Abstract: The present invention comprises a control system for automatically controlling the height of a header on a combine. The combine header includes a cutter bar which is adapted to float upwardly and downwardly in response to variations in the terrain. A linkage interconnects the cutter bar with a movable cam and a microswitch so that the microswitch is actuated in response to upward and downward movement of the cutter bar. The microswitch is connected to solenoids within a hydraulic valve and the hydraulic valve is connected in the hydraulic system with the hydraulic cylinder for raising and lowering the header. When the cutter bar lifts upwardly the microswitches are moved to a condition wherein they cause the valve to actuate the hydraulic cylinder for lifting the header. Similarly when the cutter bar moves downwardly the hydraulic cylinder is actuated to lower the header. When the cutter bar is in a neutral position, the hydraulic cylinder remains motionless.

Abstract: The apparatus of the present invention comprises a torque amplifier assembly having a first shaft and a second shaft, each with complementary direct drive gears and complementary torque amplifier gears thereon. The torque amplifier and direct drive gears are rotatable on the first shaft, but may be independently coupled to the first shaft by means of a torque amplifier clutch or a direct drive clutch. In order to stop the rotation of the torque amplifier and direct drive gears, the clutches for both the direct drive gear and the torque amplifier gear are simultaneoulsy actuated to cause them both to be engaged to the first shaft. The resulting difference in gear ratios causes the two shafts to stop rotating.