Granted Patent
Utility
US 4,401,155 · App. 06/234,258
Heat exchanger with extruded flow channels
Inventors:
John Henri Royal, Lawrence S. Graczyk, William J. Owens
Patented Case
View Patent ↗
Granted: Aug 30, 1983
Filed: Feb 13, 1981
Inventors
John Henri Royal
Lawrence S. Graczyk
William J. Owens
Assignee (at issue)
Union Carbide 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.