CONTROL DEVICE FOR A HYDRAULIC MOTOR

摘要

A control device for controlling a speed of a hydraulic motor includes a housing defining a first void. A speed valve is disposed within the first void and is moveable between a first speed valve position and a second speed valve position. The first void includes a speed valve pressure chamber disposed at one end of the speed valve. A speed valve spring is disposed at another end of the speed valve. The housing further defines a speed change port and a speed change passage interconnecting the speed change port and the speed change pressure chamber for directing a pressurized fluid directly into the speed valve pressure chamber to exert a pressure force on the speed valve and bias against the speed valve spring to move the speed valve between the first speed valve position and the second speed valve position.