Patent ID: 7168229
Filing Date: 2007-01-30
Classification: A01D

Abstract:
1. A method of controlling a drop rate of an agricultural header comprising the steps of: providing a self-propelled agricultural implement having a wheel-supported main frame, an engine supported on the main frame, a drive train connected to the engine and providing motive power to the wheels, a crop-engaging header supported on the main frame transversely to the direction of travel of the implement for harvesting crop material from the ground, the header adapted for vertical movement, an operator's cab supported on the main frame and having controls therein for the engine, drive train, header and other components; providing an electronic control unit (ECU) with a memory and programmable signal processing capabilities; providing a visual display device receiving signals from the ECU to dictate the content of the visual output of the display device, the content listing information and alternative choices to the operator in the form of a menu; providing an input device within the operator's cab connected to the ECU for sending signals to the ECU representing input selections of the operator from the menu on the display device, those input signals resulting in output signals from the ECU to the display device and dictating other visual output on the display device; providing an hydraulic header lift and flotation system with hydraulic circuitry having a plurality of valves of various types including a master solenoid valve, a pressure reduction solenoid valve (PRV), a raise solenoid valve, a lower solenoid valve and a float solenoid valve, all connected to the ECU for receiving variable control signals from the ECU to raise and lower the header relative to the ground and manage the header flotation characteristics, the hydraulic circuitry further including header lift cylinders, an accumulator and a reservoir; selecting the drop rate by operator manipulation of the input device in conjunction with observation of visual outputs on the display device, and inputting that selection to the ECU in the form of an output drop rate signal; initiating the lower header cycle with a signal from an operator-activated switch sending a lower header signal to the ECU; via signals from the ECU, pressurizing the header lift and flotation system by energizing the master solenoid valve to 100% and the PRV with current necessary for flotation plus a value for the drop rate corresponding to the output drop rate signal; approximately one-third of a second later, via signals from the ECU, energizing the lower and float solenoid valves to initiate the flow of hydraulic fluid from the header lift cylinders through the lower solenoid valve to the reservoir; approximately two seconds later, via signals from the ECU, modifying the current to the PRV to equal the flotation value only to continue the lowering of the header; approximately 1.5 seconds later, via signals from the ECU, deenergizing the lower solenoid valve to isolate the accumulator and lift cylinders from the PRV; and approximately one-quarter second later, via signals from the ECU, deenergizing the master solenoid valve.