WO2010130591A1

WO2010130591A1 - Method and device for melt spinning and cooling a plurality of monofilaments

Info

Publication number: WO2010130591A1
Application number: PCT/EP2010/055966
Authority: WO
Inventors: Bert Wöllner; Kenneth Schindler
Original assignee: Oerlikon Textile Gmbh & Co. Kg
Priority date: 2009-05-13
Filing date: 2010-05-03
Publication date: 2010-11-18
Also published as: DE102009021117A1; US20120112381A1; DE112010001983A5

Abstract

The invention relates to a method and a device for melt spinning and cooling a plurality of monofilaments which are extruded through a plurality of openings of a spinneret and guided into a cooling bath. The removal process consists of redirecting the monofilaments within the cooling bath. According to the invention, in order to prevent adhesion and an oblique pull-off, the monofilaments are divided into multiple filament groups after extrusion, said groups consisting of multiple monofilaments, and the filament groups are individually redirected independently of each other within the cooling bath into multiple redirecting positions by separate redirecting sheaves.

Description

Method and apparatus for melt spinning and cooling a plurality of monofilaments

The invention relates to a method for melt spinning and cooling a plurality of monofilaments according to the preamble of claim 1 and to an apparatus for melt spinning and cooling a plurality of monofilaments according to the preamble of claim 7.

In the manufacture of monofilaments from a thermoplastic material, it is common for the monofinals to be sent immediately after cooling for cooling into a water-filled cooling bath. This makes it possible to realize short cooling sections in the melt spinning process even with larger filament titers. Within the cooling bath, it is necessary to lead the monofϊ parliamente out of the cooling bath for further processing, in particular for drawing. Thus, the Monofϊlamente be deflected within the cooling bath by at least one deflection means for removal from the cooling bath. In this case, it is necessary for the monoblocks extruded through the nozzle openings on the underside of the spinneret to be guided together to a deflecting means, for example a deflection bar or a deflection roller. For this purpose, all extruded Monofϊlamente be led to a deflection position of the deflection, on which they are guided tangentially next to each other together.

Such a method and such a device are known for example from DE 196 00 090 Al.

In the known method and the known device, a plurality of deflection means arranged behind one another are arranged within a cooling bath in order to obtain as gentle as possible a deflection of the monoblocks. In this case, the monofiners are all led to a first deflection position of the first deflection means after extrusion. Depending on the distance between the spinneret and the deflecting means, larger deflections are required. of the extruded Monofϊ parliamente in the edge region of the spinneret unavoidable. Such skew on the monofilaments causes stress differences, which in turn affect different crystallization of the fiber material and quality differences in the monofilaments. In addition, in the case of a large number of monofilaments, the danger of contacting when the monofilaments are brought together in the deflection position is increased, so that individual monofilament bonding is unavoidable. In particular, such problems occur in the melt spinning of monofilaments, which are cooled exclusively by a cooling liquid in a cooling bath. In such methods and devices in particular very short distances between the spinneret and the deflection means are to be bridged within the cooling bath.

It is therefore an object of the invention to improve a method and apparatus for melt spinning and cooling a plurality of monofilaments of the generic type such that a large number of monofilaments are extruded and cooled under uniform conditions as possible.

This object is achieved according to the invention for a method for melt spinning and cooling a plurality of monofilaments in that the monofilaments are divided into several filament groups of several monofilaments after extrusion and that the filament groups are deflected independently within the cooling bath in several deflection positions.

The solution of the device according to the invention is given by the fact that the deflection means are arranged below the spinneret such that the monofilaments are divisible after extrusion into a plurality of filament groups of several monofilaments and that the filament groups are deflected independently within the cooling bath in several deflection individually , Advantageous developments of the invention are defined by the features and feature combinations of the respective subclaims.

The invention makes possible a substantially straight draw of the monofilaments in the region between the spinneret and the deflection means. The deflection positions can be matched within the cooling bath in each case to the monofilaments of the filament group and the position of the nozzle openings for extrusion at a spinneret. The adaptation of the relative positions of the nozzle openings on the spinneret and the deflection positions in the cooling bath to one another enables a uniform removal of the monofilaments from the spinneret. In addition, this ensures that each of the monofilaments passes through an equal length of cooling air in the ambient air until it reaches the cooling liquid.

To minimize the friction during deflection of the filament groups acting on the monofilaments as much as possible, is provided according to an advantageous development of the invention that the filament groups are deflected in the deflection each by individually freely rotatable pulleys. For this purpose, each of the deflection means is formed by a freely rotatable deflection roller, so that the filament groups in the deflection positions can be guided with low friction even with larger deflection angles of> 90 °.

In order to limit the number of monofilaments required for the deflection of the monofilaments deflection number in a very large number, the development of the invention is particularly advantageous in which the monofilaments within their filament after extrusion between the spinneret and the deflection with a maximum deflection of> 5 °. In the apparatus according to the invention, the layers and / or the number of deflecting means below the spinnerets are selected for this purpose so that the monofilaments, when withdrawn from the spinneret, avoid a deflection angle of> 5 °. In principle, the positions and number of deflecting means can be adapted to the respective position and arrangement of the nozzle openings on the underside of the spinneret. Preferably, however, the monofilaments are extruded side by side in an annular arrangement, wherein the distribution of the filament groups advantageously also takes place within the annular arrangement. For this purpose, the deflection means are preferably positioned below the spinneret in an arrangement congruent with the formation of the filament groups to the nozzle openings of the spinneret.

Depending on the filament titer of the monofilaments and depending on the polymer material, it is necessary to allow different lengths of cooling sections. This can be advantageously realized by the development of the invention, in which the deflection of the filament groups are made adjustable. For this purpose, the deflection means are preferably arranged on a plate-shaped holder, which is designed to be movable for adjusting the deflection positions.

Thus, the withdrawal of monofilaments from the cooling bath can preferably be improved in that the holder is connected by a pivot axis with a carrier, through which an angle of inclination is adjustable on the holder. This results in height-offset deflection positions, so that the monofilaments can be led out directly without additional deflection directly from the cooling bath.

The cooling section for cooling the monofilaments is preferably carried out by a height adjustment of the holder. Here, the deflection can be adjusted within the cooling bath for shortening or for extending the cooling section.

- A - Further advantages of the method according to the invention are described below with reference to some embodiments of the device according to the invention with reference to the accompanying figures.

They show:

1 is a schematic side view of a first embodiment; FIG. 2 is a schematic plan view of the embodiment of FIG. 1; FIG. 3 is a schematic view of another embodiment of a cooling bath with integrated deflection means

Fig. 4.1 and Fig. 4.2 different views of the deflection of the embodiment of

Fig. 3 shows schematically a cross-sectional view of a further embodiment of the device according to the invention for carrying out the method according to the invention

1 and 2, a first embodiment of the inventive device for carrying out the method according to the invention is shown in several views. Fig. 1 shows the embodiment schematically in a side view and in Fig. 2, the embodiment is shown in a plan view without spinneret. Unless express reference is made to any of the figures, the following description applies to both figures.

For melt-spinning and cooling a plurality of monofilaments, the exemplary embodiment has a spinneret 1, which is connected to an extruder 2 via a melt feed 3. The spinneret 1 has on its underside a plurality of nozzle openings 4 (here only a nozzle opening shown in partial section). Below the spinneret 1, a cooling bath 5 is arranged, which is preferably filled with a cooling liquid 6 a water. Within the Cooling bath 5 are arranged in the vertical direction below the spinneret a plurality of deflection 7 at a distance from each other. The deflection means 7 are arranged in a congruent arrangement with the nozzle openings 4 on the underside of the spinneret 1 in such a way that the monofilaments extruded from the nozzle openings 4 of the spinneret 1 can be fed to a plurality of filament groups 14 in as straight a run as possible to one of the deflection means 7 , In this example, the nozzle openings are formed in an annular arrangement on the underside of the spinneret 1. As can be seen from the illustration in FIG. 2, the deflection means are accordingly likewise arranged in an annular arrangement in the cooling bath 5. The deflection means 7 are offset in their height within the cooling bath 5 held to each other, so that the filament groups 14 can be led out after deflection of the deflection 7 together in the oblique yarn path in the cooling bath 5.

On the outlet side of the cooling bath 5, a comb-shaped guide rail 12 is arranged, which carries out a separation of the monofilaments of the filament group 14, so that the monofilaments after leaving the cooling bath as a family 15 can be guided.

The cooling bath 5 is a suction device 10 and a deduction 8 downstream. The suction device 10 has a plurality of suction nozzles 11 in order to suck off the cooling liquid adhering to the monofilaments.

The deduction mechanism 8 includes a plurality of cantilevered godets 9, which are driven by a peripheral speed required for pulling off the monofilaments. The take-off unit 8 is executed in this embodiment with a total of four godets 9, at the periphery of the filament 15 is guided with simple wrap.

To carry out the method according to the invention, a granulate of a thermoplastic material is added to the extruder in the device according to the invention 2 abandoned. As the thermoplastic material, for example, polypropylene, polyamide or polyester can be used. After the granules have melted inside the extruder 2, the melt of the thermoplastic material is fed under pressure to the spinneret 1. At the bottom of the spinneret 1, the melt is extruded through the nozzle orifices 4 into a plurality of monofilaments 13. The monofilaments 13 are directly extruded into the cooling liquid 6 of the cooling bath 5. For guiding the monofilaments 13, a plurality of deflection means 7 are provided within the cooling bath 5, so that the monofilaments 13 are divided into several filament groups 14 of a plurality of monofilaments after extrusion and wherein the filament groups 14 independently within the cooling bath 5 in several by the deflection 7th certain deflection positions are deflected individually. The monofilaments 13 are guided essentially between the spinneret 1 and the deflecting means 7 in a straight yarn path without substantial deflections. In particular, this allows the monofilaments 13 to enter the cooling liquid 6 under the same conditions on all monofilaments. Even a high number of monofilaments 13 can thus be cooled substantially uniformly without a difference in tension distortion. This results in a high material uniformity of all monofilaments.

After each of the filament groups 14 are deflected individually by the separate deflection means 7, all monofilaments 13 are separated by withdrawal from the cooling bath 5 by the comb-shaped guide rail 12 so that in the further course for thermal treatment and stretching of the monofilaments parallel guidance of the monofilaments 13 within the filament share 15 is possible.

In the embodiment of the device according to the invention shown in FIGS. 1 and 2, the deflection of the filament groups in the deflection positions is preferably carried out by freely rotatable deflection rollers, so that a low-friction guidance of the monofilaments is possible. However, alternative Steering means such as rods or pins depending on the selected material of the monofilaments.

When the monofilaments are drawn off in several filament groups, it has been found that in order to maintain as uniform a quality as possible on all monofilaments, the deflection of the monofilaments during extrusion and entry into the cooling liquid should be as <5 ° as possible. In this case, the deflection angle between the thread guide and a central axis running vertically to the nozzle opening is to be considered as the deflection angle. For example, in the case of a single-row annular arrangement of the nozzle openings 4 on the underside of the spinneret 1, position the deflection means 7 in a central axis of a nozzle opening 4. The nozzle openings 4 adjacent to both sides of the nozzle opening 4 could be assigned to the same deflection means 7, so that the monofilaments 13 extruded from the three nozzle openings together form a filament group 14 assigned to the deflection means 7.

In order to be able to design the deflection positions within the cooling bath 5 as flexibly as possible, a further exemplary embodiment for fixing and arranging the deflection means 7 in a cooling bath 5 is shown in FIG. In this embodiment, the deflection means 7 are formed by freely rotatable deflection rollers 20. The deflection rollers 20 are arranged on a plate-shaped holder 16. The holder 16 is fixed to a carrier 17. The carrier 17 is held via a bottom plate 24 directly to the bottom of the cooling bath 5.

To explain the adjustment of the pulleys and thus to adjust certain deflection positions is taken in addition to the figures 4.1 and 4.2 reference. In Fig. 4.1, the holder 16 fixed to the carrier 17 are shown schematically in a perspective view and in Fig. 4.2 in a plan view. The plate-shaped holder 16 has a central fixing opening 18 with a parallel to the carrier 17 extending fixing collar 19. The fixing collar 19 is connected by a pivot axis 21 and a fixing screw 22 with the carrier 17th connected. The fixing screw 22 is inserted into a guide slot 23 of the Fixierkragens 19, so that by loosening the fixing screw 22 of the fixing collar 19 and thus the holder 16 can be pivoted to an arbitrary inclination. Thus, the deflection rollers 20 held on the holder 16 can be positioned within the cooling bath at different heights relative to each other by tilting the holder 16.

To adjust the height of the holder 16, the pivot axis 21 between the fixing collar 19 and the carrier 17 can be arranged in different positions on the holder 17. For this purpose, the carrier 17 has a plurality of openings for receiving the pivot axis 21.

In order to obtain a directional deflection of the filament groups on the deflection rollers 20 held in an annular arrangement, the holder 16 has two recesses 25.1 and 25.2, so that the deflection rollers 25 facing the recesses 25.1 and 25.2 of the holder 16 are in the same direction as the opposite deflection rollers 20 on the Edge of the holder 16 are looped.

However, the exemplary embodiment shown in FIGS. 3, 4.1 and 4.2 for arranging the deflecting means within the cooling belt is only one possible embodiment variant. FIG. 5 schematically shows a further exemplary embodiment of the device according to the invention for carrying out the method according to the invention in a cross-sectional view. In this embodiment, a support 26 is held on the underside of the spinneret 1 in the center of the spinneret 1, which protrudes with its free end into the cooling bath 5. At the free end of the support 26, a plurality of support arms 27 is arranged spreadingly, each carrying a deflection 7 at their ends. In this case, a filament group 14 with substantially straight-guided monofilaments 13 can be deflected within the cooling bath 5 at each of the deflection means 7, for example a deflection roller. The filament groups 14 are deflected separately from each other by the deflection means 7 held at the ends of the support arms 27 and together a guide roller 29 arranged in the cooling bath 5. About the guide roller 29, the monofilaments 13 are withdrawn as a crowd 15 from the cooling bath 5 and separated by the arranged on the outlet side of the cooling bath 5 guide bar 12. This embodiment is particularly suitable for spinnerets 1 with annular arrangement of the nozzle openings 4. The support 26 fastened to the underside of the spinneret 1 can be formed, for example, by a telephoto-shaped embodiment such that the deflection means 7 can be adjusted in height for adjusting the deflecting positions. Likewise, the support arms 27 can be arranged on a head piece, which is formed pivotable relative to the support 26. In that regard, a direct oblique withdrawal of monofilaments from the cooling bath 5 would be possible.

The method according to the invention and the device according to the invention are therefore particularly suitable for producing a large number of monofilaments of uniform quality. In addition, the handling and the process reliability of the monofilaments can be improved by the coolant. By adjusting the heights and the angle of the deflection means to one another, the residence times in the cooling bath can be changed and adjusted depending on the material of the monofilaments.

LIST OF REFERENCE NUMBERS

1 spinneret

2 extruders

3 melt feed

4 nozzle opening

5 cooling bath

6 cooling liquid

7 deflection

8 deduction mechanism

9 godets

10 extraction device

11 suction nozzle

12 guide rail

13 monofilament

14 filament group

15 flock of monofilaments

16 holders

17 carriers

18 fixation opening

19 fixing collar

20 pulleys

21 pivot axis

22 fixing screw

23 guide slot

24 base plate

25.1, 25.2 recess

26 support

27 support arm

29 leadership role

Claims

claims

1. A method for melt spinning and cooling of a plurality of Monofila- elements, wherein the monofilaments are extruded through a plurality of nozzle openings of a spinneret and fed into a cooling bath and in which the monofilaments are led out during removal by a deflection of the cooling bath, characterized in that the monofilaments after extrusion are divided into several filament groups of a plurality of monofilaments and that the filament groups are independently deflected individually within the cooling bath in a plurality of deflection positions.

2. The method according to claim 1, characterized in that the filament groups are deflected in the deflection positions in each case by individual freely rotatable deflection rollers.

3. The method according to claim 1 or 2, characterized in that the monofilaments are guided within its filament group after the extrusion between the spinneret and the deflection positions with a maximum deflection of <5 °.

4. The method according to any one of claims 1 to 3, characterized in that the monofilaments are extruded side by side in an annular array and divided into the filament groups.

5. The method according to any one of claims 1 to 4, characterized in that a cooling section of Monofϊlamente is set within the cooling bath by adjusting the deflection positions of the filament groups.

6. The method according to claim 1 to 5, characterized in that the Monofϊlamente the filament groups are performed after cooling and redirecting together as a crowd, wherein the deflection positions are kept partially offset in height within the cooling bath.

7. An apparatus for melt spinning and cooling a plurality of Monofϊ- lament (13) with a spinneret (1) having a plurality of nozzle openings (4) for extruding the monofϊ parliamente (13) and above a

Cooling bath (5) is arranged, with a plurality of deflection means (7) for deflecting the Monofϊlamente (13) within the cooling bath (5) and with a deduction mechanism (8) for removing the Monofϊlamente (13) from the cooling bath (5), characterized in that the deflection means (7) are arranged below the spinneret (1) in such a way that the monofilaments (13) can be divided into a plurality of filament groups (14) by a plurality of monofilaments and the filament groups (14) are arranged independently within the cooling bath in several Deflection positions are deflected individually by the deflection (7).

8. The device according to claim 7, characterized in that the deflection means (7) by a plurality of freely rotatable deflection rollers (20) are formed, which are held individually in the deflection positions.

9. Apparatus according to claim 7 or 8, characterized in that the layers and / or number of deflecting means (7) below the spinneret (1) are selected so that the monofilaments (13) within their filament group

(14) after extrusion between the spinneret (1) and the deflection means (7) with a maximum deflection of <5 ° are feasible.

10. Device according to one of claims 7 to 9, characterized in that the nozzle openings (4) of the spinneret (1) in an annular arrangement on the underside of the spinneret (1) are formed and that the deflection means (7) below the spinneret ( 1) are positioned in a congruent to form the filament groups (14) arrangement.

11. Device according to one of claims 7 to 10, characterized in that the deflection means (7) are arranged at a distance from each other on a plate-shaped holder (16), which holder (16) is designed to be movable for adjusting the deflection positions.

12. Device according to claim 10, characterized in that the holder (16) is connected by a pivot axis (21) to a carrier (17), by which an angle of inclination is adjustable on the holder (16).

13. The apparatus of claim 10 or 11, characterized in that the holder (16) is height-adjustable connected to a carrier (17).

14. Device according to one of claims 7 to 13, characterized in that the deflecting means (7) a comb-shaped guide rail (12) outside of the cooling bath (5) is arranged downstream, separated by which the Monofϊlamente the FiIa- groups as a family (15) Monofilaments are navigable.