Granted Patent
Utility
US 4,652,986 · App. 06/826,949
Vital inverter driver
Inventor:
Dick J. Kolkman
Patented Case
View Patent ↗
Granted: Mar 24, 1987
Filed: Apr 7, 1986
Inventor
Dick J. Kolkman
Assignee (at issue)
American Standard 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.