Granted Patent
Utility
US 6,581,506 · App. 09/647,722
Method and device for controlling supply of working fluid
Inventor:
Yoshiyuki Shimada
Patented Case
View Patent ↗
Granted: Jun 24, 2003
Filed: Dec 7, 2000
Inventor
Yoshiyuki Shimada
Assignee (at issue)
Shin Caterpillar Mitsubishi 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.