Granted Patent
Utility
US 4,267,502 · App. 06/041,965
Precipitator voltage control system
Inventors:
Robert O. Reese, Karl Wieber, James T. Hartman
Patented Case
View Patent ↗
Granted: May 12, 1981
Filed: May 23, 1979
Inventors
Robert O. Reese
Karl Wieber
James T. Hartman
Assignee (at issue)
Envirotech, 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.