Granted Patent
Utility
US 4,425,539 · App. 06/373,554
Control system for AC induction motor
Inventor:
Frank E. Wills
Patented Case
View Patent ↗
Granted: Jan 10, 1984
Filed: Apr 30, 1982
Inventor
Frank E. Wills
Assignee (at issue)
BorgWarner Inc.
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.