Granted Patent
Utility
US 5,859,363 · App. 08/886,659
Device and method for smoke testing of gas furnace heat exchangers
Inventor:
Larry Michael Gouge
Patented Case
View Patent ↗
Granted: Jan 12, 1999
Filed: Jul 1, 1997
Inventor
Larry Michael Gouge
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.