Granted Patent
Utility
US 6,017,487 · App. 08/158,853
Lid of preformed refractory material for metallurgical melting furnace
Inventor:
George L. Fish
Patented Case
View Patent ↗
Granted: Jan 25, 2000
Filed: Nov 29, 1993
Inventor
George L. Fish
Assignee (at issue)
Aluminum Company of America
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.