MELT CONVEYOR FOR AN EXTRUSION TOOL OF AN EXTRUSION SYSTEM, EXTRUSION TOOL, EXTRUSION SYSTEM AND METHOD FOR OPERATING AN EXTRUSION SYSTEM OF THIS TYPE

Abstract

Melt conductor (1), in particular melt distributor or melt mixer, for an extruding die (2) of an extrusion facility (3), having a melt conductor block (4) with a multi-channel system (5), the multi-channel system (5) being arranged so as to extend three-dimensionally inside the melt conductor block (4) and having at least one input (6) and at least one output (7) for polymer melt, between one input (6) and one output (7) fluidically connected to the input (6) several branchings (8) arranged in series and several levels (9a, 9b, 9c) of sub-branches (10) being formed over several levels (12a, 12b) of divided melt channels (11a, 11b), m melt channels (11a) of the a.sup.th level (12a) with x.sup.th local cross-sections and n melt channels (11b) of the b.sup.th level (12b) with y.sup.th local cross-sections being present, wherein n>m if b>a, the y.sup.th local cross-sections of the melt channels (11b) of the b.sup.th level (12b) being smaller than the x.sup.th local cross-sections of the melt channels (11a) of the a.sup.th level (12a),

and wherein in the area of the multi-channel system (5), means for at least indirectly influencing polymer melt are arranged.

Claims

1. Melt conductor, in particular melt distributor or melt mixer, for an extruding die of an extrusion facility, comprising a melt conductor block with a multi-channel system, the multi-channel system being arranged with three-dimensional extension inside the melt conductor block and having at least one input and at least one output for polymer melt, where between an input and an output fluidically connected to the input, several branchings arranged in series and several levels of sub-branches are formed over several levels of divided melt channels, m melt channels of the a.sup.th level with x.sup.th local cross-sections and n melt channels of the b.sup.th level with y.sup.th local cross-sections being present, wherein n>m if b>a, the y.sup.th local cross-sections of the melt channels of the b.sup.th level being smaller than the x.sup.th local cross-sections of the melt channels of the a.sup.th level (12a), and wherein in the designated direction of flow of the polymer melt, the melt channels of the a.sup.th level are oriented towards the input and the melt channels of the b.sup.th level towards the output such that the melt conductor acts as a melt distributor for a designated melt stream of the polymer melt, or in the designated direction of flow of the polymer melt, the melt channels of the a.sup.th level are oriented towards the output and the melt channels of the b.sup.th level towards the input, such that the melt conductor acts as a melt mixer for a designated melt stream of the polymer melt, and wherein in the area of the multi-channel system, means for at least indirectly influencing polymer melt are arranged.

2. Melt conductor according to claim 1, wherein a means for at least indirectly influencing the polymer melt is a static functional element, an actuator, a bimetal, a part arranged movably in a melt channel, a pump, a replaceable plug-in element and/or a cross-section modification means for the multi-channel system.

3. Melt conductor according to claim 1, wherein the melt conductor, in particular the melt conductor block, has an inspection opening with an external access to the multi-channel system.

4. Melt conductor according to claim 1, wherein the melt conductor, in particular the melt conductor block, has a valve seat with an external access to the multi-channel system.

5. Melt conductor according to claim 1, wherein one the melt conductor, in particular the melt conductor block, has a through opening with an external access to the multi-channel system, by means of which a medium can be conveyed towards and/or away from the multi-channel system.

6. Melt conductor according to claim 5, wherein the through opening is configured for adding an additive in at least one melt channel of the multi-channel system.

7. Melt conductor according to claim 2, wherein the replaceable plug-in element is adapted to locally alter a channel geometry of at least one of the melt channels and/or to fluidically interconnect at least two of the melt channels of the multi-channel system.

8. Melt conductor according to claim 1, wherein a means for at least indirectly influencing the polymer melt is a manipulating device which can be selectively and alternately activated and deactivated for manipulating melt areas arranged inside the melt conductor block for conveying polymer melt.

9. Melt conductor according to claim 8, wherein the manipulating device is temperature-controlled.

10. Melt conductor according to claim 1, wherein the bimetal is adapted to locally alter a channel geometry of at least one of the melt channels in dependence on a temperature change at the melt conductor block.

11. Melt conductor according to claim 1, wherein the melt conductor block has a medium channel, in particular for a circulating fluid supply, especially for temperature control, and/or for an electric line and/or a measuring unit.

12. Melt conductor according to claim 2, wherein the static functional element is a static mixing element.

13. Extruding die for an extrusion facility for manufacturing extrusion products, comprising a melt conductor according to claim 1, the melt conductor being adapted to distribute and/or mix at least one designated polymer melt.

14. Extruding die according to claim 13, characterized by an extrusion nozzle output having a width of more than 5,000 mm, preferably more than 6,000 mm or more than 8,000 mm.

15. Extrusion facility for manufacturing extrusion products, comprising an extruding die according to claim 13.

16. Method of operating an extrusion facility according to claim 15, the extrusion facility being fed with at least one extrudible polymer, in particular at least one plastic, which is plasticized to form a respective polymer melt, the respective polymer melt being fed to the melt conductor which distributes and/or mixes the respective polymer melt.

Description

[0133] In the drawings:

[0134] FIG. 1 is a schematic view of a possible structure of an extrusion facility having a melt conductor comprising a melt conductor block and a multi-channel system according to a first alternative;

[0135] FIG. 2 is a schematic perspective view of the multi-channel system according to FIG. 1, the melt conductor being embodied as a melt distributor;

[0136] FIG. 3 is a schematic perspective view of a second alternative embodiment of the multi-channel system, the melt conductor being embodied as a melt mixer;

[0137] FIG. 4 is a schematic perspective view of a third alternative embodiment of the multi-channel system, the melt conductor being partly embodied as a melt distributor and partly as a melt mixer;

[0138] FIG. 5 is a schematic perspective view of a fourth alternative embodiment of the multi-channel system, the melt conductor being partly embodied as a melt mixer and partly as a melt distributor;

[0139] FIG. 6A is a schematic perspective view of a fifth alternative embodiment of the multi-channel system, the melt conductor being embodied as a melt distributor;

[0140] FIG. 6B is another schematic perspective view of the fifth alternative embodiment according to FIG. 6A;

[0141] FIG. 6C is a further schematic perspective view of the fifth alternative embodiment according to FIGS. 6A and 6B;

[0142] FIG. 7A is a schematic top view of a sixth alternative embodiment of the multi-channel system, the melt conductor being embodied as a melt distributor;

[0143] FIG. 7B is a schematic perspective view of the sixth alternative embodiment according to FIG. 7A;

[0144] FIG. 7C is another schematic perspective view of the sixth alternative embodiment according to FIGS. 7A and 7B;

[0145] FIG. 7D is a further schematic perspective view of the sixth alternative embodiment according to FIGS. 7A through 7C;

[0146] FIG. 8 is a schematic perspective view of a seventh alternative embodiment of the multi-channel system, with the melt conductor being embodied as a melt distributor;

[0147] FIG. 9 is a schematic perspective view of an eighth alternative embodiment of the multi-channel system, with the melt conductor being embodied as a melt distributor;

[0148] FIG. 10A is a schematic perspective view of a ninth alternative embodiment of the multi-channel system, the melt conductor being embodied as a melt distributor;

[0149] FIG. 10B is a schematic top view of the ninth alternative embodiment in FIG. 10A;

[0150] FIG. 11 is a schematic partial sectional view of a tenth alternative embodiment of a multi-channel system;

[0151] FIG. 12A is a schematic partial sectional view of a melt channel of a multi-channel system in an eleventh alternative embodiment, a bimetal being shown in a non-deformed state;

[0152] FIG. 12B is a schematic partial sectional view of the melt channel in FIG. 12A, the bimetal being shown in a deformed state;

[0153] FIG. 13 is a schematic partial sectional view of a melt channel of a multi-channel system according to a twelfth alternative embodiment;

[0154] FIG. 14 is a schematic partial sectional view of a melt channel of a multi-channel system according to a thirteenth alternative embodiment;

[0155] FIG. 15 is a schematic partial sectional view of a the melt conductor block according to a fourteenth alternative embodiment; and

[0156] FIG. 16 is a schematic partial sectional view of the melt conductor block according to a fifteenth alternative embodiment.

[0157] FIG. 1 is a strongly simplified presentation of an extrusion facility 3. The extrusion facility 3 comprises a provision unit 23 adapted to provide and process a polymer melt 24, in the present case a plastic material. The provision unit 23 is presently the extruder (not presented in detail here) which plasticizes at least one extrudible polymer 29 to form the polymer melt 24. The provision unit 23 can also be adapted for providing one or more different polymer melts 24 with the same or with different properties. The polymer melt 24 is continuously fed by the provision unit 23 into an extruding die 2, comprising a melt conductor 1 and an extrusion nozzle 14 downstream in the designated direction of flow 25 of the polymer melt 24. The extruding die 2 is integrated in the continuously operating extrusion facility 3 in which the polymer melt 24 is continuously conveyed through the melt conductor 1 in a global machine direction 18, the expressions downstream and upstream referring to this global machine direction 18.

[0158] The melt conductor 1 which is adapted as a melt distributor in this first example of embodiment has a melt conductor block 4 with a multi-channel system 5 which extends three-dimensionally inside the melt conductor block 4. The melt conductor block 4 is manufactured by means of an additive manufacturing method like the multi-channel system 5 and can be integrated in the continuously operating extrusion facility 3 as a replaceable component of the melt conductor 1. The multi-channel system 5 according to the first embodiment in FIG. 1 is represented in detail in FIG. 2A. The melt conductor block 4 can be formed massively as a block or delicately with supporting structures. In this case, the multi-channel system 5 is supported by supporting structures arranged spatially around the multi-channel system 5, which are not shown here.

[0159] The provision unit 23 is flanged to an input side 26 of the melt conductor block 4, the extrusion nozzle 14 being formed at the output side 27 of the melt conductor block 4 such that also the extrusion nozzle 14 is manufactured with an additive manufacturing method, namely together with the melt conductor block 4. On the output side 27 of the melt conductor block 4, depending on requirements on the extrusion facility 3, the extrusion product 30 and the extrusion nozzle 14, a collection chambernot shown herecan be formed into which the multi-channel system 5 opens, the collection chamber being adapted to receive the polymer melt 24 distributed by the melt conductor 1 embodied as a melt distributor and to feed it continuously to the extrusion nozzle 14. The collection chamber can also be embodied such that a breaker plate and/or a filter sieve is integrated in it. As can be seen in FIGS. 2 through 10B, the multi-channel system 5 has one or more outputs 7 adapted to direct the polymer melt 24 for feeding the extrusion nozzle 14 into the collection chamber or directly into the extrusion nozzle. The extrusion nozzle 14 shown in FIG. 1 has an extrusion nozzle output 22 with a width B of more than 5,000 mm The width B defines the width of an extrusion product 30 manufactured by the extrusion facility, which in FIG. 1 is embodied as a film.

[0160] The melt distributor 1 distributes the polymer melt 24 according to FIG. 2 in the multi-channel system 5, with respect to its designated direction 25 of flow, from an input 6, arranged at an input side 26 of the melt conductor block 4, which in this case is embodied as a melt distributor block, via several branchings 8 arranged in series, several levels 9a, 9b of sub-branches 10 and several interposed levels of divided melt channels 11 to a plurality of outputs 7 fluidically connected to the input 6 and arranged on an output side 27 of the melt conductor block 4. Thus, the multi-channel system 5 has an input 6 and a plurality of outputs 7 fluidically connected to the input 6. The input 6 on the input side 26 of the melt conductor block 4 is consequently embodied as an input opening through which the polymer melt 24 is fed into the multi-channel system 5 of the melt conductor block 4.

[0161] For simplification purposes, the multi-channel system 5 in FIG. 2A is only shown with one branching 8 and two levels 9a, 9b of sub-branches 10. The other sub-branches 10 and melt channels are substantially formed in an analogous manner to distribute the polymer melt 24 over the respective width B of the extrusion nozzle output 22. Thus, three or more levels of sub-branches 10 are possible as well. In the designated direction 25 of flow of the polymer melt 24, a melt channel 11a of the a.sup.th level 12a is arranged between the input 6 and the branching 8, sub-branches 10 of a b.sup.th level 12b of melt channels 11b between the branching 8 and the first level 9a, and sub-branches 10 of a c.sup.th level 12c of melt channels 11c between the first level 9a of sub-branches 10 and the second level 9b of sub-branches 10. The second level 9b of sub-branches 10 is also followed by a d.sup.th level 12d of melt channels 11d. FIG. 2A also shows that the number of melt channels 11 increases with each level; that is, one melt channel 11a of the a.sup.th level divides into two melt channels 11b of the b.sup.th level; the two melt channels 11b of the b.sup.th level in turn each divide into two melt channels 11c of the c.sup.th level; i.e. in total four melt channels 11c are formed, etcetera. In other words, the number of melt channels 11 doubles from one level to the subsequent level in the direction 25 of flow. Therefore, also the multi-channel system 5 and its individual cavities in the form of melt channels 11, branching 8 and sub-branches 10 are manufactured by the additive manufacturing method. Furthermore, additional cavities can be provided e.g. in the form of a collection chamber, local expansions 28 or junctions which will be explained in more detail in the further description of alternative embodiments. Also, the cavities can be embodied as distribution or mixing chambers (not shown here) or the like.

[0162] In this embodiment, the melt channel 11a of the a.sup.th level 12a has a first local cross-section smaller than the second local cross-section of the divided melt channels 11b of the b.sup.th level 12b. Every local cross-section of the divided melt channels 11b of the b.sup.th level 12b is again larger than the local cross-section of the divided melt channels 11c of the c.sup.th level 12c etcetera.

[0163] When smaller or larger local cross-sections of the respective melt channel 11 are mentioned, this means that the melt channel 11 has a larger or smaller cross-section, respectively, over at least half the length of the respective melt channel 11, preferably at least ? the length of the respective melt channel 11, preferably at least ? the length of the respective melt channel 11.

[0164] Here, the melt channel 11a of the a.sup.th level 12a is oriented towards the input 6 in the designated direction 25 of flow of the polymer melt 24 and the melt channels 11b of the b.sup.th level 12b are oriented towards the output 7 with respect to the melt channel 11a of the a.sup.th level 12a. The melt channels 11c of the c.sup.th level 12c are oriented towards the input 6 with respect to the melt channels 11d of the d.sup.th level 12d, the melt channels 11d of the d.sup.th level 12d being oriented towards the output 7 with respect to the melt channels 11 of the a.sup.th, b.sup.th and c.sup.th levels 12a, 12b, 12c. Accordingly, the melt conductor 1 acts as a melt distributor.

[0165] In FIG. 3, a second alternative multi-channel system 5 of a second alternative melt conductor block 4, which is not shown here, the melt conductor 1 is, in contrast to FIG. 2, arranged in reverse order in the extruding die 2 and the extrusion facility 3 and is consequently embodied as a melt mixer in this alternative example of embodiment. This is due to the fact that the melt conductor 1 has a plurality of inputs 6, eight in this case, on the input side 26 of the melt conductor bock 4 via which one or up to eight identical or at least partly different polymer melts 24 are combined into an output 7 fluidically connected to the inputs 6 and arranged on the output side 27 of the melt conductor block 4. In the present case, the melt conductor block 4 is not shown but only, for better clarity, the multi-channel system 5. The multi-channel system 5 is formed substantially identical with the embodiment in FIG. 2. The only difference is that the polymer melt 24 is not distributed through the multi-channel system 5 but that up to eight different polymer melts 24 can be combined by means of the multi-channel system 5. The multi-channel system 5 presently also has several branchings 8 arranged in series, several levels 9a, 9b of sub-branches 10 and several levels 12a, 12b, 12c, 12d of divided melt channels 11a, 11b, 11c, l1d arranged between them; however seen against the designated direction 25 of flow of the polymer melt 24, namely from the output side 27 to the input side 26.

[0166] In opposition to the designated direction 25 of flow of the polymer melt 24, a melt channel 11a of the a.sup.th level 12a is arranged between the respective output 7 and the branching 8; between the branching 8 and the first level 9a of sub-branches 10, a b.sup.th level 12b of melt channels 11b, and between the first level 9a of sub-branches 10 and the second level 9b of sub-branches 10, a c.sup.th level 12c of melt channels 11c. A d.sup.th level 12d of melt channels 11d is also arranged downstream of the second level 9b of sub-branches 10, which channels are fluidically directly connected to the inputs 6. Thus, in the designated direction 25 of flow of the polymer melt 24, the number of melt channels 11 decreases with each level from the inputs 6 to the output 7; that is, every two of the presently eight melt channels 11d of the d.sup.th level 12d are combined to one melt channel 11c of the c.sup.th level 12c, i.e. in total four melt channels 11c of the c.sup.th level 12c. Every two of the four melt channels 11c of the c.sup.th level 12c are again combined to one melt channel 11b of the b.sup.th level 12b, i.e. in total there are two melt channels 11b of the b.sup.th level 12b, and from the two melt channels 11b of the b.sup.th level 12b, a melt channel 11a of the a.sup.th level is formed which is directly fluidically connected to the output 7.

[0167] In reverse order to the embodiment in FIG. 2, the local cross-section of the respective melt channel level increases in the designated direction 25 of flow of the polymer melt 24 with each lower level. The melt channels 11a of the a.sup.th level 12a are oriented towards the output 7 in the designated direction 25 of flow of the polymer melt 24 and the melt channels 11b of the b.sup.th level 12b are oriented towards the inputs 6 with respect to the melt channels 11a of the a.sup.th level 12a. The melt channels 11c of the c.sup.th level 12c are oriented towards the output 7 with respect to the melt channels 11d of the d.sup.th level 12d, the melt channels 11d of the d.sup.th level 12d being oriented towards the inputs 6 with respect to the melt channels 11a, 11b, 11c of the a.sup.th, b.sup.th and c.sup.th levels 12a, 12b, 12c. Accordingly, the melt conductor 1 acts as a melt mixer.

[0168] FIG. 4 shows a third alternative multi-channel system of a third alternative melt conductor block 4 not shown here. The present multi-channel system 5 is formed as a combination of a melt conductor 1 which is partly formed as a melt distributor and partly as a melt mixer. On the input side of the melt conductor block 4, first an input 6 into the multi-channel system 5 is provided, the melt channel 11a of the a.sup.th level 12a being separated into a plurality of melt channels 11d of the d.sup.th level 12d in analogy to the embodiment in FIG. 2A. Further downstream in the designated direction 25 of flow of the polymer melt, starting from the melt channels 11d of the d.sup.th level 12d, the melt channels 11 are again combined in a manner analogous to the embodiment in FIG. 3 via melt channels 11c, 11b of the c.sup.th level 12c and of the b.sup.th level 12b down to a melt channel 11a of the a.sup.th level 12a or down to the output 7, respectively.

[0169] In FIG. 5, a fourth alternative multi-channel system 5 of a fourth alternative melt conductor block 4not shownis represented, a combination of a melt conductor 1 formed partly as a melt mixer and partly as a melt distributor being shown here as well. The method of functioning, however, is opposite to the one shown in the embodiment of FIG. 4. On its input side 26, the melt conductor block 4 has several inputs 6 to the multi-channel system 5, the melt channels 11d of the d.sup.th level 12d, which are fluidically directly connected to the inputs 6, being combined along the designated direction 25 of flow of the polymer melt 24, in a manner analogous to the example of embodiment in FIG. 3, from one level to the other up to a melt channel 11a of the a.sup.th level 12a. Further downstream, this melt channel 11a of the a.sup.th level 12a is divided, in a manner analogous to the embodiment in FIG. 2, from one level to the other via a branching 8, several levels 9a, 9b of sub-branches 10 as well as interposed levels 12b, 12c, 12d of melt channels 11b, 11c, 11d until a plurality of outputs 7 are arranged on the output side 27 of the melt conductor block 4.

[0170] The multi-channel system 5 according to the embodiment in FIG. 4 and according to the embodiment in FIG. 5 is not limited to the shape and arrangement described herein. It is also possible to provide upstream and/or downstream of the respective multi-channel system 5 additional portions formed as melt distributors and/or melt mixers which can be embodied and combined as desired. It is of an advantage, however, if the polymer melt 24 always has the same melt history at the output(s) 7, independently of which melt channels 11 or melt channel sequence it flows through. In case of eight melt channels 11d of the d.sup.th level 12d, the polymer melt 24 is therefore divided into a maximum of eight different melt streams. A same history of the polymer melt 24 in this connection means that all melt streams of the polymer melt 24 have traversed the same path through the multi-channel system 5 when they arrive at the output(s) 7 and have flown through the same number of melt channels 11, branchings 8 and sub-branches 10.

[0171] The embodiments according to FIGS. 6A through 10B, which are described in the following, exclusively refer to melt conductors 1 formed as melt distributors, with the polymer melt 24 in the multi-channel system 5 being distributed from a respective input 6 to a plurality of outputs 7. Thus, the arrangement and numbering of the levels of melt channels 11 as well as of the branchings 8 and levels of sub-branches 10 are analogous to the first embodiment shown in FIG. 2. Naturally, the following embodiments are also suitable for implementing the melt conductor 1 as a melt mixer or as any combination of melt mixer and melt distributor.

[0172] In the embodiments according to FIGS. 1 through 5, the multi-channel system 5 is in each case substantially formed lying on one plane, the respective input 6 and output 7 as well as all melt channels 11, branchings 8 and sub-branches 10 being consequently arranged on one common plane. Therefore, at least three degrees of freedom are used for forming the multi-channel system 5.

[0173] In contrast, a fifth alternative multi-channel system 5 of a fifth alternative melt conductor block 4not shown hereis represented in FIGS. 6A through 6C, the channel system 5 branching out three-dimensionally in space using five degrees of freedom. As shown in FIG. 6C, the melt channels 11 extend in the direction of flow of the polymer melt 24, starting from the input 6 and distributed over several levels 12a-12e, at least partly downwards, to the left, to the right, into and out of the leaf level. The melt channels 11a-11e fluidically connected to the input 6 thus branch out over the branchings 8 and sub-branches 10 down to the outputs 7 which in the present arrangement are distributed over two substantially parallel planes. The first level 9a of sub-branches 10 is formed such that the melt channels 11c of the c.sup.th level 12b substantially extend rotated by 90? with respect to the melt channels 11b of the b.sup.th level 12b, such that starting from each melt channel 11c of the c.sup.th level, a separate distribution system 29a, 29b, 29c, 29d is formed, such that the first and the second distribution system 29a, 29b are arranged on one plane and the third and the fourth distribution system 29c, 29d are arranged on a second plane.

[0174] By means of such a melt conductor 1, it is possible in an easy manner to distribute the polymer melt 24 not only evenly in width in a manner analogous to FIG. 2 but also homogeneously in a direction transverse thereto, that is, in height or in depth, depending on the direction of view, so that the polymer melt 24 can exit from the melt conductor block 4 on a comparably large surface. This is especially suitable for manufacturing filaments or endless filaments and in particular for producing spunbonded fabrics by means of multirow nozzle dies.

[0175] Independently of the arrangement of the branching 8 and the sub-branches 10 in relation to the melt channels 11 and their arrangement in three-dimensional space, the local cross-section of the melt channels 11 decreases from one level to the next 12a-12e down to the outputs 7, the melt channels 11 of each level 12a-12e being always formed symmetrical in all distribution systems 29a-29d and the separated melt streams of the designated polymer melt 24 having the same melt history.

[0176] The outputs 7 of the first and second distribution systems 29a, 29b or of the first plane, respectively, are thus located on a theoretical straight first line and the outputs 7 of the third and the fourth distribution system 29c, 29d or of the second plane on a theoretical straight second line. Both lines and both planes are arranged in parallel to one another. Since all melt channels 11 are connected to a single input 6, all melt streams have the same material properties at the respective output 7 due to conveying the same polymer melt 24.

[0177] The melt conductor block 4 further has several inspection openings 13a-13d for the multi-channel system 5. The inspection openings 13a-13d are arranged in a curved portion 46 between a channel portion 47 which is here substantially horizontal and a substantially vertical channel portion 48 of the melt channel 11c of the c.sup.th plane and extend from there each at an incline upwards in the direction of a lateral surface 49 of the melt conductor block 4. The inspection openings 13a-13d can be used for inspection or flushing of the multi-channel system 5 and can accordingly have basically any configuration on the multi-channel system 5. In the present example of embodiment, the first and the second inspection opening 13a, 13b are formed such that they each exit from the melt conductor block 4 via a respective curved portion 50 perpendicularly to a substantially vertical lateral surface 49 of the melt conductor block 4. By way of example, the third and the fourth inspection opening 13c, 13d are configured such that they each exit from the melt conductor block 4 via a respective curved portion 50 perpendicularly to a horizontal lateral surface 49 of the melt conductor block 4.

[0178] In addition, the melt conductor block 4 has a medium channel 20 extending spatially between the melt channels 11 of the multi-channel system 5, here between the two levels of the distribution systems 29a-29d, and implements a fluid guidance. The fluid guidance is used for temperature control of the melt conductor block 4 and therefore of the polymer melt 24 guided in the multi-channel system 5. The medium channel 20 is not fluidically connected to the melt channels 11 of the multi-channel system 5 and implements temperature control of the melt conductor 1 and in particular of the melt conductor block 4 during operation of the extrusion facility 3. Furthermore, any number of additional medium channels of any structure can be provided which are arranged fluidically separated from the melt channels 11 of the multi-channel system 5 in the melt distributor block 4. The additional medium channels can also be embodied as drying shafts which are adapted, for instance, for accommodating an electric line and/or a measuring unit.

[0179] In FIGS. 7A through 7D, a sixth alternative multi-channel system 5 of a sixth alternative melt conductor block 4not shown hereis represented, the multi-channel system here branching out three-dimensionally in space using six degrees of freedom. In this embodiment, it is shown that the two melt channels 11b of the b.sup.th level partly extend in opposition to a global machine direction 18. The global machine direction 18 leads from the input 6 to the output 7 of a designated melt flow of the polymer melt 24. Each melt channel 11b of the b.sup.th level 12b has a local machine direction 19 which can always be the same in the longitudinal direction of the melt channel 11 or which may change in the longitudinal direction of the melt channel 11, depending on the configuration and extension of the respective melt channel 11. It may be of an advantage if the local machine direction extends at least partially against the global machine direction 18. This can especially be seen in FIG. 7A.

[0180] A global machine direction 18 is the arrangement of the melt conductor 1, in particular the melt conductor block 4, in the extrusion facility 3, the global machine direction 18 extending along the designated direction of flow between the provision unit and the extrusion nozzle 14 on the melt conductor block 4. That is, the global machine direction 18 is a spatial extension of the melt conductor 1, in particular the melt conductor block 4, in the extrusion facility 3 taking into account the input side 26 and the output side 27 of the multi-channel system 5 for the designated polymer melt 24.

[0181] A local machine direction 19 may deviate locally from the global machine direction 18, the local machine direction 19 referring to the local orientation of the multi-channel system 5, in particular of the respective melt channel 11 in relation to the global machine direction 18. The local machine direction 19 extends coaxially with the longitudinal axis of the melt channel 11 in the designated direction 25 of flow of the polymer melt 24. In a particularly simplified case, the local machine direction 19 can in portions preferably coincide with the global machine direction 18 if the multi-channel system 5 has an input 6 on an input side of the melt conductor block 4 and an output 7, which is fluidically connected and coaxially arranged therewith, on an output side of the melt conductor block 4 opposite to the input side. The orientation of the melt channel 11 in space and thus the local machine direction 19 can, in this case, be at least partially coaxial with the global machine direction 18.

[0182] Since the multi-channel system 5 is formed so as to extend three-dimensionally inside the melt conductor 1 or the melt conductor block 4, respectively, the local machine direction 19 regularly deviates from the global machine direction 18. Because all six degrees of freedom can be exploited to form the multi-channel system 5, an inclined arrangement of the respective melt channel 4 with respect to the global machine direction 18 is possible. It is also conceivable, however, and can be advantageous, especially for saving installation space, to provide for the local machine direction 19 to extend, with respect to the global machine direction 18, in portions in the opposite direction.

[0183] Thus, in a particular example of embodiment, melt channels 11 of the multi-channel system 5 can be guided back nearly to the input side of the melt conductor 1, in particular the melt conductor block 4. The advantage of guiding the local machine direction 19 of the melt channels 11 opposite to the global machine direction 18 therefore consists in the fact that since any desired arrangement of the melt channels 11 in relation to the global machine direction 18 is possible, the melt conductor 1 or melt conductor block 4 can be embodied such as to save a large amount of installation space. In addition, the melt channels 11 can be arranged to bypass connecting or fastening elementsnot shown hereas desired, in particular screws, threads or the like.

[0184] In the present case, the input 6 and the outputs 7 of the multi-channel system 5 are substantially arranged on a first plane, the melt channels 11b of the b.sup.th level 12b extending partly transversely to this first plane such that the first level 9a of sub-branches 10 is arranged on a second plane parallel to the first plane. The attached melt channels 11c of the c.sup.th level 12c extend partly on the second plane and are guided back to the first plane for further distribution of the polymer melt 24. By guiding the melt channels 11 three-dimensionally in space, and in particular by guiding the local machine direction 19 of the melt channels 11 partly against the global machine direction 18, the polymer melt 24 is broadly distributed over a smaller axial construction space, that is, in the global machine direction 18 of the melt conductor 1. In this manner, the melt conductor 1 can be constructed to be more compact.

[0185] By means of such a melt conductor block 4, it is possible to distribute the polymer melt 24 such that in particular non-woven fabrics with 20 to 10,000 individual filaments per meter width can be produced.

[0186] FIG. 8 shows a seventh example of embodiment with a seventh alternative multi-channel system 5. The multi-channel system 5 is substantially identical with the multi-channel system 5 in FIG. 2. The main difference is that the melt distributor block 4, here in the area of the melt channels 11c of the c.sup.th level 12c, each has a static functional element 21 in the form of a static mixing element for influencing the designated polymer melt 24. The respective functional element 21 is arranged within a local broadening 28 of the melt channels 11c of the c.sup.th level 12c and has the form of intersecting struts. The respective functional element 21 is arranged in one of the melt channels 11c of the c.sup.th level 12c between a sub-branch 10 of the first level 9a and a sub-branch 10 of the second level 9b. Before and after the local broadening 28, the cross-sectional dimension and shape of the respective melt channel 11c of the c.sup.th level 12c are substantially equal. The respective static functional element 21 achieves a mixing of the polymer melt 24 conducted and distributed inside the melt channels 11c of the c.sup.th level 12c. In this manner homogenization of the melt strand conducted inside the respective melt channel 11 of the polymer melt 24, in particular of its flow and material properties, can be ensured. Alternatively, the static mixing element can also be arranged directly within the respective melt channel and not in a local broadening.

[0187] As an alternative, an eighth embodiment according to FIG. 9 shows an eighth alternative multi-channel system 5 which has, instead of the broadening 29 with the functional element 21 arranged therein, a pump 36 as a means for at least indirectly influencing the polymer melt 24 at the respective melt channel 11c of the c.sup.th level 12c in order to convey the polymer melt through the multi-channel system 5. The provision of pumps 36 is an advantage in multi-channel systems with a plurality of melt channel levels and branching levels, the polymer melt being distributed over a large width of the melt conductor block 4 or joined from a large width of the melt conductor block 4, respectively. The embodiment in FIG. 9 can easily be combined with the embodiment in FIG. 8.

[0188] FIGS. 10A and 10B show a ninth alternative example of embodiment of a ninth alternative multi-channel system 5. The multi-channel system 5 is formed in a manner substantially analogous to the multi-channel system 5 in FIG. 2. We therefore refer to the corresponding description, where for reasons of simplicity, a repetition of identical reference numbers is omitted unless it is absolutely necessary.

[0189] In addition to the multi-channel system 5, the melt conductor block 4 also has a through opening 17 formed as a channel system which is fluidically connected with the multi-channel system 5 in the area of the outputs 7 of the multi-channel system 5 via junctions 15 so as to conduct a medium towards and/or away from the multi-channel system 5, depending on requirements.

[0190] Here, the through opening 17 is embodied for adding an additive into the melt channel 11d of the d.sup.th level 12d of the multi-channel system 5. In other words, an additivenot shown in detail hereis added into a first input 38 of the through opening 17, the additive being distributed via the channels 39 such that one channel 39 of the through opening 17 is connected with one corresponding melt channel 11d of the d.sup.th level 12d of the multi-channel system 5 via a respective junction 15. Thus, the additive is mixed with the polymer melt 24 by means of the junctions 15 so as to achieve certain material properties of the polymer melt 24.

[0191] Thus, the through opening 17 formed as a channel system has, in a manner analogous to the multi-channel system 5, channels 39 which are separated via branchings 8 and several levels 9a of sub-branches 10 such that additives can be added to the melt streams of the polymer melt 24 flowing in the melt channels 11d of the d.sup.th level 12d of the multi-channel system 5. Here, the polymer melt 24 in the multi-channel system 5 and the additive in the through opening 17 are only combined directly before exiting the multi-channel system or the melt conductor block 4. In this manner, a compound is produced which is atomized via the outputs 7 or directed to an extrusion nozzle (not shown here).

[0192] In addition, the channels 39 of the through opening 17 can be arranged in parallel, perpendicular or at an incline to the melt channels 11 of the multi-channel system 5. Here, the channels 39 of the through opening 17 conducting the additive are arranged at an incline such that from one level to the next, the channels 39 continuously approach the melt channels 11a-11d of the multi-channel system 5 until the channels 39 and the melt channels 11d of the d.sup.th level 12d meet in the area of the respective junction 15 and achieve mixing of the designated polymer melt 24 with the additive.

[0193] Alternatively, a venting, e.g a discharge of gases from the multi-channel system 5 can also be performed via the channel system of the through opening 17. The junctions 15 can also be arranged in different places of the multi-channel system 5, especially in the area of other levels of melt channels 11, branchings 8 or sub-branches 10.

[0194] In FIGS. 11 through 16, different embodiments of means for at least indirectly influencing the polymer melt 24 are shown. They can be arranged in individual melt channels 11, in several melt channels 11 of one level or in all melt channels 11 of the multi-channel system 5 and can be combined as desired, depending on requirements on the polymer melt and/or on the extrusion product 30.

[0195] FIG. 11 shows a partial sectional view of a melt channel 11 of the multi-channel system 5not shown here in detailaccording to a tenth alternative embodiment. Here, the means for at least indirectly influencing the polymer melt 24 comprise an actuator 33 driving a wheel 40 arranged inside the melt channel 11 and rotatable about a rotational axis R. The rotational axis R of the wheel 40 here extends transversely to the designated direction 25 of flow of the polymer melt 24. The rotation of the wheel 40 is controlled by means of a control unit 44 arranged outside the melt conductor block 4, which can comprise an adaptation of a rotational direction and/or rotational speed and/or an activation or deactivation of a rotation of the wheel 40. By means of the wheel 40, the polymer melt 24 (not shown here) flowing in the direction 25 of flow is mixed and homogenized. The actuator 33 can be activated or deactivated depending on the material properties, in particular the flow properties, of the polymer melt 24. The actuator 33 comprises a drive unit (not shown here) for driving the wheel 40 which is also arranged inside the melt conductor block and in the area of the melt channel 11.

[0196] The rotational axis R of the wheel 40 can alternatively be arranged in parallel to the designated direction 25 of flow of the polymer melt 24 so that the wheel 40 mixes the polymer melt in the form of a propeller, rotor or turbine wheel. It is also possible to arrange the wheel 40 in the melt channel 11 so that it is not driven.

[0197] In FIGS. 12A and 12B, the means for at least indirectly influencing the polymer melt 24 is embodied in an eleventh alternative embodiment as a bimetal 34. The bimetal 34 is here arranged circumferentially around the melt channel 11 and consists of a first layer 41a and a second layer 41b arranged radially outside the same, the second layer 41b resting with its entire surface on the first layer 41a. The bimetal 34 is here produced by means of an additive manufacturing method as well, namely during formation of the melt channel 11.

[0198] The layers 41a, 41b of the bimetal consist of two different metals with different thermal expansion coefficients, the metals being mutually material and/or form-fitting connected. Due to the different thermal expansion coefficients of the metals, one of the layers 41a, 41b, presently the first layer 41a, expands due to heating of the melt conductor block 4 and/or the polymer melt 24 more than the other, causing the bimetal to locally deform. At a first temperature of the bimetal 34, shown here in FIG. 12A, the melt channel 11 has a first diameter D1 which is larger than a second diameter D2 of the melt channel 11 shown in FIG. 12B which adjusts to a second temperature when the bimetal 34 is heated. Therefore, a temperature-dependent local tapering of the local cross-section of the melt channel 11 takes place due to a heating of the bimetal 34. Alternatively, the bimetal 34 or the metal layers 41a, 41b of the bimetal 34 can be embodied such that widening of the local cross-section of the melt channel 11 takes place due to heating so that D2 is larger than D1.

[0199] FIG. 13 shows a partial longitudinal section through a melt channel 11 according to a twelfth example of embodiment, with a part 35 arranged movably within the melt channel 11 as a means for influencing the polymer melt 24. The movably arranged part 35 is a wheel 40 arranged rotatably with respect to the melt conductor block 4 or the wall of the melt channel 11 which rotates, due to kinetic energy of the polymer melt 24 flowing in the designated direction 25 of flow, about a rotational axis R and allows mixing of the polymer melt 24 in a manner substantially analogous to FIG. 11.

[0200] In FIG. 14, a partial sectional view of a melt channel 11 of the multi-channel system 5 according to a thirteenth alternative embodiment, the means for at least indirectly influencing the polymer melt 24 comprise a manipulating device 32, which can be selectively and alternately activated and deactivated, for manipulating melt areas arranged in the melt conductor block 4 for directing polymer melt 24. In other words, the designated polymer melt 24 conducted inside the melt channels 11 is influenced by switching the manipulating device 32 on and off. Here, the manipulating device 32 is temperature-controlled. This means that a control or an alteration of the properties of the polymer melt 24 is performed by means of the manipulating device 32 in dependence on the temperature of the material of the melt conductor block 4 and/or on the temperature of the polymer melt 24.

[0201] In the present example of embodiment, the manipulating device 32 is embodied as a heating strip arranged at least partly circumferential and radially spaced from the melt channel 11. The heating strip is sleeve-shaped, an activation or deactivation of the heating strip taking place in dependence on the temperature of the designated polymer melt 24. Activation of the manipulating device 32 may for instance be necessary to reduce the viscosity of the designated polymer melt 24. In contrast, deactivation of the manipulating device 32 may be necessary if the melt conductor block 4 has a desired material temperature, which guarantees certain flow properties of the designated polymer melt 24, making an additional reduction of viscosity unnecessary.

[0202] Alternatively or in addition, it is possible to effectively arrange heating elements and/or heating strips of the manipulating device 32 on outer surfaces of the melt conductor block 4 as means to at least indirect influencing so as to achieve temperature control in some or all parts of the melt conductor block 4 and thus in the polymer melt 24 conveyed in the melt channels 11 inside the melt conductor block 4.

[0203] FIG. 15 shows a partial longitudinal section through a melt conductor block 4 according to a fourteenth example of embodiment. Here, the multi-channel system is partially shown, a replaceable plug-in element 31 being accommodated in a recess 42shown in dashed linesof the melt conductor block 4 and being adapted to locally alter a channel geometry of at least one of the melt channels 11 and/or to fluidically interconnect at least two of the melt channels 11 of the multi-channel system 5. In the present embodiment, the plug-in element 31 has a branching 8 which divides a first melt channel 11a into two second melt channels 11b of a level downstream in the direction 25 of flow of the designated polymer melt 24. Here, the plug-in element 31 is embodied such that a local cross-section of the melt channels 11a, 11b remains constant. It is also conceivable, however, that the shape and/or type of cross-section of the melt channels 11a, 11b within the plug-in element 31 may change. It is also possible to arrange inside the plug-in element 31 means for at least indirectly influencing the polymer melt 24 as are described in FIGS. 11 through 14 or FIG. 16. This allows reacting to the requirements on the polymer melt 24 and/or the extrusion product 30 by simply replacing the plug-in element 31, for instance if polymer melts 24 or the desired type of product are changed. In particular, the flow properties of the polymer melt 24 and/or melt conveyance of the multi-channel system 5 may be adapted.

[0204] In FIG. 16, the means for at least indirectly influencing the polymer melt 24 according to an eleventh alternative embodiment is embodied as a cross-section modification means 37, in the present case as a valve. The cross-section modification means 37not shown in detail hereis arranged replaceably in the melt conductor block 4, which is only partially shown here, and is inserted via an external access 45 into a valve seat 16 formed in the melt channel 11. The cross-section modification means 37 is formed such that the melt channel 11 is sealed with respect to the external access 45. In addition, the cross-section modification means 37 embodied as a valve is configured to adapt a flow rate of the melt channel 11, where the flow rate can be changed during operation of the extrusion facility 3. Due to replaceable arrangement of the cross-section modification means 37 on the melt conductor block 4, the external access 45 can also be configured as an inspection opening or as a through opening for feeding or discharging a medium to or from the multi-channel system 5.

[0205] Depending on the configuration of the means for at least indirectly influencing the polymer melt, for instance in the form of a flap (not shown here) or a wall displaceable as desired by means of an actuator, individual melt channels and therefore individual or several segments of the multi-channel system can be temporarily closed, making it possible to produce by means of the extruding die extrusion products with different widths or to continuously alter the widths.

[0206] At this point, it is explicitly pointed out that features of the solutions described above, in the Claims or in the Figures can also be combined, if desired, so as to cumulatively achieve the features, effects and advantages. It is also explicitly mentioned that the embodiments in FIGS. 1 through 10B can also be implemented with two or more multi-channel systems.

[0207] It is understood that the embodiments explained above are only first embodiments of the invention, in particular of the melt conductor 1, the extruding die 2 and the extrusion facility 3 according to the invention. Thus, the implementation of the invention is not limited to these embodiments.

[0208] All features disclosed in the application documents are claimed as essential to the invention provided that they are novel individually or in combination with respect to the state of the art.

[0209] The embodiments shown here are only examples of the present invention and are therefore not to be understood as limiting. Alternative embodiments considered by the person skilled in the art are equally comprised by the scope of protection of the present invention.

LIST OF REFERENCE NUMBERS

[0210] 1 melt conductor [0211] 2 extruding die [0212] 3 extrusion facility [0213] 4 melt conductor block [0214] 5 multi-channel system [0215] 6 input of multi-channel system [0216] 7 output of multi-channel system [0217] 8 branching [0218] 9a first level of a branching [0219] 9b second level of a branching [0220] 9c third level of a branching [0221] 10 sub-branch [0222] 11 melt channel [0223] 11a divided melt channel of a first level [0224] 11b divided melt channel of a second level [0225] 11c divided melt channel of a third level [0226] 11d divided melt channel of a fourth level [0227] 11e divided melt channel of a fifth level [0228] 12a a.sup.th level of a melt channel [0229] 12a a.sup.th level of a melt channel [0230] 12b b.sup.th level of a melt channel [0231] 12b b.sup.th level of a melt channel [0232] 12c c.sup.th level of a melt channel [0233] 12c c.sup.th level of a melt channel [0234] 12d d.sup.th level of a melt channel [0235] 12d d.sup.th level of a melt channel [0236] 12e e.sup.th level of a melt channel [0237] 13a first inspection opening [0238] 13b second inspection opening [0239] 13c third inspection opening [0240] 13d fourth inspection opening [0241] 14 extrusion nozzle [0242] 15 junction [0243] 16 valve seat [0244] 17 through opening [0245] 18 global machine direction [0246] 19 local machine direction [0247] 20 medium channel [0248] 21 static functional element [0249] 22 extrusion nozzle output [0250] 23 provision unit [0251] 24 polymer melt [0252] 25 flow direction of polymer melt [0253] 26 input side of melt conductor block [0254] 27 output side of melt conductor block [0255] 28 local expansion of melt channel [0256] 29 polymer [0257] 30 extrusion product [0258] 31 plug-in element [0259] 32 manipulating device [0260] 33 actuator [0261] 34 bimetal [0262] 35 movably arranged part [0263] 36 pump [0264] 37 cross-section modification means [0265] 38 input of through opening [0266] 39 channel of through opening [0267] 40 wheel [0268] 41a first layer of bimetal [0269] 41b second layer of bimetal [0270] 42 recess in melt conductor block [0271] 43 valve [0272] 44 control unit [0273] 45 external access [0274] 46 curve portion of melt channel [0275] 47 horizontal channel portion of melt channel [0276] 48 vertical channel portion of melt channel [0277] 49 outer surface of melt conductor block [0278] 50 curve portion of inspection opening [0279] B width of extrusion nozzle output [0280] D1 first diameter of melt channel [0281] D2 second diameter of melt channel [0282] R rotational axis