US2243116A - Apparatus for use in manufacturing artificial filaments - Google Patents

Description

y 1941- w. OSTE RMANN 2,243,116 APPARATUS FOR USE IN MANUFACTURING ARTIFICIAL FIL'A'MEN'I'S Filed March 8, 1937 Patented May 27, 1941 APIARATUS FOR USE IN MANUFACTURING ARTIFICIAL FILAMENTS Walter Ostermann, Wuppertal-Barmen, Germany, assignor to American Bemberg Corporation, New York, N. Y., a corporation of Delaware Application March 8, 1937, Serial N 0. 129,541 In Germany March 9, 1936 12 Claims.

The present invention relates to the manufacture of filaments of artificial origin but more specifically has for its purpose to devise a novel method of and apparatus for the spinning of such filaments.

Ln the spinning of artificial filaments by the wet-spinning process a spinning solution is extruded through the openings of a spinnerette nozzle, which may be immersed in a precipitating medium, and the spinning solution, as it is extruded from the openings of the spinnerette, is precipitated by the medium or bath, and the thread or filaments are thus formed.

In the Wet-spinning of artificial filaments, such, for example, as by the cuprammonium process, spinnerettes having comparatively small openings are employed and the spinnerettes immersed in precipitating baths, such as sulphuric acid or caustic soda solutions, which quickly coagulate the filaments as they are extruded in the said bath. In some instances it is desirable to have these baths flow in a trough, which is approximately horizontal, and from one end of the machine to the other the threads being drawn vertically from the bath. This method of spinning does not result in uniform coagulation of the filaments from spinning station to spinning station, due to the change in concentration of the bath as it flows past the different spinning stations.

It is therefore one purpose of the present invention to provide an arrangement to overcome the aforementioned disadvantage by surrounding each spinning nozzle with a funnel arrangement and providing nozzles from which fresh precipitation liquid is supplied in the direction of travel of the thread. A novel feature of the present invention consists in a pipe-like insertion which is positioned in the precipitating bath trough and concentrically around the thread, together with nozzles from which fresh precipitating liquid is supplied in the direction of travel of the extruded thread.

The liquid stream ejecting from the nozzles and into the funnel device produces a positive flow of the spinning bath therethrough. A continuous renewal of the spin bath arotmd the spinnerette and at the point of extrusion of the freshly spun thread results from the arrangement. The flow of the spin bath in the direction of travel of the filaments aids in the stretching and strengthening of the freshly extruded thread.

It is therefore one object of the present invention to provide uniform spinning conditions at all spinning stations of a spinning machine.

Another object of the present invention is to provide an arrangement and method whereby stretching or strengthening of the freshly extruded threads results.

Important features of the invention in its preferred form comprise providing a continuous supply of fresh precipitating medium adjacent the extrusion nozzle and causing the precipitating medium to fiow in the direction of travel of the freshly extruded threads.

Other objects will become apparent.

Referring to the drawing, Figure 1 shows a diagrammatic vertical cross-section of a spinning machine with one embodiment of the invention opcratively positioned therein. Figure 2 is a view similar to Figure 1 illustrating a modified form of the invention.

In the drawing in which like numerals of reference indicate like parts, I refers to the usual type of spinning pipe including a candle filter and having attached thereto a spinnerette 2. The spinning pipe I is pivotally mounted as indicated at la in the usual manner whereby it may be swung into and out of the spin bath trough 3 and the liquid contained therein.

The wall 4 of the spin bath trough 3 has attached thereto a spin bath supply pipe 5. The spin bath enters the trough 3 through a plurality of nozzles positioned annularly around the spinning nozzle 2, two of which are illustrated at 6.

A funnel-like member I is positioned in the spin bath trough 3 and concentric to the spinning nozzle 2. The precipitating liquid is forced, together with the thread 8, through the conical insertion tube 7 and into the tapered portion 9 of the latter.

The thread 8 as it issues from the spinning nozzle is drawncentrally through the funnel l and around a guide roller H] which may be partially submerged in the spin bath. This roller in the embodiment illustrated is freely rotatable and driven by the thread drawn around it, but, if desired, it may be a positively driven roller. The thread is drawn from there to a suitable take-up device (not shown). The guide roller Ill is preferably positioned adjacent the tapered end 9 of the funnel l.

The fresh spin bath coming from the nozzles 6 is forced to flow in the direction of travel of the thread 8 by reason of the funnel I.

An overflow I6 is provided whereby the used spin bath may be carried off at the same rat at which it is supplied.

A flange H which may be formed integral to the outside of the funnel l is provided for the purpose of uniformly positioning the said funnel l in the supporting frames I2 and 13. Of course, other means may be provided for accomplishing this purpose.

In operation the roller I is first moved into the position shown in dotted lines in Figure 1. The funnel is lifted from the frames 12 and 13. The spinnerette together with the spinning pipe I and spinnerette 2 may be swung out of the trough, as shown in dotted lines, for cleaning or changing of the spinnerette. After the cleaning or changing operation, the spinning pipe l and spinnerette 2 are swung back again into the precipitating bath. The funnel 'l is placed in position on the frames I2 and I3, and surrounding the spinnerette 2 and the spinning operation is then begun.

The thread bundle 8 is pulled through the mouth of the funnel by any suitable means such as, for example, a hook. After the thread has been pulled through the funnel I the roller i0 is moved into the position, shown in full lines, and at the same time the thread 8 is led to a winding device. After the roller H! has been placed in position, a locking pin 14 is positioned in place on a bracket l and holds the said roller l0 in the spinning position.

In Figure 2 is illustrated a modified form of the invention. In this instance the spinnerette 2| which is mounted on a spinning pipe 2Ia. can be swung into and out of spinning position on its pivot 2lb the same as described with relation to Figure 1.

In this form of the invention, the spinnerette 2i discharges vertically and the thread 30 is drawn therefrom in a vertical direction.

The funnel 23 which is positioned concentrically around the spinning nozzle has an annular enlargement 22 which rests on the circular bracket 24 and is supported thereby. The bracket 24 is pivotally mounted at 25 on the side of the spin bath trough 26.

The trough 26 has a closed chamber 2'! formed in the bottom thereof and to which the fresh spinning bath solution is fed under pressure through a pipe 3!. Nozzles 28 are positioned adjacent the spinning nozzle 21 and are the outlets through which the spin bath solution is forced from the chamber 21. These nozzles may consist of two or more nozzles arranged concentrically around the spinning nozzle.

By reason of this structure, a constant flow of fresh spinning solution passes upwardly past the spinning nozzle 2| and along the funnel 23, whereby a strong upward circulation of the spinning liquid is produced.

The spin bath then overflows the upper edge of the funnel 23 and into the spinning trough 26, A portion of it overflows from the trough and the remainder is circulated again upwardly through the funnel 23.

An overflow 29 is provided whereby the used spin bath liquid is discharged at the same rate at which it is supplied.

To start the spinning operation, the funnellike insertion 23 is swung out of the bath on the pivot 25, The spinnerette 2| may then be swung on its pivot 2H) for the purpose of exchanging spinning nozzles and after the spinning solution begins to emerge the spinnerette is swung back into the bath. The funnel 23 and its support 24 are swung on the pivot 25 down to a point where the funnel may surround the spinning nozzle 2|.

The extruded thread bundle is then led to a winding device in any well known manner (not shown).

The form of the funnel insertion may be either substantially cylindrical or substantially conical. The effect on the freshly extruded thread depends upon the conicity of the funnel, i. e., whether the diameter of the funnel decreases or increases in the direction of the travel of the thread.

If the diameter of the funnel decreases in the direction of travel of the thread, an acceleration of the flow of precipitating liquid in this direction takes place. This acceleration of the flow of the liquid exerts a stretching action on the thread in addition to that which would result from the flow of liquid from the nozzles through a cylindrical tube. If, on the other hand, the diameter of the funnel becomes greater in the direction of travel of the thread, the speed of the spinning bath will gradually decrease. In this instance, the stretching of the thread takes place owing to increased friction on the spinning bath liquid, which resists the drawing of the thread by the rotor or other drawing device. At the same time continuous removal of the bath in the vicinity of the spinning nozzle is maintained.

The funnel insertion, whether cylindrical or conical, may be positioned various distances from the spinnerette. It is advantageous to position the spinnerette either completely or partially within the funnel. If it is desired to maintain uniformly the direction of travel of thread in the said funnel a thread guide may be provided at the mouth of the funnel as shown at It in order to direct the passage of the thread to the take-up device of the spinning machine, i. e., the spinning spool, an intermediate drawing roller or take-up godet, or to a centrifugal spinning pot or the like. I

The thread guide may be in the form of a roller which is either positively driven or which rotates freely as the thread passes thereover under the drawing power ,of an additional device that draws .off the thread. However, a stationary guide may how of liquid where the thread contacts the guide roller is of great advantage, due to a more perfect washing or rinsing of the said thread guide.

The upwardly extending mouth 9 of the funnel I as shown in Figure 1 is also effective in this respect. The upward inclination of the mouth 9 causes the liquid stream ejected from the funnel to flow slightly upwardly so that it is directed in the direction of the roller in where it exercises its favorable rinsing action.

Under certain circumstances, it may be preferable to arrange precipitating bath nozzles in an intermediate bottom mounted in the trough, as

shown in Figure 2 and to feed them from a precipitating bath room which is held under a constant pressure.

As shown in both forms of the invention, a

certain annular space or clearance is left between the mouth of the funnel and the sides of the spinning bath trough and arrangements may be provided whereby this clearance may be varied. For example, as illustrated in Figure 2 of the drawing, the bracket 24 may be adjustably mounted to slide in a sleeve 32 and held in position in said sleeve by a set screw 33.

The force of the precipitating bath stream flowing through the funnel depends largely upon the size of the funnel and the flowing power of the precipitating bath at the time when it emerges from the spin bath nozzles, and upon the size of the clearance existing between the end of the funnel facing the nozzle and the wall adjacent the nozzle. As brought out above, the proportion between the precipitating bath stream freshly introduced through the nozzles 6 and 28 and the precipitating bath already used, i. e., precipitating bath which flows from the trough through the annular clearance into the insertion, can be changed in any desired manner through adjustment of the clearance between the wall of the trough and the end of the funnel adjacent thereto.

Although only two embodiments of the invention have been described herein, it is apparent that many modifications thereof may be utilized and it is not intended to restrict the invention to the embodiment shown. For example, the funnels may be different shapes and means of mounting the funnels within the trough may be changed in any desired manner without departing from the spirit and scope of the invention. Also the positioning of the spinning nozzle may be altered, for instance, the spinning nozzle might be above the tubular member and the thread be drawn vertically downwardly or at some other suitable angle. In this event, the spinning nozzle might be positioned above the spin bath and the nozzles for precipitating liquid could extend into the spin bath adjacent or within the tubular member. Also, the insertion might be of other shapes suitable for conducting the precipitating liquid in contact with the thread. For example, it might be in the form of an open trough. Although reference has been made to the introduction of fresh precipitating liquid at the nozzles 6 and 28, it is apparent that this may include the use of a precipitating liquid which is being reused after filtered and otherwise purified.

The above improvement has been described with particular reference to the cuprammonium process for producing artificial filaments, but it is not intended to thereby restrict its use to that process, since it may also be used to advantage with other processes for producing filaments of artificial origin; for example, it may be used to advantage in the viscose process.

The terms used in describing the invention have been used in their descriptive sense and not as terms of limitation and it is intended that all equivalents thereof be included within the scope of the appended claims.

Having thus described the invention as required by the patent statutes what is claimed is:

1. An apparatus of the class described, comprising a spinning nozzle, a trough containing a precipitating solution in which said spinning nozzle is immersed, a tubular element substantially concentric with and surrounding said spinnerette, and adapted to have the extruded threads pass therethrough, said tubular member having one end adjacent one side of said trough,

means to vary the distance between the side of said trough and said end. of said tubular member, and means to force fresh precipitating liquid through said tubular member and in the direction of travel of the filaments passing therethrough.

2. A device for manufacturing filaments of artificial origin comprising a spinneret, a precipitating bath through which the thread from the spinneret is conducted, a tube-like insert arranged within the precipitating bath and substantially concentrically around the extruded thread and means for forcing precipitating liquid through said insertion.

3. A device as defined in claim 2 in which the means for forcing precipitating liquid through said insertion comprises a nozzle for introducing precipitating liquid positioned in the vicinity of the spinneret.

4. A device as defined in claim 2 in which the spinneret is arranged within the tube-like insertion.

5. A device as defined in claim 2 in which the insertion has a conical shape.

6. A device as defined in claim 2 in which the insertion has a conical shape, the diameter of the conical insertion decreasing in the direction of travel of the thread.

7. A device as defined in claim 2 in which the insertion has a conical shape which is enlarged in the direction of travel of the thread.

8. An apparatus for spinning filaments of artificial origin, comprising a spinning nozzle, a spinning bath, a conduit positioned in said spinning bath and arranged so that filaments extruded from said spinning nozzle will pass through it, a nozzle directed to force precipitating liquid through said conduit and to draw precipitating liquid from said spinning bath into said conduit.

9. An apparatus for spinning filaments of artificial origin, comprising a spinning nozzle, a spinning bath, a conduit positioned in said spinning bath and arranged so that filaments extruded from said spinning nozzle will pass through it, a nozzle directed to force precipitat ing liquid through said conduit and to draw precipitating liquid from said spinning bath into said conduit, and means for adjusting the area of the inlet for precipitating liquid into said conduit.

10. An apparatus of the class described, comprising a spinning nozzle from which a thread is extruded, a trough containing a precipitating solution in which said spinning nozzle i immersed, a conduit surrounding said spinning nozzle longitudinally and adapted to have the extruded thread pass therethrough, said conduit being substantially submerged insaid precipitating solution and having one end thereof adjacent one side of said trough, and means submerged in said precipitating solution for forcing fresh precipitating liquid through said conduit and in the direction of travel of the thread passing therethrough.

11. A device of the class described, comprising a spinnerette, a precipitating bath through which the thread from the spinnerette is conducted, a conduit arranged substantially within the precipitating bath and substantially concentrically around the extruded thread, means for forcing precipitating liquid through said conduit, said conduit having one end adjacent one side of said trough, and a take-up roller partly submerged in the precipitating solution and pivotally mounted adjacent the other end of said conduit and "adapted to receive the thread issuing from said conduit.

12. A device of the class described, comprising a spinnerette from which a thread is extruded,

through, an intermediate bottom in said trough positioned below said conduit, and means ar:-

ranged in said bottom for forcing fresh precipitating liquid through said conduit, said bottom .and said conduit forming a uniform and adjustable annular clearance adapted to control the amount of precipitating liquid passing from said trough'into said conduit.

WALTER OSTERMANN.

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