Patent ID: 7544125

Claim:
A method of operation of an agricultural combine comprising the steps of: Providing a body defining a space containing a separating system, and a rear opening spaced rearwardly of the separating system; Providing a propeller disposed in the space between the separating system and the rear opening and operable for propelling a flow of crop residue rearwardly along a crop flow path from the separating system; Providing a cleaning system disposed in the space below the propeller and including a fan disposed for directing a flow of air rearwardly through an air flow channel between the cleaning system and the propeller; Providing an air pressure sensor disposed in the space; Providing a crop residue chopper disposed in connection with the rear opening, and a conveyor mechanism in a rear region of the space in a position for receiving at least a portion of the flow of the crop residue from the propeller and conveying the received flow into the chopper; and Providing a control in connection with the air pressure sensor and a device for determining a speed of the conveyor mechanism; Operating the air pressure sensor for sensing an air pressure condition indicative of plugging of the conveyor mechanism; and Operating the control as a function at least in part of a sensed air pressure and determined speed of the conveyor mechanism in order to adjust the speed of at least one of the fan and the conveyor mechanism responsive thereto.