Patent GB-576724-A (GB)
Title: Improvements in process and apparatus for the manufacture of artificial threads
IPC: D01D10/04
Filed: 1943-08-10
Abstract: <PICT:0576724/IV/1> Artificial threads are continuously manufactured by advancing the freshly wet spun threads in a helical path through spaced zones of different after-treating liquids formed on the periphery of a roller, the surface of the roller having recess means serving to accumulate and separately discharge the treating liquid from each zone during rotation of the roller.  The threads are advanced over a pair or pairs of rollers having zones to which treating liquids are applied.  Treating liquid may be applied to the roller surface from a source external or internal thereto and in the latter case the roller surface is provided with apertures to permit passage of liquid from the interior thereof.  The length of each zone corresponds to the time factor dictated by chemical necessity and in each zone a liquid is supplied in an amount and at a rate and temperature correlated with the length of the zone. The process is applicable to threads spun from solutions of viscose, cuprammonium - cellulose, cellulose esters or polymerized hydrocarbons and derivatives thereof, and provides for the continuous manufacture of wet spun threads, fully after-treated, dried, sized, and twisted to a controlled extent. A spinning machine includes a number of spinning units each consisting basically of a spinneret 10, Fig. 1, and a pair of thread advancing devices 11, 12, upon which the thread is subjected to all required after treatments.  The <PICT:0576724/IV/2> <PICT:0576724/IV/3> <PICT:0576724/IV/4> <PICT:0576724/IV/5> thread is finally twisted and collected on spindle 13.  The spinnerets 10 are disposed in a single spin bath 14 (Fig. 2) which extends for the full length of the machine, while pumps 15, all of which are driven from a common source, supply spinning liquid through filters 16 to the spinnerets 10.  The thread, leaving bath 14, is passed around godets 31 and then, either directly to unit 11, or through the hot water or hot acid bath 34 and then to unit 11.  Each unit 11 and 12 comprises two rollers 45, 46 and 126, 127 respectively, each pair of rollers being driven at the same peripheral speed, the take-up speed of unit 12 being approximately the same as the delivery speed of unit 11. The axes of rollers 46 and 127 are horizontal while those of rollers 45 and 126 are slightly inclined to those of 46 and 127.  Thread wound around the pair of rollers 45, 46, or 126, 127, progresses towards their unsupported ends, the spacing of adjacent connected coils of thread being a function of the angle of convergence of the rollers.  This angle also determines the number of coils in units 11 and 12 at any given time, which, in turn, controls the duration of any treatment they may receive during passage thereover.  The position of axes of rollers 45 and 126 is, therefore, rendered adjustable, by means denoted generally at 63 and 139 respectively. Thread is led over guide roller 68 to the unit 11 and leaves it under roller 70, from which it passes over roller 71 to the thread-advancing unit 12.  To assist in threading up the machine the free end of thread from unit 11 is led to the rotating temporary collecting device 77, driven by motor 80.  The device 77 is bodily moved across the machine so that it is positioned adjacent the supported end of unit 12.  The thread is then broken from device 77 and unit 12 is readily threaded-up.  In order that a plurality of adjacent pairs of units may be threaded up with maximum convenience, another temporary collecting device <PICT:0576724/IV/6> 81, driven by motor 82 is offset from device 77 at a distance equal to the space between the axes of adjacent units (see Fig. 2).  The temporary collecting devices 77 and 81 are normally disposed on opposite sides of the machine, so that when device 77 is overlying a unit 11, a device 81 is in a similar position over an adjacent unit 12.  Bodily movement of devices 77 and 81 across the machine is effected by the concurrent and intermittent rotation of oppositely threaded screws 83, 84, driven by reversible motor 93.  The devices 77 and 81 are also subject to bodily movement lengthwise of the machine.  The devices are mounted on car 103 adapted to ride on rails 106, 107, and driven thereon by motor 115 through rack and pinion 110-111. Lengthwise movement of the car is controlled so that it is moved a distance equal to twice the distance between the centres of adjacent units without the necessity for spotting it.  This movement is effected by so arranging the diameter of pinion 110 that one revolution thereof will move the car exactly the desired distance, after which motor 115 is automatically de-energized.  The motor is re-started by switch arms 119, 120, which may be operated from either side of the machine by pullcords.  Rollers 45 and 46, of unit 11, each comprise two cylinders 209, 210 and 212, 213 (Fig. 12), separated by annular members 211 and 214 respectively. Treating liquids are applied to the surfaces of the cylinders by spray pipes 231, 232, 233 and 234.  Thus the same <PICT:0576724/IV/7> <PICT:0576724/IV/8> <PICT:0576724/IV/9> liquid may be applied by pipes 231, 233 to cylinders 209, 212, while a different liquid may be applied from pipes 232, 234, to cylinders 210 and 213.  The uniform distribution of a film of treating liquid over the surface of cylinders 209, 210 and 213, as well as the rate of axial movement of such liquids is controlled by grooves 235, 236 cut in the cylindrical surfaces.  The films of liquid move towards the supported ends of the rollers 45 and 46 and intermixture of liquids is prevented by annular members 211 and 214 which are exteriorly grooved.  Partitions 237, 238, in troughs 69, 72, extend under the respective central grooves of annular members 211 and 214 so that liquids discharged from adjacent cylinders may be separately recovered.  Rollers 126, 127, of unit 12 (Fig. 13) comprise cylinders 248, 250, 251 separated by annular grooved <PICT:0576724/IV/10> <PICT:0576724/IV/11> <PICT:0576724/IV/12> <PICT:0576724/IV/13> <PICT:0576724/IV/14> members 252 and 253, and cylinders 263, 266, 265 and 264 separated by annular grooved members 268, 267 and 261 respectively, to which treating liquids may be applied through spray pipes 270, 269, 273, 272, 271, each liquid being separately recovered in troughs 274 and 277 below the cylinders.  Cylinders 250 and 266 are provided with grooves 280 while cylinder 251 has grooves on the side nearer the annular member 253.  A portion of cylinder 251 near its unsupported end is provided with a heating unit 283 which serves to dry the treated threads on the surface of the cylinder.  A heat insulated disc 284 and cooling zone 285 prevent radiation and conduction of heat along the roller 126.  The grooves 280 are disposed helically about the surface of the cylinder at an angle #q to the plane at right angles to the cylinder axis (Fig. 14) so that the control of liquid flow in an axial direction is dependent upon the magnitude of angle #q.  The grooves are provided with flared portions 282 so as to distribute a film of liquid over the surface of the cylinder.  In order that liquid films on the surface of coacting cylinders, e.g. cylinders 250 and 266, shall move at the same rate, grooves on cylinder 250 have a greater helix angle than grooves on 266, thus compensating for the fact that upper cylinder 250 is not horizontal. Annular member 253, which is typical of all other annular members is provided with four annular grooves 293, 294, 295 and 296 (Fig. 23). Grooves <PICT:0576724/IV/150> 293 and 294 serve to collect and discharge liquid from cylinder 251 whilst groove 296 serves to discharge any liquid which may creep from right to left on cylinder 250.  Separating groove 295 is normally dry at all times.  The peripheral speed of roller 126 is so correlated with its diameter that liquid will only be discharged from annular member 253 in its movement below a horizontal plane passing through the centre of the roller.  A plurality of circumferentially spaced bridges 297 are disposed above annular member 253 and serve to support the thread as it passes over the annular grooves.  The upper surface of each bridge is curved and raised from the cylinder surface so that the polygonal path of the thread thereon is equal to its arcuate path on the adjacent cylinder.  The cylinders may be composed of stainless steel or a carbon and graphite composition.  In a modified type of spinning machine (Fig. 29) assembled in conjunction with a two-bath system, the thread leaving the spinneret 304 is passed over a long path guiding device 305 and godet 306 to thread-advancing units 307 and 309.  A modified means for mounting and adjusting the position of upper roller 333 of unit 307 is denoted generally by 384 and 352.  A rocker arm 367 (Fig. 30) is provided for the purpose of moving a temporary collecting device 368 across the machine.  Unit 309 (Fig. 29) comprises two rollers 380 and 381.  The upper roller 380 is supported in bearings 384 mounted on plate 384a which is pivoted at 391, and its axis is rendered angularly adjustable by means denoted generally at 393.  To assist in threading up unit 309, liquid collecting trough 400 is pivoted at 402, and thus it may be lowered by bellcrank 405.  Trough 417 may similarly be adapted to be lowered. In a modified thread-advancing unit (Fig. 35) lower roller 446 is provided with a plurality of annular flanges 461 dividing the interior into a number of zones of differing axial length.  A plurality of spray pipes 462 extend into the cylinder 446, each pipe being led to a different treatment zone.  Between partitions 461, apertures 463 are provided in the surface of cylinder 446 which are in registry with the bottom of grooves 464 (Fig. 37).  Thus, liquid is supplied to the interior of the cylinder, passes through apertures 463 and is distributed over the cylinder surface by grooves 464.  The boundaries of the treat