Granted Patent
Utility
US 4,421,135 · App. 06/231,404
Hydraulic selector valve having joy stick control
Inventors:
Ronald W. Harshman, Lynn A. Dietrich
Patented Case
View Patent ↗
Granted: Dec 20, 1983
Filed: Feb 4, 1981
Inventors
Ronald W. Harshman
Lynn A. Dietrich
Assignee (at issue)
Walter Kidde & Co., Inc.
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.