| 摘要 |
PURPOSE:To absorb the pulsation of a material and prevent a surging phenomenon thereof in an extrusion molding machine, by providing the extruder with a baffle which can be extended into and retracted from the interior of a barrel and which can be regulated as to the extension length thereof in accordance with the magnitude of a material-driving force. CONSTITUTION:A screw 1 is driven to transfer a plastic material which is introduced from a hopper 15 onto a barrel 2. The plastic material is in a solid state at first and pulsates considerably. The material then turns to be in a molten state via a solid-liquid transient state. When a pulsating molten resin is moved by a screw 1, it impinges upon an inclined surface of an inner peripheral portion of a baffle 3. When the pressure of the material is increased by the pulsation thereof, the baffle 3 is retracted into a baffle insertion recess 14, which is provided between guides 4, 5, against the resilient force of springs 7. Thus, the length of the portion of the baffle 3 which is extended into barrel 2 is varied in accordance with the magnitude of the material-driving force to thereby regulate the flow resistance, absorb the pulsation of the material and prevent a surging phenomenon thereof. |
