CN109790652B

CN109790652B - Method and device for cooling synthetic yarns

Info

Publication number: CN109790652B
Application number: CN201780058217.XA
Authority: CN
Inventors: P·容贝克; T·穆恩斯特曼
Original assignee: Oerlikon Textile GmbH and Co KG
Current assignee: Oerlikon Textile GmbH and Co KG
Priority date: 2016-09-28
Filing date: 2017-02-14
Publication date: 2021-11-30
Anticipated expiration: 2037-02-14
Also published as: TW201814095A; EP3519617A1; CN109790652A; TWI803429B; WO2018059743A1; TWI774665B; JP6991225B2; JP2019533095A; TW202321536A; EP3519617B1

Abstract

The invention relates to a method for cooling a synthetic thread in a texturing zone of a texturing machine. For this purpose, a cooling liquid is fed into a cooling bath of the cooling body, the cooling liquid being dispersed in the bottom of the cooling bath. The heated yarn is guided through the cooling bath in a contacting manner. In order to avoid an excess of cooling liquid at the end of the cooling, the cooling liquid is fed in a delivery quantity in the range of 0.05 ml/min to 5 ml/min depending on the yarn titer of the yarn via a metering opening in the bottom of the cooling bath, wherein the flow rate of the cooling liquid is generated by a controllable metering member.

Description

Method and device for cooling synthetic yarns

Technical Field

The invention relates to a method for cooling synthetic threads and to a device for carrying out the method.

Background

For finishing spun synthetic yarns, multifilament crimping processes have been used for decades, which are also referred to in the industry as so-called false-twist texturing. For this purpose, the pre-oriented yarns which have been produced in a preceding melt-spinning process are crimped in the texturing zone of a texturing machine. In this case, false twisting, which is opposite to the direction of the thread, is mechanically produced on the thread. The yarn in the twisted state is heated to a temperature in the range of 200 ℃. The plastic state of the yarn material obtained here leads to a distortion that is prominent in the individual filaments of the yarn. To fix the yarn structure, the yarn was then directly cooled to a temperature of about 80 ℃. The crimp in the yarn is then retained and has the desired finishing effect. The yarn cooling is preferably carried out by means of an air-cooled cooling collar, on the surface of which the yarn is guided in a contacting manner. However, a fundamental disadvantage of such cooling collars is that relatively long cooling sections are required to obtain adequate cooling of the yarn. Therefore, methods and devices are known from the prior art, in which the cooling of the thread takes place by means of a cooling liquid in order to be able to obtain cooling sections which are as short as possible.

A similar process and device is known, for example, from EP0403098a 2. In the case of the known method and the known device for cooling synthetic threads, a cooling body with a cooling groove is provided, which cooling body has a plurality of recessed pockets in the groove base of the cooling groove. The cooling tank is connected to a cooling liquid storage tank through a capillary tube so that the cooling liquid is continuously fed into the cooling tank. The heated yarn is guided in contact through a cooling bath and cooled by a cooling liquid. The yarn is then directed across a downstream cooling collar.

In the case of the known method and in the case of the known device, the cooling body forms a relatively short cooling section, wherein excess cooling liquid is intercepted at the end of the cooling body and returned to the tank. The recycling of the cooling liquid leads to significant additional complexity, considering that in conventional deformation machines several hundred deformation zones are operated side by side in parallel with each other.

In order to minimize the coolant residue in the yarn cooling, WO0138620a1 discloses a method for cooling a synthetic yarn in a texturing zone, in which method the coolant is fed to the yarn by means of a metering pump, wherein the metering pump is adjusted as a function of the monitored liquid application on the yarn. The liquid applied to the yarn is measured here by means of the electrical resistance on the yarn after cooling. Thus, although a relatively large amount of residual cooling liquid can be avoided, this involves the possibility of a state in which the yarn is insufficiently cooled by insufficient cooling liquid. The state directly causes deterioration of curl uniformity.

Disclosure of Invention

The object of the present invention is now to provide a comparable method and a cooling device for cooling a synthetic thread in the texturing zone of a texturing machine, by means of which method or by means of which device, respectively, a uniform cooling of the thread can be carried out without a significant surplus of cooling liquid.

Another object of the invention is to improve a method and a cooling device of the generic type for cooling synthetic threads in such a way that a plurality of threads can be cooled in parallel, in particular under the same conditions.

The invention is based on the idea that the amount of cooling liquid and the yarn quality must be correlated with each other in a specific manner in order to obtain, on the one hand, the desired cooling effect and, on the other hand, to minimize the remaining cooling liquid at the end of the cooling. It should be ensured here that the cooling liquid is reliably supplied to the yarn. The method according to the invention therefore provides that the coolant is fed in a delivery quantity in the range from 0.05 ml/min to 5 ml/min, depending on the yarn titer, via a metering opening in the bottom of the cooling bath. The desired cooling of the yarn can then be achieved depending on the yarn titer without a relatively large residual amount of cooling liquid occurring after cooling.

Since a relatively strong evaporation of the cooling liquid occurs in the initial contact between the cooling liquid and the heated yarn, the wetting of the yarn to be cooled takes place in the cooling section on the bottom of the cooling groove. According to an advantageous development of the invention, the yarn is guided for this purpose via a section length of the cooling section in the range of 100-300 mm. Uniform wetting and cooling of the yarn can then be achieved.

The method variant in which the cooling liquid is distributed in the cooling bath to a plurality of successive pockets in the bath bottom has proved particularly successful, wherein the threads are guided in a contacting manner over a plurality of webs formed between the pockets. The cooling effect on the yarn can then also be intensified, so that a relatively short cooling section can be achieved.

In order to maintain a defined yarn guidance and a uniform yarn contact in the cooling channel in the deformation zone, a variant of the method in which the yarn is guided by a plurality of yarn guides arranged upstream and downstream of the cooling channel is extremely advantageous, wherein the cooling channel has a groove base between the yarn guides that is curved in the direction of the yarn run. The angle at which the yarn is moved into the cooling channel and guided out of the cooling channel can then be set in a very precise and reproducible manner. No separate adjustment in the machine or in the deformation zone is required due to the thread guides.

In order to keep the environment as free as possible of steam, a development of the method according to the invention is specified in which the steam resulting from the wetting of the yarn is intercepted and sucked off at the cooling bath. Intercepting and venting steam is particularly advantageous in view of the side-by-side parallel processing of many yarns in the texturing machine.

The suction connection of the suction device can be particularly advantageously arranged at the lowest point of the cooling channel in the outlet region in order to remove unused residual cooling liquid in addition to steam.

In order to carry out the method, the cooling device according to the invention has a metering device for supplying the cooling liquid, wherein the metering device has a metering member for generating a coolant delivery quantity in the range from 0.05 ml/min to 5 ml/min. Such metering means are preferably realized by means of a metering pump which is capable of generating a continuous uniform feed of the flow of cooling liquid and of supplying the latter to the cooling bath.

The application of the cooling liquid to the yarn in the cooling bath is carried out over a certain cooling section. For this purpose, the cooling channels on the cooling body are realized in the form of a cooling channel having a length in the range of 100-300 mm.

For increased cooling, it is also provided that the cooling channel has a plurality of recessed pockets at the channel bottom, which are separated from one another by guide webs in the channel bottom.

The guide webs between the pockets on the groove bottom of the cooling groove can be realized here in the form of web widths of the same web width and/or web widths of dissimilar dimensions in order to achieve yarn guidance and yarn wetting in the cooling groove.

In order to be able to guide the thread in a reproducible manner by uniform contact in the groove base of the cooling groove, a development of the device according to the invention is particularly advantageous in which at least one upstream and one downstream thread guide element are assigned to the cooling groove and the cooling groove has a groove which is curved in the course of the thread.

In order to intercept and remove the vapor, an exemplary embodiment of the device according to the invention is specified in which the cooling body is assigned a suction device to the cooling bath. The suction device is preferably designed such that residual fluid of the cooling fluid, which is potentially formed in the region of the outlet, is discharged from the cooling bath together with the steam. Environmental influences on the deformation machine can thus be avoided.

Drawings

The method according to the invention for cooling a synthetic yarn in the texturing zone of a texturing machine will be explained in more detail below by means of several embodiments of the device according to the invention and with reference to the accompanying drawings, in which:

figure 1 schematically shows a view of a texturing zone of a texturing machine with an integrated cooling device for cooling the yarn according to the invention;

fig. 2 schematically shows an embodiment of the cooling device of fig. 1 for cooling a yarn according to the invention;

FIG. 3 schematically shows a cross-sectional view of the embodiment of FIG. 2;

FIG. 4 schematically shows a cross-sectional view of another embodiment of a cooling device of the present invention;

fig. 5 schematically shows a cross-sectional view of another embodiment of the cooling device of the invention.

Detailed Description

Fig. 1 schematically shows a view of a part of a texturing machine, in particular a texturing zone. For this purpose, the texturing machine has a supply position 4, at which the feed bobbin 2 with the yarn 3 is held. Yarn 3 has previously been made as a pre-oriented yarn/filament (POY) in a melt-spinning process. The supply position 4 is assigned a first conveying unit 1.1. The delivery unit 1.1 is formed in this embodiment by a godet unit which is wound several times. The first transport unit 1.1 forms a yarn inlet to a so-called texturing zone, which extends to the second transport unit 1.2. The second delivery unit 1.2 is likewise formed by a godet unit which is wound several times. The type of the transport units 1.1 and 1.2 is exemplary here. In principle, a so-called nip transport unit can also be used to guide the yarn, wherein the yarn is guided in the nip between the drive shaft and the contact pressure roller and/or the contact press belt.

The heating device 5, the cooling device 6, the false twisting device 7 are arranged in the yarn direction in a texturing zone, which extends between the transport units 1.1 and 1.2. The cooling device 6 is formed by the device of the invention and is shown separately in fig. 2 and 3.

The embodiment of the cooling device 6 according to the invention as shown in fig. 2 and 3 is schematically shown in fig. 2 in a longitudinal sectional view and in fig. 3 in a transverse sectional view. The following description applies to both figures unless a figure is explicitly mentioned therein.

The exemplary embodiment of the cooling device 6 according to the invention has an elongated cooling body 10. The cooling channel 11 extends on the top side of the cooling body 10. The cooling channel 11 extends up to the end face of the cooling body 10, wherein the cooling channel 11 is assigned an inlet thread guide 8 at the thread inlet 24 and an outlet thread guide 9 at the thread outlet 25. The cooling channel 11 has an arcuate channel bottom 17, the curvature of which is determined by the radius R. The cooling section 5 extending between the yarn inlet 24 and the yarn outlet 25 at the groove bottom 17 is determined by the section length L in fig. 2.

The metering opening 12 in the base 17 of the cooling bath 11 opens into the region of the yarn inlet 24. The metering orifice 12 communicates with the metering device 13 via a metering conduit 12.1 and a supply line 26. The metering device 13 in this embodiment has a metering member 14 connected to a container 20. The cooling fluid is held in a container 20. The metering member 14 is preferably realized in the form of a metering pump and is driven by a motor 15. The motor 15 is controlled by a control device 16 connected to a machine control unit (not shown here).

The groove base 17 in the part of the cooling groove 11 extending between the metering opening 12 and the yarn outlet 25 has a plurality of recessed pockets 18, the pockets in the groove base 17 being separated from one another by a plurality of guide webs 19.

As can be gathered in particular from the illustration in fig. 3, the groove recess 18 forms a depression in the groove bottom 17, in which a build-up of cooling liquid potentially forms. The threads 3 are guided in a contacting manner on the surface of the guide web 19.

As can be taken from the illustrations of fig. 2 and 3, the suction device 21 is arranged above the cooling bath 11. The suction device 21 has a suction hood 23 which extends over the entire length and width of the cooling channel 11 on the cooling body 10. The suction hood 23 is connected to the vacuum source 22 so that the steam generated by the cooling liquid in the cooling of the yarn can be intercepted and removed. The vacuum source 22, which can be realized in the form of a blower, can advantageously work with a plurality of adjacent suction hoods 23.

It is explicitly mentioned here that this is an embodiment of the cooling device of the invention in terms of construction. The suction device 21 can then also be arranged below the cooling bath in order to be able to receive and discharge the residual liquid in particular also at the yarn outlet.

As can be seen from the representation in fig. 1, the yarn is mechanically twisted by the false twisting device 7 in order to deform, so that the filaments of the yarn 3 are twisted. The twist is reversed in opposition to the yarn direction and is generally prevented by a so-called twist stop at the entrance to the deformation zone. Subsequently, the twisted yarn 3 is heated to a temperature of about 200 ℃ in the heating device 5. In order to cool the heated yarn for the crimp setting, the yarn 3 is supplied to the cooling device 6 via the input yarn guide 8. The metering member 13 for cooling the twisted yarn generates a predetermined delivery amount of the cooling liquid, which is continuously fed into the cooling tank 11 via the metering port 12. The delivery volume is set here in the range from 0.05 ml/min to 5 ml/min, so that on the one hand sufficient cooling of the yarn occurs and on the other hand no significant residual cooling liquid is produced on the yarn after leaving the cooling bath 11. The absorption of liquid for cooling is limited by the twisted state of the yarn 3, and thus the cooling groove is formed in a specific section length in the range of 100-300 mm depending on the yarn count.

In the embodiment using a polyester yarn having a 300 denier yarn count (denier), the yarn can be sufficiently cooled in a 225 mm cooling zone. Water is used as the cooling fluid, wherein a minimum amount of oil, such as 1%, can be added to the water, depending on the requirements. The amount of cooling liquid was about 4 ml/min.

It has been confirmed that the twisted yarn can be efficiently cooled with the amount of cooling liquid in the range of 5% to 15% by weight of the yarn. The residual liquid at the end of the cooling process can then be minimized. The method according to the invention and the device according to the invention are therefore distinguished in particular by the fact that the yarn is cooled sufficiently during the texturing process with a minimum consumption of cooling liquid. No complex interception and preparation of residual liquid is required.

Furthermore, the presetting of the yarn guide can be achieved by the yarn guides 8, 9 at the yarn inlet 24 and the yarn outlet 25 of the cooling device 6, so that the same reproducible yarn guide can be achieved in a plurality of parallel processing positions. In this respect, complex shaping tasks in the deformation machine and in the deformation zone can be dispensed with.

In the case of the exemplary embodiment shown in fig. 2, the groove bottoms 17 of the cooling grooves 11 in the heat sink 10 are designed with uniform pockets 18, so that the guide webs 19 between the pockets all have the same web width. In principle, however, the web widths of the guide webs 19 in the groove base 17 can also be realized in a manner of dissimilar lengths. For this purpose, fig. 4 shows an embodiment of the cooling device according to the invention in which the guide webs 19 are realized with dissimilar web widths. The embodiment according to fig. 4 is otherwise identical to the embodiment according to fig. 2, wherein the suction device 21 and the metering device 13 are not shown here. The guide webs 19 in the outlet region in the exemplary embodiment according to fig. 4 are realized in a significantly wider manner than in the remaining region of the cooling channel 11. The supply of the cooling liquid to the thread can be reinforced on the basis of the groove pockets 18 in the groove bottoms 17 of the cooling grooves 11, so that a relatively short cooling section and thus a short cooling groove 11 on the cooling body 10 can be achieved. However, the cooling channel 11 can also be realized without a pocket.

Fig. 5 shows an embodiment of the cooling device according to the invention, in which the cooling channel 11 does not have any recess 18 at the channel bottom 17. The suction device 21 and the metering device 13 are also not shown here. The thread 3 is guided in this case without interruption of contact on the groove bottom 17 of the cooling groove 11. The coolant supplied to the cooling bath 11 through the metering opening 12 is uniformly dispersed on the bath wall of the cooling bath 11 and evaporated or carried by the yarn up to the yarn outlet 25.

In the embodiment of the device according to the invention shown in fig. 5, the metering line 12.1 opens into the cooling bath 11 by an inclination in the direction of the yarn. The flow of the delivered cooling liquid presupposes that the yarn run has been aligned and contributes to the spreading in the cooling bath 11.

Claims

1. Method for cooling a synthetic thread in a texturing zone of a texturing machine, wherein a cooling liquid is fed into a cooling bath of a cooling body, wherein the cooling liquid is dispersed in the bottom of the cooling bath and the heated thread is guided through the cooling bath in a contacting manner, characterized in that the cooling liquid is fed in a delivery quantity in the range from 0.05 ml/min to 5 ml/min depending on the thread titer via a metering orifice in the bottom of the cooling bath.

2. The method of claim 1, wherein the yarn is guided in a cooling section on the groove bottom of the cooling groove over a section length in the range of 100 mm to 300 mm.

3. The method according to claim 1 or 2, characterized in that the cooling liquid in the cooling bath is distributed to successive pockets in the bath bottom, wherein the yarn is guided in contact over webs formed between the pockets.

4. The method according to claim 1, characterized in that the yarn is guided by means of a plurality of yarn guides, which are arranged upstream and downstream of the cooling channel, wherein the cooling channel has a channel bottom between these yarn guides, which groove bottom is curved in the direction of the yarn run.

5. The method of claim 1 wherein steam generated by the wetted yarn is intercepted and drawn at the cooling bath.

6. A cooling device for carrying out the method according to any one of claims 1 to 5, having a cooling body (10) with an elongated cooling channel (11) for guiding a yarn (3), wherein the cooling channel (11) is connected to a metering device (13) for supplying a cooling liquid by means of a metering opening (12) in the channel bottom (17), characterized in that the metering device (13) has a controllable metering means (14) for generating a delivery volume of the cooling liquid in the range from 0.05 ml/min to 5 ml/min.

7. A cooling device according to claim 6, characterized in that the cooling channel (11) on the cooling body (10) has a length (L) in the range of 100 to 300 mm.

8. A cooling device according to claim 6 or 7, characterized in that the cooling channel (11) has a plurality of recessed pockets (18) in the channel bottom (17), which pockets are each separated from one another by a guide web (19) in the channel bottom (17).

9. A cooling device according to claim 8, characterized in that the guide webs (19) between the groove recesses (18) on the groove bottom (17) are realized in the form of web widths of the same and/or dissimilar dimensions.

10. A cooling device according to claim 6 or 7, characterized in that at least one thread guide (8) is arranged upstream of the cooling channel (11), at least one thread guide (9) is arranged downstream of the cooling channel (11), and that the cooling channel (11) has a channel bottom (17) which is curved in the direction of the yarn run.

11. Cooling unit according to claim 6 or 7, characterized in that the cooling body (10) is associated with a suction device (21) for intercepting and removing steam on the cooling bath (11).