WORKING APPARATUS FOR FARM FIELD

摘要

PROBLEM TO BE SOLVED: To provide a working height controlling means attachable even to a tractor free from an inputting means for a hydraulic controlling system of a lift mechanism. SOLUTION: This working apparatus is provided with a light-emitting means 5 to emit a light beam at a standard height against the surface of a field, a light- receiving means 6 to get a working height position detection signal of the height of the standard light beam by the light-receiving position of the standard height light beam emitted from the light-emitting means 5, a height position setting means to generate a setting signal of the working height from a position selecting means attached to the tractor and a controlling means to control the working height of the working machine by controlling the hydraulic system of a lift mechanism so as to get a constant deviation of the working height preset by the position selecting means from the standard height detected by the light-receiving means. The controlling means receives a signal relating to a standard plane drawn by the light beam and a signal relating to the selected working height and levels the surface of a field by controlling the working height to draw a moving orbit of the working height of the working machine according to the traveling motion constantly parallel to the standard line drawn by the light beam.