| 摘要 |
1474869 Mixing apparatus EGAN MACHINERY CO 24 Dec 1975 [10 Feb 1975] 52873/75 Heading B1C [Also in Divisions B4 and B5] A particulate additive is mixed with a molten resin being delivered by a plasticiser screw 16, by delivering the particles into the molten resin in a zone D of the screw which is at a lower pressure e.g. at atmospheric, than a zone upstream thereof, the delivery being effected by a screw 24 of a feeder 20 whose bore opens directly into that of the plasticiser 10. The plasticiser may comprise an extruder, or an injection moulding machine when the plasticiser screw 16 is also reciprocatory. The resin is melted and raised in pressure during delivery through feed, A, transition, B. and metering sections, C, of the screw, with the low pressure in zone D being effected by a channel depth which is greater than in the metering section C. The resin is delivered from the low pressure zone D through transition, E, metering, F, and preferably a mixing section G. A vent, e.g. to which vacuum is applied, may be located upstream of the location at which the additive is delivered, or may be located at 19 in a further low pressure section, H, which is followed by a further transition, I, and a metering section, J. Melting of the resin is effected by heaters 18, and friction developed by the screw 16, and the feeder may be provided with heaters 26 to maintain the temperature of the plasticiser barrel at its junction with the feeder. The feeder 20 may be provided with ports 27 for the introduction of a gas, to exclude oxygen, or as a catalyst for the additive or resin. The feeder and plasticiser screw drives are adjustable independently, and preferably also simultaneously. The resin may be thermoplastic or thermosetting. The examples relate to nylon resin, and glass fibre or resin additive, and to polyester resin and calcium metasilicate or glass fibre additive. |
