Patent GB-780620-A (GB)
Title: Process and apparatus for the continuous treatment of artificial filaments
IPC: D01F11/02
Filed: 1955-04-18
Abstract: <PICT:0780620/IV (a)/1> <PICT:0780620/IV (a)/2> Artificial filaments are continuously treated by feeding the filaments to the lower end of a rotating roller, the axis of which is at an angle to the horizontal and at an angle to the axis of a fixed and non-rotating assembly of rods, the assembly comprising a plurality of rods mounted to define the edges of a prism and disposed below the roller, withdrawing the filaments from the upper end of the roller after they have passed round the roller and the assembly of rods in a number of axially advancing helical turns, directing a liquid for treating the filaments on to the upper end of the roller, and collecting the treating liquid from the lower end of the roller.  The liquid may be water for washing filaments of regenerated cellulose produced by spinning viscose into aqueous sulphuric acid.  As shown in Fig. 1, a filament 1 of this type is directed round the larger diameter hollow portion 4 of a rotatable sloping roller 2 and then travels over the remainder of the roller and fixed rod assembly 3 (the axes of which are mutually inclined) in a plurality of axially advancing helical turns, and finally passes to a winding device.  The roller is formed of or coated with an acid-resisting material such as a synthetic resin.  The rod assembly 3 may be of glass or of a synthetic plastic reinforced with glass fibre.  Water is directed drop by drop from the nozzle 5 on to the final turns of the filament on the roller 2 and, after flowing along the roller, passes through a ring of holes 6 into the interior of the hollow portion 4 of the roller, thereafter dropping into a trough 7 provided with a run-off 8.  As shown in Fig. 2, the rod assembly comprises three rods 9, 10, 11 mounted parallel to one another between two end plates 12, 13 to define the edges of a regular prism.  A pin 14 is secured to the centre of the end-plate 13 for the mounting of the assembly and for the adjustment of its position and may extend along the axis of the prism to the end-plate 12.  The axes of the roller 2 and rod assembly 3 are skewed or at an angle to each other as viewed in a horizontal plane and means are provided for adjusting this angle.  Means may be provided also for circulating hot or cold fluids through the roller, particularly cold fluids to counteract the heat generated when filaments carrying relatively concentrated aqueous solutions of sulphuric acid are washed with water.  The diameter of the roller preferably increases slightly, e.g. by 2-3 per cent, and gradually from the step in its lower position to a line A-B (Fig. 1) and thereafter preferably decreases, the diameter of the roller at its upper end being, for example, 5 per cent smaller than its diameter at the step.  The lower end of the roller is nearer to the rod assembly than the upper end. An additional stepped roller, the axis of which is inclined and skewed with respect to the axis of the first roller and which is shorter than the first roller, may be provided below the latter so that the filament first travels in a number of axially advancing helical turns over both rollers and thereafter over the upper roller and the fixed rod assembly only.  This permits substantial relaxation of the filament during its initial path of travel through the apparatus while it is still very plastic.  Specification 650,896 is referred to.