Granted Patent
Utility
US 5,609,088 · App. 08/506,792
Hydraulic control system for excavations with an improved flow control valve
Inventor:
Hee-Woo Park
Patented Case
View Patent ↗
Granted: Mar 11, 1997
Filed: Jul 25, 1995
Inventor
Hee-Woo Park
Assignee (at issue)
Daewoo Heavy Industries 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.