| 摘要 |
PURPOSE:To obtain a mold for injection molding which generates scarcely casting defects with simplified stages by manufacturing a hollow mold and a metallic master from a wooden pattern which is treated to have heat resistance, and manufacturing a front mold and a movable half by using said metallic master. CONSTITUTION:A heat resistant surface treatment is applied on the surface of a wooden pattern 2 of the same shape as the surface shape of a molding by using urethane paint or the like. A hollow mold 8 is made directly by using such pattern 2. Molten cast iron is cast into the mold 8 to make a metallic master 10. This master 10 is turned over, and a stationary fitting mold 5 is manufactured by casting under heating. The master 10 is copied in accordance with the pattern 2 to turn away the metal corresponding to the thickness (t) of the molding, whereby a movable fitting mold is obtained. Both molds 5, 9 are combined, and a molten plastic material is forced into the cavities thereof, whereby an injection molding is obtained. |
