TW202321536A - Method and device for cooling a synthetic yarn - Google Patents

Abstract

The invention relates to a method and to a cooling device for cooling a synthetic yarn within a texturizing zone of a texturizing machine. To this end, a cooling liquid is introduced into a cooling groove of a cooling body, said cooling liquid being distributed in the groove base of the cooling groove. The heated yarn is guided in a contacting manner through the cooling groove. In order for an excess of cooling liquid to be avoided at the end of cooling, the cooling liquid, depending on a yarn count of the yarn, is supplied through a metering opening in the groove base of the cooling grove at a conveying rate in the range from 0.05 ml/min to 5 ml/min, wherein the conveying rate of cooling liquid is generated by a controllable metering means.

Description

Method and cooling device for cooling synthetic yarn

The present invention relates to a method for cooling synthetic yarns according to the preamble of claim 1 and to a cooling device for carrying out the method according to the preamble of claim 8 .

For processing spun synthetic yarns, a method for crimping multifilament yarns, also known in the industry as so-called false-twist texturizing, has been used for decades. For this purpose, partially oriented yarns which have previously been produced by the melt-spinning process are crimped in the texturizing zone of the weaving machine. Here, a false twist is mechanically produced on the yarn, which recurs counter to the yarn running direction. The yarn in this twisted state is heated to a temperature in the range of 200°C. The plastic state obtained here by the yarn material results in the twist being pressed into the individual filaments of the yarn. In order to set the yarn structure, the yarn is then immediately cooled to a temperature of about 80°C. In this way, the crimp remains in the yarn, and the desired processing is achieved. The cooling of the yarn here is preferably carried out by means of an air-cooled cooling track which guides the yarn in contact on its surface. However, this type of cooling track basically has the disadvantage that relatively long cooling sections are required in order to achieve proper cooling of the yarn. Therefore, with regard to the cooling of the yarn with a cooling liquid, several methods and devices are known from the prior art in order to be able to achieve the shortest possible cooling sections.

A generic method and a generic device are known, for example, from European Patent No. EP 0 403 098 A2. With regard to the known method and the known device for cooling synthetic yarns, the cooling body is provided with cooling grooves with depressed groove pockets at the bottom of the grooves. The cooling tank is coupled to a cooling liquid reservoir with a capillary tube to continuously introduce cooling liquid into the cooling tank. The hot yarn is guided in contact through cooling slots and cooled with a cooling liquid. The yarn is then guided over a downstream cooling track.

With known methods and known devices, the cooling body forms a relatively short cooling section in which excess cooling liquid at the end of the cooling body is collected and returned to the water tank. Considering that hundreds of weaving zones are operated side by side in parallel in conventional weaving machines, the recovery of the cooling liquid leads to a significant additional complexity.

In order to minimize the excess of cooling liquid during cooling of the yarn, a method for cooling synthetic yarns in the weaving zone is known from World Patent No. WO 0138620 A1, wherein the cooling liquid is supplied to the yarn with a metering pump, wherein, The adjustment of the metering pump depends on the application of the monitored liquid on the yarn. The application of the liquid to the yarn is measured on a portion of the yarn by electrical resistance after cooling. Although a relatively large excess of cooling liquid can indeed be avoided, a disadvantage is that insufficient cooling of the yarn may occur due to insufficient cooling liquid. These states directly lead to deterioration of crimp uniformity.

At this point, the object of the present invention is to provide a generic method and a generic cooling device for cooling synthetic yarns in the weaving zone of a weaving machine, by means of which method and device, respectively, a uniform cooling of the yarn can be achieved without Any substantial excess cooling liquid.

Another object of the present invention is to improve the generic method and the generic cooling device for cooling synthetic yarns in this way, in particular enabling parallel cooling of a plurality of yarns under the same conditions.

This object is achieved with a method for cooling synthetic yarns, as described in the preamble of claim 1, and a cooling device for carrying out the method, as described in the preamble of claim 6.

Advantageous refinements of the invention are defined by the features and combinations of features of the individual dependent items.

The invention is based on the concept that there must be a specific correlation between the quantity of cooling liquid and the quality of the yarn in order to obtain the desired cooling effect on the one hand and to minimize any excess of cooling liquid at the end of cooling on the other hand. Here it is ensured that the cooling liquid is supplied to the yarn in a reliable manner. The method of the invention thus provides, depending on the yarn count of the yarn, supplying the cooling liquid to the tank of the cooling tank through a metering opening at a delivery rate of between 0.05 ml/min and 5 ml/min. Bottom. Depending on the yarn count of the yarn, the desired cooling can thus be achieved without any relatively large excess cooling liquid occurring after cooling.

Due to the relatively intensive evaporation of the cooling liquid after the first contact of the cooling liquid with the hot yarn, the wetting of the yarn to be cooled takes place in the cooling section on the bottom of the cooling groove. For this purpose, according to an advantageous development of the invention, the yarn is guided over a cooling section with a section length between 100 mm and 300 mm. Homogeneous wetting and cooling of the yarn is thus possible.

Here is a method variant concerning the distribution of the cooling liquid in the cooling tank over successive pockets in the bottom of the tank, wherein the yarn is guided in contact over the plurality of pockets arranged between the pockets. web, which has proven particularly successful. Thus, the cooling effect on the yarn can even be enhanced so that relatively short cooling sections can be implemented.

In order to maintain a given yarn guidance and at the same time uniform contact with the yarn of the cooling groove in the weaving zone, as regards the method variant of guiding the yarn through a plurality of yarn guides arranged upstream and downstream of the cooling groove, In this case, it is particularly advantageous for the cooling groove to have a curved groove bottom between the yarn guides in the yarn running direction. In particular, the angle at which the yarn enters the cooling groove and the angle at which it is guided out of the cooling groove can thus be set in a particularly precise and reproducible manner. Due to the yarn guides, no individual adaptations are required in the machine or in the weaving area.

In order to make the environment as vapor-free as possible, a modification of the method according to the invention is provided with regard to the collection and suction of the vapor generated by wetting the yarn in cooling troughs. The trapping and venting of vapors is particularly advantageous in view of the parallel processing of many yarns side by side in a weaving machine.

The vacuum connection of the suction system can be arranged in a particularly advantageous manner at the low point of the cooling tank in the outlet area, so that, in addition to the vapour, also unconsumed residues of the cooling liquid are discharged.

In order to carry out the method, the cooling device according to the invention has a metering device for supplying cooling liquid, wherein the metering device has metering means for producing a cooling liquid delivery rate of between 0.05 ml/min and 5 ml/min. Such dosing means are preferably implemented with metering pumps, which generate a continuous and uniform delivery flow of cooling liquid and which can be fed to the cooling tank.

The cooling liquid is applied to the yarn passing through the specific cooling zone in the cooling tank. For this purpose, the cooling grooves on the cooling body are formed with a length of between 100 mm and 300 mm.

In order to intensify the cooling effect, the cooling channel provided in the channel floor has a plurality of recessed pockets which are separated from each other for the guide web used in the channel floor.

Here, the guide web between the pockets on the bottom of the cooling tank can be configured with the same web width and/or with differently dimensioned web widths in order to carry out the feeding of the yarn in the cooling tank. Yarn guidance and wetting.

In order to be able to guide the yarn in a reproducible manner, a particularly advantageous development of the device according to the invention relates to a uniform contact in the bottom of the cooling groove, after at least one yarn guide is arranged upstream of the cooling groove and one yarn guide is arranged at Downstream, and with respect to the cooling groove, there is a curved groove bottom in the yarn running direction.

In order to collect and discharge the vapours, an improvement of the device according to the invention is provided in that the cooling body is equipped with suction facilities on the cooling channel. The suction device is preferably configured so that, in addition to the vapour, fluid residues of the cooling fluid that may form in the outlet area can be discharged from the cooling tank. Environmental stress on the weaving machine can thus be avoided.

The method according to the invention for cooling synthetic yarns in the weaving zone of a weaving machine will be explained in more detail below using several exemplary embodiments of the device according to the invention with reference to the accompanying drawings.

Figure 1 schematically shows a section of a weaving machine, in particular the weaving zone. For this purpose, the weaving machine has a supply package position 4 in which a supply package 2 of yarn 3 is held. Yarn 3 was previously manufactured as partially oriented yarn (POY) by a melt spinning process. The first transfer unit 1 . 1 is assigned to the supply packaging position 4 . In this exemplary embodiment, the transport unit 1.1 is formed by a godet unit with a plurality of cladding materials. The first transfer unit 1.1 forms a yarn run-in into a so-called weaving zone extending as far as the second transfer unit 1.2. The second transport unit 1.2 is likewise formed by a guide roller unit with a plurality of cladding materials. The guide roller units of the transfer units 1.1 and 1.2 are shown here as examples. In principle, in the case of thread guidance with gaps between the driven shaft and the contact rollers and/or contact belts, so-called nipping transfer units for thread guidance can also be used.

The heating device 5, the cooling device 6 and the false twisting device 7 are arranged in the yarn running direction in the weaving area extending between the transfer units 1.1 and 1.2. The cooling device 6 is formed by a device according to the invention and is shown in detail in FIGS. 2 and 3 .

An exemplary embodiment of the cooling device 6 according to the invention shown in FIGS. 2 and 3 is shown schematically in longitudinal section in FIG. 2 and in cross-section in FIG. 3 . The following description applies to both figures as long as no explicit reference is made to either of these figures.

An exemplary embodiment of the cooling device 6 according to the invention has an elongated cooling body 10 . The cooling groove 11 extends on the upper surface of the heat sink 10 . The cooling groove 11 extends as far as the end face of the cooling body 10 , wherein the inlet channel thread guide 8 is arranged on the yarn inlet channel 24 and the outlet thread guide 9 of the cooling groove 11 is arranged on the yarn outlet 25 . The cooling groove 11 has an arcuate groove bottom 17, the curvature of which is indicated by the radius R. The cooling section extending between the yarn inlet channel 24 and the yarn outlet channel 25 on the groove bottom 17 is indicated by the section length L in FIG. 2 .

The metering opening 12 in the groove bottom 17 of the cooling groove 11 opens in the region of the yarn inlet channel 24 . The metering opening 12 is connected to a metering facility 13 by means of a metering conduit 12 . 1 and a supply line 26 . In this exemplary embodiment, metering facility 13 has metering member 14 connected to container 20 . The cooling liquid is kept in container 20 . Dosing means 14 is preferably constructed as a metering pump and driven by a motor 15 . The motor 15 is controlled by a controller 16 connected to a machine control unit (not shown here).

The groove bottom 17 in the part of the cooling groove 11 extending between the metering opening 12 and the yarn outlet channel 25 has a plurality of recessed grooves in the groove bottom 17 separated from each other by a plurality of guide webs 19 Bag 18.

It can be seen in particular from the illustration in FIG. 3 that the groove pockets 18 of the groove bottom 17 form depressions in which cooling liquid can accumulate. The yarn 3 is guided in contact on the surface of the guiding web 19 .

It can be seen from the illustrations in FIG. 2 and FIG. 3 that the suction facility 21 is disposed above the cooling tank 11 . The suction device 21 has a suction sleeve 23 extending over the entire length and width of the cooling tank 11 on the cooling body 10 . A suction sleeve 23 is connected to a vacuum source 22 whereby vapors generated by the cooling liquid as the yarn cools can be collected and discharged. A vacuum source 22 , which may be constructed as a blower, may advantageously operate a plurality of adjacent suction cannulae 23 .

At this point it should be made clear that this is an exemplary embodiment of the structure of the cooling device according to the invention. Suction means 21 can therefore also be arranged below the cooling trough in order to be able to additionally collect and discharge especially liquid residues at the yarn outlet.

From the illustration in FIG. 1 it follows that in order to weave the yarn with the false twisting device 7, twist is mechanically produced on the yarn, whereby the filaments of the yarn 3 are twisted. This twist is reversed against the yarn running direction and is usually prevented by so-called twist stops at the entry channel in the weaving zone. Thus, the twisted yarn 3 in the heating device 5 is heated to a temperature of about 200°C. In order to cool the hot yarn in order to set the crimp, the yarn 3 is supplied to the cooling device 6 with the inlet channel yarn guide 8 . In order to cool the twisted yarn, the metering member 13 generates a cooling liquid with a predetermined delivery rate, which is continuously introduced into the cooling tank 11 through the nozzle openings 12 . Here the delivery rate is set between 0.05 ml/min and 5 ml/min whereby on the one hand a proper cooling of the yarn is established and on the other hand no substantial amount of excess cooling liquid is established for the yarn after leaving the cooling tank 11 . By virtue of the twisted state of the yarn 3, the liquid for cooling is prevented from taking-up, so that, depending on the yarn count, the cooling grooves are formed with a certain segment length between 100 mm and 300 mm.

In tests using polyester yarns with a yarn count of 300 den, the yarns could be properly cooled within a cooling section of 225 mm. Water is used as cooling liquid, wherein, depending on requirements, a small amount of oil, eg 1%, can be added to the water. The quantity of cooling liquid is about 4 ml/min.

It has been determined that twisted yarns can be cooled more effectively with cooling liquid in amounts between 5 and 15% of the yarn weight. Thus, liquid residues at the end of the cooling program can be minimized. Therefore, the method of the invention and the device of the invention are particularly outstanding due to the proper cooling of the yarn during the weaving process with a minimum of cooling liquid. No complicated liquid residue collection and preparation is required.

Furthermore, the yarn guides 8 and 9 used on the yarn inlet channel 24 of the cooling device 6 and on the yarn outlet channel 25 have the possibility to pre-set the yarn guides so that reproducible and identical Yarn guide. Due to them complex setting operations in the weaving machine and in the weaving area can be dispensed with.

In the exemplary embodiment shown in FIG. 2 , the bottom 17 of the cooling tank 11 is organized in the cooling body 10 with uniform pockets 18 such that the guide webs 19 between the pockets are each of the same size. web width. In principle, however, it is also possible to design the web width of the guide web 19 in the groove bottom 17 to be of different lengths. For this purpose, FIG. 4 illustrates an exemplary embodiment of a cooling device according to the invention constructed as guide webs 19 with different web widths. The exemplary embodiment of FIG. 4 itself is otherwise identical to the exemplary embodiment of FIG. 2 itself, wherein the suction means 21 and the metering means 13 are not shown here. In the exemplary embodiment of FIG. 4 itself, the guide web 19 in the exit channel area is constructed substantially wider than the remaining area of the cooling slot 11 . The supply of cooling liquid to the yarn can be enhanced by means of groove pockets 18 in the groove bottom 17 of the cooling groove 11 , whereby relatively short cooling sections and thus relatively short cooling grooves 11 can be realized on the cooling body 10 . However, it is also possible to construct the cooling tank 11 without tank pockets.

FIG. 5 shows an exemplary embodiment of the cooling device according to the invention in the case of the cooling tank 11 of the tank bottom 17 without tank pockets 18 . The illustration of the suction system 21 and the metering system 13 is also omitted here. In this case, the yarn 3 is guided in interrupted contact on the groove bottom 17 of the cooling groove 11 . The cooling liquid introduced here by means of the metering opening 12 into the cooling channel 11 is evenly distributed on the channel wall of the cooling channel 11, is evaporated to the yarn outlet channel 25 or is absorbed and carried away by the yarn.

In the exemplary embodiment of the device according to the invention shown in FIG. 5 , the metering duct 12.1 opens into the cooling groove 11 at an inclination to the yarn running direction. The conveying flow of the cooling liquid is thus already aligned in the yarn running direction, which facilitates the distribution in the cooling groove 11 .

From the foregoing discussion, it will be appreciated that the present invention may be embodied in a variety of embodiments, including but not limited to the following: Embodiment 1. A method for cooling synthetic yarns in the weaving zone of a weaving machine, the method comprising: introducing a cooling liquid into a cooling groove of a cooling body, the method comprising: distributing the cooling liquid in the in the bottom of the cooling groove, and the method comprises: guiding the hot yarn through the cooling groove in a contacting manner, characterized in that, depending on the yarn count of the yarn, the cooling liquid is fed through a metering opening to the bottom of the cooling tank at a delivery rate of between 0.05 ml/min and 5 ml/min middle. Embodiment 2. The method of embodiment 1, wherein the yarn in a cooling section on the bottom of the cooling groove is guided by a section length between 100 mm and 300 mm . Embodiment 3. The method of embodiment 1 or 2, wherein the cooling liquid is distributed within the cooling tank across a plurality of successive pockets in the tank bottom, and wherein the yarn is guided in a contacting manner The line runs over a plurality of webs assembled between the slot pockets. Embodiment 4. The method according to any one of embodiments 1 to 3, wherein the yarn is guided through a plurality of yarn guides arranged upstream and downstream of the cooling tank, and wherein the cooling tank is located between the There is a groove bottom which is arc-shaped in the running direction of the yarn between the yarn guides. Embodiment 5. The method according to any one of embodiments 1 to 4, wherein the vapor generated by the wetting of the yarn is collected and sucked in the cooling tank. Embodiment 6. A kind of cooling device, it is used for carrying out the method as any one in embodiment 1 to 5, and it has a cooling body useful for guiding the elongated cooling groove of this yarn, and wherein, the cooling The tank is connected with a metering opening in the tank bottom to a metering facility for supplying a cooling liquid, It is characterized in that the metering device has a controllable metering member for producing a cooling liquid delivery rate between 0.05 ml/min and 5 ml/min. Embodiment 7. The cooling device as in embodiment 6, wherein the cooling groove has a length between 100 millimeters and 300 millimeters on the cooling body. Embodiment 8. The cooling device as in embodiment 6 or 7, wherein the cooling tank has a plurality of recessed pockets in the tank bottom that are separated from each other by a guide web in the tank bottom. Embodiment 9. The cooling device of embodiment 8, wherein the guide webs between the slot pockets on the slot bottom are constructed to have the same sized web width and/or have different sized web widths Web width. Embodiment 10. The cooling device according to any one of embodiments 6 to 9, wherein the at least one yarn guide is disposed upstream of the cooling tank, and a yarn guide is disposed downstream of the cooling tank, and wherein the cooling tank has A groove bottom that is curved in the yarn running direction. Embodiment 11. The cooling device according to any one of embodiments 6 to 10, wherein the cooling body is equipped with a suction facility for collecting and discharging vapor on the cooling tank.

1.1: The first transmission unit 1.2: The second transmission unit 2: Supply packaging 3: Yarn 4: The position of feeding and packaging 5: Heating device 6: cooling device 7: False twisting equipment 8: Import channel yarn guide 9: Export yarn guide 10: Elongated cooling body 11: cooling tank 12:Metering opening/nozzle opening 12.1: Metering catheter 13: Metering facilities 14: metering member/dosing member 15: Motor 16: Controller 17: Arc groove bottom 18: Depression groove bag 19: guide web 20: container 21: Suction facility 22: Vacuum source 23: Suction cannula 24: Yarn inlet channel 25: Yarn outlet channel 26: Supply pipeline L: segment length R: Radius

In the attached picture:

Figure 1 schematically shows the weaving zone of a weaving machine with an integrated cooling device according to the invention for cooling the yarn;

Fig. 2 schematically shows an exemplary embodiment of the cooling device of the present invention for cooling the yarn of Fig. 1;

Figure 3 schematically illustrates a cross-sectional view of the exemplary embodiment of Figure 2;

Fig. 4 schematically shows a sectional view of another exemplary embodiment of the cooling device of the present invention;

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

1.1: The first transmission unit

1.2: The second transmission unit

2: Supply packaging

3: Yarn

4: The position of feeding and packaging

5: Heating device

6: cooling device

7: False twisting equipment

8: Import channel yarn guide

9: Export yarn guide

10: Elongated cooling body

11: cooling tank

13: Metering facilities

21: Suction facility

Claims (13)

A method for cooling synthetic yarns in the weaving zone of a weaving machine, the method comprising: introducing a cooling liquid into a cooling groove of a cooling body, the method comprising: distributing the cooling liquid in the cooling groove of the in the groove bottom, and the method comprises: guiding the hot yarn through the cooling groove in a contacting manner, It is characterized by: The cooling liquid is fed at a delivery rate through a metering opening into the bottom of the cooling tank in an amount of between 5 and 15% by weight of the yarn. The method of claim 1, wherein the cooling liquid is supplied through the metering opening into the bottom of the cooling tank depending on a yarn count of the yarn. The method according to claim 1, wherein the delivery rate is between 0.05 ml/min and 5 ml/min. If the method of claim 1, in: The yarn in a cooling section on the bottom of the cooling slot is guided by a section length between 100 mm and 300 mm. If the method of claim 1, in: distributing the cooling liquid within the cooling tank across successive pockets in the slot bottom, wherein the yarn is guided in a contacting manner across the webs assembled between the pockets . If the method of claim 1, in: The yarn is guided through a plurality of yarn guides arranged upstream and downstream of the cooling groove, wherein the cooling groove has a groove bottom that is arc-shaped in the running direction of the yarn between the yarn guides. If the method of claim 1, in: Vapors generated from the wetted yarn are collected and sucked in the cooling tank. A cooling device for carrying out the method according to any one of claims 1 to 7, the cooling device has a cooling body for guiding an elongated cooling groove of the yarn, wherein the cooling groove is used for a metering opening in the bottom of the tank is connected to a metering facility for supplying a cooling liquid, It is characterized by: The metering means has a controllable metering member for producing a cooling liquid delivery rate between 0.05 ml/min and 5 ml/min. Such as the cooling device of claim 8, in: The cooling groove has a length on the cooling body between 100 mm and 300 mm. Such as the cooling device of claim 8, in: The cooling trough has in the trough bottom a plurality of recessed pockets each separated from each other by a guide web in the trough bottom. Such as the cooling device of claim 8, in: The guide webs between the slot pockets on the slot floor are constructed with identically sized web widths and/or with differently sized web widths. Such as the cooling device of claim 8, in: At least one yarn guide is arranged upstream of the cooling groove, and one yarn guide is arranged downstream of the cooling groove, and wherein the cooling groove has a groove bottom that is arc-shaped in the yarn running direction. Such as the cooling device of claim 8, in: The cooling body is equipped with a suction facility on the cooling tank for collecting and discharging vapors.

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