| 摘要 |
PURPOSE:To enable the supply of pellets of an ordinary particle size, even though the injection amount of a molder is extremely small, by making the inside diameter of the feeding and softening zone of a heating barrel larger than the inside diameter of the other zone and a clearance to the bottom of a plasticizing screw larger than the particle size of the pellets. CONSTITUTION:The inside diameter of the feeding and softening zone A of a heating barrel 1 provided internally with a plasticizing screw 2 is made larger than the inside diameter of the other zone B containing a plasticizing and metering zone and the clearance 4 between the outer wall of the bottom part of the plasticizing screw 2 in the feeding and softening zone A and the inner wall of the heating barrel 1 is made larger than the particle size of a pellet a. Thereby, necessity to make the outside diameter of the plasticizing screw of the feeding and softening zone A considerably smaller than that of the other zone B is eliminated, thereby lowering of a mechanical strength can be prevented. |
