Patent ID: 6675577
Filing Date: 2004-01-13
Classification: B60W,F16H,Y10T

Abstract:
An engine control system for a compact utility tractor having an engine coupled to a hydrostatic transmission, that is coupled to a driven wheel, comprising:a controller; an engine speed sensor, signal-connected to said controller to send an actual engine speed signal to said controller; a speed control actuator having at least a forward and a neutral position, said speed control actuator causing speed command signals from said controller to adjust said hydrostatic transmission speed output to said wheel; said controller having circuitry that continuously monitors engine speed and the position of said control actuator; said controller having circuitry that records said engine speed at the occurrence of said neutral position of said speed control actuator as an unloaded engine speed; and when the engine speed signal decreases under load by a specified amount below said unloaded engine speed, said controller having circuitry that sends a control command to said hydrostatic transmission to reduce tractor speed proportional to the difference between said unloaded engine speed and said actual engine speed signal.