-05-22
•
Granted: 1954-08-31
•
Expires: 1971-05-22
Abstract
No abstract record available.
Inventors
- 👤 Oscar L Bock
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 15:29
CPC Classifications
F; F24; F24H; F24H1/00; F24H1/18; F24H1/20; F24H1/205
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US164306A
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US1528859A
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US1720244A
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US1947606A
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US1877567A
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US2183561A
Cited
US2565220A
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US2558816A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1957-08-30 | 1958-03-01 | 1958-08-31 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1961-08-30 | 1962-03-01 | 1962-08-31 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1965-08-30 | 1966-03-01 | 1966-08-31 | $7700.00 | Window Closed / Lapsed |