Granted Patent
Utility
US 4,744,505 · App. 06/867,402
Method of making a heat exchanger
Inventor:
Gerald C. Calleson
Patented Case
View Patent ↗
Granted: May 17, 1988
Filed: May 13, 1986
Inventor
Gerald C. Calleson
Assignee (at issue)
The Allen Company, 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.