| 摘要 |
PURPOSE:To prepare a ball valve excellent in watertightness, by a method wherein plural places of a ball seat in the peripheral direction thereof are pressed by press protrusions molded to a core mold and a gap is formed between the core mold part other than the protrusions and the ball seat. CONSTITUTION:A spindle is inlaid with the outer mold 2 provided to the side of a moving 6 to set a ball 3 and, after a ball seat 4 is inlaid with and inserted into a core mold 1, the moving mold 6 and a fixed mold 5 are clamped to be closed while the outer mold 2 is closed to press the seat 4 to the ball 3 by ball seat pressing protrusions 11 formed to the mold 1 in the peripheral direction thereof so as to leave intervals therebetween and a space is formed between the core mold part other than protrusions and the seat 4. In the next step, molten resin is introduced into the aforementioned space from an injection port 52 to fill the same and solidified by cooling. |
