Granted Patent
Utility
US 4,451,047 · App. 06/429,533
Seal
Inventors:
David P. Herd, Duane E. Gibson
Patented Case
View Patent ↗
Granted: May 29, 1984
Filed: Sep 30, 1982
Inventors
David P. Herd
Duane E. Gibson
Assignee (at issue)
SMITH INTERNATIONAL, 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.