US2640491A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Valve
Assignee: DR PAUL A DEWHIRST
•
Filing: 1950-01-07
•
Granted: 1953-06-02
•
Expires: 1970-01-07
Abstract
No abstract record available.
Inventors
- 👤 Macbain Donald Keith
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 12:01
CPC Classifications
F; F16; F16K; F16K17/00; F16K17/36; F16K17/38; F16K17/386; Y; Y10; Y10T; Y10T137/00; Y10T137/1624; Y10T137/1797; Y10T137/1819
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
US1039693A
Cited
US1081822A
Cited
US1515081A
Cited
US1774395A
Cited
US1981200A
Cited
US2128059A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1956-06-01 | 1956-12-01 | 1957-06-02 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1960-06-01 | 1960-12-01 | 1961-06-02 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1964-06-01 | 1964-12-01 | 1965-06-02 | $7700.00 | Window Closed / Lapsed |