Granted Patent
Utility
US 4,859,543 · App. 07/043,569
Earth working tool having a working element fabricated from cemented tungsten carbide compositions with enhanced properties
Inventors:
Mark S. Greenfield, Edward V. Conley
Patented Case
View Patent ↗
Granted: Aug 22, 1989
Filed: Apr 28, 1987
Inventors
Mark S. Greenfield
Edward V. Conley
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.