US2821980A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Regulator valve
Assignee: Individual
•
Filing: 1955-04-04
•
Granted: 1958-02-04
•
Expires: 1975-04-04
Abstract
No abstract record available.
Inventors
- 👤 William E Westell
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-04 21:59
CPC Classifications
B; B63; B63C; B63C11/00; B63C11/02; B63C11/18; B63C11/22; B63C11/2209; Y; Y10; Y10S; Y10S137/00; Y10S137/908; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7781; Y10T137/7782; Y10T137/8593; Y10T137/87917; Y10T137/87925
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1540439A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1961-02-03 | 1961-08-05 | 1962-02-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1965-02-03 | 1965-08-05 | 1966-02-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1969-02-03 | 1969-08-05 | 1970-02-04 | $7700.00 | Window Closed / Lapsed |