| 摘要 |
PURPOSE:To maintain the dimensional accuracy of a core formed with notches in a core print part and to eliminate the generation of flash as well as to improve productivity by imposing the above-mentioned core on a lower mold, mating an upper mold with the core print part deformed by the heat of the metallic mold and dividing the core to the plural cores from the notches thereby decreasing the rate of deformation. CONSTITUTION:The core 14 supported to the core print part 18 having the notches 12 is imposed on the lower mold 15 based on a projection 19 thereof. The mold 15 is kept heated during a casting operation stage and the core print part 18 is deformed and warped by the heat thereof. The upper mold 16 together with a horizontal core 17 is then mated with the mold 15 and when the molds are closed, the core print part 19 is pressed by the top surface of the space part 21 of the core 17 and therefore, the deformed parts are corrected and bending stresses are concentrated to the notches 12. Cracks are, therefore, generated in the notches 12 and the core print part 18 is broken from the notches 12. The thermal deformation is thus decreased in the individual core print parts 18 and since the clearance S' in the space part 21 for housing the core print parts 18 is small, the flashing of the product is prevented.
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