Granted Patent
Utility
US 4,623,131 · App. 06/447,133
Molten metal handling vessels
Inventor:
Christopher Roberts
Patented Case
View Patent ↗
Granted: Nov 18, 1986
Filed: Dec 6, 1982
Inventor
Christopher Roberts
Assignee (at issue)
Foseco Trading A.G.
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.