Patent ID: 7665971

Claim:
A method for obtaining power on demand from a diesel engine to operate vehicle functions, the method comprised of: determining, based on a motion of a first control, a function flow rate for each of a plurality of function hydraulic pumps, the plurality of function hydraulic pumps including a front group and a rear group, the front group comprised of a front hoist pump and a front traverse pump and the rear group comprised of a rear hoist pump and a rear traverse pump, and further determining, based on a drive pedal motion, a drive flow rate necessary to operate a vehicle drive pump driven by the engine; adding the function flow rates of the front hoist pump and front traverse pump to determine a front overall flow rate for the front group; adding the function flow rates of the rear hoist pump and rear traverse pump to determine a rear overall flow rate for the rear group; determining a combined flow rate, the combined flow rate being the greater of the front overall flow rate and the rear overall flow rate; determining a function engine speed that is the minimum engine speed necessary to support the combined flow rate; determining a drive pump engine speed necessary to support the drive flow rate; determining a final engine speed by selecting the larger of the function engine speed and the drive pump engine speed; comparing the final engine speed with a current engine speed; and adjusting the current engine speed to the final engine speed.