Filter element, filter element holder for a filter element, filter device and method for manufacturing a filter element

Abstract

The invention relates to a filter element (2) having a flow-through porous filter body (4) extending between a head end and a longitudinally opposite bottom end; wherein a head structure (6) is formed at the head end of the filter element (2), the head structure (6) having at least one abutment surface seal (10) configured to seal the filter element (2) against a filter element holder (26), wherein the head structure (6) has a substantially longitudinally extending side wall (8), and the abutment surface seal (10) is formed on the substantially longitudinally extending side wall (8) of the head structure (6) of the filter element (2).

Description

TECHNICAL FIELD

[0001] The present invention relates to a filter element, a filter element holder for a filter element, a filter device, and a method for producing a filter element. BACKGROUND

[0002] Such filter elements are used in industry in factories and plants in many branches of industry, for example in the automotive industry, the chemical industry, the food industry or for the production of building materials.

[0003] The filter element is porous to allow a flow therethrough and has an inherent stability, i.e. the through-flow porous, inherently stable filter element of the type according to the invention can have a filter body made of polyethylene particles sintered together or a more heat-resistant plastic such as polyphenylene sulfide or the like for use at higher temperatures.

[0004] The filter element has a filter body on which a filter head is formed. The filter head serves to secure the filter element in the filter device. The filter head must ensure sealing and retention in the filter device. For this reason, in the known filter elements, the filter head is produced as a separate component and is connected to the filter body, for example by molding the filter head to the filter body. Furthermore, the filter head is further reinforced by a metal insert. Due to the complex construction of the filter head resulting, the manufacturing process of the filter elements known to date has been difficult to automate. SUMMARY

[0005] It is therefore an object of the present invention to provide a filter element which is easier to manufacture, in particular in a manufacturing process which allows easier automation.

[0006] The filter element according to the invention comprises a through-flow porous filter body extending between a head end and a longitudinally opposite bottom end. At the head end of the filter body, a head structure is formed which cooperates with a filter element holder of a filter device, the head structure having at least one sealing portion which is adapted to seal the filter element with respect to the filter element holder. The head structure has a substantially longitudinally extending side wall, and the sealing portion is formed on the substantially longitudinally extending side wall of the head structure of the filter element.

[0007] Furthermore, the invention relates to a filter element holder for receiving a filter element according to the invention, the filter element holder comprising a support plate having at least one filter element receptacle into which a filter element according to the invention can be inserted such that the filter element is seated in the filter element receptacle with its head structure.

[0008] Another aspect of the invention relates to a combination of a filter element according to the invention and a filter element holder according to the invention. In this arrangement, the filter element can be inserted into the filter element holder such that, in the inserted state, the filter element separates the original fluid space of the filtration device from the clean fluid space. The sidewalls of the head structure include a sealing portion that mates with the filter element container to seal the filter element relative to the filter element holder, particularly with a sealing element extending transversely to the longitudinal direction.

[0009] The present invention also relates to a filtration device comprising a primary fluid space, a clean fluid space, and a combination of a filter element and a filter element holder according to the invention. The filter element is inserted into a filter element container formed in the filter element holder, such that the filter element in the inserted state separates the primary fluid space from the clean fluid space.

[0010] An additional aspect of the invention relates to a method of manufacturing a filter element according to the invention. The method includes manufacturing a flow-through porous and inherently stable filter body, and forming a head structure on the filter body, wherein the head structure is provided with at least one sealing portion, the at least one sealing portion being configured to cooperate with a filter element retainer of the filter device to seal the clean fluid space of the filter device from the original fluid space. Specifically, the sealing portion is formed on a longitudinally extending sidewall of the head structure. The manufacturing of the filter element can be automated.

[0011] The filter element according to the invention is easier to manufacture than known filter elements. In particular, fully automated manufacturing of the filter element is feasible because the head structure does not require any special reinforcements. In particular, if desired, the head structure can be made of the same material as the filter body even in the same manufacturing process.

[0012] The filter element is specifically designed to be mounted on a filter element holder of the filtration device. The filter element holder, together with the filter element mounted therein, separates the clean fluid side of the filtration device from the raw fluid side. In the installed state, the filter element is fixed to and supported by the filter element holder. The arrangement of the seal on the longitudinally extending sidewall of the head structure according to the invention allows for a configuration in which the seal, in the installed state, only causes a sufficiently fluid-impermeable seal by engaging with a reverse sealing structure on the filter element holder. However, it is no longer necessary for the interaction between the seal and the reverse sealing structure to also provide retention or attachment of the filter element to the filter element holder, or substantially support such retention or attachment. Instead, the filter element according to the invention can be configured such that the function of securely fastening and supporting the filter element in the filter element holder is provided by other parts or structures on the head structure besides the seal. This design allows the head structure to be made entirely of a single material, particularly a plastic material. Specifically, the head structure can now be made of the same plastic material as the filter body. There is no longer a need to provide additional reinforcing elements or reinforcement structures in the head structure, because the function of providing a seal and retention / fastening for the filter element in the filter element holder is performed by different parts of the head structure.

[0013] For example, the filter element, including the head structure, can be entirely manufactured in the sintering process that manufactures the filter body. It is only necessary to ensure that the sidewalls of the head structure, extending in the longitudinal direction, are formed during the sintering process and that these sidewalls are provided with a sealing portion. This can be done during the sintering of the filter body (e.g., by appropriately constructing the area of ​​the sidewalls that forms the sealing adjacent surface), or it can be done after sintering (e.g., by providing a separate sealing element that mates with the sidewalls).

[0014] The filter element is inherently stable; that is, the filter body itself possesses sufficient rigidity to allow the filter element to be erected. Therefore, in principle, no additional support structure is required to erect the filter element within the filtration device. The filter body of the filter element is flow-through porous and allows (possibly with the aid of an additional surface coating) filtration of the raw fluid, which carries foreign matter and / or foreign particles as it passes through the filter element. These foreign substances remain on the raw fluid side of the flow-through porous filter body. A cleaning device can be used to remove these foreign substances from the filter body. For example, for this purpose, a cleaning device operating according to the principle of compressed air pulses can be provided, which applies pulses of compressed air to the filter element, particularly according to the countercurrent principle, in the direction opposite to the flow direction of the clean fluid exiting the filter element from its clean fluid side.

[0015] When a filter element is installed in a filter device, the head end of the filter element specifically refers to the end of the filter element closest to the filter element holder. This head structure ensures that the filter element is securely fastened in the filter element holder and also provides a good seal between the clean fluid side and the raw fluid side of the filter device when the filter element is installed.

[0016] The surface / wall of the filter element extending in the longitudinal direction extends parallel to the direction in which the filter element is inserted into or removed from the filter element holder. The statement "the surface / wall extends substantially in the longitudinal direction" is intended to express that the surface / wall does not need to be precisely parallel to the longitudinal direction, but can also extend at an acute angle to the longitudinal direction, such as an angle of up to 15 degrees. For example, the longitudinal direction can be the axis of a truncated pyramid or truncated cone, wherein the side surfaces formed on the head structure lie on the side surfaces of the truncated pyramid or truncated cone.

[0017] When the filter element is inserted into the filter element holder, the seal can indeed engage with the reverse sealing structure of the filter element holder through friction and / or reliably, providing sufficient sealing to prevent the passage of the original fluid to the clean fluid side or vice versa. This means that a certain preload is transmitted via the seal to create a tight fit between the seal on the head structure of the filter element and the reverse sealing structure on the mating filter element holder. Conversely, through the engagement of the seal and the reverse sealing structure, no force (at least not a significant force) needs to be transmitted to hold, secure, and / or support the filter element in the filter element holder, particularly to prevent longitudinal displacement of the filter element. In particular, the seal and the reverse sealing structure should even mitigate the transmission of such force. To prevent longitudinal displacement of the filter element, additional areas of the head structure can be provided, or the head structure can have other holding arrangements.

[0018] In its simplest form, the sealing portion on the head structure can have an abutment surface formed on the outer surface of the sidewall, which, upon installation, seals against a corresponding mating abutment surface of the filter element retainer. For better sealing, the abutment surfaces and mating surfaces can have more complex structures or geometries, such as a labyrinth seal. However, it is convenient to form a sealing portion between the sidewall of the filter element's head structure and the mating sealing surface on the filter element retainer that mates with the sidewall. This sealing portion can have a sealing element, such as a sealing ring or sealing compound, disposed between these elements. The sealing effect can be improved by special geometries of the sidewalls and / or the reverse sealing structure, for example, by applying a preload to the sealing element in the installed state.

[0019] A seal may be formed on the sidewall of the head structure such that the seal extends around the cleaning fluid outlet opening, which is formed in the head structure in a manner that is at least partially circumferentially surrounding the opening, particularly in a manner that is fully circumferentially surrounding it. Specifically, the seal may annularly surround the cleaning fluid outlet opening. As already noted, the seal does not bear, or only bears, a slight retaining force when the filter element is installed and therefore does not require a particularly robust or stable design.

[0020] Specifically, the sealing portion may have a sealing element extending transversely to the longitudinal direction to seal the filter element relative to the filter element retainer. This sealing element is particularly effective for separating the raw fluid space in which the raw fluid is located from the clean fluid space in which the clean fluid is located.

[0021] Recesses for receiving the sealing element can be formed in the sidewall, for example, as recesses formed as grooves. In particular, the recesses can extend generally orthogonally to the longitudinal direction, for example, in such a way that the grooves formed in the sidewall surround the cleaning fluid outlet opening in an annular manner. Such recesses ensure the fixed positioning of the sealing element on the sidewall, even when a preload is applied to the sealing element during the installation of the filter element in the filter element holder.

[0022] For example, the filter element may have a sealing element extending transversely to the longitudinal direction, which mates with the sidewall, specifically with a recess, to seal the filter element relative to the filter element retainer. The sealing element may be made of materials with elastic properties commonly used for sealing, such as synthetic rubber (EPDM, FKM / FPM, NBR), thermoplastic polyurethane, polytetrafluoroethylene, polyacetal, or silicone. The sealing element may be, for example, an O-ring, triangular ring, X-ring, or T-ring relative to its cross-section. However, the sealing element may also include fiber seals or foam seals. It is also conceivable that the sealing element has a varying cross-section in the circumferential direction surrounding the head structure. For example, in areas of the head structure where the filter element is expected to experience particularly large thermal expansion at operating temperatures, the sealing element may have a larger cross-section than in other areas. In this way, the greater elastic mass of the sealing element can be used to withstand such thermal expansion in areas where the filter element is expected to experience significant thermal expansion.

[0023] At least when the sealing element completely surrounds the cleaning fluid outlet opening, although a single sealing element is theoretically sufficient, in some embodiments the sidewalls may even have multiple recesses, allowing multiple sealing elements to be attached to the head structure. This can increase the seal between the filter element and the filter element container. Multiple sealing elements can also be arranged, each not completely surrounding the cleaning fluid outlet opening, with the multiple sealing elements offset from each other in a direction around the periphery of the cleaning fluid outlet opening.

[0024] The cleaning fluid outlet opening can be formed in the end wall located at the head end of the filter body. To prevent flow loss of the cleaning fluid from the filter element, the cleaning fluid outlet opening can occupy a major portion of the end wall, particularly 80% or more. It is also sufficient if the cleaning fluid outlet opening occupies only a portion of the end wall, such as approximately 70% to 80%.

[0025] The filter element may have a bag-shaped configuration having at least three sidewalls, particularly at least four sidewalls, and at least one bottom wall connecting these sidewalls to each other at a bottom end opposite the head end. The bag-shaped configuration may have an angled or circular cross-section. Specifically, the bag-shaped configuration may also have an elliptical or circular cross-section, making the filter element more similar to a tubular shape in a filter cartridge. At the head end of the filter element, a cleaning fluid outlet opening is formed in the head end wall. The sidewalls extend substantially parallel to the insertion direction, in which the filter element moves when inserted into the filter element holder. Typically, the flow direction of the cleaning fluid exiting the filter element is parallel to the insertion direction until it reaches the cleaning fluid outlet opening. The end walls extend generally transversely to the longitudinal direction, specifically orthogonal to the longitudinal direction, and also transversely to the flow direction of the cleaning fluid exiting the filter element. In particular, at least one bottom end wall forms the bottom or base of the filter bag.

[0026] When the filter element has four sidewalls, it can have a box shape that is both narrow and wide, with two wide sidewalls and two narrow sidewalls connecting the two wide sidewalls. The narrow sidewalls may extend orthogonally to the wide sidewalls. The wide sidewalls extend in the longitudinal and width directions of the filter element. The narrow sidewalls extend in the longitudinal and depth directions of the filter element.

[0027] In embodiments providing a sealing element that mates with the adjacent surface of the head structure, the sealing element may have a larger cross-section in the narrow sidewall region than in the wide sidewall region. The thickened portion of the sealing element in the narrow sidewall region accommodates increased thermal expansion of the filter element at higher temperatures (e.g., 50°C or higher). In the thickened region, the sealing element provides a more resilient mass that can be compressed to achieve length compensation as the filter element expands. Because the thermal expansion of the filter element primarily occurs in the direction of the wide sidewall, it is sufficient to design the sealing element to have a larger cross-section in the narrow sidewall region.

[0028] The sidewall area can form the filter body. Optionally, the bottom wall can also form part of the filter body. The bottom wall can also provide reinforcement and / or mounting guidance for the filter element.

[0029] A clean fluid space can be formed between the sidewalls, in which the clean fluid flows outward, formed by the original fluid after it passes through the sidewalls. The sidewalls, having bottom end walls, thus form a filter bag or filter pack. The sidewalls extend generally in the longitudinal direction, i.e., parallel to the longitudinal direction. Alternatively, the sidewalls may extend at an acute angle to the longitudinal direction, particularly at an angle less than or equal to 15°, and particularly diffuse from the bottom end to the top end, wherein the end wall formed at the top end has a larger area than the bottom end wall.

[0030] The cleaning fluid exits the filter element through the cleaning fluid outlet opening. Compressed air pulses generated by the purifying device can also be introduced into the filter element against the flow of the cleaning fluid through the cleaning fluid outlet opening, particularly towards the sidewalls and / or endwalls of the filter surface forming the filter element.

[0031] At least one of the two wide sidewalls may have a serrated or corrugated configuration, wherein the peaks and valleys have a generally longitudinally extending path in the filter element. The peaks and valleys typically extend from the head end of the filter element to the bottom end of the filter element.

[0032] The peaks and valleys in the head structure can flatten out toward the clean fluid outlet opening, so that the clean fluid outlet has a substantially rectangular cross-section for the clean fluid flow. In this respect, the cross-section of the clean fluid flow is maximized at the outlet opening (i.e., the clean fluid outlet), where the cross-section is almost rectangular.

[0033] The head structure can be configured to fix and hold the filter element on the filter element holder. Therefore, an additional holding structure for the filter element is not absolutely necessary.

[0034] To form the retaining structure, the head structure may have at least one outwardly protruding portion, which is configured to cooperate with a complementary or mating retaining structure formed on the filter element retainer to secure the filter element from displacement in the longitudinal direction, particularly from displacement in the insertion direction. In this respect, "outward" refers to the longitudinal direction, particularly orthogonal to the longitudinal direction, i.e., in the width direction and / or depth direction. In the installed state, the protrusion thus bears the force for holding or securing the filter element in the filter element retainer, particularly resisting displacement in the longitudinal direction.

[0035] The head structure may extend outward beyond at least one of the sidewalls (wide sidewalls and / or narrow sidewalls) in at least a portion thereof, such that the head structure itself forms a protrusion that forms an end face pointing toward the bottom end of the filter element and mates with a matching end face formed on the filter element holder to secure the filter element from displacement in the longitudinal direction, particularly from displacement in the insertion direction.

[0036] The filter element can be adapted to be suspended in the filter element holder of the filter device by engaging the end face pointing to the bottom end of the filter element with the matching end face of the filter element holder.

[0037] The cavity formed in the head structure (the cavity connecting the cleaning fluid outlet opening and the sidewall of the filter element, or the cleaning fluid space) can be separated by at least one partition wall extending generally in the longitudinal direction. This increases the stability of the head structure and thus ensures high durability.

[0038] A partition wall can connect two opposing wide sidewalls. The clean fluid space between the sidewalls can have an increasing cross-section from the first endwall at the bottom to the second endwall at the top.

[0039] The cavity or cavities of the cleaning fluid space and head structure can form an outlet funnel for cleaning fluid, the cross-section of which (funnel opening) increases with the distance from the bottom of the filter element.

[0040] The filter element can have an integrated design; specifically, the head structure can be integrally formed with the filter body. This allows the filter element to be manufactured in a fully automated manner, thus allowing for mass production. Integration means that the filter element (including the filter body, head structure, and bottom structure) is manufactured as a single piece. For example, a filter element including the filter body and head structure can be sintered or otherwise formed as a single piece. This manufacturing method is simpler than methods used to date, which required joining multiple separately sintered or molded parts together, or had to injection-molde or glue the head structure to the filter body in a separate step, and additionally required the attachment of metal reinforcements. In contrast, there are no intermediate or preliminary parts for the filter element according to the invention that must then be joined together. Furthermore, mechanical post-processing steps are largely unnecessary.

[0041] For example, the filter body can be manufactured from sintered granular material into a sintered structure, and the head structure can be integrally sintered with the filter body. The filter body and head structure can be composed of sintered plastic particles, particularly sintered polyethylene particles or sintered polyphenylene sulfide particles.

[0042] The filter body and head structure can be manufactured using infrared sintering. The thermal energy required for infrared sintering can be provided by gas or electricity. Infrared sintering, especially when the thermal energy is provided by electricity, makes it possible to sinter at different temperatures or energy values ​​in different regions of the filter element. This makes it possible to achieve particularly desired mechanical properties in certain regions, such as in terms of porosity and mechanical strength. This allows for different properties in the filter body (sidewall porosity) and the head structure (strength, flow-facilitating structure).

[0043] Filter elements can be further manufactured using additive manufacturing processes.

[0044] The filter element holder may include at least one mating abutment surface that engages with a seal on the sidewall of the head structure of the filter element to seal the filter element relative to the filter element holder, the seal extending transversely to the longitudinal direction.

[0045] The filter element holder may have sidewalls that extend generally in the longitudinal direction, and mating abutment surfaces may be formed at least partially, and in particular fully, circumferentially on the generally longitudinally extending sidewalls.

[0046] Specifically, both the filter element and the filter element holder may each have mutually associated sidewalls, such that a seal is formed between the two sidewalls when the filter element is installed. All the foregoing explanations regarding the possible configurations of the sidewalls of the head structure similarly apply to the sidewalls of the filter element holder; it should be understood that the two sidewalls may have a complementary configuration, or each sidewall may have a configuration corresponding to the sealing element.

[0047] The support plate for the filter element holder can be formed as a stamped and / or deep-drawn sheet metal part. Such sheet metal parts can be manufactured quickly and are easy to replace.

[0048] The filter element holder can be provided with multiple filter element containers, and individual filter elements can be inserted into each filter element container in such a way that the filter element is held in the filter element container by its head structure.

[0049] The filter element container may have a sealing structure that mates with an adjacent surface formed in the head structure of the filter element.

[0050] The filter element container may be formed as an opening in a support plate, the opening being surrounded by a flange that extends from the support plate and at least partially surrounds the opening. The flange may include a flange abutment surface configured to mate with a seal formed on the head structure of the filter element to seal the clean fluid space from the original fluid space.

[0051] The flange can extend away from the support plate in a generally longitudinal direction, especially parallel to the longitudinal direction.

[0052] The flange abutment surface may include a sealing and retaining structure, which may be specifically formed as a recess or groove. The sealing and retaining structure may be formed over the entire periphery of the flange abutment surface.

[0053] The filter element container can be designed such that the filter element can be inserted from the clean fluid space into the opening of the support plate (clean fluid side mounting), or the filter element can be attached from the raw fluid space to the opening of the support plate (raw fluid side mounting).

[0054] The filtration device may also include a sealing element disposed between the filter element and the filter element holder, specifically between the side surface of the filter element formed on the head structure and the corresponding mating adjacent surface of the filter element holder.

[0055] Preferably, the filter element retainer can form a partition in the filter device between the original fluid space and the clean fluid space, such that the original fluid space is sealed from the clean fluid space together with one or more filter elements according to the invention.

[0056] The filter body and head structure can be manufactured by a sintering process, particularly by infrared sintering. Preferably, plastic granules can be used for this purpose, which are then sintered together to form the filter element.

[0057] The head structure and the filter body can be manufactured as a single unit. This enables rapid production of filter elements, which can also be fully automated.

[0058] All the advantages and embodiments explained above with reference to the filter element and filter element holder are also applicable to the manufacture of the filter device and filter element according to the present invention, and will not be explained again to avoid repetition. Attached Figure Description

[0059] The invention will now be described in more detail with reference to the exemplary embodiments shown in the accompanying drawings.

[0060] Figure 1 A filter element according to the present invention is shown.

[0061] Figure 2 A filter element according to the invention for mounting on the clean fluid side is shown, as well as a filter element holder according to the invention in the state of the filter element being inserted into a filter element holder.

[0062] Figure 3 A filter element according to the invention is shown installed in a filter element holder according to the invention.

[0063] Figure 4 It shows the head structure Figure 3 An enlarged partial sectional view.

[0064] Figure 5A variant of a filter element with a sealing element according to the invention is shown, the sealing element having a thickened portion in a circular region on the narrow side of the filter element.

[0065] Figure 6 A detailed illustration of a variant of the filter element according to the invention for installation on the original fluid side is shown.

[0066] Figure 7 A filtration device having a filter element according to the invention and a filter element retainer according to the invention is shown.

[0067] Figure 8 It shows the manufacturing process. Figure 1 The process sequence of the filter elements shown.

[0068] In all the accompanying drawings, the same reference numerals denote parts that are identical or similar in function. Each of these parts is described in detail only with reference to the embodiment in which the corresponding reference numerals are used for the first time. It should be understood that the corresponding explanations also apply to other embodiments in which the corresponding reference numerals are used. To avoid repetition, unless otherwise expressly stated, explicit references are made to the corresponding descriptions upon first use of the corresponding reference numerals. Detailed Implementation

[0069] Figure 1 A filter element 2 is shown, which has a flow-through porous filter body 4 extending between a head end and a longitudinally opposite bottom end.

[0070] The filter element 2 has two wide sidewalls 22 and two narrow sidewalls 24 connecting the wide sidewalls. Figure 1 Only one sidewall 22 and one sidewall 24 are shown in the diagram. All sidewalls 22 and 24 extend substantially in the longitudinal direction. The wide sidewall 22 extends in both the longitudinal and width directions of the filter element 2. The narrow sidewall 24 extends orthogonally to the wide sidewall 22 in both the longitudinal and depth directions of the filter element 2. The sidewalls 22 and 24, together with the bottom wall (not shown) disposed at the bottom end of the filter element 2, form a filter bag or filter pack and surround the filter body cavity.

[0071] The outward-facing side surfaces of sidewalls 22 and 24 face the original fluid space in the installed state. The original fluid space contains the original fluid contaminated with foreign matter and particles. When the original fluid passes through filter element 2, the foreign matter and particles are filtered out, allowing clean fluid, free of foreign matter and particles, to enter the filter body cavity. During operation of filter element 2, the clean fluid, free of foreign matter and particles, flows out of the filter body cavity through clean fluid outlet opening 16 after passing through the filter element. The filter body cavity thus forms part of the clean fluid space located on the clean fluid side of the filter element.

[0072] The wide sidewalls 22 have a serrated or corrugated shape, giving the filter bag a layered configuration. The peaks and valleys of the sidewalls 22 have routes extending substantially in the longitudinal direction of the filter body 4. The peaks and valleys flatten towards the head end of the filter element 2 in the head structure 6, giving the cleaning fluid outlet opening 16 a substantially rectangular cross-section. This cross-section enhances the outflow of cleaning fluid from the filter chamber of the filter element 2. As an alternative to the layered configuration shown, the sidewalls 22 can also be formed as flat plates. In forms not shown, the filter bag can also be formed from only three sidewalls or from more than four sidewalls. It is also possible that the sidewalls 22, 24 are arranged at an angle to each other, and the cross-section of the filter chamber surrounded by the sidewalls 22, 24 increases towards the cleaning fluid outlet opening 16. The filter bag then has a slightly funnel-shaped or pyramidal configuration. Furthermore, it is possible to form filter bags with circular or even elliptical or arcuate cross-sections, wherein the filter bag is in a tubular truncated conical or conical shape. The side walls 22 and 24 can even contact each other at the bottom of the filter element, thus eliminating the need for a bottom wall.

[0073] A head structure 6 is formed at the head end of the filter element 2. The head structure 6 includes a longitudinally extending sidewall 8 formed circumferentially around the cleaning fluid outlet opening 16. The sidewall 8 includes two longer / wider portions positioned opposite each other and extending in the width direction of the filter element 2, and two shorter / narrower portions positioned opposite each other and extending in the depth direction of the filter element 2, wherein the two shorter / narrower portions connect the two longer / wider portions to each other at corresponding ends of the filter element 2. These shorter / narrower portions are rounded on their outer sides. A sealing portion 10 is disposed on the outer side of the longitudinally extending sidewall 8, and the sealing portion 10 is configured relative to... Figure 1 The filter element retainer (not shown) seals the filter element 2 (see...). Figure 2 and Figure 3 The sealing portion 10 may have a recess 11 formed in the sidewall 8 and a sealing element 12 disposed in the recess 11. The sealing element 12 may be designed as a separate seal in the form of an O-ring, triangular ring, X-ring, T-ring, foam seal, or fiber seal. In the illustrated embodiment, the recess 11 has a groove formed in the sidewall 8 that extends orthogonally to the longitudinal direction around the entire sidewall 8 and thus completely surrounds the cleaning fluid outlet opening 16. The sealing portion 10 thus extends along the periphery of the head structure 6 and around the cleaning fluid outlet opening 16 along the sidewall 8. Another sealing structure (e.g., a raised edge) may also be formed on the outer side of the sidewall 8 to which the sealing element 12 mates, or even the sealing element 12 may mate with the unconstructed outer side of the sidewall 8.

[0074] exist Figure 1In the illustrated embodiment, the sealing portion 10 is formed of a sealing element 12 that mates with the filter element holder. Embodiments in which the sealing element 12 is not required are also conceivable. For example, the sealing portion 10 may have an abutting surface formed, for example, on a groove formed in the sidewall 8 or on a protrusion or material extension extending from the sidewall 8. In such an embodiment, the filter element holder into which the filter element 2 is inserted will have matching abutting surfaces with corresponding complementary structures, such that a labyrinth seal is achieved when the filter element is inserted. In another alternative embodiment, the sidewall 8 may have a material structure in a region that provides a sealing effect between the sidewall 8 and the filter element holder when abutting against it. This can be achieved by machining the sidewall 8 differently in the region where it is provided for sealing compared to the rest of the sidewall 8, such as having a rougher surface than the rest of the sidewall 8.

[0075] A sealing portion 10 is formed in the region of the sidewall 8 near the head end of the filter element 2. Different locations of the sealing portion 10 on the sidewall 8 are also possible. The head structure 6 may further include a plurality of sealing portions 10, arranged longitudinally one after another to form multiple fluid barriers. This can provide greater security in separating the clean fluid space from the original fluid space.

[0076] The head structure 6 also includes a head side end wall 14, which is disposed at the head end of the filter element 2 and forms a cleaning fluid outlet opening 16 therein. The side walls 8 of the head structure 6 surround the cleaning fluid outlet opening 16 as a circumferential outer boundary. In addition to two shorter segments of the side walls 8, two opposing longer segments of the side walls 8 are connected to each other by a total of seven webs 18, such that the cleaning fluid outlet opening 16 is divided into eight partial cleaning fluid outlet openings. It should be understood that fewer or more partial cleaning fluid outlet openings are also possible. It is even possible that no webs 18 are present, such that the head structure 6 has a continuous cleaning fluid outlet opening 16 surrounded by the side walls 8. The two narrower portions of the side walls 8 extend in the depth direction and limit the head structure 6 in the width direction. Figure 1 In the illustrated embodiment, the narrower portion of the sidewall 8 is rounded on its outer side, making it convex. Therefore, the sidewall 8 has an outwardly curved outer surface in the narrower region. Alternatively, the narrower portion of the sidewall 8 may also be formed in a straight line or even be concave on its outer side. The convex rounded design of the narrower section of the sidewall 8 allows for reduced stress in the head structure 6, particularly stress due to temperature fluctuations, and thus increases the durability of the filter element 2. This is especially effective when the filter element is subjected to higher operating temperatures. Furthermore, the convex rounded shape of the narrower portion of the sidewall 8 facilitates the installation and removal of the filter element 2.

[0077] The head structure 6 is configured to insert the filter element 2 into Figures 2 to 4 The filter element holder 26 shown is held in order to operate in the filter device. Figure 2 A filter element 2 is shown in a configuration mounted on the clean fluid side, wherein the filter element 2 is inserted from the clean fluid space into the filter element holder 26. Figure 2 The filter element 2 is shown in a position during installation, in which the filter element 2 has not yet reached its final position, but is in an intermediate position on its way to its final position. Figure 3 The filter element 2 is shown in its final position within the filter element holder 26.

[0078] The filter element holder 26 has a support plate 28 in which at least one filter element container 30 is formed. The support plate 28 may be formed, for example, as a stamped or deep-drawn sheet metal part, wherein the filter element container 30 has an opening 31 stamped from the sheet metal part and a flange 40 attached to the edge of the opening 31. (As in...) Figure 4 As can be seen in the cross-sectional view, the sidewall 8 of the head structure 6 may form at least one outwardly extending protrusion 36, on which an end face 38 facing the bottom end of the filter element 2 is formed. Alternatively, such a protrusion may extend outwardly from the head structure 6 in the region of the sidewall 8. When the filter element 2 is inserted into the filter element holder 26, the end face 38 formed on the head structure 6 in the end position abuts against the mating abutment surface 34 of the filter element holder 26, which prevents the filter element 2 from further displacing relative to the filter element holder 26 in the insertion direction.

[0079] exist Figure 3 In the installation position shown, the filter element 2 is inserted into and held in the filter element container 30 with its head structure 6. For installation, the filter body 4 of the filter element 2 first passes through the opening 31 of the filter element container 30 from the clean fluid side in the insertion direction with its bottom end, until the protrusion 36 formed on the head structure 6 (which forms the holding structure) abuts against the matching abutment surface 34 of the protrusion 32 formed on the filter element container 30 through the end surface 38 pointing towards the bottom end of the filter element 2, thereby preventing further movement of the filter element 2 in the insertion direction.

[0080] In the installed state, the filter body 4 extends into the original fluid space of the filter device (not shown), and the head structure 6 is partially arranged in the clean fluid space. As will be explained in more detail below, the head structure 6 thus seals the clean fluid space relative to the original fluid space by means of the abutment of the sealing element 12 on the flange 40, and also ensures that the filter element 2 is supported on the support plate 28 by the end face 38 abutting against the mating abutment surface 34.

[0081] The flange 40 of the filter element container 30 surrounding the opening 31 extends approximately orthogonally away from the support plate 28 in the longitudinal direction. The end 42 of the flange 40 facing away from the support plate 28 is radially bent outward to form an insertion aid, which facilitates the insertion of the head structure 6 into the receiving space 41 formed by the flange 40 when the filter element 2 is inserted. The flange is preferably arranged to be slightly recessed from the edge of the opening 31 and is formed to precisely fit the protrusion 36 on the head structure 6. In this way, the portion of the support plate 28 extending toward the edge of the opening 31 forms the protrusion 32, which has a mating abutment surface 34, and the end face 38 formed on the protrusion 36 of the head structure 6 of the filter element 2 abuts against the mating abutment surface 34.

[0082] The flange 40 has an inner surface 42 with a flange abutment surface 44, which is positioned opposite the seal 10 of the head structure 6 when the filter element 2 is installed. The flange abutment surface 44 is configured to seal the original fluid space from the clean fluid space together with the seal 10 (shown as sealing element 12 in the example). The flange abutment surface 44 may include a recess or groove configured to provide a fitting fit of the seal 10 in the installed state. When using the sealing element 12, the recess or groove may be specifically configured to receive the sealing element 12. The flange abutment surface 44 is preferably arranged completely circumferentially around the inner surface 42 of the flange 40.

[0083] The design of the filter element and filter element holder according to the invention provides, in addition to the sealing structure (which functions to separate the original fluid space from the clean fluid space), and particularly in addition to the sidewall 8, the flange abutment surface 42, and (if applicable) the sealing element 12, an additional structure for retaining the filter element 2 in the filter element holder 26, particularly the protrusions 32, 36. As shown, this design, in which the sealing structure does not have to withstand the forces required to hold or securely support the filter element 2 in the filter element holder 26, allows for very easy and better automated manufacturing of the filter element 2 and the filter element holder 26.

[0084] In an exemplary embodiment, the filter element 2 is integrally formed. This means that the filter body 4 and the head structure 6 are made of the same material. The material can be a sintered particulate material, particularly sintered plastic granules. Nevertheless, the filter body 4 and the head structure 6 can have different configurations, or there may be structural differences between the filter body 4 and the head structure 6. Specifically, for the filter body 4, it is desirable to have a sufficiently porous structure that allows the fluid to be filtered to pass through with an acceptable pressure loss. On the other hand, for the head structure 6, sufficient rigidity is primarily sought to securely receive and support the filter element 2 in the filter element holder 26. For this purpose, the filter element 2 can be manufactured, in particular, by infrared sintering. This allows for easy control of the porosity of the filter element in the regions forming the filter body 4 and the head structure 6, wherein the regions of the filter body 4 have a different porosity than the regions in which the head structure 6 is formed. Specifically, the filter body 4 has a higher porosity than the head structure 6. In contrast, the head structure is formed more rigidly than the filter body, i.e., more robustly sintered together.

[0085] Figure 5 A variant of the filter element 2 according to the invention is shown, wherein the sealing element 12 has thickened portions 12A in two circular regions on the narrow side of the filter element 2. It should be noted again that... Figure 5 Used with Figures 1 to 4 The same reference numerals are used in the accompanying drawings, provided that in each case they denote the same or similar parts in terms of their function. In the following, only the reference numerals will be explained in more detail. Figure 5 For differences in the embodiments and for explanations of other components, please refer to [reference needed]. Figures 1 to 4 The description, Figures 1 to 4 The description also applies to... Figure 5 Examples of implementations.

[0086] Also according to Figure 5 In one embodiment, the head structure 6 includes a longitudinally extending sidewall 8 formed circumferentially around a cleaning fluid outlet opening 16. The sidewall 8 includes two longer portions positioned opposite each other and extending in the width direction of the filter element 2, and two shorter portions positioned opposite each other and extending in the depth direction of the filter element 2, the two shorter portions connecting the two longer portions to each other at corresponding ends of the filter element 2. These shorter portions are rounded at their outer sides. A groove 11 is formed on the outer side of the sidewall 8, extending around the cleaning fluid outlet opening 16, and a sealing element 12, formed as a sealing ring, is received in the groove 11. In the illustrated exemplary embodiment, the sealing element 12 has a substantially arcuate cross-section.

[0087] It has been found that filter element 2 can exhibit significant thermal expansion when subjected to temperatures of 50°C or higher during operation. This thermal expansion is particularly significant in the width direction of filter element 2 compared to the direction parallel to the longer side surface 22. Therefore, based on... Figure 5 In this embodiment, compared to other portions of the sealing element 12, the sealing element 12 is formed with a larger cross-section in the shorter circular portion of the sidewall 8 that extends in the depth direction and connects the two longer portions. The sealing element 12 therefore has thickened portions in these portions, which... Figure 5 It is shown in the figure by reference numeral 12A. Figure 5 As can be seen, the sealing element 12 adopts a more elliptical cross-section in the region of the thickened portion 12A, wherein the maximum extension of the thickened portion 12A points in the width direction of the filter element 2. However, it should be emphasized that the design shown for the sealing element 12 with the thickened portion 12A is also possible and useful when using sealing elements with different cross-sectional shapes (e.g., rectangular or trapezoidal) to compensate for the strong thermal expansion of the filter element 2 in a certain direction.

[0088] Because the cross-section of the sealing element 12 is larger in the thickened portion or thickened section 12A region, the sealing element can be compressed to a greater extent in the direction of its maximum cross-section in the thickened portion 12A region compared to other regions of the sealing element 12. In a sense, the compression path is extended, through which the sealing element 12 can be compressed. The thickened portion 12A is formed such that the direction of the maximum cross-section in the region of the thickened portion 12A points towards the width direction of the filter element 2, that is, towards the direction in which the filter element 2 undergoes maximum thermal expansion during operation. In this way, the thickened portion 12A of the sealing element 12 provides an additional amount of elastic or compressible material that can be compressed when the thermal expansion of the filter element 2 occurs mainly in the width direction. Thus, the sealing element 12 compensates for the additional thermal expansion of the filter element 2 in the width direction.

[0089] Figure 6 A detailed view of a variant of the filter element 2, according to the invention, installed in the filter element holder 70, is shown from the original fluid side. Figure 6 Also used in China Figures 1 to 5 The same reference numerals are used in the accompanying drawings, provided that in each case they denote the same or similar parts in terms of their function. In the following, only a more detailed explanation is given of the reference numerals. Figure 6 The differences in the embodiments, and in order to clarify the additional components, refer to Figures 1 to 5 The description, similarly applicable to, is based on Figure 6 Examples of implementations.

[0090] The filter element holder 70 includes a support plate 72 with an opening 74. Surrounding the opening 74 is a flange 76 that extends longitudinally away from the support plate 72 and, together with the support plate 72, surrounds the filter element container 78. In the installed state, the flange 76 extends into the original fluid space of the filtration device. The filter element support 70 and flange 76 are formed similarly to the filter element support 26 and flange 40. When the filter element 2 is installed, its head structure 6 is inserted from the original fluid side into the space formed between the flange 76 and the support plate 72. The flange 76 and the support plate 72 form the filter element container 78, such that the sidewall 8 of the head structure 6 of the filter element 2 is positioned relative to the flange abutment surface 80 formed on the inner side of the flange 76, and the head structure 6 is primarily located in the original fluid space. Between the sidewall 8 and the flange abutment surface 80, a sealing element 12 is positioned to seal against the sidewall 8 and the flange abutment surface 80. In the installed state, the filter element 2 is secured to the support plate 72 by fasteners (not shown), for example by a clamp or sheet metal piece attached from the raw fluid side to the flange 76 or support plate 72 and engaging with the protrusion 36 formed on the head structure 6 of the filter element 2, such that the head structure 6 is clamped between the support plate 72 and the clamp or sheet metal piece. Alternatively, the head structure can also be secured by screws or the like, passing through the support plate 72 from the clean fluid side and screwed into the threads in the head structure 6. Another possibility is that one or more screws or bolts are screwed into the head structure 6 through the flange 76.

[0091] Figure 7 A filter device 100 is schematically shown, including a housing 102 having a raw fluid inlet 104 and a clean fluid outlet 106. Within the housing 102, a filter element holder 26 with inserted filter elements 2 is arranged such that the filter element holder 26 and the filter elements 2 separate a raw fluid space 108 from a clean fluid space 110, with the raw fluid inlet 104 opening to the raw fluid space 108 and the clean fluid space 110 connecting to the clean fluid outlet 106. In the filter device 100, the filter element holder 26 is arranged horizontally, and the filter elements 2 extend orthogonally into the raw fluid space 108. Figure 7 The image shows a clean fluid side mounting type for the filter element 2 in the filter element holder 26. This means that the filter element 2 is mounted from the clean fluid space 110 into the filter element holder 26 and extends through the filter element holder 26 into the original fluid space 108. Figures 1 to 5 The image shows a filter element 2 suitable for installation on the clean fluid side. As such... Figure 7As shown in the alternative installation on the clean fluid side, the filter element 2 can also be installed in the filter element holder 26 on the raw fluid side. For this purpose, the filter element 2 is placed from the raw fluid space 108 onto the filter element holder 26 with its head structure. Figure 6 The image shows a filter element 2 suitable for installation on the clean fluid side.

[0092] As an alternative to the horizontal orientation of the filter element holder 26, the filter element holder can also be arranged vertically relative to the housing 102 or at different angles. This means that, in alternative embodiments, the filter element 2 can also have different orientations relative to the housing 102.

[0093] Figure 8 A process flow for manufacturing filter element 2 is shown, wherein the manufacturing of filter element 2 is automated. The method includes manufacturing a flow-through porous and inherently stable filter body 4, and forming a head structure 6 on the filter body 4. In this case, the head structure 6 is provided with at least one sealing portion 10, which is configured to cooperate with the filter element holder 26 of the filter device 80 to seal the clean fluid space 110 relative to the original fluid space 88.

[0094] In the first step 200, particulate plastic material is preferably filled into a sintering mold. In step 202, the sintering mold is heated, causing the particulate plastic material to form a flow-through porous and inherently stable filter body 4. In the region where the head structure 6 of the filter element 2 is formed on or together with the filter body 4, the sintering mold is heated differently or more intensely, resulting in a more rigid and virtually fluid-impermeable material structure in the region of the head structure 6. The transition between the filter body 4 and the head structure 6 has a lower porosity than the filter body 4 and a higher porosity than the head structure 6. The sintering mold may include structures for forming the sealing portion 10, or in any case for forming structures belonging to the sealing portion 10, such as recesses or grooves 11 for receiving the sealing element 12. Alternatively, the sealing portion 10 may also be formed in a step after the sintering process, which may also be automated. To achieve different heating zones in the area where plastic material is filled into the sintering mold to form the filter body 4 and the area where plastic material is filled into the sintering mold to form the head structure 6, sintering can be specifically performed by infrared sintering. In this way, it is particularly easy to control the corresponding desired porosity or hardness of the filter element 2 in different areas. The method can be carried out in such a way that the filter body 4 and the head structure 6 are integrally formed or formed as a single piece. For this reason, it is not necessary to use additional fasteners to connect the filter body 4 and the head structure 6. After the filter element 20 has cooled in the sintering mold, it can be removed from the sintering mold in step 204. This is preferably done by opening the sintering mold and lifting the filter element out of the sintering mold.

Claims

1. A filter element (2) comprising a flow-through porous filter body (4) extending between a head end and a longitudinally opposite bottom end; in, A head structure (6) is formed at the head end of the filter element (2), the head structure (6) having at least one sealing portion (10), the at least one sealing portion (10) being configured to seal the filter element (2) relative to the filter element retainer of the filter device, the filter element retainer fixing and supporting the filter element. The head structure (6) has a longitudinally extending sidewall, and the sealing part (10) is formed on the longitudinally extending sidewall of the head structure (6) of the filter element (2). The filter element (2) is configured such that other parts or structures on the head structure (6), excluding the seal (10), provide the function of securely fastening and supporting the filter element (2) in the filter element holder. The filter body (4) is formed of sintered particulate material, and the head structure (6) is integrally sintered with the filter body.

2. The filter element (2) according to claim 1, in, The sealing portion (10) is formed on the sidewall of the head structure (6) so as to extend at least partially circumferentially around the cleaning fluid outlet opening (16) formed in the head structure (6).

3. The filter element (2) according to claim 1, in, The sealing portion (10) has a sealing element (12) extending transversely to the longitudinal direction to seal the filter element (2) relative to the filter element retainer.

4. The filter element (2) according to claim 3, in, The sidewall has a recess (11) for receiving the sealing element (12).

5. The filter element (2) according to claim 4, It further includes a sealing element (12) that extends transversely to the longitudinal direction and engages with the recess (11) to seal the filter element (2) relative to the filter element retainer.

6. The filter element (2) according to claim 3, in, The sealing element (12) includes an O-ring, a triangular ring, an X-ring, a T-ring, a foam seal, or a fiber seal.

7. The filter element (2) according to claim 4, in, The sidewall includes multiple recesses (11).

8. The filter element (2) according to claim 2, in, The cleaning fluid outlet opening (16) is formed in the end wall arranged at the head end of the filter body (4).

9. The filter element (2) according to claim 1, in, The filter element (2) includes at least three sidewalls and at least one bottom wall that connects the sidewalls to each other at the bottom end.

10. The filter element (2) according to claim 9, in, The filter element (2) includes two wide sidewalls (22) and two narrow sidewalls (24) connecting the two wide sidewalls (22) to each other, wherein the area of ​​the sidewalls forms the filter body.

11. The filter element (2) according to claim 9, in, A clean fluid space is formed between the sidewalls, and the clean fluid flows out of the clean fluid space. The clean fluid is formed from the original fluid after the original fluid passes through the sidewalls.

12. The filter element (2) according to claim 10, in, At least one of the two wide sidewalls (22) is formed in a sawtooth or corrugated manner, wherein the peaks and valleys of the at least one wide sidewall have routes extending in the longitudinal direction of the filter element (2).

13. The filter element (2) according to claim 12, in, The peaks and valleys in the head structure (6) flatten out toward the head end, such that the cleaning fluid outlet opening (16) formed in the head structure (6) has a rectangular cross-section for the flow of cleaning fluid.

14. The filter element (2) according to claim 1, in, The head structure (6) is configured to fix the filter element (2) to the filter element holder.

15. The filter element (2) according to claim 14, in, The head structure (6) forms at least one outwardly protruding portion (36) adapted to cooperate with a retaining structure (32) formed on the filter element retainer to fix the filter element (2) from displacement in the longitudinal direction.

16. The filter element (2) according to claim 14, in, The head structure (6) extends outward in the region of the sidewall, at least in a portion of the region, such that the head structure (6) forms a protrusion, the protrusion forming an end face (38), the end face (38) pointing to the bottom end of the filter body and engaging with a matching end face (34) formed on the filter element holder to fix the filter element (2) from displacement in the longitudinal direction.

17. The filter element (2) according to claim 1, in, The filter body (4) and the head structure (6) are made of plastic granules sintered together.

18. The filter element (2) according to claim 1, in, The filter body (4) and the head structure (6) are manufactured by infrared sintering.

19. The filter element (2) according to claim 1, in, The filter element (2) can be manufactured by additive manufacturing process.

20. A filter element holder adapted to receive a filter element (2) according to any one of claims 1 to 19 for securing and supporting the filter element (2), the filter element holder comprising: Support plate (28; 72), the support plate (28); 72) Having at least one filter element container, the filter element (2) being able to be inserted into the at least one filter element container in such a way that the filter element (2) is mounted in the filter element container via its head structure (6); The filter element container includes a sealing structure that cooperates with the sealing portion (10) formed in the head structure (6) of the filter element. The filter element holder is configured such that the filter element (2) is securely fastened and supported in the filter element holder by means of other parts or structures on the head structure (6) other than the seal (10); The support plate (28; 72) includes stamped and / or deep-drawn sheet metal parts; The filter element container includes a flange (40; 76) extending longitudinally away from the support plate (28; 72). The flange (40; 76) includes a flange abutment surface (44; 80) adapted to mate with the sealing portion (10) of the filter element (2) to seal the original fluid space from the clean fluid space.

21. The filter element holder according to claim 20, in, A sealing and retaining structure is formed on the adjacent surfaces (44; 80) of the flange, and the sealing and retaining structure is adapted to receive the sealing portion (10) disposed on the sidewall of the head structure (6); The sealing and retaining structure is formed to extend over the entire periphery of the flange abutment surface (44; 80).

22. A combination of a filter element (2) according to any one of claims 1 to 19 and a filter element holder according to claim 20 or 21, wherein the filter element (2) is insertable into the filter element holder such that, in the inserted state, the filter element (2) separates the original fluid space of the filtration device from the clean fluid space. in, The sidewall of the head structure (6) and the filter element container cooperate to seal the filter element (2) relative to the filter element retainer.

23. A filtration device (100), comprising: Original fluid space (108); Clean fluid space (110); The filter device (100) comprises at least one combination of at least one filter element (2) and at least one filter element holder according to claim 22. The filter element (2) is inserted into the filter element container formed in the filter element holder, such that the filter element (2) in the inserted state separates the original fluid space from the clean fluid space.

24. A method for manufacturing a filter element (2) according to any one of claims 1 to 19, comprising: Producing a porous and inherently stable filter body (4), and A head structure (6) is formed on the filter body (4), wherein the head structure (6) is provided with at least one sealing portion (10), the at least one sealing portion (10) being adapted to cooperate with a filter element holder of the filter device (100) to seal the clean fluid space of the filter device (100) from the original fluid space, wherein the filter element (2) is configured such that other parts or structures on the head structure (6) besides the sealing portion (10) provide the function of securely fastening and supporting the filter element (2) in the filter element holder. The filter body (4) is formed of sintered particulate material, and the head structure (6) is integrally sintered with the filter body, and the manufacturing of the filter element (2) is automated.

25. The method according to claim 24, in, The sealing portion (10) includes a sealing element (12) extending transversely to the longitudinal direction, the sealing element (12) for sealing the filter element (2) relative to the filter element retainer.

26. The method according to claim 24, in, The head structure (6) is provided with a longitudinally extending sidewall, and the sealing part (10) is formed on the longitudinally extending sidewall.

27. The method according to any one of claims 24 to 26, in, The head structure (6) is configured to cooperate with the filter element holder of the filter device (100) to fix the filter element (2) in the filter element holder.

28. The method according to any one of claims 24 to 26, in, The filter body (4) and the head structure (6) are produced by infrared sintering.

29. The method according to any one of claims 24 to 26, in, The head structure (6) and the filter body (4) are manufactured as a single piece.

Images