Granted Patent
Utility
US 5,988,993 · App. 08/849,092
Pressure exchanger having a rotor with automatic axial alignment
Inventor:
Leif J. Hauge
Patented Case
View Patent ↗
Granted: Nov 23, 1999
Filed: May 28, 1997
Inventor
Leif J. Hauge
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.