Wire mesh unit

Abstract

Wire mesh unit (1) with at least one wire mesh layer (2) made of warp wires (3) and weft wires (4), wherein the warp wires (3) and the weft wires (4) form meshes (5) and span a mesh surface (6), characterized in that a pore size (7) of at least some of the meshes (5) of the wire mesh unit (5) is changed by a coating (8), wherein the pore size (7) is selectively influenced and thus defined by the coating (8), wherein the coating (8) is selectively formed on the mesh surface (6) and wherein the coating (8) is applied more thickly on at least a first section (11) than on a second section (12).

Description

[0001] The present invention relates to a wire mesh unit having at least one wire mesh layer made of warp wires and weft wires, wherein the warp wires and the weft wires form meshes and span a fabric surface.

[0002] In particular, the wire mesh unit according to the invention is used as a filter unit for filtration, preferably for fine filtration. For example, DE 295 07 080 U1 describes a molded part made of at least one layer of wire mesh that can be used in the field of filtration. Embedding the molded part in a cured coating is intended to prevent individual wires from becoming detached from the mesh.

[0003] A wire mesh unit according to the invention can be used, for example, to filter the oil flow for an internal combustion engine. It can also be used to filter exhaust gases from combustion processes, for example.

[0004] Use in this area requires a seal around the edge of the filter or filter unit to prevent crossflow or leaks. For this purpose, wire mesh and seals are used in conjunction with a holder. The production of such a filter unit is therefore complex.

[0005] Typically, the field of application of a wire mesh unit according to the invention is in the field of fine filtration for filtration with pore sizes starting at about 10 or 20 micrometers and ending at 300 micrometers or 400 micrometers.

[0006] It is therefore the object of the present invention to provide a wire mesh unit with which a simpler production of a filter unit is possible.

[0007] This object is achieved by a wire mesh unit having the features of claim 1 and by a filter unit having the features of claim 18. Preferred developments are the subject of the subclaims. Further advantages and features of the present invention will become apparent from the general description and the description of the exemplary embodiments.

[0008] A wire mesh unit according to the invention comprises at least one wire mesh layer made of warp wires and weft wires. The warp wires and weft wires form mesh meshes and span a mesh surface. A coating alters the pore size of at least some of the mesh meshes of the wire mesh unit. The pore size is specifically influenced by the coating and thus defined. Furthermore, the coating is selectively applied to the mesh surface, with the coating being applied more densely to at least a first section than to a second section.

[0009] The wire mesh unit according to the invention has many advantages. A significant advantage is that the pore size of the mesh can be specifically influenced and thus precisely adjusted after weaving. This makes it possible to achieve very fine and ultrafine pores even when using relatively thick warp and weft wires, without using correspondingly fine wires.

[0010] The wire mesh layer or a wire mesh layer of a wire mesh unit according to the invention can have a wide variety of weave types. The mesh can have open meshes and thus open openings perpendicular to the surface. However, it is also possible for the meshes to be tightly woven. The wire mesh layer can be designed as a dutch weave, which only results in skewed open pores, while the wire mesh layer perpendicular to the mesh surface is opaque. This means that the mesh size can be reduced to 0. Due to the three-dimensionality of a wire mesh, even a dutch weave has open pores with a small opening width, although the open pores are then aligned obliquely to the mesh surface.

[0011] In many cases, a large open area or a high proportion of open area in relation to the filter surface is desired for filter applications. The wire gauge of the warp and weft wires can be any size. Both the same and different warp and weft wires are possible.

[0012] Particularly preferably, in the wire mesh unit according to the invention, the pore size of only some of the meshes of the wire mesh unit is deliberately changed. The pore size of at least some of the meshes can be deliberately reduced to zero, thus preventing flow there.

[0013] It is also preferred that the pore size of at least some meshes be modified differently than the pore size of other meshes. For example, some pores can be specifically coated, while the wires of another mesh remain uncoated, thus maintaining the original pore size. However, it is also possible for the wires of some meshes to be coated more heavily than the wires of another mesh.

[0014] A galvanic coating process is particularly preferred. This means that the coating is preferably galvanized. However, another type of coating is also possible, for example, a paint coating or other plastic coating or the like.

[0015] Electroplating offers significant advantages, as the thickness of the coating can be adjusted very precisely and finely by adjusting the duration of the electroplating treatment and the other conditions. For example, in particularly fine wire mesh layers, the mesh size can be specifically reduced from 20 micrometers to 15 micrometers or similar. It is also possible to specifically adjust the pore size of a mesh with an original mesh size of 70 micrometers to 65 micrometers, 60 micrometers, or similar.

[0016] According to the invention, the coating is selectively applied to the fabric surface, or the coating is selectively formed on the fabric surface, with the coating being applied more densely to at least a first section than to a second section. In this case, no coating at all may be provided in the second section. It is also possible for the wire mesh layer as a whole to have a first coating layer and for sections of the wire mesh layer to have a second selectively applied coating layer.

[0017] In particular, the coating is applied only in sections of the wire mesh layer. This opens up a wide range of possibilities, as sections of the wire mesh layer have different pore sizes.

[0018] In particularly preferred embodiments, at least some of the meshes are sealed with a coating material. The coating material is particularly preferably applied in such a manner and thickness that the coating enables a seal. As a result, the coating can provide a sealing function through the wire mesh unit in the first section. The coating can also prevent crossflows. The coating can also enable a tight fit against another component in the transverse direction.

[0019] In particular, the meshes are closed by the coating, resulting in a pore size of 0. For example, on a specific section of the wire mesh layer, the pore size can be specifically adjusted by, for example, a galvanic coating, and on another section of the wire mesh unit, the pores are closed by the coating, resulting in specific filter areas or filter sections.

[0020] In preferred embodiments, the wire mesh unit is compacted in at least one region. For example, the wire mesh unit can be compacted by rolling, local pressing, and / or calendering. It is possible and preferred that the local compaction of the wire mesh unit in one region locally closes the pores.

[0021] This makes it possible for a small pore size to remain after the weaving process and subsequent coating, which is then reduced in the compacted area to such an extent that the wire mesh unit provides a closed surface in this area. Such measures allow the wire mesh unit to provide one or more filter sections while simultaneously providing a fluidically tight receiving area or section, allowing the wire mesh unit to be tightly secured.

[0022] In preferred embodiments, the compacted area is, in particular, punched, partially pressed, or pressed, and / or provided with the coating. The coated area can be subsequently compacted, or the coated area can be punched or partially pressed. The compacted area can serve as a seal.

[0023] In preferred embodiments, the coating comprises two or more coating layers at least in certain sections. For example, a central filter area may have only one coating layer, while a sealing section may have several coating layers, so that the pores of the fabric mesh there are completely closed.

[0024] In particular, the wire mesh layer has at least one filter section on the mesh surface. Multiple filter sections are also possible. Particularly preferably, the wire mesh unit has open pores on the filter section and closed pores on a holding section adjacent to the filter section. It is possible and preferred for the holding section to surround the filter section.

[0025] Such a design enables a flexibly usable wire mesh unit with a simple manufacture, in which both a filter section and the holding section required for holding are formed on the mesh surface, which provides a fluidically tight mesh section.

[0026] Preferably, at least one recess is provided on the fabric surface for fastening or aligning the wire mesh layer.

[0027] The wire mesh unit can have a material reservoir provided by the coating, which can serve, for example, as a solder reservoir for contacting other components. For example, such a material can be provided for soldering the wire mesh layer to another electrical component.

[0028] In preferred embodiments, the coating comprises at least one coating layer that consists at least substantially of catalytic materials. In particular, the coating layer or at least one coating layer consists of nickel, chromium, gold, silver, copper, titanium, platinum, palladium, or tin. A combination of the listed materials is also possible.

[0029] A thickness of the coating is preferably between 1 micrometer and 500 micrometers and more preferably between 1 micrometer and 200 micrometers.

[0030] In all cases, at least some of the wires of the wire mesh layer are preferably made of at least one metal. Particularly preferably, all devices of the wire mesh layer are made of metal. However, it is also possible for at least some of the wires of the wire mesh layer to be made of a non-metal. Preferably, the non-metal wires have an electrically conductive surface coating. In this case, the non-metal wires can also be provided with a galvanic surface coating. The cross-section of the wires can be round, square, or otherwise shaped. In principle, any desired contour is possible. For optimally reproducible filter conditions, wires that are homogeneous over their length are preferably used.

[0031] It is possible and preferred for the wire mesh unit to comprise a layered composite of at least two wire mesh layers. The two wire mesh layers can be connected to one another, for example, by means of a galvanic coating. The wire mesh layers of a layered composite can have different mesh parameters and different mesh sizes, wire diameters, pitches, etc. Two wire mesh layers can also be made of different materials. The orientation of two wire mesh layers relative to one another can be different. For example, the warp wires of two wire mesh layers can be aligned parallel to one another or at any angle to one another.

[0032] In all cases, at least some wires may consist of monofilaments or multifilaments.

[0033] With the present invention, the pore size is specifically reduced by electroplating the mesh. Sufficient material is applied to create a sealing surface through compaction. This provides a fine filter surface on the one hand, and a dense receiving surface for the wire mesh unit on the other. The cost of manufacturing a filter unit is significantly reduced because the wire mesh unit serves as both a receiving surface and a filter.

[0034] Coating the wire mesh layer does not fundamentally change the material properties of the mesh wires, but rather specifically adjusts the filter properties. The coating can also provide corrosion protection, for example. An additional, separate sealing lip, which in the prior art often has to be molded onto the mesh with plastic or the like, is eliminated with the present invention, as the wire mesh unit can be designed to be locally sealed. The wire mesh unit can be coated with a wide variety of metals in one or more layers.

[0035] By applying the coating, the pore size can be reduced in a targeted and reproducible manner, for example, to 5 micrometers. Edge compaction then completely closes the pores. Preferably, the wire mesh layer is first produced and then electroplated, in particular. This can be followed by pressing, calendering, or similar processes to seal retaining sections.

[0036] The use of such a filter unit is suitable, for example, in the oil flow of the engine in order to reliably filter the fuel.

[0037] The selective coating of a wire mesh layer on the mesh surface enables the use as a filter unit, eliminating the need for a separate holder and seal.

[0038] The stability of the wire mesh layer can also be increased through a galvanic surface coating. For example, a nickel layer can be applied to increase stability, followed by a copper layer to selectively seal the pores, for example, after a pressing process.

[0039] Preferably, a coating layer is selectively applied that is so soft that, after a pressing process, the coating layer enables a tight seal. This also reliably prevents crossflows. This allows the wire mesh unit to be used directly as a filter unit. The wire mesh unit provides the holder, the mount, and the filter. A separate seal is not necessary.

[0040] A filter unit according to the invention consists of a wire mesh unit with at least one wire mesh layer made of warp wires and weft wires, wherein the warp wires and weft wires form meshes and span a mesh surface. The pore size of at least some of the meshes of the wire mesh unit is modified by a coating.

[0041] The wire mesh layer of the filter unit has, in particular, at least one filter section on the mesh surface. Open pores are preferably provided on the filter section. On a holding section surrounding the filter section, the pores are, in particular, closed. The holding section serves to hold the filter unit. Preferably, at least one recess for fastening or aligning the filter unit is provided on the mesh surface. In particular, the holding section can be compacted entirely or in certain regions.

[0042] In further developments, the wire mesh unit is designed according to one or a combination of several of the previously described embodiments.

[0043] The invention can also be used to provide a wire mesh unit with a defined, modified pore size. The pore size depends on the wire diameters of the warp and weft wires. For example, fine pores cannot be achieved with thick wires because the woven wire can only be deformed to a limited extent. In an open, uncoated mesh, the mesh size cannot generally be smaller than the diameter of the woven wire (warp wire or weft wire).

[0044] For example, very thin wires are generally used to manufacture fine wire mesh units in order to provide a high open filter surface with defined pore sizes. Wire mesh with a mesh size of 20 micrometers and a wire diameter of 20 micrometers, for example, has a mesh count of 635. This means there are 635 warp and weft wires per inch of length or width of the wire mesh. Weaving such a fine wire mesh is very complex and time-consuming. This is why conventional fine and ultra-fine wire meshes are not cheap to produce. If the filter fineness needs to be even lower, even thinner wires with a diameter of 16 µm or, for example, 14 µm can be used. However, this further increases the manufacturing effort.Furthermore, the manufacturing process becomes significantly more error-prone, since, for example, with a fabric width of just 100 mm, 2,500 individual warp wires must be precisely guided to the weaving machine. If even a single wire is incorrectly threaded or guided, the fabric exhibits a continuous weaving defect and may even be unusable. The invention allows for a defined reduction in pore size without changing the strength or thickness of the warp and weft wires. The invention also enables the provision of a wire mesh unit that can increase the filter fineness of ultrafine fabrics.

[0045] Further advantages and features of the present invention will become apparent from the embodiments which are explained below with reference to the accompanying figures.

[0046] The figures show: Fig. 1 a schematic plan view of a wire mesh unit designed as a filter unit; Fig. 2 a schematic cross-section through the wire mesh unit according to Fig. 1; Fig. 3 a highly schematic cross-section through a wire mesh layer; Fig. 4 shows another highly schematic cross-section through another layer of wire mesh; Fig. 5 is a highly schematic plan view of a wire mesh unit; and Fig. 6 another schematically illustrated wire mesh unit with two wire mesh layers.

[0047] With reference to the figures, exemplary embodiments of the invention are explained below, wherein Fig. 1 shows a schematic plan view of a wire mesh unit 1 designed as a filter unit 100. The filter unit 100 or the wire mesh unit 1 here consists of a wire mesh layer 2, which provides a first section 11 and a second section 12 on the mesh surface 6.

[0048] The wire mesh unit 1 has a filter section 22 as the first section 11 and a holding section 21 as the second section 12. Here, the wire mesh unit 1 consists of the holding section 21 and the filter section 22. Two recesses 16 are provided in the holding section 21 to receive the filter unit 100 in a defined manner on another component and to fasten it there, for example, by screws or the like.

[0049] The wire mesh unit 1 essentially comprises an initially homogeneous wire mesh layer 2 which consists of mesh meshes 5 over the entire surface of the mesh 6, which meshes are formed by warp wires 3 and weft wires 4.

[0050] After weaving the wire mesh layer 2, the wire mesh layer 2 is locally selectively provided with a coating 8 (cf. Fig. 5) in order to specifically influence the pore size 7 of the fabric meshes 5 in the first section 11 and the second section 12. Here, sufficient material is coated in the holding section 21 that, after the subsequent compaction process in the second section 12, the pore size 7 is reduced to 0, so that the holding section 21 is fluidically impermeable.

[0051] Such a filter unit 100 is very advantageous because it consists essentially of only one single component, namely the wire mesh layer 2, which is selectively coated. The second section is then compacted.

[0052] The pores 9 on the filter section 22 are open, while the pores 10 circled by dashed lines in the holding section 21 are closed.

[0053] Fig. 2 shows a sectional side view of the filter unit 100 according to Fig. 1. The filter unit 100 consists of a wire mesh unit 1. Section 12, as the holding section 21, is compacted, so that the thickness of the wire mesh layer 2 in section 12 is reduced by preferably 10% to 40%. The compaction further enhances the sealing effect. Furthermore, the rigidity of section 12 is increased. At least one recess 16 can be formed on the holding section 21 to facilitate screwing or fastening to other components. Two recesses 16 can serve to determine the orientation of the filter unit.

[0054] Fig. Figure 3 shows a schematic cross-section through a wire mesh layer 2, with the warp wires shown hatched. In the example shown here, non-metallic wires 25 and metal wires 26 are provided, alternating as warp wires. However, it is also possible for all warp wires to be made of metal or, if necessary, also of non-metal. If a galvanic coating is to be applied, it is advantageous if non-metallic wires are first provided with a metallic surface coating.

[0055] In the outer areas of the Fig. The wire mesh layer 2 shown in Figure 3 contains the second section 12, to which a coating layer 14 has been galvanically applied to the wire mesh layer 2. The first section 11 is provided in the central area and serves, for example, as a filter section 22, and in which open pores 9 are provided. To prevent galvanic coating in the first section, a lacquer or other mass can be applied there before the galvanic bath to prevent galvanic deposition.

[0056] Fig. 4 shows a further variant of a wire mesh layer 2, wherein two separate coating layers 14 and 15 are applied as coating 8 in the lateral second section 12. Here, too, the central area with the first section 11 is formed without a coating.

[0057] Fig. 5 shows a highly schematic plan view of another wire mesh unit 1 according to the invention, which is used as a filter unit 100.

[0058] The wire mesh unit 1 consists of a wire mesh layer 2 comprising warp wires 3 and weft wires 4. A first section 11 is provided in the central area as a filter section 22. Open pores 9 are provided in the meshes 5 of the filter section 22.

[0059] In the holding section 21, which is outer here and surrounds the filter section 22, closed pores 10 are provided, which were closed by the application of the coating 8 and / or by a subsequent post-treatment.

[0060] As a result, the wire mesh layer 2 serves as a filter layer. The filter unit 100 can be attached to the holding section 21, which is sealed. Further sealing is generally not required.

[0061] In Fig. 5, the filter section 22 is shown with two differently shaped pores, namely, on the one hand, with pores 9 in which the corresponding fabric mesh is provided with a surface coating with a thickness of 18, so that the remaining pore size 7 is specifically adjusted. Furthermore, the filter section 22 here has completely uncoated pores 9, whose pore size 7 is correspondingly larger.

[0062] However, it is also possible that no coating 8 or a smaller coating 8 is applied in the area of ​​the filter section 22, so that a correspondingly larger pore size 7 remains.

[0063] The individual wires 3, 4 of the wire mesh layer 2 can be designed as monofilaments. However, it is also possible to use multifilaments 24, as shown in the bottom right of Fig. 5 is indicated by way of example. The entire filter surface or the entire wire mesh layer can consist of multifilament wires.

[0064] Fig. Finally, Figure 6 shows a further variant of a wire mesh unit 1 according to the invention, which consists of two wire mesh layers 2. The two wire mesh layers are connected to each other via the coating 8. This creates a layer composite 20. In the central area, a filter section 22 is again provided, which is surrounded by a holding section 21 towards the edge.

[0065] Overall, the present invention provides a flexibly applicable wire mesh unit 1, which can be used in particular as a filter unit 100. List of reference symbols: 1 wire mesh unit 2 wire mesh layers 3 wire, warp wire 4 wire, weft wire 5 fabric mesh 6 fabric area 7 Pore size 8 Coating 9 pore, open 10 pores, closed 11 first section 12 second section 13 Coating material 14 coating layers 15 coating layers 16 Recess 17 Material reservoir 18 thickness 19 Surface coating 20 layer composite 21 stopping section 22 Filter section 23 Filter section 24 Multifilament 25 Wire (non-metal) 26 Wire (metal) 100 filter units

Claims

[1] Wire mesh unit (1) with at least one wire mesh layer (2) made of warp wires (3) and weft wires (4), wherein the warp wires (3) and the weft wires (4) form meshes (5) and span a mesh surface (6), characterized by in that a pore size (7) of at least some of the fabric meshes (5) of the wire mesh unit (5) is changed by a coating (8), wherein the pore size (7) is specifically influenced by the coating (8) and is thus set in a defined manner, wherein the coating (8) is selectively formed on the fabric surface (6) and wherein the coating (8) is applied more heavily on at least a first section (11) than on a second section (12). [2] Wire mesh unit according to claim 1, wherein the coating (8) is formed as a galvanic coating. [3] Wire mesh unit (1) according to one of the preceding claims, wherein the coating is applied only in sections to the wire mesh layer (2). [4] Wire mesh unit (1) according to one of the preceding claims, wherein at least some meshes (5) are closed by coating material (13). [5] Wire mesh unit (1) according to one of the preceding claims, wherein the wire mesh unit (2) is compacted in at least one region. [6] Wire mesh unit (1) according to one of the preceding claims, wherein the compacted region is punched, partially pressed or compressed and is provided with the coating (8). [7] Wire mesh unit according to one of the preceding claims, wherein the coating (8) has at least in sections a plurality of coating layers (14, 15). [8] Wire mesh unit (1) according to one of the preceding claims, wherein the wire mesh layer (2) has at least one filter section (22, 23) on the mesh surface (6). [9] Wire mesh unit (1) according to one of the preceding claims, wherein open pores (9) are formed on the filter section (22) and the pores (10) are formed closed on a holding section (21) surrounding the filter section. [10] Wire mesh unit (1) according to one of the preceding claims, wherein at least one recess (16) is provided on the mesh surface (6) for fastening or aligning the wire mesh layer (2). [11] Wire mesh unit (1) according to one of the preceding claims, comprising a solder reservoir (17) provided by the coating (8). [12] Wire mesh unit (1) according to one of the preceding claims, wherein the coating (8) has at least one coating layer (14) which consists at least substantially of catalytic materials and in particular of nickel, chromium, gold, silver, copper, titanium, platinum, palladium or tin. [13] Wire mesh unit (1) according to the preceding claim, wherein a thickness (18) of the coating (8) is between 1 µm and 500 µm. [14] Wire mesh unit (1) according to the preceding claim, wherein at least some wires (26) of the wire mesh layer (2) consist of a metal. [15] Wire mesh unit (1) according to one of the two preceding claims, wherein at least some wires (25) of the wire mesh layer (2) consist of a non-metal and / or have an electrically conductive surface coating (19). [16] Wire mesh unit (1) according to one of the preceding claims, wherein at least two wire mesh layers (2) are connected to form a layer composite (20). [17] Wire mesh unit (1) according to one of the preceding claims, wherein at least some wires consist of monofilaments or multifilaments (24). [18] Filter unit (100) comprising at least one wire mesh unit (1) according to one of the preceding claims.

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