Granted Patent
Utility
US 4,433,448 · App. 06/419,119
Power pipe thread cleaner
Inventor:
Martin E. True
Patented Case
View Patent ↗
Granted: Feb 28, 1984
Filed: Sep 16, 1982
Inventor
Martin E. True
Assignee (at issue)
Weatherford/Lamb, 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.