Tractor having a hydrostatic transmission and method of operating a hydrostatic transmission on a tractor

摘要

A control apparatus is provided for a hydrostatic transmission (101) to simulate a gear drive on a tractor. The hydrostatic transmission (101) has a swashplate that is angularly movable to a plurality of positions, and a proportional valve (106) that provides a control pressure to a servo piston to control the hydrostatic transmission swashplate position. A transmission control lever (120) may be moved to a plurality of positions, each position providing a different voltage signal to a microcontroller (102). The microcontroller (102) receives and converts a voltage signal to a coil current to actuate the proportional valve (106).