Granted Patent
Utility
US 4,538,338 · App. 06/490,729
Method for manufacturing a furnace heat exchanger and plate assembly
Inventors:
Russell W. Hoeffken, John Wiese
Patented Case
View Patent ↗
Granted: Sep 3, 1985
Filed: May 2, 1983
Inventors
Russell W. Hoeffken
John Wiese
Assignee (at issue)
Snyder General 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.