Patent GB-1019052-A (GB)
Title: Apparatus for spinning composite filaments
IPC: D01D5/28
Filed: 1964-03-11
Abstract: 1,019,052. Spinning composite artificial filaments. TEXTILE & CHEMICAL RESEARCH CO. Ltd. March 11, 1964 [March 22, 1963], No. 10347/64. Heading B5B. A spinning head for producing composite or conjugate artificial filaments consisting of two or more different components bonded together along the lengths of the filaments comprises a stack of thin parallel discs each having a central aperture and being spaced apart by annular gaskets so that the assembly forms a series of contiguous thin annular chambers which are fed with two or more spinning solutions or melts. The central apertures of the discs have the same shape but increase progressively in area in the downstream direction, so that the spinning solutions or melts discharged simultaneously from the chambers at these central apertures form a composite stream of spinning solutions or melts consisting of thin concentric cylindrical layers in which contiguous layers differ in composition. The composite stream flows from the last disc in the series through a duct to a spinneret the holes of which are equidistant from one another. In the embodiment illustrated in Fig. 2 (not shown), which is a longitudinal section through one embodiment of a spinneret feeding device according to the invention, the device comprises a stack of thin discs 1<SP>1</SP>, 1<SP>2</SP>, 1<SP>3</SP> to 1<SP>n</SP> spaced apart by annular gaskets 2<SP>1</SP>, 2<SP>2</SP>, 2<SP>3</SP> to 2<SP>n</SP>, so that the assembly forms a succession of contiguous chambers 3<SP>1</SP>, 3<SP>2</SP>, 3<SP>3</SP> to 3<SP>n</SP> each having the shape of a thin circular disc. The discs 1<SP>1</SP> 1<SP>2</SP>, 1<SP>3</SP> to 1<SP>n</SP> have central circular holes 4<SP>1</SP>, 4<SP>2</SP>, 4<SP>3</SP> to 4<SP>n</SP> gradually increasing in diameter from disc 1<SP>1</SP>   to disc 1<SP>n</SP>, the diameter of hole 4<SP>2</SP> being, for example, slightly greater than that of hole 4<SP>1</SP>. The discs each have two series of holes 5, 6 near their edges, the holes in each series being in register with one another. The annular gaskets have two corresponding series of holes 5, 6, so that the holes in the discs and packings form continuous ducts 7, 8, parallel to the axis of the stack of discs. Two different spinning liquids (solutions or melts) A and B are fed at predetermined rates to the ducts 7 and 8, and each flows radially inwards through alternate chambers 3 and upwards through the central holes of the discs to form a composite stream of spinning liquids consisting of coaxial cylindrical layers of liquid A alternating with cylindrical coaxial layers of liquid B. The thickness of the layers is equal to the difference between the lengths of the radii of the central holes in two consecutive discs. The composite stream of spinning liquids having the crosssection shown in the upper part of Fig. 2 is conducted towards the spinneret through the vertical pipe which is coaxial with the stack of discs and attached to the top disc. The diameter of the stream is reduced to correspond with that of the perforated portion of the spinneret by being conducted through the tapered portion of the tube shown at 12 and the narrower portion shown at the top of Fig. 2. The concentric layer structure of the composite liquid stream is preserved in spite of the reduction in diameter of the stream, as shown in cross-section near the top of Fig. 2.