Granted Patent
Utility
US 4,290,491 · App. 05/938,613
Rock drill positioning mechanism
Inventor:
James R. Mayer
Patented Case
View Patent ↗
Granted: Sep 22, 1981
Filed: Aug 31, 1978
Inventor
James R. Mayer
Assignee (at issue)
Cooper Industries Holdings
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.