Patent ID: 7721813

Claim:
A draft load control system for positioning a ground-engaging implement coupled to a vehicle providing a primary source of motive power, said vehicle comprising: a ground-supported frame having forward and rearward portions; an engine supported on said frame for propelling said vehicle, said coupled implement, and operative components thereof; a vehicle control communication system; an operator input apparatus, said operator input apparatus accepting a desired draft load value and providing a corresponding desired draft load signal to said vehicle control communication system; a hydraulic position actuator having a height control cylinder disposed to raise and lower said implement with respect to the ground in response to an implement position control signal; a hydraulic pressure sensor connected to said hydraulic position actuator and configured for detecting the fluid pressure within the height control cylinder and for providing a pressure output signal representative of the fluid pressure; and an electronic draft load controller connected to said vehicle control communications system configured to receive said pressure output signal and said desired draft load signal from said vehicle control communication system, the controller programmed to derive from the pressure output signal an actual draft load on the vehicle using a proportional relationship between vertical forces on the implement and the draft load, wherein changes in the cylinder fluid pressure reflect variations in the vertical forces and accordingly the draft load, the controller configured to then calculate from the current draft load an implement position control signal and send said implement position control signal to said hydraulic position actuator; the controller further configured to manage said implement position based on said position control signal whereby a substantially constant draft load is maintained on said tractor.