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US2634385A Expired / Lapsed US ⏱️ 0.0 years remaining

Electron tube circuits

Assignee: Westinghouse Air Brake Co
•
Filing: 1948-08-24
•
Granted: 1953-04-07
•
Expires: 1968-08-24
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Abstract

No abstract record available.

Inventors

  • 👤 Paul N Martin

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-26 22:47
CPC Classifications
H; H03; H03K; H03K17/00; H03K17/51; H03K17/52

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US1243789A Cited
US1949254A Cited
US2121760A Cited
US2213551A Cited
US2256177A Cited
US2274992A Cited
US2361172A Cited
US2403609A Cited
US2439680A Cited
US2541879A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1956-04-06 1956-10-06 1957-04-07 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1960-04-06 1960-10-06 1961-04-07 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1964-04-06 1964-10-06 1965-04-07 $7700.00 Window Closed / Lapsed

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