Granted Patent
Utility
US 4,825,907 · App. 07/209,662
Low restriction fluid control valve
Inventors:
J. Les Johnson, John R. Hanning
Patented Case
View Patent ↗
Granted: May 2, 1989
Filed: Jun 21, 1988
Inventors
J. Les Johnson
John R. Hanning
Assignee (at issue)
Parker-Hannifin 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.