| 摘要 |
1,062,020. Plasticizing moulding materials BORG-WARNER CORPORATION. Aug. 25, 1964 [Sept. 5, 1963], No. 34788/64. Heading B5A. A preheating device for a plasticizing machine comprises a hopper 32 for supplying plastic material to a heating chamber 27 through trap means 31 which alternatively connects the heating chamber 27 to a source of heating fluid, With the trap 31 in the position seen in Fig. 3 (not shown) heated air is forced through a pipe (47), a chamber (46) and a screen (49) into the chamber 27 where it heats a charge of plastic material. The air is exhausted through a passage 21 in a ram 19 slidable in a cylinder 16. The entrance to the ram passage 21 is covered by a screen 23. When the material is sufficiently heated the ram 19 is moved rearwardly to allow the material to drop into the cylinder 16. Forward movement of the ram forces the material into a cylinder 13 containing a plasticizing screw 11 which delivers the plasticized material to an injection or extrusion moulding machine. Movement of the trap 31 to the left in Fig. 3 (by means of a cylinder 34) allows a fresh charge of material from the hopper 32 to drop through a passage (51) into the chamber 27. |
