Granted Patent
Utility
US 6,190,033 · App. 09/288,929
High gas dispersion efficiency glass coated impeller
Inventors:
Wayne N. Rickman, Philip E. McGrath, Matthias Heinzmann
Patented Case
View Patent ↗
Granted: Feb 20, 2001
Filed: Apr 9, 1999
Inventors
Wayne N. Rickman
Philip E. McGrath
Matthias Heinzmann
Assignee (at issue)
Pfaulder, 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.