Granted Patent
Utility
US 4,583,207 · App. 06/444,988
Magnetohydrodynamic geophone
Inventor:
Sedley J. Greer, Jr.
Patented Case
View Patent ↗
Granted: Apr 15, 1986
Filed: Nov 29, 1982
Inventor
Sedley J. Greer, Jr.
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.