Filter element with frame, filter system and use

Abstract

Filter element (10) for filtering a fluid comprising - at least one filter bellows (12) with a designated raw side (52) and a designated clean side (50) opposite it, made of a filter medium (14) which is folded in a zigzag pattern into folds (34) along fold edges (26) which extend between opposite end faces (22a, 22b) of the filter bellows (12), and which has end face surfaces (20a, 20b) running parallel to each other on opposite end faces (18, 19) and end faces (24a, 24b) on end faces (16, 17) lying transversely to them, - a frame (28) extending along the end faces (16, 17, 18, 19), wherein the frame (28) is open to the raw side (52) and to the clean side (50) to allow the fluid to flow through, wherein the filter bellows (12) is rigidly connected to the frame (28), and wherein the frame (28) has a transverse web (30) extending between two opposing side faces (32a, 32b) of the frame (28) and is rigidly connected to the filter bellows (12), wherein the web (30) is integrally connected to the frame (28), characterized in that the web (30) has a removal handle (36).

Description

Technical field

[0001] The invention relates to a filter element for filtering a fluid with a frame and a filter system, in particular for use as a fuel filter for an internal combustion engine, especially a motor vehicle. State of the art

[0002] Filter elements used in automotive manufacturing, for example, often consist of a zigzag-folded nonwoven fabric reinforced with frame elements, some of which are produced by thermoplastic welding of the nonwoven. A disadvantage of such filter elements is their inherent instability. Particularly under pressure surges, there is a risk of the folds buckling or collapsing. This significantly reduces the filtering efficiency and / or greatly increases the flow resistance.

[0003] From EP 0 863 785 B1, a filter element is known which consists of a zigzag-folded filter medium, in particular nonwoven fabric or paper, and which is manufactured in the form of a flat plate. A frame is provided along the end faces. The flat plate is fixed in the frame. Furthermore, webs extending transversely across the plate are provided, with at least one web having at least one sword segment. The sword segment extends into folds of the zigzag-folded filter medium and stabilizes it. The filter material is partially supported, i.e., it is supported in the areas where increased deflection may occur. This does not impair the effective filter area, or only to a very small extent. The support is provided from the raw air side, i.e.,The sword segment engages in the raw air fold, supports the plate in the direction of airflow, and simultaneously prevents the folds from buckling. The sword segment has a perforation. This perforation forms pockets suitable for filling with adhesive or glue.

[0004] DE 201 15 642 U1 describes a flat pleated filter element, wherein a stabilizing grid made of flexible plastic is attached to the downstream flat side.

[0005] DE 20 2005 015 126 U1 discloses a filter element comprising a stabilizing element designed as a bridge. The bridge is held between two opposite ends of two folded filter webs. A fastening device for attaching the bridge to a filter housing is provided on the raw or clean side.

[0006] From WO 2014 / 120 957 A1, a filter device with a pleated filter element is known, which has a bellows and a surrounding frame. The frame is at least partially injection-molded onto the medium, so that the medium is fixed within the frame. The filter medium comprises at least two media types of different densities.

[0007] DE 101 53 642 B4 describes a round filter element with two filter medium parts and a pleated stabilizing agent arranged on inner end faces between the filter medium parts, wherein the stabilizing agent consists of a thermally softenable material and encloses the filter medium parts in a form-fit or force-fit manner.

[0008] DE 195 08 534 A1 discloses a filter body formed as a plate-shaped element with a frame enclosing the element, which is made of at least two frame parts connected to each other in the plane of the plate-shaped element.

[0009] US Patent 2010 / 0236204A1 discloses a filter element comprising a bellows, support grid, and frame. At least one comb-like element with a plurality of spaced, tapered teeth extends outward toward the filter medium, such that the teeth engage in fold spaces to regulate fold separation and spacing. Disclosure of the invention

[0010] One object of the invention is to create a filter element for filtering a fluid that has high stability and is easy to assemble and maintain.

[0011] Another task is to create a filter system for filtering a fluid to accommodate such a replaceable filter element, which has high stability and is easy to assemble and maintain.

[0012] The aforementioned problem is solved according to one aspect of the invention by a filter element comprising at least one filter bellows and a frame, wherein the filter bellows is rigidly connected to the frame, and wherein the frame has a transverse web extending between two opposite side surfaces of the frame and rigidly connected to the filter bellows, wherein the web is integrally connected to the frame and has a removal handle.

[0013] Favorable embodiments and advantages of the invention will become apparent from the further claims, the description and the drawing.

[0014] A filter element for filtering a fluid, particularly for use as a fuel filter in an internal combustion engine, especially in a motor vehicle, is proposed. The element comprises at least one filter bellows with a designated raw side and a designated clean side opposite it. The filter medium is made of a filter medium folded into zigzag folds along fold edges, each extending between opposite end faces of the filter bellows. The filter medium has end face surfaces parallel to each other on opposite end faces and end faces transverse to these. The filter element further comprises a frame extending along the end faces, the frame being open to the raw side and the clean side to allow fluid flow. The filter bellows is rigidly connected to the frame.Furthermore, the frame has a transverse web that extends between two opposite side surfaces of the frame and is firmly connected to the filter bellows.

[0015] In the solution according to the invention, the filter bellows is embedded in a surrounding frame and firmly connected to it. This can be achieved by bonding, encapsulating, or overmolding the filter bellows with a plastic material. A web, also firmly connected to the frame, extends, for example, from one side surface to an opposite side surface by dividing the inner surface of the frame. The web is also firmly connected to the filter bellows. The web can be bonded, encapsulated, or produced by overmolding the filter bellows together with the frame. In this way, the filter bellows, frame, and web form a structural unit that can be installed and removed as a whole in a filter system.The frame also ensures a reliable seal of the end faces, particularly when the frame is manufactured by overmolding the filter bellows with plastic. In an alternative embodiment, it is also conceivable to arrange two filter bellows within the frame, which are injected into the frame on both sides of the web and are thus firmly attached to both the frame and the web.

[0016] The filter element according to the invention combines effective pleat support with a stable removal tab, which allows the filter element to be removed from a filter system even if it is stuck. This is achieved by means of the bridge, which is firmly connected to the surrounding frame, which is made of plastic, for example, and in which the filter bellows is embedded. The bridge also adheres to the pleats of the filter bellows. The pleats are stabilized, and the filter element can be reliably removed from a filter housing, for example, using a tab located on the bridge. No parts can get onto the clean side of the filter system, and damage to the filter bellows by the removal aid, such as a tab, is avoided.

[0017] Advantageously, the bridge can have a depth at least equal to the fold depth of the filter bellows. In this way, the bridge can stabilize the filter bellows along its entire fold depth, for example, by being connected, glued, or embedded across the entire surface of two adjacent folds. Even if the bridge is only connected to the folds at their base, this results in advantageous stabilization, offering benefits compared to a bridge connected only at an upper edge and significantly better stabilization than an unconnected filter bellows.

[0018] According to an advantageous embodiment, the bridge can be arranged transversely to the pleats. Such an arrangement has the advantage that all pleats of the filter bellows connected to the bridge are held and stabilized by the bridge. This provides the filter bellows with additional support and stability between the frame's side surfaces, supplementing the support already provided by the frame. This results in rigid support for the filter bellows and suppresses any vibrations or oscillations. Furthermore, this arrangement ensures that the pleats are spaced correctly.

[0019] According to a further advantageous embodiment, the bridge can also be arranged parallel to the folds. In such an arrangement, the bridge can extend into a fold of the filter bellows and be connected to two adjacent folds across their entire surface by bonding, casting, or injection molding the bridge to these fold surfaces. This also effectively supports the filter bellows and stabilizes it against vibrations or pressure loads from the fluid being filtered.

[0020] According to an advantageous embodiment, the frame and / or the bridge can be formed by overmolding the filter bellows with a plastic. Manufacturing the frame and / or bridge in an injection molding machine ensures a favorable connection between the filter bellows, frame, and / or bridge. This creates a very strong and durable bond between the filter bellows, frame, and bridge components. Furthermore, overmolding is also an economically advantageous method for establishing a strong connection between the filter bellows, frame, and bridge.

[0021] According to a further advantageous embodiment, the end faces of the filter bellows can be injection-molded into the frame. This integration of the filter bellows' end faces offers the advantage of mechanically supporting, stabilizing, and holding the filter bellows in place, while simultaneously providing a favorable seal between the filter bellows and the frame. This seal is also effective within the filter system itself when the filter element is installed in a sealed manner. Furthermore, this design effectively protects the filter bellows against mechanical damage.

[0022] According to the invention, the bridge is integrally connected to the frame. Manufacturing the frame and bridge together, for example in an injection molding process, represents a very cost-effective and efficient method for permanently joining the two. This also achieves favorable mechanical stability of the frame through stiffening via the bridge. Additionally, it provides a convenient connection between the filter bellows and both the frame and the bridge, permanently joining the components into a single assembly.

[0023] Furthermore, according to the invention, the bridge features a removal handle. Removal should be relatively easy even if the filter element is stuck in the filter housing. The removal handle can have a knurled surface for a secure grip on the filter element. Alternatively, eyelets can be provided. It is also advantageous to ensure that the clean side cannot be contaminated by any dirt remaining on the filter element from the fluid filtration process. All these aspects can be easily addressed by attaching a removal handle to the bridge. The bridge provides a mechanically stable base for attaching a removal handle, allowing sufficient force to be applied even if the filter element is stuck.

[0024] According to a further advantageous embodiment, a seal can be arranged on one end face of the frame. Such a seal allows the filter element to be sealed when installed in a filter system, thus ensuring a reliable and permanent separation between the raw and clean sides of the filter system. The frame also provides a simple and reliable mounting option for the seal, facilitating easy installation of the seal in the filter element and simultaneously reducing the risk of damage to the seal during installation of the filter element in a filter system.

[0025] According to a further aspect, the invention relates to a filter system for filtering a fluid with a filter element according to the invention, wherein the filter element is arranged interchangeably in a filter housing of the filter system. The filter element comprises a filter bellows and a frame extending along the end faces of the filter bellows, the frame being open to a raw side and a clean side of the filter element to allow fluid flow. The frame of the filter element ensures reliable installation and removal of the filter element during maintenance. Furthermore, it enables a permanent seal of the filter element within the filter housing for reliable separation of the raw and clean sides of the filter system. Additionally, the frame provides stabilization and mechanical protection for the filter bellows during installation and removal from the filter housing.

[0026] The filter bellows is firmly connected to the frame, which has a transverse rib extending between two opposing side surfaces. The filter element according to the invention thus combines effective pleat support with a stable removal tab, enabling removal from a filter system even when the filter element is stuck. This is achieved by means of the rib, which is firmly connected to the surrounding frame, for example, made of plastic, in which the filter bellows is embedded. The rib also adheres to the pleats of the filter bellows. The pleats are stabilized, and the filter element can be reliably removed from a filter housing, for example, using a tab located on the rib. No parts can reach the clean side of the filter system, and damage to the filter bellows by the removal aid, such as a tab, is avoided.

[0027] The bridge is firmly connected to the filter bellows. In this way, the bridge can stabilize the filter bellows along its entire depth of the folds, for example, by being connected, glued, or embedded across the entire surface of two adjacent folds. Even if the bridge is only connected at the base of the folds, this results in advantageous stabilization, offering benefits compared to a bridge connected only at an upper edge and significantly better stabilization than an unconnected filter bellows.

[0028] According to another aspect, the invention relates to a use of the filter system for fuel filtration of an internal combustion engine with raw-side water separation. Brief description of the drawings

[0029] Further advantages become apparent from the following description of the drawings. The drawings illustrate exemplary embodiments of the invention. The drawings, the description, and the claims contain numerous features in combination. A person skilled in the art will expediently consider the features individually and combine them into meaningful further combinations.

[0030] They show, for example: Fig. 1 an isometric representation of a filter element with a frame and a bridge connected thereto according to an embodiment of the invention; Fig. 2 a longitudinal section through a filter element according to Fig. 1; Fig. 3 a top view of a filter element according to Fig. 1; Fig. 4. A detailed section through a filter element after Fig. 1 with a focus on the connection of the filter bellows to the frame; Fig. 5. a detailed section through a filter element after Fig. 1 with a focus on the installation of the seal in the frame; Fig. 6 an isometric representation of a filter system according to an embodiment of the invention with the housing top removed; and Fig. 7 an isometric representation of a filter system according to an embodiment of the invention with a section through the filter system and filter element; Embodiments of the invention

[0031] In the figures, identical or similar components are numbered with the same reference symbols. The figures merely show examples and are not to be understood as limiting.

[0032] Fig. Figure 1 shows an isometric view of a filter element 10 with a frame 28 and an associated web 30 according to an embodiment of the invention. The filter element 10 for filtering a fluid comprises a filter bellows 12 with a designated raw side 52 and a designated clean side 50 opposite it. The filter bellows 12 consists of a filter medium 14, which is folded in a zigzag pattern into folds 34 along fold edges 26, each extending between opposite end faces 22a, 22b of the filter bellows 12, and which has end face surfaces 20a, 20b running parallel to each other on opposite end faces 18, 19 and end faces 24a, 24b on end faces 16, 17 lying transversely to them. The folds 34 of the filter bellows 12 are not shown over the full length of the filter bellows, but are only indicated schematically over part of the length.

[0033] The filter element 10 further comprises a frame 28 extending along the end faces 16, 17, 18, 19, the frame 28 being open to the raw side 52 and the clean side 50 to allow fluid flow. The filter bellows 12 is rigidly connected to the frame 28. The frame 28 has a transverse web 30 extending between two opposing side faces 32a, 32b of the frame 28 and rigidly connected to the filter bellows 12. The web 30 is arranged transversely to the folds 34. Alternatively, the web 30 could also be arranged parallel to the folds 34. The frame 28 and the web 30 are formed by overmolding the filter bellows 12 with a plastic. The web 30 is thus integrally connected to the frame 28. Furthermore, the bridge 30 has a removal handle 36 with which the filter element 10 can be inserted into and removed from a filter system.A circumferential seal 40 is arranged on a lower end face 38 of the frame 28, with which the filter element 10 can be sealed when inserted into a filter housing.

[0034] In Fig. 2 is a longitudinal section through a filter element 10 according to Fig. Figure 1 shows the filter element 10 in section along the web 30. The filter bellows 12 is not shown across its entire width with its individual folds, but only over a portion of the width. The filter bellows 12 does not extend over the full height of the frame 28; a lower area on the raw side 52 of the frame 28 remains free. The web 30 has a depth 31 corresponding to the fold depth 42 of the filter bellows 12, so that, since it is connected to the filter bellows 12, the web 30 can support and stabilize it across its entire fold depth. Advantageously, the web 30, together with the frame 28, is represented by overmolding with plastic and thus connected to the filter bellows 12. The end faces 24a, 24b of the filter bellows 12 are also injected into the frame 28, which ensures a permanent and reliable connection to the frame 28.In this way, the filter bellows 12 is reliably sealed not only at the end faces 20a, 20b, but also at the end faces 24a, 24b by the frame 28. The removal handle 36 is formed by an upward projection of the web 30 and may have a grip recess 32 for easier handling and a firm grip when lifting the filter element 10. The flow direction 54 of the filter element 10 with the fluid from a bottom raw side 52 to a top clean side 50 is indicated by an arrow.

[0035] Fig. Figure 3 shows a top view of a filter element 10 after Fig. 1. The filter bellows 12 is again shown only along a portion of its length. The surrounding frame 28 encompasses the filter bellows 12, which is embedded within the frame 12, and has a web 30 that extends from one side surface 32a to the opposite side surface 32b, thus dividing the cross-sectional area of ​​the frame 28. The web 30 is arranged transversely to the folds 34 and the fold edges 26 of the filter bellows 12 and stabilizes the filter bellows 12 across its width. Alternatively, it is also conceivable to use two filter bellows 12, which are embedded in the frame 28 on both sides of the web 30.

[0036] Fig. Figure 4 shows a detailed section through a filter element 10. Fig. 1 with a focus on the connection of the filter bellows 12 to the frame 28. In Fig. Figure 4 shows that the end face 24b of the last fold 34 of the filter bellows 12 is embedded in the side face 32b of the frame 28, which is expediently achieved by overmolding the filter bellows 12 with the plastic of the frame 28. In this way, a firm and reliable connection of the filter bellows 12 to the frame 28, along with a permanent seal of the filter bellows 12, is ensured. The flow direction 54 of the filter element 10 with the fluid from a bottom raw side 52 to a top clean side 50 is indicated by an arrow.

[0037] In Fig. 5 is another detailed section through a filter element 10 after Fig. Figure 1 focuses on the attachment of the seal 40 in the frame 28. A circumferential seal 40 is attached to the lower end face 38 of the side surfaces 32a, 32b, as well as to the transversely arranged side surfaces of the frame 28. This seal engages in a groove in the side surfaces 32a, 32b. The seal 40 can be manufactured by injection molding, for example, in a two-component process. Alternatively, the seal 40 can be manufactured as a molded seal and then pressed into the groove. Another possibility is to overmold or cast the seal together with the filter bellows 12. The seal 40 is thus securely attached to the frame 28 and seals the filter element 10 in a filter housing 108, as shown in Figure 1. Fig. 7 shown, reliably.

[0038] Fig. Figure 6 shows an isometric representation of a filter system 100 according to an embodiment of the invention with the upper housing part 112 removed. The illustrated filter system 100 is typically suitable for fuel filtration of an internal combustion engine with pipe-side water separation.

[0039] The filter element 10 used in the filter system 100 is interchangeably arranged in a filter housing 108 of the filter system 100 and comprises a filter bellows 12 and a frame 28 extending longitudinally from end faces 16, 17, 18, 19 of the filter bellows 12. The frame 28 is open to a raw side 52 and a clean side 50 of the filter element 10 to allow fluid flow. The filter bellows 12 is rigidly connected to the frame 28. The frame 28 has a transverse web 30 extending between two opposing side faces 32a, 32b of the frame 28. The web 30 is also rigidly connected to the filter bellows 12 and additionally has a removal handle 36 with which the filter element 10 can be inserted into and removed from the filter housing 108.

[0040] In Fig.Figure 7 shows an isometric view of a filter system 100 according to an embodiment of the invention, with a section through the filter system 100 and filter element 10. The filter element 10 is located in the lower housing part 114, is fixed in the lower housing part 114, and can thus be permeated from below, from the raw side 52 upwards to the clean side 50, by the fluid to be filtered. The flow direction 54 through the filter element 10 with the fluid from the raw side 52 at the bottom to the clean side 50 at the top is indicated by an arrow. The area of ​​the filter bellows 12 of the filter element 10 is sealed against an external space of the filter housing 108 by means of the seal 40 arranged on the lower end face 38 of the frame 28.

[0041] The filter element 10 can be removed from the lower housing part 114 after removing the upper housing part 112.

Claims

[1] Filter element (10) for filtering a fluid comprising - at least one filter bellows (12) with a designated raw side (52) and a designated clean side (50) opposite it, made of a filter medium (14) which is folded in a zigzag pattern into folds (34) along fold edges (26) which extend between opposite end faces (22a, 22b) of the filter bellows (12), and which has end face surfaces (20a, 20b) running parallel to each other on opposite end faces (18, 19) and end faces (24a, 24b) on end faces (16, 17) lying transversely to them, - a frame (28) extending along the end faces (16, 17, 18, 19), wherein the frame (28) is open to the raw side (52) and to the clean side (50) to allow the fluid to flow through it, wherein the filter bellows (12) is rigidly connected to the frame (28), and wherein the frame (28) has a transverse web (30) extending between two opposing side faces (32a, 32b) of the frame (28) and is rigidly connected to the filter bellows (12), wherein the web (30) is integrally connected to the frame (28), characterized by that the bridge (30) has a removal handle (36). [2] Filter element according to claim 1, wherein the bridge (30) has at least a depth (31) corresponding to a fold depth (42) of the filter bellows (12). [3] Filter element according to claim 1 or 2, wherein the bridge (30) is arranged transversely to the folds (34). [4] Filter element according to one of claims 1 or 2, wherein the bridge (30) is arranged parallel to the folds (34). [5] Filter element according to one of the preceding claims, wherein the frame (28) and / or the bridge (30) is formed by overmolding the filter bellows (12) with a plastic. [6] Filter element according to one of the preceding claims, wherein the end faces (24a, 24b) of the filter bellows (12) are injected into the frame (28). [7] Filter element according to one of the preceding claims, wherein a seal (40) is arranged on an end face (38) of the frame (28). [8] Filter system (100) for filtering a fluid with a filter element (10) according to one of the preceding claims, wherein the filter element (10) is arranged interchangeably in a filter housing (108) of the filter system. [9] Use of the filter system (100) according to claim 8 for fuel filtration of an internal combustion engine with raw-side water separation.

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