Granted Patent
Utility
US 5,338,158 · App. 07/854,678
Pressure exchanger having axially inclined rotor ducts
Inventor:
Leif J. Hauge
Patented Case
View Patent ↗
Granted: Aug 16, 1994
Filed: Jun 29, 1992
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.