Granted Patent
Utility
US 4,612,650 · App. 06/719,965
DC arc furnace
Inventor:
Sven-Einar Stenkvist
Patented Case
View Patent ↗
Granted: Sep 16, 1986
Filed: Apr 4, 1985
Inventor
Sven-Einar Stenkvist
Assignee (at issue)
Asea AB
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.