YARNS AND METHOD FOR ADAPTING A DEVICE FOR THE PRODUCTION OF YARNS

This invention relates to a device for the production of yarns, comprising at least two extruders with one or more spinnerets per extruder for producing filaments wherein the one or more spinnerets per extruder are provided for grouping the filaments produced with the aid of this extruder into several filament bundles, cooling means for cooling the filaments produced with the aid of the extruders and combining means for bringing together several filament bundles in order to produce yarns from the assembled filament bundles.

In addition, this invention relates to a method for the production of yarns with the aid of such a device and a method for adapting a device for the production of yarns to a device according to this invention.

Such devices are described and depicted for example in DE 10 2005 35 43 Al, CN 102628199 A, US 6,406,650 B l and EP 0 924 321 Al.

With the help of the extruders of such a device, separate filaments are typically formed from a thermoplastic material such as polypropylene, polyester or polyamide. The thermoplastic material melted in the extruder is pressed through several spinnerets, these spinnerets being provided with several perforations for melt- spinning the filaments. Thus, one or more bundles of such filaments are formed per spinneret. Various such filament bundles are joined together to form a multifilament yarn which is rolled up onto a bobbin, typically after one or more further treatment steps.

It is known how to use such devices with, for example, three extruders, placing in each extruder plastic granules with different properties such as a different colour, for example, and then bringing together filament bundles coming from the different extruders in order to make one yarn with three different colours (tricolour yarn). With two different colours, a bicolour yarn can be made. In general, with several colours multicolour yarns can be produced. It is also known how to bring several filament bundles of the same colour together with such devices to produce a so- called monocolour yarn. Multicolour and monocolour yarns are typically produced on different devices of this kind. When changing colours and/or when switching between multicolour and monocolour yarns with the same device, this device typically needs to be cleaned entirely and process settings need to be adapted, which entails long switchover times.

In order to simplify the switching between tricolour and monocolour yarns, it has been proposed in US 6,406,650 B l and EP 0 924 321 Al to add a distributing system to such a device between the extruders and the spinnerets. When the distributing system is moved, the supply of molten plastic between the extruders and the different spinnerets is redistributed. The switching between tricolour and monocolour yarns still requires however a long machine standstill, since at least the spinnerets need to be cleaned each time.

The goal of this invention is to simplify the switching between the production of different kinds of yarns, such as monocolour yarns and yarns of different colours (multicolour yarns), with the same device, so that shorter machine standstills are required for such a switchover.

This goal of the invention is achieved in the first place by providing a device for the production of yarns, comprising:

- at least two extruders with one or more spinnerets for producing filaments, wherein the one or more spinnerets per extruder are provided for grouping the filaments produced with the aid of this extruder into several filament bundles;

cooling means for cooling the filaments produced with the aid of the extruders;

- combining means for bringing together several filament bundles in order to produce yarns from the assembled filament bundles;

and repositioning means which are provided for placement after the cooling means, in the direction of flow of the filaments in the device, and which:

o in a first use are provided in order to leave unchanged bringing together the filament bundles with the aid of the combining means in order to produce yarns from the filament bundles so assembled;

o and in a second use are provided to rearrange the filament bundles so that differently assembled filament bundles are formed in order to produce yarns from the differently assembled filament bundles. With the help of such repositioning means, different yarn bundle combinations can be produced in a simple manner. The filament bundles are repositioned after extruding and melt-spinning the filaments with the help of these repositioning means in order to switch between the production of yarns from filament bundles that are assembled in a first manner, on the one hand, and the production of yarns from filament bundles that are assembled in a second manner, on the other hand. In this way, when switching between the production of different types of yarns the extruders and/or the spinnerets do not have to be constantly cleaned, so that the switchover times can be greatly limited. Only when the characteristics of the plastic granules of one or more of the extruders are being changed it may be necessary to clean these one or more extruders and the accompanying spinnerets.

The filament bundles are swapped after the filaments have already been formed and cooled, so that the following parts of the device are little if at all soiled by these filament bundles and little or no cleaning of parts of the device is necessary when switching between the production of different types of yarns. In principle, such devices may continue to operate without machine standstills during the switching, so that at most a few bobbins of produced yarns will be lost.

More specifically, the repositioning means of a device according to this invention may comprise per filament bundle a first-use guide element for guiding this filament bundle in the first use and a second-use guide element for guiding o this filament bundle in the second use, wherein this first-use guide element and this second-use guide element are provided to be mutually interchangeable. The known devices always contain one or more such guide elements. These can now be provided to be easily interchangeable for the first use and the second use so that a particularly simple solution for the said problem is achieved in this way.

In such a simple embodiment, the first-use guide elements can be part of a first-use guide body and the second-use guide elements can be part of a second-use guide body, wherein the first guide body and the second guide body are mutually interchangeable for the first use and the second use. Alternatively, a device according to this invention may comprise, per filament bundle, a guide element for guiding this filament bundle, wherein the repositioning means comprise displacement means for moving these guide elements between a first position for the first use and a second position for the second use.

The known devices always comprise one or more such guide elements. In practice, such displacement means for moving such guide elements between different positions may be provided to be simple and compact, so that a particularly simple solution for the said problem is achieved in this way. Even more specifically, the said guide elements may be part of the said combining means of a device according to this invention.

In a particular embodiment, the repositioning means may comprise driving means for automatic driving the displacement means. Alternatively or additionally, such displacement means may also be provided so that they can be moved in purely mechanical manner.

In one simple embodiment of a device according to this invention, the guide elements of said filament bundles of a first said extruder form first guide elements which are mutually coupled for simultaneous moving these first guide elements with the aid of the displacement means.

Preferably, in such an embodiment, the guide elements of said filament bundles of a second said extruder form second guide elements, which are mutually coupled for simultaneous moving these second guide elements with the aid of the displacement means.

Even more preferably, in such an embodiment the guide elements of said filament bundles of a third said extruder form third guide elements, which are secured on a base body, wherein the first guide elements are secured to a first coupling element which is movable in regard to the base body and wherein the second guide elements are secured to a second coupling element which is movable in regard to the base body, wherein the first coupling element is movable in regard to the second coupling element. More specifically, the base body of such an embodiment may be a base plate, which is provided with perforations, wherein the first coupling element is a first coupling plate, on which the first guide elements are secured with the aid of mounting bars, wherein these mounting bars are fitted so as to be movable through said perforations, for the movable placement of the first coupling plate with respect to the base plate, and wherein the second coupling element is a second coupling plate, which is provided with perforations, and on which the second guide elements are secured with the aid of mounting bars, wherein these mounting bars of the second guide elements are fitted so as to be movable through said perforations in the base plate, for the movable placement of the second coupling plate with respect to the base plate, and wherein the mounting bars of the first guide elements are fitted so as to be movable through said perforations in the second coupling plate for the movable placement of the first coupling plate with respect to the second coupling plate. Alternatively or additionally, the displacement means of a device according to this invention may be provided for the individual movement of each guide element.

In one specific embodiment of a device according to this invention, the combining means may be provided for bringing together several filament bundles with filaments of different extruders and the repositioning means in the second use can be provided for rearranging the filament bundles into differently assembled filament bundles with several filament bundles from the same extruder.

In an alternative specific embodiment, the combining means may be provided for bringing together several filament bundles with filaments of the same extruder and the repositioning means in the second use can be provided for rearranging of filament bundles into differently assembled filament bundles with filaments from different extruders.

Preferably, a device according to this invention also comprises detection means for detecting the assembled filament bundles from which a yarn produced with this device is being produced.

The repositioning means of a device according to this invention may in at least one additional use be provided to rearrange the filament bundles so that yet other assembled filament bundles are formed in order to produce yarns from the yet other assembled filament bundles.

Thus, a simple switching is possible between the production of yarns from filament bundles assembled with the aid of the combining means and from differently assembled filament bundles in a second use, and from yet other assembled filament bundles in an additional use, so that the flexibility of such a device is even further enhanced.

In addition, the object of this invention is also achieved by providing a method for the production of yarns, comprising producing filaments with the aid of at least two extruders with one or more spinnerets per extruder, grouping the filaments produced with the aid of this extruder with the one or more spinnerets per extruder into several filament bundles, cooling the filaments in the filament bundles and after cooling the filaments bringing together several filament bundles in order to produce yarns from the assembled filament bundles wherein this method involves repositioning the filament bundles after cooling of filaments in order to form differently assembled filament bundles in order to produce yarns from these differently assembled filament bundles. In one simple method according to this invention wherein the said device comprises at least one guide roller with guide ribs, which delimit guide grooves for guiding several filament bundles at a distance from each other in these guide grooves, the filament bundles can be moved from guide groove for repositioning the filament bundles.

The filament bundles may be moved manually from guide groove or they can be moved mechanically or automatically.

In one preferred method according to this invention the yarns are produced with the aid of a device according to this invention as described above.

The object of this invention is also achieved by providing a method for adapting a device for the production of yarns comprising at least two extruders with one or more spinnerets per extruder for producing filaments, wherein the one or more spinnerets per extruder are provided for grouping the filaments produced with the aid of this extruder into several filament bundles, cooling means for cooling the filaments produced with the aid of the extruders and combining means for bringing together several filament bundles in order to produce yarns from the assembled filament bundles, wherein the device is provided with repositioning means which are provided for placement after the cooling means and which:

in a first use are provided in order to leave unchanged bringing together the filament bundles with the aid of the combining means in order to produce yarns from the filament bundles so assembled;

- and in a second use are provided to rearrange the filament bundles so that differently assembled filament bundles are formed in order to produce yarns from the differently assembled filament bundles.

In this way, existing devices for the production of yarns can be converted in a simple manner to a device for the production of yarns according to this invention.

Preferably in a method according to this invention for adapting a device for the production of yarns this device is adapted into a device according to this invention as described above.

Thus, for example, the device may comprise one guide element per filament bundle for guiding this filament bundle, which is provided as a said first-use guide element or is replaced by a first-use guide element, and it can be provided with a second-use guide element per filament bundle, for guiding this filament bundle in the second use, wherein this second-use guide element is provided to be interchangeable with the first-use guide element.

Alternatively, this device may comprise, for example, one guide element per filament bundle for guiding this filament bundle and in such a method according to this invention this device is adapted to be provided with displacement means as said repositioning means for the movement of these guide elements between a first position for the first use and a second position for the second use. This invention shall now be explained more closely by means of the following detailed description of several preferred embodiments of devices for the production of yarns according to this invention. The purpose of this description is solely to give illustrative examples and to point out further advantages and features of the invention, and thus may not be interpreted as being a limitation of the area of application of the invention or of the patent rights claimed in the claims.

In this detailed description, reference shall be made by means of reference numbers to the appended drawings, in which

- figure 1 shows a portion of a first embodiment of a device for the production of yarns according to this invention in perspective view in the area of repositionable guide elements standing in their first position;

figure 2 shows the portion of the device from figure 1 in perspective view in the area of the guide elements standing in their second position;

- figure 3 represents the guide elements and displacement means of the device from figure 1 in top view with the guide elements in their first position;

figure 4 represents the guide elements and displacement means of the device from figure 1 in top view with the guide elements in their second position;

figure 5 represents schematically a device for the production of yarns according to this invention;

figure 6 represents a portion of a second embodiment of a device for the production of yarns according to this invention with a first positioning plate and a second positioning plate in front view;

figure 7 shows the first positioning plate of the device from figure 6 in perspective view;

figure 8 shows the first positioning plate of the device from figure 6 in top view;

figure 9 represents the second positioning plate of the device from figure 6 in top view.

The device (19) depicted in figures 1 to 4 and the device (19) depicted in figures 6 to 9 for the production of yarns each comprise three extruders (20), not shown, with three spinnerets (21) per extruder (20), not shown, for the production of three by three filament bundles (1, 2, 3). In figure 5 a device (19) for the production of yarns according to this invention is represented schematically, with different extruders (20) having several spinnerets (21) per extruder (20) for the production of several filament bundles (1, 2, 3). The first filament bundles (1) depicted in figures 1 to 4 are produced with the first extruder (20) and the corresponding spinnerets (21).

The second depicted filament bundles (2) are produced with the second extruder (20) and the corresponding spinnerets (21).

The third depicted filament bundles (3) are produced with the third extruder (20) and the corresponding spinnerets (21).

Each of the extruders (20) may be filled, for example, with granules of a different colour, so that these filament bundles (1, 2, 3) each comprise filaments with a respective colour.

In figures 6 to 9, the filament bundles (1) are not shown. These are also produced and delivered in the same way.

After producing the filament bundles (1, 2, 3), these are dried as shown schematically in figure 5 in a quench cabinet (22), after which they are taken via the yarn duct (23) to the unit (25) depicted in figures 1 to 4 with guide elements (4, 5, 6) or to the unit (25) depicted in figures 6 to 9 with guide elements (4, 4a, 4b, 5, 5a, 5b, 6, 6a, 6b), and are combined together with further combining means into a multifilament yarn. This multifilament yarn is then taken with the aid of guide means (24) to one or more further processing elements, such as a texturing channel (26), a cooling drum (27), heated stretching rollers (28) and intermingling (29), and is then finally wound up on bobbins in a winding unit (30). Such a device (19) typically comprises also one or more reversal rollers (24) and/or guide rollers (24) and/or guide bars (16) for intermediate guiding the filament bundles (1, 2, 3) or the multifilament yarn. Just prior to the guide elements (4, 5, 6) shown in figures 1 to 4, oil is sprayed onto the filaments formed in the depicted device (19). In the embodiment of figures 1 to 4, at the guide elements (4, 5, 6) air is blown onto the filaments in order to distribute this oil and the residual oil is captured in the collecting trough (17) and hauled away. In the embodiment of figures 6 to 9, oil is sprayed onto the formed filaments through the uppermost depicted guide elements (4, 5, 6). Just beneath these guide elements (4, 5, 6), excess oil is captured in collecting troughs (35) and hauled away. Right after the stretching rollers (28) air is blown onto the filaments to distribute the oil. In this way, the guide elements (4, 5, 6, 4a, 5a, 6a, 4b, 5b, 6b) and repositioning means (31, 32) may be designed more simply.

The depicted guide elements (4, 5, 6, 4a, 5a, 6a, 4b, 5b, 6b) comprise first guide elements (4, 4a, 4b) for guiding the first filament bundles (1), second guide elements (5, 5a, 5b) for guiding the second filament bundles (2) and third guide elements (6, 6a, 6b) for guiding the third filament bundles (3).

In the embodiment of figures 1 to 4, the third guide elements (6) are secured by means of fastening elements (18) firmly to a base plate (11), which is arranged fixedly in the device (19). Several perforations are made in the base plate (11).

The second guide elements (5) in this embodiment are secured by means of mounting bars (13) at a distance to a second coupling plate (10). The mounting bars (13) are arranged through said perforations in the base plate (11), so that the second guide elements (5) extend on the same side of the base plate (11) as the third guide elements (6) and so that the second coupling plate (10) extends on the other side of this base plate (11). The mounting bars (13) are provided to be movable and guiding in these perforations, so that the coupling plate (10) and with it also the second guide elements (5) are movable between a first position, as depicted in figures 1 and 3, and a second position, as depicted in figures 2 and 4. Several perforations are made in the coupling plate (10).

The first guide elements (4) are secured by means of mounting bars (12) at a distance to a first coupling plate (9). The mounting bars (12) are arranged through said perforations in the base plate (11) and through said perforations in the second coupling plate (10), so that the first guide elements (4) extend on the same side of the base plate (11) and the second coupling plate (10) as the second and third guide elements (5, 6) and so that the first coupling plate (9) extends on the other side of this base plate (11) and the second coupling plate (10). The mounting bars (12) are provided to be movable and guiding in these perforations, so that the coupling plate (9) and with it also the first guide elements (4) are movable between a first position, as depicted in figures 1 and 3, and a second position, as depicted in figures 2 and 4. In order to be able to move the coupling plates (9, 10) in simple manner and place them in the different positions, a corresponding operating bar (14, 15) is secured to each coupling plate (9, 10), being arranged through said corresponding perforations, so that this can be operated manually from the side of the base plate (11) where the guide elements (4, 5, 6) are positioned.

The coupling plates (9, 10), mounting bars (12, 13) and operating bars (14, 15) together form displacement means (7, 8) for moving the first guide elements (4) and the second guide elements (5).

In the first position, as depicted in figures 1 and 3, each time three filament bundles (1, 2, 3) side by side, in the order in which they appear in the figures, are brought together with the aid of these guide elements (4, 5, 6) and other combining means positioned further so as to form three tricolour yarns.

In the second position, as depicted in figures 2 and 4, the filament bundles (1, 2, 3) are moved so that three first filament bundles (1) are brought together with the combining means positioned further so as to form a first monocolour yarn, three second filament bundles (2) are brought together to form a second monocolour yarn, and three third filament bundles (3) are brought together to form a third monocolour yarn.

In the embodiment depicted in figures 6 to 9, the repositioning means (31, 32) comprise, per filament bundle (1, 2, 3), a first-use guide element (4a, 5a, 6a) for guiding this filament bundle (1, 2, 3) in the first use and a second-use guide element (4b, 5b, 6b) for guiding this filament bundle (1, 2, 3) in the second use. The different first-use guide elements (4a, 5a, 6a) for the different filament bundles (1, 2, 3) are part of the same first positioning plate (31). The second-use guide elements (4b, 5b, 6b) for the different filament bundles (1, 2, 3) are part of the same second positioning plate (32). The first positioning plate (31) and the second positioning plate (32) are provided to be mutually interchangeable. For this, these positioning plates (31, 32) can be fastened with the aid of screws (34) to a support (33). As can be seen in figure 6, this support (33) may be provided so that both positioning plates (31, 32) can be secured to it, so that the positioning plate (31, 32) which is not in use does not get lost.

For the first use, the first positioning plate (31) is secured on top of this support (33) and the second positioning plate (32) is secured sideways to this support (33), as can be seen in figure 6. Then, each time three filament bundles (1, 2, 3) side by are brought together by means of the first-use guide elements (4a, 5a, 6a) and combining means further arranged in order to form three tricolour yarns.

For the second use, the second positioning plate (32) is secured on top of the support (33) and the first positioning plate (31) is secured sideways to the support (33). The three filament bundles (1, 2, 3) are then moved by the guide elements (4, 5, 6) so that with the aid of the combining means further arranged three first filament bundles (1) are brought together in order to form a first monocolour yarn, three second filament bundles (2) are brought together in order to form a second monocolour yarn, and three third filament bundles (3) are brought together in order to form a third monocolour yarn.

The depicted guide elements (4, 5, 6, 4a, 5a, 6a, 4b, 5b, 6b) and the optional corresponding displacement means (7, 8) can be easily installed in an existing device (19) for the production of yarns, so that an existing device (19) can thus be easily converted into a device (19) for the production of yarns according to this invention.