Granted Patent
Utility
US 4,917,196 · App. 07/394,045
Excavating tooth for an earth auger
Inventors:
Stephen P. Stiffler, Wayne H. Beach, Don C. Rowlett, Steven D. Shirk
Patented Case
View Patent ↗
Granted: Apr 17, 1990
Filed: Aug 15, 1989
Inventors
Stephen P. Stiffler
Wayne H. Beach
Don C. Rowlett
Steven D. Shirk
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.