| 摘要 |
1,144,046. Extruding composite tubes. INDUPLAS S.p.A. 10 Nov., 1966 [5 Feb., 1966], No. 50498/66. Heading B5A. [Also in Division F2] A plastics tube having a helical core of relatively stronger and more rigid plastics material is made by extruding the core material through a nozzle 15 which is formed in the downstream end 19 of a rotatable bush 9 and extruding the tube wall material through annular extrusion orifices 24, 25 to enclose the core and become bonded thereto. Bush 9 is mounted for rotation between a mandrel 5 and a sleeve 10 and annular orifices 24, 25 are defined by mandrel 5 and the inner surface of end 19, the outer surface thereof and nozzle ring 26, respectively. To enter orifice 24, material from source 4 passes through passageways 23 in end 19. Nozzle ring 26 and a further ring 27 may be adjusted transversely of the material flow by screws 30, 31. Bush 9 may be provided with two or more nozzles 15 fed from different inlets with different and/or differently coloured plastics materials. |
