Granted Patent
Utility
US 6,418,745 · App. 09/813,504
Heat powered heat pump system and method of making same
Inventor:
Frank W. Ratliff
Patented Case
View Patent ↗
Granted: Jul 16, 2002
Filed: Mar 21, 2001
Inventor
Frank W. Ratliff
Assignee (at issue)
Mechanical Solutions Inc.
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.