WO2008128863A1

WO2008128863A1 - Method and device for twisting a multifilament thread

Info

Publication number: WO2008128863A1
Application number: PCT/EP2008/053967
Authority: WO
Inventors: Michael SCHRÖTER; Helmut Weigend
Original assignee: Oerlikon Textile Gmbh & Co. Kg
Priority date: 2007-04-19
Filing date: 2008-04-02
Publication date: 2008-10-30
Also published as: DE112008000419A5

Abstract

The invention relates to a method and a device for twisting a multifilament thread, wherein a free thread section is formed in a blowing chamber on the running thread by two neighboring support points. A stream of compressed air is applied to the free thread section of the thread in the blowing chamber. In order to enable even and low-friction twisting of the thread, according to the invention the support points for guiding the thread section are moved together in the direction of the thread run. The support means for guiding the thread are designed in a way such that they can be moved in order to interact with a nozzle device in a blowing chamber for creating a compressed air stream.

Description

Method and device for swirling a multifilament yarn

The invention relates to a method for swirling a multifilament yarn according to the preamble of claim 1 and to an apparatus for carrying out the method according to the preamble of claim 9.

In the production of multifilament yarns, it is known that the individual filaments of the multifilament yarns are mixed together by a stream of compressed air within the yarn. Such swirling of the filaments of the thread are used depending on the process and production for different purposes. Thus, for example, by a higher pressure when generating the compressed air flow within the thread to produce interlacings, which are known for example as Tangelknoten and lead to an improved thread closure of the filaments within the thread. However, it is also possible to carry out the swirling of the thread such that only a mixing of the filaments without knotting occurs. Such turbulence is used, for example, to even out a preparation application in the thread. Regardless of the nature and intended use of the swirling, the swirling of the thread is always carried out on a running thread guided in a process with a predetermined thread speed. For this purpose, the turbulences are preferably carried out periodically and thus at high frequency recurring on the thread.

Thus, for example, from DE 41 40 469 A1 a method and a device are known, in which a running thread is continuously guided through a blowing chamber, in which a pulse-like compressed air flow acts. The compressed air flow is generated here by a plurality of nozzle bores, which are formed in rows on the circumference of a roll shell. Within the roller, a compressed air connection is provided, each with the blowing chamber associated nozzle bore is connected. In that regard, a compressed air flow is generated in response to the rotation of the roll shell through each of the blowing chamber passing nozzle bore, which acts on the guided in the blowing chamber thread.

To swirl the thread is essential that prevails in the blast space a free piece of thread that ensures the required freedom of movement of the filaments. For this purpose, the thread is guided by support means, so that the free thread piece between the support points of the support means is formed and thus can be freely swirled within the blowing chamber by the compressed air flow.

However, such support means, which may be formed for example by conventional yarn guides, however, cause friction in each support point on the yarn is generated. Such yarn friction, which are exacerbated by the unilateral loading of the yarn by means of the compressed air during the swirling, however, are undesirable in many processes. Especially with multifilament yarns with a low yarn denier, such yarn friction can already lead to filament breaks.

It is therefore an object of the invention to provide a method and a device for swirling a multifilament yarn of the generic type, in which the yarn is vortexbar possible friction.

Another object of the invention is to realize the highest possible uniform turbulence of the yarn, for example, even at yarn speeds above 3,000 m / min, to produce a high degree of entanglement or a high number of knots within the thread. The object of the invention is achieved by a method having the features of claim 1 and by a device having the features of claim 9.

Advantageous developments of the invention are defined by the features and feature combinations of the respective subclaims.

The invention is detached from the previously customary concepts, in which the thread is drawn to the swirling by stationary held yarn guide, which form between them the used for swirling free thread piece. In contrast, the invention is based on a dynamic thread guide, in which the free thread piece forming support points are moved in the direction of yarn travel. This allows relative speeds between the thread and the support point to be minimized or completely avoided. In the event that the support points for guiding the thread piece are moved together at the same speed in the thread running direction, no relative speeds occur between the thread and the support points, so that the frictional forces acting in the thread are minimized due to the thread guide. In that regard, in the invention, the free thread piece formed between two adjacent support points as a whole is supplied to the nozzle means to swirl the multifilament yarn.

Surprisingly, it has been found that in the generation of periodic entanglements in the thread, the length of the free piece of thread between the pieces of thread is arbitrary. Thus, the entanglements introduced per unit length in the thread essentially depend on the air flow. In that regard, the development of the invention is particularly preferred in which the support points are held on the circumference of a rotatable guide roller, wherein the thread is guided with a partial looping on the circumference of the guide roller and wherein the compressed air flow is directed from the outside to the periphery of the guide roller. This allows a continuous turbulence of the open thread in realize a simple way. The adjacent support points can be used with identical speeds to guide the thread piece.

To guide the compressed air flow directed at the yarn, the intermediate space between the support points on the circumference of the guide roller is preferably used as a blowing space, wherein the blowing space is formed by a depression on the circumference of the guide roller. This allows the desired air ducts and turbulence effects to be achieved, depending on the shape and shape of the recess.

In order to achieve the highest possible turbulence on the thread, according to an advantageous development of the invention, a plurality of support points and intermediate recesses are formed on the guide roller, which are looped around by the thread. Thus, the free pieces of thread on the current thread can be formed directly one behind the other and vortex. The thus formed free thread pieces on the circumference of the guide roller can then be successively fed to the compressed air flow and swirl. The juxtaposition of the support points and the associated juxtaposition of pieces of thread leads to a high uniformity of each individual Verwir- belung on the thread. In particular, in the production of intertwining nodes, even at the highest thread speeds, a high number of vertebrae nodes per unit length can be produced in the thread.

To generate the compressed air flow, a stationary nozzle device is preferably used, which is assigned to the circumference of the guide roller in the wrap of the thread with a small distance.

The compressed air flow can be generated preferably pulsed, so that each free thread piece on the circumference of the guide roller is assigned a respective compressed air pulse. This advantageously makes it possible to produce an interlacing knot per free piece of thread on the thread. Thus, the distances and the number of entangling nodes in the thread can be determined by the shape of the guide roller and

- A - in particular, the support points formed on the guide rollers can be determined.

In a particularly advantageous variant of the method, the compressed-air flow is generated by a mating roll having a plurality of nozzle openings distributed around the circumference, the nozzle openings of the mating roll interacting with the depressions in a common nip, and the nozzle openings of the mating roll being connected to the compressed air in the nip get connected. This allows the coincidence of the thread pieces and the compressed air flow in a simple manner in a nip. As a result of a synchronous drive of the guide roller and the counter roller, the conditions for swirling the thread remain constant even at different yarn speeds.

The device according to the invention has for carrying out the method according to the invention on movable support means which form the support points for forming the free piece of thread. The support means are moved together in the direction of yarn travel. In order to avoid slip phenomena between the support points and the thread, the movement of the support means is adapted to the thread speed of the running thread.

To guide the thread, the support means are preferably held on the circumference of a rotatable guide roller, so that adjust the respective free thread pieces to swirl between the support means in a partial looping of the thread on the guide roller.

The blow chamber formed for receiving the compressed air flow is preferably formed by a depression on the circumference of the guide roller between the support means. Thus, the thread piece can be guided above the recess, wherein the compressed air flow generated by the nozzle opening is blown from the outside to the rollers and thus into the recess. The support means on the circumference of the guide roller are preferably formed according to an advantageous development of the invention by a plurality of guide webs, which are separated from each other to form the recess by grooves on the circumference of the guide roller and lead the thread in the wrap around the circumference of the guide roller. This safe thread guides during swirling are possible.

In order to produce a compressed air stream directed onto the circumference of the guide roller, the nozzle device is preferably arranged at a short distance in a stationary manner next to the guide roller.

To generate pulse-like compressed air streams, which in each case generate a stream of compressed air on a free piece of thread, the device according to the invention is preferably carried out in the variant in which the nozzle device is formed by a second rotatable counter-roller which has a plurality of nozzle openings distributed over the circumference. The nozzle openings formed on the circumference of the counter-roller coincide in each case with a recess of the opposite guide roller in the nip, wherein the guided in the nip nozzle openings in the interior of the counter-roller cooperates with a compressed-air connection.

In order to generate a compressed air pulse independently of the yarn speed per free piece of thread, the rollers are preferably driven synchronously.

The advantageous development of the device according to the invention, in which the guide roller has a plurality of circumferentially extending thread guide regions for guiding a plurality of parallel running threads, is preferably suitable for simultaneously winding a plurality of threads running parallel to one another. In this case, as the Verwirbelungsnuten in the guide sheath of Guide roller introduced depressions preferably form obliquely in the axial direction, so that the force applied to the guide roller compressed air pulses in the individual guide areas occur with a time delay.

The method according to the invention and the device according to the invention are thus particularly suitable for producing a uniform turbulence, in particular a high number of turbulence nodes in a running thread. By erfmdungsgemäße leadership of the thread piece friction effects between the thread and the support means can be advantageously avoided, so that even delicate and fine thread titer can be vortexed with high uniformity.

The invention will be explained in more detail with reference to some embodiments of the device according to the invention for carrying out the method according to the invention with reference to the accompanying figures.

They show:

Fig. 1 shows schematically a first embodiment of the device according to the invention for carrying out the method according to the invention

2 schematically shows a cross-sectional view of a further embodiment of the device according to the invention. FIG. 3 shows a schematic plan view of a further embodiment of the device according to the invention

In Fig. 1 is a cross-sectional view of a first embodiment of a device according to the invention for carrying out the method according to the invention is shown schematically.

The embodiment consists of a guide device 2 and a nozzle device 3, which cooperate to a thread treatment. The leadership Device 2 is formed by a rotatably mounted guide roller 4, which is driven by a drive, not shown here in the arrow direction. At the periphery of the guide roller 4 more support means 5 are arranged at a uniform distance from each other. The support means 5 protrude with a guide end and each form a support point at its free end. Between two adjacent support means 5 a recess 6 is formed in each case as a free space.

To guide a thread 1, the thread 1 is guided with a partial looping around the circumference of the guide roller 4 over the free ends of the support means 5. Here, each free thread pieces 8 form between the support points of the support means 5.

In the wrap-around region of the guide roller 4, a nozzle device 3 is held stationary at a short distance from the free ends of the support means 5. The

Nozzle device 3 has a nozzle block 13, which has an extension oriented in the radial direction of the guide roller 4, which extends at least over the length of a thread piece 8. In the middle area of the nozzle block

13, a nozzle opening 9 is formed, which opens into a blast space 7 between the guide roller 4 and the nozzle block 13. The blowing chamber 7 is in each case formed by the depression 6 between two support means 5.

The nozzle opening 9 is associated with a blocking means 12 which connects the nozzle opening 9 optionally with a pressure line 14. The pressure line 14 leads to a compressed air source, which is not shown here. The blocking means 12 is coupled to a control means 10 for control. The control means 10 is connected to a sensor means 11 which senses the support means 5 on the circumference of the guide roller 4.

For swirling the multifilament yarn 1, for example, in a spinning process or a further processing process by a plurality of fine filaments is formed, the thread 1 is guided on the circumference of the guide roller 4 via the support means 5 with Teilumschlingung. The peripheral speed of the guide roller 4 is chosen such that substantially no relative movements between the support means 5 and the thread 1 occur. In that regard, see between the support points of the support means 5, the free thread pieces 8 on the thread 1 from. With progressive movement of the guide roller 4, the free thread pieces 8 are guided to the nozzle device 3. By means of the sensor means 11 on the nozzle device 3, the support means 5 are sensed on the circumference of the guide roller 4, so that via the control means 10 a compressed air pulse via the blocking means 12 is triggered when the recess 6 at the periphery of the guide roller 4 at the level of the nozzle opening. 9 lies. The tensioned between the support means 5 thread piece 8 is swirled by the compressed air flow within the blast chamber 7.

With progressive movement of the guide roller 4, the next piece of thread 8 is now guided into the blowing chamber 7 and swirled. In the meantime, the blocking means 12 is closed in the nozzle device 3, so that a next compressed air flow is triggered only when passing the next support means 5.

The exemplary embodiment illustrated in FIG. 1 is particularly suitable for this purpose in order to produce one entanglement node per thread piece in the thread 1. The size of the guide roller 4 and the number of support means 5 and the length of the thread pieces 8 between the support means 5 can be selected depending on the desired process and depending on the desired knotting per unit length in the thread 1.

However, the embodiment of FIG. 1 could also be combined with a nozzle device 3, in which from the nozzle opening 9, a permanent compressed air flow is generated. In this case, vortexing without knotting would preferably be created. For this purpose, the blocking means 12, the sensor means 11 and the control means 10 would not be present. The nozzle device 3 would thus from the nozzle block 13, the Düsenöffhung 9 and connected to the Düsenöffhung 9 pressure line 14 consist.

FIG. 2 schematically shows a further exemplary embodiment of the device according to the invention for carrying out the method according to the invention in a cross-sectional view. In the embodiment shown in FIG. 2, the guide device 2 is formed by a guide roller 4 and the nozzle device 3 by a counter-roller 17, which face each other in a nip 28. The guide roller 4 has on its circumference a plurality of groove-shaped depressions 6, which are formed uniformly distributed over the circumference and form guiding webs 15 between them. The guide webs 15 are in this case the support means 5 for guiding the thread. The swirling grooves 16 form the respective depressions 6 between the support means 5. The guide roller 4 is driven in the direction of the arrow, the circumferential speed preferably being identical to the thread speed of the thread 1 is selected. The thread 1 wraps around the guide roller 4 with a wrap angle of preferably> 45 °. In the wrap-around area, the free thread pieces 8 of the thread 1 form on the circumference of the guide roller 4 in each case between the guide webs 15.

The nozzle device 3 has a counter-roller 17, which is formed as a hollow cylinder. The counter-roller 17 has a plurality of nozzle openings 9, which penetrate the counter-roller 17 completely radially. The number of nozzle openings 9 in the counter-roller 17 is identical to the number of swirling grooves 16 on the circumference of the guide roller 4.

In the interior of the counter roll 17, a Druckluftstator 18 is arranged, which has an internal compressed air chamber 19, which is connected via a pressure line 14 to a compressed air source, not shown here. The compressed air chamber 19 in the interior of the Druckluftstators 18 is connected via a compressed air passage 20 at the level of the nip 28 with the nozzle openings contained in the counter-roller 17 9 connected. Here, a seal 21 is provided between the counter roll 17 and the compressed air stator 18 gap. The compressed air present in the compressed air duct 20 is in each case only temporarily taken up alternately by the individual nozzle openings 9 guided into the nip 208 and blown into the blowing chamber 7 formed in the nip 28. The blowing chamber 7 is limited by the Verwirbelungsnuten 16 on the circumference of the guide roller 4.

The counter-roller 17 is driven synchronously with the guide roller 4 in the direction of the arrow, so that in each case a Verwirbelungsnut 16 of the guide roller 4 and a nozzle opening 9 in the counter-roller 17 meet and lead to the Verwir- belung a thread piece 8, which above the blowing chamber. 7 is guided between the guide webs 15. When a Verwirbelungsnut 16 of the guide roller coincides with a nozzle opening 9 of the counter roll 17, a compressed air flow is generated by the compressed air from the compressed air channel 20 flows into the nozzle opening 9. The compressed air flow opens at the end of the nozzle opening 9 in the limited by the Verwirbelungsnut 16 and formed by the recess 6 Blasraum 7. Therefore, the thread piece 8 of the thread 1 is swirled.

The exemplary embodiment of the device according to the invention for carrying out the method according to the invention shown in FIG. 2 can advantageously also be extended in such a way that a plurality of threads can be simultaneously vortexed in parallel. For this purpose, a further embodiment of the device according to the invention is shown in Fig. 3, which substantially corresponds in its cross-sectional view of the embodiment of FIG. 2. In that regard, reference is made to the preceding description.

In the embodiment shown in Fig. 3, a plurality of yarn guide portions 22 are provided on the guide roller 4, so that at the periphery of the guide roller 4 at the same time a plurality of threads are guided with Teilumschlingung can. In the exemplary embodiment according to FIG. 3, three threads 1 are shown by way of example. The Verwirbelungsnuten 16 on the circumference of the guide roller 4 are formed obliquely in the axial direction with an inclination angle to the axis, wherein the cooperating with the Verwirbelungsnuten 16 nozzle opening 9 of the backing roll 17 are also arranged offset from one another. Assuming that the compressed air supplied by the compressed-air stator 18 is identical to the exemplary embodiment shown in FIG. 2, the generation of the compressed-air flow and thus the swirl generated is due to the staggered arrangement of the nozzle openings 9 and the oblique course of the swirling grooves 16 occur at the adjacent threads in a staggered sequence.

The guide roller 4 is driven via the drive shaft 23 and the roller motor 24. The counter-roller 17 is associated with a gear means 25 and a gear motor 26 through which the counter-roller 17 is driven. The gear motor 26 and the roller motor 24 are controlled by a common control device 27 such that the guide roller 4 and the counter roller 17 are driven synchronously. Thus, meet the nozzle openings 9 in the counter-roller 17 always with the Verwirbelungsnuten 16 of the guide roller 4 together.

LIST OF REFERENCE NUMBERS

1 thread

2 guide device

3 nozzle device

4 guide roller

5 proppant

6 deepening

7 blowing room

8 thread piece

9 nozzle opening

10 control means

11 sensor means

12 blocking means

13 nozzle block

14 pressure line

15 guide bar

16 swirl groove

17 mating roll

18 compressed air stator

19 compressed air chamber

20 compressed air duct

21 seal

22 thread guide area

23 drive shaft

24 roller motor

25 gear means

26 geared motor

27 control device

28 nip

Claims

claims

Anspruch [en] A process for swirling a multifilament yarn, in which a free piece of thread is formed in a blowing chamber on the running yarn through two adjacent support points and in which a compressed air flow in the blowing space acts on the free yarn piece of the yarn, characterized in that Support points for guiding the thread piece are moved together in the thread running direction.

2. The method according to claim 1, characterized in that the support points are held on the circumference of a rotatable guide roller, wherein the thread is guided with a partial loops on the circumference of the guide roller and wherein the compressed air flow from the outside to the

Scope of the guide roller is directed.

3. The method according to claim 2, characterized in that the free thread piece on the circumference of the guide roller above a

Blasraum forming depression is guided on the circumference of the guide roller, in which recess the compressed air flow is blown from the outside.

4. The method according to any one of claims 2 or 3, characterized in that the thread on the circumference of the guide roller wraps around a plurality of support points and recesses lying therebetween and that the thus formed free pieces of thread on the circumference of the roller are successively supplied to the compressed air flow.

5. The method according to claim 3 or 4, characterized in that the compressed air flow is generated by a stationary nozzle device which is associated with the circumference of the guide roller in the wrap of the thread with a small distance.

6. The method according to claim 5, characterized in that the compressed air flow is generated like a pulse, wherein the compressed air pulse is directed in each case to the free thread piece on the circumference of the guide roller.

7. The method according to claim 6, characterized in that the compressed air flow is generated by a counter-roller having a circumferentially distributed plurality of nozzle openings, wherein the nozzle openings of the counter-roller cooperate with the recesses of the guide roller in a common nip and wherein the nozzle opening of the counter-roller at the transition into the nip with a compressed air connection.

8. The method according to claim 7, characterized in that the guide roller and the counter roller are synchronously driven so that one of the recesses coincide with one of the nozzle openings in the nip.

9. Device for swirling a multifilament yarn (1) with two mutually spaced support means (5) for guiding the yarn (1), with a between the support means (5) formed blowing chamber (7) and with a nozzle device (2) Generation of a compressed air stream, wherein the thread (1) between the support means (5) forms a free thread piece (8) on which the compressed air flow within the blast space (7) acts, characterized in that the support means (5) are designed to be movable and to guide the thread piece ( 8) are movable together in the direction of yarn travel.

10. The device according to claim 9, characterized in that the support means (5) are held on the circumference of a rotatable guide roller (4) and that the nozzle device (3) with a nozzle opening (9) from the outside of the circumference of the guide roller (4) is associated , wherein the thread (1) can be guided with a partial looping around the circumference of the guide roller (4).

11. The device according to claim 9 or 10, characterized in that the blowing chamber (7) between the support means (5) by a recess (6) on the circumference of the guide roller (4) is formed, wherein the thread piece (8) above the recess (6) is formed and wherein the compressed air flow generated by the nozzle opening (9) in the recess (6) is inflatable.

12. The device according to claim 11, characterized in that on the circumference of the guide roller (4) the support means (5) by a plurality of guide webs (15) are formed, which for forming the recesses (6) by grooves (16) on Scope of the guide roller (4) are separated from each other and in the wrap around the circumference of the guide roller (4) guide the thread (1).

13. The device according to one of claims 10 to 12, characterized in that the nozzle device (3) with the Düsenöffhung (9) is arranged at a short distance fixed adjacent to the guide roller (4).

14. The device according to one of claims 10 to 12, characterized in that the nozzle device (3) by a second rotatable counter-roller (17) is formed, which has distributed over the circumference a plurality of nozzle openings (9), and that the nozzle openings (9) on Circumference of the mating roll (17) in a nip (28) formed between the two rolls (4, 17) each with one of the depressions (6) of the opposite guide roll (4) and a compressed air channel (20) formed in the interior of the mating roll (17) interacts.

15. The apparatus according to claim 14, characterized in that both rollers (4, 17) are driven synchronously in such a way that one of the recesses (6) with one of the nozzle openings (9) in the nip (28) coincide.

16. The apparatus according to claim 13, characterized in that the guide roller (4) on the circumference a plurality of radially encircling Fadenfüh- approximately areas (22) for guiding a plurality of parallel running threads (1), each thread (1) in the thread guide region (22). at least one thread piece (8) guided between support means (5) and wherein one of a plurality of nozzle openings (9) of one or more nozzle devices (3) is assigned to each thread guide region (22).