The device has storage support (3) that is arranged in frame (1) of machine by joint arrangement. The rotor wheels (8) are rotatably arranged at lower end of mounting plates (9,10). A cover plate (13) is arranged on one side of the rotor wheels, and is mounted on holder (12). The upward facing side of rotor wheels is covered by the cover plate in non parking position of support arm (7). The contact region of the rotor wheels is covered by cover plate in parking position of support arm, so that outer periphery of wheels does not protrude above the contact region of wheels.