Granted Patent
Utility
US 4,644,750 · App. 06/829,148
Heat recovery systems
Inventors:
George E. Lockett, Robert D. Thurston
Patented Case
View Patent ↗
Granted: Feb 24, 1987
Filed: Feb 4, 1986
Inventors
George E. Lockett
Robert D. Thurston
Assignee (at issue)
Energy Soft Computer Systems Limited
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.