阅读说明：本技术 用于过滤单元的过滤元件 (Filter element for a filter unit ) 是由 T·高格勒 于 2020-03-20 设计创作，主要内容包括：本发明涉及一种用于过滤流体的过滤单元(30)的过滤元件(1),其中为了相对于流体可渗透,所述过滤元件(1)由至少一个结构体(6、7)和支撑体(5)组成,并且具有大量网眼/孔(17)。所述结构体(6、7)和所述支撑体(5)各自借助于3D打印工艺生产,其中所述结构体(6、7)具有重复的三维互连晶格结构(15),并且所述支撑体(5)具有单元结构(10)。所述晶格结构(15)的所述网眼/孔(17)由内部交联且刚性连接的杆元件(16)形成。由所述过滤元件(1)解决的问题是使用3D打印工艺提供具有良好过滤效果和良好深负载能力的新的最佳和鲁棒的过滤结构。本发明用于过滤技术模块化单元/机器单元或电机中的流体。(The invention relates to a filter element (1) of a filter unit (30) for filtering a fluid, wherein the filter element (1) is made up of at least one structure (6, 7) and a support body (5) and has a plurality of meshes/pores (17) in order to be permeable to the fluid. The structures (6, 7) and the support (5) are each produced by means of a 3D printing process, wherein the structures (6, 7) have a repeating three-dimensional interconnected lattice structure (15) and the support (5) has a unit structure (10). The meshes/holes (17) of the lattice structure (15) are formed by internally cross-linked and rigidly connected rod elements (16). The problem solved by the filter element (1) is to provide a new optimal and robust filter structure with good filtering effect and good deep loading capability using a 3D printing process. The invention is used for filtering fluids in technical modular units/machine units or electrical machines.)

1. A filter element (1) for a filter unit (30) for filtering a fluid,

-wherein the filter element (1) has a filter element body (3) through which a fluid can flow, the filter element body having at least one structure (6, 7) and a support body (5),

-wherein each structure (6, 7) has a filtering structure permeable with respect to the fluid, the filtering structure having a plurality of meshes/pores (17),

-wherein the filter structure is built up as a three-dimensionally interconnected lattice structure (15) and the three-dimensionally interconnected lattice structure (15) has a repeating regularity,

-wherein the meshes/holes (17) are formed as a clear space by lattice bars (16) firmly connected to each other,

-wherein the support body (5) has a support structure permeable to the fluid,

-wherein said respective structure (6, 7) and said support (5) are both produced by means of a 3D printing method.

2. Filter element (1) according to claim 1,

it is characterized in that the preparation method is characterized in that,

the individual structures (6, 7) and the support (5) are produced by 3D printing of various materials and/or material components.

3. Filter element (1) according to claim 1 or 2,

it is characterized in that the preparation method is characterized in that,

each structure (6, 7) and support (5) is formed by 3D printing of plastic and/or plastic material.

4. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the structure of the support body (5) has a cell structure (10) with channels (12) formed by cells,

-the meshes/holes (17) of the individual structures (6, 7) are smaller than the cells or channels (12) of the support (5).

5. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the structure of the support body (5) has a cell structure (10) with channels (12) formed by cells,

-the lattice rods (16) of the lattice structure (15) of the respective structure (6, 7) have a smaller cross section than the unit rods of the unit structure of the support body (5).

6. Filter element (1) according to claim 4 or 5,

it is characterized in that the preparation method is characterized in that,

the cells or channels (12) of the support (5) are at least two or five or ten times larger than the meshes/holes (17) of the respective structures (6, 7).

7. Filter element (1) according to one of the claims 4 to 6,

it is characterized in that the preparation method is characterized in that,

the cross-section of the unit rods of the unit structure of the support (5) is at least two or five or ten times larger than the cross-section of the lattice rods (16) of the lattice structure (15) of the respective structure (6, 7).

8. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the structure of the support body (5) has a cell structure (10) with channels (12) formed by cells,

-a portion of the lattice rods (16) of the lattice structure (15) penetrates into or through the channels (12) of the unit structure (10).

9. Filter element (1) according to claim 8,

it is characterized in that the preparation method is characterized in that,

a part of the lattice rods (16) of the lattice structure (15) penetrates into or through the channels (12) of the unit structure (10) in such a way that the lattice structure (15) is positively fastened on the unit structure (10).

10. A filter element according to any one of claims 4 to 9,

it is characterized in that the preparation method is characterized in that,

only one individual structural body (6, 7) is provided, wherein the cell structure of the support body (5) is arranged within the lattice structure (15) of this structural body (6, 7), wherein a small number of the lattice rods (16) penetrate the cells.

11. A filter element according to any one of claims 4 to 9,

it is characterized in that the preparation method is characterized in that,

-providing two structures (6, 7) arranged coaxially inside and outside, and the support body (5) being arranged between the two structures (6, 7),

-a small number of said lattice rods (16) penetrating said cells of said unit structure (10) of said support (5) and connecting said two structures (6, 7) to each other.

12. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

-said respective structures (6, 7) and said support body (5) are of hollow cylindrical configuration and are arranged coaxially inside and outside, preferably concentrically to each other,

-the individual structures (6, 7) and the support body (5) are arranged at least substantially parallel to each other.

13. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

-said respective structure (6, 7) is firmly connected to said support body (5),

-the firm connection between the respective structure (6, 7) and the support body (5) is formed by a material-bonded connection.

14. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

-a further structural body (6, 7) is provided on the two structural bodies (6, 7) arranged coaxially inside and outside,

-an inner region (19) of a further structure (6) is in direct contact with and firmly connected to an outer region (18) of the structure (7),

-an outer region (18) of a further structure (7) is in direct contact with and firmly connected to an inner region (19) of the structure (7).

15. Filter element (1) according to claim 14,

it is characterized in that the preparation method is characterized in that,

the structures (6, 7) penetrate each other in an overlapping manner at least in certain regions on the outer region (18) and the inner region (19) thereof.

16. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the size and number of lattice rods (16) of the lattice structure (15) changes abruptly or continuously along and/or transverse to the central axis (2) of the structures (6, 7).

17. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

the material composition of the lattice rods (16) of the lattice structure (15) changes abruptly or continuously along or transverse to the central axis (2) of the structures (6, 7).

18. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

-the material/substance reacting or catalyzing the fluid is embedded inside the meshes/holes (17) formed by the interconnected and firmly connected lattice rods (16),

the fluid to be filtered has a coalescing effect to form particles capable of settling.

19. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

-the meshes/holes (17) of the support (5) formed by the connected lattice rods (16) each have an edge length of 0.05 to 15mm, preferably 0.1 to 10mm, for filtering liquid fluids, or

-said meshes/holes (17) of said support (5) formed by said connected lattice rods (16) each have an edge length of 0.1 to 40mm, preferably 4 to 20mm, for filtering gaseous fluids.

20. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

-a plurality of adjacent structures (6, 7) having mutually different interconnected lattice structures (15),

-a plurality of adjacent structures (6, 7) having mutually different material properties of an interconnected lattice structure (15),

-the mutually different material properties of the mutually different interconnected lattice structures (15) and the interconnected lattice structures (15) being different from each other are abruptly or continuously changed.

21. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

each structure (6, 7) and the support body (5) are made of one piece.

22. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

-a flow guiding element/guide body (28) is built on the structure (6, 7) and the support body (5) and/or inside the structure (6, 7) and the support body (5),

-the flow guiding element/guide body (28) is built in an overlapping manner on a further structure (6, 7) and/or on the support body (5),

-the flow guiding element/guide body (28) has a planar and/or curved and/or wound shape,

-the flow guiding element/guide body (28) changes abruptly or continuously in its shape.

23. Filter element (1) according to one of the preceding claims,

it is characterized in that the preparation method is characterized in that,

-the filter element (1) is designed as a ring filter element (40), wherein the individual structures (6, 7) and the support body (5) form a ring-shaped ring filter body (41) or at least one ring-shaped part of a ring filter body,

-the filter element (1) additionally has two end plates (42, 43) which are arranged at the axial ends of the annular filter body (41), respectively.

24. A ring filter element (40) of a filter unit (30) for filtering a fluid,

-having an annular ring-filter body (41) having or being formed by a filter element (1) according to any one of the preceding claims,

-having two end plates (42, 43) arranged respectively at axial ends of the annular filter body (41).

25. A filter unit (30) having a housing (31) and having a filter element (1) according to one or more of the preceding claims, which is inserted into the housing (31).

Technical Field

The invention relates to a filter element for a filter unit for filtering a fluid.

Background

The filter element is used in a corresponding filter unit for filtering solid particles from a liquid, said filter element having a filter body with a filter material for particle filtration. These filter materials have a filter structure made of a suitable material. For example, filter structures made of woven fabrics and/or cellulose materials are used, which have limited filtering properties and can only be made in complex shapes to a limited extent, due to the material. Filter elements of this type have predetermined and unchangeable filter properties, which allow optimization of the fluid to be filtered only to a limited extent.

DE 4344805C 2 discloses a filter material for adsorption filtration, which has a filter structure composed of particles and formed from a three-dimensional framework of composite fibers. In addition to the structural components, these composite fibers also have first components which have a melting point which is about 20 ℃ lower than the structural components, so that in the case of a corresponding heat treatment the first components can melt and therefore the intersecting or contacting structural components can be connected to one another.

A ceramic filter element for filtering molten metal is known from DE 202017104240U 1. The filter element has a 3D-printed uniform flat structure for filtering molten metal and a 3D-printed uniform support which circumferentially surrounds the structure in a closed manner and thus actually forms a cage for holding the structure.

The fibrous three-dimensional framework consists of structural fibres of various sizes, in particular different fibre thicknesses, which all have the properties of the other first component mentioned above and are connected to each other by the mentioned heat treatment. The fibrous three-dimensional framework of composite fibres is therefore composed of structural fibres of different sizes, more or less freely arranged and connected with respect to each other, but without any uniform repeating structure. Here, thicker structural fibers act as a support effect for the filter structure, wherein thinner structural fibers have a practically important filter function. In this case, the thicker and thinner structural fibers may be composed of the same material. To produce such a filter structure, the finer structural fibers are dispersed into a frame made of coarser structural fibers, for example by hydroentanglement or air entanglement. Alternatively, a finer woven fabric may be formed from thermoplastic structural fibers, such that the woven fabric is subsequently combined with coarser structural fibers to achieve stability of the filter.

Furthermore, cavities are created by the connected structural fibres, in which functional particles for achieving the sorption effect are trapped, and which are themselves formed by the thermoplastic composite fibres and the second low-melting component. Thus, during the thermal joining of the structural fibres, owing to the different melted components, not only irregular and free joining of the structural fibres but also functional deposits are produced in the cavities. Very coarse fibrous frameworks are produced in this way, like long-chain molecules, like inorganic woven fabrics. To achieve a particular effect, the structural fibers may consist of crimped fibers, which may be processed in a manner similar to that described above. Such a fiber structure may have a higher density, but also a higher internal mobility and thus influence the deformability of the frame. The functional particles produced during the heat treatment may for example consist of activated carbon, wherein also other functional particles may be produced and embedded, like for example silica, zeolite clay, alumina, etc.

WO 2015/069619 a1 describes a method of printing a tissue construct with embedded vasculature. Here, the tissue construct produced by means of the 3D printing method comprises one or more tissue patterns, wherein each tissue pattern comprises a plurality of cells of one or more predetermined cell types. The network of vascular channels penetrates one or other tissue patterns, wherein these channels can be introduced into the filaments used therein, even during the production method of printing.

The extracellular matrix component at least partially surrounds the one or more tissue patterns and the network of vascular channels. In the 3D printing method used here, as regards the material, the same as well as different filaments can be used, wherein these filaments can be mixed during the 3D printing process when special nozzles are used. In addition, a filler material such as a hardener, an adhesive, or the like may be added here. To some extent, the particular filler material has been introduced and stored as a homogeneous mixture or as a continuously usable mixture within the filament.

Disclosure of Invention

The present invention relates to the problem of providing an improved embodiment of a filter element for particle filtration, which is distinguished in particular by a high robustness and a high filtration effect and by a high depth loading capacity with satisfactory stability.

According to the invention, this problem is solved by means of the subject matter of the independent claims. Advantageous embodiments are the subject matter of the dependent claims.

According to the invention, a filter structure of a lattice structure interconnected by three dimensions is used for this purpose, which is preferably produced completely by a 3D printing method. In such 3D printing methods, the filaments are melted and applied layer by nozzles onto a support or are stacked along a support mass, wherein the printed filter element may consist of various filaments and various filament materials. Here, the filament may be, for example, a thread-like annular material with specific additives, wherein instead of a thread-like filament also powder, granular or liquid materials may be used for the treatment in the printing nozzle. This 3D printing method may also create complex shapes for the filter element, wherein undercut shapes as well as other shapes are also possible. Also, this filter element can have very complex shapes engaging each other, which means that the available installation space of the filter element is used to the maximum.

Furthermore, the design of the filter unit can thus be carried out with optimum utilization of the installation space available for the filter unit, and geometric designs of filter units which have hitherto not been producible can be realized.

According to the invention, the support body is printed by means of such a 3D printing method as a support or support frame, which supports one or more structures, which serve as the actual filter and thus impart dimensional stability to the entire filter element. At least one structure may contact the support body on the outside and on the inside of this support body, wherein the structure may be designed filament-like and less dimensionally stable than the support body, the structure being kept stable in its position and shape by the support body due to the contact with the support body.

Here, the structure and the support body can expediently both be produced adhesively from one piece, wherein it is also possible to make the design from separate parts for later construction. Here, the structural body has a three-dimensionally interconnected lattice structure composed of regularly repeating arranged rod elements. In this case, the rod elements are arranged at predetermined three-dimensional angles, so that a lattice structure is produced and a three-dimensionally repeating clear space, the so-called mesh/hole, is likewise formed. These meshes/holes may have an edge length of 0.05mm to 15mm, in particular 0.1mm to 10mm, which is specific for filtering liquid fluids, wherein the actual edge length and thus the dimensions of the meshes and holes determined are optimally adapted to the fluid to be filtered. Here, the throughflow rate of the fluid and the resultant pressure difference from the fluid entering the filter element to the fluid flowing out have specific values, so that the filter effect is maximized and the possible heating of the throughflowing fluid remains low. The edge length of the mesh/hole is preferably designed to be in the range of 0.1mm to 40mm, in particular 4mm to 20mm, during the filtration of the gaseous fluid. Due to the selection of mesh and pore sizes suitable for the fluid to be filtered, filter elements produced by means of 3D printing methods can have a filter area which is doubled compared to currently commonly used filter inserts.

The filaments used in the process of 3D printing the structure may contain filler materials such as stabilizers, binders or catalytically active materials embedded in the filaments during creation of the lattice structure. In these special embedded materials, during printing of the bar elements, the catalytically active material may for example be deposited such that it is gathered in the clear space of the mesh/pores and is able to perform their specific catalytic function when in contact with the fluid to be filtered. Of course, other suitable methods, such as, for example, melting certain materials or others may be used to introduce these materials into the mesh/holes.

Here, the fluid to be filtered often exhibits a coalescing effect (hydrophobic/oleophobic) in which the fluid fractions and/or particles to be precipitated/filtered are brought together as contaminant fractions and shaped into larger particles/droplets, which are then precipitated out by the actual filtering effect of the filter element.

An embodiment is particularly advantageous in which the individual structures and the support are 3D printed from various materials and/or various material components. Thus, the material may be adapted to the different functions of the two components in order to enhance the respective functions.

Each structure and support may conveniently be 3D printed from plastics and/or plastics material. In this case, a particularly fine structure can be achieved. In addition, the filter element is therefore relatively inexpensive.

An embodiment is advantageous in which the structure of the support has or is formed by a cell structure, wherein this cell structure has channels formed by cells. In other words, the cell is constructed to be open or permeable. In addition, it is preferable to define the cells or channels of each structure to have a mesh/hole smaller than that of the support. Thus, the functions of the structure and the support are improved. Smaller meshes/holes improve the filtration effect. Larger cells increase stability, particularly if accompanied by an increase in the thickness of the lattice rods involved. It can therefore be provided in particular that the cell rods used for building the cell structure have a larger cross section than the lattice rods used for building the lattice structure.

According to a further aspect, the cells or channels of the support are at least two or five or ten times larger than the cells/pores of the respective structures. Additionally or alternatively, the cell rods of the cell structure may have a transverse cross-section two or five or ten times larger than the lattice rods of the lattice structure. Therefore, the functions of the structure and the support can be improved.

An embodiment is particularly advantageous in which the structure of the support has a cell structure with channels formed by the cells, wherein a part of the lattice rods of the lattice structure penetrates into or through the channels of the cell structure. Thus, the lattice structure and the elements of the unit structure interact. On the one hand, this makes the design very compact, since the structure and the support body penetrate more or less into each other. On the other hand, a certain fixing of the structure on the support body can thus be achieved, which improves its supporting effect.

According to a further development, provision can be made for a portion of the lattice rods of the lattice structure to penetrate into or through the channels of the cell structure, so that the lattice structure is fixed to the cell structure in a form-fitting manner (formschlussig). In this case, provision can be made in particular for the lattice bars not to touch or to touch the cell structure only loosely. Thus, the lattice rods remain movable relative to the cell structure. Alternatively, depending on the printing method, there may also be a material-bonded connection, in particular a fusion, at the contact points. Due to the form fit, the individual structures can be easily stabilized by the support.

As previously mentioned, coaxially concentrically arranged structures having a lattice structure may for example be used outside and/or inside the support. To increase the dimensional stability of the structures, during the 3D printing method, these structures may be connected to the support and to other structures by means of an adhesive contained in the filaments or an additionally supplied adhesive. In addition, the 3D printing method provides the possibility of placing the connecting rod elements relative to each other between the support body and the structure or between the individual structures such that these rod elements penetrate the structure at least to a certain extent. Thereby, a particularly high strength and connection of the bodies to each other is achieved. These connecting rod elements may consist of the same material as the structural body or the support body, wherein for increasing the strength the connecting rod elements preferably consist of a suitable material with a higher strength. Additionally, these tie-bar elements may have a shape, thickness, and/or geometric connection structure for the structure that is different from the lattice structure of the structure. Thus, one or more structures may be arranged at an outer region of the support body, wherein the connecting rod elements run inside the structures and on the outer region of the structures.

Another embodiment according to the invention may consist in a three-dimensionally interconnected lattice structure with abrupt or continuous transitions of lattice structures of different sizes, and thus permeability and filtering function may be changed or modified. This occurs, for example, as a function of the flow and/or the distribution of the particle sizes to be filtered, which results in a considerable increase in the efficiency of the filter element. With the same change in behavior, the material of the interconnected lattice structure may also change abruptly and/or continuously. These previously described possibilities of variation relate not only to a specific distribution of the lattice structure and materials of the structures, but may also occur in the case of adjacent structures, so that a plurality of outer and/or inner structures arranged around the support may have a plurality of variations of the lattice structure and materials. All these changes can of course take place abruptly, in a continuous flow, or in segments.

For all these variations, it is likewise possible for a fluid-connecting transition with a modified lattice structure and/or material to occur relative to its contact region in the case of adjacent structures arranged, for example, substantially parallel or coaxially concentrically. Thus, for example, the inner region of the structure arranged on the outside is in direct contact with the outer region of the structure arranged on the inside. The aforementioned joining of the two structures can take place in this region. Similarly, the same is true for structures arranged in the inner region of the support. In addition, the inner and outer structures including the aforementioned variations may be realized as an integral part together with the support body.

The support body assumes the supporting function of the entire filter element and is therefore designed to be particularly stable. For this reason, during the 3D printing method of the support, higher strength filaments may be used. Furthermore, this support function is adapted by the geometric design of the stronger dimensions, in particular by the dimensions and shape of the cell structure support. Thus, according to the invention, during the forming of the support body, it is possible to use, for example, a shape like a polygonal cell structure, preferably a hexagonal honeycomb structure with considerably increased wall strength. The lattice structures used may have a considerable static load caused by their size and their mesh density, which in the case of a plurality of parallel adjacent lattice structures cannot be supported by themselves and their interaction. The requirements on the support body will therefore be defined according to the load and, in addition, be adapted to the forces of the circulating fluid, which will take place by means of the shape and dimensions of the support body and its geometry. For this purpose, the support and the structure may already be connected together and printed together. The separately printed support and structure are subsequently joined together and in this case, for example, bonded together, possibly as another production method.

According to the invention, a flow guiding element, a so-called guide body or baffle, can be used as another design. The 3D printing method used in the production of the support and the structure enables first of all this type of guide bodies in any desired number and shape in the outer region of the structure and in the interior of the structure. Here, the guide body can have a wide range of geometries, wherein, however, these geometries always fulfill the task of diverting the fluid in the direction of the fluid flow in a targeted manner. A guide body of this type can therefore be used in a shovel-shaped manner, in a stepped manner or as a winding surface, wherein a cuboid-shaped design is also conceivable for generating a flow resistance for a rotating fluid or for changing the dynamic pressure. Here, the guide may be arranged inside the lattice structure of the structure body such that the rod elements of the lattice structure may penetrate the guide in any desired three-dimensional arrangement and number. In addition, in the case of printing the structural bodies and/or the support body in common, these guide bodies may be arranged and implemented to overlap through a plurality of structural bodies. Due to this overlapping connection of the structures/supports, an additional reinforcement of the entire printed filter unit is achieved. In this way, the regions of the filter element which hitherto have an unfavorable throughflow and limited filter effect can also be used optimally for filtering fluids. A considerable increase in filtration efficiency is also exhibited for the same size of filter element. Furthermore, due to the use of the guide body, it is also possible to supply the fluid to a predetermined region of the filter element with a particularly suitable filtering effect in the case of corresponding contamination, due to the targeted diversion of the fluid. In the case of a corresponding arrangement of the guide bodies in the supply region of the filter element, that is to say upstream of the inflow of the fluid into the structure, the guide bodies can generate a cyclone effect, in which case the fluid circulates swirls upstream of the structure. As a result of this effect, coarser and heavier contaminant particles collect on the housing wall, so that these particles cannot even penetrate into the filter. These coarser contaminant particles are guided along the housing wall to a suitable collection point where they can also be removed. This pre-classification of the potentially coarser contaminant particles results in a significantly longer operating time of the filter element. In this way, the fluid can thus be diverted in a targeted manner through a plurality of sections/regions of the filter and thus be optimally filtered.

According to an advantageous application, the filter element can be designed as a ring filter element, wherein the individual structures and the support form a ring-shaped ring filter body or at least a ring-shaped part thereof, wherein the filter element or the ring filter element additionally has two end plates which are arranged in each case at an axial end of the ring filter body.

In other words, the ring filter element according to the invention has an annular ring filter body which is formed at least partially by a filter element of the aforementioned type. The individual structures and supports are thus of annular, in particular cylindrical, configuration. In addition, the ring filter elements each have an end plate at an axial end of the ring filter body. Preferably, the ring filter body consists only of filter elements of annular configuration, since for certain applications the ring filter element body has sufficient stability due to the support structure, in which applications, for example, low to moderate pressure differences occur between the original side and the clean side. In other applications, for example in which a high pressure difference occurs between the original side and the cleaning side, the ring filter body can additionally be equipped with an inner and/or outer frame on which the ring filter elements or their ring filter element bodies are radially supported.

In this case, at least one of the end plates may conveniently be configured as an open end plate and have a central passage opening. Depending on the type of application of the ring filter element, the other end plate can likewise be designed as an open end plate or as a closed end plate, which axially closes the interior closed by the ring filter body. By means of 3D printing, the end plate can be conveniently printed onto the annular filter body. In this case, the end plates can consist of a different material, in particular of a different plastic than the individual structures and the support body. Furthermore, it is conceivable to produce the end plates and the support body from the same material.

A design according to the invention is considered as a further alternative to the function of a single structure. Here, for example, the outermost and/or innermost structures can no longer be constructed as lattice structures, but are printed as solid bodies and thus constitute the geometric boundary of the filter unit itself as a housing wall. Due to the higher strength requirements placed on the housing, suitable materials can be used as filaments in the case of common structures and housings or separately printed housings. Also, it is conceivable that in order to achieve such higher strength, a specific material is additionally supplied to the filaments at the time of printing in the 3D printing process.

Within this housing wall, the filter element can be designed in a conventional, previously described arrangement, wherein there can be a fixed connection between the lattice structure of the inner structure and the interior of the printed housing wall. Of course, the housing wall can be realized and printed separately from the inner adjacent structure, wherein the actual filter element then has to be introduced into the housing and fixed there. This can take place, for example, by means of limit stops serving as insertion limits, up to which the filter element is pushed in and is then firmly connected in a positionally fixed manner to the housing by suitable methods, for example, thermal fusion or adhesive bonding. Of course, fastening methods which can be separated again, such as, for example, a screw connection, a clamping ring, a clamp or others, can also be used.

A housing printed in this way and equipped with a filter element can have a limiting element in the form of a fastening flange for producing a complete filter unit. In the case of these fastening flanges, fastening holes and access openings are also introduced, for example at the same time during printing. In order to be able to replace the filter element here as well, it is conceivable for the fastening flange to be connected to the housing in a detachable manner. Thus, the filter element introduced in a removable manner can be replaced, while the housing can be reused. Of course, it is also possible to completely replace the filter unit.

In the case of replaceable removable filter units, 3D printed components and contemporary components produced in a standard manner may be used in combination.

Further important features and advantages of the invention are obtained from the dependent claims, the figures and the associated description of the figures based on the figures.

It is to be understood that the features mentioned above and those yet to be explained below can be used not only in the respectively specified combination but also in other combinations or alone without departing from the scope of the present invention.

Drawings

Preferred exemplary embodiments of the invention are shown in the drawings and are explained in more detail in the following description, wherein identical reference numerals indicate identical or similar or functionally identical components.

In the drawings, there are shown schematically:

figure 1 shows a hollow cylindrical filter element constructed from a support body and a structure,

figure 2 shows a hollow cylindrical support body having a cell structure,

figure 3 shows a hollow cylindrical structure with a three-dimensional interconnected lattice structure made of rod elements,

fig. 4 shows a hollow cylindrical filter element constructed from a support body and a structure, with sections of different lattice structures,

fig. 5 shows a hollow cylindrical filter element built up from a support body and a structure body, with flow guide elements/guides arranged inside and outside the lattice structure,

fig. 6 shows a 3D printed filter unit consisting of a housing, a flange and a filter element.

Detailed Description

Fig. 1 shows a cylindrical filter element 1, the filter element body 3 of which is composed of a support body 5 and structural bodies 6, 7. In the case of the filter element 1, corresponding coaxial and concentrically positioned hollow cylindrical structures 6, 7 are arranged on the inner region 14 and the outer region 13 of the support body 5. Through-flow 8 of the fluid through filter element 1 takes place here, for example from the outside of hollow-cylindrical filter element 1 into the inner region of hollow-cylindrical filter element 1, whereby the fluid is then guided further substantially parallel to central axis 2. Of course, any desired geometric configuration of filter element 1 having structures 6 and support body 5 may be used instead of hollow cylindrical filter element 1. Here, flat and/or cubic filter elements 1 are preferably used.

The outer structure 6 is built up as a three-dimensionally interconnected lattice structure 15 and is produced by means of a 3D printing method and is aligned substantially parallel to the support 5. The inner region 19 of the outer structure 6 is in direct contact with the outer region 13 of the support body 5 in certain regions and is firmly connected to the support body 5 in this contact region. This connection can take place by means of an adhesive bonding of the contact regions or by means of a material connection method of the contact regions. Another possibility for connecting the two bodies 5, 6, which is not shown in the drawing, consists in a three-dimensionally interconnected lattice structure 15, which is composed of rod elements 16, is joined by means of the structure of the support body 5 using the rod elements 16, and in this way the connection of the two bodies 5, 6 is produced.

Since the inner region 19 of the outer structure 6 is in contact with the outer region 13 of the support 5, similar considerations apply to the outer region 18 of the lattice structure 15 of the inner structure 7 and the inner region 14 of the support 5, which are in contact at least in some regions. Likewise, it is possible that the bar elements 16 are connected to the two bodies 5, 7 by three-dimensional interconnection of the cell structures 10 of the support body 5, wherein the cell structures 10 have a three-dimensional honeycomb structure 11, but can also have any type of other shape.

In fig. 2, the interconnection and the mutual dimensionally stable connection of the two bodies 6, 7 takes place by the rod elements 16 of the lattice structure 15 by the joining of the cells of the cell structure 10 of the support body 5, wherein the joining at the support body 5 takes place by the spaces of the cell structure 10 or by the walls of the cell structure 10. Since the support body 5 has to hold and support the plurality of lattice structures 15, for example, as a support body, and in addition has to absorb also the force due to the flowing fluid, the support body 5 is realized in a very stable shape. In the example shown, the support body 5 has a honeycomb structure, i.e. a cell structure 10, which has the greater material strength and wall strength 11 of the honeycomb structure 10 for the purpose of supporting forces. This means that the rod-shaped unit rods of the unit structure 10 have a larger cross section than the lattice rods 16 of the lattice structure 15. It is also possible to use filament materials with higher strength when printing the support body 5 and/or to introduce specific strength-enhancing material components into the melt of the filaments during the 3D printing of the cell structure 10. The selection of possible cell structures 10, here hexagonal honeycomb structures 10, particularly advantageously supports forces and at the same time creates channels 12 which are large and regular enough for the passage of fluids and rod elements 16 running through these channels 12, which serve as a connection between the support body 5 and the outer structure 6 or as a connection of the inner structure 7 through the support body 5 to the outer structure 6. The bar elements 16 protruding through the passage openings 12 of the support body 5 may travel directly through the passage openings 12 and/or penetrate through the area of the honeycomb structure 10 and are thus firmly connected to the honeycomb structure. This penetration of the bar elements 16 and the cell structure 10 additionally strengthens the connection.

In fig. 3 hollow cylindrical structures 6, 7 are depicted with a lattice structure 15 which is built up in a three-dimensional interconnected manner by rod elements or lattice rods 16. Here, the rod elements 16 are combined in a plurality of arrangements repeated in this manner and interconnected star-shaped and radially. The hollow cylinders depicted here show such an interconnection structure in terms of their longitudinal length 21 and their width 20, so that three-dimensionally interconnected hollow cylindrical structures 6, 7 are produced.

Due to the three-dimensionally interconnected lattice structure 15, the star-shaped arrangement of the rod elements 16 results in a clear space which is arranged and oriented in the manner of a mesh 17 or holes 17, so that the fluid to be filtered can flow optimally through the structures 6, 7. In this case, contaminants are left in the meshes/holes 17 or at the bar element 16, wherein the structures 6, 7 filled with contaminants ensure a satisfactory throughflow 8 of the structures 6, 7 for a long time due to the large number of meshes/holes 17 without an increased dynamic pressure when the flow 8 through the structures 6, 7 reaches a critical value. On the inner region 14 or the outer region 13 of the structures 6, 7, the lattice structure 15 is provided with an adhesive for connection to other structures 6, 7 arranged coaxially inside and outside, preferably concentrically. For example, during printing, such adhesive may be located in these regions as a filler material for the filaments, wherein subsequent adhesive layers of the inner region 14 and the outer region 13 are also possible. Also during the 3D printing method, substances may be introduced into the lattice structure 15 together with the filaments or as a further supplied material, which substances are collected in a concentrated manner in the meshes/pores 17 in order to produce a specific reaction and/or catalytic effect of the fluid to be filtered there. These are particularly useful for permanently adhering some contaminants to the rod elements 16 and/or for bonding/connecting substances present in the fluid to each other, and thus these may be filtered out as contaminants by the lattice structure 15.

Fig. 4 shows a hollow-cylindrical filter element 1, which is constructed from a support body 5 and structures 6, 7, wherein the structures 6, 7 have a plurality of sections 22, 23, 24 of different lattice structures 15. Here, the structures 6, 7 are arranged coaxially, in particular concentrically inside and outside, with the support body 5 being located between the two structures 6, 7.

The structures 6, 7 can be divided, for example, in terms of their longitudinal length 21 into a plurality of sections, here into three sections 22, 23, 24. In these divisions, the sections 22, 23, 24 are for example composed of different materials and/or the lattice structure 15 differs in the number of rod elements 16 or the number of meshes/holes 17 it implements. Thus, a coarse mesh lattice structure 15 consisting of several rod elements 16 can be depicted in the first section 22, and a section 23 adjoining this section 22 has a finer lattice structure 15 with a plurality of rod elements 16 that are shorter than the rod elements present in the section 22.

Similarly, the subsequent segment sections 24 may have a further, distinctly different lattice structure 15.

Here, the transition between the individual segments 22, 23, 24 and the different lattice structures 15 can take place abruptly or continuously smoothly. As previously mentioned, the division of the structures 6, 7 into a plurality of sections may be further divided into concentrically arranged structures 6, 7 and/or radial sections not depicted here. Here too rough to less rough lattice structures 15 can then occur, and these can of course also have abrupt and/or continuously smooth transitions. In this case, it is immaterial whether the structural bodies 6, 7 are present as individual lattice structures 15 or consist of lattice structures 15 which are connected together and thus of a plurality of structural elements 6, 7 which are connected.

The division into different sections 22, 23, 24 is important for optimal filtration of the fluid, wherein the sections 22, 23, 24 can be independent of each other and differ in size. Thus, for example, the fluid can optimally flow through the areas of the structures 6, 7 through which the fluid flows less intensively due to the change in dynamic pressure by means of the thicker or smaller meshes/holes 17 and fewer or more rod elements 16 and which thus effectively filter the fluid.

Fig. 5 shows a hollow cylindrical filter element 1 built up from a support body 5 and structures 6, 7, wherein the structures 6, 7 are arranged coaxially, preferably concentrically with respect to each other. In the region of the support body 5, a flow-guiding element 28 (referred to as a guide body/baffle 28) is integrated into the lattice structure 15 of the structural bodies 6, 7. During 3D printing, these guides 28 are printed inside or outside the lattice structure 15 of the structures 6, 7.

Such a guide body 28, which is positioned on the edge region of the lattice body 15, can guide the fluid to be filtered in a targeted manner due to its geometry and positioning, or to certain regions of the lattice body 15, so that the aforementioned optimum throughflow 8 and the filtering effect of the filter element 1 are achieved. For example, circular vortexing of the fluid in a cyclonic fashion or manner may constitute one possible effect here. During the throughflow 8 of the structural bodies 6, 7, the targeted diversion of the fluid can also be achieved by means of a guide 28 which is arranged inside the lattice body 15 and is correspondingly shaped. In addition, these internal guides 28 are also introduced or printed directly into the lattice body 15 during the 3D printing of the lattice body.

Furthermore, the guide 28 may also be arranged inside the lattice body 15 and between two or more lattice bodies 15. The fluid flowing into the lattice body 15 can therefore be guided very efficiently and rapidly into further lattice bodies 15 or distributed into said lattice bodies by the guides 28 arranged one above the other. In addition, the fluid can be diverted in alternating directions by a plurality of guide bodies 28 assigned to one another and thus enter different filter regions. For this purpose, the guide body 28 is designed as a curved surface, a winding surface with an increased or reduced dimension, wherein further protruding or recessed moldings may be present on the guide body 28 to support the guiding function of the fluid.

Instead of a flat guide body 28, geometric solid bodies, for example, cube-shaped bodies, can be introduced into the lattice body 15 and the fluid can flow around them as a flow resistance. Here, a vortex is generated which in turn influences the flow behavior of the fluid, so that it is thus diverted in a targeted manner into certain regions of the filter element 1 and into the lattice body 15.

In fig. 6 a 3D printed filter unit 30 with a housing 31, a flange 33 and a filter element 1 is shown. Here, during 3D printing, for example, the outermost structural bodies 6 are not printed as crystal lattices 15, but as entities in the form of housing walls 31. The housing 31 depicted in fig. 6 substantially corresponds to the geometry of the filter element 1 and is therefore firmly constructed. In addition, the housing 31 may be printed simultaneously with the filter element 1 and as an integral component. A fastening flange 33 is moulded at the end of the housing 31, for example for mounting the filter unit 30 on a machine. The flange 33 is realized for this purpose with fastening holes 35 for mounting by means of suitable fastening means and with corresponding access openings 34 for the supply or discharge of fluid. During the 3D printing method, the fastening hole 35 and the access opening 34 are molded correspondingly. In this way, the complete filter unit 30 with the filter element 1, the housing 31 and the fastening flange 33 can be used and replaced as a completely printed design. Here, the housing 31 advantageously consists of a stronger material, which is produced during printing by means of correspondingly adapted filaments. Furthermore, it is conceivable that a corresponding filler material is supplied to the filaments used here to increase the strength.

One possible further embodiment consists in producing the housing 31 as a separate component without the filter element 1 by means of a 3D printing method. In this case, the filter element 1 is later introduced and positioned in the housing 31.

For positioning, the bump stopper 32 or insertion boundary 32 may be molded in or on the housing 31 during 3D printing. The inserted filter element 1 can be fixed in the housing 31, wherein the flange 33 can also serve here as a fastening element from the insertion side. The fastening flange 33 is here again attached to the housing 31, wherein the flange for mounting the filter element 1 is designed to be detachable. Instead of a printed housing 31, the previously produced filter element 1 can of course be pushed into an existing conventional housing 31, wherein instead of the housing 31 also a suitable position in the duct can be used. Thus, for example, such a filter element 1 can be used in almost any desired position in the pipe system of a machine/motor.

This detachable flange 33 is then connected to the housing 31 by means of a suitable connection means, so that it can be detached or fixed again. A particular advantage of such a 3D printed housing 31 of the filter unit 30 is that the housing 31 may deviate from a symmetrical shape in terms of its shape and size, and that complex housings 31 with frequently changing shape transitions may be realized. The filter element 1 used here corresponds accordingly to this housing shape. In particular, in the case of these filter elements 1 having a shape which changes a plurality of times, the guide body 28 depicted in fig. 5 is particularly interesting, so that all important regions of the filter element 1 can flow through efficiently.

In principle, the individual structures 6, 7 and the support body 5 can be 3D printed from various materials and/or material compositions. In this case, each structure 6, 7 and support 5 may be 3D printed from plastic and/or plastic material.

An embodiment is preferred in which the structure of the support body 5 has a cell structure 10 with channels 12 formed by cells. In this case, the battery is formed using the strip-shaped battery bars of the battery structure 10. Preferably, the mesh/pores 17 of each structure 6, 7 are smaller than the cells or channels 12 of the support 5. For example, the cells or channels 12 of the support body 5 may be at least two or five or ten times larger than the cells/pores 17 of the respective structures 6, 7.

Furthermore, it can be provided that the lattice bars 16 of the lattice structure 15 of the individual structural bodies 6, 7 have a smaller cross section than the cell bars of the cell structure 10 of the support body 5. For example, the cross-section of the unit rods of the unit structure 10 of the support body 5 may be at least two or five or ten times larger than the cross-section of the lattice rods 16 of the lattice structure 15 of the respective structural body 6, 7.

As described above, a portion of the lattice rods 16 of the lattice structure 15 penetrate or pass through the channels 12 of the unit structure 10. Preferably, a part of the lattice bars 16 of the lattice structure 15 penetrates into or through the channels 12 of the unit structure 10, so that the lattice structure 15 is fastened to the unit structure 10 in a form-fitting manner. A further fixing by means of a welded connection can then be dispensed with.

According to fig. 7, the filter element 1 can be designed as a ring filter element 40, wherein the individual structures 6, 7 and the support body 5 form a ring-shaped ring filter body 41. In other words, in this case, the filter element body 3 is configured annularly and forms the annular filter body 41. The filter element 1 or the ring filter element 40 additionally has two end plates 42, 43 which are each arranged at an axial end of the ring filter body 41. The upper end plate 42 in fig. 7 is configured as an open end plate and accordingly has a central passage opening 44 which opens out into an interior 45 enclosed by the ring filter body 41. The lower end plate 43 in fig. 7 may likewise be configured as an open end plate. Alternatively, the lower end plate 43 may also be configured as a closed end plate that axially closes the interior 45. By means of 3D printing, at least one of the end plates 42, 43 may be printed onto the ring filter body 41.

Fig. 7 therefore shows a ring filter element 40, in particular a filter unit 30 for filtering a fluid, wherein the ring filter element 40 is equipped with an annular ring filter body 41 formed by a filter element 1 of the aforementioned type, and two end plates 42, 43 which are each arranged at an axial end of the ring filter body 41. During operation of the ring filter element 40, it flows radially through the ring filter body 41. Depending on the direction of the throughflow, cleaned fluid can be discharged or uncleaned fluid can be supplied through the throughflow opening 44. The axial direction of the ring filter element 40 is defined by its central longitudinal axis 46.