Granted Patent
Utility
US 3,973,918 · App. 05/638,177
Method of making a gas-fired furnace
Inventor:
James T. Tidwell
Patented Case
View Patent ↗
Granted: Aug 10, 1976
Filed: Dec 5, 1975
Inventor
James T. Tidwell
Assignee (at issue)
The Trane Company
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.