Granted Patent
Utility
US 5,006,021 · App. 07/272,109
High pressure gas drilling
Inventor:
Michael J. Wheetley
Patented Case
View Patent ↗
Granted: Apr 9, 1991
Filed: Nov 16, 1988
Inventor
Michael J. Wheetley
Assignee (at issue)
LTV
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.