Cutting device for crop comminution with automatic shear-bar adjustment

摘要

A shear bar (30) for a crop cutting device (10) has a motor-driven adjusting device for displacing the shear bar (30) relative to the rotable cutting cylinder (22), said adjusting device being equipped with an electronic circuit (116) for detecting the position of the shear bar (30) in relation to the cutting cylinder (22), said circuit (116) automatically bringing the shear bar (30) and the cutting cylinder (22) into the cutting position. When the shear bar (30) is brought into the cutting position together with the cutting cylinder (22) by the motor-driven adjusting device, the flashover of electrical current between the shear bar (30) and the blades (124) of the cutting cylinder (22) is detected. A circuit for voltage comparison detects the flashover of electrical energy and then generates pulses which serve for switching off the motor-driven adjusting device. <IMAGE>