WO2018050238A1

WO2018050238A1 - Filter device, in particular air filter, for a fresh air system of an internal combustion engine

Info

Publication number: WO2018050238A1
Application number: PCT/EP2016/071886
Authority: WO
Inventors: Alexandre LUCHESI DE ALMEIDA; Edson VALDOMIRO DE AZEVEDO JUNIOR; Pedro BASSO; Marcos José DANTAS DE OLIVEIRA
Original assignee: Mahle International Gmbh; Mahle Metal Leve S/A
Priority date: 2016-09-15
Filing date: 2016-09-15
Publication date: 2018-03-22

Abstract

The invention relates to a filter device (1), in particular an air filter, for a fresh air system of an internal combustion engine. The filter device (1) comprises a filter housing (2) which delimits a housing interior space (3). Furthermore, the filter device (1) comprises a filter element which is arranged in the housing interior space (3) and divides the housing interior space (3) into a raw side and a pure side. Moreover, the filter device (1) comprises a flow guiding device (8) which has flow guiding elements (9), is arranged in the housing interior space (3), and is fastened or can be fastened releasably to an inner side (10) of the filter housing (2).

Description

Filter device, in particular air filter, for a fresh air system of an internal combustion engine

The invention relates to a filter device, in particular an air filter, for a fresh air system of an internal combustion engine, and to an internal combustion engine having a filter device of this type.

An air filter of the generic type is known, for example, from DE 27 567 51 A1 and comprises a filter housing which has a housing pot, a housing cover, an air inlet for introducing raw air into the filter housing and an air outlet for discharging the pure air from the filter housing. Furthermore, the air filter comprises a filter element which is arranged exchangeably in the filter housing and, therein, separates a raw side which is connected fluidically to the raw air inlet from a pure side which is connected fluidically to the pure air outlet. Flow guiding elements are typically formed integrally on the inner side on the filter housing, which flow guiding elements can improve the flow behavior of the raw air which flows through the raw side, in particular directly after the passage through the raw air inlet.

It proves disadvantageous here that, depending on the application of the filter device, different requirements arise for influencing the raw air flow by means of suitable flow guiding elements. Therefore, in conventional filter devices, the filter housing has to be manufactured individually with different flow guiding elements which correspond to the desired requirement profile, that is to say an individually configured filter housing has to be manufactured for every application. This proves complicated and is therefore associated with high manufacturing costs.

The present invention is concerned with the problem of specifying an improved embodiment for an air filter of the type mentioned at the outset or for an associat- ed filter element, which embodiment is distinguished, in particular, by improved flexibility in terms of the flow optimization which is achieved in the raw air in the raw side.

This object is achieved by way of the subject matter of the independent patent claims. Preferred embodiments are the subject matter of the dependent patent claims.

Accordingly, it is a basic concept of the invention to equip a filter device, in particular an air filter for a fresh air system of an internal combustion engine, with a flow guiding device for flow optimization of the raw air which is introduced into the filter device. According to the invention, the flow guiding device can, at least during first assembly, be fastened in a releasable way to the filter housing.

Such a modular construction of this type of the filter device allows the filter device to be equipped with differently configured flow guiding devices in an application- specific manner. In comparison with conventional filter devices, in which the flow guiding device is connected fixedly, that is to say non-releasably, to the filter housing, the filter device according to the invention which is presented here can be adapted with high flexibility to different requirement profiles.

After first mounting of the flow guiding device, the device can, if desired, be fixed permanently to the filter housing. In preferred embodiments, the flow guiding device is glued or welded to the housing after the first assembly, so that a non- releasable connection is built.

A filter device according to the invention, in particular an air filter, for a fresh air system of an internal combustion engine comprises a filter housing which delimits a housing interior space. A filter element with a filter body made from filter materi- al is arranged exchangeably in the housing interior space, which filter element divides the housing interior space into a raw side and a pure side. Moreover, the filter device comprises a flow guiding device which is arranged in the housing interior space and has flow guiding elements. The flow of the raw air which is introduced into the housing interior space and is to be cleaned can be optimized by means of the flow guiding elements. At the same time, said flow guiding elements can assume the function of a pre-separator (also known to a relevant person skilled in the art as a "cyclone separator") which separates dirt particles which are present in the raw air out of the air flow before the actual filter element is flowed through. According to the invention, the flow guiding device is fastened releasably to the filter housing. This makes a modular realization of the filter device possible, with the result that various flow guiding devices with different flow guiding elements can be installed in the filter housing in an application-specific manner.

In one preferred embodiment, at least one receiving element is arranged on the inner side of the filter housing, to which receiving element the flow guiding device is fastened or can be fastened releasably. This makes a stable attachment of the respective flow guiding device to the filter housing possible. A plurality of receiving elements of this type are particularly preferably provided, as a result of which particularly stable mechanical fastening of the flow guiding device can be ensured.

The at least one receiving element can expediently be configured as a receiving rail which extends along an axial direction of the filter housing. The flow guiding device can be pushed into an at least one receiving rail of this type for releasable fastening to the filter housing. This makes a comfortable introduction of the flow guiding device into the housing interior space possible, including simple mounting on the filter housing. The same applies to the dismantling of the flow guiding device if the latter is to be removed from the housing interior space again. The at least one receiving rail particularly expediently projects inward from the inner side of the filter housing, into the housing interior space. This measure facilitates pushing of the flow guiding device into the receiving rail/rails.

In a further preferred embodiment, an air inlet for introducing raw air to be cleaned is configured in the filter housing. In said embodiment, the flow guiding device is arranged in the region of the air inlet on the inner side of the filter housing. In this way, a situation is achieved where the raw air to be cleaned onto the flow guiding elements of the flow guiding device immediately after the introduction into the housing interior space, as a result of which a pre-separation of dirt particles can be brought about.

In one advantageous development, the air inlet has an aperture which is configured in the filter housing and is covered at least partially, preferably completely, in an opaque manner with regard to a viewing direction along a radial direction of the filter housing by the flow guiding device which is fastened to the filter housing. It is ensured in this way that the entire raw air which is introduced via the air inlet into the raw side of the housing interior space comes into contact with at least one flow guiding element of the flow guiding device.

In another preferred embodiment, the flow guiding device comprises a main body, on which the flow guiding elements are arranged. This makes a mechanically particularly stable attachment of the flow guiding elements to the filter housing possible.

In one advantageous development, the flow guiding elements can be arranged on the main body in a grid-like manner with at least two grid columns and at least two grid lines. This makes a homogeneous arrangement or distribution of the individual flow guiding elements on the main body possible.

The main body can preferably be provided with the geometry of a cylinder segment. The main body with the geometry of a cylinder segment particularly preferably extends in a cross section perpendicularly with respect to the axial direction along a circumferential direction over an angle of approximately 90°. As an alternative to this, an angle of approximately 180° or of approximately 360° is also conceivable. Main bodies which are configured in this way are familiar to a person skilled in the art as "quarter circle bodies" or "semicircle bodies" or "full circle bodies".

The main body is expediently arranged at a spacing from the circumferential wall of the filter housing. Therefore, the space between the main body and the circumferential wall of the filter housing can be flowed through by the raw air to be cleaned.

In a further preferred embodiment, the flow guiding elements are configured as flow guiding fins which project radially outward from the main body. In another preferred embodiment, the flow guiding elements are arranged in a spiral manner between the main body of the flow guiding device and the circumferential wall of the filter housing. Both abovementioned variants follow the principle of operation of a pre-separator for separating dirt particles from the raw air before the latter flows through the filter element which is equipped with a filter medium from the raw side into the pure side of the housing interior space.

In one advantageous development, the main body has a plurality of fastening struts which project radially outward. At least one mounting rail is attached on at least two fastening struts. Said at least one mounting rail can be pushed into the at least one receiving slide which is configured on the inner side of the filter housing and is of complementary configuration with respect to the mounting rail. This measure makes simple mounting of the flow guiding device on the filter housing possible.

In one advantageous development which makes particularly comfortable pushing of the flow guiding device into the housing interior space possible, the flow guiding device comprises at least two mounting rails which are arranged at a spacing from one another.

The flow guiding device can expediently be fastened releasably to the filter housing by means of a clip or latching connection. This permits simple release of the connection and removal of the flow guiding device from the housing interior space of the filter device.

Furthermore, the invention relates to an internal combustion engine having a fresh air system for introducing fresh air into the combustion chambers of the internal combustion engine. Furthermore, the internal combustion engine comprises a filter device which is present in the fresh air system and has been presented in the above text. The above-described advantages of the filter device are therefore also transferred to the internal combustion engine according to the invention.

Further important features and advantages of the invention result from the subclaims, from the drawings and from the associated description of the figures using the drawings.

It goes without saying that the features which are mentioned in the above text and are still to be described in the following text can be used not only in the respec- tively specified combination, but rather also in other combinations or on their own, without departing from the scope of the present invention.

Preferred exemplary embodiments of the invention are shown in the drawings and will be explained in greater detail in the following description.

In the drawings, in each case diagrammatically: fig. 1 shows one example of a filter device according to the invention in a perspective illustration fig. 2 shows the filter housing of the filter device without a housing bottom with the result that the housing interior space of the filter housing is visible fig. 3 shows a first variant of the flow guiding device of the filter device in a separate, perspective illustration, fig. 4 shows a second variant of the flow guiding device of the filter device in a separate, perspective illustration, fig. 5 shows a detail of the hollow-cylindrical filter housing in a cross section perpendicularly with respect to the axial direction, and fig. 6 shows a variant of the filter housing from figure 2.

Figure 1 shows one example of a filter device 1 according to the invention which can be used as an air filter for a fresh air system of an internal combustion en- gine, in a perspective illustration. The filter device 1 comprises a filter housing 2 which delimits a housing interior space 3. A filter element is arranged in the housing interior space 3, which filter element divides (cannot be seen in the illustration of figure 1 ) the housing interior space into a raw side and a pure side. In the example of the figures, the filter housing 2 has substantially the geometry of a cylinder and comprises a circumferential wall 4, in which an air inlet 5 is configured. The raw air to be cleaned can flow via the air inlet 5 into the housing interior space 3. After the passage of the air to be cleaned from the raw side into the pure side through a filter medium (not shown in figure 1 ) which is provided on the filter element, the cleaned air can flow out of the housing interior space 3 again via an air outlet 6 which is provided on the end side on the filter housing 2. The air outlet 6 can be attached in a housing bottom 7 of the filter housing, which housing bottom 7 delimits the housing interior space 3 along an axial direction A of the cylindrical filter housing 2. The axial direction A extends parallel to a longitudinal center axis M of the filter housing 2. A radial direction lies perpendicularly with respect to the axial direction A. A circumferential direction rotates about the longitudinal center axis M of the filter housing 2. The housing bottom 7 and the circumferential wall 4 of the filter housing can be configured in two pieces and can be fastened releasably to one another by means of a clip or latching connection.

Figure 2 shows the filter housing 2 without the housing bottom 7 and without a filter element which is arranged in the housing interior space 3, in a perspective illustration. As figure 2 clearly illustrates, a flow guiding device 8 which has a plurality of flow guiding elements 9 can be arranged in the housing interior space 3. The flow guiding elements 9 serve to optimize the airflow in the housing interior space 3. The flow guiding device 8 is fastened releasably to an inner side 10 of the circumferential wall 4 of the filter housing 2. Figure 3 shows a first design variant of the flow guiding device 8 in a separate, perspective illustration. Accordingly, the flow guiding device 8 comprises a main body 1 1 , on which the flow guiding elements 9 are formed. As can be seen from figure 3, the main body 1 1 has the geometry of a cylinder segment. In the example of figure 3, the main body 1 1 with the geometry of a cylinder segment extends in a cross section perpendicularly with respect to the axial direction A along a circumferential direction U of the filter housing 2 or the main body 1 1 over an angle of approximately 90°. A main body 1 1 of this type is also familiar to a person skilled in the art as a "quarter circle body". In alternative variants of the example which are not shown in the figures, said angle can also have values of 180° or approximately 360°. Said two variants are familiar to a person skilled in the art under the terms "semicircle body" and "full circle body".

In the example of figure 3, the flow guiding device 8 comprises a main body 1 1 , on which the flow guiding elements 9 are arranged. In the example of figure 3, the flow guiding elements 9 are configured on the main body 1 1 in a grid-like manner with at least a plurality of grid columns 12 and a plurality of grid lines 13. This results in a grid-like structure 14. A plurality of radially outwardly projecting fastening struts 15 are formed on the main body 1 1 for fastening the flow guiding device 8 to the inner side 10 of the circumferential wall 4 of the filter housing 2. For clarification, reference is made to figure 5 which shows the filter housing in a cross section perpendicularly with respect to the axial direction A. In accordance with figures 3 and 5, two mounting rails 16 are attached on the fastening struts 15, which mounting rails 16 can be introduced into receiving elements 17 which are present on the inner side 10 of the filter housing 2 and are of complementary configuration with respect to the mounting rails 16. The mounting rails 16 and the fastening struts 15 are preferably formed integrally on one another and also integrally on the main body 1 1 of the flow guiding device 8. The receiving elements 17 are likewise configured in the manner of rails 18 and will be called receiving rails 18 in the following text, which receiving rails 18 extend along the axial direction A of the filter housing 2 on the inner side 10 of the circumferential wall 4. The receiving rails 18 project inward from the inner side 10 of the circumferential wall 4, into the housing interior space 3.

In the example of figure 3, two receiving elements 17 in the form of receiving rails 18 are present on the filter housing 2, with the result that each receiving rail 18 is assigned precisely one mounting rail 16. In order to mount the flow guiding device 9 on the filter housing 2, first of all the housing bottom 7 is removed from the circumferential wall 4 of the filter housing 2. Subsequently, the mounting rails 16 of the flow guiding device 8 are pushed along the axial direction A into the receiving rails 18 which are present on the circumferential wall 4 of the filter housing 2, and are fixed in the housing interior space 3 by means of a latching or clip connection (not shown). By means of the fastening struts 15 which project radially outward from the main body 1 1 , the main body 1 1 of the flow guiding device 8 can be held on the circumferential wall 4 at a spacing from the latter after being pushed into the housing interior space 3.

If the illustration of figure 2 is now considered again, it can be seen that the air inlet 5 has an aperture 19 which is configured on the circumferential wall 4 of the filter housing 2 and through which the raw air to be filtered can flow in from the outside into the housing interior space 3. As figure 2 clearly illustrates, the main body 1 1 of the flow guiding device 8 is arranged in the region of the aperture 19 on the inner side 10 of the circumferential wall 4, with the result that it covers said aperture 19 at least partially in an opaque manner with regard to a viewing direction along a radial direction of the filter housing 2.

Figure 4 shows one variant of the flow guiding device 8 from figure 3. The flow guiding device 8 from figure 4 differs from that from figure 3 in that the flow guid- ing elements 9 are configured as flow guiding fins 20 which project radially outward from the main body 1 1 . In the example of figure 4, two flow guiding fins 20 of this type are provided by way of example, but a different number of flow guiding fins 20 is also possible in variants. The flow guiding fins 20 are of curved configuration in a longitudinal section (not shown in the figures) of the filter housing 2 along the axial direction A. In further variants of the example, the flow guiding elements 9 can also have a different geometry and can be arranged in a different arrangement on the main body 1 1 . In particular, a spiral-like arrangement (indicated in figure 6) is conceivable of flow guiding elements 9 which project radially outward from the main body 1 1 and are arranged between the main body 1 1 and the circumferential wall 4 of the filter housing 2.

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Claims

1 . A filter device (1 ), in particular an air filter, for a fresh air system of an internal combustion engine,

- having a filter housing (2) which delimits a housing interior space (3),

- having a filter element which is arranged in the housing interior space (3) and divides the housing interior space (3) into a raw side and a pure side,

- having a flow guiding device (8) comprising flow guiding elements (9),

- wherein the flow guiding device (8) is configured such that it can be fastened to an inner side (10) of the filter housing (2) and can be removed from the housing interior space (3) at least after first assembly.

2. The filter device as claimed in claim 1 ,

characterized in that

at least one receiving element (17), preferably a plurality of receiving elements (17), is/are configured on the inner side (10) of the filter housing (2), to which receiving element/elements (17) the flow guiding device (8) is fastened or can be fastened releasably.

3. The filter device as claimed in claim 2,

characterized in that

the at least one receiving element (17) is configured as a receiving rail (18) which extends along an axial direction (A) of the filter housing (2) and into which the flow guiding device (8) can be pushed axially.

4. The filter device as claimed in claim 3,

characterized in that

the receiving rail (18) is provided on a circumferential wall (4) of the filter housing (2) and projects inward from said circumferential wall (4), into the housing interior space (3).

5. The filter device as claimed in one of the preceding claims,

characterized in that

an air inlet (5) for introducing raw air to be cleaned into the housing interior space (3) is configured in the filter housing (2),

the flow guiding device (8) being arranged in the region of the air inlet (5) on the inner side (10) of the filter housing (2).

6. The filter device as claimed in claim 5,

characterized in that

the air inlet has an aperture (19) which is configured in the filter housing and is covered at least partially in an opaque manner with regard to a viewing direction in a radial direction of the filter housing (2) by the flow guiding device (8) which is fastened to the filter housing (2).

7. The filter device as claimed in one of the preceding claims,

characterized in that

the flow guiding device (8) comprises a main body (1 1 ), on which the flow guiding elements (9) are arranged.

8. The filter device as claimed in one of the preceding claims,

characterized in that

the flow guiding elements (9) are arranged on the main body (1 1 ) in a grid-like manner with at least two grid columns (12) and at least two grid lines (13).

9. The filter device as claimed in claim 8,

characterized in that

the main body (1 1 ) has the geometry of a cylinder segment.

10. The filter device as claimed in claim 8 or 9,

characterized in that

the main body (1 1 ) with the geometry of a cylinder segment extends in a cross section perpendicularly with respect to the axial direction (A) along a circumferential direction (U) over an angle of approximately 90° or approximately 180° or approximately 360°.

1 1 The filter device as claimed in one of claims 8 to 10,

characterized in that

the main body (1 1 ) is arranged at a spacing from the circumferential wall (4) of the filter housing (2).

12. The filter device as claimed in one of claims 8 to 1 1 ,

characterized in that

the flow guiding elements (9) are configured as flow guiding fins (20) which project radially outward from the main body (1 1 ).

13. The filter device as claimed in one of claims 8 to 12,

characterized in that

the flow guiding elements (9) are arranged in a spiral manner between the main body (1 1 ) of the flow guiding device (8) and the circumferential wall (4) of the filter housing (2).

14. The filter device as claimed in one of claims 8 to 13, characterized in that

the main body (1 1 ) has a plurality of fastening struts (15) which project radially outward and on which at least one mounting rail (16) is attached which can be pushed into the at least one receiving slide (18) which is present on the inner side (10) of the filter housing and is of complementary configuration with respect to the mounting rail (16).

15. The filter device as claimed in one of the preceding claims,

characterized in that

the flow guiding device (8) comprises at least two mounting rails (16) which are arranged at a spacing from one another.

16. The filter device as claimed in one of the preceding claims,

characterized in that

the flow guiding device (8) is fastened or can be fastened releasably to the filter housing (2) by means of a clip or latching connection.

17. An internal combustion engine,

- having a fresh air system for introducing fresh air into the combustion chambers of the internal combustion engine,

- having a filter device (1 ) as claimed in one of the preceding claims which is present in the fresh air system.