| 摘要 |
PURPOSE:To enable manufacture of a pattern plate which is of a low cost and can improve the quality of a casting by constituting a pattern plate for a casting mold to be used for static pressure molding of sintered metal having vent holes. CONSTITUTION:A molding flask 6 is placed on a pattern plate 3 fixed with a pattern 5, and molding sand 1 is charged into the flask 6. A sealing cover 7 is mounted to the flask and compressed air is supplied through a feed port 8. The compressed air passes the sand 1 and is discharged to the atmosphere through the cavities 4 of the plate 3 having many cavities 4. When the compressed air passes the molding sand 1, the sand 1 moves together with the air and the sand mold having the high packing density of the sand 1 in proximity to the pattern 5 and the plate 3 is molded. The uniform cavities 4 are continuous over the entire top surface 2 of the plate 3 up to a rear surface 9 and therefore the molded sand mold has no local uneven hardness and has uniform mold hardness. |
