| 摘要 |
PROBLEM TO BE SOLVED: To provide a degassing device for a mold, which prevents the fine powder of molten metal or the mist of a lubricant and a mold releasing agent from intruding into a clearance between a valve rod and a valve cylinder or guide cylinder, has a very simple structure, is easy to manufacture and can restrain air leakage. SOLUTION: The degassing device for a mold is equipped with a valve body 2 which is mounted on the acral part of the valve rod 3 and opens or closes the opening 11 of the valve cylinder 1, and a guide cylinder 4 which is placed inside the valve cylinder 1 and retains the valve rod 3 so as to slide. The degassing device is designed to close the opening 11 of the valve cylinder 1 as the valve body 2 is pushed up by the molten metal which ascends through a degassing passage from a mold cavity when the gas in the mold cavity is sucked by means of a vacuum unit. A concave groove 7 having a width matching with the advancing or receding distance of the valve rod 3 is surroundedly formed on the inner circumferential face of the guide cylinder 4, and the valve rod 3 is fitted with a sealing member 8 at a position corresponding to the concave groove 7 so that the concave groove 7 is sealed airtightly as the sealing member 8 of the valve rod 3 touches the side wall face 71 of the concave groove 7 when the opening 11 of the valve cylinder 1 is open. COPYRIGHT: (C)2008,JPO&INPIT
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