Granted Patent
Utility
US 6,611,440 · App. 10/063,099
Apparatus and method for filtering voltage for an electrostatic precipitator
Inventors:
David F. Johnston, Michael Mahler, Terry Lewis Farmer, Robert Hummell
Patented Case
View Patent ↗
Granted: Aug 26, 2003
Filed: Mar 19, 2002
Inventors
David F. Johnston
Michael Mahler
Terry Lewis Farmer
Robert Hummell
Assignee (at issue)
BHA Group, 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.