Air filter with a guiding device for supporting a filter element in a housing cover and filter housing

Abstract

air filter (10; 50; 52) having - a filter housing (12) with a housing pot (14) and a housing cover (16), and - a filter element (18; 54) designed as a hollow body with a filter medium (24; 60) and a support structure (28; 62 arranged on the inside of the filter medium (24; 60), which can be arranged in the filter housing (12), wherein the housing pot (14) has a guide device (38) which, when the filter element (18; 54) is inserted into the housing pot (14), extends into the filter element (18; 54) and can be brought into contact with the support structure (28; 62).

Description

Technical field

[0001] The invention relates to an air filter comprising a filter housing with a housing pot and a housing cover and at least one filter element with a filter medium and a support structure arranged on the inside of the filter medium, which can be arranged in the filter housing. State of the art

[0002] Such air filters are well known from the state of the art.

[0003] Especially with large air filters, for example for filtering combustion air for combustion engines of trucks, the filter element must be sufficiently supported in the filter housing.

[0004] EP 2 175 960 B1 shows the support of a filter element with a round, cylindrical or conical cross-section at its two end caps, wherein a housing pot or a housing cover each interacts with one of the two end caps.

[0005] EP 1 163 039 B1 discloses a filter with a pot-shaped housing and a round filter cartridge. The housing has a conical support tube without undercuts. Sealing areas of the end plates of the round filter cartridge rest on the outside of the support tube.

[0006] Particularly in horizontal arrangements, the installation of the filter element into the filter housing is often complicated by the fact that the filter element inserted into the housing bowl disengages from a sealing contour on the filter housing under the influence of gravity. Closing the housing bowl with the housing cover can also be complicated by the filter element sinking.

[0007] It is an object of the invention to simplify the replacement of a filter element in a filter housing. Disclosure of the invention

[0008] This object is achieved by an air filter having the features specified in claim 1 and a filter housing according to claim 15. Preferred embodiments are specified in the respective subclaims and the description.

[0009] According to the invention, an air filter is provided. The air filter has a filter housing with a housing bowl and a housing cover. An inlet for raw air to be filtered can be formed on the housing cover. An outlet for filtered clean air can be formed on the housing bowl. The air filter further has at least one (first) filter element designed as a hollow body with a filter medium and a support structure arranged on the inside of the filter medium. The filter medium can surround an interior of the filter element in a ring shape, in particular a circular ring or preferably oval. In other words, the filter element can have an oval cross-section. In addition to a completely curved contour, an oval cross-section is also to be understood, with two parallel sides and two opposite convex sides. The filter element can be conical.The support structure can be grid-shaped, in particular as a support tube. The filter element can be delimited at the front by end plates. The support structure can extend between the end plates. The filter element can be arranged in the filter housing. The filter element can separate a dirty side at the inlet from a clean side at the outlet. The air filter can be used in particular for filtering combustion air of an internal combustion engine, in particular of a truck.

[0010] Furthermore, according to the invention, the housing pot has a guide device which extends into the filter element when the filter element is inserted into the housing pot. In other words, the guide structure projects into the interior of the filter element when the filter element is installed. According to the invention, the guide structure can be brought into contact with the support structure of the filter element inserted into the housing pot. The contact of the support structure with the guide device can be established at least when the housing cover is removed. When the support structure and guide device are in contact with one another, the filter element is preferably inserted completely in the axial direction or in the depth direction into the housing pot. In particular, the filter element can at least partially contact a sealing contour of the housing pot, in particular with an end plate.

[0011] The guide structure thus prevents excessive tilting of the filter element in the housing bowl when the housing cover is removed. This facilitates installation and removal of the filter element into and from the housing bowl. The guide device can limit the inclination of the filter element relative to its operating position with the housing cover in place to a maximum of 20°, preferably a maximum of 10°. Furthermore, the guide device can guide the filter element to the sealing contour in the housing bowl during insertion. During removal, the guide device can prevent sudden movements of the filter element when it is lifted off the sealing contour.

[0012] Preferably, the support structure is lifted from the guide device when the housing cup is closed with the housing cover. The housing cover can engage the filter element to move it into an operating position. In the operating position, contact between the guide device and the support structure of the first filter element is eliminated. This allows for complete contact of the filter element, in particular an end plate of the filter element, with the sealing contour of the housing.

[0013] Particularly preferably, the guide device has a holding element for engaging in the support structure of the filter element. The holding element can be designed to engage behind a web of the support structure. The holding element can be designed as a projection, in particular as a hook, on the guide structure. In particular, it is provided that the holding element engages in the support structure or engages behind the web when the guide structure rests against the support structure. Even when the filter element is in the operating position, the holding element can engage in the support structure or engage behind the web. The holding element can particularly reliably prevent the filter element from spontaneously detaching from the housing pot when the housing cover is opened. During assembly, the holding element can hold the filter element in the housing pot until the housing cover is put on.In order to guide the filter element over the holding element, the filter element can be tilted in order to remove the support structure in the region of the holding element from the guide device. When the air filter is in use or when the housing pot is arranged in a position of use, the holding element is generally arranged at the top of the guide device. In particular, the holding element can protrude upwards. Conversely, the support structure can accordingly have a holding element, for example a projection, in particular a hook, for engaging in the guide device. For this purpose, the guide device can have a recess or a rib which can be engaged behind by the holding element.

[0014] The guide device can comprise at least one guide rib. The guide rib preferably extends between two opposing wall sections of the housing pot. Such a guide rib can effectively guide the filter element. At the same time, a noticeable impairment of the airflow through the air filter can be avoided.

[0015] The guide device advantageously has at least two spaced-apart guide ribs. The guiding effect can thereby be further improved. This embodiment is particularly suitable for filter elements with a non-circular cross-section, for example, oval filter elements. The at least two guide ribs can be congruent with one another. The guide ribs are preferably arranged offset from one another in parallel.

[0016] The guide ribs can be connected to each other by a cross rib. This increases the stability of the guide device.

[0017] Advantageously, the filter medium is pleated in a zigzag pattern, in particular formed from a zigzag-folded paper. This allows for an increased effective filter area while maintaining compact external dimensions.

[0018] If the air filter has only one (first) filter element, this is generally a main filter element.

[0019] The air filter can preferably further comprise a second filter element, which can be arranged in addition to the (first) filter element in the filter housing. The second filter element cannot be brought into contact with the guide device - at least when the (first) filter element is inserted into the housing pot. The second filter element can be a main filter element; the first filter element can be a secondary filter element. The effectiveness of the air filter can thereby be further increased. The first filter element can be arranged on the clean side of the second filter element. When replacing the second filter element, the first filter element can prevent dirt from entering the clean air outlet. In this case, the guide device thus represents an insertion aid for the secondary element.

[0020] The support structure of the (first) filter element is preferably lifted off the guide device when the second filter element is inserted into the housing pot and the housing pot is closed with the housing cover. This allows the first filter element, in particular an end plate of the first filter element, to fully engage the sealing contour of the housing. The housing cover can engage the second filter element in order to move it into its operating position. The second filter element can engage the first filter element in order to move it into its operating position. In the operating position, contact between the guide device and the support structure of the first filter element is eliminated. In the operating position, the filter elements can rest against one another.

[0021] The guide device can be located on the clean side. This allows the filter housing to be opened on the unfiltered side to replace the filter element(s). This reduces the risk of dirt entering the clean side.

[0022] When installed, the (first) filter element and / or the second filter element can engage around a horizontally extending axis, at least in the area of ​​the guide device. In other words, the filter element(s) can surround the horizontal axis in a ring-like manner. When the filter elements are aligned horizontally, the action of the guide device is particularly useful for stabilizing the position of the filter element(s), since gravity tends to release them from their operating position.

[0023] The filter element or a second filter element can be supported on the housing cover when the housing pot is closed with the housing cover. In this way, the filter element or the filter elements can be moved into their respective operating position for operation of the air filter and fixed in this position. The housing cover and the filter element can interact in particular via a conical structure. An end plate of the filter element can have a recess for engagement of an extension of the housing cover. In this way, the transfer of the filter element or the filter elements from a position in contact with the support structure on the guide device into the operating position can be facilitated.

[0024] Also within the scope of the present invention is a filter housing for an air filter according to the invention described above. The filter housing enables the aforementioned advantages of the air filter according to the invention to be utilized. The filter housing has a housing pot and a housing cover. A guide device is formed in the housing pot, which, when the filter element is inserted into the housing pot, extends into the filter element and can be brought into contact with the support structure arranged on the inside of a filter medium. For further features and advantages of the filter housing, reference is made to the preceding description. Short description of the drawings

[0025] Further features and advantages of the invention will become apparent from the following detailed description of exemplary embodiments of the invention, from the patent claims, and from the figures of the drawing, which illustrate details of the invention. The features mentioned above and those further described may be implemented individually or in combination in any suitable variants of the invention. The features shown in the drawing are presented in such a way that the special features of the invention can be clearly seen. In the drawing: Fig. 1 shows a first embodiment of an air filter according to the invention with a filter housing according to the invention, which has a guide device with a holding element that engages in a support structure of a filter element arranged in the filter housing, in a schematic sectional view; Fig. 2 an enlarged section of Fig. 1, wherein it can be seen that the holding element engages behind a web of the support structure; Fig. 3 the air filter from Fig. 1 with the housing cover removed, the filter element being tilted in the housing pot so that the support structure rests against the guide device, in a schematic sectional view; Fig. 4 the housing pot of the air filter from Fig. 1 in a schematic perspective view; Fig. 5a, Fig. 5b a second embodiment of an air filter according to the invention in a partial, schematic sectional view similar to that in Fig. 2, where the filter element is in Fig. 5a is in an operating position and in Fig. 5b rests against a guide device; Fig. 6 shows a third embodiment of an air filter according to the invention with a first and a second filter element, in a schematic sectional view; Fig. 7 the filter housing and the first filter element of the air filter from Fig. 6, wherein the first filter element rests against the guide device, in a schematic sectional view. Embodiments of the invention

[0026] Fig. Figure 1 shows an air filter 10 in a first embodiment. The air filter 10 has a filter housing 12 formed with a housing pot 14 and a housing cover 16. The air filter 12 further has a filter element 18. The filter element 18 is accommodated in the filter housing 12 and separates a dirty side 20 from a clean side 22.

[0027] The filter element 18 has a filter medium 24. The filter medium 24 is formed here by a zigzag-folded paper. The filter medium 24 surrounds a longitudinal axis 26 of the filter element 18 in a ring shape. The longitudinal axis 26 is aligned approximately horizontally when the air filter is in use, in particular with a maximum deviation of 25° from the horizontal. In a cross-section perpendicular to the longitudinal axis, the filter element 18 or the filter medium 24 can be oval, in particular flat-oval. Along the longitudinal axis 26, the filter medium 24 can be conical.

[0028] The filter element 18 allows flow from the radial outside to the radial inside. The filter medium 24 is supported radially on the inside by a support structure 28. The support structure 28 is designed here in the form of a support tube with circumferentially extending webs 30 and axially extending webs 32. The filter medium 24 is enclosed by an end plate 34, 36 on each of its two end faces.

[0029] In Fig. 1, the filter element 18 is in an operating position. The end plate 34 lies sealingly against a sealing contour 37 of the housing bowl 14. The dirty side 20 and the clean side 22 are thus fluidically separated from each other. The end plate 36 supports the filter element 18 against the housing cover 16, which closes the housing bowl 14.

[0030] The housing pot 14 has a guide device 38, see also Fig. 2 and Fig. 4. In the embodiment shown, the guide device 38 is formed with two guide ribs 40 running parallel to each other, see Fig. 4. Viewed in the direction of the parallel offset, the guide ribs 40 are congruent to each other. The guide ribs 40 can be connected to each other by a transverse rib 42, see Fig. 4. The guide ribs 40 extend here between opposite wall sections 43a, 43b in the clean-side outlet area of ​​the housing pot 14.

[0031] When the filter element 18 is inserted into the housing pot 14, in particular when it has been pushed forward to the sealing contour 37, the guide device 38 protrudes into the filter element 18. The guide device 38 can thus guide the filter element 18 to the sealing contour 37 during insertion. When the filter element 18 is removed from the housing pot 14, the guide device 38 can limit movements of the filter element 18 transversely to the longitudinal axis 26.

[0032] In the embodiment shown here, the guide device 38 has a holding element 44. The holding element 44 is designed as a projection which projects upwards on the guide device 38 in the (horizontal) position of use of the air filter 10 or filter housing 12. As shown in particular in Fig. 2, the holding element 44 engages behind one of the webs 30 of the support structure 28. To remove the filter element 18 from the housing pot 14, the filter element 18 must therefore be tilted or lifted against the effect of gravity.

[0033] In Fig. 3 shows the air filter 10 with the housing cover 16 removed. Since the filter element 18 can no longer be supported on the housing cover 16, it tilts downward due to gravity (compare the direction of action of the gravitational acceleration g). The longitudinal axis 26 of the filter element 18 no longer coincides with a horizontal axis 46 of the housing pot 14. In the position of use, the horizontal axis 46 runs approximately perpendicular to the gravitational acceleration g; in particular, the horizontal axis 46 and the direction of action of the gravitational acceleration g can intersect at an angle between 60° and 120°. The sinking or tilting of the filter element 18 is limited by the guide device 38 in that the support structure 28 of the filter element 18 comes into contact with the guide device 38. The guide ribs 40 can have contact flanks 48 for this purpose.

[0034] When the filter housing 12 is open, the retaining element 44, by engaging the support structure 28, prevents the filter element 18 from detaching from the housing pot 14 on its own, i.e., without further action. In particular, the retaining element 44 can ensure that the end plate 34 remains in the region of the sealing contour 37. However, the sealing of the raw side 20 with respect to the clean side 22 can be eliminated.

[0035] As can be seen particularly in the comparison of Fig. 1 and Fig. 2 with the Fig. 3, the filter element 18 is lifted off the guide device 38 when the filter housing 12 is closed, ie when the housing cover 16 is sealingly attached to the housing pot 14. In other words, in the operational state of the air filter 10 (compare Fig. 1) the support structure 28 does not engage the guide ribs 40. This is achieved by supporting the filter element 18 on the housing cover 16 via the end plate 36.

[0036] Fig. 5a and Fig. 5b show sections of a second embodiment of an air filter 50. The air filter 50 corresponds in structure and function essentially to the previously described air filter 10, compare Fig. 1 to 4. In this respect, reference is made to the above description.

[0037] The guide device 38 of the housing pot 14 of the air filter 50—unlike the air filter 10—does not have a retaining element for engagement with the support structure 28 of the filter element 18. Instead, the guide ribs 40 are provided with smooth contact flanks 48. When the filter housing 12 is open, the support structure 28 rests against the contact flanks 48, see Fig. 5b. This limits the sinking or tipping of the filter element 18. The filter element 18 can be pulled out of the housing pot 14 without lifting it. When the filter housing 12 is closed, the filter element 18 is again lifted off the guide device 38, see Fig. 5a.

[0038] Fig. Figure 6 shows a third embodiment of an air filter 52. The air filter 52 has a first filter element 54 and a second filter element 56. The second filter element 56 is a main filter element; the first filter element 54 is a secondary filter element, which is arranged on the clean side of the main filter element. The second filter element 56 is essentially like the (single) filter element 18 of the air filter 10 described above, see Fig. 1 to 4. A filter housing 12 of the air filter 52 also corresponds in its basic structure to the filter housing 12 of the air filter 10. In this respect, reference is made to the above description.

[0039] The first filter element 54 is V-shaped in longitudinal section. An open end of the first filter element 54 is enclosed by an end plate 58. A filter medium 60 rests on the outside of a support structure 62. The filter medium 60 can be formed from a nonwoven fabric.

[0040] A guide device 38 of a housing pot 14 projects into the first filter element 54. A holding element 44 of the guide device 38 can engage behind a web 64 of the support structure 62.

[0041] In the ready-to-use state, an end plate 36a of the second filter element 56 rests against a housing cover 16. At the other end, an end plate 34a of the second filter element 56 rests against the end plate 58 of the first filter element 54. The end plates 34a and 58 jointly engage in a sealing contour 37 of the housing cup 14 and bear sealingly against the housing cup 14 or against one another. By being supported on the end plate 34a of the second filter element 56, the first filter element 54 is moved into the operating position. In the operating position, the first filter element 54, in particular its support structure 62, is lifted from the guide device 38. A tip 66 of the first filter element 54 lies on a horizontal axis 46 of the filter housing 12 in the operating position.

[0042] Fig. 7 shows the first filter element 54 of the air filter 52 from Fig.6 in the opened housing pot 14, without the second filter element 56 and without the housing cover 16.

[0043] Without support from the second filter element 56, the first filter element 54 sinks due to gravity (gravitational acceleration g) until its support structure 62 rests against the guide device 38. In other words, the first filter element 54 tilts downward. The tip 66 of the first filter element 54 is now located below the horizontal axis 46 of the filter housing 12. The retaining element 44 ensures that the end plate 58 remains in the area of ​​the sealing contour 37. To remove the first filter element 54, the rear grip can be released by lifting the tip 66.

[0044] In summary, the invention relates to air filters with a filter housing and at least one filter element. The filter housing has a guide device that projects into the filter element or one of the filter elements. When installing or removing the filter element in or from the filter housing, the filter element can be aligned or guided by contact with the guide device. The guide device can have a holding element. The holding element can hold the filter element in a position in which an end plate is located in the region of a housing-side sealing contour for this end plate. The end plate of the filter element can be aligned approximately vertically in a use position of the air filter, in particular inclined by a maximum of 30° relative to the vertical. List of reference symbols 10; 50; 52 air filters 12 filter housings 14 Housing pot 16 Housing cover 18 Filter element 20 raw pages 22 Clean side 24; 60 filter medium 26 Longitudinal axis 28; 62 support structure 30, 32; 64 bridges 34, 36; 34a, 36a, 58 end plate 37 Sealing contour 38 Guide device 40 guide rib 42 transverse rib 43a, 43b wall sections 44 Holding element 46 Horizontal axis 48 Investment flank 54 first filter element 56 second filter element 66 top g acceleration due to gravity

Claims

[1] Air filter (10; 50; 52) comprising - a filter housing (12) with a housing pot (14) and a housing cover (16), and - a filter element (18; 54) designed as a hollow body with a filter medium (24; 60) and a support structure (28; 62 arranged on the inside of the filter medium (24; 60), which can be arranged in the filter housing (12), wherein the housing pot (14) has a guide device (38) which, when the filter element (18; 54) is inserted into the housing pot (14), extends into the filter element (18; 54) and can be brought into contact with the support structure (28; 62). [2] Air filter (10; 50; 52) according to claim 1, characterized by that the support structure (28; 62) is lifted off the guide device (38) when the housing pot (14) is closed with the housing cover (16). [3] Air filter (10; 52) according to claim 1 or 2, characterized bythat the guide device (38) has a holding element (44) for engaging in the support structure (28; 62) of the filter element (18; 54), in particular for engaging behind a web (30; 64) of the support structure (28; 62), or that the support structure (28; 62) has a holding element for engaging in the guide device (38). [4] Air filter (10; 50; 52) according to one of the preceding claims, characterized by that the guide device (38) has at least one guide rib (40), preferably wherein the guide rib (40) extends between two opposite wall sections (43a, 43b) of the housing pot (14). [5] Air filter (10; 50; 52) according to claim 4, characterized by that the guide device (38) has two spaced-apart guide ribs (40). [6] Air filter (10; 50; 52) according to claim 5, characterized bythat the two guide ribs (40) are congruent to one another, preferably wherein the guide ribs (40) are arranged offset parallel to one another. [7] Air filter (10; 50; 52) according to claim 5 or 6, characterized by that the guide ribs (40) are connected to one another by a transverse rib (42). [8] Air filter (10; 50; 52) according to one of the preceding claims, characterized by that the filter element (18; 54) has an oval, in particular stadium-shaped cross-section. [9] Air filter (10; 50) according to one of the preceding claims, characterized by that the filter medium (24) is formed with a zigzag-folded filter medium, in particular paper. [10] Air filter (52) according to one of the preceding claims, further comprising a second filter element (56) which can be arranged in the filter housing (12) in addition to the filter element (54). [11] Air filter (52) according to claim 10, characterized bythat the support structure (62) of the filter element (54) is lifted off the guide device (38) when the second filter element (56) is inserted into the housing pot (14) and the housing pot (14) is closed with the housing cover (16). [12] Air filter (10; 50; 52) according to one of the preceding claims, characterized by that the guide device (38) is arranged on the clean side. [13] Air filter (10; 50; 52) according to one of the preceding claims, characterized by that the filter element (18; 54) in the installed state encompasses a horizontally extending axis at least in the region of the guide device (38). [14] Air filter (10; 50; 52) according to one of the preceding claims, characterized by that the filter element (18) or a second filter element (56) is supported on the housing cover (16) when the housing pot (14) is closed with the housing cover (16). [15] Filter housing (12) for an air filter (10; 50; 52) according to one of the preceding claims.

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