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US2981461A Expired / Lapsed US ⏱️ 0.0 years remaining

Centrifugal fans

Assignee: Westinghouse Electric Corp
•
Filing: 1958-04-18
•
Granted: 1961-04-25
•
Expires: 1978-04-18
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Abstract

No abstract record available.

Inventors

  • 👤 James D Murphy

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-11-05 21:32
CPC Classifications
F; F04; F04D; F04D29/00; F04D29/40; F04D29/42; F04D29/4206; F04D29/4213; F04D27/00; F04D27/009; Y; Y10; Y10S; Y10S415/00; Y10S415/914

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US1689241A Cited
US1797293A Cited
US2004516A Cited
GB455512A Cited
US2160666A Cited
US2316608A Cited
US2327841A Cited
US2393042A Cited
GB672193A Cited
US2690293A Cited
US2798658A Cited
FR1121319A Cited
DE1020761B Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1964-04-24 1964-10-24 1965-04-25 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1968-04-24 1968-10-24 1969-04-25 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1972-04-24 1972-10-24 1973-04-25 $7700.00 Window Closed / Lapsed

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