| 摘要 |
PURPOSE:To enable easy manufacture of a pattern for a casting mold having an intricate shape in the stage of manufacturing said pattern for casting a member having an intricate three-dimensional curved surface by disposing a core material in a pattern body made of a flexible material and making the core material removable in the stage of forming a sand mold. CONSTITUTION:A pattern 2 for a casting mold provided with an intricate three- dimensional curved surface for casting a pump impeller, etc. is manufactured by constituting the pattern 2 together with a freely removable core material 4 in a pattern body consisting of a flexible material such silicone rubber. A plate material made of a mild steel, lead alloy or plastic is used as the material 4. The material 4 is first removed after molding of a sand mold for casting and the body 3 is removed in succession, in the stage of forming said sand mold by using such pattern 2. Since the body 3 is made of the flexible material, said body shrinks by as much as the volume corresponding to the space made after the removal of the material 4; moreover, it deflects and therefore the pattern is extremely easily removed from the sand mold and the breakage of the sand mold is obviated. |
