Patent US1174897A successfully refreshed from Google Patents.
US1174897A
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Auxiliary air-valve for internal-combustion engines.
Assignee: Individual
•
Filing: 1915-04-20
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Granted: 1916-03-07
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Expires: 1935-04-20
Abstract
No abstract record available.
Inventors
- 👤 Robert N Preston
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 14:50
CPC Classifications
F; F16; F16K; F16K3/00; F16K3/02; F16K3/04; F16K3/06; F16K3/08; Y; Y10; Y10T; Y10T137/00; Y10T137/8593; Y10T137/86493; Y10T137/86718; Y10T137/86743
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) | 1919-03-07 | 1919-09-06 | 1920-03-07 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1923-03-07 | 1923-09-06 | 1924-03-07 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1927-03-07 | 1927-09-06 | 1928-03-07 | $7700.00 | Window Closed / Lapsed |