Abstract: A vibrating apparatus for vibrating a flask to compact molding sand in the flask, including an elastically supported vibrating table on which a flask is placed and two unbalanced-weight-type motors mounted on the vibrating table at the sides of the flask for vibrating it by rotating the unbalanced weights of the motors. The axes of rotation of both motors are located on a horizontal line that substantially passes the centroid of the entire elastically supported vibrating apparatus, including the vibrating table, the two motors, the flask, and the molding sand in the flask. Further, both unbalanced weights of the motors are rotated at a speed in one direction.