Granted Patent
Utility
US 4,879,901 · App. 07/185,210
System for evaluating the condition and performance of a valve and valve operator combination
Inventor:
Robert L. Leon
Patented Case
View Patent ↗
Granted: Nov 14, 1989
Filed: Apr 22, 1988
Inventor
Robert L. Leon
Assignee (at issue)
Liberty Technology Center, 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.