METHOD FOR DRAWING PATTERN

PURPOSE:To draw a separating pattern to the side opposite from a molding board quickly and easily by acting the air pressure of compressed air on the bottom surface of the separating pattern after molding by using the pattern provided on the molding board and the separating pattern placed thereon. CONSTITUTION:Sand 6 is rammed and molded by an ordinary molding method. To draw a separating pattern 3, a stop valve 15 is opened to supply compressed air of about several kg/cm pressure, so as to act the air pressure on the bottom surface of the pattern 3 through an air supply port 10. Since the pattern 3 is slightly blown upward by the air pressure, the operator pulls the pattern upward by holding handles 4. The air pressure is used in releasing the tight adhesion between the pattern 3 and the sand mold, therefore, the labor required for the drawing of the patter is just about the force enough to support the own weight of the pattern 3. The pattern 2 on the lower side is drawn to the molding board 1 side by an ordinary method after the drawing of the pattern 3.