Granted Patent
Utility
US 4,574,839 · App. 06/601,780
Directional control valve with integral flow control valve
Inventors:
Rudolph E. Yeh, Joseph L. Zagotta
Patented Case
View Patent ↗
Granted: Mar 11, 1986
Filed: Apr 19, 1984
Inventors
Rudolph E. Yeh
Joseph L. Zagotta
Assignee (at issue)
J. I. Case Company
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.