Granted Patent
Utility
US 4,886,710 · App. 07/039,208
Mining/construction tool bit having bit body fabricated from Mn-B steel alloy composition
Inventor:
Mark S. Greenfield
Patented Case
View Patent ↗
Granted: Dec 12, 1989
Filed: Apr 16, 1987
Inventor
Mark S. Greenfield
Assignee (at issue)
KENNAMETAL 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.