Granted Patent
Utility
US 5,224,683 · App. 07/848,807
Hydraulic actuator with hydraulic springs
Inventor:
William E. Richeson
Patented Case
View Patent ↗
Granted: Jul 6, 1993
Filed: Mar 10, 1992
Inventor
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.