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US87728A
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Improvement in valves for blowing-engines
Assignee: —
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Filing: —
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Granted: 1869-03-09
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Expires: 1886-03-09
Abstract
No abstract record available.
Inventors
No inventors recorded.
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-23 17:26
CPC Classifications
F; F16; F16K; F16K15/00; F16K15/02; F16K15/03; F16K15/035; F16K15/036; F16K15/038; F16K15/031; F16K15/14; F16K15/1401; F16K15/148; Y; Y10; Y10T; Y10T137/00; Y10T137/7722; Y10T137/7837; Y10T137/7838; Y10T137/7839; Y10T137/7859; Y10T137/7861; Y10T137/7866; Y10T137/7867; Y10T137/7868; 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) | 1872-03-08 | 1872-09-07 | 1873-03-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1876-03-08 | 1876-09-07 | 1877-03-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1880-03-08 | 1880-09-07 | 1881-03-09 | $7700.00 | Window Closed / Lapsed |