Granted Patent
Utility
US 4,335,748 · App. 06/139,751
Bidirectional control valve
Inventors:
Ronald A. Olansen, Linda Pavelski
Patented Case
View Patent ↗
Granted: Jun 22, 1982
Filed: Apr 14, 1980
Inventors
Ronald A. Olansen
Linda Pavelski
Assignee (at issue)
Posi-Seal International, 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.