| 摘要 |
PURPOSE: To make a mold, in which a part molded with a sand sucking hole in an upper die is unnecessary to remove, by laying the die having only one set of the sand sucking hole communicated with a mold cavity on a drag and demarcating the mold cavity for molding a shell mold together with the drag. CONSTITUTION: The upper die 11 is laid on the drag 5 and the mold cavity C is demarcated and successively, the discharging hole of a hopper 17 for storing a self-hardening or a gas-hardening molding sand S is communicated with the sand sucking hole 12 in the die 11. Successively, the pressure in the mold cavity C is reduced by working the sucking action on the upper surface of the mold body in the drag 5. By this method, the molding sand S in the hopper 17 is sucked and filled into the mold cavity C. After hardening the filled molding sand S with the lapse of time or by the permeation of hardening gas, the die 11 is risen and separated from the drag 5. Successively, the molding sand S is taken off from the drag 5 and thus, a desired mold can be obtd. |
