EP1146151B2 - Process and apparatus for spinning and crimping of a multifilament yarn - Google Patents

Abstract

In the production of texturized filaments, the bundle of melt spun thermoplastic filaments is divided into part-bundles before texturizing. The part-bundles are texturized separately, and then combined into a filament yarn. In the production of a melt-spun and texturized filament yarn, the part-bundles have an equal number of filaments. Each part-bundle is texturized under identical conditions. Each part-bundle passes through a texturizing jet, to be crammed into a plug. Each filament plug is drawn out separately into texturized part-bundles, to be combined into a yarn. The filament part-bundles are heated at the texturizing jets, and the filament plugs are cooled away from the jets. The part-bundles are processed between the cooling and the texturizing stages, and after texturizing before forming the yarn. The extruded melt-spun filament bundle is divided into two equal part-bundles during or after or before the initial cooling stage. The part-bundles are eddied together to form the filament yarn. An Independent claim is included for a filament melt spinning and texturizing assembly, where the extruded bundle (5) of melt-spun filaments is divided (6) into part-bundles (7.1,7.2) at the cooling shaft (4), before they reach the texturizing station (8). The texturizing station has two parallel texturizing units (9) to take the separate filament part-bundles. The texturized part-bundles are brought together (13) into a yarn (16) before winding (17) on a bobbin. Preferred Features: The filament bundle divider has guides (20.1,20.2) within the cooling shaft to form part-bundles of filaments, or they are between the cooling shaft and the texturizing station. The filament bundles can be divided by a jet assembly within the spinneret (1). The texturizing units have a guide channel (10.1,10.2) for each filament part-bundle, and a compression chamber (11.1,11.2) to form parallel filament plugs (12.1,12.2). A cooling drum can be after the texturizing jets, with a running track around the circumference for the texturized filaments drawn from each filament plug. The unit to combine the part-bundles into a yarn has an eddy chamber (14) to give an air stream through a yarn take-off channel (15).

Description

The invention relates to a method for spinning and crimping 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 10.

For producing a crimped yarn, it is known to extrude a filament bundle consisting of a plurality of strand-like filaments from a thermoplastic melt by means of a spinning device. The filament bundle is crimped after cooling by means of a crimping device. Here, the individual filaments of the filament bundle are deformed into loops and sheets, so that the thread formed from the filament bundle has a crimp. In order to achieve such a change in shape of the filaments of the filament bundle, the crimping device can be formed, for example, as a texturing nozzle, in which the filament bundle is dammed up by means of a conveying medium to form a yarn plug. Upon impact of the filament bundle on the yarn plug thus produce the desired loops and bows of individual filaments. In order to achieve the best possible crimping, the filament bundle is guided through a hot medium and at the same time heated, so that a plastic deformation in the individual filaments of the filament bundle can take place. After cooling the yarn plug this is transferred by peeling in a crimped yarn, which is then wound up on a spool.

The curling of the thread is in this case in its intensity and stability in this case by the change in shape of the individual filaments, i. when using a texturing, influenced by the plug formation and by the thermal treatment of the yarn plug. Thus, in addition to the temperature and the pressure of the conveyor and the residence time of the yarn plug during the thermal treatment parameters that significantly affect the crimping result.

For example, from the DE 196 13 177 a method and a device are known in which the filaments of the guided to a yarn plug filament bundle are guided before dissolution to the crimped thread through an extremely long cooling section. In this case, however, there is basically the problem that with a higher number of individual filaments within the filament bundle uniform treatment is not guaranteed both in the formation of loops and sheets and in the heating and cooling of all filaments of the filament bundle.

Accordingly, it is an object of the invention to provide a method and apparatus for spinning and crimping a multifilament yarn which enables the production of a high quality crimped yarn having stable and uniform crimping of the filaments.

According to the invention, this object is achieved in that the filament bundle is divided before crimping by a release agent into a plurality of sub-bundles, that each sub-bundle is crimped separately and that the sub-bundles are brought together after crimping to the thread according to claim 1.

Nor has the invention been made by the known methods and apparatus of the EP 0 861 931 and EP 0 784 109 since the known methods and devices relate exclusively to the production of a composite thread of several partial threads. Each of the threads is different in its polymer, its color and / or its treatment. Each partial thread is formed in each case from a filament bundle. Each bundle of filaments receives an individual treatment. In contrast, the inventive method and apparatus according to the invention are designed to produce a thread from a filament bundle of a monochrome polymer melt. In this case, the invention is characterized in particular by the fact that the crimped thread receives a high crimp, which is increased over conventional crimped threads by at least 10%. By dividing the filament bundle into several sub-bundles, the individual filaments are treated particularly intensively during crimping. The high crimping causes a particularly large bulk of the thread, which is particularly characteristic of yarns for the production of carpets.

In order to ensure a uniform treatment of all individual filaments of the filament bundle, the process variant according to claim 2 is preferably used. Here, the number of filaments of each sub-beam is substantially equal and each sub-beam is crimped under substantially the same conditions.

The development of the invention, in which a texturing nozzle is used for crimping, is characterized in particular by the fact that the residence time for the treatment of the yarn plug is substantially increased without reducing the spinning speed.

In particular, during cooling of the yarn plug can thus achieve an intensive cooling even with a short cooling section, which ensures a sufficiently low temperature of the individual filaments upon dissolution of the yarn plug. Thus, the loops and bows embossed in the individual filaments are retained even at very high take-off speeds.

In the production of the crimped thread, however, it is also possible to pre-treat the sub-bundles after cooling and before crimping at least in one step. The pretreatment can be carried out, for example, by a turbulence or a wrong rotation on the partial bundles. However, it is essential here that each partial bundle is pretreated under the same conditions.

Likewise, after crimping and prior to merging, the sub-bundles could receive at least one aftertreatment. Again, the aftertreatment is carried out under the same conditions, so that the filament strands of the crimped yarn have substantially the same properties.

The division of the filament bundle can be carried out both after the cooling of the filament bundle and before the cooling of the filament bundle. In the latter case, the separation of the filament bundle is achieved by a division within the spinneret.

In order to combine the individual filaments of the sub-bundles after the crimping to the crimped thread, it is proposed according to an advantageous development of the invention to merge the sub-bundles by a turbulence to the thread. For a high thread closure is achieved at the same time.

To carry out the method, a device according to the invention with the features of claim 10 is proposed. The division of the filament bundle is made in several sub-bundles by a release agent, which is arranged in the yarn path in front of the crimping device. The crimping device consists of several identical texturing agents, each sub-bundle being associated with one of the texturing agents. In order to merge the sub-bundles into the crimped thread, a bonding agent is provided between the crimping device and the winding device.

The release agent may be formed by a plurality of yarn guides, which are arranged within the cooling device or between the cooling device and the crimping device. However, it is also possible to form the release agent by a nozzle pitch, which is formed within the spinning device.

Texturing nozzles are preferably used as texturing means, in which the sub-bundle is guided via a delivery channel to a stuffer box in which the filaments are popped up to form a thread stopper. Due to the division of the filament bundle is achieved that due to the reduced number of individual filaments, a higher degree of loop and arches formation within the yarn plug can be achieved.

Since hot conveying media are preferably used in the texturing nozzle to form the yarn plug, the yarn plugs can be guided for cooling on the circumference of a cooling drum. Such cooling drums have a radial flow of cooling air, which penetrates the adjacent to the circumference of the cooling drum thread plug for cooling. This uniform and intensive cooling of all parallel to the circumference of the cooling drum thread stopper is achieved until reaching the dissolution point.

As a composite means, a swirling nozzle is preferably used, which leads the sub-bundles together in a thread channel, which is acted upon by an air jet such that the individual filaments of the sub-bundles engulf each other.

The invention is not limited to the individual treatment steps nor to the said treatment agents, since the division and the equal treatment during the crimping of the sub-bundles and the merging of all filaments into one thread are essential for the method.

The method according to the invention will be described in more detail below with reference to some embodiments of the device according to the invention, and further advantages will be mentioned.

Fig. 1

schematisch ein erstes Ausführungsbeispiel der erfindungsgemäßen Vorrichtung;

Fig. 2

schematisch ein weiteres Ausführungsbeispiel der erfindungsgemäßen Vorrichtung.

They show:

Fig. 1

schematically a first embodiment of the device according to the invention;

Fig. 2

schematically a further embodiment of the device according to the invention.

In Fig. 1 a first embodiment of a device according to the invention for carrying out the method according to the invention is shown schematically. The device has a spinning device 1, which is connected via a melt feed 2 to a melt generator, for example a pump or an extruder (not shown here). The spinning device 1 has on the underside at least one spinneret 3. The spinneret 3 has a plurality of nozzle bores through which the melt supplied to the spinning device 1 are extruded under pressure to a plurality of individual filaments of a filament bundle 5. Below the spinning device 1, a cooling device 4 is provided, through which the filament bundle 5 is guided, so that the emerging at approximately melt temperature filament strands are cooled. The cooling device 4 is shown here by way of example as a cross-flow blowing, in which a cooling air is blown substantially transversely to the filament bundle 5.

In the outlet region of the cooling device 4, a release agent 6 is arranged. The release agent 6 has two yarn guides 20.1 and 20.2, by which the filament bundle 5 is divided into two substantially equal part bundle 7.1 and 7.2.

Below the cooling device 4, a crimping device 8 is provided. The crimping device 8 has two texturing means, which is designed as a texturing nozzle 9 with two conveying channels 10.1 and 10.2 arranged parallel to one another and two compression chambers 11.1 and 11.2 formed parallel to one another. In the delivery channels 10.1 and 10.2, a pumped medium is introduced from the outside under pressure at high speed, so that acts on the respectively guided in the delivery channel 10 sub-bundle 7, a tensile force in the thread running direction. The compression chambers 11.1 and 11.2 are outside of the texturing 9 extended by concentric pipe sections 27.1 and 27.2 for guiding the yarn plugs 12.1 and 12.2.

The crimping device 8 is a composite 13 subordinate. The composite means 13 is formed in the embodiment as a swirling nozzle 14. The Verwirbelungsdüse 14 has a thread channel 15, in which the sub-beams 7.1 and 7.2 are performed together. In the thread channel 15, a compressed air jet is introduced substantially transversely to the thread running direction of the sub-bundle, so that takes place within the thread channel 15 an intensive turbulence of the individual filaments of the sub-beams 7.1 and 7.2. On the outlet side of the composite 13, the thread 16 formed by the sub-beams 7.1 and 7.2 is withdrawn from a take-up device 17. In the winding device 17, the crimped thread 16 is wound into a coil 18.

At the in Fig. 1 illustrated embodiment, a thermoplastic melt is supplied through the melt supply 2 of the spinning device 1. The melt consists of a polymer, for example of a polyester, a polyamide or a polypropylene. In this case, components may be added to the melt in order to produce a monochrome thread. The melt is extruded via the spinneret 3 under pressure to the filament bundle 5. After cooling in the cooling device 4, the filaments of the filament bundle 5 are divided by the separating means 6 into two substantially equal partial bundles 7.1 and 7.2. For this purpose, the sub-beams 7.1 and 7.2 are guided by the yarn guides 20.1 and 20.2. The sub-bundle 7.1 is fed into the drafting nozzle 9 via the conveying channel 10.1. Likewise, the sub-bundle is retracted 7.2 through the conveyor channel 10.2 in the Texutierdüse 9. Within the texturing nozzle 9, the sub-bundle 7.1 is dammed to the yarn plug 12.1 in the stuffer box 11.1. The sub-bundle 7.2 is dammed parallel to the yarn plug 12.2 in the stuffer box 11.2. Here, the introduced to the delivery channels 10.1 and 10.2 conveying medium, preferably compressed air, under the same conditions, in particular under the same pressure and the same temperature supplied, so that each of the sub-bundles is dammed under the same conditions to a yarn plug. When the yarn plugs 12.1 and 12.2 are formed, the individual filaments of the partial bundles 7.1 and 7.2 are deposited and compacted in loops and sheets. To intensify a crimp while the yarn plug 12.1 and 12.2 can be heated within the stuffer box 11.1 and 11.2. The yarn plugs 12.1 and 12.2 are dissolved at the end of the staggered through the pipe sections 27.1 and 27.2 compression chambers 11.1 and 11.2, wherein the sub-beams have 7.1 and 7.2 crimped individual filaments. The sub-beams 7.1 and 7.2 are brought together and swirled within the swirl nozzle 14 to a thread 16. The thread 16 is wound in the winding device 17 to the coil 18.

By the method according to the invention, a thread is produced whose individual filaments have a very uniform and intensive crimping. Such threads are characterized by a crimp, which are compared to known methods by 10 to 20% higher. The crimping of the filaments can be improved by pretreating the partial bundles 7.1 and 7.2 before crimping. For this purpose, in the embodiment shown Fig. 1 each preconditioning means 19.1 and 19.2 of the crimping device 8 upstream. The pre-treatment means 19.1 and 19.2 could, for example, be formed by a further swirling nozzle. It is essential here that the partial bundles 7.1 and 7.2 each receive the same pretreatment, so that the thread 16 likewise receives a uniform filament structure.

In Fig. 2 a further embodiment of the device according to the invention for carrying out the method according to the invention is shown. The components of the same function are provided with identical reference numerals.

The device has a spinning device 1, which is connected via a melt feed 2 with a melt generator. On the underside of the spinning device, a spinneret 3 and a release agent 6 are arranged. The release agent 6 is formed as a nozzle pitch 21 in the spinneret 3, through which a division of the filament bundle 5 is achieved. The spinneret 3 thus extrudes a plurality of filaments, which are extruded in equal parts in a sub-beam 7.1 and a sub-beam 7.2.

Below the spinning device, a cooling device 4 is provided, which is identical to the previous example. In that regard, reference is made to the previous embodiment. In the yarn path of the cooling device 4 a crimping device 8 is arranged downstream. The crimping device 8 has two texturing agents 9.1 and 9.2. The texturing means 9.1 and 9.2 are each designed as a separate texturing nozzle, each having a thread channel and a stuffer box. In this case, the sub-beams 7.1 and 7.2 are heated immediately prior to formation of the yarn plug. For this purpose, a hot medium could be used in the texturing 9.1 and 9.2. Both partial bundles 7.1 and 7.2 are heated to a substantially identical temperature. To cool the yarn plugs 12.1 and 12.2, the texturing means 9.1 and 9.2 are followed by a cooling drum 22. The cooling drum 22 has on the circumference two parallel running tracks 23.1 and 23.2. The tracks 23.1 and 23.2 are permeable to air, so that an air stream formed in the interior of the cooling drum 22 is guided radially outwardly through the thread plugs 12.1 and 12.2 guided in the tracks 23.1 and 23.2. Thus both yarn plugs 12.1 and 12.2 are cooled uniformly. To dissolve the yarn plugs 12.1 and 12.2, the partial bundles 7.1 and 7.2 are drawn off by a take-off means 24 and fed to a composite means 13. The withdrawal means 24 could be formed for example by a driven galette. Within the composite means 13, the partial bundles 7.1 and 7.2 are brought together to form the thread 16. The thread 16 is withdrawn by a conveyor 13 downstream of the conveyor means 25 and guided to the winding device 17. In the winding device 17, the crimped thread 16 is then wound into a coil 18.

At the in Fig. 2 As shown, the composite could also be formed as a swirl nozzle. It is particularly advantageous if the conveyor 25 leads the sub-beams 7.1 and 7.2 with flow to the composite means 13 in order to obtain an intensive mixing of the individual filaments of the sub-beams 7.1 and 7.2. To improve the mixing of the individual filaments within the thread 16, a further treatment of the thread in the form of a swirling could take place immediately before the winding. This is in Fig. 2 in the thread running direction immediately before the take-up device 17 a Verwirbelungsdüse 26 shown in dashed lines.

The in the FIGS. 1 and 2 illustrated embodiments for carrying out the method are exemplary in their arrangement and their choice of components. Thus, further pre-treatment or post-treatment steps may be introduced to obtain, for example, stretching or partial stretching of the sub-bundles or thread. Likewise, the shape changes of the filaments of the sub-beams can be generated by texturing in the form of twist or Zwirngebern. Likewise, the division of the filament bundles into two sub-bundles is exemplary. To intensify the crimping more than two sub-bundles can be parallel curled next to each other and then merged into a thread. It is essential here that the treatment of the partial bundles is carried out under the same conditions in order to obtain a thread having a uniform filament structure from a monochrome polymer melt.

LIST OF REFERENCE NUMBERS

1

spinner

2

melt feed

3

spinneret

4

cooling device

5

filament bundles

6

release agent

7

partial bundle

8th

crimping

9

Texturing nozzle, texturizer

10

delivery channel

11

stuffer

12

yarn plug

13

composite means

14

swirl jet

15

thread channel

16

thread

17

takeup

18

Kitchen sink

19

pretreatment agents

20

thread guides

21

nozzle pitch

22

cooling drum

23

running track

24

withdrawal means

25

funding

26

swirl jet

27

pipe section

Claims (15)

1. Method of spinning and crimping a multifilament yarn by way of spinning unit, the spinning unit having at least one spinneret on an underside, wherein a filament bundle consisting of a plurality of strandlike filaments is extruded through a spinneret from a single-colour thermoplastic melt, and wherein the filament bundle is cooled, crimped, and wound as a yarn to a package, characterized in that the filament bundle from one spinneret is divided into a plurality of partial bundles by a separating means before crimping, that each partial bundle is separately crimped, and that the partial bundles are combined to the yarn after crimping.
2. Method of claim 1, characterized in that the number of filaments of each partial bundle is substantially the same, and that each partial bundle is crimped under substantially identical conditions.
3. Method of claim 1 or 2, characterized in that for crimping each partial bundle is compressed by respectively one texturing nozzle to a yarn plug, that the yarn plugs are disentangled separately from one another to respectively one crimped partial bundle, and that the partial bundles are combined to the yarn after disentangling the yarn plugs.
4. Method of claim 3, characterized in that the partial bundles are heated within the texturing nozzle, and that the yarn plugs are cooled outside of the texturing nozzle.
5. Method of one of claims 1 to 4, characterized in that each of the partial bundles undergoes at least one pretreatment after being cooled and before being crimped.
6. Method of one of claims 1 to 5, characterized in that each of the partial bundles undergoes at least one aftertreatment after being crimped and before being combined.
7. Method of one of the foregoing claims, characterized in that after being cooled or while being cooled, the filament bundle is divided into at least two identical partial bundles.
8. Method of one of claims 1 to 6, characterized in that before being cooled, the filament bundle is divided into at least two identical partial bundles.
9. Method of one of claims 1 to 8, characterized in that the partial bundles are combined to the yarn by an entanglement.
10. Apparatus for carrying out the method of one of claims 1 to 9, with a spinning unit (1) which has at least one spinneret (3) on an underside, wherein a filament bundle (5) consisting of a plurality of strandlike filaments can be spun by a spinneret (3), with a cooling device (4) for cooling the filaments, with a crimping unit (8) for crimping the filaments, and with a takeup unit (17) for winding a yarn (16) to a package (18), characterized in that a separating means (6) is provided in the yarn path upstream of the crimping unit (8) for dividing the filament bundle (5) from one spinneret (3) into a plurality of partial bundles (7.1, 7.2), that the crimping unit (8) includes a plurality of texturing means (9) arranged parallel to one another in side-by-side relationship, wherein one of the texturing means (9) is associated with each partial bundle (7), and that between the crimping unit (8) and the takeup unit (17) a combining means (13) is arranged for joining the partial bundles (7.1, 7.2).
11. Apparatus of claim 10, characterized in that the separating means (6) is formed by a plurality of yarn guides (20.1, 20.2), which are arranged inside the cooling device (4) or between the cooling device (4) and the crimping unit (8).
12. Apparatus of claim 10, characterized in that the separating means (6) is formed by a spinneret partition (21), which is formed inside the spinning unit (1).
13. Apparatus of one of claims 10 to 12, characterized in that the texturing means (9) are designed and constructed as at least one texturing nozzle with a conveying channel (10) for each partial bundle and a stuffer box (11) for each partial bundle, the stuffer boxes (11) being arranged parallel to one another in side-by-side relationship for producing a plurality of yarn plugs.
14. Apparatus of claim 13, characterized in that downstream of the texturing nozzles (9.1, 9.2) a cooling drum (22) is arranged, which includes for each yarn plug (12.1, 12.2) a guide track (23.1, 23.2) formed on its circumference.
15. Apparatus of one of claims 10 to 14, characterized in that the combining means (13) is designed and constructed as an entanglement nozzle (14), which guides the partial bundles (7.1, 7.2) together in a yarn channel (15), to which an air jet is supplied.

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