| 摘要 |
PURPOSE:To prevent gas leakage and make a gas mold easily by sucking and passing gaseous amine through org. binder contg. molding sand filled in a molding flask on a pattern plate and sucking the gaseous amine with a deodorizing device after curing. CONSTITUTION:A molding flask 7 is placed on the top surface of a pattern plate 1, and molding sand 9 contg. an org. binder is filled in the space between both approximately up to the topsurface of the flask 7. Next, a cover member 10 is put on the top surface of the flask 7, and further a film sheet 13 is put on the top surface thereof while a vent hole 14 is held communicated with a gas supply hole 12. A cap 17 which is communicated and connected 16 at one end to a gas generator 15 is placed on the top surface of the member 10 in communication with the hole 12 and the hole 14. Next, a vacuum pump is operated to suck and supply the gaseous amine in the generator 15 into the flask 7 and to suck and remove the same through the sand 9 then through the vent hole 3, an evacuated chamber 2 and a suction pipe 20 into a deodorizing device. Thereafter, the cap 17 is removed and the vacuum pump is kept run to remove the gaseous amine remaining in the sand 9, after which the mold is released and this completes the molding operation. |
