| 摘要 |
PURPOSE:To reduce a cost of manufacturing a mold, by forming recesses in a mold body, arranging pipes for introducing cooling medium, embedding the pipes using a low melting metal or the like thereby forming a thermostat, and overlaying it with a reinforcing layer. CONSTITUTION:First, a cavity 10 and a core 11 are cast, and using a cast steel material or the like, a recess (A) is formed on the opposite side of the molding surface. After a cooling pipe 12 is arranged adjacent to the inner surface of the recess (A) and is secured by brazing, low melting point alloy 13 is cast to embed the cooling pipe 12 so that the thermostat 18 is formed. Then sand impregnated with a synthetic resin, cement or the like are poured around the thermostat 18 to form a back-up layer 15 so that the rigidity, etc. of the whole mold are improved to reinforce the mold. Then a nozzle opening and openings for an ejector pin 6 and a return pin 7 are drilled to obtain the intended mold for injection molding. Thus, the cutting-out operation or the like of a steel material can be remarkably reduced. |
