Patent US3490693A successfully refreshed from Google Patents.
US3490693A
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US
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Gaseous fuel control for circulating heating systems
Assignee: Vaillant GmbH
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Filing: 1967-12-01
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Granted: 1970-01-20
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Expires: 1987-12-01
Abstract
No abstract record available.
Inventors
- 👤 Hans Meier
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 17:05
CPC Classifications
F; F24; F24H; F24H9/00; F24H9/20; F24H9/2007; F24H9/2035; F23; F23N; F23N1/00; F23N1/08; F23N1/085; F23N1/087; F24D; F24D19/00; F24D19/10; F24D19/1006; F23N2235/00; F23N2235/12; F23N2235/14; F23N2235/18; F23N2235/20; Y; Y10; Y10S; Y10S148/00; Y10S148/051
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) | 1973-01-19 | 1973-07-21 | 1974-01-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1977-01-19 | 1977-07-21 | 1978-01-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1981-01-19 | 1981-07-21 | 1982-01-20 | $7700.00 | Window Closed / Lapsed |