Granted Patent
Utility
US 5,125,371 · App. 07/680,491
Spring driven hydraulic actuator
Inventors:
Fredrick L. Erickson, William E. Richeson
Patented Case
View Patent ↗
Granted: Jun 30, 1992
Filed: Apr 4, 1991
Inventors
Fredrick 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.