| 摘要 |
PURPOSE:To provide an injection molding machine which enables a double-layer molding simultaneously with one mold cavity by arranging a resin injection nozzle in a double construction, inner and outer, while the inner nozzle is movable forward and backward and a valve is provided to stop the injection from the inner nozzle. CONSTITUTION:The tip of an inner nozzle 13 is made movable forward and backward with respect to an outer nozzle while a valve rod 14 is provided to stop injection closing a nozzle hole 10 of the inner nozzle 13. An outer nozzle 10 is pressed on a nozzle hole running through a cavity 22 of an outer die 4 while the inner nozzle 13 advances to a part of the cavity 22, a condition under which a resin is injected both from between 13c the outer nozzle 10 and the inner nozzle 13 and an internal hole 13b of the inner nozzle 13. When the resin almost fills the cavity 22, the inner hole 13b is closed with the valve rod 14 while the inner nozzle 13 is retracted so that the tip thereof flushes the outer nozzle 10. Then, external resin alone is injected to complete the molding. |
