Patent GB-864211-A (GB)
Title: Improvements in apparatus for the production of artificial threads, fibres and like products by the melt-spinning process, and the products thus obtained
IPC: D01D1/06
Filed: 1959-02-25
Abstract: 864,211. Melt-spinning apparatus. ALGEMENE KUNSTZIJDE UNIE N.V. Feb. 25, 1959 [May 5, 1958], No. 6610/59. Class 2(2). In melt-spinning apparatus provided with a gear-type spinning pump, or with two such pumps arranged in series, the driven shaft of each pump is journalled in two close-fitting radial bearings in the pump body, the clearance between the shaft and the bearings communicating with a duct located within the heated portion of the spinning head and leading to a collecting chamber remote from the pump and the spinneret. Any molten spinning material leaking along the shaft from the gear chamber of the pump is thus conducted to the collecting chamber. Leakage of molten material past the driven pump shaft coupling and the pump shaft projecting from the pump exterior is prevented by the close fit of the coupling and the external shaft in their respective bearings. As shown in Fig. 1, granular organic thermoplastic material fed from a hopper 9 into the melting zone 2 is withdrawn in molten condition from the melt reservoir 10 through the duct 12 to the inlet of the gear-pump 13, by which it is pumped through the duct 14 to the inlet of the gear-type spinning pump 15 which forces the melt through the duct 16, chamber 17 and spinneret plate 11 into the blowbox 6. The shafts 19, 20 of the pumps 13, 15 are driven by drive shafts 18, 21 respectively through couplings 22, 23 journalled in bearings 24, 25 mounted in the pumps. Pumps 13, 15 have shafts 26, 27 non-rotatably mounted in the pump housings, on which shafts are rotatably mounted gears which are driven by gear wheels splined to pump shafts 19, 20 which are provided with axial bores 34, 35. Both pumps 13, 15 comprise front plates 28, 29 respectively in which the pump inlets and outlets are located, as well as bores in which are journalled the ends of the shafts 19, 26 and 20, 27 respectively. Both pumps also have back plates 32, 33 bored to receive the opposite ends of the shafts 19, 26 and 20, 27. Polymer leaking along pump shafts 19, 20 escapes into the ducts 36, 40 aligned with the bores 34, 35 of the shafts and flows down ducts 37, 38 into the cavity 39 in the spinning plate holder 5. The ducts are located in the spinning blocks 3, 4 which, together with the block 5 and the pumps, are maintained at a temperature above the melting point of the material to be spun. Leakage polymer drains from the cavity 39 through the outlet 41 into the tray 42 (Figs. 1 and 2) positioned below the outlet 41 and adapted to be slid in and out through the opening 43 in the insulated body 7 between the spinneret holder 5 and the blowbox 6. The tray comprises a shallow portion 44 from which the accumulated solidified leakage polymer may be transferred by means of a rake 46 into the deep portion 45 of the tray, the rake being operated by the handle 51. The apparatus of the invention prevents the accumulation of polymer on the exteriors of the pumps. Specification 823,261 is referred to.