CN112584913B

CN112584913B - Filter device, filter element and adapter

Info

Publication number: CN112584913B
Application number: CN201980056418.5A
Authority: CN
Inventors: H·贾内克; A·克林泽; A·韦尔; A·克拉万雅
Original assignee: Mann and Hummel GmbH
Current assignee: Mann and Hummel GmbH
Priority date: 2018-08-28
Filing date: 2019-08-16
Publication date: 2023-04-28
Anticipated expiration: 2039-08-16
Also published as: WO2020043511A1; DE102019122099A1; CN112584913A

Abstract

The filter device has a hollow cylindrical filter element and a bypass valve, the valve body of which is arranged on an adapter which is arranged on the end face of the filter element. At least one bypass hole is introduced into the adapter.

Description

Filter device, filter element and adapter

Technical Field

The invention relates to a filter device, in particular a liquid filter device, a filter element for receiving in the filter device and an adapter for arrangement on the filter element.

Background

DE 10 2009 033 263 A1 describes a fuel filter having a hollow-cylindrical filter element which is penetrated radially from the outside to the inside by fuel and is covered at the end by an end disk. For stabilization, a grid-like support body is inserted into the interior of the filter element, in which a bypass valve having a spring-loaded valve body is received, which closes off the outflow opening of the cylindrical interior in one of the end disks in normal filter operation. In this state, unfiltered fluid flows radially through the filter element from the outside to the inside and is discharged from the cavity axially through the side axially opposite the bypass valve. If the flow resistance is too high due to contamination of the filter element, the bypass valve opens so that the unfiltered fluid can reach the clean side directly, bypassing the filter element.

A similar liquid filter is also described in EP 1,199,93 A1, which likewise shows a bypass valve in the interior of a hollow-cylindrical filter element, the valve body of which is acted upon by a force from a spring element toward an opening in the end disk of the filter element.

Disclosure of Invention

The object of the invention is to design a filter device with a hollow-cylindrical filter element and an integrated bypass valve in a manner that is simple in design and can be used in a number of ways.

This object is achieved with the filter device, the filter element and the adapter according to the invention. The preferred embodiments show suitable improvements.

In a preferred embodiment, a filter device is therefore proposed, which has a hollow-cylindrical filter element which is accommodated in a filter housing, can be flowed through in a radial direction by a fluid to be purified, surrounds a purification-side cavity and has an axial end disk, wherein an adapter which is preferably formed separately from the end disk is arranged on the end side of the filter element, which adapter is further preferably connected to the end disk in a sealing manner when the filter element is installed in the filter housing and in a sealing manner in operation, and which adapter has at least one bypass opening which can be closed by a valve body for bypassing the filter element, wherein the adapter comprises a bypass valve with a valve body, wherein the valve body closes the bypass opening and opens against a spring force and releases the bypass opening when a predetermined pressure difference is present. The bypass opening is preferably arranged in an adapter body which forms the main component of the adapter and supports the other functional components and can provide a sealing surface or seal which seals against the filter element and/or the housing.

The filter device according to the invention is used for filtering fluids, preferably liquids such as lubricating oil or fuel. The filter device can also be used for filtering gaseous fluids, if necessary. The filter device has a hollow cylindrical filter element which is accommodated in a filter housing and through which a fluid to be purified flows in the radial direction. Preferably the flow direction is generated radially from the outside inwards.

The inner cavity in the filter element forms a flow chamber which represents a clean side in the radial direction from the outside to the inside, from which the cleaned fluid flows out in the axial direction. The two opposite end faces of the filter element are each covered by an end disk, wherein a flow opening is introduced into at least one end disk for the axial transfer of the purified fluid to an outlet opening from the filter device. The filter medium body of the filter element is designed, for example, as a pleated filter and is composed of paper or nonwoven.

Preferably, a bypass valve or a bypass valve is integrated into the filter system at the adapter, the valve body of which is acted upon by a force by a spring element into the closed position. In normal operating mode, the bypass valve is closed: the valve body closes a bypass opening between an inner cavity in the filter element and a space for unfiltered fluid, the so-called unfiltered fluid, which encloses the filter element. If the pressure in the unfiltered fluid rises above a threshold value relative to the pressure on the clean side, for example if the filter element is blocked, the valve body is adjusted from the closed position into the open position against the force of the spring element acting thereon, whereby the bypass is released and the unfiltered fluid can flow directly from the unfiltered side to the clean side bypassing the filter medium body. In the normal mode, the bypass valve is closed during normal filtration operation at a pressure in the unfiltered fluid below a threshold value, whereby unfiltered fluid flows through the filter media body of the filter element.

The adapter is preferably arranged on the end face of the filter element, which is preferably formed separately from the end disk and has an adapter body as a main or supporting component, wherein the adapter body of the adapter supports the bypass valve such that the adapter body and the bypass valve together form at least one assembly (i.e., adapter), wherein the bypass valve or the valve body of the bypass valve is arranged on the adapter body. Preferably, the adapter body forms a valve seat against which the valve body of the bypass valve or of the bypass valve seals in the closed state. The adapter can limit the adjustment travel of the valve body in the closed position of the valve. The adapter body furthermore has a flow connection section, by means of which the interior space in the hollow-cylindrical filter element can be connected to a connection line or connection piece for a fluid. Whereby the adapter has a dual function: the adapter is connected to the valve body of the bypass valve as a unit, wherein the valve body is acted upon by a force from the spring element toward the bypass opening in the adapter, and the flow is guided between the interior in the filter element and the connecting line by the flow connection section of the adapter. The bypass opening in the adapter body is preferably located radially outside the flow connection section.

Thanks to this construction of the adapter, in the normal mode, when the bypass valve is closed, a flow guidance can be performed and through the bypass valve a flow guidance can be performed on the same end side of the filter element. In this way, the filter device can be used as an oil filter, for example, in a suspended position, with its end projecting, for example, into an oil sump in the vertical extension of the longitudinal axis of the filter, without the risk of: the severely contaminated oil passes from the bottom of the oil sump directly from the unfiltered side to the clean side when the bypass valve arranged at the upper end of the oil filter is opened. The bypass valve is adjacent to the upper end disk of the filter element. When the filter element is penetrated radially from the outside to the inside, the interior space in the hollow-cylindrical filter element forms a clean side, from which the cleaned fluid is discharged during normal operation via the flow connection section of the adapter.

The adapter is arranged on the end face of the filter element and overlaps the cavity lying inside. The flow connection section preferably extends as a pipe connection in the axial direction and can be used to connect a further line through which the purified fluid can be discharged. The pipe connection advantageously accommodates a circumferential sealing element for a flow-tight connection to another pipe or counterpart. The sealing element can be configured as an O-ring, a rectangular seal or a sealing lug. As the material, for example, an elastomer or a nonwoven fabric can be used. Alternatively, the sealing element can also be formed directly on the pipe connection or integrally with the adapter material, for example by means of a two-component injection molding process.

At least one, advantageously a plurality of bypass openings in the adapter body or in the adapter at the end face are preferably located in the radial direction inside the diameter of the inner cavity in the filter element, so that a direct flow connection exists between the space surrounding the end face of the filter element and the inner cavity as the valve body opens. The bypass opening is located at the same time in the region of the outer diameter of the outlet pipe connection in the radial direction or completely outside the pipe connection. In a preferred arrangement, the plurality of openings are arranged annularly around the pipe joint at radial intervals. With the valve body open, unfiltered fluid flows through the bypass opening into the cavity, and unfiltered fluid can be discharged from the cavity in the axial direction via the nipple on the adapter.

The valve body is held, for example, in a form-fitting manner on the adapter body or on a lower part of the bypass valve connected to the adapter body, for example, clamped onto the adapter body or the lower part, wherein an axial relative movement of the valve body is possible for enabling an opening and closing movement.

The adapter is fitted onto the end face of the filter element and engages in a fluid-tight and fluid-tight manner with a cavity in the filter element. According to an advantageous embodiment, the adapter or the adapter body simultaneously forms one of the end discs of the end side; in this case, the adapter body can be bonded or glued to the end face of the filter element. In an alternative embodiment, the adapter can be connected to the end disk of the filter element in a non-releasable manner, in particular by being welded to the end face of the filter element, for example by means of mirror welding.

However, an embodiment of the adapter and the end disk is also possible, wherein the individual adapter or the adapter body completely or partially overlaps the end disk in the radial direction. A sealing element or nonwoven loop can be arranged between the end disk on the end face of the filter element and the fitted fitting or fitting body, which sealing element or nonwoven loop is arranged directly adjacent to the flow opening in the end disk and thus to the cavity in the filter element. The sealing element or the nonwoven loop can optionally have an L-shaped cross section and protrude axially into the cavity. The sealing element or nonwoven loop prevents that a fault flow between the end disk and the adapter may occur between the environment and the cavity in the normal mode. The sealing element or the nonwoven loop can also optionally be formed as an adhesive layer with which the adapter is glued to the end face of the filter element.

In an advantageous embodiment, the adapter has means for a form-locking connection, in particular a releasable and non-releasable snap connection, with the housing. For this purpose, a projection, such as a lug or a spacer, on the housing in the region of the outlet thus cooperates with a catch on the adapter in order to prevent or impede the adapter from being pulled out of the outlet. The connection can be designed such that the adapter is either received in the housing without an axial play or alternatively with a predefined axial play, so that the adapter is allowed to move in the housing in the axial direction within a defined range of travel.

In an advantageous embodiment, the filter device has a check valve which is opened by the applied pressure differential during normal operation and which permits unobstructed fluid flow. The non-return valve and the bypass valve are closed when no pressure difference is applied to the filter device, for example when the oil filter of the internal combustion engine is in the motor-stopped state. The filtered fluid cannot return to the unfiltered side.

If the filter element has too great a flow resistance, for example due to contamination, the bypass valve opens.

In the case of maintenance, the filter element moves downwards after opening the cover. By means of the connection of the filter element and the adapter, the adapter is also pulled down until the connection of the housing and the adapter does not allow further movement. The check valve remains closed.

When designing a form-locking connection with an axial play, the seal between the housing and the adapter can be released, so that fluid can flow downstream of the non-return valve.

In a preferred embodiment, the adapter part furthermore has a check valve which is arranged downstream of the bypass valve in or at the pipe connection and which particularly preferably protrudes from the pipe connection into the outlet of the housing upper part.

In an alternative embodiment, a non-return valve is arranged downstream of the bypass valve, wherein a non-return valve seat is formed in the valve body of the bypass valve, so that the unit formed by the bypass valve and the non-return valve can be formed in a particularly space-saving manner, in particular in the axial direction, so that the filter device can be arranged compactly. The check valve seat and the valve body are preferably formed as a unit, in particular the check valve seat and the valve body can be formed in one piece.

In this embodiment, the check valve body is supported by a check valve spring, which is received on the opposite side in a check valve housing, which is connected to the pipe connection, preferably is formed in one piece with the pipe connection. The non-return valve is designed such that it opens in the direction of travel when passing through the filter element and closes, for example, when the oil flow is stopped, in order to prevent backflow in the opposite direction.

In a further advantageous embodiment of the filter device, the check valve spring is supported on the valve body of the bypass valve on the opposite side of the check valve body, so that a possible change in position of the valve body of the bypass valve, which is received in the adapter, has no effect on the switching behavior of the check valve, since the distance between the check valve body and the spring receptacle for the check valve spring on the valve body and the spring prestress of the check valve spring remain unchanged.

A support tube or intermediate tube can be arranged in the filter element, the wall of which has a sufficiently large through-flow opening for a radial through-flow of the filter element not to be impeded. The intermediate tube imparts additional stability to the filter element. At the same time, the intermediate tube can be used to fix and axially support the adapter.

According to a further advantageous embodiment, the intermediate tube has at least one clamping element which protrudes into the cavity of the filter element and which connects the intermediate tube to the filter element in a form-fitting or force-fitting manner and is fixed to the filter element in the axial direction. For example, a plurality of clamping elements can be formed on the intermediate tube in a circumferentially distributed manner for clamping the intermediate tube to the filter element with a uniform force distribution. The clamping element advantageously engages the end disk in the axial direction and protrudes radially into the filter element or the filter medium body of the filter element.

The clamping element on the adapter applies a radially outwardly directed force to the filter medium body or to the material of the end disk which extends axially slightly into the material of the filter medium body.

The filter device can be constructed as a two-part structure by: the housing component forms a first structural unit with the intermediate tube and the filter element and the adapter forms a second structural unit with the bypass valve, wherein the two structural units can be assembled during the first installation and then assembled into the filter device by connection to the housing upper part.

The unit pre-assembled with the invention can be prefabricated before the filter device is assembled. It is thus possible to provide a unit of a fitting set consisting of adapter piece and bypass valve and optionally check valve and filter element, which unit is first connected to a cover and then screwed into the housing part together with the cover.

If there is a sufficient axial play between the adapter and the housing in the region of the connection, the unit formed by the housing cover, the filter element, the adapter with bypass valve and optionally the check valve can be clamped into the housing in a first step and secured against falling out before the cover is screwed onto the housing in a second step and the filter device is closed.

Drawings

Further advantages and suitable embodiments can be gathered from the preferred embodiment, the description of the figures and the figures. Wherein:

fig. 1 shows a section through the components of a filter device, which is formed as an oil filter, after assembly, with a hollow-cylindrical filter element and with a housing component for receiving and with an intermediate tube, wherein an adapter with a bypass valve and a check valve is fitted onto the filter element on the end face;

fig. 2 shows a cross section of a slightly modified embodiment of the filter device of fig. 1;

fig. 3 shows an alternative embodiment, in which a non-return valve is arranged in the adapter of the filter device.

In the drawings, like elements are provided with like reference numerals.

Detailed Description

Fig. 1 and 2 show a filter device 1 embodied as an oil filter, which has a housing part 2 embodied as a cover, which is part of a filter housing and is screwed into a housing upper part 200 from below. Furthermore, a filter element 3 is provided which can be inserted into the housing component 2 and is configured as a hollow cylinder and is penetrated radially from the outside to the inside by the fluid to be purified. The filter element 3 has an inner cavity 4, which forms the clean side of the filter element.

End discs

5, 6 are located on both end sides of the filter element 3, which end discs axially flow-tightly close the filter medium body of the filter element 3. The filter medium body is preferably embodied as a star-folded bellows made of paper or nonwoven.

The housing component 2 is designed as a screw-in unit which forms a cover and has external teeth which allow the housing component 2 to be screwed into the housing upper part 200 from below. In the bottom region of the housing component 2, an overflow screw 7 is preferably present, which is furthermore preferably in flow connection with the cavity 4 in the filter element 3 in the installed state. With unscrewing of the overflow hole screw 7, oil that has accumulated in the housing member 2 and in the cavity 4 can be discharged. In the installed state, the filter device 1 assumes the position shown in the drawing, in which the filter longitudinal axis 8 extends at least approximately in the vertical direction.

Furthermore, the filter device 1 comprises a central tube 9 which, in the installed state, protrudes into the cavity 4 of the filter element 3 and additionally stabilizes the filter element. The intermediate pipe 9 rests against the inner wall of the cavity 4 and has a large flow opening through which fluid can pass when flowing through the filter element. The intermediate tube 9 is clamped to the bottom of the housing component 2, for example by means of a latching mechanism.

An adapter with an adapter body 14 is fitted onto the upper end face of the filter element 3, said adapter preferably being connected in a sealing manner to the upper end disk of the filter element 3 in the ready-to-operate state. As shown in the figures, the upper end disk 5 preferably has a radial sealing surface (no reference sign) radially inwards, which in addition preferably rests sealingly against a cylindrical sealing abutment surface (no reference sign) of the adapter body 14 as shown. The adapter is equipped with a bypass valve 10 which, in the open state, connects the unfiltered side directly to the clean side, so that the fluid passes directly into the cavity 4 bypassing the filter medium body. The bypass valve 10 comprises a valve body 11 which is clamped in an axially adjustable manner on the intermediate pipe 9 and a spring element 12, for example as a valve spring, which is preferably and as shown in the drawing is supported on a lower part 21 of the bypass valve 10 and axially charges the valve body 11 in the direction of the closed position. Alternatively, the spring element can be formed integrally with a valve body made of an elastic material. The lower part 21 is furthermore preferably locked to the adapter body 14 by means of a hook-shaped section 13 with a radially outwardly directed hook-shaped lug, as shown in the drawing, by: the hook-shaped portion 13 engages behind a circumferentially extending support 35 on the adapter body 14. This allows the valve body 11 to perform an axial adjusting movement relative to the adapter body 14 between its closed position and its open position, while the valve body 11 is clamped in an anti-lost manner on the adapter body 14 in the axial direction. In the installed state, the valve body 11 and the spring element 12 are preferably located in the cavity 4 of the filter element 3, as a result of which the installation space requirement is minimized.

The adapter comprises the adapter body 14 as shown and, on the one hand, the bypass valve 10 as a structural or assembly unit and, on the other hand, a pipe connection 15, which is preferably formed in one piece and is of uniform material, on the adapter body 14, which establishes a flow connection between the cavity 4 in the filter element 3 and a discharge line or discharge pipe to be connected to the pipe connection 15. The adapter body 14 rests, for example, on the upper end disk 5 of the filter element 3 and optionally covers the end disk 5 at least partially, if necessary completely. The adapter element which closes the cavity 4 upwards has a bypass opening 16 which is located in the region of the outer circumference or radially outside the pipe connection 15 which extends in the axial direction, but radially within the diameter of the cavity 4. Through the bypass hole 16 in the adapter body 14, the cavity 4 can communicate with the surrounding space.

The bypass opening 16 in the adapter body 14 is closed off in normal operation by the valve body 11, which has a central recess 17, through which the cavity 4 communicates with the pipe connection 15, but is formed on its end face in accordance with the form of an annular gasket, wherein the gasket bears axially against the inner face of the adapter body 14 and closes off the bypass opening 16. The valve body 11 preferably has a likewise annular gasket-like valve sealing ring 22 as shown in the drawing for abutting against the adapter and for sealingly closing the bypass opening 16. The valve seal 22 can be formed of an elastomer or a nonwoven fabric, for example. If the pressure in the unfiltered fluid on the outer side of the filter element 3 exceeds a limit value or a threshold value (for example if the filter element is blocked), the valve body 11 is placed in the open position in the axial direction by the unfiltered fluid against the force of the spring element 12 acting thereon, after which the unfiltered fluid can flow into the cavity 4 in the filter element 3 via the open bypass opening 16 and be discharged therefrom via the pipe connection 15.

The intermediate tube 9, which is preferably separable from the filter element 3 but can also be formed integrally as part of the filter element 3, has a cylindrical sealing contact surface (no reference sign) on the side axially opposite the tube connection 15 and, if it adjoins it, preferably has a clamping element 18 which protrudes into the cavity 4 and directly contacts the inner wall of the filter element 3, which defines the filter medium body of the cavity 4. The clamping element 18 has a clamping lug on its radially outer side, which protrudes beyond the material of the lower end disk 6 and hooks there. In this way, the filter element 3 is reliably clamped in its axial position on the intermediate tube 9. As shown in the figures, the lower end disk 6 preferably has a radial sealing surface (no reference sign) radially on the inside, which sealing surface rests sealingly against a cylindrical sealing abutment surface (no reference sign) of the intermediate pipe 9.

If necessary, the intermediate tube 9 can be connected to the filter element by means of adhesive bonding, wherein in this case the clamping element 18 can be dispensed with.

If necessary, immediately adjacent to the opening of the cavity 4, an annular sealing element or nonwoven can be fitted onto the upper end disk 5 for supporting a radial sealing surface (sealing element not shown in the drawing).

The intermediate pipe 9 has an end which sealingly closes the lower end disk 6 and which has a particularly central outlet pipe connection with a preferably outwardly directed radial seal 71. The outlet screw 7 sealingly closes the housing part 2 with a screw-side radial seal 72 which radially inwardly bears against a cylindrical sealing abutment surface of the housing part 2. The outlet screw preferably has a central cylindrical recess which opens into the interior of the housing and which receives the outlet pipe connection of the intermediate pipe 9 and provides a hollow cylindrical sealing abutment for the intermediate pipe-side radial seal 71. The screw-side radial seal 72 is preferably arranged axially at the level of the sealing contact surface for the intermediate tube-side radial seal 71.

An external sealing ring 20 is fitted onto the pipe connection 15 of the adapter body 14, said sealing ring being inserted into a circumferential groove on the pipe connection 15. The pipe connection 15 is inserted in a sealing manner into the outlet 101 of the housing upper part 200, wherein a fluid-tight or fluid-tight connection between the pipe connection 15 or the adapter body 14 and the housing upper part 200 is ensured by the sealing ring 20. Alternatively, the inner sealing ring on the housing part upper part 200 can be sealed against the pipe connection 15 or the adapter body 14.

Furthermore, the adapter preferably comprises a non-return valve 40, as shown in fig. 1 and 2, which is arranged downstream of the bypass valve 10 on the clean side and in or at the pipe connection 15 and preferably extends from the pipe connection 15 into the outlet 101, as shown in fig. 1 and 2. For this purpose, the pipe connection 15 preferably has a check valve seat 44 at its axial end facing away from the filter element 3, against which the check valve body 41 rests in a sealing manner by means of a check valve spring 42, which is supported on the opposite side by a check valve cover 43 connected to the pipe connection 15. The non-return valve 40 is designed such that it opens in the direction of travel when passing through the filter element 3 and closes, for example, when the oil flow is stopped, in order to prevent backflow in the opposite direction.

In an alternative embodiment of the filter device 1 according to fig. 3, a check valve 40 is arranged downstream of the bypass valve 10 on the clean side, wherein the check valve seat 44 is arranged in the valve body 11 of the bypass valve 10. The check valve body 41 rests sealingly against a check valve seat 44 by a check valve spring 42, which is supported on the opposite side by a check valve cover 43 connected to the pipe connection 15, preferably formed in one piece with the pipe connection 15. In this embodiment, the non-return valve 40 is arranged in a space-saving manner inside the adapter part and is designed such that it opens in the direction of travel when passing through the filter element 3 and closes, for example, when the oil flow is stopped, in order to prevent backflow in the opposite direction.

In a further embodiment of the filter device 1, which is not shown here and is similar to the embodiment shown in fig. 3, the check valve spring 42 is supported on the valve body 11 of the bypass valve 10 on the opposite side of the check valve body 41, so that a possible change in position of the valve body 11 of the bypass valve 10 received in the adapter has no effect on the switching behavior of the check valve 40, since the distance between the check valve body 41 and the spring receiver for the check valve spring 42 on the valve body 11 and thus the prestress of the check valve spring 42 remains unchanged.

The adapter, in particular the adapter body 14, preferably has at least one catch 31 which can cooperate with a lug or a spacer 30 in the outlet 101 in such a way that the adapter is prevented or impeded from being pulled out of the outlet 101.

In the embodiment of fig. 1, the catch 31 is designed such that it holds the adapter in the outlet 101 essentially without axial play. By "without axial play" it is meant in this respect that the position of the adapter does not change so significantly that the sealing ring 20 will come off. The fluid in the outlet 101 is thus also left in the outlet when the filter element 3 is removed, since the adapter is also held sealingly in the outlet by the catch 31. The separation between the unfiltered side and the clean side thus also continues on the adapter when the filter element is replaced. In this embodiment, the bypass valve 10 is also sealed when the filter element 3 is removed during filter element replacement.

In the embodiment of fig. 2 and 3, the catch 31 is designed such that it clamps the adapter in the outlet 101 with an axial play. By "axially clearance" in this respect is meant that the position of the adapter can be varied such that the sealing ring 20 is disengaged when the adapter is moved axially downwards. The fluid present in the outlet 101 can thus flow out of the outlet 101 when the filter element 3 is removed, so that a small amount of fluid remains in the system when it is replaced. A snap-free embodiment is also conceivable, in which case the adapter can be removed together when the filter element 3 is replaced, for example for the replacement of the seal 20, if necessary. The selection between variants can be made application-specifically according to the functional priority.

In the variant shown in fig. 1 to 3, the intermediate tube 9 is preferably connected to the lower housing part 2 by means of a snap connection 32, so that the intermediate tube 9 is pulled out together when the housing part 2 is released. The lower end disk 6 is furthermore preferably designed such that it has a higher holding force in the axial direction relative to the central tube 9 than the upper end disk 5 has relative to the adapter body 14. This can be done, for example, by: the engagement of the radial seal with respect to the cylindrical sealing abutment surface between the lower end disk 6 and the intermediate tube 9 is designed to be more stable than the engagement of the radial seal with respect to the cylindrical sealing abutment surface between the upper end disk 5 and the adapter body 14. Alternatively or additionally, as in the illustrated embodiment, it can be provided that the lower end disk 6 is designed such that it engages behind the clamping element 18.

In the variant shown in fig. 2 and 3, the engagement of the radial seal with respect to the cylindrical sealing abutment surface between the upper end disk 5 and the adapter body 14 is preferably designed such that the holding force in the axial direction, which is caused in particular by friction, is greater than the holding force between the outlet 101 and the seal 20, which is caused in particular by friction. It can thus be ensured that the seal 20 is disengaged during disassembly and that fluid can flow out of the outlet 101.

Claims

1. A filter device having a hollow-cylindrical filter element (3) which is accommodated in a filter housing and can be penetrated in a radial direction by a fluid to be purified, which surrounds a purification-side cavity (4) and has axial end disks (5, 6), wherein an adapter piece which is formed separately from the end disks (5, 6) and has an adapter body (14) is arranged on the end side of the filter element (3), which adapter body can be connected sealingly to the end disk (5) when the filter element (3) is installed in the filter housing and is connected sealingly to the end disk (5) in operation, and at least one bypass opening (16) for bypassing the filter element (3) can be introduced into the adapter body, wherein the valve body (11) closes the bypass opening (16) and opens against an elastic force and releases the bypass opening (16), wherein the adapter piece comprises a valve (10) having the valve body (11),

the adapter also has a non-return valve (40) which is arranged downstream of the bypass valve (10) in the adapter body (14), or

A non-return valve (40) is arranged downstream of the bypass valve (10), wherein a non-return valve seat (44) is arranged in the valve body (11) of the bypass valve (10).

2. The filter device according to claim 1, which is arranged in or at the pipe connection (15) and extends from the pipe connection (15) into the outlet (101) of the housing upper part (202).

3. The filter device according to claim 1 or 2, wherein the adapter body (14) engages with the bypass valve (10) in a flow-tight manner with the cavity (4) in the filter element (3) and has a flow connection section (15).

4. A filter device according to claim 1 or 2, characterized in that the adapter is sealingly connected to the upper end disk (5) of the filter element (3) in a releasable or non-releasable manner.

5. The filter device according to claim 1 or 2, characterized in that the adapter covers at least partially the end side of the filter element (3).

6. The filter device according to claim 1, characterized in that the flow connection section of the adapter is configured as a pipe joint (15) extending out in the axial direction.

7. A filter device according to claim 6, characterized in that a sealing ring (20) is fitted or a sealing geometry is formed onto the pipe joint (15).

8. A filter device according to claim 1 or 2, characterized in that an intermediate tube (9) which is formed separately from the filter element (3) and serves to radially support the filter element (3) protrudes into the filter element (3).

9. The filter device according to claim 8, characterized in that the intermediate tube (9) has at least one clamping element (18) which protrudes into the cavity (4) of the filter element (3) and which has a radially outwardly directed clamping force for clamping the underlying end disk (6).

10. The filter device according to claim 9, characterized in that the clamping element (18) axially abuts the end disk (6) and protrudes radially into the filter medium body of the filter element (3).

11. A filter device according to claim 1 or 2, characterized in that the valve body (11) is fixed to the adapter element in a form-fitting manner in the axial direction.

12. A filter device according to claim 11, characterized in that a spring element (12) is loaded to the valve body (11), which spring element is supported on the adapter.

13. A filter device according to claim 1 or 2, characterized in that a sealing element or a nonwoven loop is arranged or formed between the end disc (5, 6) and the adapter.

14. A filter device according to claim 1 or 2, characterized in that the end disk (5) is connected to the adapter in a sealing and undamaged or undamaged releasable manner.

15. The filter device of claim 1, wherein the filter device is a liquid filter device.

16. The filter device according to claim 4, characterized in that the adapter body (14) is welded or glued sealingly to the upper end disk (5) of the filter element (3).

17. The filter device according to claim 5, characterized in that the adapter body (14) at least partially covers the end side of the filter element (3).

18. The filter device according to claim 6, characterized in that the flow connection section of the adapter body (14) is configured as a pipe joint (15) extending out from the filter element (3) in the axial direction.

19. The filter device according to claim 11, characterized in that the valve body (11) is fixed to the adapter body (14) in a form-fitting manner in the axial direction.

20. A filter device according to claim 12, characterized in that the spring element is supported by a lower part (21) fixed to the adapter or surrounded by the adapter body (14).

21. A filter device according to claim 13, characterized in that a sealing element or a nonwoven loop is arranged or formed on the upper end disk (5).

22. The filter device according to claim 14, characterized in that the end disk (5) is connected to the adapter body (14) in a sealing and undamaged or undamaged releasable manner.

23. Filter element (3) for receiving in a filter device according to one of the preceding claims, which can be penetrated in a radial direction by a fluid to be purified and has an axial end disk (5, 6), wherein an adapter having an adapter body (14) can be arranged on the end face of the filter element (3).

24. The filter element of claim 23, wherein the filter element is a liquid filter element.

25. Adapter for arrangement on a filter element (3) in a filter device according to any one of claims 1 to 22, having a bypass valve (10) with a valve body (11) and an adapter body (14) with at least one bypass opening (16) which can be closed by the valve body (11), wherein the adapter is designed for sealing connection to an end disk (5) of the filter element (3), wherein the valve body (11) closes the bypass opening (16) and opens and releases the bypass opening (16) against a spring force in the presence of a predetermined pressure difference.

26. Adapter according to claim 25, characterized in that the adapter body (14) is designed for sealing connection with an end disk (5) of the filter element (3).