Granted Patent
Utility
US 4,996,880 · App. 07/327,556
Operating turbine resonant blade monitor
Inventors:
Robert L. Leon, David Hillary Powell
Patented Case
View Patent ↗
Granted: Mar 5, 1991
Filed: Mar 23, 1989
Inventors
Robert L. Leon
David Hillary Powell
Assignee (at issue)
Electric Power Research Institute, 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.