| 摘要 |
1282123 Multi-orifice tubular extrusion die BADISCHE ANILIN- & SODA-FABRIK AG 5 Dec 1969 [6 Dec 1968] 59423/69 Heading B5A The vacuum extraction of volatiles from a thermoplastics melt in an extruder prior to introduction into an injection mould, is facilitated by the increased surface area of the melt extruded from a flow passage 15 into an extraction chamber through a series of concentric flow passages 9 which are defined between an assembly of a centre pin 12, intermediate annular members 2, and an exterior supporting ring 3, which are supported by ball bearings 4 located in oppositely disposed annular grooves 13 of the flow passages 9 and by the attachment of the ring 3, by screws 7, to the flow passage casing 1, which may be surrounded by a heating jacket 8. The ball bearings 4 are introduced into the grooves 13 via at least one tapering opening 14 extending between each groove 13 and the discharge end of the assembly, and which is provided with a removable closure 5. In the described embodiments, each groove 13 is provided with a pair of openings 14, all whereof are located along a diameter and are closed by plugs 5 carried by a cross-member 6, which is secured by screws 10 to the casing 1 and serves to interrupt the tubular discharge from each passage 9. In the Fig. 3 embodiment (not shown), the casing (1) comprises a cross-head to which the centre pin (12) is additionally bolted adjacent the upstream cross entry of the flow passage (15). |
