Patent US1867478A successfully refreshed from Google Patents.
US1867478A
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Nonreturn valve for breathing appliances
Assignee: Firm Dragerwerk Heinr & Bernh
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Filing: 1928-06-07
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Granted: 1932-07-12
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Expires: 1948-06-07
Abstract
No abstract record available.
Inventors
- 👤 Stelzner Hermann
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 20:36
CPC Classifications
A; A61; A61M; A61M16/00; A61M16/20; A61M16/208; F; F16; F16K; F16K15/00; F16K15/14; F16K15/1402; F16K15/148; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7838; Y10T137/7839; Y10T137/784; Y10T137/7879; Y10T137/7888; Y10T137/789
Claims Analysis
Total Claims: 0
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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) | 1935-07-12 | 1936-01-11 | 1936-07-12 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1939-07-12 | 1940-01-11 | 1940-07-12 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1943-07-12 | 1944-01-11 | 1944-07-12 | $7700.00 | Window Closed / Lapsed |