A corn head attachment has a sweeper device extending across a working width of the corn head attachment. The sweeper device is attached to the attachment frame by support arms pivotable about a first pivot. The sweeper device position relative to the frame is adjustable by a longitudinal adjusting device parallel to the travel direction and height-adjustable about the first pivots. The adjusting device moves the sweeper device along a curved path in a first direction away from a first position, in which a rotary axle of the sweeper device is at a leading area of a harvesting slot, into a second position above a rearward area of the harvesting slot and also moves the sweeper device in opposite direction. The adjustment of the sweeper device along the curved path is controlled by a forced guiding action to avoid collision of the sweeper device with other corn head attachment components.
