Granted Patent
Utility
US 4,856,549 · App. 07/298,970
Shuttle valve device
Inventor:
Katsumi Ueno
Patented Case
View Patent ↗
Granted: Aug 15, 1989
Filed: Jan 19, 1989
Inventor
Katsumi Ueno
Assignee (at issue)
Diesel Kiki Co., Ltd.
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.