| 摘要 |
PURPOSE:To improve the tight adhesion of a film to a pattern and to provide a good sand mold in a V process using the film by disposing vent parts, etc. projecting from the pattern onto the film in tight contact with the pattern, packing sand into the pattern, putting a cover on the sand and evacuating the inside of the pattern. CONSTITUTION:A film 10 is covered on a pattern body 5 and the inside of a vacuum chamber 2 is evacuated 6 to a vacuum to adhere tightly the film 10 to the body 5. A hollow vent hole molding and riser molding, flow-off molding, etc. 9 having airtight surfaces are disposed in the prescribed positions. A moldin flask 11 is put on the pattern and molding sand is packed therein. A shielding film 16 is put on the sand and the inside of a suction pipe 15 and the hollow part 13 of the flask 11 is evacuated 14 to a vacuum to solidify the sand by the atm. pressure. The sand mold is obtd. when the vacuum in the body 5 is released and the mold is parted from the pattern. The parts such as vent parts 9, etc. projecting from the pattern 5 are made separate by which the adhesion of the film 10 is improved and the good vacuum casting mold is obtd. without repair owing to failure. |
