WO2015014690A1

WO2015014690A1 - Apparatus for melt-spinning and cooling filament strands

Info

Publication number: WO2015014690A1
Application number: PCT/EP2014/065824
Authority: WO
Inventors: Martin Fischer; Claudia Sellhast; Jörg SCHIPPEL
Original assignee: Oerlikon Textile Gmbh & Co. Kg
Priority date: 2013-07-27
Filing date: 2014-07-23
Publication date: 2015-02-05
Also published as: DE102013012530A1

Abstract

The invention relates to an apparatus for melt-spinning and cooling filament strands, which carries at least one spinneret on a spinning beam and has a cooling apparatus for forming a cooling zone beneath the spinneret. In order to receive condensed monomers, a condensation device which forms a condensation zone is arranged between the spinneret and the cooling apparatus. In order to obtain controlled condensation of the monomers, the condensation device is formed according to the invention by a condensation ring arranged coaxially with the spinneret, said condensation ring being connected to the cooling apparatus for temperature control by way of a contact face.

Description

Apparatus for melt spinning and cooling filament strands

The invention relates to a device for melt spinning and cooling of filament strands according to the preamble of claim 1.

In the production of synthetic threads, it is well known that in the extrusion of certain polymers such as polyamides more volatile components such as monomers and oligomers occur that can deposit in an uncontrolled environment. In order to avoid such uncontrolled deposits and soiling below the spinneret in downstream apparatus, various methods have been described in the prior art.

A first variant, from which the invention proceeds, is described for example in DE 38 40 357 AI. In the known apparatus for melt spinning and cooling of filament strands, a condensation device is provided below the spinneret, which forms a condensation zone within a condensation shaft. The condensation duct is associated with a flushing device which continuously generates a flushing liquid along the shaft walls of the condensation shaft. In that regard, the monomers condensed within the condensation zone are taken up by the rinsing liquid and collected at the end of the condensation shaft and removed. A further variant for receiving and removing monomers can be found, for example, in WO 89/03903 A1. In the known Direction for melt spinning and cooling filament strands, a suction nozzle of a suction device is arranged immediately below the spinneret, which dissipates the extruded during the extrusion of the filament strands monomers and oligomers via a suction directly from the spinning zone before cooling.

In principle, however, methods are known in the art in which the monomers and oligomers are removed via the cooling air flow. Thus, DE 10 2011 117 458 A1 discloses a process in which a heating means is provided immediately below the spinneret, by means of which condensation of the monomers and oligomers in the upper region of the cooling apparatus is avoided.

The devices known in the art for melt spinning and cooling filament strands are all based on avoiding direct condensation of the monomers and oligomers in the area of the spinneret. Thus, external agents such as rinsing liquids or suction streams are used to bind and remove the monomers and oligomers. Alternatively, additional heating means are used immediately before cooling to avoid premature condensation of the monomers. However, such borrowings more or less lead to an influence on the spinning and cooling process of the filaments.

It is therefore an object of the invention to provide a device for melt spinning and provide filament strands of the generic type, in which unwanted volatile components in the extrusion of polymers can be bound as possible process gentle. This object is achieved by a device with the features of claim 1.

Advantageous developments of the invention are defined by the features and feature combinations of the subclaims.

The invention is based on the fact that controlled condensation of the monomers takes place within a condensation zone. For this purpose, the condensation device is formed by a coaxial with the spinneret condensation ring, which is connected to the temperature control with a contact surface with the cooling device. Thus, the condensation ring can be conditioned accordingly in order to accommodate the condensed monomers as a deposit can. An influence on the spinning process is avoided as far as possible since the condensation ring only has to have low temperature differences compared to the spinning environment.

In order to obtain the most uniform possible absorption and binding of the monomers when using round spinning nozzles, the development of the invention is preferably carried out, in which the cooling device below the spinneret has a cooling cylinder with gas-permeable cylinder wall, which is arranged within a pressure chamber and in which the contact surface of the Condensation ring is associated with a front end of the cooling cylinder. Thus, the condensation ring is uniformly tempered over the entire circumferential contact surface.

The tempering of the condensation ring by the cooling device can be further improved by the condensation ring on a Bottom has a Temperierkragen, which projects with a free end in the cooling zone of the cooling device.

When using a cooling cylinder within the cooling zone, the development of the invention is provided, in which the Temperierkragen is concentric with the cooling cylinder of the cooling device and protrudes into the front end of the cooling cylinder. Thus, the cooling air can be advantageously used within the cooling zone to cool the tempering collar and thus the condensation ring.

In order to keep the monomers and oligomers out of the spinning process and to pick them up safely, the condensation ring is preferably designed with a circumferential collecting groove, which is kept open in relation to the condensation zone.

Thus, the collecting groove of the condensation ring is preferably formed between a vertically oriented outer annular collar and a parallel to the outer annular collar circumferential smaller inner annular collar. Since the surfaces of the condensation ring must be freed at regular intervals from the deposits and accumulations of condensed monomers, the development of the invention is particularly advantageous, in which the condensation ring is interchangeably connected to the cooling device, the height adjustable between an operating position and a War- is. This replacement of the condensation ring is fast and easy to carry out. Thus, the condensation ring can advantageously be fastened with the tempering collar through a plug connection at the open front end of the cooling cylinder. Alternatively, however, it is also possible to clean the condensation ring by simply wiping. In this case, materials or surfaces of the condensation ring are preferably selected, which allow easy cleaning. In addition, a specific temperature range can be ensured by selecting the material.

Alternatively, however, it is also possible to carry out an active heating of the condensation ring in order to be able to adapt the process conditions occurring in the cooling system in a targeted manner. Thus, the condensation rate for condensing the monomers can be improved by a certain temperature gradient.

Since the synthetic threads are usually produced with a plurality of spinnerets on a spinning beam, the development according to the invention is provided, in which a plurality of spinnerets are held on the spinning bar and in which each spinneret is assigned one of several condensation rings.

The temperature of the condensation rings is preferably carried out by a plurality of gas-permeable cooling cylinder, which are arranged within a pressure chamber and associated with their free ends the contact surfaces of the condensation rings. In that regard, uniform conditions for tempering the condensation rings are achieved in the individual spinning positions.

The invention will now be explained in more detail below with reference to some embodiments of the device according to the invention with reference to the accompanying figures. They show:

Fig. 1 shows schematically a cross-sectional view of a first embodiment of the device according to the invention

Fig. 2 shows schematically a cross-sectional view of another embodiment of the device according to the invention

Fig. 3 shows schematically a cross-sectional view of another embodiment of the device according to the invention in Fig. 1, a first embodiment of the apparatus according to the invention for melt spinning and cooling of filaments is shown schematically in a cross-sectional view. In Fig. 1, only the essential device for the invention are shown steep, since the basic structure of such devices is generally well known.

The first exemplary embodiment of the device according to the invention for melt-spinning and cooling filament strands has a spinneret 2 on an underside of a heated spinneret 1. The spinneret 2 is coupled via a melt line 17 with a spinning pump, not shown here. The spin pump generates a melt stream of a polymer, for example polyamide or polypropylene, which is supplied under pressure to the spinneret 2. The spinneret 2 has on its underside a nozzle plate, not shown here, with a multiplicity of nozzle openings, from which the polymer melt is extruded into fine filament strands.

Below the spinning beam 1, a cooling device 5 is arranged, which has a cooling zone 6 for cooling the freshly extruded filaments. For this purpose, the cooling zone 6 extends directly vertically below the spinneret 2.

In this exemplary embodiment, the cooling device 5 has a blowing chamber 9, which interacts with a pressure chamber 10 via a laterally arranged blowing wall 11. The pressure chamber 10 is connected via an air supply channel 26 with a cooling air source, not shown here. The blow chamber 10 forms the cooling zone 6, which has yarn passage openings 25 in the region of the spinneret 2 for guiding the filament strands.

At the top of the cooling device 5, a condensation device 3 is arranged between the spinneret 2 and the cooling zone 6, which forms a condensation zone 4. The condensation device 3 is formed by a condensation ring 7, which is held concentrically to the spinneret 2 between the cooling device 5 and the spinning beam 1.

The condensation ring 7 is supported via an outer annular collar 14 with respect to the spinning beam 1 and an upper side 28 of the blowing chamber 9. Between the free end of the vertically aligned outer annular collar 14 and the spinning beam 1, an insulating member 16 is provided. The condensation ring 7 is U-shaped in profile, wherein parallel to the outer ring collar 14, a smaller inner annular collar 15 is formed and forms a collecting groove 13 between them. The groove bottom of the collecting groove 13 forms a contact surface 8 with respect to the upper side 28 of the blow chamber 9. The contact surface 8 of the condensation ring 7 abuts directly against a wall of the blow chamber 9 for heat transfer. In addition, an opposing tempering collar 12 is provided on the inner annular collar 15 formed, which projects into the yarn passage opening 25 of the blast chamber 9 and extends with a free end to the cooling zone 6. Thus, the free end of the Temperierkragens 12 can be cooled within the cooling zone 6 by a cooling air.

In operation, the condensation ring 7 is cooled via the cooling device 5 to a temperature level which promotes condensation and deposition of the volatiles released in the extrusion of the filaments, in particular of the monomers. In that regard, the directly below the spinneret 2 resulting monomers and oligomers are taken directly from the condensation ring 7 in operation. The condensed monomers can advantageously be absorbed uniformly over the entire cross-section of the spinneret 2 by the condensation ring 7. The free space formed by the condensation ring 7 immediately below the spinneret 2 ensures that the monomers move out of the filament assembly due to the temperature difference and are absorbed by the walls of the annular collars 14 and 15 and the collecting groove 13 of the condensation ring 7. The exemplary embodiment shown in FIG. 1 is particularly suitable for devices in which the cooling device generates a transverse cooling air flow for cooling the filament. In principle, however, cooling device are known in which a radially generated from outside to inside cooling air flow is used to cool the filaments. Such an embodiment is shown in FIG. In Fig. 2, a further embodiment of the device according to the invention is shown in a cross-sectional view, in turn, only the essential device for the invention are shown steep. Compared to the previous embodiment, the cooling device 5, a cooling cylinder 18 which forms the cooling zone 6 in its interior. The cooling cylinder 18 has a gas-permeable cylinder wall, which could be formed for example as a double wall of a perforated plate and a metal mesh. The cooling cylinder 18 is disposed within an upper pressure chamber 19, which is coupled at the lower end via a perforated plate 24 with a lower pressure chamber 20. The lower pressure chamber 20 is penetrated in a coaxial extension to the cooling cylinder 18 by a pipe socket 23, wherein the pipe socket 23 and the cooling cylinder 18 each form a yarn passage opening 25 through the upper pressure chamber 19 and the lower pressure chamber 20. The lower pressure chamber 20 is coupled via an air supply channel 26 with a cooling air source, not shown here.

Between the cooling device 5 and a spinning beam 1, a condensation device 3 is arranged. The condensation device 3 is also formed in this case by a condensation ring 7, which is formed in its cross-sectional shape identical to the aforementioned embodiment. The condensation ring 7 is supported by a contact surface 8 directly at a front end 21 of the cooling cylinder 18. On the opposite underside of the spinning beam 1, the free end of the outer annular collar 14 is located on the insulating element 16. In that regard, the condensation ring forms 7 a condensation zone 4 immediately below the spinneret 2. Between the insulating member 16 and the upper pressure chamber 19, a sealing element 22 is provided concentrically to the condensation ring 7, which is held at the top of the pressure chamber 19.

For cooling the condensation ring 7, a tempering collar 12 is furthermore provided, which protrudes into the interior of the cooling cylinder 18. The Temperierkragen 12 is formed on the inner collar 15 of the condensation ring 7 and is cooled at the free end of the cooling zone 6. The condensation of the condensation ring 7 thus takes place via the cooling device 5. Since the condensation ring 7 is separated from the spinning beam 1 by an insulating element 16, a temperature level which promotes the condensation of the monomers is reached at the condensation ring 7. The illustrated in Fig. 2 embodiment of the apparatus according to the invention for melt spinning and cooling of filament strands is in its function substantially identical to the aforementioned embodiment. Only the cooling air flow is generated in the embodiment of FIG. 2 by the gas-permeable cooling cylinder, which directs a cooling air from the upper pressure chamber 19 from the outside into the interior of the cooling zone 6. For this purpose, the cooling air is introduced via the air supply channel 26 into the lower pressure chamber 20 and passes there via the perforated plate 24 into the upper pressure chamber 19. This makes it possible to achieve a uniform distribution of the cooling air in the upper pressure chamber 19.

In the production of synthetic threads, these are usually produced in parallel to each other in parallel alongside one another within a spinning position. In this respect, heated spinning beams are used, which are at their Un- terseite wear a group of spinnerets. In FIG. 3, such an exemplary embodiment is shown schematically in a cross-sectional view.

In the exemplary embodiment illustrated in FIG. 3, a plurality of spinnerets 2 are held next to one another in a row-like arrangement on a spinning bar 1. The spinnerets 2 are connected within the spinneret 1 by a plurality of melt lines 17 with a spinning pump 29. The spinning pump 29 is driven by a pump drive, wherein the spinning pump 29 has a separate conveying means for each spinneret 2. The spinning pump 29 is connected via a melt inlet 30 with a melt source, not shown here. The spinning beam 1 is designed to be heated, so that the spinnerets 2, the melt line 17 and the spinning pump 29 are heated. The spinning beam 1 is assigned to the bottom of a condensation device 3 and a cooling device 5. The condensation device 3 is formed by a plurality of condensation rings 7, which are arranged distributed on the spinnerets 2. In that regard, the structure of the condensation device 3 is identical to the embodiment of FIG. 2, so that at this point no further explanation and reference is made to the preceding description.

The cooling device 5 is executed in this embodiment, identical to the embodiment of FIG. 2, wherein within the upper pressure chamber 19 per spinneret 2 each one of a plurality of cooling cylinders 18 are arranged. Accordingly, the lower pressure chamber 20 per cooling cylinder 18 has one of a plurality of pipe sockets 23, which together with the cooling cylinders 17 per spinneret form a yarn passage opening 25.

Between the condensation device 3 and the spinning beam 1, an insulating member 16 is provided to isolate the condensation rings 7 relative to the heated spinning beam 1.

In this embodiment, in addition to the sealing of the cooling device 5 and the condensation device 3 relative to the environment between the insulating member 16 and the upper pressure chamber 19, a sealing element 22 is arranged. The sealing element 22 could in this case be plate-shaped, which in each case has a cutout per condensation ring 7. On both sides of the pressure chambers 19 and 20, two lifting cylinders 27.1 and 27.2 are provided to adjust the cooling device 5 between an operating position (as shown) in a waiting position. In the waiting position, the cooling device 5 is held at a distance from the spinning beam 1, so that the condensation rings 7 of the condensation devices 3 are open for cleaning. In this embodiment, it is even possible to replace the condensation rings, as a simple plug connection can be realized via the tempering collar.

The function of the embodiment according to FIG. 3 per spinneret is identical to the exemplary embodiment according to FIG. 2, so that no further explanation is made at this point and reference is made to the aforementioned description. In the embodiments illustrated in FIGS. 1 to 3, the condensation device 3 and in particular the shape of the condensation ring 7 is exemplary. It is essential here that the condensation ring is formed on the one hand from a thermally conductive material and on the other hand has a shape for receiving the condensed monomers. In that regard, the inventive device for melt spinning and cooling of filament strands is particularly suitable for producing threads of polyamide or fibers of polypropylene.

Dedicated sign

1 spinning beam

2 spinneret

3 condensation device

4 condensation zone

5 cooling device

6 cooling zone

7 condensation ring

8 contact surface

9 blow chamber

10 pressure chamber

11 blowing wall

12 tempering collar

13 collecting well

14 outer ring collar

15 inner ring collar

16 insulating element

17 Melting line

18 cooling cylinders

19 upper pressure chamber

20 lower pressure chamber

21 front end cooling cylinder

22 sealing element

23 pipe socket

24 perforated plate

25 thread passage opening

26 air supply duct 27.1, 27.2 lifting cylinder

28 top blow chamber

29 spinning pump

30 melt feed

Claims

claims

1. An apparatus for spinning and cooling of filament strands, comprising a spinneret (2) arranged on a spinning beam (1) with a cooling device (5) arranged below the spinneret (2), which has a cooling zone (6) beneath the spinneret (9) ) and with a condensation device (3) for receiving condensed monomers which forms a condensation zone (4) between the spinneret (2) and the cooling device (5), characterized in that the condensation device (3) is coaxial with the spinneret (2) arranged condensation ring (7) is formed, which is connected to the temperature control with a contact surface (8) with the cooling device (5).

2. Apparatus according to claim 1, characterized in that the cooling device (5) below the spinneret (2) has a cooling cylinder (18) with a gas-permeable cylinder wall, which is arranged within a pressure chamber (19), and that the contact surface (8). of the condensation ring (7) is associated with a front end (21) of the cooling cylinder (8).

3. Device according to claim 1 or 2, characterized in that the condensation ring (7) on its underside a Temperierkragen (12) which projects with a free end in the cooling zone (6) of the Abkühlvor- direction (5).

4. Apparatus according to claim 3, characterized in that the tempering collar (12) concentric with the cooling cylinder (18) of the cooling Device (5) is formed and projects into the front end (21) of the cooling cylinder (18).

5. Device according to one of claims 1 to 4, characterized marked, that the condensation ring (7) has a relation to the condensation zone (4) open circumferential collecting groove (13).

6. The device according to claim 5, characterized in that the collecting groove (13) between a vertically aligned outer Ringkra- gene (14) and a parallel to the outer annular collar (14) encircling smaller inner annular collar (15) is formed.

7. Device according to one of claims 1 to 6, characterized in that the condensation ring (7) interchangeable with the Abkühlvor- direction (5) is connected, wherein the cooling device (5) is height adjustable between an operating position and a waiting position.

8. Device according to one of claims 1 to 7, characterized in that the condensation ring (7) is designed to be heated.

9. Device according to one of claims 1 to 8, characterized in that on the spinning beam (1) a plurality of spinnerets (2) are held and that each spinneret (2) is associated with one of a plurality of condensation rings (7).

10. Apparatus according to claim 9, characterized in that the cooling device (5) within the pressure chamber (19) has a plurality of cooling cylinders (18) with the free front ends (21) the contact surfaces (8) of the condensation rings (7 ) assigned.