Granted Patent
Utility
US 4,706,180 · App. 06/803,028
Pulse width modulated inverter system for driving single phase a-c induction motor
Inventor:
Frank E. Wills
Patented Case
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Granted: Nov 10, 1987
Filed: Nov 29, 1985
Inventor
Frank E. Wills
Assignee (at issue)
York International Corporation
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.