Granted Patent
Utility
US 6,176,897 · App. 09/000,844
High frequency pressure swing adsorption
Inventor:
Bowie G. Keefer
Patented Case
View Patent ↗
Granted: Jan 23, 2001
Filed: Dec 30, 1997
Inventor
Bowie G. Keefer
Assignee (at issue)
Questor Industries 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.