Granted Patent
Utility
US 4,989,670 · App. 07/352,810
Heat exchanger
Inventor:
Peter N. Foley
Patented Case
View Patent ↗
Granted: Feb 5, 1991
Filed: May 17, 1989
Inventor
Peter N. Foley
Assignee (at issue)
York International Corporation
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.