JP6355652B2 - Method and apparatus for melt spinning and drawing a plurality of multifilament yarns - Google Patents

Description

  The present invention relates to a method of melt spinning and drawing a plurality of synthetic multifilament yarns described in the front part of claim 1, and a method of melting a plurality of synthetic multifilament yarns described in the front part of claim 8. The present invention relates to an apparatus for spinning and drawing.

  In the case of producing a synthetic yarn in the melt spinning process, a plurality of yarns are usually produced as one yarn group at the same time. At this time, at the end of the process, each yarn must have the same physical properties, which places high demands on uniform guidance and processing of all yarns. Since each multifilament yarn is formed from a large number of delicate filament strands, a problem of uniformity occurs particularly during heat treatment. This is because the individual filament strands within the yarn must be temperature controlled uniformly, especially when the yarn is drawn. For example, when uniform temperature adjustment of the yarn is insufficient, it is known that non-uniformity, that is, unevenness occurs when the yarn is colored.

  In order to eliminate such a problem, in the known method and device according to the prior art described in DE 102001001717, the yarn is one band, i.e. after cooling and before drawing, respectively. It is spread on a strip. For this purpose, a plurality of oil application rollers are correspondingly arranged on the yarn running path between the spinning device and the drawing device, and these oil agent application rollers guide each yarn not only in a wet state but also in a belt shape. Is possible. Known methods and known devices are used in particular for technical yarns in which the multifilament yarn has a relatively small number of filament strands with a high yarn count. At this time, the yarn is guided by being wound around the heated godet peripheral wall of the godet several times, and on the other hand, a long residence time can be obtained between the yarn and the heated peripheral wall surface of the godet. And on the other hand, the yarn can be heated from both sides by being wound alternately. Therefore, such known methods and known devices require a long godet unit.

  However, in the method and device for producing textile yarns known from DE 102008039378, the heating and drawing of the yarn is effected by a single winding in the godet. In this known arrangement, a yarn brake is arranged immediately upstream of the drawing device, and this yarn brake enables the strip-like expansion of the multifilament yarn. Thereby, the contact between the filament strand in the filament bundle and the surface of the heated godet peripheral wall of the godet can be made uniform. In such a known method and known apparatus, an annular guide groove is provided on the godet peripheral wall of the godet, and these guide grooves particularly prevent the yarn from spreading due to electrostatic charges. Such a guide groove prevents the individual yarns from being guided in a strip shape.

  Therefore, an object of the present invention is to improve the method and apparatus for melt spinning and drawing a plurality of multifilament yarns of the type described in the preceding section, and to guide the yarn by one partial winding in the godet during the production of the yarn. Is to achieve high uniformity in yarn processing.

  According to the present invention, this problem is solved by obtaining an electrostatic charge immediately before the yarn comes into contact with the heated godet peripheral wall of one of the godets.

  The present invention is freed from the condition that the electrostatic charge generated in the synthetic yarn should not be discharged on the godet peripheral wall. For example, it is known that electrostatic discharge in godets can damage bearings. However, it has been found that in the melt spinning process, the yarn is only slightly discharged and the charge energy that causes the filaments to expand inside the yarn remains substantially maintained. Therefore, the electrostatic charge inside the yarn can be suitably used to obtain a strip-shaped guide of the yarn on the godet peripheral wall, which is forced by the charge energy. In this way, the heat treatment and heating of the yarn can be further improved.

  Charging the yarn with static electricity prior to the godet riding on the heated godet peripheral wall is preferably performed simultaneously in all yarns together. In principle, however, it is also possible to carry out electrostatic charging, i.e. electrostatic charges, individually or non-uniformly in each yarn.

  Basically, for the method according to the invention, a charging means which operates without contact or a charging means which operates in contact is used for generating an electrostatic charge in the synthetic yarn. Is also possible. In a preferred embodiment of the method used to simultaneously generate an electrostatic charge in a number of yarns, the yarns are guided through an electric charge generator electric field.

  In order to avoid the reaction of the electrostatic charge spreading properties in the yarn as far as possible, in a particularly preferred embodiment of the method, the electrostatic charge of the yarn is generated by contact with one or more friction elements.

  At this time, especially for yarn groups, it has been shown that a method embodiment in which the yarns are guided together via a knife-like guide edge is preferred. In this way, light entanglements in the filament strands of the yarn that are pre-generated by vortexing can be eliminated.

  In order to avoid the mutual influence of the yarns guided as a group, in another aspect of the method, the yarns are guided around the godet peripheral wall with a minimum spacing in the range of 2 mm to 6 mm. In this way, it is ensured that the yarns can be guided in parallel with each other around the godet peripheral wall without contacting the yarns.

  In order to obtain the spreading effect as strong as possible on the one hand and to limit the influence of electrostatic charges on the yarn on the other hand, in a particularly preferred embodiment of the method, the yarn is drawn and stretched dry after spinning. The yarn is wetted with liquid after drawing. In this way, it is not necessary to overcome the additional adhesive force inside the yarn in order to spread the filament of the yarn when the yarn enters the drawing device.

  The device according to the present invention is distinguished by the fact that charging means for generating an electrostatic charge in the yarn is arranged correspondingly on the yarn entry side of the drawing device. Such a combination of charging means and stretching device with godets is surprisingly possible. This is because the charge energy remains maintained in the yarn and remains effective without prior discharge, substantially through multiple godet peripheral walls. Thus, the device according to the invention can produce both fully drawn and partially drawn yarns.

  The charging means can be formed by an electrical charge generator that produces a common electric field through which the yarn passes in order to process a plurality of yarns together.

  Alternatively, however, the charging means can also be formed by one or more friction elements which are guided in contact with the yarn. With this construction, charge energy can be suitably generated in the yarn as extremely desired.

  In melt spinning, especially in unwet yarns, it is common to perform a vortex after spinning and before drawing in the yarn to obtain a first yarn bond between the yarns. Inside the filaments are individually entangled. Such an entanglement of filaments in the yarn can be advantageously eliminated by means of the device according to the invention in which the friction element is formed by a knife-like guide edge made of ceramic material. As a result, the yarn swirled in advance can be suitably expanded by charging static electricity.

  In another aspect of the present invention that favorably facilitates the guide of the yarn inside the drawing device, guide means for guiding the yarn separately with a yarn spacing in the range of 2 mm to 6 mm is arranged upstream of the charging means. Has been. If comprised in this way, the mutual overlap of the thread | yarn in the surrounding surface of a godet surrounding wall can be avoided.

  In order to discharge the electrostatic charge of the yarn at the end of the drawing process, in another aspect of the invention, a dampening device capable of wetting the yarn with a liquid is arranged downstream of the drawing device.

  The method according to the invention and the device according to the invention are basically suitable for all general-purpose melt spinning processes for producing multifilament yarns. It is thus possible to produce partially drawn, fully drawn or highly drawn synthetic yarns for the textile or technical field of use.

  Next, the present invention will be described in detail with reference to the drawings with respect to several embodiments of the apparatus according to the present invention.

1 is a side view schematically showing a first embodiment of an apparatus according to the present invention. FIG. 2 is a front view schematically showing the embodiment shown in FIG. 1. It is the schematic which shows partially the extending | stretching apparatus of embodiment shown in FIG. It is a side view which shows schematically another embodiment of the apparatus which concerns on this invention. FIG. 5 is a front view schematically showing the embodiment shown in FIG. 4. It is a side view which shows roughly one embodiment of a charging means.

  1 and 2 schematically show a first embodiment of an apparatus according to the present invention for melt spinning and drawing a plurality of multifilament yarns, which are synthetic yarns, viewed in another direction. Yes. 1 is a side view of the present embodiment, and FIG. 2 is a front view of the present embodiment. Unless specifically referred to one of the drawings, the following description is for both drawings.

  The present embodiment includes a spinning device 1, a cooling device 3, and a drawing device 10. These devices are arranged one above the other so that when a plurality of synthetic multifilament yarns are manufactured, A vertically oriented yarn path can be obtained.

  The spinning device 1 has a spinning beam 8, and the spinning beam 8 includes a plurality of spinning nozzles 2 below the spinning beam 8. In the present embodiment, four spinning nozzles 2 are held in the spinning beam 8, and each of these spinning nozzles 2 generates a large number of filament strands of one multifilament yarn. Each spinning nozzle 2 held by the spinning beam 8 is connected to a multiple pump (not shown) via a separate melt line. Such a multiple pump (Mehrfachpumpe) is preferably configured as a so-called planetary gear pump. At this time, the polymer melt is supplied through a melt supply passage 4 connected to a multiple pump.

  A cooling device 3 is provided under the spinning device 1, and this cooling device 3 has a blower chamber 19. The air blowing chamber 19 cooperates with the cooling duct 9, and the extruded filament bundle is guided through the cooling duct 9.

  The illustration of the blower chamber 19 and the cooling duct 9 is an example, and the blower chamber 19 and the cooling duct 9 can be arbitrarily configured in relation to the cooling method. For example, it is known that the cooling duct is formed by a plurality of cooling cylinders arranged concentrically with respect to the spinning nozzle and held inside the blower chamber. In such a configuration, the cooling air can be guided from the inner side to the outer side in the radial direction toward the filament bundle. Similarly, the blower chamber can be formed by providing a blower wall on one side of the cooling duct, and this blower wall generates a cooling air flow that flows out in the lateral direction. Therefore, the present invention is not limited to a specific cooling method for multifilament yarns.

  Since each of the extruded synthetic multifilament yarns is formed by a large number of filament strands, the filaments are collected for each yarn at the outlet of the cooling device 3. For this purpose, a plurality of collecting yarn guides 5 are provided. Each of these collective yarn guides 5 is held in the middle of the spinning nozzle 2 arranged on the upstream side, and forms the convergence point of the extruded filament strands that are combined into one yarn 7 respectively.

  Under the cooling device 3, a stretching device 10 is disposed. In the transition region between the cooling device 3 and the drawing device 10, the yarns are grouped by a so-called Spinnteilung, whereby a group of yarns for subsequent processing steps with a relatively small yarn spacing from each other. Can be obtained. Therefore, guide means 6 is arranged on the upstream side of the stretching apparatus 10. The guide means 6 can be formed by individual thread guides or by a single comb-shaped thread guide element.

  In the present embodiment, the stretching apparatus 10 has a plurality of godets 11.1 to 11.4. In this embodiment, the stretching apparatus 10 is composed of a total of four godets 11.1 to 11.4, and these godets have heated godet peripheral walls 12.1 to 12.4, respectively. . The godet peripheral walls 12.1 to 12.4 of the godets 11.1 to 11.4 are driven by the godet motors 13.1 to 13.4, and the yarns are arranged in parallel with each other, and the godet peripheral walls 12.1 to 12 are respectively .4 is partially wrapped around and guided.

  The structure of the stretching device 10 is an example and may be supplemented by an additional driven diverting roller or another driven godet.

  On the supply side of the drawing device 10, charging means 14 is provided between the guide means 6 and the first godet 11.1 for generating an electrostatic charge in the yarn 7. In the present embodiment, the charging means 14 is formed by a charge generator 15, and an electric field generated by the charge generator 15 is generated between the guide means 6 and the godet 11.1 in the charge generator 15. Occurs on the yarn runway.

  In order to explain the function of the charging means 14, reference is additionally made to FIG. 3, which is a partial view on the supply side of the stretching apparatus 10. As can be seen from the illustration in FIG. 3, the yarns 7 are supplied to the drawing apparatus 10 in parallel with each other at a processing interval. The processing interval determined by the guide means 6 is indicated by B in FIG. Before the thread 7 rides on the surface of the heated godet peripheral wall 12.1 of the first godet 11.1, the thread 7 passes through the charge generator 15 and the electric field generated thereby, so that the thread 7 7 is charged with static electricity. Due to this electrostatic charge, the electrostatic charge generates a repulsive force that separates the filaments from each other in the filament strands, and thus a force that causes the filament strands to expand in the yarn. The yarn 7 thus charged reaches the surface of the godet peripheral wall 12.1 with the diffused filament bundle. Thereby, almost all filaments can be brought into contact with the peripheral surface of the heated godet peripheral wall 12.1 of the godet 11.1 and heated uniformly.

  In order to avoid the mutual influence of the yarn 7, the processing interval B is adjusted to the minimum value in the range of 2 mm to 6 mm. The processing interval B is adjusted by the guide means 6 disposed on the upstream side of the charge generator 15.

  As can be seen from the illustration in FIG. 2, the yarns 7 are guided together as one yarn group through the godet peripheral walls 12.1 to 12.4. In order to stretch the yarn 7, a speed difference is set between the godet 11.2 and the godet 11.3, so that the original stretching zone is between the godet 11.2 and the godet 11.3. Is formed. At this time, it was observed that the spreading effect remained maintained in the yarn over the subsequent godets 11.2 to 11.4, since the charge in the yarn hardly weakened. As a result, the heat treatment necessary for the relaxation treatment of the yarn can be carried out with extremely high uniformity.

  As can be seen from the illustrations in FIGS. 1 and 2, the stretching device 10 has a dampening device 16 correspondingly disposed immediately below on the running side, and the dampening device 16 causes the yarn 7 to be the last godet peripheral wall. Immediately after running from 12.4, it is wetted by oil (Praeparationsfluessigkeit). This preferably provides a discharge in the yarn, so that the yarn can then be wound, for example, to form a bobbin.

  In the embodiment of the device according to the invention shown in FIGS. 1 and 2, the method according to the invention for melt spinning and drawing synthetic multifilament yarns is carried out in parallel on four yarns. The number of yarns is an example. Basically, the method according to the invention and the device according to the invention are suitable for producing a large number of yarns simultaneously.

  In order to explain the function of the method according to the invention and the device according to the invention, the thread runway of the yarn is shown schematically in FIGS. First, a plurality of delicate filament strands are extruded through the spinning nozzle 2 from the polymer melt. The delicate filament strands extruded for each spinning nozzle 2 are collected by the collecting yarn guide 5 after cooling. In the present embodiment, such yarn grouping is performed without wetting of the yarn, so that the yarn is pulled out from the spinning device 1 in a substantially dry state. The dry state of the yarn 7 is particularly suitable for obtaining an expansion within the yarn which is caused by the subsequent electrostatic charge.

  The yarns 7 are drawn out from the spinning device 1 together as one yarn group, and after being collected, are arranged by the guide means 6 at a processing interval B necessary for subsequent processing. This processing interval B is in the range of 2 mm to 6 mm. Next, the yarn 7 is charged with static electricity by the charging means 14, whereby the filament strands can be expanded by charging in the filament composite. The electrostatically charged yarn 7 is then immediately guided through the heated godet peripheral walls 12.1-12.4 of the godets 11.1-11.4 for heating and drawing. After advancing from the drawing apparatus 10, the yarn is wetted by the oil agent. As a result, discharge of the filament strands and wetting of the filament strands are performed, so that the filament strands are gathered in each yarn.

  Therefore, the method according to the invention and the device according to the invention make it possible in particular to heat-treat and draw even in a plurality of filament strands forming a single yarn. Since each filament strand has the same polymer structure mainly due to temperature and drawing, the yarns produced are particularly suitable for textile applications with high uniformity with respect to coloration.

  The charging of the synthetic filament strands of the yarn is particularly gentle in a non-contact manner according to the embodiment shown in FIGS. 1 and 2, so that yarns with very fine filament strands can also be produced. In addition, unlike the embodiment shown in FIGS. 1 and 2, it is also possible to obtain a yarn joint (Fadenschluss) by first wetting the yarn after spinning, and the yarn is then statically applied in the electric field of the charge generator. Charge can be obtained.

  In the case where the yarn is guided from the spinning device to the drawing device in a dry state, it is usual that the yarn coupling portion is further formed by vortex operation (Verwirbelung). Such a device is shown schematically in FIGS. 4 and 5 when viewed in another direction.

  FIG. 4 shows a front view of an embodiment of the apparatus according to the present invention for melt spinning and drawing a plurality of synthetic multifilament yarns, and FIG. 5 shows a side view thereof. Since this embodiment is substantially the same as the above-described embodiment shown in FIGS. 1 and 2, only the differences will be described below, and the above description will be referred to for others. The following description is for both FIG. 4 and FIG.

  In the embodiment of the device according to the invention shown in FIGS. 4 and 5, the yarn is swirled after melt spinning and before drawing. For this purpose, a vortex device 20 is provided between the cooling device 3 and the stretching device 10. The vortex device 20 has a vortex nozzle 21 for each yarn, and the vortex nozzle 21 mixes filament strands in the yarn 7 using a compressed air flow.

  However, such entanglement of the filament strands in the yarn 7 can cause a situation in which the electrostatic charge of the filament strands can only act insufficiently to spread the yarn. In order to eliminate such entanglement as much as possible, in the embodiment shown in FIGS. 4 and 5, the charging means 14 is formed by a friction element 17. The friction element 17 has a knife-like guide edge 18, and the yarn 7 is guided in contact with the guide edge 18. The guide edge 18 is preferably formed from a wear-resistant ceramic material, at which time the dried filament strands are charged with static electricity by friction. Due to the frictional contact between the yarn 7 and the guide edge 18 of the friction element 17, the confounding caused by the preliminary vortex can be preferably minimized. In this way, the yarn 7 is guided through the godet peripheral walls 12.1 to 12.4 of the godets 11.1 to 11.4 in an expanded state.

  At this time, the function for heating and stretching the yarn 7 is the same as that of the embodiment already described.

  It is also possible to arrange a plurality of friction elements on the yarn runway in order to achieve not only the electrostatic charge but also the release of possible confounding. FIG. 6 shows one embodiment of such a charging means that can be used, for example, in the embodiment shown in FIGS. FIG. 6 schematically shows the charging means 14 in a side view. At this time, the yarns 7 that run in are arranged by the guide means 6 in accordance with the processing interval necessary for the subsequent processing. Here, the guide means 6 is formed as a comb-tooth guide 22 having one guide groove (only schematically) for each yarn 7.

  Under the comb tooth guide 22, the charging means 14 is formed by a plurality of friction elements 17. The friction element 17 is formed as an edge yarn guide 23 having a semicircular cross section. The friction elements 17 are arranged so as to be displaced from each other. At this time, the rounded chamfered shape of the edge yarn guide 23 is directed toward the thread 7 that enters, that is, faces upward. The running of the yarn takes place in the friction element 17 on the underside of each of the edge yarn guides 23 having a relatively sharp edge. Since the edge yarn guide 23 is formed in a rod shape, a plurality of yarns can be guided in parallel with each other. The edge yarn guide 23 is preferably made from a ceramic material.

  In the illustrated embodiment of the charging means 14, a total of four friction elements 17 are arranged one after the other on the yarn path. The number of friction elements 17 is basically arbitrary. However, the number of friction elements 17 can affect the electrostatic charge on the yarn. For example, in a non-vortexed yarn, it is possible to use a relatively large number of curved contact surfaces that are offset from each other as the friction element 17, thereby spreading the yarn by charging the filament with static electricity. Can be opened.

  In the embodiment shown in FIG. 6, the friction element 17 is normally held by one or more supports. At this time, it is also possible to hold at least a part of the friction element 17 movably in order to change the degree of yarn winding. In this way it is possible to adjust and influence the friction produced in the filament strands.

  In the embodiment of the apparatus according to the present invention shown in FIGS. 1, 2, 4, and 5, the arrangement and number of godets in the stretching apparatus are merely examples. Basically, an unheated or heated driven godet or an unheated turning roller can additionally be incorporated inside the stretching device. Important for the method according to the invention and the device according to the invention is that the static electricity is charged in order to achieve strong yarn contact with all filament strands of the yarn around the heated godet peripheral wall. It is to guide the thread.

  The method according to the invention and the device according to the invention are suitable for producing a synthetic multifilament yarn having a small or large count. Both textile yarns and technical yarns can be suitably produced.

DESCRIPTION OF SYMBOLS 1 Spinning device 2 Spinning nozzle 3 Cooling device 4 Melt supply path 5 Collected yarn guide 6 Guide means 7 Yarn 8 Spinning beam 9 Cooling duct 10 Drawing device 11.1-11.4 Godet 12.1-12.4 2.4 Godet peripheral wall 13 .1 to 13.4 Godet motor 14 Charging means 15 Charge generator 16 Dampening device 17 Friction element 18 Guide edge 19 Blower chamber 20 Vortex device 21 Vortex nozzle 22 Comb tooth guide 23 Edge yarn guide

Claims (11)

A method of melt spinning and drawing a plurality of synthetic multifilament yarns, wherein the yarns are juxtaposed in parallel to each other and extruded from the polymer melt, and after cooling the yarns, a plurality of heated godets of a plurality of driven godets In a circumferential wall, the godet circumferential wall is at least partially wrapped around, guided and heated, and the yarn is drawn by at least one speed difference between a plurality of godets,
The yarn is given an electrostatic charge before contact with the heated godet peripheral wall of one godet of the plurality of godets ,
A method of melt spinning and drawing a plurality of multifilament yarns, wherein the yarn is drawn and drawn in a dry state after spinning, and the yarn is wetted with a liquid after drawing.   The method of claim 1, wherein the electrostatic charge of the yarn is generated together or individually in the plurality of yarns.   3. The method according to claim 1, wherein the electrostatic charge of the yarn is generated in a contactless manner by means of an electrical charge generator.   4. A method according to any one of claims 1 to 3, wherein the electrostatic charge of the yarn is generated by contact with one or more friction elements.   5. A method according to claim 4, wherein the yarns are guided together through a knife-like guide edge.   6. The method as claimed in claim 1, wherein the yarns are guided around the godet peripheral wall with a minimum distance in the range of 2 mm to 6 mm. An apparatus for melt spinning and drawing a plurality of synthetic multifilament yarns, a spinning device (1) having a plurality of spinning nozzles (2) for extruding the plurality of multifilament yarns (7), and a yarn (7) A cooling device (3) for cooling the yarn and a drawing device (10) for drawing and drawing the yarn (7), the drawing device (10) comprising a plurality of heated godet peripheral walls (12.1). In a device having a plurality of driven godets (11.1 to 11.4) with
A charging means (14) for generating an electrostatic charge in the yarn (7) is arranged correspondingly on the yarn entry side of the drawing device (10), and the yarn (7) is arranged on the downstream side of the drawing device (10). A device for melt spinning and drawing a plurality of multifilament yarns, characterized in that a dampening device (16) that is wettable by a liquid is arranged . Charging means (14), the thread (7) is formed by an electrical charge generator give rise to common electric field that passes through (15), The apparatus of claim 7, wherein. 8. The device according to claim 7 , wherein the charging means (14) is formed by one or more friction elements (17) to which the yarn is guided in contact. 10. The device according to claim 9 , wherein the friction element (17) has a knife-like guide edge (18) made of ceramic material. The upstream side of the charging unit (14), another thread spacing guide means (6) to (B) with the thread (7) for separately guiding is arranged in the range of 2 mm to 6 mm, from the claims 7 10 The device according to any one of the above.

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