Granted Patent
Utility
US 4,825,973 · App. 07/087,003
Full flow solenoid valve for air gun operation
Inventor:
Earnest R. Harrison
Patented Case
View Patent ↗
Granted: May 2, 1989
Filed: Aug 18, 1987
Inventor
Earnest R. Harrison
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.