Abstract: A pressure receiving pin includes a fitting portion in a through hole of a fixed mold that communicates with a portion of an exhaust passage on an inlet side, a columnar distal end portion located coaxially with the fitting portion while closer to the exhaust passage that slides with respect to the through hole upon reception of molten metal, and an intermediate portion also located coaxially between the fitting portion and the distal end portion and that has a diameter smaller than a diameter of the distal end portion. An air supply device supplies air when a movable mold is opened such that the air passes through gaps formed between an outer peripheral surface of the intermediate portion and an inner peripheral surface of the through hole and between the distal end portion and the fixed mold, and flows out to the movable mold.