Granted Patent
Utility
US 4,451,162 · App. 06/389,782
Spaced button thrust surface for earth boring bit
Inventor:
William L. Shepherd
Patented Case
View Patent ↗
Granted: May 29, 1984
Filed: Jun 18, 1982
Inventor
William L. Shepherd
Assignee (at issue)
Hughes Tool Company LLC
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.