Granted Patent
Utility
US 4,715,907 · App. 06/899,323
Method for heat treating ferrous parts
Inventor:
George D. Pfaffmann
Patented Case
View Patent ↗
Granted: Dec 29, 1987
Filed: Aug 22, 1986
Inventor
George D. Pfaffmann
Assignee (at issue)
Tocco, 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.