| 摘要 |
PCT No. PCT/EP84/00392 Sec. 371 Date Aug. 2, 1985 Sec. 102(e) Date Aug. 2, 1985 PCT Filed Dec. 7, 1984 PCT Pub. No. WO85/02568 PCT Pub. Date Jun. 20, 1985.In an apparatus for compressing foundry moulding material by pressure gas comprising a pressure vessel for the pressure gas forming an inlet pressure chamber, a moulding chamber positioned below it formed from moulding boxes with sand frames and a pattern plate with pattern on which the moulding material is loosely heaped up prior to compression and a large-area valve arranged between the pressure vessel and the moulding chamber, its closure member frees the valve opening in a few milliseconds, accompanied by the joint action of the pressure in the pressure vessel and thereby moves into the moulding chamber. The closure member is brought into the closed position by a pressure cylinder, whose piston is connected on the stroke side to a high pressure source and with its opposite side forms the movable termination of a gas-pressurized pressure reservoir, the high pressure side outflow being constructed in such a way that the pressure medium flows out at a speed of more than 10 m/s, accompanied by the simultaneous acceleration of the piston under the pressure in the pressure reservoir and the closure member into the open position.
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