Granted Patent
Utility
US 4,632,215 · App. 06/602,559
Dual-mode hydraulic vibrator
Inventor:
Richard C. Farris
Patented Case
View Patent ↗
Granted: Dec 30, 1986
Filed: Apr 20, 1984
Inventor
Richard C. Farris
Assignee (at issue)
Litton Resources Systems, 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.