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US2649277A Expired / Lapsed US ⏱️ 0.0 years remaining

Check valve

Assignee: DURABLA Manufacturing Co
•
Filing: 1949-11-25
•
Granted: 1953-08-18
•
Expires: 1969-11-25
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Abstract

No abstract record available.

Inventors

  • 👤 Raymond H Blackford

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-01 08:08
CPC Classifications
F; F16; F16K; F16K15/00; F16K15/02; F16K15/025; F16K15/026; F16K15/028; Y; Y10; Y10T; Y10T137/00; Y10T137/7504; Y10T137/7613; Y10T137/7722; Y10T137/7837; Y10T137/7854; Y10T137/7856; Y10T137/7904; Y10T137/7922; Y10T137/7929; Y10T137/7937

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US833559A Cited
US1160707A Cited
US1297930A Cited
US1275697A Cited
GB342774A Cited
US1959644A Cited
DE673045C Cited
US2038267A Cited
US2216622A Cited
US2569176A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1956-08-17 1957-02-16 1957-08-18 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1960-08-17 1961-02-16 1961-08-18 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1964-08-17 1965-02-16 1965-08-18 $7700.00 Window Closed / Lapsed

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