Granted Patent
Utility
US 4,709,753 · App. 06/904,406
Uni-directional fin-and-tube heat exchanger
Inventor:
Allan J. Reifel
Patented Case
View Patent ↗
Granted: Dec 1, 1987
Filed: Sep 8, 1986
Inventor
Allan J. Reifel
Assignee (at issue)
Nordyne LLC
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.