US2223137A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Differential operated check valve
Assignee: Individual
•
Filing: 1939-06-19
•
Granted: 1940-11-26
•
Expires: 1959-06-19
Abstract
No abstract record available.
Inventors
- 👤 Tyden Emil
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 22:40
CPC Classifications
F; F16; F16K; F16K15/00; F16K15/02; F16K15/06; F16K15/063; F16K15/18; F16K15/184; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7781; Y10T137/7783
Claims Analysis
Total Claims: 0
No claims parsed yet. Click Sync Now above to re-index claims from Google Patents.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1943-11-26 | 1944-05-27 | 1944-11-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1947-11-26 | 1948-05-27 | 1948-11-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1951-11-26 | 1952-05-27 | 1952-11-26 | $7700.00 | Window Closed / Lapsed |