| 摘要 |
1,149,780. Multi-screw extruders. SUMITOMO ELECTRIC INDUSTRIES Ltd. 28 Dec., 1966 [11 Jan., 1966], No. 57914/66. Heading B5A. [Also in Division B1] In a screw extruder, a first screw 1 fed with plastics material from a hopper 3 delivers plasticized material to a second screw 2 which has a smaller diameter, but higher speed of rotation than the first. Screws 1, 2 are driven by motors 6, 7 respectively, which motors may be controlled for speed of rotation from a common unit 8. The drive for both screws may derive from a single motor. Material entering zone 11 is de-aerated by vacuum means connected to outlet 5. The barrel of screw 1 may be heated, as also may that of screw 2 initially, although owing to the relatively high rotational speed of screw 2 cooling means are also provided to prevent heat degradation. The screw housings may be thermally insulated from one another. A specific plastics material mentioned is polyvinyl chloride. |
