Vorrichtung zum Schmelzspinnen

摘要

In melt-spinning apparatus of the type in which the molten material is supplied by a screw-type extruder to a positive displacement metering pump of the rotary gear type, the driving shaft of the metering pump is driven by the screw of the screw type extruder or pump, the drive being taken from the end of the screw at the discharge end of the screw pump and the coupling or other drive from the screw to the metering pump being enclosed in a casing or housing, the free space in which communicates with the free spaces in the screw pump and metering pump casings respectively and the joints between the drive casing and the screw pump and metering pump casings respectively being liquid-tight. As shown in Fig. 1, grains of polymer 2 in the supply vessel 1 are melted by the spiral tube melting grid 5 to which a heating fluid is supplied through the inlet end 6 and thereafter flows through the heating jacket 9 surrounding the melt receiver 8 and the heating jacket 20 surrounding the casing 13 of a screw pump 12. The melt flows through channels 10, 11 to the screw pump 12 in which the melt is moved towards the discharge port 25 by the screw 14 integral with the shaft 15 carrying the gear-wheel 16. The melt is pumped under pressure through the discharge port 25 and inlet 26 to the metering pump 27 which supplies the melt through duct 34 and filter 35 to the monofil spinneret 38. The discharge end of the screw 14 is integral with a journal 24 provided at its free end with a groove 31 and rotatably mounted in the bore 23 in the closure 21 attached to casing 13 by bolts 22. The tongue 30 at the free end of the shaft 29 of the gear pump 27 fits into the groove 31. The pump 27 is attached to the closure 21 by bolts 28. Melt leaking out of the pump 27 is immediately picked up by the fresh melt at the discharge end of the screw pump and is at once returned to the gear pump together with fresh melt. Decomposition and carbonizing of melt due to long residence in the pump assembly are thereby prevented and the gear pump does not require a packing gland. In the other illustrated embodiment of the invention the melt is delivered by the screw pump to three metering gear pumps in parallel via a liquid-tight housing containing a gear-wheel coupled to the discharge end of the screw pump screw and mounted on the drive shaft of one of the gear pumps and also gear-wheels mounted on the shafts of the other two gear-pumps. The first gear-wheel drives the other gear-wheels either directly or through intermediate gearwheels, all the gear-wheels being in the same plane.