Granted Patent
Utility
US 4,844,412 · App. 07/134,760
Spool detent device for manually operated directional control valve
Inventor:
Shigeru Kubozono
Patented Case
View Patent ↗
Granted: Jul 4, 1989
Filed: Dec 18, 1987
Inventor
Shigeru Kubozono
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.