Granted Patent
Utility
US 4,693,421 · App. 06/851,349
Apparatus for conducting hot gases from an exhaust pipe
Inventor:
Allan Cameron
Patented Case
View Patent ↗
Granted: Sep 15, 1987
Filed: Apr 14, 1986
Inventor
Allan Cameron
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.