Patent US1513870A successfully refreshed from Google Patents.
US1513870A
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US
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Method and device to use multiplied pressures for automatic altitude adjustments for aircraft
Assignee: Individual
•
Filing: 1923-07-25
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Granted: 1924-11-04
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Expires: 1943-07-25
Abstract
No abstract record available.
Inventors
- 👤 Stanwood W Sparrow
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-05 22:34
CPC Classifications
F; F02; F02D; F02D9/00; F02D2700/00; F02D2700/02; F02D2700/0217; F02D2700/0225; F02D2700/0228; F02D2700/023; F02D2700/0235; Y; Y10; Y10S; Y10S60/00; Y10S60/904
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) | 1927-11-04 | 1928-05-05 | 1928-11-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1931-11-04 | 1932-05-05 | 1932-11-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1935-11-04 | 1936-05-05 | 1936-11-04 | $7700.00 | Window Closed / Lapsed |