Filter element for use in a filter and filter with a filter element

Abstract

The invention relates to a filter element (2), in particular a replaceable filter element, in particular for separating particles and / or gases and / or liquids, in particular a filter cartridge, for use in a filter, in particular a compressed air filter, the invention relates to a filter element, in particular as part of a filter having a plurality of filter stages, comprising a substantially tubular main body (27) having an annular end face (21) facing the filter head, an underside (28), and a circumferential surface (29), a plurality, preferably four, of retaining arms (30) extending radially with respect to a central axis (18) being provided in the region of the end face (21), an annular filter element sealing surface (6) is provided on the end face (21), wherein the retaining arm (30) protrudes relative to the filter element sealing surface (6). The invention also relates to a filter having such a filter element (2).

Description

[0001] The present application is a divisional application of the parent application of Chinese Patent Application No. 202080067071.7, filed on September 9, 2020, entitled “Filter Element for Use in a Filter and Filter Having a Filter Element” (PCT International Application No. PCT / EP2020 / 075203 entering China National Phase), the disclosure of which is incorporated herein by reference in its entirety. TECHNICAL FIELD

[0002] The present application relates to a filter element, in particular a replaceable filter element, in particular for separating particles and / or gases and / or liquids, in particular a filter cartridge, the filter element being used in a filter, in particular a compressed air filter, the filter element being part of a filter having a plurality of filter stages. The filter element comprises a substantially tubular main body having an annular end side facing towards a filter head, a lower side facing away from the filter head spaced apart from the end side, a peripheral surface extending along a central axis, in particular a rotational axis, wherein the peripheral surface connects the end side and the lower side to one another. In the region of the end side, a plurality of, preferably four, retaining arms extending radially with respect to the central axis are provided, wherein a circular annular filter element sealing surface is also provided at the end side.

[0003] The present application also relates to a filter having such a filter element. BACKGROUND

[0004] Filter elements are generally used for filtering a flowable medium within a filter. Such a medium can be, for example, a gas, but also a liquid, for example water or fuel, etc. The filter element is traversed by the medium to be filtered, wherein impurities are separated out. Such a filter element generally has a main body in which the filtering medium is present which is traversed. A filter head is generally provided via which the fluid to be filtered is fed and the filtered fluid is discharged. Furthermore, similar filter elements have a securing device by means of which the filter element can be secured relative to the filter head in order to be sealed relative to the filter head via a sealing body. To this end, the filter element can be, for example, screwed directly to the filter head. Another type of securing takes place via a filter sleeve or filter head, wherein the filter element is inserted into the filter sleeve and abuts against the closed end of the filter sleeve. Here, the closed end of the filter cartridge forms a seat for the filter head, wherein the filter element is clamped between the filter head and the seat.

[0005] The filter element mentioned at the outset is known from US 2007 / 0095744 Al. There, it is a fluid filter having a replaceable filter cartridge, which has a tubular main body, a closed end and an annular open end side. Furthermore, a retaining arm is provided, which lies in a recess in the open side of the filter sleeve, wherein the retaining arm is retracted relative to a filter element sealing face, at which the filter element seals towards the filter head. SUMMARY

[0006] The object on which the invention is based is to provide a filter element having a structurally improved retaining element.

[0007] The object is achieved by a filter element according to claim 1.

[0008] Advantageous design variants are the subject matter of the dependent claims.

[0009] The filter element according to the invention can be designed as a replaceable filter element for use in a filter, in particular for separating particles and / or gases and / or liquids, in particular in the form of a filter cartridge.

[0010] The filter element comprises a substantially tubular main body, which has an annular end side towards the filter head. Furthermore, a lower side spaced apart from the end side facing away from the filter head is provided.

[0011] The filter element furthermore has a circumferential surface, which extends along a central axis, in particular a rotational axis, and connects the end side and the lower side to one another. In the region of the end side, a plurality of, preferably four, retaining arms extending radially relative to the central axis are provided. A (circular) annular filter element sealing face is provided at the end side, wherein the retaining arms protrude relative to the filter element sealing face. The retaining arms serve for positioning the filter element and as a retaining element of the filter cartridge, in turn explicitly determining the position of the filter cartridge relative to the filter head. Thereby, a flow through the filter element is achieved as structurally determined as described above.

[0012] Due to the retaining arms protruding relative to the filter element sealing face, an advantageous force introduction is achieved. Furthermore, the protruding retaining arms protect the filter element sealing face from damage when transporting the filter element or when operating / installing the filter element. Furthermore, a material build-up in production can be prevented.

[0013] If an explicit rotational position is desired, at least one of the retaining arms can be designed differently from the other retaining arms, which then engage into a corresponding receiving device at the filter cartridge.

[0014] The cross section of the retaining arm can be essentially L-shaped. The retaining arm can also project radially outward relative to the filter element sealing surface. It is also advantageous if the retaining arm projects radially outward at the ring surface. A particularly advantageous securing of the filter element to the filter head can be provided by a retaining arm designed in this way.

[0015] The retaining arm is preferably fixedly connected to the filter element sealing surface, preferably configured in one piece with the filter element sealing surface. This enables the positioning of the retaining arm relative to the filter element sealing surface, and thus ultimately the optimal positioning of the filter element relative to the remaining filter.

[0016] It is particularly advantageous if the retaining arm has a support surface, respectively, which points in the opposite direction to the filter element sealing surface, wherein the support surface is preferably convexly arched. The convex arching of the support surface extends in the axial direction, wherein the support surface is connected to the free end of the retaining arm and has a length of at least 3 mm and at most 10 mm in the radial direction. A particularly advantageous force transmission between the retaining arm and the filter element sealing surface is thus achieved. The accommodation of the retaining arm in the corresponding recess is also simplified.

[0017] Additionally, a centering bevel can be provided at the transition between the retaining arm and the ring surface. Here, the centering bevel extends from the ring surface in the direction of the retaining arm at an angle of between 5° and 70°, preferably between 20° and 40°, relative to the center axis. Here, the centering bevel connects the ring surface and the support surface to one another. By means of the centering bevel, the positioning of the filter element relative to the filter head and in the filter sleeve is improved or aligned in the filter sleeve and kept at a certain distance therefrom.

[0018] The retaining arm can also have an end surface at the exposed end of the retaining arm, which points away from the ring surface in the radial direction. Preferably, the spacing between the center of the filter element sealing surface and the end surface in the radial direction is between 12 and 18 mm, wherein the spacing from the center of the filter element sealing surface can also be between 14 and 16 mm. The minimum spacing between the filter element sealing surface and the support surface is between 0 and 4 mm, preferably between 1 and 2 mm, in the axial direction. The maximum spacing between the filter element sealing surface and the support surface is between 4 and 6 mm. By this dimensional design of the retaining arm, an especially stable fit of the retaining arm in the corresponding recess is ensured. In addition, the end surface serves as an engagement area for removing the filter element from the surrounding filter sleeve, thus simplifying the replacement of the filter element.

[0019] Furthermore, the filter element can be designed such that substantially only an axial force acts on the filter element sealing surface, wherein preferably the holding arm forms a bearing against the axial force. Here, the axial force is formed by the pressing of the sealing body against the filter element sealing surface. The holding arm can be flexible in the axial direction and acts as a compensation element between the sealing body and the receiving means for the holding arm.

[0020] Furthermore, the sealing body lies against the (circular) ring-shaped filter element sealing surface of the filter element, such that the sealing body separates the outer space, which lies outside the filter element, from the inner space, which lies inside the filter, from one another between the filter head and the filter element. Thereby, the clean gas space is separated from the raw gas and a particularly advantageous connection is created between the filter element and the filter head.

[0021] As a further design feature, the substantially tube-shaped filter sleeve can be provided with an open filter sleeve end side facing the filter head and a filter sleeve outer side running along the lateral surface, wherein preferably the filter sleeve surrounds the filter element and is separated from the environment. Furthermore, the filter sleeve end side can have receiving means for the holding arm, wherein the filter element is in contact with the filter sleeve only via the holding arm arranged in the receiving means and the filter element is configured to hang in the filter sleeve with other parts hanging freely. This connection between the filter head, the filter cartridge and the filter sleeve can be realized with particularly few additional components and via simple geometries and is therefore particularly inexpensive.

[0022] The receiving means can be formed at least by a continuous cut-out, which begins at the filter sleeve end side and runs radially with respect to the central axis, the receiving means preferably receiving the holding arm. Furthermore, the end of the cut-out can form a bearing, which is concavely shaped in a manner matching the convex support surface of the holding arm. Here, the bearing absorbs the forces formed by the pressing of the sealing body and the pressure load. A particularly simple positioning of the filter element is achieved by the cooperation between the receiving means and the holding arm, wherein a simultaneous compensation of the sealing body as well as of dimensional deviations is achieved.

[0023] The sealing body can be an axial sealing. Furthermore, the filter sleeve can be sealed towards the filter head by means of a radial seal. In order to form a closed space around the filter element, the filter sleeve can be configured in the form of a pot and correspondingly closed at the end facing away from the filter head. On the one hand, a sealing of this form enables a simple installation of the filter cartridge, on the other hand, it can be realized in a particularly space-saving manner.

[0024] At least two of the receiving means can be configured as receiving locking means for receiving the holding arm and a holding peg. The holding peg is preferably attached at the filter head and can point radially to the central axis.

[0025] The receiving locking device is advantageously designed such that the retaining peg engages in a bayonet connection with the receiving locking device. By this design a particularly simple exchange of the filter element is achieved, wherein at the same time a sufficient axial movement is achieved for clamping the seal body.

[0026] For the realization of the bayonet connection, the receiving locking device has, in addition to the axial cutout of the receiving device, a fixing expansion, which is preferably formed by a further cutout, which extends away from the axial cutout and which essentially extends in the circumferential direction around a portion of the filter sleeve. Additionally, the fixing expansion can have a locking undercut, which is formed by a recess on the filter head side in the end region of the fixing expansion. A bayonet connection designed in this way can be produced particularly inexpensively and achieves a particularly secure fixing of the filter sleeve at the filter head, which is ensured by the locking undercut itself in the case of a pressure loading of the filter.

[0027] A further embodiment relates to a filter having at least two filter stages. The filter elements have, for example, different filter properties. The sealing devices for the sealing between the filter elements and the filter head are preferably essentially of the same type. Additionally or alternatively, the receiving devices of the filter sleeve and the retaining arms of the filter elements of the different filter stages can essentially be of the same type.

[0028] In such a filter system, the seals between the filter elements and the filter head, the filter element-side sealing surface and the filter head-side sealing surface, the receiving devices of the filter sleeve or the retaining arms of the filter elements of the different filter stages can be configured identically.

[0029] Such a filter element or sealing device between the filter element and the filter head is designed such that the filter element or the sealing device can be loaded with greater pressure from the outside than from the inside. Preferably, at least one of the filter elements or one of the sealing devices of the entire filter is loaded in the opposite direction. Thereby, a uniform construction of the different filter stages can be provided. Furthermore, with this construction, the filter elements can be loaded or flowed through from the outside to the inside and from the inside to the outside. Preferably, one of the filter elements is flowed through in the radial direction from the inside to the outside and the other filter element is flowed through from the outside to the inside, i.e. towards the central axis.

[0030] Such a sealing device can be used, for example, as a seal between a filter element and a filter head of a filter having multiple filter stages, especially in the field of compressed air filters. Such a filter element is preferably a filter cartridge.

[0031] The sealing device includes an annular, resilient sealing body, a filter head, and a filter element sealing surface. The sealing body has: a filter head side facing the filter head sealing surface, an opposing filter element side facing the filter element sealing surface, an inner surface surrounding the inner side, and an opposing outer surface surrounding the side surface. The filter head side includes a first surrounding recess between the inner and outer surfaces, while the filter element side has a second surrounding recess between the inner and outer surfaces. The filter head side abuts against the filter head sealing surface at least partially surrounding it, while the filter element side abuts against the filter element sealing surface at least partially surrounding it. The filter head sealing surface and the filter element sealing surface are formed at least by an inner surrounding surface and an outer surrounding surface.

[0032] Here, the facets of the filter head sealing surface and the filter element sealing surface rise towards the center between the facets, such that, substantially in the direction of the central axis of the seal body, the spacing between the inner facets decreases from the inside to the outside, and the spacing between the outer facets decreases from the outside to the inside. The facets mate with the recesses, such that the seal body wedges between the inner and / or outer facets under pressure loading from the inner and / or outer surfaces in the direction of the applied force.

[0033] A constriction is formed between the filter head sealing surface and the filter element sealing surface by a rising facet, extending outwards from the middle between the two facets on both sides. The constriction mates with a corresponding tapered portion of the seal body. If pressure is applied to the seal body from the inside or outside, the seal body is pressed against the inclined sidewall of the constriction, which is on the side where the force is applied. Here, the seal body is non-flexible, so that under normal use, pressure loading does not cause it to be strongly compressed, thus preventing the seal body from being squeezed through the constriction in the direction of the force.

[0034] By pressing the seal body into the contraction section, a wedging or higher compression of the seal body between the opposing sealing surfaces is achieved, which in turn increases the sealing effect. This is derived from the pressure loading obtained on both the outer and inner circumferential surfaces.

[0035] The sealing effect is automatically strengthened when the load originates from the inside or outside.

[0036] Specifically, when a pressure difference exists between the inner and outer surfaces, the sealing fit between the facets and the recesses is strengthened through the interaction of the force and the wedging action. If a greater pressure is applied to the seal body through the pressure difference at the inner or outer surface than that applied to the opposing surfaces, the seal body is compressed in the direction of the force, and the space between the facets decreases in that direction. The wedging action is generated from the interaction of the force with the contraction between the filter head sealing surface and the filter element sealing surface. Through the wedging action, the seal is more strongly pressed against the facets, thereby strengthening the sealing effect as the pressure difference increases.

[0037] Furthermore, the sloping design makes it easier to position the seal or filter element relative to the filter head.

[0038] Particularly advantageously, the seal body has a surrounding retaining groove on the filter head side for receiving a retaining element. Specifically, the retaining element is designed to form a detachable locking connection in a manner that engages with the retaining groove, wherein the locking connection holds the filter head side of the seal body against the filter head sealing surface. Here, the retaining groove extends in the area of ​​the recess, preferably extending in the bottom of the first recess. The retaining element protrudes between the two facets of the filter head sealing surface. Preferably, the retaining element protrudes along an annulus relative to the filter head sealing surface. This locking connection reliably retains the seal body at the filter head, which particularly simplifies seal body replacement, for example, in the event of damage.

[0039] It is also particularly advantageous that the second recess extends at least half the width of the filter element side between the inner and outer surfaces, preferably more than two-thirds of it. Additionally, the first recess extends at least half the width of the filter head side between the inner and outer surfaces. This design ensures a particularly good sealing fit because it forms two almost linear sealing surfaces, thus preventing pressure on the vulnerable surfaces.

[0040] Therefore, it is particularly advantageous that the sealing body does not abut against the filter element sealing surface in the surrounding region of the second recess, preferably in the region of the lowest point of the second recess. It is also particularly advantageous that the sealing body does not abut against the filter element sealing surface, at least partially, in the region closest to the filter head sealing surface. Thus, a first external sealing surface and a second internal sealing surface with similar sealing characteristics can be created, thereby ensuring similar lateral load-bearing capacity of the seal.

[0041] The retaining element and retaining groove can be designed such that a sealing fit exists between the bottom of the retaining groove and the area of ​​the retaining element closest to the sealing surface of the filter element. This is preferably achieved in such a way that the axial depth of the retaining groove is less than the axial height of the retaining element when the seal is not installed. This achieves the creation of an annular seal with a small area, which provides a fluid seal even under weak compression from the seal body.

[0042] The locking connection can be formed by a single-sided extension at the retaining element and a corresponding recess in the seal body, wherein the extension protrudes radially outward relative to the central axis of the seal body. Here, the opposite side of the retaining element has no protrusion and is flat in the direction of the central axis. Therefore, the cross-section of the retaining element is essentially L-shaped. This design of the retaining element ensures maximum service life of the seal body because the retaining groove is only applied to the outer side.

[0043] Particularly advantageous is that the sealing body has a hardness between 60 Shore A and 90 Shore A, preferably between 60 Shore A and 80 Shore A, and especially preferably 70 Shore A. This ensures that the sealing body has sufficient elasticity for sealing between the sealing surfaces, while also having sufficient rigidity to ensure wedging action to the desired degree.

[0044] Also advantageous is that the facets of the filter head sealing surface and / or the filter element sealing surface have an interior angle α relative to each other in the radial direction with respect to the central axis of less than 180°, preferably between 130° and 170°. A particularly advantageous range is between 145° and 155°. This angle ensures a particularly advantageous distribution of forces and the formation of a wedging effect.

[0045] Also particularly advantageous is that the filter head side of the sealing body has two annular surrounding sealing surfaces, with retaining grooves extending into the sealing body between the sealing surfaces, and the two sealing surfaces forming an exterior angle α1 of less than 180°, preferably between 125° and 175°, relative to the central axis in the radial direction. Here, a particularly advantageous range is between 140° and 150°. Therefore, optimal interaction between the sealing surfaces on the filter head side and the sealing surfaces on the filter head side of the sealing body is ensured, thereby ensuring a high sealing effect and the formation of a wedging effect.

[0046] Also advantageous is that, in the uninstalled state, the second recess has a greater depth in the axial direction than the height offset of the facet. Here, the height offset of the facet can be understood as a distance that the facet extends axially opposite to the filter head. Preferably, the height of the facet is less than 70% of the depth of the second recess. The greater depth of the second recess provides a gap between the filter head sealing surface and the filter element sealing surface, which compensates for any inaccuracies in the mutual positioning of the two surfaces.

[0047] In another particularly preferred embodiment, the sealing device is designed for use in filters in which the filter elements follow the filter head along a mounting axis that extends parallel to or is the same as the central axis of the seal. This allows for particularly simple installation and removal of the filter elements.

[0048] The filter head of the corresponding filter preferably has a hollow cylindrical filter sleeve end-side recess that extends from the side portion of the end side and extends substantially axially symmetrically with respect to the central axis of the filter element into the filter head, and accommodates the end side of the filter sleeve. Here, the filter sleeve end-side recess is located outside the sealing surface of the filter head in the radial direction relative to the central axis. This achieves a particularly compact construction.

[0049] Furthermore, the corresponding filter head may have two retaining plug holes extending radially relative to the central axis, preferably opposite each other, wherein the retaining plug holes accommodate a retaining plug, which is part of a bayonet connection. Preferably, a metal-to-metal tapered seal for sealing towards the environment is provided between the retaining plug and the filter head. This design enables particularly simple and inexpensive manufacturing.

[0050] Another particularly advantageous aspect is that the sealing device is constructed such that the inner and outer surfaces of the seal body do not abut against either the filter head side or the filter element side. Correspondingly, the seal body seals essentially only against the filter head sealing surface and the filter element sealing surface via axial force. This axially sealed seal also enables exceptionally simple installation and removal of the filter element, as a significantly smaller path is required in the axial direction to achieve sufficient sealing.

[0051] Provided this is relevant to the corresponding explanation, the above embodiments generally begin with the installed state of the filter element having a compressed seal. In this state, the seal seals between the internal and external spaces. This will be explicitly mentioned in embodiments involving a disassembled state with an uncompressed seal.

[0052] The filter according to the invention may have only the main features and any combination of other described features. Furthermore, even in different embodiments, the various features of the embodiments may be arbitrarily combined with each other. In addition, the invention also relates to filters having the described filter elements, filters having the described sealing devices, and any combination of the sealing device and the filter element itself, or the filter element and the sealing device. Attached Figure Description

[0053] The invention will now be explained with reference to the accompanying drawings. The drawings show: Figure 1 A partial cross-sectional view of a filter stage with sealing devices and filter elements is shown. Figure 2 A partial view of the cross-section of the sealing device is shown. Figure 3 A magnified partial view of the cross-section of the sealing device is shown. Figure 4This diagram shows the force action of the seal body under load on the axial and circumferential sides. Figure 5 A perspective view of the filter element is shown. Figure 6 A perspective view of a filter sleeve with filter elements is shown. Figure 7 A partial cross-sectional view of the filter head from below is shown, and Figure 8 A side view of a multi-stage filter is shown. Detailed Implementation

[0054] Figure 1 and Figure 2 A sealing device 1 for a filter, particularly a compressed air filter, is shown. The sealing device, especially as part of a filter having multiple filter stages 45, is used to provide a fluid seal between the filter element 2, particularly the filter cartridge, and the filter head 3. Also shown are an annular, resilient sealing body 4, and sealing surfaces 5 and 6 of the filter head and filter element.

[0055] The sealing body 4 has a filter head side 7 facing the filter head sealing surface 5, an opposing filter element side 8 facing the filter element sealing surface 6, an inner surface 9 surrounding the inner side, and an opposing outer surface 10 surrounding the side surface. The filter head side 7 has a first surrounding recess 11 between the inner surface 9 and the outer surface 10, and the filter element side 8 also has a second surrounding recess 12 between the inner surface 9 and the outer surface 10.

[0056] The filter head sealing surface 5 and the filter element sealing surface 6 are formed by at least an inner circumferential surface 13 and an outer circumferential surface 14. As can be seen in the figures, the filter head side 7 at least partially circumferentially abuts against the filter head sealing surface 5, and the filter element side 8 at least partially circumferentially abuts against the filter element sealing surface 6. Here, the surfaces 13, 14 of the filter head sealing surface 5 and the surfaces 13, 14 of the filter element sealing surface 6 rise towards the center between the surfaces 13, 14, such that in the axial direction toward the central axis 18, the spacing between the inner surfaces 13 decreases from the inside out, and the spacing between the outer surfaces 14 decreases from the outside in. Similarly, the inner surface 9 and the outer surface 10 of the sealing body 4 neither abut against the filter head side nor the filter element side, and correspondingly seal only axially relative to the central axis 18.

[0057] Furthermore, a radial seal 46 is shown, which seals the filter between the filter head 3 and the filter sleeve 33 relative to the environment or ambient atmosphere. Seal 46 is a seal that is essentially applied radially to the central axis 18.

[0058] Also from Figure 1 andFigure 2 It is evident that the mating surfaces 13 and 14, and the recesses 11 and 12, cooperate such that, under pressure loading from the inner surface 9 and / or the outer surface 10 along the directions of forces F1 and F2, the sealing body 4 wedges between the inner surface 13 and / or the outer surface 14. This wedging action strengthens the sealing fit between the mating surfaces 13 and 14 and the recesses 11 and 12, where forces F1 and F2 are generated only when there is a pressure difference between the inner surface 9 and the outer surface 10. Figure 4 The following force is shown, which acts on sealing surfaces 5 and 6 when sealing device 1 is loaded on the outside F1.

[0059] from Figure 1 It is also concluded that the sealing device 1 is designed for use in a filter, wherein the filter element 2 is installed at the filter head 3 along an installation axis that extends in the same direction as the central axis 18 of the sealing body 4.

[0060] The sealing body 4 abuts against the annular filter element sealing surface 6 of the filter element 2, and the external space 31 outside the filter element 2 and the internal space 32 inside the filter element 2 are separated from each other between the filter head 3 and the filter element 2.

[0061] Figure 3 The diagram shows that the sealing body 4 has a surrounding retaining groove 15 on the filter head side 7 for receiving a retaining element 16. The retaining element 16 is designed to form a removable locking connection 17 in a manner that engages with the retaining groove 15. The locking connection 17 holds the filter head side 7 against the filter head sealing surface 5, wherein the retaining groove 15 extends in the region of the recesses 11, 12, preferably in the bottom of the first recess 11. The retaining element 16 protrudes between the two facets 13, 14 of the filter head sealing surface 5. In particular, the retaining element 16 protrudes along an annulus relative to the filter head sealing surface 5.

[0062] The second recess 12 extends at least half the width of the filter element side 8 between the inner surface 9 and the outer surface 10, preferably extending more than two-thirds of it. The first recess 11 extends at least half the width of the filter head side 7 between the inner surface 9 and the outer surface 10, preferably extending more than two-thirds of it.

[0063] In a portion surrounding the second recess 12, the seal 4 does not abut against the filter element sealing surface 6; this portion is preferably located in the area at the deepest point of the second recess 12. As is visible, the seal 4 does not abut against the filter head sealing surface 5 in the area closest to it.

[0064] Also from Figure 3 and Figure 4 Conclusion: The retaining element 16 and the retaining groove 15 are designed such that, in Figure 4A sealing fit exists between the bottom of the retaining groove 15 shown and the area of ​​the retaining element closest to the filter element sealing surface 6. This is achieved in such a way that, in the state where the seal body 4 is not installed, the depth of the retaining groove 15 of the seal is at least as large as, and preferably less than, the height of the retaining element 16 in the direction of the central axis 18.

[0065] It is also shown that the locking connection 17 is formed by a one-sided extension 19 at the retaining element 16 and a corresponding recess 20 in the sealing body 4. The extension 19 is located relative to the sealing body 4. Figure 1 The central axis 18 shown protrudes outward in the radial direction. The opposite side of the retaining element 16 has no protrusion and is planar in the direction of the central axis 18. The retaining element 16 is designed substantially L-shaped, which... Figure 3 It is shown in a mirror image.

[0066] The seal 4 shown also has a hardness between 60 Shore A and 80 Shore A, preferably 70 Shore A.

[0067] Figure 4 As shown, the facets 13 and 14 of the filter head sealing surface 5 and the filter element sealing surface 6 form an interior angle α less than 180°, preferably between 130° and 170°, relative to each other in the radial direction relative to the central axis 18. Furthermore, the filter head side 5 of the sealing body 4 has two annular surrounding sealing facets 23 and 24, with a retaining groove 15 extending into the sealing body 4 between the sealing facets. The two sealing facets 23 and 24 have an exterior angle α1 less than 180°, preferably between 125° and 175°, relative to each other in the radial direction relative to the central axis 18.

[0068] Because the sealing body 4 is in Figure 4 As shown in the diagram, the second recess 12, in its uninstalled state, has a depth in the direction of the central axis 18 greater than the extension of the facets 13 and 14 toward the center between the two facets 13 and 14 in the direction toward the filter head 3. For example, if the height of the facets 13 and 14 is less than 70% of the depth of the second recess 12, the shown compression of the seal 4 is achieved.

[0069] As can be seen from the inner surface 9 and the outer surface 10 exposed by the distribution: the sealing body 4 is an axially acting seal, which seals essentially only by axial force.

[0070] Figure 5The corresponding filter element 2 is shown here as a filter cartridge. The filter element 2 has a filter element sealing surface 6, which is retracted relative to the end side 21 of the filter element 2. In other words, the end side 21 is formed by a surrounding flange 22 that protrudes relative to the filter element sealing surface 6.

[0071] The filter element 2 shown is a replaceable filter element that can be used to separate particles and / or gases and / or liquids. In particular, it can be a filter cartridge designed for use in filters, especially compressed air filters. Here, the filter can be equipped with multiple filter stages.

[0072] The filter element 2 shown includes a generally tubular body 27 with an annular end side 21, the end side facing towards the side that is still in use. Figure 1 and Figure 7 The filter head 3 is shown in the diagram. Furthermore, the filter element 2 has a lower side 28 spaced apart from the end side 21, the lower side facing away from the filter head 3. Additionally, the filter element 2 has an annular surface 29 extending along the central axis 18, particularly the axis of rotation. As can be seen, the annular surface 29 connects the end side 21 and the lower side 28 to each other. Furthermore, a plurality of, preferably three, particularly preferably four, retaining arms 30 are shown in the region of the end side 21, the retaining arms 30 extending radially relative to the central axis 18. An annular filter element sealing surface 6 is present at the end side 21. The retaining arms 30 protrude relative to the filter element sealing surface 6 and / or relative to the end side 21.

[0073] The retaining arm 30 is substantially L-shaped. Furthermore, the retaining arm 30 protrudes outward in both the axial and radial directions relative to the filter element sealing surface 6 and / or end side 21, wherein the retaining arm 30 protrudes outward in the radial direction from the circumferential surface 29.

[0074] Also from Figure 5 It is concluded that the retaining arm 30 is fixedly connected to the filter element sealing surface 6, and preferably is integrally formed with the filter element sealing surface 6.

[0075] It is also found that the retaining arms 30 each have a support surface 47, which points in the opposite direction to the sealing surface 6 of the filter element. The support surface 47 is convexly arched. The convex arch of the support surface 47 extends radially relative to the central axis 18, wherein the support surface 47 is connected to the free end of the retaining arm 30, preferably to the end face 49, and has a length of at least 2 mm and a maximum of 8 mm in the radial direction. A length between 3 and 6 mm is particularly advantageous. This dimensional design allows for easy removal of the filter element 2 while simultaneously providing sufficient support surface 47 as a support for the receiving device 36.

[0076] The retaining arm 30 has an end face 49 located at its exposed end, which points radially away from the circumferential surface 29 and thus away from the central axis 18. Here, the radial distance between the center of the filter element sealing surface 6 and the end face 49 relative to the central axis 18 is between 12 and 18 mm. Particularly advantageously, the distance between the end face 49 and the center of the filter element sealing surface 6 is between 14 and 16 mm. The axial distance between the filter element sealing surface 6 and the starting point of the support surface 47 is between 0 and 4 mm, preferably between 1 and 2 mm.

[0077] Filter element 2 is designed so that essentially only axial force acts on the filter element sealing surface 6. Retaining arm 30 forms a support 50 to overcome axial force, the support being... Figure 1 The seal 4 shown is formed by compression and abuts against the sealing surface 6 of the filter element.

[0078] A particular advantage is that the retaining arm 30 is flexible in the axial direction, thereby allowing the sealing body 4, which abuts against the filter element sealing surface 6, to... Figure 6 A compensating element is formed between the receiving devices 36 shown. The receiving device 36 receives the retaining arm 30.

[0079] The filter element 2 has a centering bevel 48 at the transition between the retaining arm 30 and the circumferential surface 29. The centering bevel has an angle between 70° and 5° relative to the central axis 18 and extends from the circumferential surface toward the retaining arm 30. Particularly advantageously, the angle between the circumferential surface 29 and the centering bevel 48 is between 20° and 40°. The centering bevel 48 connects the circumferential surface 29 and the support surface 47 to each other, and serves to center the filter element 2 within the surrounding filter sleeve 33.

[0080] Figure 6 A generally tubular filter sleeve 33 with a filter element 2 is shown, wherein the filter sleeve 33 has an open filter sleeve end side 34 facing the filter head 3 and a filter sleeve outer side 35 extending along the side surface. The filter sleeve 33 surrounds the filter element 2 and isolates the interior of the filter from the environment. The filter sleeve end side 34 has a receiving device 36 for a retaining arm 30, wherein the filter element 2 contacts the filter sleeve 33 only via the retaining arm 30 disposed in the receiving device 36, and the filter element is otherwise suspended in the filter sleeve 23.

[0081] The receiving device 36 is formed by at least a continuous axial cut 38 that begins at the end side 34 of the filter sleeve and extends radially relative to the central axis 18, wherein the receiving device 36 receives the retaining arm 30. The end of the cut 38 forms a support 50 that is concavely formed to match the convex support surface 47 of the retaining arm 30, wherein the support 50 absorbs the compressive force generated by the compression of the seal 4.

[0082] Two of the receiving devices 36 are designed to receive locking devices 51, which are used to receive retaining arms 30 and to receive... Figure 8 The retaining bolt 37 is shown. The retaining bolt 37 is attached to the filter head 3 and points radially relative to the central axis 18. The receiving locking device 51 is designed such that the retaining bolt 37 engages with the receiving locking device 51 in a bayonet-type connection.

[0083] In addition to the axial cutout 38, the receiving locking device 51 has a fixing extension 39, which is formed by another cutout that extends away from the axial cutout 38 and extends substantially circumferentially around a portion of the filter sleeve 33. The fixing extension 39 also has a locking undercut 40, which is formed by a recess on the filter head side in the end region of the fixing extension 39.

[0084] Figure 7 The filter head 3 is shown below, but the filter sleeve 33 and filter element 2 are not shown. The filter head 3 has a filter head sealing surface 5. Figures 1 to 3 The sealing body 4 shown abuts against the filter head sealing surface. As can be seen from the figure, a retaining arm recess 41 is provided, which is retracted relative to the filter head sealing surface 5, wherein the retaining arm 30 extends into the retaining arm recess 41 in the installed state.

[0085] The filter head 3 also has a hollow cylindrical filter sleeve end recess 42, which extends from the filter head sealing surface 5 and extends substantially axially symmetrically into the filter head 3 with respect to the central axis 18, and accommodates the filter sleeve end 34 in the installed state, wherein the filter sleeve end recess 42 is outside the filter head sealing surface 5 in the radial direction with respect to the central axis 18.

[0086] The filter head 3 also has two retaining plug holes 43, which extend radially relative to the central axis 18. The retaining plug holes are preferably opposite each other, wherein the retaining plug holes 43 receive retaining plugs 37, which are preferably connected in a bayonet-type manner. Figure 6 The receiving device 36 in the filter sleeve 33 is fitted, wherein preferably, a metal-to-metal conical seal 44 is provided between the retaining bolt 37 and the filter head 3.

[0087] Figure 8A multi-stage filter 45 with multiple filter stages is shown, wherein the filter stages additionally or optionally include the aforementioned features for the sealing device 1 and / or filter element 2. Here, the multi-stage filter 45 also includes filter elements 2 with different filtration characteristics.

[0088] In this multi-stage filter 45, the sealing device 1 and / or the receiving device 36 of the filter sleeve 33 and / or the retaining arm 30 of the filter element 2 for sealing between the filter element 2 and the filter head 3 can be constructed substantially identically to each other according to the features described above. Furthermore, at least one of the filter elements 2 can be subjected to a greater pressure from the outside than from the inside, wherein at least one of the filter elements 2 is subjected to pressure in the opposite manner.

Claims

1. A filter element (2), particularly a replaceable filter element, particularly for separating particles and / or gases and / or liquids, particularly a filter cartridge, used in filters, particularly compressed air filters, particularly as part of a filter 45 having multiple filter stages, the filter element comprising a substantially tubular body (27) having an annular end side (21) facing a filter head (3), a lower side (28) spaced away from the filter head (3) and spaced from the end side (21), and a circumferential surface (29) extending along a central axis (18), particularly a rotation axis. -in, The circumferential surface (29) connects the end side (21) and the lower side (28) to each other. -In this context, a plurality of, preferably four, retaining arms (30) are provided in the region of the end side (21) extending radially relative to the central axis (18). -In this process, an annular, particularly circular, filter element sealing surface (6) is provided at the end side (21). The characteristic feature is that the retaining arm (30) protrudes relative to the sealing surface (6) of the filter element.

2. The filter element (2) according to claim 1, characterized in that, The retaining arm (30) is substantially L-shaped, and / or the retaining arm (30) protrudes outward in the axial and / or radial direction relative to the sealing surface (6) of the filter element, and / or the retaining arm (30) protrudes outward in the radial direction at the circumferential surface (29).

3. The filter element (2) according to any one of the preceding claims, characterized in that, The retaining arm (30) is fixedly connected to the sealing surface (6) of the filter element, and the retaining arm is preferably integral with the sealing surface (6) of the filter element.

4. The filter element (2) according to any one of the preceding claims, characterized in that, Each retaining arm (30) has a support surface (47) facing away from the filter element sealing surface (6), wherein preferably, the support surface (47) is convex and arched, and / or the axial distance between the filter element sealing surface (6) and the support surface (47) is between 0 mm and 4 mm, preferably between 1 mm and 2 mm.

5. The filter element (2) according to any one of the preceding claims, characterized in that, Each retaining arm (30) has an end face (49) located at the exposed end of the corresponding retaining arm (30), the exposed end pointing radially away from the circumferential surface (29), wherein preferably, the radial distance between the center of the filter element sealing surface (6) and the end face (49) is between 12 mm and 18 mm, wherein preferably, the distance from the center of the filter element sealing surface (6) is between 14 mm and 16 mm.

6. The filter element (2) according to any one of the preceding claims, characterized in that, The filter element (2) is designed such that essentially only axial force acts on the filter element sealing surface (6), wherein preferably, the retaining arm (30) forms a support (50) to overcome the axial force, wherein preferably, the axial force is generated by squeezing the sealing body (4) against the filter element sealing surface (6), wherein preferably, the retaining arm (30) is flexible in the axial direction and is formed as a compensating element between the sealing body (4) against the filter element sealing surface (6) and the receiving device (36) that receives the retaining arm (30).

7. A filter (45) having at least one filter head (3), a filter sleeve (33), and a filter element (2), wherein, A sealing body (4) is also provided, which abuts against the annular filter element sealing surface (6) of the filter element (2) so that the sealing body (4) separates the external space (31) and the internal space (32) between the filter head (3) and the filter element (2), the external space being located outside the filter element (2) and inside the filter sleeve (33), and the internal space being located inside the filter element (2).

8. The filter (45) according to claim 7, characterized in that, The filter sleeve (33) is substantially tubular and has an open filter sleeve end side (34) facing the filter head (3) and a filter sleeve outer side (35) extending along the side surface. Preferably, the filter sleeve (33) surrounds the filter element (2) and defines the filter element relative to the surrounding environment. Preferably, the filter sleeve end side (34) has a receiving device (36) for a retaining arm (30). Preferably, the filter element (2) contacts the filter sleeve (33) only via the retaining arm (30) arranged in the receiving device (36), and the filter element is otherwise suspended in the filter sleeve (33).

9. The filter (45) according to claim 7 or 8, characterized in that, The receiving device (36) is formed by at least a continuous cut (38) that begins at the end side (34) of the filter sleeve and extends radially relative to the central axis (18), wherein preferably, the receiving device (36) receives a retaining arm (30), wherein preferably, the end of the cut (38) forms a support (50) that matches a concave support surface (47) to a convex shape, wherein preferably, the support (50) absorbs the compressive force generated by the compression of the seal (4).

10. The filter (45) according to any one of claims 7 to 9, characterized in that, The sealing body (4) is an axially acting seal, wherein preferably, the filter sleeve (33) is sealed toward the filter head (3) by means of a radial seal (46).

11. The filter (45) according to any one of claims 7 to 10, characterized in that, At least two of the receiving devices (36) are configured to receive locking devices (51) for receiving retaining arms (30) and retaining bolts (37), which are preferably attached to the filter head (3) and / or radially oriented relative to the central axis (18), wherein preferably, the receiving locking devices (51) are configured such that the retaining bolts (37) cooperate with the receiving locking devices (51) in a bayonet-like manner.

12. The filter (45) according to any one of claims 7 to 11, characterized in that, The receiving locking device (51) has a fixing extension (39) in addition to having an axial cut (38), wherein preferably, the fixing extension (39) is formed by an additional cut that extends away from the axial cut (38) and extends substantially circumferentially around a portion of the filter sleeve (33), wherein preferably, the fixing extension (39) has a locking undercut (40) formed by a recess on the filter head side in the end region of the fixing extension (39).

13. The filter (45) according to any one of claims 7 to 12, characterized in that, A sealing device (1) is provided, which is used to provide a fluid seal between the filter head (3) and the filter element (2). -The sealing device (1) includes the sealing body (4) and the filter element sealing surface (6) as well as the filter head sealing surface (5). -The annular elastic seal (4) has a filter head side (7) facing the filter head sealing surface (5), a filter element side (8) facing the filter element sealing surface (6), an inner surface (9) surrounding the inner side, and an outer surface (10) surrounding the side surface. - wherein the filter head sealing surface (5) and the filter element sealing surface (6) are at least composed of an inner circumferential surface (13) and an outer circumferential surface (14), wherein the sealing device (1) is configured such that, when pressure is applied from the inner surface (9) and / or the outer surface (10) in the direction of the force, the sealing body (4) wedges between the inner circumferential surface (13) and / or the outer circumferential surface (14).

14. The filter (45) according to any one of claims 7 to 13, characterized in that, The filter stage is provided with at least two filter stages, each having a filter head (3), a filter sleeve (33) and a filter element (2), wherein preferably, the sealing device (1) for sealing between the filter element (2) and the filter head (3), the receiving device (36) of the filter sleeve (33) and the retaining arm (30) of the filter element (2) of the at least two filters are substantially of the same type.

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