Granted Patent
Utility
US 4,353,726 · App. 06/255,006
Method and apparatus for preheating pulverous materials prior to their introduction into a melting furnace
Inventor:
Robert R. Rough, Sr.
Patented Case
View Patent ↗
Granted: Oct 12, 1982
Filed: Apr 17, 1981
Inventor
Robert R. Rough, Sr.
Assignee (at issue)
Owens-Illinois Inc.
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.