Granted Patent
Utility
US 5,038,871 · App. 07/538,634
Apparatus for supporting a direct drive drilling unit in a position offset from the centerline of a well
Inventor:
Michael C. Dinsdale
Patented Case
View Patent ↗
Granted: Aug 13, 1991
Filed: Jun 13, 1990
Inventor
Michael C. Dinsdale
Assignee (at issue)
National Oilwell, 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.