| 摘要 |
PURPOSE:To simultaneously manufacture a plurality of two-layer extrusion materials each made uniform in the shape of at least the second layer material thereof and to make the title apparatus compact by arranging two or more sets of two-layer extrusion blocks in a circular state and forming the pressure equalizing chamber for the second layer material between the second passage and an extruder. CONSTITUTION:The first layer material A is supplied by a gear pump 17 to be extruded through the respective first passages in a plurality of nipples 8 and, at the same time, the second layer material B is supplied from an extruder 2 to be extruded through the second passages 9 between the respective nipples 8 and nozzles 7 to form a two- layer state wherein the second layer material B is coated with the first layer material A. The pressure equalizing chamber 14 for the second layer material B is formed between the extruder 2 and a plurality of the nozzles 7 and the second layer material B is supplied to a plurality of the second passages 9 under uniform pressure through the pressure equalizing chamber 14 and all of the two-layer extrusion materials D extruded from a plurality of two-layer extrusion blocks 11 become uniform products. Since two or more sets of the two-layer extrusion blocks 11 are arranged in a circular state, a large number of two-layer extrusion materials D are simultaneously manufac tured by a compact apparatus. |
