Granted Patent
Utility
US 5,217,199 · App. 07/820,145
Connecting valve and hydraulic oil safety and power system in which the connecting valve is used
Inventor:
Heinz Frey
Patented Case
View Patent ↗
Granted: Jun 8, 1993
Filed: Jan 13, 1992
Inventor
Heinz Frey
Assignee (at issue)
Asea Brown Boveri, S.A.
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.