| 摘要 |
PURPOSE:To mold a bend-free bottomed tube with a uniform section by a method wherein the core pin, the outer surface of which has the same shape as that of the inner surface of the bottomed tube, of a male mold is coaxially inserted in the female mold cavity, the inner surface of which has the same shape as that of the outer surface of the bottomed tube to be molded so as to pour molten molding material through cavity opening part side gates into an annular gap part in order to fill the molding material toward the bottom part of the bottomed tube under the condition that gas and the molten molding material are discharged through a fine hole. CONSTITUTION:In a female mold 1, the inner surface of its cavity 2 is the same shape as the outer surface of a bottomed tube to be molded. The outer surface of a core pin 4 protrusively provided in a male mold has the same shape as that of the inner surface of the bottomed tube to be molded. By closing the female mold 1 and the male mold 3 together, the core pin 4 forms an annular gap 5, which is coaxially inserted in the cavity 2. Two submarine gates 6 are formed at positions, which are centrally symmetrical on the outer surface part on the opening side of the cavity 2, to which a molten molding material basin 8 is formed to be connected through a fine hole 7 at the bottom part outer surface. When molten resin is poured through the submarine gates 6 in the annular gap 5, the molten resin gradually runs to the bottom part of the bottomed tube and air flows through the fine hole 7 at its bottom part into the molten molding material basin 8, resulting in obtaining a bend- free molded article 11 with a uniform section. |
