Granted Patent
Utility
US 4,326,581 · App. 06/107,791
Direct contact, binary fluid geothermal boiler
Inventor:
Pascal M. Rapier
Patented Case
View Patent ↗
Granted: Apr 27, 1982
Filed: Dec 27, 1979
Inventor
Pascal M. Rapier
Assignee (at issue)
United States Department of Energy
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.