Multi-row coaxial melt-blowing equipment

Abstract

The invention provides multi-row coaxial melt-blowing type equipment. The multi-row coaxial melt-blowing type equipment comprises a flow divider and a wire outlet device. And the flow divider is connected with the polymer fluid and the gas conveying pipeline through the primary inlet and the secondary inlet respectively. The yarn outlet device comprises a detachable spinning nozzle and a guide piece, the spinning nozzle is provided with a plurality of accelerating pipelines, a first hole, a second hole and a slit, and the spinning nozzle is used for distributing polymer filaments and allowing gas to pass through. The spinneret may also include an additional set or tip to flexibly adjust the filament output configuration. The guide part guides the filament through the air knife, and the conveying device is connected with the secondary inlet and the slit or the secondary outlet, so that effective distribution of the gas and the polymer fluid is ensured. The multi-row coaxial melt-blowing mold is compact in structure, convenient to maintain and adjust and suitable for producing high-quality non-woven fabrics.

Description

Technical Field

[0001] The object of the present invention is to provide an apparatus suitable for producing extruded polymer filaments for directly or indirectly manufacturing fabrics of the nonwoven type (also called NWF). Background Art

[0002] As we all know, nonwoven fabrics or NWFs are industrial products similar to fabrics, but the production process of nonwovens is different from weaving and knitting. Therefore, in nonwoven fabrics (NWFs), the fibers are randomly distributed and have no recognizable ordered structure; while in fabrics, the fibers have two main orthogonal directions, usually called weft and warp.

[0003] Currently, a wide variety of products containing nonwoven fabrics (NWFs) can be manufactured, depending on the manufacturing technology used, which is mainly related to the application of the product itself.

[0004] In particular, nonwoven fabrics (NWF) can be divided into high-quality nonwoven fabrics used for hygiene products and low-quality nonwoven fabrics mainly used for geotextiles.

[0005] From a technical point of view, non-woven fabrics can basically be divided into spunlace non-woven fabrics, spunbond non-woven fabrics and meltblown non-woven fabrics.

[0006] In the field of meltblowing technology, in particular, multi-row coaxial meltblowing equipment is already known. An example of such equipment is shown in FIG5- Figure 7 shown.

[0007] Generally, such equipment is used to draw polymer extruded from tubes arranged in a row, and the polymer interacts with a gas stream passing coaxially from the outside of the tubes, which pushes the fibers downward.

[0008] Specifically, the multi-row coaxial meltblown apparatus includes components defining coaxial holes that are arranged in rows and adapted to accommodate at least a portion of the tubes passing coaxially through the holes to allow diffusion of the polymer fluid while simultaneously allowing air or gas to diffuse from at least a portion of the holes.

[0009] Typically, these devices include devices called spin packs that provide a number of different components adapted to interact with each other. Typically, a spin pack consists of a spinneret and a diffusion device that includes one or more components called air plates.

[0010] Furthermore, the spinneret can also be connected to a cone and / or a breaker plate.

[0011] If a manifold is present, it is also connected to an extrusion head adapted to deliver at least the polymer fluid (and possibly pressurized air or gas) to the spin pack. The characteristics of the manifold and the cone are essentially the same as those used in spunbond and meltblown technologies.

[0012] However, a multi-row coaxial meltblowing apparatus including a spin pack does not include a diffusion device comprising a support structure adapted to support an air knife, does not include a tip structure, and does not have a simple spinneret adapted to specifically allow polymer extrusion.

[0013] In a multi-row coaxial meltblown machine, the spinneret is essentially a support for the tubes through which the polymer filaments are ejected. A diffuser is connected to the spinneret and includes an intermediate plate or air plate that allows the tubes to pass while allowing pressurized air or other gas to escape, and an outer guide or outer air plate, typically in a diverging shape, through which the polymer filaments are extruded downwardly under the pressure of air and then onto a conveyor belt in any machine used to manufacture nonwoven fabrics.

[0014] There are some obvious disadvantages of multi-row coaxial meltblown devices.

[0015] Specifically, to produce meltblown nonwovens, a tube must be threaded through a support, plate, and external guide. The tube must be aligned with the holes in the plate and guide to ensure proper operation. In practice, the ends of the tube extending through the holes in the external guide can also deform. These holes are designed to have a larger diameter than the tube to allow air or gas to escape. This possibility is primarily due to the need to maintain at least one slot between the plate and the external guide for distributing the gas or air.

[0016] Furthermore, the above devices have multiple overlapping plates, which makes them less compact and difficult to disassemble.

[0017] On the other hand, using multiple plates can present significant problems during installation, especially after multiple machining operations. It's essential to ensure that the plates and guides fit perfectly on all tubes. Furthermore, the outer plates and guides must be perfectly aligned to avoid unnecessary overlap, which could result in tube breakage or prevent the intermediate and outer air plates from being mounted on the inner air plates.

[0018] These problems are greatly magnified in multi-row, coaxial meltblown equipment due to the high processing temperatures and expansion that can occur in its individual components.

[0019] Furthermore, all of the above problems are further exacerbated when the spin pack is particularly large because the forces required to overcome the friction between the air plate and the tube when assembling or disassembling the air plate and the tube are greatly increased.

[0020] Furthermore, the prior art multi-row coaxial meltblown apparatuses generally employ a fixed configuration through which one or more rows of nonwoven fabric can essentially only be deposited starting from the same spinneret.

[0021] Therefore, if a second row of polymer filaments is to be deposited on the transfer roll, a second apparatus must be used, comprising at least an extrusion head, a diverter plate and a spin pack.

[0022] Of course, this demand has significant economic implications, primarily driven by the total cost of the equipment and the combined costs of management and maintenance. Summary of the Invention

[0023] In this case, the technical task of the present invention is to design a multi-row coaxial meltblown device, which can basically eliminate at least some of the above-mentioned shortcomings.

[0024] In this technical task, an important purpose of the present invention is to obtain a multi-row coaxial meltblown device that facilitates the assembly and disassembly of one or more components of the device.

[0025] Therefore, another important object of the present invention is to achieve an apparatus that is simple, quick, effective and economical to maintain.

[0026] Furthermore, another object of the present invention is to provide an extremely versatile device which makes it possible to easily vary the configuration of the tubes through which the polymer filaments are discharged, for example to adjust the density or the number of the tubes.

[0027] Furthermore, an important object of the present invention is to obtain a multi-row coaxial meltblown device that allows the production of multiple rows of polymer filaments.

[0028] Therefore, another important object of the present invention is to realize a kind of multi-row coaxial melt-blown type equipment, thereby can reduce the number of components required to realize the above-mentioned advantages.

[0029] In summary, another task of the present invention is to realize a multi-row coaxial meltblown device that can at least partially use components of traditional devices, thereby reducing the conversion costs of the device. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] The preferred embodiments of the present invention are described in detail below with reference to the accompanying drawings to illustrate the features and advantages of the present invention, in which:

[0031] Figure 1shows a cross-sectional view along a main plane of a multi-row coaxial meltblown apparatus according to a first embodiment of the present invention, in which the spinnerets comprise two groups and the flow splitter comprises a plurality of main inlets;

[0032] Figure 2 shows an exploded cross-sectional view along a principal plane of a multi-row coaxial meltblown apparatus according to a second embodiment of the present invention, wherein the diverter comprises a single main inlet;

[0033] Figure 3 shows a cross-sectional view along a principal plane of a multi-row coaxial meltblown apparatus according to a third embodiment of the present invention, in which the spinneret comprises a group and a tip;

[0034] Figure 4 Shown Figure 3 Exploded view of the equipment;

[0035] Figure 5a A main plan view showing the end of a branch of a conveyor of a multi-row coaxial meltblown apparatus according to the invention, in which conveyor only the primary and secondary ends of the same group are aligned;

[0036] Figure 5b A main plan view showing the end of a branch of a conveyor of a multi-row coaxial meltblown apparatus according to the invention, in which conveyor all the ends of the same group are aligned;

[0037] Figure 6 shows a cross-sectional view of a prior art multi-row coaxial meltblown apparatus highlighting the holes in the intermediate air plate through which air flows;

[0038] Figure 7 Another cross-sectional view of a prior art multi-row coaxial meltblown apparatus, highlighting the receiving orifice of the tube for dispensing the polymeric fluid; and

[0039] Figure 8 An exploded perspective view of a prior art multi-row coaxial meltblown apparatus is shown, showing from bottom to top the following components: an outer air plate, an intermediate air plate, an inner air plate, a cone, a diverter plate, and a second cone for contacting and securely connecting with the extrusion head. DETAILED DESCRIPTION

[0040] In this document, when measurements, values, shapes, and geometric references (such as perpendicularity and parallelism) are associated with "approximately" or other similar terms (such as "almost" or "substantially"), they should be understood to exclude measurement errors or inaccuracies due to production and / or manufacturing errors, especially when the deviation from the relevant value, measurement, shape, or geometric reference is very small. For example, when these terms are associated with a numerical value, it is preferred to indicate that the deviation does not exceed 10% of the numerical value.

[0041] In addition, the terms “first,” “second,” “upper,” “lower,” “primary,” “secondary,” etc. when used do not necessarily indicate an order, a relationship priority, or a relative position, but may only be used to clearly distinguish different components thereof.

[0042] Unless otherwise indicated, as reflected in the following discussion, the terms “process,” “compute,” “determine,” “calculate,” and the like should be deemed to refer to the actions and / or processes of a computer or similar electronic computing device that manipulates and / or transforms data represented in physical form, such as electronic quantities of record of a computer system and / or memory, to similarly represent data represented in physical form as other data of physical quantities in a computer device, record or other information storage, transmission, or display device.

[0043] Unless otherwise stated, the measurements and data reported in this paper should be considered to be in compliance with the International Standard Atmosphere ICAO (ISO 2533:1975).

[0044] With reference to the accompanying drawings, a multi-row coaxial meltblown apparatus according to the present invention is indicated by numeral 1 as a whole.

[0045] As the title suggests, Apparatus 1 includes some of the features of common meltblown equipment as well as other special measures.

[0046] Specifically, the device 1 preferably includes at least one flow divider 2 and a wire outlet device 3 .

[0047] The following description of all components that may be included in the device 1 is based on a cross section along the main plane 1a of the device or a secondary plane 1a' parallel to the main plane 1a, for example Figures 1-4 Of course, such a device 1 and its constituent components also extend along a longitudinal direction 1b perpendicular to the main plane 1a and the secondary plane 1a' or the aforementioned section.

[0048] Therefore, the main plane 1 a and the secondary section plane 1 a ′ are substantially offset from one another along the longitudinal direction 1 b .

[0049] The flow splitter 2 is basically a device adapted to distribute the polymer fluid and the air within the respective conduits to achieve a diffusion path.

[0050] Thus, the diverter 2 is configured to be operatively connected to the cartridge 10 .

[0051] The cassette body 10 is a conventional component of a meltblowing device. Specifically, the cassette body 10 is the part through which polymer fluid and gas are transported to the diverter 2.

[0052] Therefore, the cartridge 10 includes at least one main conduit 10a for conveying polymer fluid and a plurality (eg, a pair) of secondary conduits 10b for conveying gas.

[0053] Therefore, the flow splitter 2 comprises at least one main inlet 20 .

[0054] The main inlet 20 is adapted to be placed in fluid communication with the main conduit 10a. Thus, the main inlet 20 is the portion through which the polymer fluid enters the splitter 2.

[0055] The flow splitter 2 further comprises at least one secondary inlet 21. Preferably, the flow splitter 2 comprises a plurality of secondary inlets 21.

[0056] The secondary inlets 21 are adapted to be placed in fluid communication with the corresponding secondary conduits 10b, respectively. Thus, the secondary inlets 21 constitute the portion through which the gas enters the splitter 2.

[0057] The wire outlet device 3 is preferably in fluid communication with the flow divider 2. Specifically, the wire outlet device 3 receives the polymer fluid and the gas from the flow divider 2.

[0058] Then, the filament discharge device 3 is configured to dispense polymer filaments from the polymer fluid.

[0059] In this respect, the thread discharge device 3 therefore comprises at least one spinneret 4 .

[0060] The spinneret 4 is used to form polymer filaments. In addition, the spinneret 4 is preferably detachably fixed on the splitter 2.

[0061] The spinneret 4 thus comprises at least one group 4'.

[0062] The group 4 ′ is essentially a group of elements. Specifically, the group 4 ′ comprises a plurality of accelerating tubes 40 .

[0063] The accelerating conduit 40 preferably extends parallel to the yarn output direction 4 a.

[0064] The thread outlet direction 4a is preferably defined parallel to the main plane 1a and specifically extends along the main plane 1a.

[0065] Furthermore, the accelerating conduit 40 is basically configured to receive the first polymer fluid from the at least one main inlet 20. Therefore, the accelerating conduit 40 is preferably arranged in fluid communication with the main inlet 20.

[0066] Furthermore, the accelerating conduit 40 is preferably configured to accelerate the first polymer fluid.

[0067] In this respect, in a multi-row coaxial meltblown device, the accelerating conduit comprises tubes 11 or may consist of tubes 11. Thus, these tubes 11 may be releasably fixed to the spinneret 4.

[0068] The tube 11 is well known in the art and is essentially a pipe comprising at least one internal convergent section (in the direction of advancement of the filaments) adapted to accelerate the first polymer fluid transported inside the tube.

[0069] Furthermore, the tube 11 has a generally tubular cylindrical shape and / or is at least partially conical and defines a diameter typically comprised between 0.6 and 1 mm.

[0070] The tube 11 is also used to extend through the wire outlet device 3, such as Figure 1 and Figure 3 shown.

[0071] If the tube 11 is not integral with the spinneret 4, then the support typically comprises the housing.

[0072] The housing may be a substantially hollow cavity, comprising at least one shoulder or step, in which the tube 11 may be at least partially housed.

[0073] In practice, the tube 11 preferably comprises a base portion and a stem portion.

[0074] The base is preferably configured to be inserted into one of the receptacles.

[0075] The rod preferably extends parallel to the threading direction 4a, ie extends in a perpendicular direction to the section plane. Thus, the first polymer fluid from the main inlet 20 essentially enters the base of the tube 11 and is accelerated along the rod.

[0076] Thus, the tube 11 is essentially in fluid communication with at least one main inlet 20 and is configured to distribute the polymer fluid.

[0077] Then, the accelerating ducts 40 can be arranged in one or more rows extending parallel to the longitudinal direction. In particular, they are usually distributed in a regular manner to form orderly rows along the longitudinal direction and along each cross-sectional plane of the device 1.

[0078] Sometimes, adjacent rows of accelerating ducts 40 are staggered relative to each other along the longitudinal direction 1 b , thereby achieving a generally checkerboard-shaped configuration.

[0079] The group 4 ′ further comprises a first hole 41 and a second hole 42 .

[0080] The first hole 41 preferably extends parallel to the yarn output direction 4a. In addition, the first hole is preferably centered relative to the acceleration tube 40 along the yarn output direction 4a. Then, the first hole 41 is preferably configured to accommodate each portion of the corresponding tube 11. As previously described, the tube 11 is configured to distribute the polymer fluid.

[0081] Thus, the first hole 41 is adapted to allow the polymer fluid to pass through the tube 11 .

[0082] The second holes 42 are preferably spaced apart from the first holes 41. They are particularly suitable for allowing air or gas to pass through. Alternatively, the second holes 42 can coincide with the first holes 41 and accommodate the tube 11 while maintaining a gap outside the tube 11 to allow air or gas to pass through.

[0083] Generally speaking, the second hole 42 also extends parallel to the thread output direction 4 a.

[0084] Thus, the first hole 41 is substantially adapted to receive a portion of the stem of the tube 11. At the same time, the second hole 42 is adapted to allow the passage of air or gas.

[0085] The group 4 ′ also comprises a slit 43 .

[0086] The slit 43 extends transversely to the yarn exit direction 4a between the first hole 41 and the second hole 42. In other words, the accelerating conduit 40 and the second hole 42 are connected by the tube 11 and separated by the slit 43 transverse to the tube 11 itself. The slit 43 is then in fluid communication with the second hole 42.

[0087] Advantageously, the slits 43 extend from one side to the other in the group 4'. This means that the slits 43 extend in a plane transverse to the yarn outlet direction 4a, starting from an opening on one side of the group 4' and ending at an opening on the opposite side of the group 4'.

[0088] Therefore, the diverter 2 advantageously comprises a housing 22. The housing 22 is essentially a groove formed in the support 2 and extending in the longitudinal direction 1 b.

[0089] The housing 22 is also preferably open on at least one side in the longitudinal direction 1b so that the spinneret 4 can be removed and inserted by sliding, preferably along the longitudinal direction 1b and along the side including the opening. The opening is also preferably reclosable by a closing device, such as a plate that can be reclosed by interlocking or sliding in a direction perpendicular to the longitudinal direction 1b.

[0090] The housing 22 is configured to accommodate the spinneret 4. Thus, when the spinneret 4 is used in the apparatus 1, the flow divider 2 substantially surrounds the spinneret 4. The spinneret 4 essentially serves as an insert or cartridge that can be inserted into the support 2. Therefore, preferably, the secondary inlet 21 is in fluid communication with the housing 22 via a conduit extending transversely to the yarn output direction 4a and, in particular, transversely to the longitudinal direction 1b.

[0091] Thus, the slit 43 is in fluid communication with the secondary inlet 21 and is also configured to pass air or gas from the secondary inlet 21 to the second aperture 42 .

[0092] In addition to what has been described, the apparatus 1 may further comprise a guide 5. Specifically, the filament discharge device 3 comprises a guide 5. The guide 5 is actually adapted to receive gas to guide the polymer filaments leaving the filament discharge device 3, and is preferably located downstream of the spinneret 4.

[0093] The guide 5 is very similar to a common external air plate, but there are some differences.

[0094] The guide 5 is preferably detachably fixed to one or more of the flow divider 2 and the spinneret 4. Preferably, the guide 5 is detachably fixed to the fixed support 2, for example, by means of a restraining device known per se. The guide 5 then acts as a cap that confines the spinneret 4 in the housing 22 within the flow divider 2.

[0095] Preferably, the guide 5 comprises, for each group 4 ′, one or more third holes 50 .

[0096] The third hole 50 is preferably centered relative to the first hole 41. Furthermore, the third hole is adapted to receive a portion of the tube 11 from the first hole 41 of the spinneret 4 and in communication with the second hole 42. Thus, the third hole 50 receives a portion of the tube 11 while allowing air or gas to pass around the tube 11. In other words, the third hole 50 is also in fluid communication with the second hole 42. To achieve this characteristic, the third hole 50 need only be sized larger relative to the tube 11, thereby creating a gap around the tube 11 for air to pass through.

[0097] The guide member 5 further includes a seat portion 51 .

[0098] The seat 51 is advantageously configured to partially house the spinneret 4 or at least one group 4 ′. In this way, the guide 5 can be anchored to the spinneret 4 .

[0099] Specifically, the seat 51 is preferably defined by two edges 51a. The two edges 51a are advantageously positioned on opposite sides relative to the thread-out direction 4a. Thus, the two edges extend parallel to the thread-out direction 4a and preferably parallel to the longitudinal direction 1b. Consequently, the seat 51 also extends as a whole parallel to the longitudinal direction 1b.

[0100] Thus, the spinneret 4 or each group 4 ' comprises at least two grooves 48. The two grooves 48 are advantageously configured to accommodate the edges 51a. Then, when the spinneret 4 ' is placed on the guide 5 (or vice versa), the edges 51a are essentially introduced into the grooves 48, so that the spinneret 4 is anchored to the guide 5.

[0101] The slots 48 extend in the spinneret 4 or in each group 4 ′, preferably parallel to the exit direction 4 a at the end through which the slits 43 pass.

[0102] Furthermore, the edge 51a is preferably formed in a shape that converges relative to the direction of exit of the filaments 4a and is appropriately opposite to the direction of advancement of the filaments. This shape facilitates insertion of the edge into the groove 48 and, therefore, also facilitates alignment of the third hole 50 with the tube 11, for example, when assembling the device 1.

[0103] The spinneret 4 preferably comprises further features.

[0104] Advantageously, in practice, the spinneret 4 also comprises one or more components selected from the further group 4' and at least one tip 4".

[0105] If there is an additional group 4', it is distinct, separate and side-by-side with the other groups 4'. The guide 5 can then be provided with a third hole 50 in which the tubes 11 of the additional group 4' are also received. Alternatively, the guide 5 can comprise two distinct and separate parts, each comprising a third hole 50 for docking with a corresponding group 4'.

[0106] If present, the tip 4'' is adjacent on both sides to the group 4' and comprises at least one main outlet 40a suitably situated at the centre of gravity of the tip 4'' and therefore connected to the tip of the tip 4''.

[0107] The main outlet 40a is configured to deliver the polymer fluid parallel to the yarn output direction 4a.

[0108] Then, if the tip 4" is present, the spinneret 4 also includes a pair of secondary outlets 41a.

[0109] The secondary outlets 41 a are preferably arranged at opposite sides with respect to the tip 4 ″. In addition, the secondary outlets 41 a are configured to deliver gas toward the guide 5 .

[0110] If a tip 4" is present, the guide 5 preferably comprises an air knife 52. The air knife 52 is basically adapted to deliver air or gas to the tip of the tip 4". The air knife 52 then defines an outlet 52a.

[0111] The outlet 52a is preferably in fluid communication with the secondary outlet 41a. In addition, the outlet 52a extends parallel to the yarn outlet direction 4a at the main outlet 40a.

[0112] The device 1 then also comprises a conveying device 6 .

[0113] The transfer device 6 is advantageously configured to fluidically connect at least one secondary inlet 21 to two opposite ends of the slits 43 of one group 4 ′ and to connect another secondary inlet 21 to two opposite ends of the slits 43 of another group 4 ′ or to a pair of secondary outlets 41 a .

[0114] Furthermore, in one embodiment, the transfer device 6 may also advantageously be configured to fluidically connect the main inlet 20 to the acceleration duct 40 and / or the main outlet 40a of each group 4 ′.

[0115] Alternatively, the flow splitter 2 may include a plurality of main inlets 20. The transfer device 6 may then be configured to connect a main inlet 20 to one group 4' of accelerating ducts 40 and another main inlet 20 to another group 4' of accelerating ducts 40 or to the main outlet 40a.

[0116] The transfer device 6 then enables the polymer fluid and the gas to be conveyed to the outlet device 3 of the device 1 , in particular to the spinneret 4 , using at least partially conventional equipment.

[0117] In more detail, the transfer device 6 comprises at least one main access opening 60 .

[0118] The main inlet port 60 is in fluid communication with the main inlet 20. Thus, the main inlet port 60 is adapted to receive the polymer fluid from the main inlet 20.

[0119] Furthermore, the transmission device 6 includes a plurality of main branches 61 .

[0120] The main branches 61 are all in fluid communication with the main inlet 60. Furthermore, each main branch 61 is in fluid communication with the accelerating ducts 40 of the corresponding group 4' and / or the corresponding main outlet 40a.

[0121] The main branch 61 then transfers the polymer fluid from the main inlet 60 to the accelerating conduit 40 and possibly to the main outlet 40a.

[0122] The transfer device 6 advantageously also comprises a plurality of secondary inlet openings 62 .

[0123] Each primary inlet port 62 is in fluid communication with a corresponding secondary inlet port 21. Each primary inlet port 62 then receives a gas, such as air, from the secondary inlet port 21. Furthermore, the delivery device 6 comprises a plurality of pairs of secondary branches 63.

[0124] In each pair, all secondary branches 63 are in fluid communication with a corresponding secondary inlet 62. Furthermore, in the same pair, each secondary branch 63 is in fluid communication with a corresponding end of a slit 43 of a group 4' and / or a secondary outlet 41a of a pair of secondary outlets 41a.

[0125] To achieve this configuration, Figures 1 to 4 In the preferred, but not exclusive, embodiment shown, the transfer device 6 can be completely contained in the diverter 2 .

[0126] Therefore, in this case, the primary inlet port 60 preferably corresponds to the primary inlet 20 , and each secondary inlet port 62 corresponds to a respective secondary inlet 21 .

[0127] Then, for each group 4 ′, the spinneret 4 may comprise a first main distribution channel 44 . The first main distribution channel 44 is configured to connect the main branch 61 and the acceleration duct 40 in fluid communication.

[0128] The spinneret 4 may then comprise, for each group 4', a pair of first secondary distribution channels 45. The first secondary distribution channels 45 are preferably each configured to fluidically connect a respective secondary branch 63 of the same pair of secondary branches 63 with the end of a respective slit 43.

[0129] Furthermore, the spinneret 4 may include a primary distribution channel 46 and a pair of secondary distribution channels 47 for each tip 40 .

[0130] The main distribution passage 46 is preferably configured to fluidly connect the main branch 61 and the main outlet 40a.

[0131] Each of the pair of secondary distribution channels 47 is configured to fluidly connect a corresponding secondary branch 63 with a corresponding secondary outlet 41 a of the same pair of secondary outlets 41 a.

[0132] Thus, in this embodiment, the spinneret 4 has conventional features.

[0133] The splitter 2 can be integrated or divided into two different modules.

[0134] For example, flow divider 2 can comprise support plate and diverter plate.As everyone knows, support plate is the interface element that is usually arranged between cassette body 10 and diverter plate.Diverter plate is the connecting plate between support plate and spinneret 4.

[0135] Advantageously, the conveying device 6 can be completely contained in one or more of the support plate and the diverter plate. This means that the conveying device 6 can be formed in only one of the support plate and the diverter plate, or can be partially formed in the support plate and partially formed in the diverter plate.

[0136] As already explained, the description in this specification is based on a section through the device perpendicular to the main direction 1 a .

[0137] However, the device 1 also extends along a longitudinal direction 1 b .

[0138] Thus, the device 1 may define a longitudinal plane 1 c along which at least a portion of the device 1 , in particular the flow diverter 2 and the wire discharge device 3 , extends.

[0139] The longitudinal plane 1 c is parallel to the longitudinal direction 1 b and, in more detail, is a virtual or even physical interface plane to which the ends of the primary branch 61 and the secondary branch 63 are connected.

[0140] In detail, each main branch 61 has a main end portion 61 a .

[0141] The main end portion 61 a is substantially opposite the main inlet port 60 .

[0142] Each secondary branch 63 has a secondary end 63 a , which is preferably opposite to the secondary inlet 62 .

[0143] The ends 61a, 63a are then distributed on the main plane 1b so that for each group 4' or tip 4", and for each set comprising a main end 61a and a pair of adjacent secondary ends 63a, at least the secondary ends 63a are mutually staggered with respect to a direction perpendicular to the longitudinal direction 1b, as Figure 5a shown.

[0144] Alternatively, all the ends 61a, 63a may be mutually staggered with respect to a direction perpendicular to the longitudinal direction 1b, such as Figure 5b shown.

[0145] In other words, the ends 61a, 63a located upstream of the same group 4' or tip 4" and adjacent to each other belong to the same set.

[0146] In more detail, preferably, for each group 4 ′ or tip 4 ″ and for each set, at least one main end 61a and one secondary end 63a of the same group are aligned with each other along the direction of extension 6a. The direction of extension 6a is transverse to the main direction 1 a.

[0147] Furthermore, the extension directions 6a are preferably parallel to each other, e.g. Figure 5b As clearly shown in .

[0148] This configuration advantageously prevents the branches 61 , 63 from intersecting each other.

[0149] In summary, the device 1 may define further detailed characteristics.

[0150] For example, the spinneret 4 may include at least one seat 49 .

[0151] The seat 49, if present, is configured to house at least one filter 12. The filter 12 may be a sponge-like element adapted to filter the polymer fluid entering the spinneret 4. Therefore, the seat 49 is preferably arranged near the flow divider 2.

[0152] In particular, a seat 49 may be arranged between each main branch 61 and the corresponding main distribution channel 44 , 46 .

[0153] Of course, the device 1 may further include a filter 12 and a cartridge 10 .

[0154] The operation of the above-mentioned multi-row coaxial meltblown device 1 is structurally similar to the operation of any multi-row coaxial meltblown device.

[0155] However, since the multi-row coaxial meltblown apparatus 1 can utilize multiple side-by-side groups and / or tips, it allows for the production of multiple rows of filaments that are parallel to each other and to the filament outgoing direction 4a.

[0156] The multi-row coaxial meltblown apparatus 1 according to the present invention achieves important advantages.

[0157] In fact, the multi-row coaxial meltblown device 1 allows the production of multiple rows of polymer filaments. The possibility of using multiple side-by-side groups and / or tips enables the quality of the nonwoven to be improved and the production speed to be increased.

[0158] In addition, compared with the aforementioned advantages, the multi-row coaxial meltblown device 1 can reduce the number of components required to manufacture multiple rows of filaments and can also utilize at least a portion of the prior art equipment, because the prior art equipment can include at least a conventional box body and may also include a conventional diverter 2.

[0159] Therefore, the device 1 can reduce the cost of equipment modification and is more economical from the perspective of both operation and maintenance.

[0160] Furthermore, the device 1 avoids axial deviations between the tube housed in the diffuser portion and the holes in the device component, since the spinneret 4 can be cleaned from the side through the slot 43 without having to remove the tube 11 from the first hole 41 as in prior art devices.

[0161] Furthermore, the apparatus 1 can be easily converted to produce different types of nonwoven fabrics, since the conversion can be accomplished simply by replacing the spinnerets in the housing 22 .

[0162] Various modifications can be made to the present invention, all of which fall within the scope of the inventive concept defined by the claims.

[0163] In this context, all details may be replaced by equivalent elements and any materials, shapes and sizes may be used.

Claims

1. A multi-row coaxial meltblown device (1), comprising: A flow diverter (2) is configured to be operatively connected to the cartridge (10), and the flow diverter comprises: at least one main inlet (20) adapted to be in fluid communication with the main conduit (10a) of the cartridge (10) and adapted to convey a polymer fluid, and a plurality of secondary inlets (21), each of the plurality of secondary inlets being adapted to be in fluid communication with a corresponding secondary conduit (10b) of the cartridge (10) for conveying gas; A filament discharge device (3) is in fluid communication with the flow divider (2) and is configured to distribute polymer filaments formed from the polymer fluid, the filament discharge device (3) comprising at least: A spinneret (4) adapted to form the polymer filaments and removably secured to the flow divider (2), the spinneret (4) comprising at least one group (4'), the at least one group (4') further comprising: A plurality of accelerating pipes (40) extending along the wire-out direction (4a), and comprising a tube (11) in fluid communication with at least one main inlet (20), said tube (11) being configured to distribute said polymer fluid, a first hole (41), the first hole extending parallel to the wire-exit direction (4a) and arranged centrally relative to the accelerating pipe (40) along the wire-exit direction (4a), the first hole (41) being configured to accommodate at least a portion of the tube (11), a second hole (42) extending parallel to the thread-out direction (4a) and adapted to allow passage of air or gas, and a slit (43) extending in a transverse direction to the wire-exiting direction (4a), and being located between the accelerating conduit (40) and the first hole (41), and being in fluid communication with the second hole (42), A guide member (5) adapted to receive gas to guide the polymer filaments discharged from the filament outlet device (3) and detachably fixed to the diverter (2) and / or the spinneret (4), and wherein the guide member (5) Each of the groups (4') includes a plurality of third holes (50), the third holes (50) being centrally arranged relative to the first holes (41) and communicating with the second holes (42), the third holes (50) being configured to receive a portion of the tube (11) while allowing air or gas to pass around the tube (11); It is characterized in that The spinneret (4) further comprises one or both of the following: an additional group (4'), said additional group being distinct, separate and side-by-side with the other said groups (4'); at least one tip (4") arranged alongside the group (4') and comprising at least one main outlet (40a) configured to deliver the polymer fluid parallel to the filament exit direction (4a); And in the case where the tip (4") is included, then: The spinneret (4) further comprises a pair of secondary outlets (41a) arranged on opposite sides relative to the tip (4") and configured to deliver the gas to the guide (5); The guide member (5) includes an air knife (52), the air knife having an outlet (52a), the outlet (52a) being in fluid communication with the secondary outlet (41a) and extending parallel to the wire outlet direction (4a) at the primary outlet (40a); The device (1) comprises a conveying device (6), which is configured at least to: placing the secondary inlet (21) in fluid communication with two opposite ends of the slits (43) of the set (4'); The other of the secondary inlets (21) is fluidically connected to the two opposite ends of the slits (43) of the other of the groups (4') or the pair of secondary outlets (41a).

2. Apparatus (1) according to claim 1, wherein the diverter (2) comprises a plurality of main inlets (20), and the conveying device (6) is configured to connect a main inlet (20) to the fluid of an accelerating duct (40) of one of the groups (4'), and to connect another main inlet (20) to the fluid of an accelerating duct (40) of another group (4') or to the main outlet (40a).

3. Apparatus (1) according to claim 1, wherein said conveying means (6) is further configured to connect said main inlet (20) to the acceleration duct (40) and / or said main outlet (40a) of each said group (4') in fluid communication.

4. The apparatus (1) according to claim 1, wherein the conveying device (6) comprises at least one main inlet (60) in fluid communication with the main inlet (20), a plurality of main branches (61), all of which are in fluid communication with the main inlet (60) and are respectively in fluid communication with the corresponding accelerating ducts (40) of the group (4') and / or the corresponding main outlet (40a), a plurality of secondary inlets (62), each of which is in fluid communication with the corresponding secondary inlet (21), and a plurality of pairs of secondary branches (63); In each pair of secondary branches (63), the secondary branches (63) are fluidically connected to the corresponding secondary inlet (62), and each of the secondary branches (63) is fluidically connected to the corresponding end of the slit (43) of the group (4') and / or the corresponding secondary outlet (41a) in the pair of secondary outlets (41a).

5. Apparatus (1) according to claim 4, wherein the conveying means (6) is completely contained in the diverter (2), the primary inlet (60) corresponds to the primary inlet (20), each of the secondary inlets (62) corresponds to a respective secondary inlet (21), and the spinneret (4) comprises: a first main distribution channel (44) for each of the groups (4'), the first main distribution channel being configured to be in fluid communication between the main branch (61) and the acceleration duct (40), and a pair of first secondary distribution channels (45) for each of the groups (4'), each of the first secondary distribution channels (45) being configured to be in fluid communication between a corresponding secondary branch (63) in the same pair of secondary branches (63) and an end of a corresponding slit (43), and / or a second main distribution channel (46) and a pair of second secondary distribution channels (47) for the tip (4"), the second main distribution channel being configured to provide fluid communication between the main branch (61) and the main outlet (40a); Each of the second secondary distribution channels (47) is configured to provide fluid communication between a corresponding secondary branch (63) in the same pair of secondary branches (63) and a corresponding secondary outlet (41a) in the same pair of secondary outlets (41a).

6. Apparatus (1) according to claim 1, wherein the diverter (2) comprises a support plate and a diverter plate; and wherein the conveying device (6) is completely contained in the support plate and / or the diverter plate.

7. An apparatus (1) according to claim 4, wherein the diverter (2) and the wire outlet device (3) extend mainly along the longitudinal direction (1b); wherein each main branch (61) has a main end (61a), which is opposite to the main entry port (60); wherein each secondary branch (63) has a secondary end (63a), which is opposite to the secondary entry port (62); and wherein the ends (61a, 63a) are distributed on a longitudinal plane (1c) parallel to the longitudinal direction (1b), so that for each of the groups (4') or the tips (4"), and for each set comprising the main end (61a) and a pair of adjacent secondary ends (63a), at least the secondary ends (63a) are staggered with respect to a direction perpendicular to the longitudinal direction (1b).

8. Device (1) according to claim 7, wherein the ends (61a, 63a) are distributed in the longitudinal plane (1c) so that all the ends (61a, 63a) of the same group are offset relative to each other with respect to a direction perpendicular to the longitudinal direction (1b).

9. The device (1) according to any one of claims 7 to 8, wherein for each of the groups (4') or tips (4") and for each of the sets, at least one of the main ends (61a) and one of the secondary ends (63a) are aligned with one another along a direction of extension (6a) transverse to the main direction (1a).

10. Apparatus (1) according to claim 1, wherein the spinneret (4) comprises at least one seat (49) configured to accommodate at least one filter (12) and arranged in the vicinity of the diverter (2).

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