EP4034280A1

EP4034280A1 - Filter element for use in a filter, and filter comprising a filter element

Info

Publication number: EP4034280A1
Application number: EP20771521.0A
Authority: EP
Inventors: Norbert Maier; Martin Horstman; Sven Schulze
Original assignee: SATA GmbH and Co KG
Current assignee: SATA GmbH and Co KG
Priority date: 2019-09-25
Filing date: 2020-09-09
Publication date: 2022-08-03
Also published as: DE202019105323U1; WO2021058282A1; CA3155446A1; CN114514058A; US20220370944A1

Abstract

The invention relates to a filter element (2), in particular a replaceable filter element, more particularly for separating particles and/or gases and/or liquids, in particular a filter cartridge for use in a filter, more particularly a compressed air filter, in particular as a component of a filter comprising multiple filtration stages, the filter element comprising a substantially tubular body (27) with an annular end face (21) that faces a filter head, an underside (28), and a circumferential surface (29), wherein multiple, preferably four, retaining arms (30), running radially in relation to the central axis (18), are provided in the region of the end face (21) and a toroidal filter-element sealing surface (6) is provided on said end face (21), and the retaining arms (30) protrude in relation to the filter-element sealing surface (6). The invention further relates to a filter comprising a filter element (2) of this type.

Description

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

The invention 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, for use in a filter, in particular a compressed air filter, in particular as part of a filter with several filter stages. The filter element comprises a substantially tubular body, with an annular end face that faces a filter head, an underside spaced from the end face and facing away from the filter head, a circumferential surface that extends along a central axis, in particular an axis of rotation, wherein the Peripheral surface connects the end face and the underside with one another. In the area of the end face several, preferably four, holding arms extending radially to the central axis are provided, with an annular filter element sealing surface also being provided on the end face.

The invention also relates to a filter with such a filter element.

Filter elements are usually used for the filtration of flowable media within a filter. Such media can for example be gases but also liquids such as water or fuel or the like. The medium to be filtered flows through the filter elements, with impurities being separated out. Such a filter element generally has a body in which there is a filter medium that is flowed through. As a rule, a filter head is provided through which the fluid to be filtered is fed in and the filtered fluid is discharged. Comparable filter elements also have fastening devices with which the filter elements can be fastened relative to the filter head in order to seal the filter head by means of a sealing body. For this purpose, the filter element can be screwed directly to the filter head, for example. Another type of attachment is via a filter sleeve or a filter bowl, the filter element being inserted into the filter sleeve and resting on the closed end of the filter sleeve. Here, the closed end of the filter cartridge forms an abutment for the filter head, the filter element being braced between the filter head and the abutment. A filter element mentioned at the beginning is known from US 2007/0095744 A1. This is a fluid filter with an exchangeable filter cartridge with a tubular body, a closed end and an annular open end face. Furthermore, retaining arms are provided which lie in recesses in the open side of the filter sleeve, the retaining arms projecting back from the filter element sealing surface on which the filter element seals towards the filter head.

The invention is based on the object of providing a filter element with structurally improved holders.

This object is achieved by the filter element according to claim 1.

Advantageous configurations are the subject of the dependent claims.

A filter element according to the invention can be designed as an exchangeable filter element, in particular for separating particles and / or gases and / or liquids, in particular in the form of a filter cartridge, for use in a filter.

The filter element comprises an essentially tubular body with an annular end face which faces a filter head. An underside which is spaced apart from the end face and faces away from the filter head is also provided.

The filter element also has a circumferential surface which extends along a central axis, in particular an axis of rotation, and connects the end face and the underside to one another. In the area of the end face, several, preferably four, holding arms extending radially to the central axis are provided. The (circular) ring-shaped filter element sealing surface is provided on the end face, with the holding arms protruding from the filter element sealing surface. The holding arms are used to position the filter element and to hold the filter cartridge, and thus clearly define the position of the filter cartridge in relation to the filter head. This makes it possible for the filter element, as previously structurally defined, to have a flow against it. Thanks to the holding arms protruding from the filter element sealing surface, there is a favorable introduction of force. Furthermore, the protruding holding arms protect the filter element sealing surface from damage during transport or during handling / assembly of the filter element. In addition, accumulations of material during production can be prevented.

If a clear rotational position is desired, at least one of the holding arms can be designed differently from the other holding arms, which then engages in a corresponding receiving device on the filter cartridge.

The holding arms can be substantially L-shaped in cross section. The holding arms can also protrude outward in the radial direction with respect to the filter element sealing surface. It can also be advantageous if the holding arms protrude radially outward on the circumferential surface. A particularly advantageous fastening of the filter element to the filter head can be provided by holding arms designed in this way.

The holding arms are preferably firmly connected to the filter element sealing surface, preferably formed in one piece with the filter element sealing surface. This makes it possible to define the position of the holding arms in relation to the filter element sealing surface, which ultimately enables the filter element to be optimally positioned in relation to the rest of the filter.

It is particularly advantageous if the holding arms each have a support surface which points in the opposite direction of the filter element sealing surface, preferably wherein the support surface is convexly curved. The convex curvature of the support surface runs in the axial direction, the support surfaces adjoining the free ends of the holding arms and having a length of at least 3 millimeters and a maximum of 10 millimeters in the radial direction. This enables a particularly advantageous transmission of force between the holding arms and the filter element sealing surface. The holding arms are also made easier to receive in a corresponding recess. In addition, centering ramps can be provided at the transition between the holding arms and the circumferential surface. The centering ramps go here at an angle between 70 ° and 5 °, preferably between 20 ° and 40 °, to the central axis from the circumferential surface in the direction of the holding arms. The centering ramps connect the circumferential surface and the support surfaces to one another. The positioning of the filter element relative to the filter head and in the filter sleeve is facilitated by the centering ramps or centered in the filter sleeve and kept at a distance therefrom.

The holding arms can also have an end surface which is located at the exposed end of the holding arms which points in the radial direction away from the circumferential surface. The distance between the center of the filter element sealing surface and the end surface in the radial direction is preferably between 12 and 18 millimeters, and the distance from the center of the filter element sealing surface can also be between 14 and 16 millimeters. The smallest distance between the filter element sealing surface and the support surfaces in the axial direction is between 0 and 4 millimeters, preferably between 1 and 2 millimeters. The greatest distance between the filter element sealing surface and the support surfaces is between 4 and 6 millimeters. This dimensioning of the holding arms ensures a particularly stable fit of the holding arms in a corresponding recess. Furthermore, the end surfaces serve as a grip area for removing the filter elements from the surrounding filter sleeve and thus make it easier to change the filter elements.

Furthermore, the filter element can be designed in such a way that essentially only axial forces act on the filter element sealing surface, preferably with the holding arms forming an abutment against the axial forces. The axial forces are created here by the compression of the sealing body, which rests on the filter element sealing surface. The holding arms can be flexible in the axial direction and serve as a compensating element between the sealing body and the receiving devices for the holding arms.

In addition, the sealing body rests against the (circular) ring-shaped filter element sealing surface of the filter element in such a way that the sealing body has an outer space is located outside the filter element, separates from an interior space, which is located inside the filter element, between the filter head and the filter element. This results in the separation of a clean gas space from a raw gas space and a particularly advantageous connection between the filter element and the filter head is created.

As a further design feature, a substantially tubular filter sleeve with an open filter sleeve face facing the filter head and a filter sleeve outside running along the jacket surface can be provided, preferably with the filter sleeve surrounding the filter element and delimiting it from the surroundings. In addition, the filter sleeve end face can have receiving devices for the holding arms, the filter element only being in contact with the filter sleeve via the retaining arms arranged in the receiving devices and otherwise being designed to be freely suspended in the filter sleeve. Such a connection between the filter head, filter cartridge and filter sleeve can be implemented with particularly few additional parts and via simple geometries and therefore particularly inexpensively.

The receiving devices can be formed at least by continuous incisions that begin at the filter sleeve end face and run radially to the central axis; the receiving devices preferably receive the holding arms. Among other things, the ends of the incisions can form abutments that are concave in shape to match the convex support surfaces of the holding arms. Here, the abutments absorb the forces that result from the compression and the pressure load on the sealing body. This interaction between receiving devices and holding arms enables particularly simple positioning of the filter element, with compensation for dimensional deviations in addition to the sealing body being created at the same time.

The sealing body can be an axially acting seal. In addition, the filter sleeve can seal against 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 designed in the shape of a pot and accordingly closed at the end facing away from the filter head. This form of sealing enables on the one hand, a simple assembly of the filter cartridge and, on the other hand, can be implemented in a particularly space-saving manner.

At least two of the receiving devices can be designed as receiving locking devices, which are used to receive the holding arms and to receive retaining bolts. These retaining bolts are preferably attached to the filter head and can be aligned radially to the central axis.

The receiving locking devices are advantageously designed in such a way that the retaining bolts interact with the receiving locking devices in the manner of a bayonet lock. Such a configuration enables the filter element to be changed particularly easily, while at the same time enabling sufficient axial movement to brace the sealing body.

For the implementation of the bayonet lock, the receiving locking devices can have a fastening extension in addition to the axial incisions of the receiving devices, which is preferably formed by a further incision which extends from the axial incisions and runs essentially in the circumferential direction around parts of the filter sleeve. In addition, the fastening extension can have a snap-in undercut which is formed by an indentation on the filter head side in the end region of the fastening extension. A bayonet lock designed in this way is particularly cost-effective to manufacture and enables the filter sleeve to be fastened particularly securely to the filter head, which is secured by the snap-in undercut when pressure is applied to the filter.

Another embodiment relates to a filter with at least two filter stages. The filter elements have different filter properties, for example. The sealing arrangements for sealing between the filter elements and the filter heads are preferably designed essentially in the same way. Additionally or alternatively, the receiving devices of the filter sleeves and the holding arms of the filter elements can be designed essentially in the same way. In such a filter, both the seals between the filter element and the filter head, as well as the sealing surfaces on the filter element side and the sealing surfaces on the filter head side, the receiving devices of the filter sleeves or the flap arms of the filter elements of the different filter stages can be designed the same.

Such a filter element or the sealing arrangement between the filter element and the filter head is designed so that the filter element or the sealing arrangement can be subjected to a higher pressure from the outside than from the inside. Preferably, at least one of the filter elements or one of the sealing arrangements of the entire filter is reversely pressurized. As a result, a uniform structure of the different filter stages can be provided. Furthermore, with this structure, the filter elements can be loaded or flowed through both 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 another filter element from the outside to the inside, that is to say towards the central axis.

Such a sealing arrangement can be used in particular in the area of compressed air filters, for example as part of a filter with a plurality of filter stages, for a fluid-tight seal between a filter element and a filter head. Such a filter element is preferably a filter cartridge.

This sealing arrangement comprises an annular elastic sealing body, a filter head and filter element sealing surface. The sealing body has a filter head side facing the filter head sealing surface, an opposite filter element side facing the filter element sealing surface, an inner surface encircling the inside and an opposite outer surface encircling the jacket surface. The filter head side comprises a circumferential first indentation between the inner surface and the outer surface, the filter element side having a circumferential second indentation between the inner surface and the outer surface. The filter head side rests circumferentially, at least in some areas, on the filter head sealing surface, the filter element side in at least in certain areas rests circumferentially on the filter element sealing surface. The filter head sealing surface and the Filter element sealing surfaces consist at least of a circumferential inner partial surface and a circumferential outer partial surface.

The partial surfaces of the filter head sealing surface and the partial surfaces of the filter element sealing surface rise towards the center between the partial surfaces in such a way that the distance between the inner partial surfaces from the inside to the outside and the distance between the outer partial surfaces from the outside to the inside, essentially in the direction of the central axis of the sealing body , decreases. The partial surfaces interact with the indentations in such a way that the sealing body, when pressure is applied, wedges from the inner surface and / or the outer surface, in the direction of the acting force, between the inner partial surfaces and / or the outer partial surfaces.

The partial surfaces increasing towards the center create a central constriction between the filter head sealing surface and the filter element sealing surface, which widens outward on both sides from the center between the two partial surfaces. This constriction interacts with a corresponding tapering of the sealing body. If the sealing body is subjected to pressure from the inner surface or the outer surface, it is pressed against the inclined flanks of the constriction, which are on the side where the force is applied. The sealing body is so inflexible that, when used as intended, it cannot be compressed by the application of pressure to such an extent that the sealing body is pressed through the constriction in the direction of the action of the force.

The fact that the sealing body is pressed into the constriction results in wedging or greater compression of the sealing body between the opposite sealing surfaces, which in turn leads to an increase in the sealing effect. This arises both when there is a resulting application of pressure on the part of the outer circumferential surface and on the part of the inner circumferential surface.

The sealing effect increases automatically with increasing load from the inner surface or the outer surface.

In particular, the sealing seat between the partial surfaces and the indentations is achieved by the pressure difference between the inner surface and the outer surface The interaction between the acting force and the wedge effect is enhanced. If a pressure difference on the inner or outer surface of the sealing body exerts a greater pressure on the sealing body than on the opposite surface, the sealing body is pressed in the direction of the acting force, the space between the partial surfaces being reduced in this direction. The wedge effect results from the interaction between the acting force and the narrowing between the filter head sealing surface and the filter element sealing surface. As a result of the wedge effect, the seal is pressed more strongly against these partial surfaces, whereby the sealing effect increases as the pressure difference increases.

In addition, the ramp-like design makes it easier to position the seal or the filter element in relation to the filter head.

It is particularly advantageous if the sealing body on the filter head side has a circumferential fold groove for receiving a fold element. In particular, the fold element is designed in such a way that, in cooperation with the fold groove, a detachable snap-in connection is created, the snap-in connection holding the filter head side of the sealing body in contact with the filter head sealing surface. Here, the fluted groove runs in the area of the indentation, preferably in the base of the first indentation. The pleat element protrudes between the two partial surfaces of the filter head sealing surface. The pleat element preferably protrudes along a circular ring opposite the filter head sealing surface. By means of such a latching connection, the sealing body can be held reliably on the filter head, with replacement of the sealing body, for example in the event of damage, being particularly facilitated.

It is also particularly advantageous if the second indentation extends at least over half, preferably more than two thirds of the width of the filter element side, between the inner surface and the outer surface. In addition, the first indentation can also extend at least over half, preferably more than two thirds of the width of the filter head side between the inner surface and the outer surface. A particularly good sealing fit can be ensured by such a configuration, since two almost linear sealing surfaces are created and thus a susceptible surface pressure is prevented. It is therefore also particularly advantageous if the sealing body does not bear against the filter element sealing surface in a circumferential partial area of the second indentation, preferably in the area of the lowest point of the second indentation. It is particularly advantageous if the sealing body does not bear against the sealing body, at least in some areas, in the area which is closest to the filter head sealing surface. In this way, a first external and a second internal sealing surface can be created which have similar sealing properties, whereby a comparable load-bearing capacity of the seal on both sides is ensured.

The fold element and the fold groove can be designed in such a way that there is a sealing seat between the base of the fold groove and the area of the fold element which is closest to the filter element sealing surface. This is preferably achieved in that the depth of the fold groove in the axial direction in the non-assembled state of the sealing body is smaller than the folds of the fold element in the axial direction. This makes it possible to produce an annular seal with a small area, which seals in a fluid-tight manner even when the sealing body is slightly pressed.

The locking connection can be formed by a one-sided extension on the folding element and a corresponding recess in the sealing body, the extension protruding outward in the radial direction to a central axis of the sealing body. Here, the opposite side of the folding element has no bulge and is flat in the direction of the central axis. Thus, the pleat element is L-shaped in cross section in the west. A fold element designed in this way ensures that the service life of the sealing body is maximized, since the fold groove is only subjected to external stress.

It is particularly advantageous if the sealing body has a hardness between 60 Shore A and 90 Shore A, preferably between 60 Shore A and 80 Shore A, particularly preferably 70 Shore A. This ensures that the sealing body is elastic enough for a sufficient seal between the sealing surfaces and at the same time is stiff enough to ensure the wedge effect to the required extent. It is also advantageous if partial surfaces of the filter head sealing surface and / or the filter element sealing surface have an internal angle α of less than 180 °, preferably between 130 ° and 170 °, to one another in the radial direction to the central axis. A particularly advantageous range is between 145 ° and 155 °. A particularly advantageous distribution of the forces acting and the creation of the wedge effect can be ensured by these angles.

It is also particularly advantageous if the filter head side of the sealing body has two circular, circumferential sealing partial surfaces, between which the fluted groove extends into the sealing body and both sealing partial surfaces in the radial direction to the central axis at an external angle CM less than 180 °, preferably between 125 ° and 175 °. A particularly advantageous range here is between 140 ° and 150 °. Thus, an optimal interaction between the sealing surfaces on the filter head side and the partial sealing surfaces on the filter head side of the sealing body and thus a high sealing effect and the creation of the wedge effect is guaranteed.

It is also advantageous if the second indentation has a greater depth in the direction of the central axis in the non-assembled state than the flute offset of the partial areas. The vertical offset of the partial area is to be understood here as the distance to which the partial areas extend in the axial direction opposite to the filter head. The height of the partial areas is preferably less than 70% of the depth of the second indentation. The greater depth of the second indentation provides a clearance between the filter head sealing surface and the filter element sealing surface, which compensates for inaccuracies in the positioning of the two surfaces with respect to one another.

In a further particularly preferred exemplary embodiment, the sealing arrangement is designed for use in a filter, the filter element of which is attached to the filter head along an assembly axis which runs parallel to or identical to the central axis of the sealing body. This enables a particularly simple assembly and disassembly of the filter element.

A filter head of a corresponding filter preferably has a hollow cylindrical filter sleeve end face recess which extends from the side of the end face and essentially axially symmetrically to the central axis of the filter element into the filter head extends and receives the filter sleeve face. Here, the filter sleeve end face recess is located in the radial direction to the central axis outside the filter head sealing surface. This enables a particularly compact design.

Furthermore, a corresponding filter head can have two retaining bolt bores extending radially to the central axis, which are preferably opposite one another, the retaining bolt bores receiving retaining bolts which are part of the bayonet lock. A metal-to-metal conical seal is preferably provided between the retaining bolt and the filter head for sealing off from the environment. This design enables particularly simple and inexpensive manufacture.

It can also be of particular advantage if the sealing arrangement is designed in such a way that the inner surface and outer surface of the sealing body do not come into contact with either the filter head or the filter element side. Accordingly, the sealing body seals against the filter head sealing surface and the filter element sealing surface essentially only by means of axially acting forces. Such an axially sealing seal also enables particularly simple assembly and disassembly of the filter element, since a significantly smaller path in the axial direction is necessary in order to achieve a sufficient sealing effect.

Insofar as this is relevant for the corresponding explanation, the above statements basically assume the installed state of the filter element with a pressed sealing body. In this state, the sealing body seals between an interior and an exterior. In the event that a version refers to the dismantled state with the unpressed sealing body, this was explicitly mentioned.

A filter according to the invention can only have the main features as well as any combination of the further features described. Furthermore, the various features of the exemplary embodiments can be combined with one another as desired, even among various exemplary embodiments. Apart from that, the invention relates both to a filter with a described filter element and to a filter with a described sealing arrangement as well as the Sealing arrangement and the filter element per se, or any combination of filter element and sealing arrangement.

The invention is explained below with reference to the figures described. The figures show:

1 shows a detail of a sectional view of a filter stage with a

Sealing arrangement and a filter element,

2 shows a detail of a sectional view of a sealing arrangement,

3 shows an enlarged detail of a sectional view of a sealing arrangement,

4 shows a diagram of the action of forces of an axially and circumferentially loaded sealing body,

5 is a perspective view of a filter element,

6 shows a perspective view of a filter sleeve with a filter element,

FIG. 7 shows a partial section of a bottom view of a filter head and FIG. 8 shows a side view of a multi-stage filter.

1 and 2 show a sealing arrangement 1 for a filter, in particular a compressed air filter, in particular as part of a filter with several filter stages 45, for the fluid-tight seal between a filter element 2, in particular a filter cartridge, and a filter head 3. An annular, elastic sealing body 4 and a filter head and filter element sealing surface 5, 6 are also shown.

The sealing body 4 has a filter head side 7 facing the filter head sealing surface 5, an opposite filter element side 8 facing the filter element sealing surface 6, a circumferential inner surface 9 on the inside and a opposite outer surface 10 running around the circumferential surface. The filter head side 7 has a circumferential first indentation 11 between the inner surface 9 and the outer surface 10, the filter element side 8 likewise having a circumferential second indentation 12 between the inner surface 9 and the outer surface 10.

The filter head sealing surface 5 and the filter element sealing surface 6 consist at least of a circumferential inner partial surface 13 and a circumferential outer partial surface 14. It can be seen from the drawings that the filter head side 7, at least in some areas, is in contact with the filter head sealing surface 5 and the filter element side 8 rests circumferentially, at least in some areas, on the filter element sealing surface 6. The partial surfaces 13, 14 of the filter head sealing surface 5 and the partial surfaces 13, 14 of the filter element sealing surface 6 rise towards the center between the partial surfaces 13, 14 in such a way that the distance between the inner partial surfaces 13 from the inside to the outside and the distance between the outer partial surfaces 14 from the outside to the inside, in the axial direction towards the central axis 18, decreases. It can also be seen that the inner surface 9 and outer surface 10 of the sealing body 4 do not come into contact with either the filter head or the filter element side and accordingly only seal axially with respect to the central axis 18.

Furthermore, a radial seal 46 is shown, which seals the filter between the filter head 3 and the filter sleeve 33 from the surroundings or from the surrounding atmosphere. This seal 46 is a seal 46 which seals off forces acting essentially radially to the central axis 18.

As can also be seen from FIGS. 1 and 2, the partial surfaces 13, 14 cooperate with the indentations 11, 12 in such a way that the sealing body 4, when pressurized, extends from the inner surface 9 and / or the outer surface 10 in the direction the acting force Fi, F2, wedged between the inner partial surfaces 13 and / or the outer partial surfaces 14. The sealing seat between the partial surfaces 13, 14 and the indentations 11, 12 is reinforced by this wedge effect, the action of force Fi, F2 only occurring when there is a pressure difference between the inner surface 9 and the outer surface 10. In Figure 4, the forces are shown which act on the sealing surfaces 5, 6 when the sealing arrangement 1 is loaded on the outer surface Fi. As can also be seen from FIG. 1, the sealing arrangement 1 is designed for use in a filter, the assembly of the filter element 2 on the filter head 3 taking place along an assembly axis which is identical to the central axis 18 of the sealing body 4.

The sealing body 4 rests against the annular filter element sealing surface 6 of the filter element 2 and separates an outer space 31, which is located outside the filter element 2, from an inner space 32, which is located inside the filter element 2, between the filter head 3 and the filter element 2.

In FIG. 3 it is shown that the sealing body 4 has a circumferential fold groove 15 on the filter head side 7 for receiving a fold element 16. The fold element 16 is designed in such a way that, in cooperation with the fold groove 15, a releasable latching connection 17 is created. The latching connection 17 holds the filter head side 7 in contact with the filter head sealing surface 5, the fluted groove 15 running in the area of the indentations 11, 12, preferably in the base of the first indentation 11. The pleat element 16 protrudes between the two partial surfaces 13, 14 of the filter head sealing surface 5. In particular, the pleat element 16 protrudes along a circular ring opposite the filter head sealing surface 5.

The second indentation 12 extends at least over half, preferably more than two thirds of the width of the filter element side 8, between inner surface 9 and outer surface 10. The first indentation 11 extends at least over half, here over two thirds of the width the filter head side 7 between inner surface 9 and outer surface 10.

In a circumferential partial area of the second indentation 12, which is preferably located in the area of the lowest point of the second indentation 12, the sealing body 4 does not lie against the filter element sealing surface 6. As can be seen, the sealing body 4 does not lie in the area which is closest to the filter head sealing surface 5.

As can also be seen from FIG. 3 and also from FIG. 4, the fold element 16 and the fold groove 15 are designed in such a way that between the bottom of the fold shown in FIG Holding groove 15 and the area of the holding element 16 which is closest to the filter element sealing surface 6, there is a sealing seat. This is achieved in that the depth of the retaining groove 15 of the seal in the unmounted state of the sealing body 4 is at least as great as the height of the retaining element 16 in the direction of the central axis 18, preferably less than the height of the retaining element 16.

It is also shown that the latching connection 17 is formed by a one-sided extension 19 on the holding element 16 and a corresponding recess 20 in the sealing body 4. The enlargement 19 protrudes outward in the radial direction to a central axis 18 of the sealing body 4 shown in FIG. The opposite side of the holding element 16 has no bulge and is flat in the direction of the central axis 18. The holding element 16 is essentially L-shaped, which is shown in mirror image in FIG.

The sealing body 4 shown also has a hardness between 60 Shore A and 80 Shore A, preferably 70 Shore A.

In Figure 4 it is shown that the partial surfaces 13, 14 of the filter head sealing surface 5 and the filter element sealing surface 6 in the radial direction to the central axis 18 are at an internal angle α less than 180 °, preferably between 130 ° and 170 ° to each other. Furthermore, the filter head side 7 of the sealing body 4 has two circular, circumferential sealing partial surfaces 23, 24, between which the retaining groove 15 extends into the sealing body 4. Both partial sealing surfaces 23, 24 have an external angle CM smaller than 180 °, preferably between 125 ° and 175 °, to one another in the radial direction to the central axis 18.

Since the sealing body 4 is shown in the compressed state in FIG. 4, it is obvious that the second indentation 12 has a greater depth in the direction of the central axis 18 in the non-assembled state than the partial surfaces 13, 14 towards the center between the two partial surfaces 13 , 14 towards the filter head 3 extend. For example, a compression shown of the sealing body 4 is achieved when the height of the partial surfaces 13, 14 is less than 70% of the depth of the second indentation 12. As can be seen from the force distribution and the exposed inner and outer surfaces 9, 10, the sealing body 4 is an axially acting seal which essentially only seals by means of axially acting forces.

In Figure 5, a corresponding filter element 2 is shown, which is shown here as a filter cartridge. The filter element 2 has a filter element sealing surface 6 which is set back from an end face 21 of the filter element 2. Described differently, the end face 21 is formed by a circumferential collar 22 protruding with respect to the filter element sealing surface 6.

The filter element 2 shown is an exchangeable filter element 2 which can be used to separate particles and / or gases and / or liquids. In particular, it is a filter cartridge that can be designed for use in a filter, in particular a compressed air filter. The filter may be equipped with several filter stages.

The filter element 2 shown comprises an essentially tubular body 27, with an annular end face 21 which faces a filter head 3 shown, inter alia, in FIG. 1 and FIG. The filter element 2 also has an underside 28 which is spaced apart from the end face 21 and faces away from the filter head 3. In addition, the filter element 2 has a circumferential surface 29 which extends along a central axis 18, in particular an axis of rotation. As can be seen, the peripheral surface 29 connects the end face 21 and the underside 28 to one another. Furthermore, in the area of the end face 21, several, preferably three, particularly preferably four, holding arms 30 extending radially to the central axis 18 are shown. An annular filter element sealing surface 6 is provided on the end face 21. The holding arms 30 protrude from the filter element sealing surface 6 and / or from the end face 21.

The holding arms 30 are substantially L-shaped. In addition, the holding arms 30 protrude from the filter element sealing surface 6 and / or the end face 21 in the axial direction and outward in the radial direction, the holding arms 30 protruding radially outward from the circumferential surface 29. As can also be seen from FIG. 5, the holding arms 30 are firmly connected to the filter element sealing surface 6, preferably formed in one piece with the filter element sealing surface 6.

It is also shown that the holding arms 30 each have a support surface 47 which points in the opposite direction of the filter element sealing surface 6. The support surface 47 is convexly curved. The convex curvature of the support surfaces 47 runs in the axial direction to the central axis 18, the support surfaces 47 adjoining the free ends of the holding arms 30, preferably the end surfaces 49, and having a length of at least 2 millimeters and a maximum of 8 millimeters in the radial direction. A length between 3 and 6 millimeters is particularly advantageous. Such a dimensioning allows the filter element 2 to be removed easily and at the same time offers a sufficient support surface 47 as an abutment for the receiving devices 36.

The holding arms 30 have an end surface 49 which is located at the exposed end of the holding arms 30 which points in the radial direction away from the circumferential surface 29, and thus away from the central axis 18. Here, the distance between the center of the filter element sealing surface 6 and an end surface 49 in the radial direction to the central axis 18 is between 12 and 18 millimeters. A distance between the end surfaces 49 and the center of the filter element sealing surface 6 of between 14 and 16 millimeters is particularly advantageous. The distance between the filter element sealing surface 6 and the beginning of the support surfaces 47 in the axial direction is between 0 and 4 millimeters, preferably between 1 and 2 millimeters.

The filter element 2 is designed in such a way that essentially only axial forces act on the filter element sealing surface 6. The holding arms 30 form an abutment 50 with respect to the axial forces that arise as a result of the compression of the sealing body 4 shown in FIG. 1, which rests against the filter element sealing surface 6.

It is particularly advantageous that the holding arms 30 are flexible in the axial direction and thus a compensating element between the one on the filter element sealing surface 6 adjacent sealing body 4 and receiving devices 36 shown in Figure 6 form. The receiving devices 36 receive the holding arms 30.

The filter element 2 has centering ramps 48 at the transition between the holding arms 30 and the circumferential surface 29, which have an angle between 70 ° and 5 ° to the central axis 18 and extend from the circumferential surface 29 in the direction of the holding arms 30. It is particularly advantageous if the angle between the circumferential surface 29 and the centering ramps 48 is between 20 ° and 40 °. The centering ramps 48 connect the circumferential surface 29 and the support surfaces 47 to one another, the centering ramps 48 serving to center the filter element 2 in the surrounding filter sleeve 33.

FIG. 6 shows an essentially tubular filter sleeve 33 with a filter element 2, the filter sleeve 33 having an open filter sleeve end face 34 facing the filter head 3 and a filter sleeve outer side 35 running along the jacket surface. The filter sleeve 33 surrounds the filter element 2 and delimits the interior of the filter from the environment. The filter sleeve face 34 has receiving devices 36 for the holding arms 30, the filter element 2 only being in contact with the filter sleeve 33 via the holding arms 30 arranged in the receiving devices 36 and otherwise hanging freely in the filter sleeve 33.

The receiving devices 36 are formed at least by continuous axial incisions 38 which begin at the filter sleeve end face 34 and run radially to the central axis 18, the receiving devices 36 receiving the holding arms 30. The ends of the incisions 38 form abutments 50 which are concave in shape to match the convex support surfaces 47 of the holding arms 30, the abutments 50 absorbing the pressing force that arises from the pressing of the sealing body 4.

Two of the receiving devices 36 are designed as receiving locking devices 51, which are used to receive the holding arms 30 and to receive the retaining bolts 37 shown in FIG. The retaining bolts 37 are attached to the filter head 3 and aligned radially to the central axis 18. The receiving locking devices 51 are designed such that the retaining bolts 37 in the manner of a Bayonet lock with the receiving locking devices 51 interact.

In addition to the axial incisions 38, the receiving locking devices 51 have a fastening extension 39, the fastening extension 39 being formed by a further incision which extends from the axial incisions 38 and runs essentially in the circumferential direction around parts of the filter sleeve 33. The fastening extension 39 also has a snap-in undercut 40 which is formed by an indentation on the filter head side in the end region of the fastening extension 39.

In FIG. 7, a filter head 3 is shown from the underside, the filter sleeve 33 and the filter element 2 not being shown. The filter head 3 has a filter head sealing surface 5 on which the sealing body 4 shown in FIGS. 1 to 3 rests. As can be seen from the drawing, flap arm recesses 41 are provided which are set back with respect to the filter head sealing surface 5, the flap arms 30 extending into the flap arm recesses 41 in the assembled state.

Furthermore, the filter head 3 has a hollow cylindrical filter sleeve face recess 42, which extends from the filter head sealing surface 5 and essentially axially symmetrically to the central axis 18 into the filter head 3 and, in the assembled state, receives the filter sleeve face 34, the filter sleeve face recess 42 extending in the radial direction to the central axis 18 outside the filter head sealing surface 5 is located.

The filter head 3 also has two folding bolt bores 43 running radially to the central axis 18, which are preferably opposite one another, the folding bolt bores 43 receiving folding bolts 37 which preferably interact in the manner of a bayonet lock with the receiving devices 36 in the filter sleeve 33 from FIG. preferably, a metal-to-metal conical seal 44 being provided between the folding bolts 37 and the filter head 3.

In Figure 8, a multi-stage filter 45 is shown with several filter stages, the filter stages in addition or as an alternative to the sealing arrangement 1 and / or the Filter element 2 include features described above. Here, the multi-stage filter 45 includes, among other things, filter elements 2 with different filter properties. In such a multi-stage filter 45, the sealing arrangements 1 for sealing between the filter elements 2 and the filter heads 3 and / or the receiving devices 36 of the filter sleeves 33 and / or the holding arms 30 of the filter elements 2 can be designed essentially identical to one another in accordance with the above features. In addition, at least one of the filter elements 2 can be subjected to higher pressure from the outside than from the inside, with at least one of the filter elements 2 being conversely pressurized.

Claims

Expectations

1. Filter element (2), in particular exchangeable 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, in particular as part of a filter 45 with several filter stages a substantially tubular body (27) with an annular end face (21) facing a filter head (3), an underside (28) spaced from the end face (21) and facing away from the filter head (3), a circumferential surface (29), which extends along a central axis (18), in particular an axis of rotation,

- wherein the circumferential surface (29) connects the end face (21) and the underside (28) to one another,

- several, preferably four, flap arms (30) extending radially to the central axis (18) are provided in the area of the end face (21),

- An annular, in particular circular, filter element sealing surface (6) being provided on the end face (21), characterized in that the flap arms (30) protrude with respect to the filter element sealing surface (6).

2. Filter element (2) according to claim 1, characterized in that the flap arms (30) are substantially L-shaped and / or that the flap arms (30) opposite the filter element sealing surface (6) in the axial direction and / or in the radial direction outward protrude and / or that the fold arms (30) protrude radially outward on the circumferential surface (29).

3. Filter element (2) according to one of the preceding claims, characterized in that the flap arms (30) are firmly connected to the filter element sealing surface (6), preferably in one piece with the filter element sealing surface (6).

4. Filter element (2) according to one of the preceding claims, characterized in that the flap arms (30) each have a support surface (47) which extends in the opposite direction of the filter element sealing surface (6) preferably wherein the support surface (47) is convex and / or the distance between the filter element sealing surface (6) and the support surfaces (47) in the axial direction is between 0 and 4 millimeters, preferably between 1 and 2 millimeters.

5. Filter element (2) according to one of the preceding claims, characterized in that the flap arms (30) each have an end surface (49) which is located at the exposed end of the respective flap arm (30) which extends in the radial direction from the circumferential surface ( 29), preferably with the distance between the center of the filter element sealing surface (6) and the end surface (49) in the radial direction between 12 and 18 millimeters, preferably with the distance from the center of the filter element sealing surface (6) between 14 and 16 millimeters.

6. Filter element (2) according to one of the preceding claims, characterized in that the filter element (2) is designed such that essentially only axial forces act on the filter element sealing surface (6), preferably wherein the flap arms (30) have an abutment (50) with respect to the axial forces, preferably with the axial forces arising from the compression of the sealing body (4) which rests on the filter element sealing surface (6), preferably with the flap arms (30) being flexible in the axial direction and as a compensating element between the one on the filter element sealing surface (6) adjacent sealing body (4) and receiving devices (36) which receive the flap arms (30).

7. Filter (45) with at least one filter head (3), a filter sleeve (33) and a filter element (2), furthermore a sealing body (4) being provided which is attached to the annular filter element sealing surface (6) of the filter element (2) is applied in such a way that the sealing body (4) has an outer space (31), which is located outside the filter element (2) and inside the filter sleeve (33), from an inner space (32) located inside the filter element (2) between separates the filter head (3) and filter element (2) from one another.

8. Filter (45) according to claim 7, characterized in that the filter sleeve (33) is essentially tubular and has an open filter sleeve end face (34) facing the filter head (3) and one extending along the lateral surface The filter sleeve outside (35) is provided, preferably wherein the filter sleeve (33) surrounds the filter element (2) and delimits it from the surroundings, preferably wherein the filter sleeve face (34) has receiving devices (36) for the flap arms (30), preferably wherein the filter element ( 2) is only in contact with the filter sleeve (33) via the flap arms (30) arranged in the receiving devices (36) and otherwise hangs freely in the filter sleeve (33).

9. Filter (45) according to claim 7 or 8, characterized in that the receiving devices (36) are formed at least by continuous incisions (38) which begin at the filter sleeve end face (34) and run radially to the central axis (18), preferably wherein the receiving devices (36) receive the sheet arms (30), preferably with the ends of the incisions (38) forming abutments (50) which are convexly shaped to match concave support surfaces (47), preferably with the abutments (50) absorbing the pressing force, caused by the compression of the sealing body (4).

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

11. Filter (45) according to one of claims 7 to 10, characterized in that at least two of the receiving devices (36) are designed as receiving locking devices (51) which serve to receive the flap arms (30) and to accommodate the flap bolts (37), which are preferably attached to the filter head (3) and / or aligned radially to the central axis (18), preferably wherein the receiving locking devices (51) are designed in such a way that the folding bolts (37) interact with the receiving locking devices (51) in the manner of a bayonet lock.

12. Filter (45) according to one of claims 7 to 11, characterized in that the receiving locking devices (51) in addition to the axial incisions (38) has a fastening extension (39), preferably wherein the fastening extension (39) is formed by a further incision , of the from the axial incisions (38) and runs essentially in the circumferential direction around parts of the filter sleeve (33), preferably with the fastening extension (39) having a snap-in undercut (40) which is formed by an indentation on the filter head side in the end region of the fastening extension (39) .

13. Filter (45) according to one of claims 7 to 12, characterized in that a sealing arrangement (1) is provided for fluid-tight sealing between the filter head (3) and the filter element (2),

- wherein the sealing arrangement (1) comprises a filter head sealing surface (5) in addition to the sealing body (4) and the filter element sealing surface (6),

- wherein the annular, elastic sealing body (4) has a filter head side (7) facing the filter head sealing surface (5), an opposite filter element side (8) facing the filter element sealing surface (6), a circumferential inner surface (9) and on the inside has an opposite outer surface (10) running around the jacket surface,

- wherein the filter head sealing surface (5) and the filter element sealing surface (6) consist of at least a circumferential inner partial surface (13) and a circumferential outer partial surface (14), the sealing arrangement (1) being designed such that the sealing body (4), when pressure is applied from the inner surface (9) and / or the outer surface (10), in the direction of the acting force, wedged between the inner partial surfaces (13) and / or the outer partial surfaces (14).

14. Filter (45) according to one of claims 7 to 13, characterized in that at least two filter stages, each with a filter head (3), a filter sleeve (33) and a filter element (2) are provided, preferably wherein the sealing arrangements (1) for sealing between the filter elements (2) and filter heads (3), the receiving devices (36) of the filter sleeves (33) and the flap arms (30) of the filter elements (2) of the at least two filters are designed essentially identically.