Filter element and filter system

Abstract

The invention relates to a filter element (10) for a filter system (100) for a fluid, in particular air, in particular from an internal combustion engine, which filter element comprises at least one filter-medium body (14) having a filter medium (12) which is folded substantially in the shape of a star. The filter-medium body (14) comprises, in at least one first angular segment (36) about the longitudinal axis (80), first folds (24) having outer fold edges (28) which lie in an outer cylindrical lateral surface (32), and having radially opposite inner fold edges (30) which lie in an inner cylindrical lateral surface (33) located on the inside of the outer cylindrical lateral surface (32) in the radial direction. The filter-medium body also comprises, at the same axial height in at least one second angular segment (38), second folds (25) having outer fold edges (28) which lie in the outer cylindrical lateral surface (32), and having radially opposite inner fold edges (30) which lie in a conical lateral surface (34) located on the inside of the outer cylindrical lateral surface (32) in the radial direction. The invention also relates to a filter system (100) comprising at least one filter element (10).

Description

[0001] Filter element and filter system

[0002] This patent application claims priority from German patent application No.

[0003] DE102023129009.6, filed with the German Patent and Trademark Office on October 23, 2023, the contents of which are hereby incorporated by reference.

[0004] Technical area

[0005] The invention relates to a filter element for a filter system for a fluid, in particular air, in particular of an internal combustion engine, and a filter system for a fluid, in particular air, in particular of an internal combustion engine, with at least one filter element.

[0006] State of the art

[0007] WO 0025893 discloses a filter system with a housing in which a round filter cartridge is installed. A component of the round filter cartridge is a filter medium made of a flat, foldable material, e.g., fleece or paper. The filter medium is folded such that the outer edges of the filter folds lie on a cylindrical surface. The inner folds of the filter medium form a conical interior space within the round filter cartridge. The outlet of the round filter cartridge is provided on the side where the interior space of the round filter cartridge has the larger diameter. The exterior, i.e., the installation volume of the round filter cartridge, has a cylindrical shape.

[0008] EP 3 156115 A1 describes a filter element for filtering a fluid, comprising a pleated filter body arranged around a longitudinal axis and having a closed periphery, wherein the filter body has folds extending along the longitudinal axis from a first end face to a second end face of the filter body. Inner fold edges of the folds form an inner shell, and outer fold edges of the folds form an outer shell of the filter body. At least one of the folds is divided into two or more folds along its longitudinal extent.

[0009] US 2017050137 A describes a cylindrical filter element with a filter medium body which has a flat area on an inner or outer diameter over the entire length.

[0010] EP 2535550 A2 discloses a cylindrical filter element with a filter medium body which has a groove on its outer surface over the entire length for rotationally secure assembly.

[0011] Disclosure of the invention

[0012] An object of the invention is to provide a filter element for a filter system for a fluid, in particular air, in particular of an internal combustion engine, which can be favorably coupled to a housing of the filter system.

[0013] A further object of the invention is to provide a filter system with such a filter element, which can be conveniently coupled to a housing of the filter system. According to one aspect of the invention, the aforementioned object is achieved with a filter element for a filter system for a fluid, in particular air, in particular of an internal combustion engine, comprising at least one filter medium body with a substantially star-shaped folded filter medium, which is arranged around a longitudinal axis and has a closed circumference, and with a first end face and a second end face opposite thereto, wherein the filter medium body has first folds in at least one first angular segment around the longitudinal axis with outer fold edges located in an outer cylinder surface, and with radially opposite inner fold edges located in an inner cylinder surface arranged radially within the outer cylinder surface.and at least in one region along the longitudinal axis at the same axial height in at least one second angular segment, second folds with outer fold edges lying in the outer cylinder surface, and with radially opposite inner fold edges lying in a conical surface arranged radially inside the outer cylinder surface, or at least in one axial region along the longitudinal axis at the same axial height in at least one second angular segment, second folds with inner fold edges lying in an inner cylinder surface, and with radially opposite outer fold edges lying in a conical surface arranged radially outside the inner cylinder surface.

[0014] According to a further aspect of the invention, the further object is achieved by a filter system for a fluid, in particular air, in particular of an internal combustion engine, with at least one filter element according to one of the preceding claims, comprising a housing with a first housing part and a second housing part, a fluid inlet arranged on the housing for supplying the fluid to be filtered, and a fluid outlet arranged on the housing for discharging the filtered fluid, wherein a coupling element of the housing engages in a longitudinal direction in at least a second angular segment of a filter medium body of the filter element with a conical jacket surface when the filter element is mounted as intended.

[0015] Advantageous embodiments and advantages of the invention emerge from the further claims, the description and the drawing.

[0016] According to one aspect of the invention, a filter element for a filter system for a fluid, in particular air, in particular of an internal combustion engine, is proposed, comprising at least one filter medium body with a substantially star-shaped folded filter medium, which is arranged around a longitudinal axis and has a closed circumference and with a first end face and a second end face opposite thereto. In at least one first angular segment around the longitudinal axis, the filter medium body has first folds with outer fold edges that lie in an outer cylinder surface, and with radially opposite inner fold edges that lie in an inner cylinder surface arranged in the radial direction within the outer cylinder surface.The filter medium body has, at least in one region along the longitudinal axis, at the same axial height in at least one second angular segment, second folds with outer fold edges that lie in the outer cylinder surface, and with radially opposite inner fold edges that lie in a conical surface arranged in the radial direction inside the outer cylinder surface. Alternatively, the filter body has, at least in one region along the longitudinal axis, at the same axial height in at least one second angular segment, second folds with inner fold edges that lie in an inner cylinder surface, and with radially opposite outer fold edges that lie in a conical surface arranged in the radial direction outside the inner cylinder surface.

[0017] The proposed filter element comprises a filter medium body with a star-shaped pleated filter medium, which has a closed circumference and is thus designed, for example, as a hollow cylinder. Alternatively, the filter medium body can be designed in a different shape that is closed around the longitudinal axis. In this case, the filter medium body has a cylindrical shape over at least a first part of its circumference, in a first angular segment around the longitudinal axis, and a so-called semi-conical shape over at least another part of its circumference, in a second angular segment around the longitudinal axis. The semi-conical shape of the filter medium body is achieved by additional folding between the first folds of the filter medium, so that the pleat height on one end face of the filter medium body corresponds to half the pleat height on the other end face of the filter medium body.In the region of the semi-conical shape, the fold edges of the second folds lie on a cylindrical outer surface, and radially opposite fold edges lie on a conical outer surface. The filter medium body can be designed in this way along its entire longitudinal extension. Alternatively, only a partial area along the longitudinal extension of the filter medium body can be designed in this way.

[0018] This creates an additional coupling option with a secondary element and / or with the filter system housing. This advantageously allows for directional installation of the filter element into the filter housing. Furthermore, anti-twist protection for the filter element can be implemented.

[0019] The second folds of the filter medium body can be created by folding each first fold again on one end face, creating a conical fold. In this way, the filter medium body can have, at least in one angular segment, a cylindrical outer surface and a conical inner surface, or a conical outer surface and a cylindrical inner surface.

[0020] Advantageously, angle segments with semi-conical and cylindrical shapes can be arranged alternately around the circumference of the filter medium body. The conical surface can be arranged on the outer or inner circumference. The filter element can be advantageously used in a single-stage or two-stage filter system with cyclone separation. Such filter systems are used, for example, in construction and agricultural machinery.

[0021] The alternating angular segments with semi-conical and cylindrical shape can be arranged on a secondary filter element, if present, or on a main filter element.

[0022] The semi-conical shape of the filter medium body, at least in some areas, promotes a larger flow cross-section and thus enables a lower pressure loss when flowing through the filter element.

[0023] According to a favorable embodiment of the filter element, in the at least one second angular segment with the conical surface, two or more second folds can be present in at least one of the first folds of the filter medium body along the longitudinal axis. In particular, in the at least one second angular segment, first folds can be present on the first end face and second folds can be present on the second end face. By dividing the first folds into two or more second folds, the fold height on this end face can be significantly reduced and thus the cone angle of the filter medium body can be increased. The second folds are inclined towards the longitudinal axis. For example, a first fold can be divided into two second folds. Optionally, a first fold can be divided into more than two second folds. Accordingly, the number of folds in the second angular segment increases compared to the first angular segment.

[0024] According to a favorable embodiment of the filter element, the pleat height of the second pleats in the at least one second angle segment can vary continuously along the longitudinal axis. The conical outer surface can be designed by forming additional pleats between the pleats of the filter medium, so that the pleat height on one end face of the filter medium body corresponds to half the pleat height on the other end face of the filter medium body.

[0025] According to a favorable embodiment of the filter element, the second pleats in the at least one second angle segment can have half the pleat height of the first pleats in the at least one first angle segment. The difference in pleat height can advantageously ensure angularly accurate and rotation-proof installation of the filter element in the housing of the filter system.

[0026] According to a favorable embodiment of the filter element, the filter medium body can have a support tube arranged in the interior, wherein the inner cylindrical surface of the filter medium body formed in the at least one first angular segment engages in a corresponding recess formed in the longitudinal direction of the support tube. In this way, an angularly accurate and twist-proof installation of the filter element in the housing of the filter system can be advantageously ensured. According to a favorable embodiment of the filter element, the first and second end faces of the filter medium body can each have an end plate. In particular, the first and second end faces of the filter medium body can be overmolded with a material of the end plate. The end plate ensures secure installation and sealing of the filter element in the housing of the filter system.

[0027] According to a favorable design of the filter element, the support tube can be embedded, in particular overmolded, into each end plate. This ensures a particularly secure and permanent connection between the support tube and the end plate.

[0028] According to a favorable design of the filter element, the end plates can have circumferential seals that protrude longitudinally. In particular, the seals can be integrated into the end plates. This allows for a reliable seal between the dirty and clean sides of the filter system housing.

[0029] According to a favorable design of the filter element, first angle segments and second angle segments can be arranged alternately on a circumference of the filter medium body. This ensures a rotation-proof installation of the filter element in the housing of the filter system. At the same time, this allows for coding the assignment of filter elements to filter systems.

[0030] According to a favorable design of the filter element, at least part of the outer cylindrical surface of the filter medium body can be covered with an inflow guard. This protects a sensitive filter medium from the pressure of the incoming fluid. Furthermore, coarse dirt particles can be pre-separated. This advantageously prevents the filter medium of the filter element from becoming contaminated by these dirt particles.

[0031] According to a further aspect of the invention, a filter system for a fluid, in particular air, in particular of an internal combustion engine, with at least one filter element is proposed, comprising a housing with a first housing part and a second housing part, a fluid inlet arranged on the housing for supplying the fluid to be filtered, and a fluid outlet arranged on the housing for discharging the filtered fluid. During proper assembly of the filter element, a coupling element of the housing engages in a longitudinal direction with at least a second angular segment of a filter medium body of the filter element having a conical outer surface.

[0032] The proposed filter system thus provides an additional coupling option between the filter element and the housing of the filter system. This enables directional installation of the filter element into the filter housing. Furthermore, it is advantageously possible to implement anti-twist protection for the filter element in the filter housing. The filter element comprises a filter medium body with a star-shaped folded filter medium that has a closed circumference and is thus designed, for example, as a hollow cylinder. Alternatively, the filter medium body can be designed in a different shape that is closed around the longitudinal axis. In this case, the filter medium body has a cylindrical shape at least over a first part of its circumference, in a first angular segment around the longitudinal axis, and a semi-conical shape over at least another part of its circumference, in a second angular segment around the longitudinal axis.The semi-conical shape of the filter medium body is achieved by additionally folding second pleats between the first pleats of the filter medium, so that the pleat height on one end of the filter medium body corresponds to half the pleat height on the other end of the filter medium body. In the semi-conical shape, the pleat edges of the second pleats lie on a cylindrical surface, and radially opposite pleat edges lie on a conical surface.

[0033] Advantageously, angular segments with semi-conical and cylindrical shapes can be arranged alternately around the circumference of the filter medium body. The conical surface can be arranged on the outer or inner circumference.

[0034] The filter element can be advantageously used in a single-stage or two-stage filter system with cyclone separation. Such filter systems are used, for example, in construction and agricultural machinery.

[0035] According to a favorable embodiment of the filter system, the coupling element can have a recess in the region of at least one first angular segment of the filter medium body with a cylindrical outer surface. This allows the filter element to be securely mounted in the filter housing at a fixed angular position around the longitudinal axis and can be reliably mounted in the filter housing in a rotationally secure manner.

[0036] According to a favorable embodiment of the filter system, the coupling element can be designed as a central tube fixed to the housing, which accommodates the filter element during proper installation. An inner cylindrical surface formed in at least one first angular segment can engage with a corresponding recess formed in the longitudinal direction of the central tube. This allows the filter element to be securely mounted in the filter housing at a fixed angular position around the longitudinal axis and can be reliably mounted in the filter housing in a rotationally secure manner.

[0037] Short description of the drawings

[0038] Further advantages will 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. Those skilled in the art will expediently consider the features individually and combine them into useful further combinations. The following are examples: Figure 1 shows a sectional view of a filter system for a fluid, in particular air, in particular of an internal combustion engine, with a filter element according to an exemplary embodiment of the invention;

[0039] Figure 2 is an isometric view of a filter element according to an embodiment of the invention;

[0040] Figure 3 is a sectional view of the filter element according to Figure 2;

[0041] Figure 4 is a schematic representation of the transition from first folds to second folds of the folded filter medium;

[0042] Figure 5 is a plan view of a first end face of the filter element according to Figure 2;

[0043] Figure 6 shows a view into the first housing part of the filter system according to Figure 1; and

[0044] Figure 7 is a sectional view through the filter system in section plane AA according to Figure 1.

[0045] Embodiments of the invention

[0046] In the figures, identical or similar components are numbered with the same reference numerals. The figures show only examples and are not to be understood as limiting.

[0047] To explain the invention, Figure 1 shows a sectional view of a filter system 100 for a fluid, in particular air, in particular of an internal combustion engine, with a filter element 10 according to an embodiment of the invention. Figure 2 shows an isometric view of the filter element 10, while Figure 3 shows a sectional view of the filter element 10.

[0048] The filter system 100 comprises a housing 110 with a first housing part 112 and a second housing part 114, a fluid inlet 102 arranged on the housing 110 for supplying the fluid to be filtered (visible in Figure 6), and a fluid outlet 104 arranged on the housing 110 for discharging the filtered fluid. Furthermore, the housing 110 has a dirt outlet 106 for discharging coarse dirt particles, which are separated, for example, in a cyclone pre-separator.

[0049] A filter element 10 is arranged in the housing 110.

[0050] The filter element 10 comprises a filter medium body 14 with a substantially star-shaped folded filter medium 12, which is arranged around a longitudinal axis 80 and has a closed circumference 40 and with a first end face 16 and a second end face 18 opposite thereto.

[0051] As can be seen in particular in Figure 3, the filter medium body 14 has, in at least one first angular segment 36 around the longitudinal axis 80, first folds 24 with outer fold edges 28, which lie in an outer cylinder surface 32, and radially opposite inner fold edges 30, which lie in an inner cylinder surface 33 arranged in the radial direction within the outer cylinder surface 32. Furthermore, the filter medium body 14 has, at the same axial height in at least one second angular segment 38, second folds 25 with outer fold edges 28, 31, which lie in the outer cylinder surface 32, and radially opposite inner fold edges 30, which lie in a conical surface 34 arranged in the radial direction within the outer cylinder surface 32.

[0052] Alternatively, the filter medium body 14 could also have, at the same axial height in at least one second angle segment 38, second folds 25 with inner fold edges 30 which lie in an inner cylinder surface 33, and radially opposite outer fold edges 28, 31 which lie in a conical surface 34 arranged in the radial direction outside the inner cylinder surface 33.

[0053] In the at least one second angular segment 38 with the conical surface 34, two or more second folds 25 are present in at least one of the first folds 24 of the filter medium body 14 along the longitudinal axis 80. The second folds 25 are inclined toward the longitudinal axis 80. In particular, in the at least one second angular segment 38, first folds 24 can be present on the first end face 16 and second folds 25 can be present on the second end face 18.

[0054] This can be seen in Figure 4, where a schematic representation of the transition from first folds 24 to second folds 25 of the folded filter medium 12 is shown.

[0055] A fold height 26 of the second folds 25 in the at least one second angle segment 38 changes continuously along the longitudinal axis 80. The second folds 25 in the at least one second angle segment 38 have half the fold height 27 of the fold height 26 of the first folds 24 in the at least one first angle segment 36.

[0056] In this embodiment, the number of second folds 25 is doubled compared to the number of first folds 24. The number of inner fold edges 30 is also multiplied accordingly.

[0057] As can be seen particularly in Figures 2 and 3, the filter medium body 14 has a support tube 42 arranged inside. The inner cylindrical surface 33 of the filter medium body 14 formed in the at least one first angle segment 36 engages in a corresponding recess 44 of the support tube 42 formed in the longitudinal direction 80.

[0058] The first and second end faces 16, 18 of the filter medium body 14 each have an end plate 20, 22. The first and second end faces 16, 18 of the filter medium body 14 are overmolded with a material of the end plate 20, 22. The support tube 42 is embedded in each end plate 20, 22 and can advantageously be overmolded with the material of the end plate 20, 22. The end plates 20, 22 have circumferential seals 21, 23 projecting in the longitudinal direction 80. The seals 21, 23 are integrated into the end plates. In an alternative embodiment, the filter element 10 can also have a plurality of first angle segments 36 and second angle segments 38, which can be arranged alternately on a circumference of the filter medium body 14.

[0059] Furthermore, at least a part of the outer cylinder surface 32 of the filter medium body 14 can be covered with a flow protection, not shown, which serves to protect the filter medium body 14 from coarse particles of the incoming fluid.

[0060] Figure 5 shows a plan view of the second end face 18 of the filter element 10 according to Figures 2 and 3. The end plate 22 with the circumferential seal 23 closes off the filter medium body 14 at the second end face 18. Inside the filter element, the first angular segment 36 of the filter medium body 14 with the cylindrical outer surfaces 32, 33 can be seen, as well as the second angular segment 38 with the conical outer surface 34 directed radially inward. Struts of the support tube 42 can also be seen. The first angular segment 36 of the filter medium body 14 is overmolded on the second end face 18 with the material of the end plate 22, as can also be seen in the section in Figure 3.

[0061] Figure 6 shows a view into the first housing part 112 of the filter system 100 according to Figure 1, while Figure 7 shows a sectional view through the filter system 100 in the section plane AA according to Figure 1.

[0062] When the filter element 10 is installed as intended in the housing 110 of the filter system 100, a coupling element 120 of the housing 110 of the filter system 100, which can be seen in section in Figure 1 and in plan view in Figure 6 as a circumferential ring, engages in a longitudinal direction 80 in the second angle segment 38 of a filter medium body 14 of the filter element 10 with a conical shell surface 34.

[0063] The coupling element 120 has, in the region of at least one first angle segment 36 of the filter medium body 14 with a cylinder surface 32, 33, a recess 122 into which the first angle segment 36 of the filter medium body 14 can engage.

[0064] In the sectional view in Figure 7 it can be seen how the inner cylinder surface 33 of the filter medium body 14 formed in the first angle segment 36 engages in the corresponding recess 44 of the support tube 42 formed in the longitudinal direction 80.

[0065] The interlocking of the first and second angle segments 36, 38 of the filter element 100 with the coupling element 120 and its recess 122 provides an advantageous coupling option for the filter element 10 to the housing 110 of the filter system 100. This advantageously enables directional installation into the filter housing 110. Furthermore, anti-twist protection of the filter element 10 can advantageously be implemented. This ensures anti-twist installation of the filter element 10 in the housing 110 of the filter system 100. The alternating arrangement of several first and second angle segments 36, 38 around the longitudinal axis 80 also advantageously enables coding of the assignment of filter elements 10 to filter systems 100.

[0066] In an alternative embodiment, the coupling element 120 can also be designed as a housing-fixed central tube 124, which accommodates the filter element 10 during proper assembly. In this case, an inner cylindrical surface 32 formed in at least one first angle segment 36 can engage in a corresponding recess 126 of the central tube 124 formed in the longitudinal direction 80. In the section in Figure 7, the support tube 42 could also represent this housing-fixed central tube 124 with the associated recess 126.

[0067] Reference symbol

[0068] 10 filter element

[0069] 12 Filter medium

[0070] 14 filter medium body

[0071] 16 Front side

[0072] 18 Front side

[0073] 20 end plate

[0074] 21 Seal

[0075] 22 End plate

[0076] 23 Seal

[0077] 24 first fold

[0078] 25 second fold

[0079] 26 pleat height

[0080] 27 fold height

[0081] 28 outer fold edge

[0082] 30 inner pleat edge

[0083] 31 outer fold edge

[0084] 32 outer cylinder surface

[0085] 33 inner cylinder surface

[0086] 34 Cone surface

[0087] 36 first angle segment

[0088] 38 second angle segment

[0089] 40 circumference

[0090] 42 support tube

[0091] 44 recess

[0092] 80 Longitudinal axis

[0093] 100 filter system

[0094] 102 Fluid inlet

[0095] 104 Fluid outlet

[0096] 106 Dirt outlet

[0097] 110 filter housings

[0098] 112 Housing part

[0099] 114 Housing part

[0100] 120 coupling element

[0101] 122 recess

[0102] 124 center pipe

[0103] 126 recess

Claims

Claims 1. Filter element (10) for a filter system (100) for a fluid, in particular air, in particular of an internal combustion engine, comprising at least one filter medium body (14) with a substantially star-shaped folded filter medium (12), which is arranged around a longitudinal axis (80) and has a closed circumference (40) and with a first end face (16) and a second end face (18) opposite thereto, wherein the filter medium body (14) has, in at least one first angular segment (36) around the longitudinal axis (80), first folds (24) with outer fold edges (28) lying in an outer cylinder surface (32), and with radially opposite inner fold edges (30) lying in an inner cylinder surface (33) arranged in the radial direction within the outer cylinder surface (32),and at least in one region along the longitudinal axis (80) at the same axial height in at least one second angular segment (38) has second folds (25) with outer fold edges (28, 31) that lie in the outer cylinder surface (32), and with radially opposite inner fold edges (30) that lie in a conical surface (34) arranged radially inside the outer cylinder surface (32), or at least in one region along the longitudinal axis (80) at the same axial height in at least one second angular segment (38) has second folds (25) with inner fold edges (30) that lie in an inner cylinder surface (33), and with radially opposite outer fold edges (28, 31) that lie in a conical surface (34) arranged radially outside the inner cylinder surface (33).

2. Filter element according to claim 1, wherein in the at least one second angle segment (38) with the conical surface (34) in at least one of the first folds (24) of the filter medium body (14) along the longitudinal axis (80) two or more of the second folds (25) are present, in particular wherein in the at least one second angle segment (38) on the first end face (16) first folds (24) are present and on the second end face (18) second folds (25) are present.

3. Filter element according to claim 1 or 2, wherein a pleat height (26) of the second pleats (25) in the at least one second angle segment (38) changes continuously along the longitudinal axis (80).

4. Filter element according to one of the preceding claims, wherein the second folds (25) in the at least one second angle segment (38) have half the fold height (27) of the fold height (26) of the first folds (24) in the at least one first angle segment (36).

5. Filter element according to one of the preceding claims, wherein the filter medium body (14) has a support tube (42) arranged in the interior, wherein the inner cylinder surface (33) of the filter medium body (14) formed in the at least one first angle segment (36) engages in a corresponding recess (44) of the support tube (42) formed in the longitudinal direction (80).

6. Filter element according to one of the preceding claims, wherein the first and the second end face (16, 18) of the filter medium body (14) each have an end plate (20, 22), in particular wherein the first and the second end face (16, 18) of the filter medium body (14) are overmolded with a material of the end plate (20, 22).

7. Filter element according to claim 6, wherein the support tube (42) is embedded, in particular overmolded, in each end plate (20, 22).

8. Filter element according to one of claims 6 or 7, wherein the end plates (20, 22) have circumferential seals (21, 23) projecting in the longitudinal direction (80), in particular wherein the seals (21, 23) are integrated into the end plates.

9. Filter element according to one of the preceding claims, wherein first angle segments (36) and second angle segments (38) are arranged alternately on a circumference of the filter medium body (14).

10. Filter element according to one of the preceding claims, wherein at least a part of the outer cylindrical surface (32) of the filter medium body (14) is covered with an inflow protection.

11. Filter system (100) for a fluid, in particular air, in particular of an internal combustion engine, with at least one filter element (10) according to one of the preceding claims, comprising - a housing (110) with a first housing part (112) and a second housing part (114), - a fluid inlet (102) arranged on the housing (110) for supplying the fluid to be filtered, - a fluid outlet (104) arranged on the housing (110) for discharging the filtered fluid, wherein a coupling element (120) of the housing (110) engages in a longitudinal direction (80) in at least one second angle segment (38) of a filter medium body (14) of the filter element (10) having a conical outer surface (34) when the filter element (10) is mounted as intended.

12. Filter system according to claim 11, wherein the coupling element (120) has a recess (122) in the region of at least one first angle segment (36) of the filter medium body (14) with a cylinder jacket surface (32, 33).

13. Filter system according to claim 11 or 12, wherein the coupling element (120) is designed as a central tube (124) fixed to the housing, which receives the filter element (10) when mounted as intended, wherein an inner cylinder surface (32) formed in at least one first angle segment (36) engages in a corresponding recess (126) formed in the longitudinal direction (80) of the central tube (124).

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