Granted Patent
Utility
US 5,221,072 · App. 07/820,470
Resilient hydraulic actuator
Inventors:
Frederick L. Erickson, William E. Richeson
Patented Case
View Patent ↗
Granted: Jun 22, 1993
Filed: Jan 14, 1992
Inventors
Frederick L. Erickson
William E. Richeson
Assignee (at issue)
North American Philips Corporation
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.