Granted Patent
Utility
US 4,381,647 · App. 06/261,108
Load-plus valve for variable displacement pumps
Inventor:
Walter Z. Ruseff
Patented Case
View Patent ↗
Granted: May 3, 1983
Filed: Sep 12, 1980
Inventor
Walter Z. Ruseff
Assignee (at issue)
Caterpillar Tractor Co.
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.