Molten conductor for an extrusion die of an extrusion facility, extrusion die, extrusion facility, and method of operating such an extrusion facility
The fused conductor block with a multi-channel system addresses the challenge of uniform polymer melt distribution and mixing in extrusion dies, ensuring consistent shear stress and quality in extruded products.
Patent Information
- Application Number
- JP2022521566
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Priority Date
- 2020-07-10
- Filing Date
- 2020-10-14
- Publication Date
- 2025-09-10
- Estimated Expiration
- 2040-10-14
AI Technical Summary
Existing extrusion dies face challenges in uniformly distributing or combining polymer melt across varying cross-sectional areas due to shear stresses and structural limitations, particularly when producing products with small cross-sectional areas.
A fused conductor block with a multi-channel system is used, featuring a three-dimensional arrangement of melt channels that adjust cross-sectional areas and orientations to maintain uniform shear stress and distribution or mixing of polymer melt, manufactured partially by additive manufacturing.
This design ensures uniform distribution or mixing of polymer melt with consistent shear stress, reducing the risk of flow interruption and enabling the production of high-quality extruded products with minimal seams.
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Abstract
Description
[Technical Field]
[0001] The present invention relates to a fused conductor for an extrusion die of an extrusion installation having a fused conductor block with a multi-channel system.
[0002] The present invention also relates to an extrusion die for at least indirectly extruding or producing extruded products such as films, nonwovens, profiles, pipes, blown-molded parts, filaments, plates, semi-finished products, hoses, cables, composites, or semi-finished foam products. The extrusion die generally comprises one or more melt conductors embodied as melt distributors and / or melt mixers. Depending on the embodiment of the one or more melt conductors, the extrusion die is designed to distribute and / or mix the polymer melt supplied and delivered by at least one supply unit and to directly direct the polymer melt to the periphery of the extrusion die. In such cases, one or more outputs of each melt conductor function as an extrusion nozzle or nozzle output. Alternatively, a separate extrusion nozzle can be arranged downstream of one or more melt conductors, which deliver the polymer melt via the one or more melt conductors and at least indirectly direct the polymer melt from the extrusion die to the periphery. In this case, the extrusion die comprises a melt conductor and an extrusion nozzle downstream of the designated polymer melt.
[0003] The molten conductor and the extrusion nozzle may be separate components. However, it is also conceivable to make the molten conductor and the extrusion nozzle integrally. That is, the extrusion die may be an assembly of the above-mentioned components and other components depending on the design and requirements of the extrusion equipment. Thus, the nozzle output of the molten conductor or the extrusion nozzle, respectively, is the component that forms the extrusion product in the direction of the polymer melt flow.
[0004] A melt mixer is a component or assembly that receives a polymer melt to be plasticized at one or more inputs, which subsequently combine and mix through intersecting or connected melt channels until the polymer melt exits the melt mixer at one or more outputs, the number of which is less than the number of inputs. That is, the polymer melt is first split into multiple molten filaments, which are conducted in multiple melt channels and combined by and through a multi-channel system. In other words, the melt mixer has melt channels in a direction opposite to the designated flow direction of the polymer melt, and the channels are divided into at least one main branch and several levels of secondary branches. Conversely, the melt channels, and therefore the molten filaments, are also connected in the designated flow direction of the polymer melt by several levels of connecting ducts, resulting in fewer outputs at the output side of the melt mixer than at the inputs at the input side of the melt mixer.
[0005] In contrast, a melt distributor is a component or assembly that receives a plasticized polymer melt at one or more inputs, which subsequently splits into different melt channels until the melt is output at one or more outputs, the number of which is greater than the number of inputs in the melt distributor. Thus, the polymer melt is split into multiple molten filaments that are conducted through a multi-channel system. In other words, a melt distributor has a melt channel in a designated direction of polymer melt flow, which is split into melt sub-channels via at least one main branch and several levels of sub-branching. Conversely, the melt channels are connected through several levels of connecting ducts in a direction opposite to the designated direction of polymer melt flow, so that there are more output ports at the output side of the melt mixer than there are input ports at the input side of the melt mixer.
[0006] The invention also relates to an extrusion installation, in particular embodied as a cast film, meltblown, spunbond, blown film, monofilament or multifilament line, comprising an extrusion die with at least one melt conductor of the type described above, which is essentially designed to receive an extrudable polymer, convert it into or process it as a polymer melt, and then produce an extruded product by appropriately directing and subsequently atomizing the polymer melt.
[0007] The term "extrudable polymer" refers to those materials, mixtures, and commercially available additives that are essentially extrudable, i.e., can be processed by an extruder. In particular, it refers to thermoplastics such as polyvinyl chloride (PVC), polyethylene (PE), polypropylene (PP), polyamide (PA), acrylonitrile butadiene styrene copolymer (ABS), polycarbonate (PC), styrene butadiene (SB), polymethyl methacrylate (PMMA), polyurethane (PUR), polyethylene terephthalate (PET), polyvinyl alcohol (PVOH, PVAL), or polysulfone (PSU). In particular, the polymer can be a plastic polymer. Furthermore, biomaterials such as thermoplastic starch, solutions, and other materials are extrudable and can be used in the present solution instead of or in combination with plastic polymers. For simplicity, the terms "polymer" or "plastic polymer" are generally used in the context of this patent application.
[0008] The extrudable polymer can be supplied to the extrusion equipment in a substantially solid form, such as granules, powder, or flakes. Alternatively, at least a portion of the extrudable polymer may be available in a substantially liquid form. The supply unit for the extrudable polymer may be, for example, a reservoir that supplies the polymer in a form suitable for feeding the molten conductor. Alternatively, the supply unit may be, for example, an extruder that converts the extrudable polymer from a substantially solid form to a substantially liquid form, optimal for feeding the molten conductor. When feeding the molten conductor, the polymer melt is typically substantially completely melted or plasticized, or in solution, and then split and / or combined through the molten conductor. It is also possible for a portion of the polymer to be present in a substantially solid form or to be added to the substantially liquid polymer melt as an additive prior to feeding the molten conductor, with the solid component having a different melting temperature than the molten or liquid component. In other words, the polymer in this case consists of at least two components that are fed to the molten conductor together or separately.
[0009] The present invention further relates to a method of operating an extrusion facility.
[0010] Typical molten conductors and extrusion dies are known from the state of the art of extrusion technology and can be implemented in various embodiments.
[0011] Extrusion dies with circular or ring-gap nozzle cross sections are known. For example, spiral mandrels are used to deliver the polymer melt from the supply unit into the circular die. These spiral mandrels have helical grooves on the outer or inner side of the mandrel or sleeve. Related to this are sleeve distributors or mandrel holders that can distribute the polymer melt evenly so that a film tube or profile can exit the extrusion die.
[0012] Furthermore, extrusion dies with a slot-shaped output cross section of the extrusion nozzle are also known. The purpose of the melt conductor in such extrusion dies is to deliver the polymer melt supplied by the supply unit to the nozzle outlet or extrusion nozzle as uniformly as possible, so that the required amount of polymer melt is available across the desired width at each nozzle outlet. The state of the art is melt conductor systems, particularly in the form of T-shaped distributors, fishtail distributors, or coat hanger distributors.
[0013] Extrusion dies with multiple individual outlet sections are also known. The purpose of the melt conductors in these extrusion dies is to deliver the polymer melt supplied by the feed unit as uniformly as possible to the nozzle outlet or extrusion nozzle. Depending on the application, these melt conductors can be configured as T-shaped distributors, coat hanger distributors, line distributors, channel distributors, step distributors, sleeve distributors, spiral mandrel distributors, or gap distributors.
[0014] Most known molten conductors have a multi-part structure in which at least two halves of the molten conductor are threaded together. Welded structures are also available. As the size of the extrusion die becomes larger, the size of the molten conductor also becomes larger, which causes more problems with the pressure inside the die due to shear stresses of the polymer melt and consequently increases stress on the components, especially those that conduct the polymer melt. This places limitations on the structure and size of the extrusion die, especially when products with small cross-sectional areas are being extruded.
[0015] In either case, such molten conductor is used to uniformly distribute or combine a polymer melt that is substantially continuously supplied from a supply unit from an input side of the molten conductor having a cross-sectional area of the entire input section to an output side of the molten conductor having a cross-sectional area of the entire output section that is substantially varied in terms of geometry and spacing relative to the cross-section of the entire input section.
[0016] Therefore, the challenge of a melt distributor in the form of a melt conductor is to provide a larger overall cross-section of the downstream polymer melt at the melt distributor's output than that of the upstream melt conductor. In other words, the polymer melt must be uniformly distributed from a first overall cross-section to a second overall cross-section with a wider width. In this case, the melt channel cross-section of each output section does not necessarily have to be linear, as in the case of a slit die at the output, but can also be arc-shaped or circular, as in the case of a circular die at the output. In either case, the total circumference of the second overall cross-section, i.e., the sum of the total circumferences of the melt channels at the output side of the melt conductor, is much greater than the total circumference of the first overall cross-section at the input side of the melt conductor.
[0017] In contrast, the challenge of a melt conductor in the form of a melt mixer is to provide a polymer melt downstream of the output side of the melt distributor with a smaller overall output cross-section than is delivered to the upstream melt conductor. In other words, the polymer melt must be uniformly guided and mixed from a first overall throughput cross-section to a second overall throughput cross-section having a substantially smaller overall cross-sectional area, and again, the cross-section of each output melt channel is not necessarily linear.
[0018] In principle, the polymer melt is continuously fed to the input side of the melt conductor by at least one feed unit, in particular at least one extruder, and is then directed to the melt conductor. At the output side of the melt conductor, the polymer melt is at least indirectly sprayed to continuously produce the extruded product.
[0019] For example, DE 2114465 A1 discloses an apparatus for uniformly distributing thermoplastics from at least one extruder head nozzle to several blow heads or pointed heads, which has a large distributor block in which a number of boreholes and additional bolts are introduced for implementing melt ducts and deflection means within the large distributor block.
[0020] European Patent No. 0197181 describes a method for manufacturing a composite injection molding distributor, which has different branches for transferring melt from a common inlet opening to multiple outlet openings. The injection molding distributor consists of two plates with opposite surfaces, made of tool steel, screwed together, and these surfaces have matching grooves to form melt channels within the melt distributor.
[0021] German Patent Application No. DE 19703492 A1 discloses a melt distributor for extruded plastic melt, which splits the melt after it leaves the extruder nozzle into several individual strands for different processing tools. The melt distributor comprises a feed channel and a connected carbine with distributor channels, the number of distributor channels corresponding to the number of processing tools, and the centers of the openings of the distributor channels formed in the carbine are arranged in a circle. This ensures that the plastic melt is supplied to all processing tools with as uniform a temperature profile as possible.
[0022] Whenever a "molten conductor" is mentioned in this patent application, this refers to a melt conductor of an extrusion system that has a nozzle output for the original extrusion product itself or is adapted to feed a shaped extrusion nozzle. That is, a melt conductor that is part of an extrusion die of the extrusion system is referred to. The phrase "for an extrusion die of an extrusion system" in the claims is not intended to indicate that the extrusion die or system is necessarily part of the respective claim; instead, only compatibility is disclosed. Furthermore, the phrase "for an extrusion system" is not intended to mean that the system is necessarily part of the respective claim. Summary of the Invention
[0023] The present invention is based on the problem of further developing molten conductors and overcoming their drawbacks, in particular the problem of further developing extrusion dies, extrusion installations and corresponding methods, in particular for operating such extrusion installations.
[0024] According to the present invention, this problem is solved by a molten conductor having the features of independent claim 1. Optional advantageous further developments of the molten conductor result from dependent claims 2 to 13. Furthermore, the object of the present invention is achieved by an extrusion die according to claim 14. An advantageous further extrusion die development results from dependent claim 15. The problem of the present invention is further achieved by an extrusion installation according to claim 16. Furthermore, the problem of the present invention is achieved by a method for operating the installation according to claim 17.
[0025] In a first aspect of the invention, the subject is a melt conductor for an extrusion die of an extrusion installation, in particular a melt distributor or melt mixer, A fused conductor block with a multi-channel system; the multi-channel system is three-dimensionally arranged inside the fused conductor block and has at least one input and at least one output for the polymer melt; Between an input part and an output part fluidly connected to the input part, several branches arranged behind each other and several levels of further branches are formed over several levels of separated melt channels, There are m melt channels at level a with x local cross sections and n melt channels at level b with y local cross sections, In this, if b>a, then n>m; the y-th local cross section of the b-th level melt channel is smaller than the x-th local cross section of the a-th level melt channel; In a designated direction of flow of the polymer melt, the a-level melt channels are oriented toward the input portion and the b-level melt channels are oriented toward the output portion such that the melt conductor acts as a melt distributor for the designated melt stream of the polymer melt; or In a designated direction of flow of the polymer melt, the melt channels of the a-th level are oriented toward the output portion and the melt channels of the b-th level are oriented toward the input portion so that the melt conductor acts as a melt mixer for the designated melt stream of the polymer melt; The solution is fused conductors.
[0026] Firstly, it is expressly pointed out that within the framework of this patent application, indefinite articles and numerals such as "1", "2", etc. are usually to be understood as indicating a minimum value, i.e. "at least one...", "at least two...", etc., unless it is explicitly clear from the context or it is obvious to a person skilled in the art or technically necessary that only "exactly one...", "exactly two...", etc. may be intended.
[0027] Furthermore, all numbers and all information relating to method and / or apparatus parameters should be understood in their technical sense, i.e. taking into account normal tolerances.
[0028] The use of restrictive language such as "at least" does not imply that "exactly one" is intended when simply stating "one," i.e., without using "at least," etc.
[0029] Below, some terms are explained.
[0030] A "molten conductor" is a component or assembly including a molten conductor block with a multi-channel system adapted to distribute and / or combine a polymer melt delivered to the molten conductor, depending on the embodiment of the multi-channel system. The molten conductor can be embodied solely as a melt distributor, distributing a designated polymer melt from at least one input onto multiple outputs. Furthermore, the molten conductor can be embodied solely as a melt mixer, combining a designated polymer melt from two or more inputs into a total number of outputs that is less than the number of inputs. Alternatively, the molten conductor can be embodied partially as a melt distributor and partially as a melt mixer, in any order, to distribute and combine a designated polymer melt as desired, and to allow the number of inputs and outputs to be selected as desired. The molten conductor is preferably at least partially manufactured by additive manufacturing.
[0031] A "fused conductor block" is a component of the fused conductor that entirely or partially houses the multi-channel system. The fused conductor block is preferably formed by additive manufacturing. It can be a mass or a substrate formed with a support structure, for example, in a skeletal structure. The support structure can be formed to ensure the static stability of the fused conductor block and further support the multi-channel system. If the fused conductor is embodied as a fused distributor, the term "fused conductor block" will be used below as a synonym for the fused conductor block. Similarly, the term "fused mixer block" will be used below as a synonym for the fused conductor block if the fused conductor is embodied as a fused mixer.
[0032] A "melt channel" is a substantially longitudinal portion of a multichannel system that conducts a polymer melt (or a melt stream of a polymer melt), which can extend exclusively longitudinally or linearly, or can have curvatures to achieve a three-dimensional embodiment of the multichannel system. A plurality of such melt channels are fluidly interconnected through branches and sub-branches, thereby forming a multichannel system, in which two or more melt channels can be arranged in series and / or in parallel to distribute and / or mix the polymer melt according to requirements made for the melt conductor. The melt channels extend from respective inputs to respective outputs fluidly connected to the inputs.
[0033] Each melt channel can be embodied as desired. For example, it is possible for the melt channel to have a substantially constant cross-section, i.e., a local cross-section of any shape extending between branches along the entire length of the melt channel. The local cross-section can have a substantially circular cross-section, a substantially oval or elliptical cross-section, and / or a substantially rectangular or square cross-section. Alternatively, cross-sectional shapes that deviate from known standard geometric shapes can be selected for the melt channel, especially at transition points between known standard shapes. Whenever a specific cross-sectional shape of a melt channel is mentioned within the framework of the present invention, it is intended that each melt channel has this substantially constant cross-sectional shape or local cross-section over the majority of its axial extension, preferably over 50% or more of the length of the respective melt channel, preferably over at least two-thirds of the length of the channel, and preferably over at least three-quarters of the length of the channel.
[0034] The melt channels arranged next to each other in series and fluidly interconnected through branches or sub-branches are described within the framework of this patent application as being divided into "levels" designated in ascending or descending alphabetical order, depending on the embodiment of the melt conductor and on the designated direction of polymer melt flow. The same applies to the branches and sub-branches, which are also designated by ascending or descending levels.
[0035] The "designated flow direction" of the polymer melt refers to the arrangement of the molten conductor in the extrusion equipment and the embodiment of the multi-channel system, where the flow direction is always from an input to an output fluidly connected to the input, regardless of whether the polymer melt is distributed and / or mixed in the multi-channel system. In particular, the designated flow direction of the polymer melt is from the input side to the output side of the molten conductor.
[0036] A "multi-channel system" is a channel structure within a molten conductor, preferably manufactured at least partially by additive manufacturing methods, that is integrated into the molten conductor block and extends three-dimensionally within it. A multi-channel system consists of multiple fluidly interconnected melt channels extending from at least one input to at least one output fluidly connected to the input, and that are fluidly interconnected via branches and sub-branches or via connecting ducts, depending on the embodiment of the molten conductor. The melt channels of a multi-channel system can be fluidly interconnected in series with each other or arranged in parallel. In a serial arrangement, at least one melt channel in the a-th level is fluidly connected to at least one melt channel in the b-th level via a branch or sub-branch, and the melt channel in the a-th level is located upstream or downstream of each melt channel in the b-th level in the designated direction of polymer melt flow, depending on the embodiment of the molten conductor as a distributor or mixer. In other words, the melt channel in the a-th level is fluidly connected to the melt channel in the b-th level via a branch or connecting duct. In contrast, some, preferably all, of the melt channels on one level are arranged in parallel.
[0037] The "input" of the multi-channel system is the input of the multi-channel system to the molten conductor block to which the polymer melt provided by the supply unit is delivered. In other words, the input is located on the input side of the molten conductor block.
[0038] In contrast, the "output" of a multi-channel system is the output of the multi-channel system from the molten conductor block, where the polymer melt exits after being directed, distributed, and / or combined through the molten conductor block. The output can be formed as a nozzle and thus can be a nozzle output. Alternatively or additionally, the output can be configured to feed an extrusion nozzle connected downstream of the molten conductor, thereby atomizing the polymer melt to at least indirectly produce the extruded product. Thus, the output is located on the output side of the molten conductor block.
[0039] Thus, the melt conductor block has an input side and an output side, the input side with the respective input portion being arranged downstream of the supply unit with respect to the designated flow direction of the polymer melt, and the output side with the respective output portion being arranged upstream of the extrusion nozzle or downstream of the input side with the respective input portion.
[0040] When the melt conductor is embodied as a melt distributor, the melt conductor has more outputs than inputs, with each input fluidly connected to multiple outputs, preferably via at least two levels of separated melt channels. To prevent disruption of the melt flow of a designated polymer melt, protect the multi-channel system from unwanted deposits, and maintain substantially constant shear stress within the multi-channel system, the overall cross-sectional area of all local cross sections of the melt channels in one level increases with each level. Meanwhile, the local cross-sectional area of each of the n melt channels in the bth level decreases compared to the local cross-sectional area of each of the m melt channels in the ath level. Meanwhile, the number of melt channels increases with each level, i.e., in ascending alphabetical order. In other words, the melt channels in the ath level are oriented toward the inputs, and the melt channels in the bth level are oriented toward the outputs, following the melt channels in the ath level in the designated direction of polymer melt flow. Correspondingly, the melt channel at the c-th level follows the melt channel at the b-th level in the designated direction of flow of the polymer melt, etc., and the melt channel at the c-th level is also oriented toward the output relative to the melt channels at the a-th and b-th levels. The melt channel at the b-th level is oriented toward the input relative to the melt channel at the c-th level. The melt channel at the a-th level is divided into at least two melt channels at the b-th level, which are further subdivided into at least two melt channels at the c-th level, etc. Thus, the melt channel levels increase in alphabetical order, and the number of melt channels increases with each level along the designated direction of flow of the polymer melt.
[0041] When the melt conductor is a melt mixer, the melt conductor has more inputs than outputs, preferably because at least two inputs are fluidly connected to a smaller number of outputs via at least two levels of joined melt channels. The overall cross-sectional area of all local cross sections of the melt channels in one level decreases with decreasing level to prevent the melt flow of the designated polymer melt from being interrupted and to maintain substantially constant wall shear stress in the multichannel system. Meanwhile, the local cross-sectional area of each of the n melt channels in the bth level increases compared to the local cross-sectional area of each of the m melt channels in the ath level. Meanwhile, the number of melt channels decreases with each level, i.e., in descending alphabetical order. In other words, using the example of three levels of melt channels in a multichannel system, the melt channels in the cth level are oriented toward the inputs, and the melt channels in the bth level are oriented toward the outputs, following the melt channels in the cth level in the designated direction of polymer melt flow. Correspondingly, the melt channels in the a-th level follow the melt channels in the b-th level in the designated direction of polymer melt flow and are further oriented toward the output relative to the melt channels in the c-th and b-th levels. In contrast, the melt channels in the b-th level are oriented toward the output relative to the melt channels in the c-th level. This means that at least two melt channels in the c-th level are joined to fewer melt channels in the b-th level, which in turn are joined to fewer melt channels in the a-th level. Thus, the alphabetical order of the melt channel levels increases, and the number of melt channels increases between levels in the opposite direction to the designated direction of polymer melt flow.
[0042] It is further contemplated that the melt conductor may be embodied partially as a melt distributor and partially as a melt mixer. For example, the first melt channel on level a may be split into at least two melt channels on level b, which may then be split into at least two melt channels on level c, thereby first distributing the polymer melt to the next level. Next, at least two melt channels on level c may be recombined into a smaller number of melt channels on level b', which may then be recombined into melt channels on level a', and so on, such that the polymer melt is combined level by level. Depending on the requirements of the polymer melt and the extrusion product to be produced therefrom, the reverse order in which the first melt channels are joined and then separated, as well as any desired combination of distribution and combination, are contemplated.
[0043] The expression "oriented toward" within the framework of the present invention should be understood as the arrangement of the melt channels and / or branches or sub-branches of the first level relative to the further levels. For example, if a multi-channel system has melt channels in levels a, b, and c, where the a level is located directly at the input of the molten conductor block and the c level is located directly at the output of the molten conductor block, and the b level between the a and c levels is in the designated direction of polymer melt flow, the melt channels in level a are oriented toward the input compared to the melt channels in levels b and c. The melt channels in level c are oriented toward the output compared to the melt channels in levels a and b. As a result, the melt channels in level b are oriented toward the output compared to the melt channels in level a, and toward the input compared to the melt channels in level c.
[0044] By "extending three-dimensionally," it should be understood that the multi-channel system can be formed in the fused conductor block with up to six different degrees of freedom. In other words, the melt channels of the multi-channel system can extend vertically upward and / or downward and / or horizontally to the left and / or right and / or forward and / or backward. Regardless of how the multi-channel system is implemented in the fused conductor block, at least three of the six degrees of freedom are always used. For example, if a melt channel at level a extending vertically downward is split into two melt channels at level b at a common level through a branch at a substantially 90° angle, the split melt channels would extend horizontally, for example, to the left or right, starting from the melt channel at level a. Thus, even with such a simple subdivision of the melt channels, three degrees of freedom are already used. However, if one of the melt channels branches so that at least one of the split melt channels extends partially at an angle relative to that level, the fourth and / or fifth degrees of freedom are used. In addition, one of the melt channels on the b-th level can also be partially directed opposite to the melt channel directed vertically downward on the a-th level, i.e., in the opposite direction of the polymer melt flow, so that a sixth degree of freedom is also used. Furthermore, multi-channel systems or curved embodiments of melt channels and / or further branches in the space are conceivable, so that several degrees of freedom can be used simultaneously.
[0045] A "branch" or "sub-branch" according to the present invention is a node where a melt channel splits into at least two melt channels, regardless of the direction of polymer melt flow. A sub-branch is a branch from the second level downward. In a melt distributor, a melt channel at level a splits into two or more melt channels at level b through a branch. The melt channel at level b subsequently splits into two or more melt channels at level c through a branch into two or more melt channels. In contrast, in a melt mixer, a branch or sub-branch functions as a junction, where two or more melt channels at level b are joined or combined to form a melt channel at level a or a smaller number of melt channels at level a.
[0046] The polymer melt continuously fed to the melt distributor or multi-channel system of the melt distributor block by the melt conductor in the form of a melt distributor can be distributed across multiple outputs so that the polymer melt can be supplied to these outputs or output channels with substantially equal shear stress. That is, the multi-channel system is preferably embodied so that the polymer melt always has a uniform melt profile. Furthermore, in this way, it is achieved that the polymer melt is particularly uniformly distributed across the output side of the melt distributor block and therefore can be particularly uniformly supplied downward in the extrusion space adjacent to one of the output channels, i.e., particularly at the collection space and / or inlet of the extrusion nozzle.
[0047] The expression "equal shear stresses" according to the present invention essentially refers to the wall shear stresses between the walls of the multichannel system and the polymer melt conducted in each melt channel, in particular in all branching stages or all levels of melt channels, which shear stresses are substantially equal or constant or approximately equal or constant and deviate from each other by less than 30%, preferably less than 20%, particularly preferably less than 10%.
[0048] The polymer melt continuously fed into the multi-channel system of the melt mixer or melt mixer block by the melt conductor in the form of a melt mixer can be joined with a smaller number of outputs so that the polymer melt can be supplied at these outputs with substantially equal shear stress. Again, the multi-channel system is preferably embodied in such a way that the polymer melt always has a uniform melt profile at the outputs. Furthermore, in this way, it is achieved that the polymer melt is particularly uniformly joined at the output side of the melt distributor block, and can therefore also be supplied in a targeted manner downwards to the extrusion space adjacent to the output channels, i.e., in particular the collection space and / or inlet of the extrusion nozzle.
[0049] This is achieved primarily through the varying cross-sectional areas of the melt channels from one level to the next, as well as the branches and sub-branches, or junctions, located between the levels of the melt channels.
[0050] In the case of a melt distributor, the cross-sectional area of each melt channel in one level decreases with increasing level and in the designated direction of flow of the polymer melt, and the total melt channel increases with each increasing level so that the melt flow is distributed between the levels in the designated direction of flow.
[0051] In the case of a melt mixer, the cross-sectional area of each melt channel at one level increases with decreasing level and in the designated direction of flow of the polymer melt, and the total melt channel decreases with each level so that the melt flow joins between levels in the designated direction of flow.
[0052] Surprisingly, it has been shown that a specific geometric ratio between a first melt channel and a second melt channel adjacent to a designated direction of flow of the polymer melt results in a substantially constant shear stress within the multi-channel system. Thus, preferably, the circumference and cross-sectional area of at least two melt channels originating from and branching off from the same melt channel are: Dimensioned according to TIFF0007737365000001.tif19170, U1 is the first circumference, A1 is the first cross-sectional area of the common melt channel, U2 is the second circumference, A2 is the second cross-sectional area of one of the origin melt channels, and n K is the total number of origin melt channels, x is greater than or equal to -0.5, preferably at least 0.5, preferably at least 0.75, and x has a value of at most 4, preferably at most 2.5, more preferably at most 1.5. Surprisingly, it has been shown that values of x between 0.6 and 2 are advantageous.
[0053] In the case of a melt conductor embodied as a melt distributor, the melt channel is divided into at least two melt channels arranged downstream thereof, U1 is a first circumference, A1 is a first cross-sectional area of the common melt channel arranged further upstream, U2 is a second circumference, and A2 is a second cross-sectional area of one of the divided melt channels arranged further upstream, relative to the designated flow direction of the polymer melt and therefore the flow direction of the downstream level melt channel.
[0054] In the case of a melt conductor embodied as a melt mixer, at least two melt channels are preferably combined to form a common melt channel located downstream thereof, where U1 is a first circumference, A1 is a first cross-sectional area of the common melt channel located further downstream, U2 is a second circumference, and A2 is a second cross-sectional area of one of the at least two melt channels located further upstream, relative to a designated flow direction of the polymer melt and thus the flow direction of the upstream melt channel.
[0055] The number of separated melt channels at one level, n, depends on the diameter of the melt channel at this branching level. K is selected to reduce shear stress variations within the multi-channel system and the associated risk of possible melt flow blockage.
[0056] This relationship is particularly advantageous because, in practice, the geometry of each melt channel does not remain constant at all points along its entire length. This geometric relationship is particularly advantageous for simple cross-sectional geometries of the channels of a multi-channel system. Construction of a multi-channel system using such a relationship has also been shown to be advantageous for melt channel cross-sections that are substantially symmetrical and whose cross-sectional width is not many times greater than their cross-sectional height.
[0057] In contrast, in melt channel cross-sectional geometries where the narrowest and widest parts of a local cross section are close to each other, it may be advantageous to establish only a relationship between the cross-sectional area of the divided melt channel and the cross-sectional area of the divided melt channel, depending on the number of divided melt channels. In circular cross sections, the widest and narrowest parts of the local cross section of each melt channel are identical and correspond to the diameter. The observation of the planar relationship described below is particularly advantageous in melt channels where the difference between the narrowest and widest parts is less than 10 times, preferably less than 5 times, and particularly preferably less than 2.5 times.
[0058] Preferably, the cross section of at least two branching melt channels originating from the same melt channel is: A2=A1*(1 / n K ) 2 / y The dimensions are determined according to where A1 is the first cross-sectional area of the common melt channel, A2 is the second cross-sectional area of one of the branch melt channels, and n K is the total number of divided melt channels, y has a value of at least 2, preferably at least 2.5, more preferably at least 2.85, and y has a value of at most 7, preferably at most 5, more preferably at most 3.35. Surprisingly, values of 2.5 to 5 for y have been shown to be advantageous.
[0059] When the melt conductor is embodied as a melt distributor having a substantially circular melt channel, the melt channel is divided into at least two melt channels arranged downstream thereof, A1 is a first cross-sectional area of the common melt channel arranged further upstream, and A2 is a second cross-sectional area of one of the at least two divided melt channels arranged further downstream with respect to the designated flow direction of the polymer melt and thus the downstream level melt channel.
[0060] In a melt conductor embodied as a melt mixer having substantially circular melt channels, at least two melt channels are preferably combined into a common melt channel located downstream thereof, where A1 is a first cross-sectional area of the combined common melt stream located further downstream, and A2 is a second cross-sectional area of one of the at least two melt channels located further upstream relative to the designated direction of flow of the polymer melt and thus the downstream melt channel.
[0061] When the a-level melt channels and the b-level melt channels are embodied according to this geometric relationship, a substantially constant shear stress inside the multi-channel system can be achieved. Furthermore, there is a material-independent correlation between the fluidly interconnected channels of the multi-channel system, which significantly reduces shear stress fluctuations and the risk of melt flow interruption. This correlation between cross-sectional geometries is particularly suitable for cross-sections whose width is many times larger than their height.
[0062] Preferably, each multi-channel melt channel has a local cross-sectional shape that deviates from a circular shape in at least some portions. The local cross-sectional shape of the melt channel can be embodied as desired, with the specific form depending on the characteristics of the polymer melt and the requirements made for the extruded product. For example, elliptical, oval, drop-shaped, jaw-shaped, and / or oval cross-sections may be particularly advantageous depending on the application. Furthermore, melt channel embodiments have the advantage of preventing accumulation of the polymer melt within the multi-channel system. By at least partially additively manufacturing the multi-channel system, essentially any known standard geometric shape can be produced as the local cross-sectional shape, and the present invention is not expressly limited to standard geometric shapes of the melt channel cross-section. In other words, the free-form surface of the melt channel wall can be shaped in any way, which ideally guides the specified polymer melt through the multi-channel system with a substantially uniform shear stress.
[0063] The present invention includes the technical teaching that a fused conductor block has a first multi-channel system and a second multi-channel system, and particularly a third, fourth, or fifth multi-channel system. Six or more multi-channel systems formed at least partially by additive manufacturing within the fused conductor block are also contemplated. Different multi-channel systems can conduct identical but different, or partially identical and partially different, polymer melts, for example, to produce multilayer or at least partially overlapping film webs or filaments. Furthermore, depending on the material requirements and properties, different polymer melts can be conducted, joined, and distributed within the multi-channel systems to produce extruded products. It is also possible to produce individual filaments, particularly individual endless filaments, from the polymer melts of different multi-channel systems. The filaments can be formed from different components, i.e., the polymers are melted in various mixing ratios, and the components are arranged adjacent to each other, for example, in respective filament layers, sheets, and / or segments.
[0064] In one embodiment, the multi-channel systems are fluidly separated, each with at least one input and at least one output for the polymer melt. Several fluidly separated multi-channel systems can be produced, such as two or more film webs and / or two or more layered film webs, particularly fluidly separated multi-channel systems with different film layers when different polymer melts are directed through the molten conductor. Furthermore, multiple filaments with similar or different material properties can be produced and processed to form nonwoven fabrics. Nonwoven fabrics consist of multiple individual filaments, preferably 20 to 10,000 individual filaments per meter of fabric width. The output of each multi-channel system can be configured to atomize the polymer melt to form filaments. An extrusion nozzle downstream of the molten conductor block can also be used to produce the filaments, which are then used to produce the nonwoven fabric.
[0065] It is also possible to produce multiple individual filaments, each made from a different polymer or polymer melt. Such filaments can be embodied in different ways, for example, processed to form a nonwoven fabric or a yarn. The filaments can have, for example, a substantially circular cross-sectional shape, with a first strand arising from a first polymer melt in a first multi-channel system being covered by a second strand arising from a second polymer melt in a second multi-channel system. It is also possible to join more than two strands, and the strands of polymer melts can be joined as desired, for example, by appropriately arranging the outputs of the respective multi-channel systems adjacent to each other in layers, sheets, and / or segments.
[0066] Alternatively, the first multi-channel system may have at least one junction with a second multi-channel system. In this way, composite materials or composite products can be produced. For example, a substantially molten polymer melt can be conducted through the first multi-channel system, and a second polymer melt different from the first polymer melt, or a filler, reinforcing agent, or other additive, present at least partially in melt form, is conducted through the second multi-channel system, where these additives are mixed at their respective junctions with the first polymer melt conducted through the first multi-channel system. Thus, at least two additives are initially mixed in the region of each junction and then combined during the atomization and subsequent cooling of the melt. That is, mixing is performed. The purpose of the mixing is to modify the properties of the joined materials or melts for the application of the extruded product.
[0067] In this context, it is also possible to conduct a recycled polymer through a first multi-channel system and a new polymer of the same type through a different multi-channel system.The two melt streams of the same polymer type are then mixed in a mixing ratio that can be selected as desired from a process engineering point of view, depending on the desired properties of the final product.
[0068] Depending on the requirements of the extruded product, the various melts can be mixed or joined relatively quickly, for example, briefly after entering the respective multi-channel systems. This is particularly advantageous when particularly good mixing of the first and second polymer melts is desired, or when the properties of a specified composite polymer melt flowing through the multi-channel system are to be improved. Alternatively, the melts can be joined in the respective multi-channel systems at a relatively late stage, for example, just before reaching the output of the respective multi-channel systems. This is particularly desirable when demixing of the flow components would otherwise occur in the longer channel cross sections.
[0069] In one embodiment, each multi-channel system comprises a plurality of outputs adapted to direct the polymer melt into a collection chamber for delivery to an extrusion nozzle, in other words, in such an embodiment, the outputs are arranged across a specific width of the molten conductor, in particular the molten conductor block, and terminate in the collection chamber.
[0070] The outputs can be spaced apart transversely to the direction of the designated melt stream output. They can be formed on a common line on the output side of the melt conductor block, which can be straight or curved. The outputs can also exit the melt conductor block in one or more planes, with the first and one or more additional planes being arranged transversely to the direction of the designated melt stream output, overlapping, partially overlapping, or alternating with one another. Particularly in the production of film webs, plates, or blown film, whether the polymer melt is fed to a collection chamber or directly to an extrusion nozzle, an overlapping arrangement of two or more planes is advantageous because it allows for the production of a continuous, relatively homogeneous extrusion product with no or negligible seams, particularly in terms of width.
[0071] In this context, a "collection chamber" is a substantially hollow space in which the polymer melt combined and / or distributed via the melt conductor is collected and delivered to the extrusion nozzle. In other words, the collection chamber can be an extrusion space or a nozzle space for delivery to the extrusion nozzle. The collection chamber can also be embodied to deliver to two or more extrusion nozzles, each of which is delivered upstream in a designated extrusion direction of the polymer melt.
[0072] It is also possible for the collection chamber to be divided into two or more collection chamber segments, which can have any shape and size. Thus, the extrusion die has several collection chambers or collection chamber segments, each of which feeds one or more extrusion nozzles.
[0073] The collection chamber is preferably integrated with the molten conductor, in particular with the molten conductor block. Such a structure can be relatively easily realized due to the additively manufactured shape of the molten conductor, in particular with the molten conductor block. Furthermore, the area of the collection chamber can be provided with means for receiving fastening and / or connecting elements of the respective extrusion nozzle, which can also be manufactured at least partially additively.
[0074] It is expressly pointed out that a device having the features of the above paragraphs in itself represents an independent aspect of the invention, independently of the above independent claims. Accordingly, combinations of features that are understood to be advantageously disclosed independently are as follows:
[0075] A molten conductor, in particular a melt distributor or melt mixer for an extrusion die of an extrusion equipment having a melt conductor block with a multi-channel system, the multi-channel system being arranged in the melt conductor block with a three-dimensional extension and having one or more input sections and multiple output sections, the multiple melt channels feeding through the output sections into a collection chamber, which is adapted to feed the molten conductor into an extrusion nozzle of the extrusion die.
[0076] More preferably, the fused conductor, particularly the fused conductor block, has a hollow chamber system with at least one hollow chamber, which is spatially arranged between the divided melt channels of each multi-channel system. In other words, the fused conductor block has a base body with a hollow chamber, preferably multiple hollow chambers. The multi-channel system can be surrounded by the hollow chamber system so that the hollow chambers of the hollow chamber system are operably connected to the multi-channel system. This is a particularly easy way to ensure a lightweight structure of the fused conductor, particularly the fused conductor block.
[0077] Such a hollow chamber system allows the fused conductor block to be manufactured with significantly reduced weight while still having adequate rigidity, which greatly simplifies the handling of the fused conductor block, for example, which is advantageous for replacement and maintenance work, etc. Furthermore, the fused conductor block implemented by the hollow chamber system saves material and significantly reduces the manufacturing cost of the fused conductor.
[0078] In addition to the multiple polymer-containing melt channels of a multi-channel system, it is particularly advantageous that the fused conductor block can be provided with additional cavities or chambers, allowing the substrate of the fused conductor block to perform additional functions. In particular, individual hollow chambers of a hollow chamber system, or portions thereof, can be equipped, and in particular filled, with insulation or the like.
[0079] It is also conceivable to at least partially embody a hollow chamber system so that a medium can be guided through the hollow chamber. In particular, it is conceivable to guide a temperature control medium for heating or cooling a multi-channel system operably connected to the hollow chamber system through the hollow chamber system. In this way, temperature control of the specified polymer melt and uniform component temperatures of the molten conductor, particularly the molten conductor block, can be achieved.
[0080] The hollow chamber system can be divided into several segments, each of which can comprise one or more hollow chambers. In this way, several different temperature control media can be supplied. Advantageously, a multi-channel system can be embedded in the hollow chamber system, allowing additional support of the melt channel walls by contoured elements such as webs, ribs, or other material structures in the hollow chamber system.
[0081] For example, the melt channel walls of two or more adjacent melt channels in space can be stabilized to each other by a hollow chamber system, making the multi-channel system resistant to very high polymer melt pressures despite the lightweight structure of the melt conductor block.
[0082] It will be appreciated that such hollow chamber systems may be constructed as desired, for example, as a grid structure, a square structure, a spherical structure, a hemispherical structure, an arc-shaped structure, and the like.
[0083] In a preferred embodiment, the hollow chamber system has a honeycomb structure, i.e., the hollow chamber is at least partially embodied in the form of a honeycomb. The honeycomb structure is particularly effective at absorbing and dissipating forces acting on the fused conductor, particularly the fused conductor block. Furthermore, the honeycomb preferably has six or more side walls, providing an advantageous number of wall surfaces on the inside of the fused conductor block, allowing for connection possibilities, such as through-holes, channels, etc., for connecting to multiple adjacent honeycombs. This allows for a particularly advantageous lightweight structure of the fused conductor block combined with high stability.
[0084] The hollow chamber system advantageously found in the fused conductor block of the present invention can be provided in a number of ways, but is particularly effective when manufactured by additive manufacturing, which allows for the fabrication of a variety of hollow chamber structures within the fused conductor block in a very simple manner.
[0085] It is expressly pointed out that a device having the features of the above paragraphs, taken in itself, represents an independent aspect of the invention, independently of the above independent claims. Accordingly, the independently advantageous disclosed combinations of features are as follows:
[0086] A molten conductor, particularly a melt distributor or melt mixer for an extrusion die of an extrusion equipment having a melt conductor block with a multi-channel system, the multi-channel system being arranged within a melt conductor block with a three-dimensional extension, the molten conductor, particularly the melt conductor block, having a hollow chamber system with multiple hollow chambers spatially arranged between the melt channels of the multi-channel system, and through holes preferably being arranged between adjacent hollow chambers so that a temperature control fluid can flow through at least the hollow chambers that are in contact with the melt channels.
[0087] Preferably, the multi-channel system has a global machine direction through the melt conductor block leading from the input to the output of a designated melt flow of plastic melt, and the divided melt channels extend partially opposite to the global machine direction when the local machine directions are projected onto the global machine direction.
[0088] "Global machine direction" refers to the arrangement of molten conductors, particularly molten conductor blocks, in an extrusion installation, where the global machine direction extends along a designated direction of flow between a supply unit and, as the case may be, an extrusion nozzle or nozzle output on a molten conductor block. That is, the global machine direction is the spatial extension of molten conductors, particularly molten conductor blocks, in an extrusion installation, taking into account the input and output sides of a designated polymer melt multi-channel system.
[0089] The term "local machine direction" can deviate from the global machine direction, and refers to the local orientation of each melt channel in a multi-channel system, particularly relative to the global machine direction. The local machine direction extends coaxially with the longitudinal axis of the melt channel in the designated direction of flow of the polymer melt. In a particularly simplified case, when a multi-channel system has an input section on the input side of the melting conductor block and an output section on the output side of the melting conductor block opposite the input side, fluidically connected thereto and coaxially arranged, the local machine direction can preferably partially coincide with the global machine direction. The orientation of the melt channels in space, and therefore the local machine direction, can in this case be at least partially coaxial with the global machine direction.
[0090] The multi-channel system is formed so that it extends three-dimensionally inside the molten conductor or molten conductor block, respectively, so that the local machine direction deviates regularly from the global machine direction. Since the multi-channel system can be formed using all six degrees of freedom, an inclined arrangement of the individual melt channels with respect to the global machine direction is possible. It is also conceivable to partially provide a local machine direction that extends opposite to the global machine direction, which may be advantageous, particularly for saving installation space.
[0091] Therefore, in a specific example of an embodiment, the melt channels of a multi-channel system can be directed back toward the approximate input side of the molten conductor, particularly the molten conductor block. Thus, the advantage of directing the local machine direction of the melt channels opposite to the global machine direction lies in the fact that any desired arrangement of the melt channels relative to the global machine direction is possible, allowing the molten conductor or molten conductor block to be embodied in a way that saves a large amount of installation space. Furthermore, the melt channels can be arranged to bypass connecting or fastening elements, particularly screws, threads, etc., as desired.
[0092] It is expressly pointed out that a device having the features of the above paragraphs, taken in itself, represents an independent aspect of the invention, independently of the above independent claims. Accordingly, the independently advantageous disclosed combinations of features are as follows:
[0093] A molten conductor, particularly a melt distributor or melt mixer for an extrusion die of an extrusion equipment having a molten conductor block with a multi-channel system, the multi-channel system being arranged within the molten conductor block with a three-dimensional extension, the multi-channel system having an input section and an output section, the input section being fluidly connected to the output section via a plurality of split and / or combined melt channels each having a local machine direction, the molten conductor block having a global machine direction from the input side of the molten conductor block to the output side of the molten conductor block, the split melt channels of the multi-channel system extending partially opposite to the global machine direction when the local machine direction is projected onto the global machine direction.
[0094] The melt channels can extend three-dimensionally in space as desired. Thus, each channel can also extend inclined in space, i.e., at an angle relative to the global machine direction. Furthermore, as the melt channels extend along the local machine direction, they can exhibit changes in direction or bends with a radius of curvature greater than, and preferably many times greater than, the local diameter of the melt channel. This can help avoid buildup in the multi-channel system and provide more uniform guidance of the polymer melt.
[0095] Preferably, the change in direction is located between two branches and / or sub-branches of the melt channel. In other words, each curved section is formed between the input and output of each melt channel. The same applies to branches and / or sub-branches that equally exhibit a change in direction or a curved section with a bend radius larger, preferably several times larger, than the local diameter of the melt channel. Of course, each melt channel, each branch and / or sub-branch can also have more than one change in direction or a curved section, and straight sections can also be formed between the changes in direction.
[0096] Preferably, the fused conductor block further comprises medium channels, in particular for circulating fluid supply, in particular for temperature control, and / or for electrical wires and / or measuring devices.
[0097] In this context, the term "media channel" refers to an additional channel system formed in addition to and fluidically separated from the multi-channel system, but can be formed into a structure similar to the multi-channel system. This means that the media channel can also extend three-dimensionally through the molten conductor block and have input and output ports fluidly connected thereto. The media channel can extend spatially separated between the melt channels of the multi-channel system and be operatively connected thereto. The media channel can be formed, for example, to conduct a medium, particularly a temperature-control medium. In addition to hollow chamber systems, the media channel can be a separate channel or channel system that saves space and allows interaction with a designated polymer melt conducted within the melt channel. Furthermore, the media channel or another media channel can be designed to conduct electrical wires and / or measurement units, such as a sensor system with corresponding power supply lines. Through additive manufacturing, the multi-channel system can be formed to bypass the media channel (which can also be additively manufactured), or vice versa. The support structures described above can equally be used to achieve static stability of the media channel.
[0098] It is expressly pointed out that a device having the features of the above paragraphs, taken in itself, represents an independent aspect of the invention, independently of the above independent claims. Accordingly, the independently advantageous disclosed combinations of features are as follows:
[0099] A molten conductor, in particular a melt distributor or melt mixer for an extrusion die of an extrusion installation having a molten conductor block with a multi-channel system, the multi-channel system extending three-dimensionally inside the molten conductor block, the molten conductor, in particular the molten conductor block, having media channels spatially arranged between the melt channels of the multi-channel system, in particular for circulating fluid supply, in particular for temperature control, and / or for electrical wires and / or for measuring devices.
[0100] In one embodiment, the melt conductor block has a static functional element for at least indirectly influencing the designated polymer melt. A "static functional element" is at least one substantially stationary element or component disposed in or within the multi-channel system that interacts with the designated polymer melt. The static functional element influences the designated polymer melt so that its properties, particularly its flow characteristics, remain substantially the same or preferably improve from the input to the output. In particular, the static functional element can make the melt temperature of the melt stream more uniform. Furthermore, melt stream homogenization can prevent polymer melt sedimentation and / or demixing in the multi-channel system.
[0101] The static functional element is preferably a static mixing element. The mixing element is preferably disposed inside the multichannel system or in the melt channel of the multichannel system, and is preferably manufactured, at least partially by additive manufacturing of the multichannel system. The mixing element can be ramp-shaped, rod-shaped, curved, etc., and is primarily designed to mix and homogenize a specified polymer melt. Due to shear stresses within the polymer melt, the melt stream has a different flow rate in the melt channel, which decreases in the direction from the central axis of the melt channel to the wall of the melt channel. In this context, the static functional element, particularly the static mixing element, homogenizes the melt strands conducted inside the melt channel. For example, homogenization of the melt flow through the static mixing element just before the output of the multichannel system can be achieved by homogenizing it to the extrusion nozzle or a collection chamber arranged upstream of the extrusion nozzle.
[0102] The static mixing element is preferably positioned inside the melt channel between two branches or sub-branches. It is conceivable that a small local change in the cross section of the melt channel is formed in the region of the mixing element, particularly to improve the mixing effect. Preferably, a local widening of the melt channel is provided, which is formed according to the flow characteristics inside each melt channel, and the static mixer is formed inside the local widening portion. The melt channels preferably have substantially the same cross-sectional size and shape before and after the local widening portion of the melt channel, and a locally enlarged cross section is formed between the melt channels in the designated flow direction of the polymer melt. The change in cross section can be step-like and / or ramp-like. Furthermore, it is advantageous if, after the change in direction of the melt channel, the polymer melt or melt flow, respectively, is directed from the central axis of the respective melt channel toward the wall of the melt channel by a simple static mixing element.
[0103] It is expressly pointed out that a device having the features of the above paragraphs, taken in themselves, represents an independent aspect of the invention, independently of the above independent claims. Accordingly, the independently advantageous disclosed combinations of features are as follows:
[0104] A molten conductor, in particular a melt distributor or melt mixer for an extrusion die of an extrusion installation having a molten conductor block with a multi-channel system, the multi-channel system extending three-dimensionally inside the molten conductor block, and the molten conductor, in particular the molten conductor block, having static functional elements for at least indirectly influencing a designated polymer melt.
[0105] In a second aspect of the present invention, this problem is solved by an extrusion die for an extrusion installation for producing extruded products, the extrusion die comprising a molten conductor according to the above-described embodiment, the molten conductor being adapted to distribute and / or mix at least one polymer melt.
[0106] An "extrusion die" is an assembly of extrusion equipment comprising one or more molten conductors, each having one or more molten conductor blocks. The extrusion die is fed with a polymer melt, which is at least indirectly directed into the multi-channel system of the molten conductor or conductor blocks of the molten conductor. Upstream of the extrusion die, a feeding unit in the form of an extruder or the like is arranged for feeding the designated polymer melt. Downstream of the molten conductor or each conductor block, at least one extrusion nozzle, which may preferably be part of the extrusion die, is arranged. The extrusion nozzle has an extrusion nozzle output that is embodied for intermediate or final shaping of the extruded product.
[0107] Alternatively, each fused conductor block may already have an extrusion nozzle integrally connected thereto, or may be formed as an extrusion nozzle, or may assume the function of an extrusion nozzle so that a separate extrusion nozzle is not required. For this purpose, each output of the multi-channel system on the output side of the fused conductor block is appropriately shaped and dimensioned so that a designated atomization of the polymer melt occurs. In this case, the sum of all outputs of the fused conductor block is called the "extrusion nozzle output," and the extrusion nozzle output may be embodied as desired depending on the arrangement of the outputs relative to one another in terms of height and width. The extrusion nozzle output preferably has a width several times greater than its height.
[0108] The separate extrusion nozzle and the corresponding extrusion nozzle output, as well as the molten conductor, can also be manufactured at least in part by additive manufacturing methods, which are particularly uncomplicated methods for manufacturing various geometries of the extrusion nozzle and the extrusion nozzle output, as well as the respective connecting means for positively and frictionally connecting the extrusion nozzle to the molten conductor.
[0109] The extrusion nozzle of the extrusion die preferably has a width of more than 5,000 mm, preferably more than 6,000 mm, or even more than 8,000 mm. Additive manufacturing of the extrusion die, particularly the extrusion nozzle output, allows for previously impossible dimensions to be achieved. In particular, the extrusion nozzle and the extrusion nozzle output can be made larger. Furthermore, worn or defective parts can be replaced more quickly. Furthermore, the extrusion nozzle and / or the extrusion nozzle output can be multi-part, which allows for precise fitting of components with particularly low tolerances.
[0110] It is expressly pointed out that a device having the features of the above paragraphs, taken in themselves, represents an independent aspect of the invention, independently of the above independent claims. Accordingly, the independently advantageous disclosed combinations of features are as follows:
[0111] A molten conductor, in particular a melt distributor or melt mixer for an extrusion die of an extrusion installation having a molten conductor block with a multi-channel system, the multi-channel system extending three-dimensionally inside the molten conductor block, and the molten conductor, in particular the molten conductor block, having a width of more than 5,000 mm, preferably more than 6,000 mm or more than 8,000 mm.
[0112] In this regard, additional combinations of features that are disclosed as independent and advantageously independent are as follows:
[0113] 1. An extrusion die for an extrusion installation for producing extruded products, comprising 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.
[0114] In a third aspect of the present invention, this problem is solved by an extrusion installation for producing extruded products, which includes an extrusion die of the type described above. The extrusion installation is specifically designed to process a polymer melt and produce the extruded product. The polymer melt is fed to the extrusion installation by a supply unit, which may include a silo and / or an extruder. The advantage of such an extrusion die is that, due to its manufacturing method, the molten conductor, the molten conductor block, any extrusion nozzles present, and / or any extrusion nozzle outputs present in the nozzles can be easily and quickly replaced, for example, for repair and / or maintenance purposes. Furthermore, since the extrusion die can have any desired shape and size, especially any width, extrusion products can be produced in oversized, especially wide widths. Furthermore, a multi-part embodiment of the molten conductor, with several molten conductor blocks switched in parallel or series, makes it possible to produce extrusion products with dimensions, especially wide widths, that were previously impossible.
[0115] The extrusion equipment with the molten conductor of the present invention can be embodied as an apparatus for producing filaments or fibers. Such an apparatus generally has a dot-shaped polymer melt output in an extrusion die or conductor block of the molten conductor, with several small nozzle holes formed on the output side. As an endless filament, the fiber forms, for example, a nonwoven fabric, a monofilament, a multifilament, or a small tape. During this process, the molten conductor of the present invention is advantageously used as a melt distributor in a molding extrusion die to distribute the polymer melt.
[0116] In particular, the molten conductor according to the invention can be used in an apparatus for producing nonwoven fabrics made of endless filaments (called a spunbond line), which essentially consists of a spinning device for spinning the filaments, a cooling device for cooling the filaments, a drawing device for drawing the filaments, a deposition unit, in particular a deposition filter belt, for depositing the filaments to form a nonwoven web, a solidification unit for solidifying the filaments of the nonwoven web, and a winding unit for winding up the nonwoven web.
[0117] The spinning apparatus essentially consists of at least one gravimetric or volumetric input unit for inputting and sending at least one polymer component to an extruder or feed unit, at least one extruder or one feed unit for compressing, melting, and conveying the polymer component, at least one melt filter, ideally acting as a screen exchanger with or without automatic cleaning, for filtering particles from the polymer melt, at least one melt and / or viscose pump for conveying the polymer melt, at least one melt conductor formed as a melt distributor for uniformly distributing the polymer melt substantially transversely to the global machine direction or "cross direction" (CD) of the machine, and optionally at least one additional melt conductor embodied as a melt distributor for further distributing the polymer melt transversely to the global machine direction but also perpendicular to the "cross direction" (CD), also referred to as the "machine direction" (MD) of the machine, one or more nozzle dies of an extrusion die for producing filaments from the polymer melt, and rigid and / or flexible piping for connecting the above-mentioned units. The melt conductor according to the present invention is particularly used as a melt distributor for distributing the polymer melt.
[0118] Likewise, the invention can be used in an apparatus for producing nonwoven fabrics made of endless ultrafine filaments (called a smelting and spraying plant) consisting essentially of at least one spraying device for producing and subsequently cooling the ultrafine filaments, a deposition unit, in particular a deposition roller, for depositing the ultrafine filaments to form a nonwoven web, a solidification unit for solidifying the filaments to form a nonwoven web, and a winding unit for winding up the nonwoven web.
[0119] The spinning apparatus essentially consists of at least one gravimetric or volumetric dosing unit for dosing and feeding at least one polymer component into an extruder or feed unit, at least one extruder or one feed unit for compressing and melting the at least one polymer component, at least one melt filter, ideally acting as a screen exchanger with or without automatic cleaning, for filtering particles from the polymer melt, at least one melt and / or viscose pump for building continuous pressure on the polymer melt, at least one melt conductor formed as a melt distributor for homogeneously distributing the polymer melt in the "cross direction" (CD) of the apparatus, and optionally at least one additional melt conductor embodied as a melt distributor for additionally distributing the polymer melt in the "machine direction" (MD) of the apparatus, a single or multi-part nozzle die of an extrusion die for producing ultrafine filaments from the polymer melt, and rigid and / or flexible piping for connecting the above-mentioned units. The melt conductor according to the present invention is particularly used as a melt distributor for distributing the polymer melt.
[0120] In another embodiment, the extrusion system according to the present invention, which includes the melt conductor according to the present invention, can be an apparatus for producing plates or flat films. Such apparatuses have in common that a linear polymer melt output is formed in an extrusion die, particularly in a melt conductor block of the melt conductor, so that the extruded product has at least one upper surface and one lower surface. The melt conductor is advantageously used as a melt distributor in the forming extrusion die to distribute the polymer melt.
[0121] In a further embodiment, the molten conductor according to the present invention can be used in an apparatus for producing a flat film (called a flat film line), comprising a unit for feeding a polymer melt, a slot die or die for producing a plate-shaped polymer melt stream, and a cooling roller unit.
[0122] The unit for providing a polymer melt essentially consists of at least one gravimetric or volumetric dosing unit for dosing and feeding at least one polymer component to an extruder, at least one extruder for compressing, melting, and conveying the at least one polymer component, at least one melt filter ideally acting as a screen exchanger with or without automatic cleaning for filtering particles from the polymer melt, optionally a melt and / or viscose pump for conveying the polymer melt, optionally a melt mixer for creating a multi-layered melt stream structure, a melt conductor embodied as a melt distributor for distributing the melt stream in the "cross direction" (CD), an extrusion nozzle shaped as a slot die for forming a sheet-like polymer melt stream, and rigid and / or flexible piping for connecting the above units. The melt conductor can be embodied as a melt distributor, a melt mixer, or a combination of both.
[0123] In another variant, the extrusion installation according to the invention with the melt conductor according to the invention can be embodied as an apparatus for producing pipes, profiles or piping. Such an apparatus has a polymer melt output, which generates the inner and outer surfaces of the extruded product by means of correspondingly shaped melt channel guides and / or auxiliary equipment. Advantageously, the melt conductor according to the invention is used as a melt distributor in a shaping extrusion die for distributing the polymer melt.
[0124] In another variant, the extrusion installation according to the invention having the melt conductor according to the invention can be embodied as an apparatus for producing a tubular film. Such an apparatus has an at least partially circular polymer melt output in an extrusion die including an annular gap, providing the extruded product with an inner and outer surface. The melt conductor according to the invention is advantageously used as a melt distributor in a shaping extrusion die for distributing the polymer melt.
[0125] In particular, the molten conductor according to the invention can be used in an apparatus for producing blown films (called a blow molding plant) which essentially consists of a unit for feeding the polymer melt, i.e. a feeding unit, a blow head for producing a tubular film, a take-off unit for taking off and stretching the tubular film in the transverse and longitudinal extrusion directions, and a cooling unit for cooling the tubular film.
[0126] The unit for supplying the polymer melt, i.e., the supply unit, essentially consists of at least one gravimetric or volumetric dosing unit for dosing and feeding at least one polymer component into an extruder, at least one extruder for compressing, melting, and conveying the at least one polymer component, at least one melt filter, ideally acting as a screen exchanger with or without automatic cleaning for filtering particles from the polymer melt, optionally a melt and / or viscose pump for conveying the polymer melt, and rigid and / or flexible piping for connecting the above-mentioned units with a blow head, which should be understood as an extrusion die according to the present invention having a melt distributor, in particular a spiral or plate distributor, and which includes a slot die with a spiral distributor, in particular a radial spiral distributor for forming a monolayer or multilayer annular polymer melt stream, and an expansion unit for expanding the tubular film. Therefore, the melt conductor according to the present invention is particularly used as a melt distributor for distributing the polymer melt.
[0127] In a fourth aspect of the present invention, this problem is solved by a method for operating an extrusion installation according to the above-mentioned embodiment, wherein the extrusion installation is fed with at least one extrudable polymer, in particular at least one plastic, which is plasticized to form a respective polymer melt, and the polymer melt is fed to a molten conductor of the above-mentioned type, which distributes and / or mixes the polymer melt.
[0128] The extrudable polymer is fed, for example, through a silo or conveying unit that is either part of the extrusion equipment or a separate component or assembly. The extrudable polymer can be fed to the extrusion equipment as granules, i.e., in a substantially solid form, or as an at least partially molten melt.
[0129] After being delivered to the extrusion equipment, the granules may be processed by a feed unit, particularly an extruder, melted and / or plasticized through additional processing steps, and delivered to a melt conductor as a polymer melt for bonding and / or separation. After separation and / or bonding, the polymer melt may be delivered from the melt conductor to an extrusion nozzle, which further processes the polymer melt to obtain an extruded product.
[0130] The advantage of such equipment is that it can be operated much more economically with such extrusion dies, since product changeover times for polymer changes are much shorter and the overall operating time of the extrusion die before die cleaning is substantially longer, thus optimizing cleaning times.
[0131] Within the framework of the present invention, all components of the extrusion equipment described as additively manufactured components, particularly the extrusion die, molten conductors, and molten conductor blocks, are formed from materials suitable for additive manufacturing and / or casting. Particularly suitable materials are metals, plastics, and / or ceramics. By "plastics," we mean high-performance plastics that allow extrusion die operating temperatures above 200°C. The advantage of additively manufactured components from ceramics, particularly melt channels, is that deposits are minimized. Advantageously, the surfaces of the melt channels that come into direct contact with the polymer melt are formed as single- or multi-layer ceramic sheets in the form of inliners from a material different from the already available melt conductor blocks. In other words, portions of the channels of each multi-channel system can have single- or multi-layer ceramic sheets for channel surface modification. However, it is also conceivable to form the entire melt conductor block partially or entirely from ceramic. In other words, different segments of the melt conductor block, including the multi-channel system, can be made of different materials, which can be advantageously utilized for the respective application. These can be, in particular, different metals or a combination of metal, ceramic, and / or plastic.
[0132] Depending on the material of the fused conductor block and / or the channels of the multi-channel system, surface treatments can be performed to finish the surfaces of the channels of the multi-channel system. This can include heat treatments, chemical vapor deposition, physical vapor deposition, infiltration, etc. In this way, one or more layers of coatings can be formed, particularly on the surfaces of the channels of the multi-channel system, which influence the condition of the surfaces of the channels, thereby advantageously improving the flow characteristics of the polymer melt and reducing deposits in the multi-channel system.
[0133] After fabrication of the fused conductor block, the interior surfaces of the channels of the multi-channel system and the channel coating, if present, can be subjected to a finishing treatment. This can include cleaning and / or rinsing the multi-channel system. Grinding of the channel flow is also possible. These steps can also be performed between maintenance intervals or in the event of a product changeover to dislodge and remove any deposits within the multi-channel system.
[0134] Naturally, the features of the solutions described above or claimed can also be combined, if desired, in order to cumulatively achieve the advantages and effects achievable in this case.
[0135] Other features, effects and advantages of the present invention are illustrated by the figures and the following specification in which examples of continuous polymer processing extrusion equipment and different molten conductor embodiments are presented and explained by way of example.
[0136] Components having at least substantially the same functionality may be designated by the same reference numeral in the individual figures, although a component may not necessarily be referenced and described in every figure. [Brief explanation of the drawings]
[0137] [Figure 1] 1 is a schematic diagram of a possible configuration of an extrusion installation having a molten conductor block and a molten conductor including a multi-channel system according to a first alternative embodiment. [Figure 2] (A) A schematic perspective view of the multi-channel system according to Figure 1, in which the melt conductor is embodied as a melt distributor. (B) A schematic cross-sectional view of two melt channels downstream in the designated direction of polymer melt flow. [Figure 3] 1 is a schematic perspective view of a second alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten mixer. [Figure 4]10 is a schematic perspective view of a third alternative embodiment of a multi-channel system, in which the conductor is embodied partially as a melt distributor and partially as a melt mixer. [Figure 5] 10 is a schematic perspective view of a fourth alternative embodiment of a multi-channel system, in which the molten conductor is embodied partially as a molten mixer and partially as a molten distributor. [Figure 6] 6A and 6B are schematic perspective views of a fifth alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor, respectively. [Figure 7] (A) A schematic top view of a sixth alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor. (B) A schematic perspective view of the sixth alternative embodiment according to Fig. 7(A). (C) Another schematic perspective view of the sixth alternative embodiment according to Figs. 7(A) to 7(C). [Figure 8] 10 is a schematic top view of a seventh alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor. [Figure 9] FIG. 13 is a schematic perspective view of an exemplary branching structure of an eighth alternative embodiment of a multi-channel system. [Figure 10] FIG. 13 is a schematic perspective view of an exemplary branching structure of a ninth alternative embodiment of a multi-channel system. [Figure 11] 13 is a schematic perspective view of a tenth alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor. [Figure 12] 11 is a schematic perspective view of an eleventh alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor. [Figure 13](A) A schematic perspective view of a twelfth alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor. (B) A schematic top view of the twelfth alternative embodiment according to FIG. 13(A). (C) Another schematic perspective view of the twelfth alternative embodiment according to FIGS. 13(A) and 13(B). (D) Another schematic perspective view of the twelfth alternative embodiment according to FIGS. 13(A) to 13(C). [Figure 14] (A) A schematic perspective view of a thirteenth alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor. (B) A schematic top view of the thirteenth alternative embodiment according to Figure 14(A). (C) Another schematic perspective view of the thirteenth alternative embodiment according to Figures 14(A) and 14(B). [Figure 15] 15(A) is a schematic perspective view of a fourteenth alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor; and (B) is a schematic top view of the fourteenth alternative embodiment according to FIG. 15(A). [Figure 16] 16(A) is a schematic diagram of a fifteenth alternative embodiment of a multi-channel system, in which the molten conductor is embodied as a molten distributor; and (B) is a schematic side view of the fifteenth alternative embodiment according to FIG. 16(A). DETAILED DESCRIPTION OF THE INVENTION
[0138] FIG. 1 is a highly simplified diagram of an extrusion installation 3. The extrusion installation 3 comprises a feed unit 23, which is adapted to feed and process a polymer melt 24, in this case a plastic material. The feed unit 23 is currently an extruder (not shown in detail here) that plasticizes at least one extrudable polymer 29 to form the polymer melt 24. The feed unit 23 can also be adapted to feed one or more different polymer melts 24 having the same or different properties. The polymer melt 24 is continuously fed by the feed unit 23 into an extrusion die 2, which comprises a melt conductor 1 and an extrusion nozzle 14 downstream in a designated flow direction 25 of the polymer melt 24. The extrusion die 2 is integrated into a continuously operating extrusion installation 3, in which the polymer melt 24 is continuously conveyed through the melt conductor 1 in a general machine direction 18; the terms "downstream" and "upstream" refer to this general machine direction 18.
[0139] The molten conductor 1 adapted as a molten distributor in this first example of embodiment has a molten conductor block 4 with a multi-channel system 5 extending three-dimensionally inside the molten conductor block 4. The molten conductor block 4 is manufactured by additive manufacturing and can be integrated into the extrusion equipment 3 operating continuously as a replaceable component of the molten conductor 1. The multi-channel system 5 according to the first embodiment is shown in detail in FIG. 2(A).
[0140] The supply unit 23 is flanged onto the input side 26 of the molten conductor block 4, and the extrusion nozzle 14 is formed on the output side 27 of the molten conductor block 4, so that the extrusion nozzle 14 is also manufactured additively, i.e., together with the molten conductor block 4. The output side 27 of the molten conductor block 4 is formed with a collection chamber 15 into which the multi-channel system 5 opens. The collection chamber 15 is adapted to receive the polymer melt 24 distributed by the molten conductor 1, embodied as a melt distributor, and continuously deliver it to the extrusion nozzle 14. As can be seen in FIGS. 2A-16B, the multi-channel system 5 has an output section 7 adapted to direct the polymer melt 24 into the collection chamber 15 for delivery to the extrusion nozzle 14. The extrusion nozzle 14 shown in FIG. 1 has an extrusion nozzle output section 22 with a width B of more than 5,000 mm. The width B defines the width of the extrusion product 30 produced by the extrusion system, which is embodied as a film in FIG. 1.
[0141] During additive manufacturing of the fused conductor block 4, a hollow chamber system 16 is formed having a plurality of honeycomb-shaped hollow chambers 17, which hollow chamber system 16 forms the fused conductor block 4. The hollow chamber system 16 is proposed here only to extend substantially through the entire fused conductor block 4. The hollow chamber system 16 houses the multi-channel system 5, which is also manufactured by additive manufacturing. The multi-channel system 5 is therefore supported by the hollow chamber system 16, which is spatially arranged around the multi-channel system 5.
[0142] The molten conductor 1 distributes the polymer melt 24 (FIG. 2A) in the multi-channel system 5, in relation to its designated flow direction 25, from an input 6 located on the input side 26 of the molten conductor block 4, which in this case is embodied as a melt distributor block, via several serially arranged branches 8, several levels 9a, 9b of sub-branches 10, and several intervening levels of separated melt channels 11, to multiple outputs 7 fluidly connected to the input 6 and located on the output side 27 of the molten conductor block 4. Thus, the multi-channel system 5 has one input 6 and multiple outputs 7 fluidly connected to the input 6. The input 6 on the input side 26 of the molten conductor block 4 is consequently formed as an input opening through which the polymer melt 24 is fed into the multi-channel system 5 of the molten conductor block 4.
[0143] For simplicity, the multichannel system 5 in FIG. 2A is shown with only one branch 8 and two levels of sub-branches 10 (9a, 9b). The other sub-branches 10 and melt channels are formed in a substantially similar manner to distribute the polymer melt 24 across the respective widths B of the extrusion nozzle output 22. Thus, three or more levels of sub-branches 10 are possible. In a designated flow direction 25 of the polymer melt 24, the melt channel 11a in the a-th level 12a is disposed between the input 6 and the branch 8, the sub-branch 10 of the melt channel 11b in the b-th level 12b is disposed between the branch 8 and the first level 9a, and the sub-branch 10 of the melt channel 11c in the c-th level 12c is disposed between the sub-branch 10 of the first level 9a and the sub-branch 10 of the second level 9b. The secondary branch 10 of the second level 9b is followed by a melt channel 11d of the dth level 12d. FIG. 2(A) also shows that the number of melt channels 11 increases with each level. That is, one melt channel 11a of the ath level splits into two melt channels 11b of the bth level. The two melt channels 11b of the bth level then split into two melt channels 11c of the cth level, respectively. That is, a total of four melt channels 11c are formed, and so on. In other words, the number of melt channels 11 doubles from one level to the next in the flow direction 25. Thus, the multichannel system 5 and its individual cavities in the form of melt channels 11, branches 8, and secondary branches 10 are also manufactured by additive manufacturing. Furthermore, additional cavities can be provided in the form of collection chambers 15, local expansions 28, or junctions 13, which will be described in more detail in the further description of alternative embodiments. The cavity may also be embodied as a distribution or mixing chamber (not shown here) or the like.
[0144] In this embodiment, the melt channels 11a in the a-th level 12a have first local cross sections that are smaller than second local cross sections of the divided melt channels 11b in the b-th level 12b, e.g., all local cross sections of the divided melt channels 11b in the b-th level 12b are also larger than the local cross sections of the divided melt channels 11c in the c-th level 12c.
[0145] The relationship between the local cross-sectional area of a melt channel 11 at one level and the melt channel 11 at the level immediately upstream or downstream thereof can be determined by the circumference and cross-sectional area of each melt channel, particularly for melt channels 11 of simple structure. This is illustrated in Figure 2(B), where the circumference U2 and cross-sectional area A2 of at least two melt channels 11b that derive from and separate from one common melt channel 11a are Dimensioned according to TIFF0007737365000002.tif19170, where U1 is the first circumference, A1 is the first cross-sectional area of the common melt channel 11a, U2 is the second circumference, A2 is the second cross-sectional area of one of the divided melt channels 11b, and n K is the total number of divided melt channels 11b, x is greater than or equal to -0.5, preferably a value of at least 0.5, preferably a value of at least 0.75, and x is a value of at most 4, preferably a value of at most 2.5, more preferably a value of at most 1.5.
[0146] In the case of a shape of the cross section of the melt channel in which the narrowest and widest points are close to each other in the local cross section of each melt channel, on the other hand, the number of divided melt channels n K Depending on the cross-section, it may be advantageous to establish only a relationship between the first cross-sectional area A1 of the divided melt channel 11 a and the second cross-sectional area A2 of the divided melt channel 11 b. In the case of a circular cross-section, for example, the narrowest and widest positions of the local cross-sections of each melt channel 11 a, 11 b are identical and correspond to the diameter.
[0147] Therefore, the cross section A2 of at least two melt channels 11b that originate from and are divided by the common melt channel 11a is A2=A1*(1 / n K ) 2 / y It is possible to determine the dimensions according to the where A1 is the first cross-sectional area of the common melt channel 11a, A2 is the second cross-sectional area of one of the divided melt channels 11b, and n K is the total number of divided melt channels 11b, y has a value of 2, preferably at least 2.5, and more preferably at least 2.85, and y has a maximum value of 7, preferably at most 5, and more preferably at most 3.35. This is particularly advantageous when the melt channels 11 of the multi-channel system 5 have local cross-sectional shapes that deviate from a circular cross-section over at least half the length of each melt channel 11, preferably at least two-thirds the length of each melt channel 11, and preferably at least three-quarters the length of each melt channel 11. This geometric relationship between the melt channels 11 can be applied to all of the above-mentioned embodiments.
[0148] Here, melt channels 11a in the a-th level 12a are oriented toward the input 6 in a designated flow direction 25 of the polymer melt 24, and melt channels 11b in the b-th level 12b are oriented toward the output 7 relative to melt channels 11a in the a-th level 12a. Melt channels 11c in the c-th level 12c are oriented toward the input 6 relative to melt channels 11d in the d-th level 12d, and melt channels 11d in the d-th level are oriented toward the respective output 7 relative to melt channels 11 in the a-th level 12a, the b-th level 12b, and the c-th level 12c. In this manner, the melt conductor 1 functions as a melt distributor.
[0149] In FIG. 3 , in a second alternative multi-channel system 5 of a second alternative molten conductor block 4 (not shown here), the molten conductor 1 is arranged in the extrusion die 2 and extrusion equipment 3 in a reverse order, in contrast to FIG. 2(A) , and is therefore embodied as a melt mixer in this alternative embodiment. This is due to the fact that the molten conductor 1 has multiple inputs 6 (eight in this case) on the input side 26 of the molten conductor block 4, through which one or up to eight identical or at least partially different polymer melts 24 are fluidly connected to the inputs 6 and combined with outputs 7 arranged on the output side 27 of the molten conductor block 4. In this case, the molten conductor block 4 is not shown, but only the multi-channel system 5 is shown for clarity. The multi-channel system 5 is formed substantially identically to the embodiment of FIGS. 1 and 2(A) . The only difference is that the polymer melts 24 are not distributed through the multi-channel system 5, but up to eight different polymer melts 24 can be combined by the multi-channel system 5. The multi-channel system 5 now also has several branches 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, 11d arranged between them, but against the specified flow direction 25 of the polymer melt 24, i.e. from the output side 27 to the input side 26.
[0150] Opposite to the designated flow direction 25 of the polymer melt 24, the melt channels 11a of the a-th level 12a are arranged between the respective output sections 7 and the branches 8, between the branches 8 and the sub-branches 10 of the first level 9a and the melt channels 11b of the b-th level 12b, and between the sub-branches 10 of the first level 9a and the sub-branches 10 of the second level 9b and the melt channels 11c of the c-th level 12c. The melt channels 11d of the d-th level 12d are also arranged downstream of the sub-branches 10 of the second level 9b, which is the level fluidly connected to the input section 6. Thus, in the designated flow direction 25 of the polymer melt 24, the number of melt channels 11 decreases at each level from the input section 6 to the output section 7. That is, two of the eight melt channels 11d currently on the dth level 12d are coupled to one melt channel 11c on the cth level 12c, i.e., four melt channels 11c in the cth level 12c in total. Two of the four melt channels 11c on the cth level 12c are also coupled to one melt channel 11b on the bth level 12b, i.e., there are two melt channels 11b on the bth level 12b in total, from which the two melt channels 11b on the bth level 12b form the melt channel 11a on the ath level that is directly fluidly connected to the output 7.
[0151] 1 and 2(A), the local cross section of each melt channel level increases with each lower level in the designated flow direction 25 of the polymer melt 24. The melt channel 11a in the a-th level 12a is oriented toward the output 7 in the designated flow direction 25 of the polymer melt 24, and the melt channel 11b in the b-th level 12b is oriented toward the input 6 relative to the melt channel 11a in the a-th level 12a. The melt channel 11c in the c-th level 12c is oriented toward the output 7 relative to the melt channel 11d in the d-th level 12d, and the melt channel 11d in the d-th level 12d is oriented toward the input 6 relative to the melt channels 11a, 11b, and 11c in the a-th level 12a, the b-th level 12b, and the c-th level 12c. This allows the molten conductor 1 to function as a melt mixer.
[0152] FIG. 4 illustrates a third alternative multi-channel system for a third alternative fused conductor block 4 (not shown). This multi-channel system 5 is formed as a combination of fused conductors 1 formed in part as melt distributors and in part as melt mixers. The input side of the fused conductor block 4 is first provided with an input section 6 that enters the multi-channel system 5. The melt channel 11a on the a-th level 12a is separated into multiple melt channels 11d on the d-th level 12d, similar to the embodiment of FIG. 2(A). Further downstream in the designated direction of polymer melt flow 25, starting from the melt channel 11d on the d-th level 12d, the melt channels 11c and 11b on the c'-th level 12c' and the b'-th level 12b' are recombined to the melt channels on the a-th level 12a' or to the output section 7, respectively, in a manner similar to the embodiment of FIG. 3.
[0153] 5 shows a fourth alternative multi-channel system 5 in a fourth alternative molten conductor block 4 (not shown), and the combination of molten conductors 1 formed partially as a melt mixer and partially as a melt distributor is also shown here. However, the method of functioning is opposite to that shown in the embodiment of FIG. 4. The molten conductor block 4 has, on its input side 26, several inputs 6 to the multi-channel system 5, and melt channels 11d of the dth level 12d, which are fluidly connected directly to the inputs 6, are combined from one level to another, up to the melt channels 11a of the ath level 12a, along a designated flow direction 25 of the polymer melt 24, similar to the example embodiment of FIG. 3. Further downstream, this melt channel 11a of the a-th level 12a is divided from one level to another via branches 8 into sub-branches 10 of several levels 9a', 9b', as well as melt channels 11b, 11c, 11d of intervening levels 12b', 12c', 12d', in a manner similar to the embodiment of Figures 2(A) and 2(B), until a plurality of output sections 7 are arranged on the output side 27 of the molten conductor block 4.
[0154] The multi-channel systems 5 according to the embodiments of FIGS. 4 and 5 are not limited to the shapes and arrangements described herein. It is also possible to provide additional sections upstream and / or downstream of each multi-channel system 5, configured as melt distributors and / or melt mixers, which can be implemented and combined as needed. However, it is advantageous if the polymer melt 24 always has the same melt history at the output section 7, regardless of which melt channel 11 or melt channel sequence it flows through. Thus, in the case of eight melt channels 11d on the dth level 12d, the polymer melt 24 is divided into a maximum of eight different melt streams. In this context, the "same history" of the polymer melt 24 means that all melt streams of the polymer melt 24 have traveled the same path through the multi-channel system 5 and have flowed through the same number of melt channels 11, branches 8, and sub-branches 10 when they reach the output section 7.
[0155] The embodiments described below according to Figures 6(A) to 16(B) refer only to the molten conductor 1 configured as a melt distributor, in which the polymer melt 24 of the multi-channel system 5 is distributed from each input 6 to multiple outputs 7. The arrangement and numbering of the melt channel 11 levels and the branch 8 and sub-branch 10 levels are therefore similar to the first embodiment shown in Figures 1 and 2(A). Naturally, the following embodiments are also suitable for implementing the molten conductor 1 as a melt mixer or any combination of melt mixer and melt distributor.
[0156] 1 to 5, the multi-channel system 5 is formed in each case to lie substantially in one plane, with the respective inputs 6 and outputs 7 as well as all melt channels 11, branches 8 and sub-branches 10 consequently being arranged in one common plane. Thus, at least three degrees of freedom are used to form the multi-channel system 5.
[0157] In contrast, a fifth alternative multi-channel system 5 of a fifth alternative fused conductor block 4, not shown here, is shown in Figures 6(A) and 6(B), in which the multi-channel system 5 branches three-dimensionally in space using five degrees of freedom. As clearly shown in Figure 6(B), the melt channels 11 start from the input 6 and extend in the direction of the flow of the polymer melt 24, being distributed over several levels at least partially downward, to the left, to the right, into and out of the leaf level. Thus, melt channel 11, fluidly connected to input 6, branches over branch 8 and sub-branch 10 to output 7, which in this configuration is distributed into two substantially parallel planes, with sub-branch 10 on first level 9a being formed such that melt channel 11c on c-th level 12b extends at a substantially 90° rotation relative to melt channel 11b on b-th level, and starting from each melt channel 11c on c-th level, separate distribution systems 29a-29d are formed. The first and second distribution systems 29a, 29b are arranged in one plane, and the third and fourth distribution systems 29c, 29d are arranged in a second plane, with the two planes being substantially parallel.
[0158] Such a molten conductor 1 makes it possible in an easy manner to distribute the polymer melt 24 not only uniformly in width in a manner similar to that shown in Figure 2(A) but also uniformly in height or depth in the transverse direction, i.e., depending on the direction of view, so that the polymer melt 24 can emerge from the molten conductor block 4 over a relatively large surface. This is particularly suitable for producing filaments or endless filaments, in particular for producing spunbond fabrics by means of a multi-row nozzle die.
[0159] Regardless of the arrangement of the branches 8 and sub-branches 10 relative to the melt channel 11 and their arrangement in three-dimensional space, the local cross section of the melt channel 11 decreases from one level to the next up to the output section 7, the melt channels 11 of each level 12a-12e are always formed symmetrically in all distribution systems 29a-29d, and the separated melt streams of the polymer melt 24 have the same melt history.
[0160] Thus, the outputs 7 of the first and second distribution systems 29 a, 29 b or the outputs 7 of the first plane are located in a theoretically straight first line, and the outputs 7 of the third and fourth distribution systems 29 c, 29 d or the outputs 7 of the second plane are located in a theoretically straight second line. Both lines and planes are arranged parallel to each other. Because all melt channels 11 are connected to a single input 6, all melt streams have the same material properties at their respective outputs 7 by carrying the same polymer melt 24.
[0161] 7(A)-7(D) show a sixth alternative multi-channel system 5 of a sixth alternative fused conductor block 4 (not shown here), where the multi-channel system 5 is spatially divided three-dimensionally using six degrees of freedom. In this embodiment, two melt channels 11b of the b-th level 12b are shown to extend partially opposite a global machine direction 18. The global machine direction 18 runs from the input 6 to the output 7 of a designated melt stream of polymer melt 24. All melt channels 11b of the b-th level 12b have a local machine direction 19 that can always have the same or varying orientation in the longitudinal direction of the melt channel 11, depending on the embodiment and the extension of each melt channel 11. It can be advantageous if the local machine direction 19 extends at least partially opposite the global machine direction 18. This is particularly shown in FIG. 7(A).
[0162] In this case, the input section 6 and output section 7 of the multi-channel system 5 are arranged substantially in a first plane, and the melt channels 11b of the b-th level 12b extend partially transversely to this first plane, so that the secondary branches 10 of the first level 9a are arranged in a second plane parallel to the first plane. The attached melt channels 11c of the c-th level 12c extend partially in the second plane and are returned to the first plane for further distribution of the polymer melt 24. By directing the melt channels 11 three-dimensionally in space, and in particular by directing the local machine direction 19 of the melt channels 11 partially against the global machine direction 18, the polymer melt 24 is distributed over a smaller axial build space, i.e., in the global machine direction 18 of the molten conductor 1. In this way, the molten conductor 1 can be constructed more compactly.
[0163] FIG. 8 shows a seventh alternative fused conductor block 4 of the fused conductor 1 having a seventh alternative multi-channel system 5, where the three-dimensionally extending multi-channel system 5 is embodied in a manner similar to the multi-channel system 5 of FIG. 7 in terms of the arrangement, structuring, and guidance of the melt channels 11. Shown is a possible arrangement of the multi-channel system 5 of the fused conductor block 4, shown here only diagrammatically as a rectangular parallelepiped, where the three-dimensional guidance of the melt channels 11 in space allows the fused conductor block 4 to be configured with a relatively large width in the global machine direction 18 and at the same time a low structural height and axial length. Using such a fused conductor block 4, it is possible to distribute the polymer melt 24 so as to produce nonwoven fabrics, particularly those having 20 to 10,000 individual filaments per meter of width.
[0164] FIG. 9 illustrates an exemplary embodiment of a branch 8 or sub-branch 10 of a multi-channel system 5 in an eighth alternative embodiment of the eighth alternative multi-channel system 5. In the case of a molten conductor 1 embodied at least partially as a melt distributor, the melt channel 11a on the a-th level 12a can be split into three melt channels 11b on the b-th level 12b via the branch 8. The three melt channels 11b on the b-th level 12b are arranged evenly around the melt channel 11a on the a-th level 12a. Irregular arrangements around the melt channel 11a on the a-th level 12a are also possible. Conversely, in a molten conductor 1 formed at least partially as a melt mixer, the three melt channels 11b can be combined into one melt channel 11a.
[0165] FIG. 10 illustrates an exemplary embodiment of a branch 8 or sub-branch 10 of a multi-channel system 5 in a ninth alternative embodiment of the multi-channel system 5. With a melt conductor 1 at least partially embodied as a melt distributor, the melt channel 11a on the a-th level 12a can be split into four melt channels 11b on the b-th level 12b via the branch 8. The four melt channels 11b on the b-th level 12b are evenly distributed and arranged around the melt channel 11a on the a-th level 12a. Again, irregular arrangements around the melt channel 11a on the a-th level 12a are also contemplated. Conversely, with a melt conductor 1 at least partially embodied as a melt mixer 1, the four melt channels 11b can be combined into a common melt channel 11a.
[0166] FIG. 11 illustrates an example of a tenth embodiment with a tenth alternative multi-channel system 5. The multi-channel system 5 is substantially the same as the multi-channel system 5 of FIG. 1. The main difference is that here, each melt distributor block 4 in the region of a melt channel 11c of the c-th level 12c has a static functional element 21 in the form of a static mixing element for influencing a designated polymer melt 24. Each functional element 21 is located within a localized area 28 of the melt channel 11c of the c-th level 12c and performs mixing of the polymer melt 24 guided and distributed inside the melt channel 11c of the c-th level 12c. In this way, uniform distribution of the melt strands of the polymer melt 24 guided within each melt channel 11c, particularly their flow and material properties, can be ensured. Therefore, each functional element 21 is located in one of the melt channels 11c of the c-th level 12c between the secondary branches 10 of the first level 9a and the secondary branches 10 of the second level 9b. The cross-sectional dimensions and shapes of each melt channel 11c of the c-th level 12c are substantially equal before and after the local expansion 28. Alternatively, static mixing elements can be placed directly in each melt channel 11c rather than in the local expansion.
[0167] FIG. 12 shows an example of an eleventh embodiment with an eleventh alternative multi-channel system 5. The multi-channel system 5 is the same as the multi-channel system 5 of FIGS. 6A and 6B. Furthermore, the melt conductor block 4 has a media channel 20 extending spatially between the melt channels 11 of the multi-channel system 5, here between two levels of distribution systems 29a, 29b, 29c, and 29d, to implement fluid guidance. The fluid guidance is used to control the temperature of the melt conductor block 4 and, therefore, the polymer melt 24 guided within the multi-channel system 5. The media channel 20 is not fluidly connected to the melt channels 11 of the multi-channel system 5 and implements temperature control of the molten conductor 1, particularly the melt conductor blocks 4a-4e, during operation of the extrusion equipment 3. Furthermore, any number of additional media channels of any configuration may be provided, arranged fluidically separated from the melt channels 11 of the multi-channel system 5 of the melt distributor block 4. The additional medium channel may also be embodied as a drying shaft adapted to accommodate, for example, electrical wires and / or a measuring unit.
[0168] In the example embodiments of Figures 13(A) to 15(B) below, the fused conductor block 4 has a first multi-channel system 5a and a second multi-channel system 5b that are fluidly separated, although three or more multi-channel systems are also possible without any problems.
[0169] 13(A)-13(D) illustrate a twelfth alternative embodiment in which two multichannel systems 5a, 5b are fluidly separated from each other. In other words, a first polymer melt 24 is introduced into a first input 6a of the first multichannel system 5a, and a second polymer melt 24 is introduced into a second input 6b of the second multichannel system 5b. The two polymer melts 24 can have the same or different properties. Each multichannel system 5a, 5b has a respective input 6a, 6b for delivering the respective polymer melt 24 and multiple outputs 7a, 7b for delivering the polymer melt 24 to an extrusion nozzle (not shown here). The first multichannel system 5a is embodied in a manner substantially similar to the multichannel system 5 of FIG. 2(A). Therefore, for the sake of brevity, identical reference numerals will not be repeated and reference will be made to the respective descriptions.
[0170] Starting from the input 6a of the second multichannel system 5b, the melt channels 11a of the a-th level 12a of the second multichannel system 5b initially extend parallel to the melt channels 11a of the a-th level 12a of the first multichannel system 5a. However, following the bifurcation 8, the melt channels 11b of the b-th level 12b are rotated 45° relative to the first multichannel system 5a so that the melt channels 11a of the b-th level 12b, the c-th level 12c, and the d-th level 12d of the second multichannel system 5b extend toward the first multichannel system 5a, successively approaching the melt channels 11 of the first multichannel system 5a with each level increase. This brings the output 7b of the second multi-channel system 5b into relatively close proximity to the output 7a of the first multi-channel system 5a, and the melt stream of polymer melt distributed by the second multi-channel system 5b emerges in the region of the outputs 7a, 7b at a relatively short distance from the melt stream of polymer melt 24 distributed by the first multi-channel system 5a.
[0171] In the front view of FIG. 13A, the output section 7a of the first multi-channel system 5a and the output section 7b of the second multi-channel system 5b are arranged in series and spaced apart from each other. Furthermore, the first output section 7a of the first multi-channel system 5a is arranged in a first straight line, and the second output section 7b of the second multi-channel system 5b is arranged in a second straight line, with these straight lines being substantially parallel. In other words, the output sections 7a and 7b of each multi-channel system 5a and 5b are arranged in two planes that are parallel to each other. In this manner, a two-layer film web can be produced, in which the layers can have the same or different material properties.
[0172] The thirteenth alternative embodiment according to Figures 14(A) to 14(C) shows a thirteenth alternative embodiment identical to the previously described embodiment according to Figures 13(A) to 13(D). The main difference is simply that the outputs 7a, 7b of the multi-channel systems 5a, 5b are not arranged one behind the other, but are offset relative to one another transversely to the designated flow direction 25 or global machine direction 18 of the respective polymer melt 24.
[0173] This can be seen particularly well in Figure 14(C). Each output 7a of the first multi-channel system 5a is located between two outputs 7b of the second multi-channel system 5b. The two multi-channel systems 5a, 5b are spatially offset from each other. This allows the outputs 7a, 7b of the multi-channel systems 5a, 5b to be much closer to each other than in the embodiments of Figures 13(A) to 13(D).
[0174] Figures 15(A) and 15(B) show a fourteenth alternative embodiment in which two multichannel systems 5a, 5b are fluidly separated from one another. A first polymer melt 24 is fed to a first input 6a of the first multichannel system 5a, and a second polymer melt 24 is fed to a second input 6b of the second multichannel system 5b. The polymer melts can have the same or different properties. Thus, each multichannel system 5a, 5b has a respective input 6a, 6b for feeding the respective polymer melt 24 and multiple outputs 7a, 7b for feeding the respective polymer melt 24 to the extrusion nozzle 14. The first multichannel system 5a is formed in a manner substantially similar to the multichannel system 5 of Figures 6(A) and 6(B), with the melt channel 11b of the b-th level 12b branching into separate distribution systems 29a, 29b, 29c, and 29d. Therefore, for the arrangement of the melt channels 11 of the first multi-channel system 5a, reference is made to the description of Figures 6(A) and 6(B), and for the sake of simplicity, the repetition of identical reference numerals is omitted unless absolutely necessary.
[0175] The second multi-channel system 5b is formed substantially identically to the embodiment of Figure 2(A). The only difference is that the melt channel 11a on the a-th level 12a of the second multi-channel system 5b is offset relative to the melt channels 11c and 11d on the c-th and d-th levels 12c and 12d of the second multi-channel system 5b. Here, the first multi-channel system 5a has melt channels 11a-11e on five levels 12a-12e (similar to Figures 6(A) and 6(B)), while the second multi-channel system 5b has melt channels 11a-11d on four levels 12a-12d.
[0176] The first input 6a of the first multichannel system 5a is centrally disposed, and the second input 6b of the second multichannel system 5b is disposed parallel thereto, thus eccentrically distributing the fluids of the multichannel systems 5a and 5b. The melt channels 11a of the a-th level 12a of the first multichannel system 5a are parallel to the central axis M, and the melt channels 11c and 11d of the c-th and d-th levels 12c and 12d, as well as the output 7b of the second multichannel system 5b, are disposed along the central axis M and at the input 6a of the first multichannel system 5a. Thus, the melt channels 11b of the b-th level 12b of the second multichannel system 5b are shaped so that the polymer melt 24 is directed from the melt channels 11a of the a-th level 12a of the first multichannel system 5a toward the central axis M. In this way, it is achieved that the outputs 7a of the first and second distribution systems 29a, 29b and the third and fourth distribution systems 29c, 29d are arranged equidistant from the output 7b of the second multi-channel system 5b.
[0177] In other words, the first output section 7a of the first multi-channel system 5a is partially aligned in a first straight line and partially aligned in a second straight line, and the second output section 7b of the second multi-channel system 5b is aligned in a third straight line. The three lines are substantially parallel. In other words, the output sections 7a, 7b of each multi-channel system 5a, 5b are aligned in planes parallel to one another. In this way, a three-layer film web can be produced, with an outer layer having a first material property and an inner layer surrounded by an outer layer having a second material property. This can be advantageous for sustainably produced extrusion products, for example, if the polymer melt 24 distributed to the inner surface by the second multi-channel system 5b is made from recycled material, while the polymer melt 24 distributed across the two outer surfaces by the first multi-channel system 5a is made from virgin material. This conserves virgin material and simultaneously promotes the reuse of recycled material.
[0178] Figures 16(A) and 16(B) show a fifteenth embodiment in which two multi-channel systems 5a, 5b are similarly formed in a manner substantially similar to the embodiment of Figures 13(A)-13(D). The two multi-channel systems 5a, 5b are first fluidly separated, with the first polymer melt 24 being fed to the first input 6a of the first multi-channel system 5a and the second polymer melt 24 being fed to the second input 6b of the second multi-channel system 5a. The difference from the embodiment of Figures 13(A)-13(D) essentially lies in the fact that, rather than each of the multi-channel systems 5a, 5b having separate outputs 7a, 7b, the first multi-channel system 5a has a junction 13 with the second multi-channel system 5b, thereby providing a commonly used output 7 at the output side of the multi-channel systems 5a, 5b. Here, the polymer melts 24 of both multi-channel systems 5a, 5b are only briefly joined before exiting the fused conductor block 4. In this way, the properties of the two polymer melts 24 are largely maintained, and subsequent atomization simply results in the mutual adhesion of the polymer melts 24. The properties of the different polymer melts 24 can therefore be optimally adjusted depending on the requirements of the extruded product. Alternatively, it is possible to join the polymer melts 24 from the first and second multi-channel systems 5a, 5b earlier in order to achieve particularly good mixing of the polymer melts.
[0179] In this regard, it is expressly pointed out that the features of the solutions described above, in the claims or in the drawings can be combined, if desired, to achieve cumulative features, effects, and advantages. It is also expressly mentioned that the embodiments of Figures 1 to 10 can also be implemented with two or more multi-channel systems. For these, as well as for the other embodiments up to Figure 16(B), it can be said that the fused conductor block 4 can also be embodied with three multi-channel systems, four multi-channel systems, five or more multi-channel systems.
[0180] It should be understood that the above-described embodiments are only the first embodiment of the present invention, particularly the molten conductor, extrusion die, and extrusion equipment according to the present invention. Therefore, the implementation of the present invention is not limited to these embodiments. All features disclosed in this application are claimed to be essential to the present invention insofar as they are novel individually or in combination with respect to the state of the art.
[0181] The embodiments shown herein are merely examples of the present invention and therefore should not be understood as limiting. Alternative embodiments considered by those skilled in the art are equally included in the protection scope of the present invention. [Explanation of symbols]
[0182] 1. Fused conductor 2. Extrusion die 3 Extrusion equipment 4 Fused Conductor Block 5 Multi-Channel Systems 5a First multi-channel system 5b Second Multi-Channel System 6 Multi-channel system input section 6a Input section of first multi-channel system 6b Input section of second multi-channel system 7 Multi-channel system output section 7a Output section of first multi-channel system 7b Output section of second multi-channel system 8 Branches 9a First level branch 9b Second level branching 9c Third Level Branch 10 Sub-branch 11 Melt Channel 11a First level divided melt channel 11b Second level divided melt channel 11c Third level divided melt channel 11d Fourth level divided melt channel 11e Fifth level split melt channel 12a a-level melt channel 12a' a' level melt channel 12b b-level melt channel 12b' Level b' melt channel 12c C-level melt channel 12c' c' level melt channel 12d d-level melt channel 12d' d' level melt channel 12e e-level melt channel 13 Joint 14 Extrusion nozzle 15 Collection Chamber 16 Hollow Chamber System 17 Hollow chamber 18 Global machine direction 19 Local Machine Direction 20 Media Channels 21 Static functional elements 22 Extrusion nozzle output section 23 Supply Unit 24 Polymer Melt 25 Flow direction of polymer melt 26 Input side of fused conductor block 27 Output side of fused conductor block 28 Local expansion of the melt channel 29 Polymers 30 Extrusion Products A1 first cross-sectional area of the divided melt channel A2 second cross-sectional area of the divided melt channel B Width of extrusion nozzle output n k Total number of divided melt channels U1 First circumference of the divided melt channel U2 Second circumference of the divided melt channel M center axis
Claims
1. A molten conductor (1) for an extrusion die (2) of an extrusion installation (3), comprising: A fused conductor block (4) with a multi-channel system (5), the multi-channel system (5) is arranged with a three-dimensional extension inside the fused conductor block (4) and has at least one input (6) and at least one output (7) for a polymer melt; Between an input (6) and an output (7) fluidly connected to said input (6), several branches (8) arranged in series and several levels (9a, 9b, 9c) of sub-branches (10) are formed over several levels (12, 12b) of divided melt channels (11a, 11b), There are m melt channels (11a) of an a-th level (12a) having a local cross section of x-th and n melt channels (11b) of a b-th level (12b) having a local cross section of y-th, In this, if b>a, then n>m; the y local cross section of the melt channel (11b) at the b level (12b) is smaller than the x local cross section of the melt channel (11a) at the a level (12a); In a designated flow direction of the polymer melt, the melt channels (11 a) of the a-level (12 a) are oriented toward the input section (6) and the melt channels (11 b) of the b-level (12 b) are oriented toward the output section (7) so that the melt conductor (1) acts as a melt distributor of a designated melt stream of the polymer melt. or In the designated flow direction of the polymer melt, the melt channel (11 a) of the a-level (12 a) is oriented toward the output (7) and the melt channel (11 b) of the b-level (12 b) is oriented toward the input (6) so that the melt conductor (1) functions as a melt mixer for the designated melt stream of the polymer melt; The circumference (U) of at least two separate melt channels (11b) originating from a common melt channel (11a) 2 ) and cross-sectional area (A 2 )teeth, The dimensions are determined according to U 1 is the first circumference, and A 1 is the first cross-sectional area of the common melt channel (11a), and U 2 is the second circumference, and A 2 is a second cross-sectional area of one of the divided melt channels (11b), nK is the total number of divided melt channels (11b), and x is greater than or equal to -0.5, with x being a maximum value of 4.
2. A molten conductor (1) for an extrusion die (2) of an extrusion installation (3), comprising: A fused conductor block (4) with a multi-channel system (5), the multi-channel system (5) is arranged with a three-dimensional extension inside the fused conductor block (4) and has at least one input (6) and at least one output (7) for a polymer melt; Between an input (6) and an output (7) fluidly connected to said input (6), several branches (8) arranged in series and several levels (9a, 9b, 9c) of sub-branches (10) are formed over several levels (12, 12b) of divided melt channels (11a, 11b), There are m melt channels (11a) of an a-th level (12a) having a local cross section of x-th and n melt channels (11b) of a b-th level (12b) having a local cross section of y-th, In this, if b>a, then n>m; the y local cross section of the melt channel (11b) at the b level (12b) is smaller than the x local cross section of the melt channel (11a) at the a level (12a); In a designated flow direction of the polymer melt, the melt channels (11 a) of the a-level (12 a) are oriented toward the input section (6) and the melt channels (11 b) of the b-level (12 b) are oriented toward the output section (7) so that the melt conductor (1) acts as a melt distributor of a designated melt stream of the polymer melt. or In the designated flow direction of the polymer melt, the melt channel (11 a) of the a-level (12 a) is oriented toward the output (7) and the melt channel (11 b) of the b-level (12 b) is oriented toward the input (6) so that the melt conductor (1) functions as a melt mixer for the designated melt stream of the polymer melt; The cross section (A) of at least two melt channels (11b) originating from and dividing one common melt channel (11a) 2 )teeth, A 2 =A 1 *(1 / SK) 2/y The dimensions are determined according to A 1 is the first cross-sectional area of the common melt channel (11a), and A 2 is a second cross-sectional area of one of the divided melt channels (11b), nK is the total number of divided melt channels (11b), y is at least a value of 2, and y is a maximum value of 7.
3. The molten conductor (1) according to claim 1 or 2, characterized in that the melt channels (11) of the multi-channel system (5) have different local cross-sectional shapes that are at least partially different from a circular cross-sectional shape.
4. The fused conductor (1) according to any one of claims 1 to 3, characterized in that the fused conductor block (4) has a first multi-channel system (5a) and a second multi-channel system (5b).
5. 5. The molten conductor (1) according to claim 4, characterized in that the multi-channel systems (5a, 5b) are formed so as to be fluidly separated from one another, each multi-channel system (5a, 5b) having at least one input (6a, 6b) and at least one output (7a, 7b) for the polymer melt.
6. The fused conductor (1) according to claim 5, characterized in that the first multi-channel system (5a) has a junction (13) with at least the second multi-channel system (5b).
7. 7. The molten conductor (1) according to any one of claims 1 to 6, characterized in that each multi-channel system (5, 5a, 5b) is formed with a plurality of outputs (7a, 7b) adapted to direct the polymer melt into a collection chamber (15) for feeding to an extrusion nozzle (14).
8. The molten conductor (1) according to any one of claims 1 to 7, characterized in that the molten conductor (1) has a hollow chamber system (16) having at least one hollow chamber (17) spatially arranged between the melt channels (11) of the respective multi-channel systems (5, 5a, 5b).
9. 9. The molten conductor (1) according to claim 1, wherein the multi-channel system (5, 5a, 5b) has a global machine direction (18) through the molten conductor block (4) leading from the input (6, 6a) to the output (7, 7a) of a designated melt flow of the polymer melt, and wherein the melt channels (11) extend partially opposite to the global machine direction (18) when local machine directions (19) are projected onto the global machine direction.
10. The fused conductor (1) according to any one of claims 1 to 9, characterized in that the fused conductor block (4) has medium channels (20) for circulating fluid supply, for temperature control and / or for electrical wires and / or measuring units.
11. The fused conductor (1) according to any one of claims 1 to 10, characterized in that the fused conductor block (4) has a static functional element (21) for at least indirectly influencing the designated polymer melt.
12. The fused conductor (1) according to claim 11, characterized in that the static functional element (21) is a static mixing element.
13. 13. An extrusion die (2) for an extrusion installation (3) for producing extruded products, comprising a molten conductor (1) according to any one of claims 1 to 12, said molten conductor (1) being adapted to distribute and / or mix at least one specified polymer melt.
14. 14. Extrusion die (2) according to claim 13, characterized by an extrusion nozzle output (22) having a width (B) of more than 5,000 mm.
15. An extrusion installation (3) for producing extruded products, comprising an extrusion die (2) according to one of the preceding claims 13 or 14.
16. 16. A method of operating an extrusion installation (3) according to claim 15, wherein the extrusion installation (3) is fed with at least one extrudable polymer which is plasticized to form a respective polymer melt, and the respective polymer melt is fed to a molten conductor (1) according to any one of claims 1 to 12, which distributes and / or mixes the respective polymer melt.
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