Granted Patent
Utility
US 5,375,422 · App. 08/126,412
High efficiency nitrogen rejection unit
Inventor:
Rayburn C. Butts
Patented Case
View Patent ↗
Granted: Dec 27, 1994
Filed: Sep 27, 1993
Inventor
Rayburn C. Butts
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.