Granted Patent
Utility
US 5,113,941 · App. 07/610,356
Surface sand detection monitoring device and method
Inventor:
Joseph F. Donovan
Patented Case
View Patent ↗
Granted: May 19, 1992
Filed: Nov 7, 1990
Inventor
Joseph F. Donovan
Assignee (at issue)
Baker Hughes Holdings LLC
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.