Granted Patent
Utility
US 4,638,846 · App. 06/164,867
Method of making thin-walled ductile iron castings
Inventors:
Allen D. Ackerman, Conrad G. Perkey, Robert A. Martin, William M. Justusson
Patented Case
View Patent ↗
Granted: Jan 27, 1987
Filed: Jul 1, 1980
Inventors
Allen D. Ackerman
Conrad G. Perkey
Robert A. Martin
William M. Justusson
Assignee (at issue)
Ford Motor Company
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.