Granted Patent
Utility
US 5,115,880 · App. 02/749,058
Piezoelectric seismic vibrator with hydraulic amplifier
Inventors:
John J. Sallas, Michael Corrigan
Patented Case
View Patent ↗
Granted: May 26, 1992
Filed: May 8, 1989
Inventors
John J. Sallas
Michael Corrigan
Assignee (at issue)
Halliburton Geophysical Services, 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.