US2921441A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Feed water preheating system for steam power plants
Assignee: Sulzer AG
•
Filing: 1954-12-13
•
Granted: 1960-01-19
•
Expires: 1974-12-13
Abstract
No abstract record available.
Inventors
- 👤 Buri Alfred
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-28 14:40
CPC Classifications
F; F22; F22B; F22B29/00; F22B29/06; F22B29/12; F01; F01K; F01K7/00; F01K7/34; F01K7/40; Y; Y10; Y10S; Y10S122/00; Y10S122/04
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1076335A
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DE441317C
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FR585155A
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DE550827C
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US1925256A
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US2042838A
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US1839121A
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FR714168A
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GB503072A
Cited
US2653447A
Cited
US2747373A
Cited
US2869517A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1963-01-18 | 1963-07-20 | 1964-01-19 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1967-01-18 | 1967-07-20 | 1968-01-19 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1971-01-18 | 1971-07-20 | 1972-01-19 | $7700.00 | Window Closed / Lapsed |