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US2544871A Expired / Lapsed US ⏱️ 0.0 years remaining

Three-phase transformer

Assignee: McGraw Electric Co
•
Filing: 1947-04-24
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Granted: 1951-03-13
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Expires: 1967-04-24
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Abstract

No abstract record available.

Inventors

  • 👤 David E Wiegand

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-31 18:57
CPC Classifications
H; H01; H01F; H01F27/00; H01F27/24; H01F27/25; H01F41/00; H01F41/02; H01F41/0206; H01F41/0213; Y; Y10; Y10T; Y10T29/00; Y10T29/49; Y10T29/49002; Y10T29/4902; Y10T29/49071; Y10T29/49075; Y10T29/49078

Claims Analysis

Total Claims: 0
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References Cited (Backward Citations)

US523572A Cited
US1390050A Cited
US1766654A Cited
US1780110A Cited
US2220732A Cited
US2408212A Cited
US2401952A Cited
US2355169A Cited
US2458112A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1954-03-12 1954-09-11 1955-03-13 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1958-03-12 1958-09-11 1959-03-13 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1962-03-12 1962-09-11 1963-03-13 $7700.00 Window Closed / Lapsed

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