| 摘要 |
PURPOSE:To obtain a ferrule having little deviation in an axis without generating a bend on a thin-diameter core pin, by a method wherein a parting line is provided in an edge face of a cylindrical molded object which is made into cavity structure where its axial direction becomes parallel with a mold breaking direction, an end of the thin-diameter core pin is guided by an ejector sleeve and the other end is guided by a stationary side core pin guide hole. CONSTITUTION:Along with starting of mold clamping, the tip edge face of an ejector sleeve 2 hits a stationary side cavity surface. Simultaneously with gradual falling of the ejector sleeve 2 a core pin 3 which has come out of its edge face is inserted into a stationary side core pin guide hole 6. When mold clamping is completed, a molten material is caused to flow into the mold through a gate 7, a spring body 5 which has pressed the ejector sleeve 2 forward is contracted by pressure of the molten material and filling is started. At that time, after the material is filled into the mold in the vicinity of the gate 7, since the material is moved forward in the direction pressing the ejector sleeve 2, bending stress by filling is not applied to the core pin 3 and filling into a cavity 1 is completed. Then a molded object is extruded out of the cavity 1 by a sleeve ejector pin 8. |
