Foundry sand vibrating screen

The utility model relates to a foundry sand vibrating screen which comprises a bottom plate, a vibrating screen box is installed on the upper surface of the bottom plate, a discharging plate is installed on the outer side, close to the bottom of the vibrating screen box, of the vibrating screen box, a material box is arranged on the upper side of the vibrating screen box, a discharging opening is formed in the bottom of the material box, and L-shaped supporting plates are connected to the two side faces of the material box. And two mounting blocks are mounted on the portions, located on the two sides of the vibrating screen box, of the upper surface of the bottom plate, a reciprocating lead screw is rotationally connected between the two mounting blocks, a sliding block is mounted on the outer surface of the reciprocating lead screw, and the bottom of the L-shaped supporting plate is connected with the sliding block. The two reciprocating lead screws are driven by the driving mechanism to rotate at the same t