US2623506A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for preheating the feed water for direct fired steam boilers
Assignee: Svenska Maskinverken AB
•
Filing: 1948-01-21
•
Granted: 1952-12-30
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Expires: 1968-01-21
Abstract
No abstract record available.
Inventors
- 👤 Dalin David
- 👤 Hagby Gustav Vilhelm
- 👤 Wykman Torsten Gustaf Albert
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 14:22
CPC Classifications
F; F22; F22D; F22D1/00; F22D1/003; F22B; F22B29/00; F22B29/02
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
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GB190803756A
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US1835610A
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US1852293A
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US1915460A
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DE581883C
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US1975519A
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US2419681A
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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) | 1955-12-30 | 1956-06-30 | 1956-12-30 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1959-12-30 | 1960-06-30 | 1960-12-30 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1963-12-30 | 1964-06-30 | 1964-12-30 | $7700.00 | Window Closed / Lapsed |