CN113737291A

CN113737291A - Melt spinning apparatus

Info

Publication number: CN113737291A
Application number: CN202110582573.XA
Authority: CN
Inventors: S·福尔斯蒂奇; R·多曼斯; A·斯赫韦斯
Original assignee: Oerlikon Textile GmbH and Co KG
Current assignee: Oerlikon Textile GmbH and Co KG
Priority date: 2020-05-29
Filing date: 2021-05-27
Publication date: 2021-12-03
Anticipated expiration: 2041-05-27
Also published as: CN113737291B

Abstract

The invention relates to a melt spinning device for melt spinning a plurality of filaments from a polymer melt, comprising a heatable nozzle support for receiving a spinning nozzle unit. For this purpose, the nozzle support has a receptacle opening on the underside, wherein the spinning nozzle unit is held in the receptacle opening in such a way that the lower nozzle plate cup of the spinning nozzle unit is arranged offset relative to the underside of the nozzle support. In order to be able to perform effective wiping despite a deep offset, according to the invention, an adjusting mechanism is arranged on the nozzle support and/or the spinning nozzle unit, by means of which the nozzle plate can be held so as to be freely accessible for wiping.

Description

Melt spinning apparatus

Technical Field

The present invention relates to an apparatus for melt spinning a plurality of filaments from a polymer melt.

Background

An apparatus of this type for melt spinning a plurality of filaments from a polymer melt is known, for example, from DE102005049162a 1.

In the production of synthetic threads or fibers, it is common practice to supply a previously molten polymer at high pressure by means of a spinning pump to a spinning nozzle unit having a nozzle plate. The nozzle plate has a plurality of nozzle openings so that the polymer melt is extruded into the most elongated strands. The spinning nozzle unit is held by a heatable nozzle support, which has a receptacle opening on its underside for receiving the spinning nozzle unit. The spinning nozzle unit in the receptacle opening can be connected in an exchangeable manner by means of a connection adapter. The spinning nozzle unit is held in the receptacle opening in such a way that the lower nozzle plate of the spinning nozzle unit is arranged offset inward with respect to the lower side of the nozzle support. The strands that have just been extruded out of the nozzle openings of the nozzle plate can then be spun first into a plateau region, which is formed by the offset and in which no interference from downstream cooling devices has yet occurred. Such nozzle supports are also known in the industry as so-called spinning beams, since they usually accommodate and heat a number of spinning nozzle units. The manifold for guiding the polymer melt in the nozzle support is then also heated.

Depending on the type of polymer, the melt viscosity, the throughput per nozzle opening, the spinning pressure and, in particular, the nozzle plate material, material deposits occur on the nozzle plate of the spinning nozzle unit, in particular in the region of the nozzle openings. It is therefore conventional practice to clean the nozzle plate on the underside after a certain operating time. The cleaning is carried out by so-called scraping, in which deposits, in particular formed from monomers and oligomers, are scraped off from the nozzle plate surface. The wiping operation of such a nozzle plate may be performed manually by a so-called wiping robot or automatically. However, a deep offset of the spinning nozzle unit relative to the underside of the nozzle support is particularly disadvantageous here, since the scraping tool has to be guided into the receptacle opening.

In the known apparatus for melt-spinning a plurality of threads, the depth offset between the underside of the nozzle support and the nozzle plate of the spinning nozzle unit can be designed to be variable when assembling the spinning nozzle unit in the receptacle opening. The spinning nozzle unit can thus be held at different depth offsets in the receptacle opening during operation. However, the small depth offset has the disadvantage that there is only a short plateau region for the filaments to be spun below the nozzle plate. Furthermore, the penetration of the receptacle opening by the scraping tool into the depth offset requires the spinning pump to be switched off, as a result of which the continuous flow of the melt in the spinning nozzle unit is interrupted.

Disclosure of Invention

The object of the present invention is to improve such a device for melt spinning a plurality of threads such that an efficient scraping of the nozzle plate on the spinning nozzle unit can be achieved without interrupting the extrusion.

According to the invention, this object is achieved by an adjusting mechanism provided on the nozzle support and/or the spinning nozzle unit, by means of which the nozzle plate can be held in a freely accessible manner for wiping.

The present invention is distinguished from the inherent idea that the path of the polymer melt to the nozzle plate must be kept uniform in order not to obtain differences in residence time when supplying the polymer melt. Since it is not necessary to maintain consistent operating conditions during the scraping cycle, the inventors have recognized that the operating conditions for directing and for temperature controlling the polymer melt are variable during scraping. In this connection, adjusting means are arranged on the nozzle carrier and/or the spinning nozzle unit, by means of which adjusting means the nozzle plate can be held so as to be freely accessible for scraping. As a result, the nozzle plate can be held on the underside of the nozzle support without a deep offset, so that a linear wiping movement of the wiping tool can be carried out. Without interrupting the extrusion process. The wiping tool can thus be moved into a position laterally beside the spinning nozzle unit in order to subsequently clean the underside of the nozzle plate by means of a linear wiping movement.

Different variations of this embodiment of the adjustment mechanism are possible in order to compensate for and span nozzle plate depth misalignment relative to the underside of the nozzle support. In a first alternative embodiment, the adjusting mechanism between the nozzle support and the spinning nozzle unit has a telescopic connection adapter, by means of which the spinning nozzle unit can be guided in a reciprocating manner in the receptacle opening of the nozzle support between a melt-spinning operating position and a wiping position. The step-over of the depth offset between the spinning nozzle unit and the nozzle support can advantageously be bridged by a telescopic adapter between the spinning nozzle unit and the nozzle support.

In principle, however, it is also possible to arrange the spinning nozzle unit in the receptacle housing of the nozzle carrier in such a way that the nozzle plate ends flush with the underside of the receptacle housing. The receptacle housing is movably held in the nozzle holder and can be guided in a reciprocating manner with a deep offset between a melt-spinning operating position and a wiping position. In this case, however, there is a need for flexible arrangement of the main lines for feeding the polymer melt to the spinning nozzle unit.

In a particularly advantageous variant of the invention, the adjusting mechanism has a separate heating element which is arranged on the underside of the nozzle support and surrounds at least the part of the spinning nozzle unit which projects from the receptacle opening and is held detachably or movably on the nozzle support. Both a stationary connector and a stationary main line can be used in this way. The individual heating elements here form the underside of the nozzle carrier and thus the depth offset with respect to the spinning nozzle unit. At the same time, such a heating element can be used as a so-called afterheater, which allows in particular a delayed cooling of the filaments. As an alternative or in addition to the heating element, the adjusting mechanism can have a separate heat-insulating element which is arranged on the underside of the nozzle support and surrounds at least the part of the spinning nozzle unit projecting from the receptacle opening and is held detachably or movably on the nozzle support. The heating element may be designed as a heating beam. The insulating elements can be designed in the shape of beams.

In the case of a heating element which is preferably limited to a spinning nozzle unit, the development of the invention is preferably used in which the heating element is of annular design and/or can be removed from the nozzle support for scraping purposes. Alternatively or additionally, the heat-insulating element can be configured in a ring shape and/or can be removed from the nozzle support for scraping.

Alternatively, however, according to an advantageous development of the invention, the heating element can also be held on the nozzle holder at a distance from the nozzle holder in the operating position, and the heating element and/or the heat-insulating element can be configured so as to be displaceable toward the nozzle holder for scraping. In this way, the heating element can be movably held on the nozzle support and adjusted only briefly. The spacing of the heating element from the nozzle carrier is designed here to be greater than the depth offset between the underside of the heating element and the spinning nozzle unit. In this way it is ensured that the underside of the spinning nozzle protrudes by moving the heating element towards the nozzle support.

In order to ensure temperature control of the spinning nozzle unit, in particular during operation, despite the spacing between the nozzle support and the heating element, it is provided that an electrical heating rod for temperature control of the spinning nozzle unit is arranged between the nozzle support and the heating element, concentrically with the receptacle opening. Because of the electric heating strip, the working temperature in the spinning nozzle can be kept.

In order to achieve automation, the invention preferably provides that the adjusting mechanism has at least one adjusting actuator which can be activated before and after the nozzle plate is scraped against the spinning nozzle unit. Thus, the nozzle plate exposure and wiping operations can be automated. Hydraulic or pneumatic or electric means, for example in the form of a spindle drive, can be used as adjustment actuator.

Since a plurality of spinning nozzle units are usually held simultaneously on the nozzle plate during the production of the synthetic thread, the development of the invention is particularly advantageous in that the nozzle support has a plurality of receptacle openings on the underside for receiving a plurality of spinning nozzle units, and in that the adjusting mechanism comprises at least one group of spinning nozzle units for releasing the nozzle plate. In this way, for example, a congruent heating element can be arranged on the underside of the nozzle holder, said heating element having a cutout that corresponds concentrically to the receptacle opening.

Here, the receptacle opening and the cut-out can have any shape, so that a round, oval or even rectangular spinning nozzle unit can be used. It is essential here that the adjusting mechanism is offset in depth for the scraping on each spinning nozzle unit.

Drawings

The invention will be explained in more detail below with reference to the drawing and by means of a number of embodiments of a melt spinning apparatus according to the invention, in which:

FIG. 1.1 schematically shows a cross-sectional view of a first embodiment of a melt spinning apparatus according to the present invention;

fig. 1.2 schematically shows the embodiment of fig. 1.1 in a scraping position;

FIG. 2 schematically shows a cross-sectional view of another embodiment of a meltspinning apparatus according to the invention;

FIG. 3 schematically shows a cross-sectional view of another embodiment of a meltspinning apparatus according to the invention;

FIG. 4.1 schematically shows a view of another embodiment of a melt spinning apparatus according to the present invention; and

fig. 4.2 schematically shows the embodiment of fig. 4.1 in a scraping position.

Detailed Description

A first embodiment of an apparatus for melt spinning a plurality of filaments from a polymer melt according to the invention is schematically illustrated in the cross-sectional views of fig. 1.1 and 1.2. Fig. 1.1 shows the device in the working position, and fig. 1.2 shows the device in the scraping position. The following description applies to both figures unless any one of them is explicitly mentioned.

This exemplary embodiment has a nozzle support 1 which has a receptacle opening 4 on the underside 3. The receptacle opening 4 projects through the receptacle wall 6 into the interior of the nozzle holder 1. The nozzle support 1 is designed as a hollow body and has a heating chamber 7. The heating chamber 7 is typically heated by a heat transfer medium.

A screw joint 9 on which the spinning nozzle unit 2 is detachably arranged is held in the receptacle opening 4. The spinning nozzle unit 2, which is also referred to in the industry as a so-called spinning nozzle assembly, is shown here only in the component parts relevant to the invention. Spinning nozzle units 2 of this type are known and are described in more detail, for example, in DE102014000305a 1. The publications cited are hereby incorporated by reference.

The spinning nozzle unit 2 has a nozzle plate 8 with a plurality of nozzle openings 8.1 for extruding a polymer melt to form a plurality of filament strands. The nozzle plate 8 is held in the nozzle housing 10. The nozzle housing 10 has a connecting thread 20 at the end facing the screw connection 9, by means of which the spinning nozzle unit 2 is screwed onto the screw connection 9.

The screw joint 9 is coupled to an adjusting mechanism 11, by means of which the spinning nozzle unit 2 in the receptacle opening 4 can be guided in a reciprocating motion. In this embodiment, the adjusting mechanism 11 is formed by a telescopic adapter 16, which is arranged between the nozzle support 1 and the spinning nozzle unit 2. A telescopic adapter 16 in the nozzle support 1 is connected to the stationary melt line 12 and has a continuous melt duct 21, which also passes through the screw adapter 9. The melt line 21 opens into the spinning nozzle unit 2.

The telescopic adapter 16 is not explained in detail in terms of its construction and has a telescopic construction in order to displace the screw adapter 9 and the spinning nozzle unit 2 within the receptacle opening 4.

In figure 1.1 the telescopic adaptor 16 is shown in a retracted state.

This state of the spinning nozzle unit 2 represents an operating state. The nozzle plate 8 of the spinning nozzle unit 2 is held in this case with an internal offset relative to the underside 3 of the nozzle support 1. The internal offset is referred to as depth offset and is denoted by reference numeral 5 in fig. 1.1.

In order to clean deposits from the lower face of the nozzle plate 8 after a certain operating time, the adjusting mechanism 11 is activated by an actuator, not shown in detail here, so that the telescopic joint 16 pushes the spinning nozzle unit 2 out of the receptacle opening 4, so that the lower face of the nozzle plate 8 is freely accessible. This situation is shown in fig. 1.2. The nozzle plate 8 of the spinning nozzle unit 2 is now freely accessible for scraping, whereby the scraping tool can be guided by a simple linear movement. There is no need to interrupt the extrusion of the filament strand, since the scraping tool can be guided transversely onto the spinning nozzle unit 2 and does not have to interfere with the depth offset.

Various adjustment mechanisms 11 can be implemented to allow the nozzle plate 8 of the spinning nozzle unit 2 on the nozzle support 1 to be freely accessible. In this way, a further embodiment of the apparatus according to the invention for melt spinning a plurality of filaments is schematically illustrated in the cross-sectional view of fig. 2. The construction according to fig. 2 of the spinning nozzle unit 2 and the nozzle plate 1 is substantially identical to the embodiment according to fig. 1.1, so that only the differences are explained here, and reference is made to the preceding description.

In the exemplary embodiment shown in fig. 2, the receptacle opening 4 is integrated into a receptacle housing 13 on the underside 3 of the nozzle support 1. The receptacle housing 13 extends into the nozzle holder 1 and is held on the nozzle holder 1 in a displaceable manner. For this purpose, a receptacle housing 13 in the nozzle holder 1 is connected to the flexible fuse line 12. The melt line 12 leads into a connection adapter 17, which is connected to the screw joint 9. The nozzle housing 10 of the spinning nozzle unit 2 is held on the screw joint 9.

The spinning nozzle unit 2 is arranged in the receiving housing 13 in such a way that the nozzle plate 8 is held in the lower region of the receiving housing 13 flush with the underside of the receiving housing 13 or protrudes slightly therefrom. In order to scrape the nozzle plate 8, the receiving housing 13 in the nozzle holder 1 is therefore moved downwards, so that the receiving housing 13 and the nozzle plate 8 are held in position projecting from the underside 3 of the nozzle holder 1. This situation is shown in fig. 2. In operation, the receiving housing 13 with the spinning nozzle unit 2 is moved back into the nozzle holder 1, so that the required depth offset is produced on the underside 3 of the nozzle holder 1. The adjusting mechanism 11 may have an adjusting actuator in the form of an electric, pneumatic or hydraulic linear drive.

Fig. 3 shows a further variant of the adjusting mechanism. Fig. 3 shows schematically in a sectional view a further embodiment of the apparatus according to the invention for melt-spinning a plurality of filaments. The arrangement of the nozzle carrier 1 and the spinning nozzle unit 2 is also substantially the same here as in the exemplary embodiment according to fig. 1.1, so that only the differences will be explained here, and reference is made to the preceding description.

In the exemplary embodiment shown in fig. 3, the spinning nozzle unit 2 is held in the receptacle opening 4 of the nozzle holder 1 in such a way that the nozzle plate 8 of the spinning nozzle unit 2 projects over the underside 3 of the nozzle holder 1. As the adjusting mechanism 11, a movable heating element 14 is provided, which in this embodiment is formed by a heating ring 22, which surrounds the protruding region of the spinning nozzle unit 2 on the underside 3 of the nozzle support 1. In this case, a depth offset 5 for the spun thread spun out of the nozzle plate 8 is formed by the heating ring 22. The heating ring 22 is detachably connected to the nozzle holder 1. In order to scrape the nozzle plate 8, the heating ring 22 can be removed from the underside 3 of the nozzle support 1. The nozzle plate 8 of the spinning nozzle unit 2 on the nozzle support 1 is thus freely accessible. The regulating mechanism is particularly suitable for melt spinning processes in which it is necessary to spin the spun filaments into a relatively long post-heating zone. In this way, a large depth offset can also be produced by heating the ring.

In the embodiments of the apparatus for melt-spinning a plurality of threads according to the invention shown so far, a nozzle holder 1 for receiving a spinning nozzle unit 2 is shown. In principle, however, such a nozzle support 1 has a plurality of spinning nozzle units which are held in place in one or more rows side by side on the underside of the nozzle support. The nozzle support is therefore preferably also referred to in the industry as a so-called spinning beam. The previously illustrated embodiments are therefore also suitable for nozzle holders with a plurality of receptacle openings. In this respect, the adjusting mechanism is extended to one or more spinning nozzle units according to an embodiment variant.

Fig. 4.1 and 4.2 show a further example of a further alternative embodiment of the device according to the invention for melt-spinning a plurality of threads, having an adjusting mechanism 11. Fig. 4.1 shows the exemplary embodiment with a plurality of spinning nozzle units 2.1 to 2.6 in the operating position for melt spinning a plurality of threads, and fig. 4.2 shows the state in the wiping position. The following description applies to both figures unless any of them is explicitly mentioned.

The exemplary embodiment according to fig. 4.1 to 4.2 shows a beam-like nozzle carrier 1, which carries a plurality of spinning nozzle units on a lower side 3. The number of spinning nozzle units exemplarily shown here is six units. The receptacles and connectors of the spinning nozzle units 2.1 to 2.6 can be realized in a corresponding manner to the exemplary embodiment according to fig. 3. The spinning nozzle units 2.1 to 2.6 are each connected to the spinning pump 23 via a stationary melt line 12. The spinning pump 23 is realized in the form of a multi-pump in order to be able to supply each spinning nozzle unit 2.1 to 2.6 with a small partial flow of the polymer melt. The nozzle holder 1 is realized in such a way that it can be heated by means of a heat transfer medium, so that the spinning nozzle parts of the spinning nozzles 2.1 to 2.6 and the melt line 12 in the heating chamber 7 of the nozzle holder 1 are heated.

The spinning nozzle units 2.1 to 2.6 are held in a significantly protruding manner on the underside 3 of the nozzle support 1. In this case, the spinning nozzle unit 2 is heated in the lower region by a separate heating element 14. In this exemplary embodiment, the heating element 14 is formed in the form of a lower heating beam 25 which extends congruent to the nozzle support 1 and has a through-opening 24 for each spinning nozzle unit 2.1 to 2.6. The heating beam 25 can be heated internally, for example by means of a heat transfer fluid, so that the spinning nozzle units 2.1 to 2.6 can be heated in the lower region. The heating beam 25 is shown in the working position in fig. 4.1. The heating beam 25 is spaced apart from the underside 3 of the nozzle support 1, so that the spinning nozzle units 2.1 to 2.6 are held on the heating beam 25 with a depth offset 5.

In the region between the underside 3 of the nozzle support 1 and the heating beam 25, individual electrical heating strips 26 (which are held on the underside 3 of the nozzle support 1 in the form of a jacket surrounding the spinning nozzle units 2.1 to 2.6) are each assigned to the spinning nozzle units 2.1 to 2.6. In this connection, temperature control is ensured even in the case where the interval between the heating beam 25 and the nozzle holder 1 is long.

In order to scrape the spinning nozzle units 2.1 to 2.6 on the nozzle plate (not shown here), the heating beam 25 is moved in the direction of the nozzle support 1. For this purpose, the adjusting mechanism 11 has an adjusting actuator 15. In this embodiment, the adjustment actuator 15 is formed by an adjustment spindle 19 on a spindle motor 18. In this way, the heating beam 25 is held at both ends by an adjusting spindle 19 on the underside 3 of the nozzle support 1. The adjustment spindles 19 are respectively connected to spindle motors 18, so that by activating the spindle motors 18, the heating beams 25 are moved upward toward the nozzle holders 1 and expose the nozzle plates 8 of the spinning nozzle units 2. This situation is shown in fig. 4.2. Now, it is preferable that the nozzle plate 8 of the spinning nozzle unit 2 can be scraped intensively. Once scraping is completed, the heating beam 25 is returned to its working position.

The apparatus for melt spinning a plurality of filaments of the present invention is suitable for manual or automatic scraping of the spinning nozzle unit. The adjusting mechanism can be accessible to individual spinning nozzle units or groups of spinning nozzle units, so that the spinning nozzle units can be scraped individually or in groups at their nozzle plates. The extrusion operation need not be interrupted.

Claims

1. A melt-spinning device for melt-spinning a plurality of filaments from a polymer melt, having a heatable nozzle support (1) for receiving a spinning nozzle unit (2), wherein the nozzle support (1) has a receptacle opening (4) on the underside (3), and wherein the spinning nozzle unit (2) is held in the receptacle opening (4), such that a lower nozzle plate (8) of the spinning nozzle unit (2) is arranged with an internal offset (5) with respect to the lower side (3) of the nozzle carrier (1), i.e. a depth offset, characterized in that an adjusting mechanism (11) is provided on the nozzle support (1) and/or on the spinning nozzle unit (2), the nozzle plate (8) can be held freely accessible for wiping purposes by means of the adjusting mechanism (11).

2. The device according to claim 1, characterized in that the adjusting mechanism (11) between the nozzle support (1) and the spinning nozzle unit (2) has a telescopic connecting adapter (16), by means of which telescopic connecting adapter (16) the spinning nozzle unit (2) can be guided in a reciprocating manner in the receptacle opening (4) of the nozzle support (1) between a melt spinning operating position and a scraping wiping position.

3. The device according to claim 1, characterized in that the adjusting mechanism (11) has a receptacle housing (13) which, for the depth-free accommodation of the spinning nozzle unit (2), is arranged so as to be movable in the nozzle carrier (1) and can be guided in a reciprocating manner between a melt-spinning operating position and a wiping position.

4. The device according to claim 1, characterized in that the adjusting mechanism (11) has a separate heating element (14), in particular in the form of a heating beam, the heating element (14) being arranged on the underside of the nozzle support, and/or the adjusting mechanism (11) has a separate heat-insulating element which is arranged on the underside of the nozzle support and surrounds at least the part of the spinning nozzle unit (2) which projects out of the receptacle opening (4), and which is held on the nozzle support (1) in a detachable or movable manner.

5. The apparatus according to claim 4, characterized in that the heating element (14) and/or the heat insulating element is configured to be annular and removable from the nozzle support (1) for scraping purposes.

6. The apparatus according to claim 4, characterized in that the heating element (14) and/or the heat insulating element is held on the nozzle holder (1) at a distance from the nozzle holder (1) in the operating position and the heating element (14) is configured to be movable towards the nozzle holder for wiping purposes.

7. The apparatus according to claim 6, characterized in that between the nozzle support (1) and the heating element (14) and/or between the nozzle support (1) and the heat insulating element, an electrothermal strip (26) for temperature control of the spinning nozzle unit (2) is arranged concentric to the receptacle opening (4).

8. The device according to any one of claims 1 to 7, characterized in that the adjusting mechanism (11) has at least one adjusting actuator (15), the at least one adjusting actuator (15) being activatable before and after scraping of the nozzle plate (8) on the spinning nozzle unit (2).

9. The apparatus according to any of claims 1 to 8, characterized in that the nozzle carrier (1) has a plurality of receptacle openings (4) on the lower side for receiving a plurality of spinning nozzle units (2.1-2.6), and the adjusting mechanism (11) comprises at least one set of spinning nozzle units (2.1-2.6) for releasing the nozzle plate (8).