Filter element and filter system

Abstract

The invention relates to a filter element (10) having a filter bellows (30) made of a filter medium (20) which is placed in the filter bellows (30) along fold edges (50), in particular in a zigzag manner, in folds (46) which each extend between opposite end edges (36, 38) of the filter bellows (30). The folded bellows (30) itself is arranged in a closed manner about a longitudinal axis (70) and encloses a cavity and is sealed on both end faces (12, 14) of the folded bellows in each case with end discs (16, 18). According to the invention, the filter bellows (30) has a cut edge on at least one of the end edge surfaces (40, 41) thereof such that at least one region (48) is formed by a fold (46) having a shortened fold length, the fold length of which is substantially the same at least in sections over the outer circumference (62) and the inner circumference (64) of the filter bellows (30). The invention also relates to a filter system (100) having such a filter element (10).

Description

Technical Field

[0001] The present invention relates to a filter element and a filtration system for drawing air, particularly for internal combustion engines, especially motor vehicles. Background Technology

[0002] DE 102014016908 discloses a circular filter element in which the end facets of the circular filter element are beveled relative to the longitudinal axis of the circular filter element in a semi-circular region of the end facets to reduce the filtration area. Filter bellows are arranged on correspondingly matched beveled support tubes. The beveled end facets on the element provide a defined orientation of the filter bellows within the filter housing. Summary of the Invention

[0003] One object of the present invention is to provide a filter element that can be installed in a filter housing in a way that prevents confusion and that provides the largest possible filtration area.

[0004] Another objective of this invention is to provide a filtration system having such filter elements.

[0005] According to one aspect of the invention, the above-mentioned task is achieved by a filter element with a circular filter bellows, which is composed of a filter medium having a circular or elliptical cross-section, the filter medium being placed in folds along folded edges in the filter bellows, the folds extending between opposing end edges of the filter bellows, wherein the folded bellows are arranged around a longitudinal axis in a self-closing manner and surround a cavity and are sealed at both ends by end plates, wherein the filter bellows has a beschnitt on at least one of its end edge faces such that at least one region is formed by folds with shortened fold lengths, the fold lengths of which are substantially the same on the outer and inner circumferences of the filter bellows.

[0006] According to another aspect of the invention, this task is achieved by a filtration system having a housing with an inlet and an outlet for fluid, and the housing having a first housing member and a second housing member, wherein a filter element is arranged in the housing, the filter element having a self-closing filter bellows arranged around a longitudinal axis, the filter bellows being sealed at its two end sides by end discs, wherein the filter bellows has a truncated edge in at least one of its end face surfaces such that at least one region is formed by a fold with a shortened fold length, the fold length of the fold being substantially the same at least segmentally at the outer and inner peripheries of the filter bellows, and wherein at least one of the housing members has at least one region constructed corresponding to the truncated edge of the filter element.

[0007] The advantageous design and benefits of the present invention are derived from the other claims, the description and the drawings.

[0008] A filter element is proposed, comprising a filter bellows made of filter media, which is positioned in folds, particularly serrated ones, along folded edges within the bellows, the folds extending between opposing end edges of the bellows. The folded bellows are arranged closedly around a longitudinal axis and surround a cavity, and are sealed at both ends by end plates. The filter bellows has a tangential edge in at least one of its end edge faces, thereby forming at least one region with folds having shortened fold lengths, the fold lengths of which are substantially the same, at least segmentally, on the outer and inner circumferences of the filter bellows.

[0009] The cut edge can be located on one end of the filter bellows or on both sides. The fact that the fold length is the same both externally and internally within the shortened fold length region means that the angle between the longitudinal axis of the filter element and the fold edge is essentially a right angle within the shortened fold length region. Optionally, within this region, a portion of the fold can have an end edge arranged obliquely to the longitudinal axis. For example, the end edge can be oriented perpendicular to the longitudinal axis at its edge within the region and beveled in the middle.

[0010] Advantageously, one or more areas with folds of shortened fold lengths can be provided, so that only a small portion of the filter surface is eliminated by the relatively short longitudinal extension of the filter bellows. Particularly advantageously, the intermediate tube can remain unchanged, so that the filter element can be supported over its entire longitudinal extension. Preferably, less than 50% of the end face of the filter bellows has folds with shortened fold lengths.

[0011] The filter bellows can preferably be trimmed before or after the folds are created by means of laser trimming.

[0012] In the context of this invention, end folds are two outward folds located at opposite end sides of the filter bellows. End edges are two free edges of the filter medium that extend along the end folds and are confined at the end sides of the filter bellows. End edges of the filter bellows are two additional free edges that extend between the end edges and according to the folding of the filter bellows. Folding edges are the edges along which the filter medium folds. In commercially known serrated, generally square filter bellows, the end edges and folding edges are typically straight and extend parallel to each other. Viewed from the side, the end edges of the filter bellows extend serratedly and perpendicular to the end edges and folding edges. Before the folding of the filter medium, the end edges of the filter bellows, subsequently having a generally square imaginary envelope (Umhüllende), extend straight and parallel to each other. The imaginary envelope is formed by the end edges, adjacent to the folded edges or end edges on the net fluid side of the filter bellows and adjacent to the folded edges or end edges on the original fluid side.

[0013] In the case of a filter bellows for a circular filter element, the filter media are closed, meaning their end folds are connected to each other. The filter bellows of a circular filter element can have a circular cross-section, but it can also have other closed cross-sectional shapes, such as an elliptical cross-section.

[0014] Advantageously, the closed end plate may have support ribs that support the filter element relative to the housing. These support ribs may be provided on the flat end face of the end plate. Alternatively, this support may be provided by providing support elements in notches. This allows for a reduction in the structural height of the filter element. If necessary, corresponding mating elements for supporting the elements may be arranged in the notches of the filter element within the corresponding housing component.

[0015] According to an advantageous design, in the region of the folded portion with a shortened fold length, the end edge of the folded portion lies in a flat surface. Preferably, the end edge of the folded portion with the shortened fold length can be located in a recess with a flat bottom in the filter bellows, originating from the end edge surface. This geometry can be easily manufactured.

[0016] According to an advantageous design, in the region of the folded portion with a shortened fold length, the end edge of the fold is located in a curved surface. Preferably, the end edge of the folded portion with the shortened fold length is located in a concave recess in the filter bellows, originating from the end edge surface. The recess or concave portion is referred to as concave, extending from the normally flat end face of the filter bellows into the filter bellows such that the end face formed by the serrated course of the end edge is partially retracted. The recess can be rounded or angular, such as semicircular, polygonal, quadrilateral, trapezoidal, or triangular. The recess can, for example, have an associated shape that produces an outcrop (herausgebissen) block in the filter bellows, i.e., an outcrop-like (ausbissartig) shape. The geometry of one or more recesses can be selected as needed. In particular, laser cutting allows for a greater degree of freedom when creating recesses in the filter bellows.

[0017] According to an advantageous design, recesses with folds having shortened fold lengths and folds having unshortened fold lengths alternately follow each other in the filter bellows. This allows for positional orientation and confusion-free installation when fitted into the filter housing of the filtration system, in order to prevent misalignment during assembly.

[0018] The housing cover can be constructed to correspond accordingly with the recess. This allows for the advantageous arrangement of locking elements between housing components, even in situations with limited structural space, which is common practice in the automotive industry.

[0019] According to an advantageous design, a unique recess can be arranged within the medium in the filter bellows, this recess having a folded portion with a shortened folded length. The design of the filter bellows can be matched as needed.

[0020] According to one of the patented designs, the filter bellows may have an annular cross-section. Alternatively, the filter bellows may have an elliptical cross-section or other cross-sections.

[0021] According to another aspect of the invention, a filtration system is proposed, particularly for a filter element according to the invention, comprising a housing having an inlet and an outlet for fluid, particularly for fluid in an internal combustion engine of a motor vehicle, and the housing having a first housing member and a second housing member, wherein the filter element is arranged in the housing, the filtration system further comprising a filter bellows made of filter media placed in folds along folded edges, particularly serrated, within the filter bellows, the folds extending between opposing end edges of the filter bellows. The folded bellows itself is arranged closedly around a longitudinal axis and surrounds a cavity and is sealed at its two end sides by end plates. The filter bellows has a tangent in at least one of its end edge faces, thereby forming at least one region by folds having shortened fold lengths substantially the same on the outer and inner circumferences of the filter bellows. At least one of the housing members has at least one region having a corresponding recess toward the tangent of the filter element.

[0022] For example, a corresponding design of a housing cover, for instance, that can be arranged on the end side of a filter element with slits, allows a notch to be constructed in the housing cover, forming a protrusion on its inner side, which can be inserted into a notch in the filter element. The filter element and the housing cover can then be correctly positioned relative to each other. Furthermore, the notch can be used to accommodate a locking element, allowing it to operate comfortably even in confined structural spaces. Additionally, the locking element, in the closed state of the filter housing, advantageously has little or no additional envelope extending beyond the filter housing. Advantageously, the end plate matches the structure at the end side of the filter element. This is particularly advantageously achieved using a foamed polymer, especially polyurethane, as the end plate material.

[0023] According to an advantageous design, the filter element can be arranged around a support tube having a constant axial extension along its circumference. In particular, the support tube can be constructed without shortening in areas with shortened folded lengths. Advantageously, complete support of the central region of the filter element can be ensured entirely by a continuous support tube.

[0024] According to an advantageous design, the cut edge can be arranged at the end of a filter element with a closed end plate. Alternatively or additionally, the cut edge can be arranged at the end of a filter element with an open end plate. This allows for a degree of design freedom to meet specific requirements.

[0025] The open end disc has a preferably coaxial flow opening, which is preferably used as an outlet opening. More preferably, the open end disc has a seal, preferably a radial seal and alternatively an axial seal, in the region of the flow opening for a sealing connection with an outlet on the housing side. The seal is preferably constructed as a single piece with the end disc, for example, by casting polyurethane.

[0026] According to an advantageous design, in the housing member facing the cut-off end of the filter element, at least one protrusion is embedded in at least one recess on the inner side of the housing member into the filter element. This allows for simple positional orientation between the housing member and the filter element. The housing member is preferably a housing cover and / or a housing bottom.

[0027] According to an advantageous design, the locking element, particularly a hook or wire clamp, can be arranged in a recess on the outer side of the housing, which forms a corresponding inner protrusion. Specifically, the locking element can be substantially recessed into the recess when the housing is closed. Advantageously, the pivotable element of the locking element can be positioned within the recess, where it is arranged in a space-saving and easily accessible manner.

[0028] According to an advantageous design, the dividing plane between the first and second housing members is arranged substantially at the axial height of the recess in the filter element. This allows easy access to the housing cover even in confined structural spaces.

[0029] The filtration system is, for example, an air filtration system, particularly an air filtration system for an internal combustion engine, preferably an air filtration system for an internal combustion engine in a motor vehicle. Alternatively, the filtration system is a liquid filtration system for a liquid fluid (e.g., oil or fuel), particularly a liquid filtration system for an internal combustion engine, preferably a liquid filtration system for an internal combustion engine in a motor vehicle. Attached Figure Description

[0030] Other advantages are illustrated in the following figures. Embodiments of the invention are shown in the figures. The figures, description, and claims contain a large number of combinations of features. Those skilled in the art can also suitably consider these features individually and conclude other meaningful combinations. Exemplary examples are shown below: Figure 1 An isometric view of a filtration system with filter elements according to an embodiment of the present invention is shown; Figure 2 Shown in exploded view Figure 1 Filtration system; Figure 3 Shown in top view Figure 1 Filtration system; Figure 4 Along Figure 3 The longitudinal section view of the cutting plane IV-IV in the figure shows Figure 1 The filtration system in the middle; Figure 5 In accordance with Figure 4 A magnified view of detail V in the image. Figure 1 A portion of the filtration system; Figure 6 Shown in isometric view Figure 1 Filter elements; Figure 7 An isometric view of a filter bellows according to an embodiment of the present invention is shown; Figure 8 Show Figure 7 A magnified view of a section of the filter bellows; Figure 9 Show in unfolded diagram Figure 7 The filter bellows in the middle; Figure 10 An isometric view of a filter bellows according to another embodiment of the present invention is shown; Figure 11 Show Figure 10 A magnified view of a portion of the filter bellows; Figure 12 Show in unfolded diagram Figure 10 Filter bellows; Figure 13 An isometric view of a filter bellows according to another embodiment of the invention is shown, which has an elliptical cross-section and a recess in the side region with a small curvature. Figure 14 Show Figure 13 Side view of the filter bellows; Figure 15 An isometric view of a filter bellows according to another embodiment of the invention is shown, which has an elliptical cross-section and a recess in a side region with significant curvature. Figure 16 It shows Figure 15 A side view of a filter element, which has an elliptical filter bellows. Detailed Implementation

[0031] In the accompanying drawings, the same or similar components are indicated by the same reference numerals. The drawings are merely illustrative and should not be construed as limiting.

[0032] Figures 1 to 6 Different views of a filtration system 100 having a filter element 10 according to an embodiment of the present invention are shown. Figure 1 An isometric view of the filtration system 100 is shown. Figure 2An exploded view of the filtration system 100 is shown. Figure 3 A top view of the filtration system 100 is shown. Figure 4 A longitudinal sectional view of the filtration system 100 is shown. Figure 5 A partial enlarged view of the filtration system 100 is shown, and Figure 6 An isometric view of filter element 10 is shown.

[0033] The filtration system 100 includes a housing 102 in which a cylindrical filter element 10 is arranged. The housing 102 includes a first housing member 104, such as a housing cover, and a second housing member 106, such as a housing tank. An inlet 108 for fluid is arranged, for example, tangentially, on the second housing member 106. Figure 3 And, for example, concentrically arranged outlets 110. In this embodiment, the flow of fluid through the filter element 10 proceeds in the radial direction from the outer periphery 62 corresponding to the inflow side 62 to the inner periphery 64 corresponding to the outflow side.

[0034] The filter element 10, arranged in the housing 102, consists of a filter bellows 30, which is composed of a filter medium 20. This filter medium is positioned within the folds of the filter bellows 30, particularly in a serrated manner, along the folded edges. The folded bellows 30 itself is arranged in a closed configuration around the longitudinal axis 70 and surrounds the support tube 26. The two end sides 12 and 14 are sealed using end plates 16 and 18, respectively. Figure 4 The end plate 16 facing the first housing member 104 is constructed in a closed manner at the end side 12 and is arranged on the side of the housing 102 away from the concentric outlet 110.

[0035] The dividing plane 124 between the first and second housing members 104, 106 is arranged substantially at the axial height of the end plate 18 of the filter element 10, which has a region 48 on its end side 12 with a recess 44 in the filter bellows 30. The locking element 130 for connecting the first housing member 104 to the second housing member 106 can then be easily reached by the operator.

[0036] The recess 44 in the filter bellows 30 of the filter element 10 forms the end edge 36 of the fold 46 in the filter bellows 30. Figure 7 , 8 The retracted portion in the direction of the longitudinal axis 70. The support tube 26 extends throughout its entire axial length inside the filter bellows 30 and is inserted into the end plates 16 and 18 at the end sides 12 and 14.

[0037] The recess 44 is complementary in shape to the end plate 16, which is preferably made of PUR foam. In this embodiment, the end edge of the fold 46 of the filter bellows 30 lies in a flat surface 42 within the recess 44. Support ribs 24, 28 are also arranged at the end face 22 of the end plate 16, as at the opposite end plate 18, by means of which the filter element 10 can be axially clamped between the two housing members 104, 106 in a conventional manner. For example, four equidistant recesses 44 are arranged on the filter element 10.

[0038] Alternatively, in an embodiment not shown in the figures, the support element may be arranged on the end plate 16 in the region of notch 44. For this purpose, a support surface may additionally be arranged on a protrusion on the corresponding housing member 104.

[0039] Depending on the arrangement of the recess 44 in the filter element 10, the second housing member 104 has a corresponding recess 120 when viewed from the outside. Viewed from the inside of the housing member 104, the recess 120 forms a protrusion 122 that is embedded in the recess 44. Here, a free space is maintained between the protrusion 122 in the first housing member and the recess 44 in the filter element 10.

[0040] A locking element 130 is arranged in a recess 120 on the outer side of the first housing member 104. This locking element can be configured as a wire clamp locking element. The movable part of the locking element 130, in this case, the swingable clamp, is recessed into the recess 120 in a space-saving manner when the housing 102 is closed, and the clamp is fixed to a mating element (not shown in detail) on the second housing member.

[0041] Figures 7 to 9 Different views of a filter bellows 30 according to one embodiment of the present invention are shown. Figure 7 An isometric view of the filter bellows 30 is shown. Figure 8 A magnified partial view of the filter bellows 30 is shown, and Figure 9 The filter bellows 30 is shown in an unfolded diagram.

[0042] The filter bellows 30 is formed by a filter medium 20 placed in a folded portion 46, the folded edge 50 of which extends between end edges 36 and 38. In its unfolded form, the filter bellows 30 has end folds 32 and 34 on both sides, the end folds being connected to each other to form a filter bellows 30 as a circular element with a closed cross-section. The fold 46 between the end edge faces 40 and 41 has a fold length L1. For simplicity, only some of the folded edges 50, end edges 36 and 38, and folds 46 are indicated by reference numerals.

[0043] In this embodiment of the invention, the filter bellows 30 has a cut edge at the end side, thereby forming four equidistant regions 48, wherein the fold 46 has a shortened fold length L2, wherein the fold length L2 on both sides of the filter medium 20 is the same or at least substantially the same as the inflow surface (outer perimeter 62) and the outflow surface (inner perimeter 64).

[0044] Region 48 has a rectangular recess 44. The cut edges of the filter bellows 30 are designed such that the end edges 36 of the fold 46 are oriented perpendicular to the longitudinal axis 70 of the filter bellows 30 in each region 48, that is, the angle α between the longitudinal axis 70 and the end edges 36 is 90°. The end edges 36 in region 48 terminate at a surface 42, which is flat and oriented perpendicular to the longitudinal axis 70.

[0045] Figures 10 to 12 Different views of a filter bellows 30 according to another embodiment of the present invention are shown. Figure 10 An isometric view of the filter bellows 30 is shown. Figure 11 A magnified partial view of the filter bellows 30 is shown, and Figure 12 The filter bellows 30 is shown in an unfolded diagram.

[0046] The structure of the filter bellows 30 corresponds to that in Figures 7 to 9 The structures in the embodiments are described herein to avoid unnecessary repetition.

[0047] Four equidistant regions 48 have concave recesses 44, where end edges 36 terminate in curved surfaces 43 within regions 48. These surfaces are cylindrical segments whose axis of symmetry is perpendicular to the longitudinal axis 70. The cut edges of the filter bellows 30 are designed such that the end edges 36 of the folds 46 are oriented perpendicular to the longitudinal axis 70 of the filter bellows 30 within regions 48; that is, the angle α between the longitudinal axis 70 and the end edges 36 is 90°. Due to the curvature of the surface 43, the length of the folds 46 in regions 48 varies, having a minimum fold length L2 at the minimum value of the notch 44.

[0048] Figure 13 and 14 A view of a filter bellows 30 according to another embodiment of the present invention is shown. Figure 13 An isometric view of the filter bellows 30 is shown, and Figure 14 A side view of the filter bellows 30 is shown.

[0049] The filter bellows 30 has an elliptical cross-section, in which a rectangular recess 44 is arranged in the side of the filter bellows 30, which has a small curvature. This cross-section is larger at one end of the filter bellows 30 than at the opposite end. Within the recess 44, a fold 46 has a shortened fold length L2. The end edge 36 of the fold 46 lies in a flat surface 42, wherein the end edge 36 is in the surface 42 and the surface 42 itself is oriented perpendicular to the longitudinal axis 70.

[0050] Figure 15 and Figure 16 A view of a filter bellows 30 according to another embodiment of the present invention is shown. Figure 15 An isometric view of the filter bellows 30 is shown, and Figure 16 A side view of it is shown.

[0051] The filter bellows 30 has an elliptical cross-section, with concave recesses 44 arranged in the sides of the filter bellows 30, which has a strong curvature. The cross-section is larger at one end of the filter bellows 30 than at the opposite end. Inside the recesses 44, folds 46 have shortened fold lengths that decrease from the end edge face 40 to a minimum at the center of the recesses 44. The end edge 36 of the folds 46 lies in a curved surface 43, wherein the end edge 36 is oriented perpendicular to the longitudinal axis 70 within the curved surface 43.

[0052] In all embodiments, it may be optionally specified that a segment of the end edge 36 has an angle α ≠ 90° (not shown) relative to the longitudinal axis 70 within one or more regions 48.

Claims

1. A filter element (10) having a circular filter bellows (30) composed of a filter medium (20), the filter medium being serratedly placed in folded portions (46) along folded edges (50) in the filter bellows (30), the folded portions extending between opposite end edges (36, 38) of the filter bellows (30). in, The folded bellows (30) is arranged in a closed manner around the longitudinal axis (70) and surrounds a cavity, and is sealed at both ends (12, 14) of the folded bellows with end plates (16, 18), wherein at least one of the end plates (16, 18) is constructed as an open end plate with a coaxial flow opening. The filter bellows (30) has a tang on at least one of its end face surfaces (40, 41), thereby forming at least one region (48) with a fold (46) having a shortened fold length. The fold length of the fold (46) is at least segmentally the same on the outer periphery (62) and inner periphery (64) of the filter bellows (30) in the region (48) with the fold (46) having a shortened fold length, wherein a recess (44) with a fold (46) having a shortened fold length and a fold (46) having an unshortened fold length alternately follow each other in the filter bellows (30).

2. The filter element according to claim 1, wherein, In the region (48) of the fold (46) with a shortened fold length, the end edges (36, 38) of the fold (46) are located in a flat surface (42), wherein the end edges (36, 38) of the fold (46) with a shortened fold length are located in a recess (44) with a flat bottom in the filter bellows (30) originating from the end edge surface (40).

3. The filter element according to claim 1 or 2, wherein, In the region (48) of the fold with shortened fold length, the end edges (36, 38) of the fold (46) are located in a curved surface (43), wherein the end edges (36, 38) of the fold with shortened fold length are located in a concave recess (44) in the filter bellows (30) originating from the end edge surface (40).

4. The filter element according to claim 1 or 2, wherein, In the filter bellows (30), there is a single recess (44) arranged within the medium (20), which has a fold (46) with a shortened fold length.

5. The filter element according to claim 1 or 2, wherein, The filter bellows (30) has an annular cross-section.

6. The filter element according to claim 1 or 2, wherein, The filter bellows (30) has an elliptical cross-section.

7. A filtration system (100) having a housing (102) having an inlet (108) and an outlet (110) for fluid of an internal combustion engine for a motor vehicle, and the housing having first and second housing parts (104, 106). in, A filter element (10) according to any one of claims 1 to 6 is arranged in the housing (102). At least one of the housing components (104) has at least one region (120) which is constructed corresponding to the cut edge of the filter element (10).

8. The filtration system according to claim 7, wherein, The filter element (10) is arranged around a support tube (26) having a constant axial extension along its circumference, and the support tube is constructed without shortening in a region (48) having a shortened fold length.

9. The filtration system according to claim 7 or 8, wherein, The cut edge is arranged on the end of the filter element (10) having a closed end plate (16).

10. The filtration system according to claim 7 or 8, wherein, The cut edge is arranged on the end of the filter element (10) having an open end plate (18).

11. The filtration system according to claim 7 or 8, wherein, In the housing (104) facing the cut-edge end (12) of the filter element (10), at least one protrusion (122) is embedded in at least one recess (44) on the inner side of the housing (104) of the filter element (10).

12. The filtration system according to claim 7 or 8, wherein, A locking element (130) is arranged in a recess (120) on the outer side that forms a corresponding inner protrusion (122), wherein the locking element (130) sinks into the recess (120) when the housing (102) is closed.

13. The filtration system according to claim 7 or 8, wherein, The separation plane (124) between the first and second housing parts (104, 106) is arranged at the axial height of the recess (44) in the filter element (10).

14. The filtration system according to claim 12, wherein, The locking element (130) refers to a hook.

15. The application of the filtration system according to any one of claims 7 to 14 as an air filter or a liquid filter.

16. The application of the filtration system according to any one of claims 7 to 14 as a circular filter for an internal combustion engine.

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