US2346696A - Manufacture of rayon - Google Patents

Description

Ap R8, M44., A. J. L. Mom-rz ETAL, 2,346,696

MANUFACTURE OF RAYON Filed March 5, 1940 8 Sheets-Sheet 1 PF E8; 944 A. J. L. MORITZ ET AL 2,346,696

MANUFACTURE OF RAYON Filed March 5, 1940 8 Sheets-Sheet 2 me/M3014 pri l, E944. A, J. l.. MORITZ x-:TAL 2,346,696

MANUFACTURE OF RAYON l Filed March 5, 1940 8 Sheets-Sheet 5 7b Spam 0,? c'aLLfJr//va swc PI 38; 1944 A. J. L. MORI-rz ETAL 2346,59

MANUFACTURE OF RAYON Filed March 5, 1940 8 Sheets-Sheet 4 April 18, 1944. A. J. l.. MoRlTz l-:T AL 2,346,696

MANUFAGTURE 0F RAYON Filed March 5, 1940 8 Sheets-Sheet 5 mi l HUI

A. J. L. MORITZ ET AL MANUFACTURE OF RAYON April 18, 1944.,

Filed March 5, 1940 8 Sheets-Sheet 6 III .www :um

April 18, 1944- A. ,1. 1 MORI- rz ET A1. 2,346,696

` MANUFACTURE oF RAYON Filed March 5, 1940 8 Sheets-Sheet 7 gmc/YM 8 Sheets-:Sheet 8 A. J. L. MORITZ ET AL MANUFACTURE OF RAYON Filed March 5, 1940 April 18, 1944.

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llateute'd-pr. 18, 1944 UNITED STATES PATENT or-'ElcE Adrian J. L. Moritz, Enka, and Arthur L. Jackson and Gilbert I. Thurmond, Asheville, N. C.. asslgnors to American Enh Corporation, Enka, N. C., a corporatlon of Delaware Application March 5, 1940, Serial No. 322.386

The present invention relates to the manufacture of rayon and, more particularly, to a process of and apparatus.for extruding solutions to form artificial mamentsthreads. yarns and the like.l

and for the subsequent handling and treatment thereof.

In the manufacture of threads of artificial origin, particularly in the production of viscose rayon, it is desirable that the threads have unlform physical and chemical properties. In fact. these properties, in some instances, are necessary in view of the high standards maintained in certain extremely competitive industries in which rayon is used For example, the weaving and knitting industries are particularly exacting in requiring thev artificial threads to be of a uniform character.

In the past, cotton has been the standard textile material used to reinforce certain rubber products such as cord tire carcasses. Recently, however, in addition toits wide use in the weaving and knitting industries, rayon has acquired an ever increasing importance for use as a reinforcement for rubber articles such as cord tires, heavy duty tires and the like, as well as for various other rubber products.

The rayon used in the rubber industry, if it is to give more satisfactory results as a reinforcement than cotton,`must have not only certain of the uniform characteristics required of it in the weaving and knitting elds but, ln addition, it mustl have a high strength, a low elongation, a high flexing life and other desirable characteristics.

In order to produce rayon having these characteristics required for its satisfactory use in the rubber industry, it was found necessary to modify the standard equipment previously used for the productiony of artificial threads. These modifications have necessitated a considerable amount of time-consuming research with the expense incident thereto.,

The standard equipment normally employed in the manufacture of rayon prior to its utilization as a reinforcement for rubber involves the use of a single coagulating or precipitating bath through which the laments are passed. After passing through this bath, the laments are stretched to a limited degree by passing them over a plurality of driven or freely rotatable rollers, stationary friction guides or the like. By this system, the yarn formed is then collected in package form, the impurities removed therefrom and the package dried. The disadvantages in this type of system is that the regeneration of the yarns is not complete and consequently the final threads produced are not sumclently strong or uniform in character to be suitable for lcertain uses. This is particularly true of rayon which is to be used as a reinforcement for -cord tires. heavy duty tires and the like.

There are several reasons for the fact that rayon produced by the standard equipment does not have the strength and uniformity required for its satisfactory use as a reinforcement for rubber. Perhaps the most important reason why the standard vequipment is unsatisfactory in this respect `ls the fact that it is not particularly adapted to stretch the thread ina uniform manner nor does it provide appropriate means for after-treating the thread prior to collection. Thus, the desirable qualities in a thread suitable for reinforcing rubber such as uniformity, high tensile strength, low elongation, high flexing life and the like are not attained in a thread produced by conventional equipment in the usual manner.

It has now been learned that if the rayon spinning system be constructed along lines which de part from the conventional type, the above-mentioned diiilculties are overcome. c Probably the most important change is in the use of a plurality of treating baths (at least two) containing acids, salts and/or water, at least one of the baths being maintained at an elevated temperature, for example, from to 90 C. lIn such a system, it is believed that the coagulation and' regeneration is vso adjusted that the regeneration per se is retarded but it is carried to completion in the several treating baths. By using the bath at the elevated temperature, a tremendously increased stretch can be effected thereby materially increasing the tensile strength of the individual laments making up the thread. The arrangement and specific application of the Ybaths is given more fully in the copending applications of Thurmond, Serial No. 259,261, and Muller, Serial No. 324,727.

Naturally, the use to which the thread is to be put determines the specific type of system to be employed. For example. inasmuch as it is necessary to produce a strong thread for use in the rubber industry, a plurality of specific treating baths are utilized, whereas in the knitting and weaving trade since it is of the utmost importance to provide uniform shrinkage, dyeing and other properties, specic baths of other typeswhich are not necessarily designed to imparthigh strength to the thread, may be used. It is, of clclaurse, desirable to have uniformity in cord tire t reads.

regenerating baths or treatments immediately y after the thread is extruded and prior to subsequent processing operations. To that extent the ilrst parts of the continuous" andthe continuous" systems are the same. After the thread has been initially treated in the foregoing manner it may then be continuously processed and dried prior to its collection or it may be immediately collected after complete regeneration and then given the necessary treating operations which include washing, desulphurizing, bleaching. rewashing and drying.

In practising the vpresent invention it has been discovered that the processing steps subsequent tothe passage of the filaments from the coagulating bath may be performed by the utilization of a subsequent bath or baths or by the application of the treating liquid or liquids through the medium of a spray.

It is an object of the present invention to provide a spinning system in which a predetermined amount of high stretch is imparted to the thread during or prior to complete regeneration as a result of a series of gradual stretching operations so that a high degree of uniformity is effected.

This invention further contemplates the provision of spinning apparatus for accomplishing the above referred to results which includes various combinations of godets, conical rollers and cylindrical rollers in their proper sequence, the conical rollers and cylindrical rollers being utilized to convey the thread in a multiplicity of helices and the conical rollers also imparting a gradual stretch to the thread.

Another object of the present invention provides for a series of treatments of the yarn as it is being passed in closely spaced, helical form on the rollers.

This invention contemplates additionally the application of a liquid to the thread being treated which liquid has been preheated or heated by contact with the roller over which the thread is guided, or both of these heating operations may be employed.

It is also an object of the present invention, when the processing steps employed involve the use of a hot bath, to provide a mechanism by which the lower roller of a pair provided for immersing the thread, is mounted for rotary displacement in order to facilitate the threadingin.

This invention also contemplates the use of a stop to prevent the thread from feeding in spaced helices all the way to the larger ends of cones forming a thread-storage, thread-advancing, thread-stretching device, until after lthe lower cone has been rotatably displaced into a treating bath.

Other objects and advantages of the invention will be apparent from the followingdescription, when considered in connection with the accomvPanying drawings, wherein portion of an interrupted type spinning apparatus constructed in accordance ,with this invention;

Figure2 is across-sectional view throughaportion of the apparatus shown in Figure 1 modified by therinclusion of .drivenl godet between the spinning bath and the conical stretching rollers;

Figure 3 is a view similar to Figure i and illustrates a further modified form of interrupted spinning apparatus, the apparatus including for cooperation with each spinneret a draw-of! godet and a driven godet in sequence in the path of travel of the thread to the conical stretching rollers for cooperation therewith;

lFigure 4 illustrates a cross-section through a continuousV type spinning apparatus formed in accordance with one principle of the present invention wherein the threads are drawn from the spinning bath and over freely rotatable, guiding rollers by means of nical rollers on which they are stretched, and immediately subjected to further treatments on storage devices;

Figure 5 is a sectional view similar to Figure 4 and shows a modified type of apparatus in which a draw-oi! godet is positioned between the spini ning bath and the conical rollers and in which further treatment of the threads is effected on rollers which convey them in helical fonn while a treating liquid is sprayed thereon;

Figure 6 is also asectional view through a portion of a continuous spinning apparatus and the apparatus therefor is a modiiication'of ythe one shown in Figure 5 in that, the conical rollers are replaced by cylindrical rollers and the threads are propelled under the desired degree of tension according to the relative peripheral speeds of a draw-of! godet, an adjacent driven'godet and the cylinders;

Figure 7 is a schematic view illustrating a spinneret, spinning bath and processing rollers of a continuous spinning apparatus in winch conical stretching rollers are mounted above the bath and treating liquid is sprayed on the thread being conducted along the rollers; v

Figure 8 illustrates the manner in which the lower rollers of those pairs of rollers which are utilized for immersion in a treating bath, are mounted for rotary displacement to facilitate threadingin"; and

Figure 9 is an enlarged sectional view taken on the line 9.-! of Figure 8 showing the upper roller in elevation, illustrating the latch means for retaining the lower roller in operative position and means by which the axes of the respective rollers may be adjusted with respect to each other to control the spacing of the convolutions of the threads as they are propelled in helical form.

With reference to the drawings, a frame of a spinning apparatus designated as i is provided with a channel bar 2 which extends along the length of the machine. Supported in front of channel bar 2 is a trough 3 which is adapted to contain a coagulating bath 4. A series of spinnerets are spaced lengthwise of the trough I, one of these spinnerets being designated at 5. The spinnerets i are each supported by a spinning solution supply line B which is connected to a filter 1. Filters 1 are pivotally supported at 8 in the customary manner to permit removal ofthe f spinnerets from the coagulating bath 4 for changing orcleaning.

After the solution is extruded from the spinneret illustrated, it is conveyed through the coagulating bath I in the form of a thread I, which thread,- in the form of apparatus illustrated in Figure 1, is drawn over freely rotatable guides Il and II supported upon abracket I2. Afterthe is passed from the led by roller I2 and then it around roller I8 and a roller I4 a plurality oi' times in order to stretch thesame. Rollers I8 and I4 are mounted so that roller I2 is positively driven while roller I4 is freely rotatable, the rollers being mounted in the manner illustrated in greater detail in Figure 9. ,Y

Roller I8 is provided with a splash shield Il to prevent acid from contacting the metallic parts constituting the housing. Roller I8 is ilxed to shaft I5 for rotation therewith and shaft I8 is supported in bearings I'I which are in turn secured in bracket I8 which is attached to a channel bar I8 supported upon an upwardly extending projection 2t on frame I. An opening 2I isprovided in the channel bar I 9 for each of the shafts I8 of the series arranged the respective spinnerets 5 and a lining 22 of the trough 8 covers the walls of said trough and then is extended downwardly over the outer i'acc thereof to a point where it overlies the channel bar I9. at which point the lining is formed to provide a cvering for a second trough 22 in which roller I4 is arranged to rotate within a bath 24. A plate 25 is clamped over the lining 22 adjacent the face of the channel bar I9 and an opening 25 is provided through the linlng` and plate 25 for the reception of a boss 21 of a tubular sleeve 28 which loosely encircles shaft I 9. Sleeve 28 is maintained in position by means oi a nut 29 which engages upon screw threads provided on said boss.

A hub 3l). provided with an arm 3i and a short extension 32 diametrically opposite to the arm, is secured lengthwise on the sleeve 28 which sleeve acts as a bearing therefor. Extension 32 is provided with one portion of a plvoted joint and is arranged to have secured thereto a lever 33, the lower portion of which level is provided with an opening 34 for the reception of a shaft 35 which is ilxed in position by a set 'screw 36. 'I'he upper portion of lever 33 encircles hub and lies behind arm 3|. Opening 3l is provided in arm 3l and has retained therein a loosely fitting bolt 38 which is provided with a grip 39 which in turn is threaded and pinned to the bolt. 'I'he head of the bolt 38 engages upon the inner wall of a shoulder formed by the reduction of the diameter of the opening 31. Bolt 38 is received in a screw threaded opening in the encircling portion of lever 33 and the angle of convergence of shafts I6 and 35 is readily adjusted by the rotation of bolt 38. A screw threaded cap 40 is adapted to be received in an enlarged recess overlying opening 31 in order to prevent longitudinal movement of the bolt 88.

The upper portion of arm 3I-is bifurcated and has pivotally mounted therein a latch member 4I which is normally biased to a position to engage within a slot. provided in a stop member 42, by means of an elastic latch member 43. Shaft ,I6 has iixed to the inner end thereof a bevel gear 44 which engages with a bevel gear 45 in turn keyed to a shaft 46 extending below the trough 3 throughout the length of the machine and which is adapted to be driven from a suitable source not shown.

When the rollers are in the relative position illustrated in Figure 9 and in the positions of the cuter assemblies shown in Figure 8 latch member 4I is engaged within the slot of the stop member 42 and the respective assemblies are secured in this position for operation.' However,

fo`r cooperation with v guide Il, itil propelil passed alternately vided with a rotatable during the threading-in" period. latch member 4I is removed frmn the slot of member 42 by depressing the outer'suriace `ol' the latch member below the pivot point and the hub and arm II with the latch member and pivoted lever 22 are rotated -about sleeve bearing 28 whereupon the latch member 4I is engaged in elastic latch memguide II and thence around roller I4. Immedi- :ltlelylafte lghreading-in, roller I4 together with e rea moved to the position as illustrated in Figure l.

A thread stop 41, arranged to b'pivoted in and out of'operative position upon a bracket 48, is provided for movement to the operative position during the threading-in" period. As the thread is initially wound upon the rollers, it tends to advance along the entire length of the rollers I3 and I4, but this is prevented by the stop 41. Such action is necessary in order to avoid domage or perhaps rupture of the thread. vbecause thethread'will'not normally withstand the stretch which would be imparted thereto by rollers I2 and I4 until the thread is wetted by the hot bath 24. Therefore the stop 4'I is maintained in operation until the thread is moved from contact therewith as lower roller I4 is being positioned in the bath. The rollers are each provided with a working surface of an acid-resistant material such as porcelain, glass, lacquered aluminum, Bakelite lor other resinous materials. As shown in Figure 9, the lower roller I4 is prohub 49 upon which is clamped a surface portion 50.

'I'he thread. upon reaching the end of the assembly of conical rollers as described. is then conducted from the roller I3 over freely rotating guides 5I and 52 whereupon, in the form shown lrii Figure 1, it is conducted to a collecting de- In Figure 2, a modied form of interrupted spinning apparatus is illustrated, in that, the thread 9, after being propelled through bath 4, is directed to and around a draw-oil godet 53. From the draw-olf godet, the thread is propelled to a conical roller assembly constructed as described in connection with Figures 1, 8 and 9 and, after being stretched `in a series of step-wise operations on the conical rollers I3 and I4, it is drawn over a freely rotating roller 54. The thread 9. after leaving roller 54, is conveyed to a collecting device which vmay be in the form of a bobbin or a centrifugal pot.

'I'he modiiled interrupted spinning apparatus illustrated in Figure 3 employs a godet 55 by which the thread is drawn `from the spinning bath 4 and the thread is propelled from godet 55 to another driven godet 56 arranged in the path of travel of the thread to the conical roller assembly associated with the second treating bath. Godets 55 and 55 are so arranged in the path of travel that the draw-off speed is maintained constant according to the peripheral speed of godet 55 and, after the thread is sufllciently cowhile being subjected to a second treating liquid it is stretched in a series of operations to the desired extent. The thread is then passed over a freely rotatingguide I1 whereupon it is collected in one of the normal collecting devices such as now in common use.

Continuous spinning apparatus are illustrated in `Figures 4 to '1. inclusive. Figures 5, 6 and 'I l'being modifications of the apparatus illustrated in Figure 4.

In the continuous spinning apparatus illustrated in Figure 4, the apparatus is identical with that illustrated in Figure l up to the point where the thread 9a is passed over a freely rotating guide 52a, although the compositions of the treating baths la and Na may be modified in accordance with the process hereinafter refer-red to in discussing the operation of the apparatus. After the thread is propelled from guide 52a, it is threadedupon rollers 58 and` 69 and a stop 60 similar to thread stop l1 is utilized, stop 60 being pivotally mounted upon a bracket. The thread is then continuously passed to the assembly which includes the upper and lower cylindrical rollers 55 and 59, after the lower roller 59 has been submerged within a treating bath 6I contained within a trough 62. The shaft 63 and 6l of rollers 5l and 59, respectively, converge toward the unsupported ends of the rollers in order that the thread will be conducted along the rollers in the form of a series of closely spaced helices. Rollers 58 and 59 and their .respective shafts 63 and 54 are mounted for movement in the same manner as rollers i3, il and shafts I6 and 35 shown in Figure 9 and described above. Thread 9a is propelled over freely rotating guides 55 and 55 after it is delivered from upper roller B whereupon it is directed to and over other processing rollers, the number of assemblies being controlled by the number of processing A thread is to be subjected. The additional processing of the thread 9a may be conducted on rollers of the type illustrated in Figure 4 or it may be conducted on rollers-which are not subl merged in a treating bath.

In Figure 5, there is illustrated a modication of a continuous spinning apparatus in ,which the thread 9b, in being propelled through a coagulating bath, is propelled by means of a draw-oi! godet 53h. 'The thread vis propelled around godet 53h and is thereafter conducted to a conical roller assembly of the type specifically illustrated in Figures 8 and 9 whereupon it is drawn over a freely rotating guide roller Mb to a cylindrical roller assembly designated generally at 51.

In assembly 61, upper and lower rollers 5l and 69 are mounted upon shafts 10 and 1i, respectively, and shaft 10, like shaft i5 as illustrated in Figure 9, is supported in bearings carried in bracket 12. Bracket 1A2,is supported upon channel bar 13 which is secured to the apparatus frame and a lining 14 extends down over the face oi' the channel bar. The shaft which has roller 58 keyed thereto extends through a tubular member 15 and then through the channel bar 13 and the supporting bearings. A bevel gear 15 is keyed to the end of the shaft 10 which gear meshes with a bevel gear 11 keyed to shaft 1l, and the shaft extends throughout the length of the apparatus and is operated from a source of power not shown.

The tubular member 15 is loosely engaged over the shaft and is secured in position -by a nut 19 which passes over a reduced portion of the member where it extends through openings in the linascenso mg u and a clamping piste n. ruealy to member 1l is an annular member ll which isv provided with upper-'and lower `extension l1 and Il. Lever Il is pivoted to the extension Il and has a'portion II whichencompassesthe annular member 8| and which lies behind extension 82. A bolt lt is threaded into portion l5 whichbolt has its head freely rotatable within extension 82. By adjustment of the boltv Il, lever `Il is caused to move about the pivot 81 in order that the angle of convergence of the shafts 10 and 1i may be modified to control the spacing of the helices of thread ibupon rollers Il and l. A spray pipe I8 extends throughout the length of the apparatus and it is provided with a spray nozzle 89 for each of the lower rollers of the respective assemblies and a drain pan ll having outlet pipes 9| is arranged to extend longitudinally of the apparatus forfthe purpose of conducting away or recycling the liquid sprayed from nozzles 89. Y

The thread 9b when it reaches the free end of the rollers of the assembly 61 is drawn over freely rotating guide roller 92 whereafter the thread '25 is conducted to and over other processing rollers in the manner described in connection with the thread leaving the apparatus illustrated in Figure 4.

Thread 9c as illustrated in Figure is subjected to the same general type of manipulation as is the thread 9b in Figure 5 except that the thread is conducted first to a draw-oil! godet i3 which acts to withdraw the thread from the coagulating bath at a constant speed. The thread leaving godet 93 is propelled to and around driven godet S4 whereupon a predetermined stretch of the thread is eifected. Upon leaving godet N, thread 9c is propelled to and around a cylindrical roller assembly designated generally as l5 n which is identical with the assembly last shown operations to which the in the path of travel of the thread in Figure 4. The cylindrical rollers of the assembly may be operated at a greater peripheral speed than the peripheral speed of godet Il whereby an additional stretch is imparted to the thread as it is passed to assembly 55, but otherwise the cylindrical rollers of assembly l5 merely act to eect a prolonged treatment of the thread as it is passed rin the form of a series of helices along the cylinders. over freely rotating guide roller 95 and to a cylindrical thread assembly designated generally as 91. Cylindrical, roller assembly 91 is identical In Figure 7 there is illustrated a modification of the continuous spinning apparatus described in connection with Figure 6 in that the thread 9d after it is extruded by the spinneret 5d is conducted through the coagulating bath ld and then immediately to the upper roller of a conical roller assembly designated generally as 90. Assembly 99 is formed with upper and lower conical rollers |00 and IUI and a pipe Ill! is arranged toextend longitudinally of the apparatus and'to have ex'- n tending therefrom a spray nozzle |03 for coope/ration with each of the assemblies i9, one of which is provided for cooperation with each of Thereupon the thread 9c is drawnthe spinnerets throughout the llength of the machine. The treating liquid which is sprayed from nozzle |03 is collected in a pan |04 and may be discharged or recycled for further use., Either roller |00, |I, or both may be provided with means for heating the same and with means for conducting the heating medium therefrom after it has served its heating purpose. Due to the utilization of the spray nozzles and the collecting pan itis unnecessary for the rollers |00 and |0| to be bodily movable with respect to each other for the purpose of threading-in and therefore the support and driving means for the rollers of the assembly 99 will be of the same form as utilized in connection with the roller assembly designated at 61 in Figure 5, and others.

The thread discharged from the lower roller |0| of assembly 99 is propelled to and a'round a driven godet |05 and therefore in addition to the stretch which is imparted to the thread in its passage through assembly 99 a further stretch may be imparted to the thread between roller |0| and driven godet |05 as a result of the driving of the godet at a greater peripheral speed than that of the large end of conical roller |0|. After the thread is propelledfrom driven godet |05 it is conducted to a cylindrical roller assembly designated generally at |06. Roller assembly |06 is provided with a spray nozzle |01 located between upper roller |08 and lower roller |09. The thread conducted to assembly |06 is passed first over roller |06 and then over lower roller |09 after which it is passed alternately around the rollers a, number of times in closely spaced helices. A pan I0 is provided below the assembly |06 and a pipe is positioned so that it extends longitudinally of the machine for supplying a treating liquid to the spray nozzle |01, one of which is positioned vfor cooperation with each unit |06 arranged along the length of the apparatus. The rollers of unit |06 are supported and driven in identically the same manner' as the rollers of assembly 61 sh'own in Figure 5.

After thread 9d is treated as described it is conducted over a plurality of assemblies similar to assembly 99 or assembly |06 and is subjected to different processing steps according to the type of thread being produced. It is thereafter dried, twisted and collected or rst collected and then twisted and dried.

In the operation, the initial spinning steps are generally the same in both the continuous system and the non-continuous or interrupted system. However, referring more particularly to the non-continuous system as disclosed in Figures 1 to 3 inclusive, and 7 and 8, the cellulosic solution is extruded into a precipitating or coagulatingl bath to form a thread or yarn consisting of a number of ine filaments. The composition of the bath is more or less standard, i. e., it contains sulphuric acid, sodium sulphate. zinc sulphate, magnesium sulphate and other salts, depending upon the conditions required for the'manufacture of the particular type of thread. 'I'he thread is passed through the coagulating bath, over freely rotatable rollers and thence to a pair of conical rollers where it is passed around the said rollers a multiplicity of times in the form of nely spaced helices. These helices are caused to pass to the large end of the rollers by means of the convergence of the axes of the rollers whereby the desired amount of stretch may be imparted by means of a sldewise, step by step, or increment stretching.

As an alternative to giving the thread the re-v purposes, the thread is led quired stretch by means of the conical rollers lper se, the thread may be passed'from the coagulating bath to one or more driven godets gliereby it is initially stretched, whereafter a `pplementary stretch may be imparted by means of the conical rollers. As shown in Figures 1, 2, 3 and 9, the lower conical roller ils caused to be rotated in a treating bath and owing to the fact that this second bath is preferably maintained at a high temperature, for example, in the range of from 70 C. up to 90 C. or even C.. it would normally be impractical or impossible for an operator to initially wrap the thread around the lower roller, as thiswould necessitate physical contact with the hot bath. Accordingly, when the thread is initially passed around the two rollers, the lower roller is first raisedout of the bath. Upon spinning-in, the thread is prevented from passing more than half the length of the rollers until after the lower roller has been submerged and put into operative position in the bath. Until the thread is actually contacted with the bath, it is impossible to impart the maximum stretch as it would rupture or break.

After the thread passes a. suiiicient number of times around the rollers in order to impart the required stretching and substantially complete regeneration, it is led by means of freely rotatable rollers to a suitable collecting device such as a bobbin or centrifugal pot. The thread in this condition is properly after-treated. In the case of spinning thread to be used for reinforcement of cord tires or other rubber articles, it is usually only necessary to thoroughly wash the thread and dry the same. The second bath may be comprised of pure hot water or it may contain a very dilute hot solution of acid or equivalent salts wherein a major proportion of the sulphur isremoved at the time the thread is completely regenerated. In some cases, it may be desirable to give the thread a treatment while on the conical rollers without immerslng the same in a bath. In such instances, spray pipes may be utilized in the same manner as that shown in the continuous process.

The foregoing treatment in the noncontinuous type of spinning imparts to the thread a maximum stretch and complete regeneration, whereby the product obtained is not only uniform in characteristics, but has unusually high strength. low elongation, high exing and other characteristics that render it particularly adaptable for use in reinforcing rubber articles.

Referring now to the continuous system for manufacturing thread of extremely uniform characteristics suitable for knitting and weaving through a coagulating bath of generally the same composition as that used in the non-continuous system. It is then passed to a pair of conical rollers either directly or by means of freely rotatable rollers or by one or more driven godets, or the thread may even be led to godets, stretched and then passed immediately to a pair of cylindrical rollers acting as storage devices. In this case, it is also readilyapparent that the desired stretching can be imparted either by means of the conical rollers or godets or combinations thereof. Although one or more of the treating baths may be heated, it is not essential, as in this type of spinning uniform characteristics are more important and certain uniformity of characteristics may be had by the continuous treatment on pairs ofrollers or storage devices in their proper sequence without the use of a hot bath.l The fact that the liquids do not have to be heated makes it possible to utilize as an alternative, a series of sprays. These sprays cause the treating liquid to be impinged upon the rollers and the thread contacted therewith. Of course when sprays are used as a substitute for baths it is not necessary to provide means for rotatably displacing the lower roller during the spinning-in" operation. The location and construction of the spray pipes may be modified to adapt them for the particular specific system used, for example, it may be desirable to locate the said pipes above the top roller or between them, or the spraying may be effected on both rollers. Moreover, a single spray jet for a roller may furnish sufiicient liquid on the roller to adequately treat the thread passing transversely across the face of the rollers.

After the thread has been coagulated, stretched and treated it is then passed to a series of cylindrical roller assemblies, the number of which, depends on the number of operations necessary to completely process and finish the thread. In one system after the thread is suitably coagulated, it is washed either by bath or by spray while on a pair of rollers, desulphurized on an immediately succeeding lpair of rollers and then successively again washed, bleached, purified, 'rewashed, dried and finally twisted while being collected in the form of a cop, cone, or the like.

Referring more particularly to Figure '7, the thread is propelled from the coagulating bath by means of the conical rollers on which it is stretched and treated with a dilute acid bath, after which it may be further stretched on godets and led to successive cylindrical rollers for the further processing operations. or both of the conical rollers may be internally heated if it is desired to raise the temperature of the treating solution.

It is to be understood that a number of modifications may be made in both systems without departing from the spirit of the invention. In the figures, the lower roller has been shown as freely rotatable, or that is, driven by the thread per se. These lower rollers, if desired, may be driven either by means of a belt connected with their respective upper rollers, or by a separate driving mechanism. In the type of system where sprays are employed instead of baths, sprays on certain of the rollers may be entirely omitted whereby the purpose of that particular pair of rollers is to merely prolong the passage of the thread undergoing regeneration. It has been determined in some instances that the sprays may be omitted from the first pair of conical rollers on which the thread is stretched. In this case, the thread is merely further coagulated during the stretching operation. It is to be also understood that any parts of the system coming into contact with acids or alkali either directly or indirectly, are formed of non-corrosive materials.

While the apparatus employed in the system illustrated in the respective figures of the drawings may be operated in a number of different specific ways so as to materially change the character of the particular threads being produced, for the purpose of exemplification, several specific operations will now be set forth.

Example I 6.7% NaOH. The solution was extruded at the 75 In this case, one

audace rate of 70 meters per minute into a spinning bath containing HzSO4, NazSO4, MgSO4 and ZnSO4. The spinneret utilized produced the 120 filament type thread and the thread was stretched approx- 5 imately 7% as it was drawn to a conical roller whereupon it was subjected to a second liquid treatment, the said liquid containing about 1.0% H2SO4 carried over from the first bath and maintained at a temperature above 70 C. The conical roller was one of a pair over which the thread was conducted in a series of helices due to the axes of the rollers being converged so as to effect a multiplicity of stretching operations in the thread during its progression around the rollers. l5 Due to the shape of the cone and the positioning of the axes thereof, the thread was progressively stretched approximately 65%. In the operation just described, the apparatus was threaded-in in the manner hereinbefore discussed. The thread was then conducted to a centrifugal pot collecting device and a cake about one inch in thickness was built up. Thereafter, the cake was subjected to washing, desulphurizing, etc. 'I'he thread after drying was tested and found to have 15% elongation and 370 grams tensile strength per denier.

Example II In one operation conducted with the apparatus illustrated in Figure 2 whereby the yarn was produced, a spinning solution and spin bath of the same composition set forth above with respect to Example I was employed, and the 'thread was drawn off by a driven godet at a speed of approximately 40 meters per'minute, whereupon the thread was stretched to 15% between the driven godet and a conical roller of a pair, the smaller end of which roller was operated at a greater peripheral speed than that of the driven godet. Upon the immersion of the thread in a second bath that was of the same composition as that set forth with respect to Example I, the thread was propelled over the conical rollers in the manner heretofore stated and it was here given an additional stretch which resulted in the thread having a total stretch of 70%. The thread was thereafter subjected to washing, desulphurizing, bleaching and drying in the manner stated with respect to Example I and the thread tested had essentially the same characteristics as in Example I.

Eample III .65 like, comprising extruding a viscose spinning solution as a multiplicity of filamentsinto a coagulating bath to precipitate and partially regeneratel the same, withdrawing the filaments from the bath by means of a driven godet, then conducting the same alternately over a driven roller and a freely rotating roller which form a thread-storage thread-advancing device, and contacting the filaments with a regenerating treating liquid in a bath other than the coagulating bath as they travel over one of the rollers, said filament path being in the form of a series oi' helices, and so extended that the filaments are substantially completely regenerated when they additional stretch during further regeneration thereof. Y

2. A process of producing artificial yarn involving the use of a spinneret, a. spin bath, a second bath and a pair of rollers forming a yarnstorage yarn-advancing device of whichone roller while being normally adapted for rotation in the second bath, is adjustable to a position for rotation above the bath, comprising the steps of removing the adjustable roller from the bath and directing filaments as they are extruded from the spinneret and then withdrawn from the spin bath alternately around the rotating rollers a plurality of times in the form of `a series of helices, immersing the adjustable roller in said second bath, and then continuing the propulsion of the laments along the pair of rollers, and maintaining the said second `bath at a temperature of at least 60 C.

3. A process of producing artificial yarn inrolving the use of a spinneret, a spin bath, a second bath and a pair of cone rollers forming a yam-storage, yarn-advancing, yam-stretching device of which one roller while being normally adapted for rotation in the second bath is adjustable to a position for rotation above the bath-comprising the steps of removing the adiustable roller from the bath and directing filaments as they are extruded from the spinneret and then withdrawn from the spin bath alternately around only the smaller portions of the rotating rollers a plurality of times in the form of a series of helices, immersing the adjustable roller in said second-bath, and then continuing the propulsion of the filaments over the pair of rollers while eiecting the spacing of the helices along substantially their entirety and maintaining the said second bath at a. temperature of at least 60 C., whereby the yarn is subjected-to the maximum stretch which is imparted by the cone rollers only after it is contacted with the second bath.

4. In an apparatus for producing articial yarn which includes a spinneret, a trough for retaining a spin bath, a second trough for retaining a bath, a yarn-storage, yarn-advancing device for propelling yarn in the form of a series of helices While it is .in contact with the bath in the second trough, said yarn-storage, yam-advancing device comprising a pair of rollers over which the filaments are alternately directed, a driving shaft for one of the rollers, a shaft by which the other roller is rotatably mounted, one of said shafts being iixedly located above the bath contained in the second trough while the other I shaft is carried by an arm `which is pivotally mounted and adapted to have its end carrying the shaft moved through a path for effecting the positioning of the shaft and its roller within the bath during operation of the apparatus and above the bath while the yarn is being threaded thereupon, and means for adjusting the axis of one shaft with respect to the other shaft to thereby cause the yarn Ato be propelled along the rollers in a path formed of a series of helices in which the helices are spaced a predetermined distance.

5. In an apparatus for producing artificial yarn which includes ia spinneret,- a trough for retaining a spin bath, av second trough for retaining a bath, a yam-storage, yarn-advancing device for propelling yarn in the form of a series oi helices while it is in contact with the bath in the second. trough, said yarn-storage, yarn-advancing device comprising a pair of rollers over which' the yarn is alternately directed. a driving shaft for one of the rollers xedly located above the bath contained in the second trough, a sle'eve encircling said shaft and acting as a bearing for a rotatably mounted member having an arm radially extended therefrom, y

a shaft secured to the free end of said arm on which the other roller is rotatably mounted, said shaft carried by the arm due to the rotation of the member from which the arm extends causing the shaft tobe moved through a path for the positioning ofthe shaft and its roller within the bath during operation of the apparatus and above the-,bath while the yarn is being threaded thereupon, and means for adjusting the axis of one shaft with respect to the otherV shaft to thereby cause the yarn to be propelled along the rollers in a path formed of a series of helices in which the helices are spacedv a predetermined distance.

6. In an apparatus for producing artificial yarn which includes a spinneret, a trough for *retaining a spin bath, a second trough for retaining a bath, a yarn-storage, yarn-advancing device for propelling yarn in the form oi a series of helices while it is in contact with the bath in the second trough, said yarn-storage, yam-advancing device comprising a. pair of rollers over which the yarn is alternately directed,

a driving shaft for one of the rollers ixedly located above the bath contained in the second trough, a sleeve encircling said shaft and acting as a bearing for a rotatably mounted member having an arm radially extended therefrom, a shaft secured to the free end of said arm on which the other roller is rotatably mounted, said shaft carried by the arm due to the rotation of the member from which the arm extends causing the` shaft to be moved through a path for the positioning of the shaft and its roller within the bath during operation of the apparatus and above the bath while the yarn is being threaded thereupon, latching means for securing the rotatable member with its extended arm in the positions of adjustment, and 'means for adjusting the axis of one shaft with respect to the other shaft to thereby cause the yarn to be propelled along the rollers in a path formed of a series of helices in which the helices are spaced a predetermined distance.

7. In an apparatus for producing artiicial yarn which includes a spinneret, a trough for retaining a spin bath, a second trough for retaining a bath, a. yarn-storage, yarn-advancing device for propelling yarn in the form of a series of helices while itis in contact with the bath in the second trough, said yam-storage, yarn-advancing device comprising a pair of rollers over which the yarn is alternately directed, a driving shaft for one of the rollers fixedly located above the bath contained in the second trough, a sleeve encircling said shaft and acting as a bearing for a. rotatably mounted hub member which has an arm radially extended therefrom. a second arm extending from the hub member diametrically opposite to the rst mentioned arm, a lever pivotally extending from said rst arm, a shaft secured to the free end of the lever on which shaft theA other roller is rotatably mounted, the lever having an extension which overlies the second arm, said shaft carried by the arm due to the rotation of the member from which the arm extends causing the shaft to be moved through a path for the positioning of the shaft and its roller within the bath during operation of the apparatus and above the bath while the yarn is being threaded thereupon, latehing means for securing the rotatable member with its extended arm in the positions of adjustment, and means connecting the overlying arm of the hub member andthe lever for moving them relative to each other thereby to adjust the axis of one shaft with respect to the other shaft and cause the yarn to be propelled along the r'ollers in a path formed of a series of helices in which the helices are spaced a predetermined distance. l

8. In an apparatus for producing artificial yarn which includes a spinneret, a trough for retaining a spin bath, a second trough for retaining a bath, a yam-storage, yarn-advancing, yarn-stretching device for propelling yarn in the form of a series of helices while it is in contact with the bath in the second trough. said yarn-storage, yarn-advancing, yarn-stretching device comprising a pair of cone rollers over which the yarn is alternately directed, a driving shaft for one of the rollers flxedly located above the bath contained in the second trough, a sleeve encircling said shaft and acting as a bearing for a rotatably mounted member having an arm radially extended therefrom, a shaft secured to the free end of said arm with which the other roller is bodily movable and on which it is rotatably mounted, said shaft carried by the arm due to the rotation of the member from which the arm extends causing the shaft to be moved through a path for the positioning of the shaft and its roller within the bath during operation of the apparatus and above the bath while the yarn is being threaded thereupon, a stop for engaging the yarn to prevent its passage entirely along the cone rollers only when the movable roller is positioned above the bath, and means for adjusting the axis of one shaft with respect to the other shaft to thereby cause the yarn to be propelled substantially entirely along the rollers in a path formed of a series of helices in which the helices are spaced a predetermined distance when the bodily movable roller is positioned in the bath.

9. In an apparatus for producing articial yarn which includes a spinneret, a trough for retaining a spin bath, a second trough for retaining a bath, a yarn-storage, yarn-advancing, yarnstretching device for propelling yarn in the form of a series of helices while it is in contact with the bath in the second trough,.said yam-storage, yarn-advancing, yarn-stretching device comprising a pair of rollers over which the yarn is alternately directed, a driving shaft for one of the rollers xedly located above the bath contained in the second trough, a sleeve encircling said shaft and acting as a bearing for a rotatablymounted member having an arm radially extended therefrom, a shaft secured to the free end of said arm on which the other roller is bodily movable and on which it is rotatably mounted, said shaft carried by the arm due to the rotation of the member from which the arm extends causing the shaft to be moved through a path for the positioning of the shaft and its roller within the bath during operation of the apparatus and above the 4bath while the yarn is being threaded thereupon, a stop for engaging the yarn to prevent its e entirely along the cone rollers only when the movable roller is positioned above the bath,- latching means for securing the rotatable member with its extended arm in the position of adjustment. and means for adjusting the axis of one shaft with respect to the other shaft to thereby cause the yarn to be propelled substantially entirely along the rollers in a path formed of a series of helices in which the helicesare spaced a predetermined distance when the bodily movable roller is positioned in the bath.

10. In an apparatus for producing artificial yarn which includes a spinneret, a trough for retaining a spin bath, a trough for a second bath, a yarn-storage, yarn-advancing, yarn-stretching device for propelling the yarn after it is passed from the spin bath in the form of a series of helices. said device comprising a pair of cone rollers over which the yarn is alternately directed,

one of which rollers is normally immersed in the second bath while the other rotates thereabove, a

driving shaft for one 4of the cone rollers, a shaft by which the other cone roller is rotatably mounted, and means for adjusting the axis of one shaft with respect to the other shaft to thereby cause the yarn to be propelled along the rollers in a path formed of a series of helices in which the helices are spaced a predetermined distance,

the said cone roller above the bath being vprovided with a splash plate at its inner end to substantially prevent the liquid from the bath from coming into contact with the remainder of the apparatus. jf

ADRIAN J. L. MORITZ.

ARTHUR L. JACKSON. GILBERT I. THURMOND.

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