Granted Patent
Utility
US 5,168,937 · App. 07/769,654
Drill feed control utilizing a variable overcenter valve
Inventor:
Jeffrey W. Hamner
Patented Case
View Patent ↗
Granted: Dec 8, 1992
Filed: Oct 2, 1991
Inventor
Jeffrey W. Hamner
Assignee (at issue)
Ingersoll-Rand Company
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.