Abstract: The present invention provides a hydraulic motion control or pilot valve and lever assembly for controlling the transmission and steering of a work vehicle such as a crawler tractor, articulated wheel loader or like construction vehicle. The motion control valve and lever assembly is a compact assembly that employs a single lever mounted directly to a valve in order to control the forward and reverse motion of the vehicle, the steering of the vehicle in a left, right or straight direction, and the speed or gear selection of the vehicle. The valve assembly is provided with eight hydraulic signal ports, at least one reservoir port, and at least one pressure supply port. The assembly further has four control spools positioned in respective control spool chambers spaced approximately ninety degrees apart and a fifth control spool positioned in a fifth, central spool chamber.
Type:
Grant
Filed:
May 5, 1997
Date of Patent:
February 9, 1999
Assignee:
Komatsu America International Company
Inventors:
Probir Kumar Chatterjea, Robert Charles Dunn