US3425447A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Gas-duct valve with flexible closure
Assignee: United States Steel Corp
•
Filing: 1965-12-10
•
Granted: 1969-02-04
•
Expires: 1985-12-10
Abstract
No abstract record available.
Inventors
- 👤 Marshall J Mccullough
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 03:06
CPC Classifications
F; F24; F24F; F24F13/00; F24F13/08; F24F13/10; B; B22; B22D; B22D18/00; B22D18/06; F16; F16K; F16K7/00; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86509; Y10T137/86718
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US70511A
Cited
US1606278A
Cited
US2483401A
Cited
US2890716A
Cited
US3000395A
Cited
US3092130A
Cited
US3292657A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1972-02-04 | 1972-08-05 | 1973-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1976-02-04 | 1976-08-05 | 1977-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1980-02-04 | 1980-08-05 | 1981-02-04 | $7700.00 | Window Closed / Lapsed |