Granted Patent
Utility
US 4,162,156 · App. 05/792,553
Process for melting cast iron borings
Inventor:
Dewein H. Naffziger
Patented Case
View Patent ↗
Granted: Jul 24, 1979
Filed: May 2, 1977
Inventor
Dewein H. Naffziger
Assignees (at issue)
Advance Achievement Systems, Inc.
Wisconsin Centrifugal, 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.