Granted Patent
Utility
US 4,386,668 · App. 06/188,443
Sealed lubricated and air cooled rock bit bearing
Inventor:
Verble W. Parish
Patented Case
View Patent ↗
Granted: Jun 7, 1983
Filed: Sep 19, 1980
Inventor
Verble W. Parish
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.