Granted Patent
Utility
US 4,333,364 · App. 06/138,079
Method for manufacturing a rotary drill bit having a solid forged, unitary body
Inventor:
Daniel W. Varel
Patented Case
View Patent ↗
Granted: Jun 8, 1982
Filed: Apr 7, 1980
Inventor
Daniel W. Varel
Assignee (at issue)
Varel Manufacturing Company
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.