DE102018002908A1 - Filter element and filter device - Google Patents

Abstract

The invention relates to a filter element (1), in particular for a liquid filter, in particular for a water or urea filter, in particular for a filter of a water injection system of an internal combustion engine. The filter element (1) comprises an at least partially fluid-permeable inner support body (11) which is preferably bent in at least one bend portion about a longitudinal axis (L) and has a predetermined extent in the longitudinal direction, wherein the inner support body (11) is adapted to a filter medium ( 12), which at least partially covers the inner support body (11) on an inner and / or outer circumferential surface of the inner support body (11) and there at least partially fluid-flow, to keep spaced. Furthermore, the filter element (1) has a discharge connection (113), which has a fluidic connection to an inner space spanned by the inner support body (11). According to the invention, the inner support body (11) can be flowed through fluidically on at least one end face, wherein the at least one end face is covered at least in sections with the filter medium (12). Furthermore, a filter device is disclosed which has a filter element (1) according to the invention.

Description

Technical area

The present invention relates to a filter element and a filter device with such a filter element, in particular for a liquid filter, in particular for a water or urea filter, in particular for a filter of a water injection system of an internal combustion engine.

Filter elements are used to separate impurities contained in a fluid from the fluid. Typical filter elements are designed as cylindrical filter elements and generally have an elongated, grid-shaped support element. On the support element, a filter medium is supported, which can be flowed through by the fluid in a direction radial to the longitudinal axis of the filter element.

Such filter elements are used, for example, in the filtering of fuels or of water and aqueous solutions, for example urea solutions, which are used for the reduction of nitrogen oxides in the exhaust gas of internal combustion engines of motor vehicles. In addition, water injection systems for internal combustion engines in the field of motor vehicles are becoming more and more widespread, since fuel injection quantities used only for cooling in the full load range can be avoided by substituting them with water for cooling the components of the internal combustion engine into the combustion chamber Combustion chamber is introduced. Water injection systems have a need for clean water and therefore require a filter.

In practice, however, the installation space available for the filter element, in particular in motor vehicles, is often severely limited and, not least because of other components, has a complex geometry. Furthermore, the above-mentioned urea and / or water filters are often designed as Intank filter and are, for example, fluidly connected to a built-in tank pump, suitably in the suction mode. From such a construction situation, further space restrictions are derived.

State of the art

Out DE 10 2015 003 101 A1 For example, a urea filter is known which has a curved or kidney-shaped shape in order to allow a good adaptation to a complex installation space. The filter has an inner support body on which there is an outflow nozzle, which is fluidically connected to an inner space spanned by the inner support body. The inner support body is bent about a longitudinal axis and has a pronounced extension along the longitudinal axis. At its end faces in each case a fluid-tight end disk is present. About the inner support body, a filter medium is drawn, which is completely circumferential and fluid-tightly connected to the upper and lower end plate. A disadvantage of this filter is that the filter element provides flowability only on its inner and outer lateral surface.

Proceeding from this, it is therefore an object of the invention to provide a filter element, with the optimal space utilization, especially for curved or kidney-shaped space, an increased filter surface can be accommodated.

This object is achieved by a filter element having the features of independent claim 1 and by a filter device having the features of claim 15.

Embodiments of the invention

The filter element according to the invention is designed in particular for a liquid filter, in particular for a water or urea filter, in particular for a filter of a water injection system of an internal combustion engine. Of course, the filter element is also suitable for filtering gaseous media streams. It comprises an at least partially fluid-permeable inner support body which has a predetermined extent in the longitudinal direction. The inner support body is designed to hold a filter medium, which covers the inner support body at least on a lateral surface at least partially spaced. The inner support body is in this case at least partially overflowed on the at least one lateral surface. Furthermore, the filter element has an outflow nozzle, which has a fluidic connection to an inner space spanned by the inner support body. The inner support body is also fluid-flowable on at least one end face, wherein the at least one end face is also covered with the filter medium. The inner support body thus spans a covering surface covered with a filter medium, in the center of which there is an inner space which, in the case of a sucking system arrangement of the filter element in a filter device, corresponds to the clean space. Suitably, the areas covered by the filter medium of the end and / or lateral surfaces are those areas in which there is a fluid permeability, for example through openings, openings or the like.

Suitably, the inner support body on at least two lateral surfaces, for example, an inner and outer circumferential surface, which are covered with the filter medium, fluid-flowable. If due to the structure of the inner support body no Inside / outside is clearly defined, the attributes inside / outside can be replaced by first / second. The fluid flowability of the inner support body can in principle be achieved by any measures, for example by providing a plurality of flow openings, which are distributed over an envelope surface of the inner support body. In a sucking flow through the filter element, ie a suction through the outflow and inflow into the interior through the surrounding filter medium, the clean room is located in the region of the interior. The separation of a surrounding raw side thereof is done by the surrounding the inner support body filter medium. In principle, however, the filter element can also be flowed through in reverse, with the outflow nozzle assuming the function of an inflow nozzle.

Particle filter media, for example cellulose-based or fully synthetic, water and / or oil-separating media, in particular screen cloth or coalescer, can be understood as the filter medium. Furthermore, the filter medium may have at least one gas-adsorbing active layer.

As already mentioned, the filter element is also suitable in principle for gas filters, wherein the available flow cross sections of the inner support body and the outflow neck must be adapted individually to the respective media characteristics.

Characterized in that the inner support body on at least one end face (in addition to at least one of the lateral surfaces) can be flowed through and is covered in this area with the filter medium, a significantly enlarged filter area is achieved in comparison to the prior art with the same construction volume. On the one hand, this can be used to achieve an increased filter service life with identical construction volumes; on the other hand, a smaller construction volume can be implemented with identical filter performance. As a result, the strict installation space requirements, in particular in the motor vehicle sector, can be fulfilled even better by the filter element according to the invention.

The filter element or its inner support body, which defines the shape, preferably has an open cross section, but embodiments are possible which have a closed cross section.

The outflow can have both a male and a female fluid connection element, which are designed, for example, radially sealing. Furthermore, nozzles are possible, which are axially sealed. Alternatively or additionally, this may have a circular cross-section.

According to a particularly preferred embodiment it is provided that the inner support body is bent in at least one bending portion about a longitudinal axis, in particular is formed in a circular arc; However, this does not preclude further bent portions around the same or another axis, and possibly also with a reversed direction of curvature, or there are also unbent portions. In particular, the at least one lateral surface of the inner support body, which is at least partially fluid-flowable and at least partially covered with the filter medium, in this case an inner and / or outer lateral surface.

In a preferred embodiment, the inner support body is at least partially fluid-flowable at both end faces, and the two end faces are at least partially covered with the filter medium, whereby a further optimized total filter surface is obtained.

According to yet another embodiment, it is provided that the inner support body is formed cuff-shaped. Under cuff shape is understood a curved shape with an open cross-section, which extends partially circumferentially on at least one radius. The circumferential extension angle can be between 30 and 340 °, preferably between 60 and 300 °.

Further, the filter medium may be integrally formed and pulled loose over the inner support body. This has the advantage that expensive welding steps, such as with both end plates, as required in the prior art, can be omitted.

Furthermore, the filter medium may be present as a tube material, which is particularly advantageous, as described above. can be pulled over the inner support body. The tube material can also be produced from a web or flat material during production; For this purpose, the flat material with its edges connected to each other, for example, welded, glued, sewn. Furthermore, it is possible to provide the filter medium in the production of the filter element as a prefabricated sock-shaped precursor, which further reduces the assembly effort.

According to a very particularly preferred embodiment, the tube material is pulled over the inner support body in such a way that it projects beyond the inner support body at its free ends or edges and is connected to one another at the free ends or edges, for example welded. Since the filter medium only needs to be welded to itself, the production of the filter element is much easier and cheaper possible. A welding tool, In order to weld the (flat) filter media layers together, it is also much simpler since it does not reflect complex geometries.

The welding of the free ends of the tubing together may be present at opposite circumferential ends or longitudinal ends of the inner support body, but the welding is preferred at the circumferential ends, since the simplest possible weld geometry can be found here.

According to a further embodiment it can be provided that the outflow nozzle is integrally formed on the inner support body, preferably formed integrally with the inner support body. As a result, a relative position of the discharge nozzle with respect to the inner support body is optimally determined; a reliable installation of force from the inner support body to the outflow allows easy installation of the filter element in a filter element receptacle of a filter system with coupling of Abströmstutzens present in the filter element receiving corresponding inflow. The coupling of the Abströmstutzens the filter element with the inflow of the filter device can also serve for mechanical attachment of the filter element. Alternatively or additionally, however, separate holding elements may also be present on the filter element, for example fastening pins, snap hooks and the like.

The outflow nozzle can extend away from the inner support body in the radial direction, preferably radially inward, or in the longitudinal direction.

The filter medium may be directly or indirectly fluid-tightly connected to the outflow nozzle, preferably welded, more preferably ultrasonically welded.

According to a particularly preferred embodiment, the outflow nozzle may have a gore-shaped connecting region which preferably has a gradual transition from a curvature of the outflow nozzle to a curvature of the inner support body, wherein the filter medium is connected to the outflow nozzle in the connection region. In this way, in particular, a welding of the filter medium to the outflow nozzle can be carried out with a lower outlay on equipment. In particular, it is thereby sufficient to use a welding device with only one welding direction, whereas at least two welding directions are to be used in the case of a round / circular cross section.

The outflow can, as already mentioned, either present in the bending portion of the inner support body or in a straight, unbent portion. The radius transition through the gore-shaped connection region can therefore be effected on a bend of the bending section or correspondingly on the unbent section. A gore-shaped section is here understood to mean a smooth transition from a comparatively small radius of the outflow nozzle to a comparatively large radius of the inner support body, which tapers to a terminal end. The gore-shaped connection region can have a curvature reversal.

In a further embodiment, it can be provided that the inner support body has a plurality of support ribs, of which there is at least one inner support rib on an inner radius and an outer support rib on a different outer radius thereof. The support ribs preferably run at least partially in the longitudinal direction. The support ribs are adapted to support the filter medium and to prevent it from collapsing due to a negative pressure difference induced by the outflow nozzle, thereby reducing the effective filter area. The filter medium is preferably not connected to the support ribs, but is only loosely attached thereto.

Alternatively or additionally, the inner support body may have at least one at least partially curved sheet web, which is preferably connected to the support ribs. The at least one arch web may in particular be formed integrally with the support ribs. According to a particularly preferred embodiment variant, the inner support body may have at least two longitudinally spaced arch webs, which are connected by the support ribs. The sheet or web (s) support the filter medium with respect to the height direction, but do not limit the flow through in this area, since the filter medium is preferably not connected to the sheet webs, but only loosely applied thereto.

Finally, the at least one arch web of the inner support body can have at least one through-flow opening, which is preferably designed as a particular annular flow-through gap. The throughflow opening of the at least one sheet web in this case provides at least one fluid throughflow capability on an end face of the inner support body.

Another aspect of the invention relates to a filter device, in particular water or urea filter device, in particular a filter of a water injection system of an internal combustion engine. This comprises at least one housing whose outer contour is bent at least in sections around a longitudinal axis in the region of a filter element receptacle, wherein a filter element according to the invention is accommodated in the filter element receptacle and there is an inlet connection which is fluidically connected to a discharge connection of the filter element. In particular, a pump can be arranged in the housing of the filter device. Alternatively or additionally, the filter device can be designed as a fully integrated Intank filter device.

The presently mentioned in relation to the filter element technical effects and their advantages are each applicable to the filter device and vice versa. Features and feature combinations disclosed in connection with the filter element therefore also apply to the filter device as disclosed and vice versa.

The bleed-off bleed port described herein is an independent invention that is not subject to the limitations of the inventive filter element and is applicable to other types of filters. In addition, such a trained connection area is not only suitable for outflow, but also for inflow, basically for any nozzle types. Advantageously, such a nozzle with a gusset-shaped connecting region is suitable for all filtration applications in which two filter media layers are provided with a connection in a fluid-tight manner, for example any bag or bag filter.

Such a discharge nozzle for a filter element, in particular for a liquid filter, in particular for a water or urea filter, in particular for a filter of a water injection system of an internal combustion engine, for example, has a hollow cylindrical fluid connection region from which at least one side a zwikelförmig tapered connection region extends radially away, the allows a gradual transition from a curvature of the hollow cylindrical fluid port region to a substantially non-curved end portion of the connecting region. In the connection region, an envelope of the cross section may in particular have a sign change of the curvature. At least one flat filter medium layer can be connected to the connection region, in particular can be welded. The connection region itself may have a predetermined longitudinal extension, which may also be shorter than a longitudinal extent of the hollow cylindrical fluid connection region. In each case, on both sides of the hollow-cylindrical fluid connection region, in each case a gore-shaped connection region, which is preferably mirror-symmetrical, extends. A bag or bag filter having such a discharge nozzle, can be obtained from flat media layers with few manufacturing steps: providing two media layers, one above the other, inserting the zwipelförmig tapered connecting portion of the Abströmstutzens between the media layers in an edge region of the filter media layers, circumferentially welding the filter media layers in the edge region, while also welding the filter media layers with the gore-shaped converging connection region of the outflow in only one welding direction. As a result, a bag-shaped structure is obtained in which the outflow pipe separates a clean from a raw side. Advantageously, the bag filter can be operated in the suction mode, wherein a suction through the filter medium bag and an outflow through the nozzle, for example, for use as Intank filter.

• 1 eine isometrische Ansicht eines erfindungsgemäßen gebogenen Filterelements mit transparentem Filtermedium;
• 2 eine Draufsicht des erfindungsgemäßen Filterelements, wobei der zwickelförmig zulaufende Verbindungsbereich des Abströmstutzens erkennbar ist,
• 3 eine isometrische Ansicht eines erfindungsgemäßen gebogenen Filterelements;
• 4 eine isometrische Ansicht eines erfindungsgemäßen nicht gebogenen Filterelements;
• 5 eine isometrische Ansicht eines Innenstützkörpers des Filterelements aus 4.

The invention is explained below with reference to exemplary embodiments shown in the drawing. In the drawings shows:

• 1 an isometric view of a curved filter element according to the invention with transparent filter medium;
• 2 a top view of the filter element according to the invention, wherein the gore-shaped converging connection region of the Abströmstutzens is recognizable,
• 3 an isometric view of a bent filter element according to the invention;
• 4 an isometric view of a non-curved filter element according to the invention;
• 5 an isometric view of an inner support body of the filter element 4 ,

In 1 is the filter element according to the invention 1 shown in an isometric view. The filter element 1 is particularly suitable as a filter element 1 for a liquid filter, in particular for a water or urea filter, in particular for a filter of a water injection system of an internal combustion engine. This can be received in a corresponding receptacle of a housing of a filter device, wherein the housing may preferably be formed as an Intank unit. The filter element 1 is preferably operated in the suction mode, wherein through the outflow 113 By a pump liquid from the surrounding tank volume is sucked, which through the filter medium 12 in one through the inner support body 11 clamped interior of the filter element 1 was sucked. The filter medium 12 is shown transparently, so that the therein inner support body 11 can be viewed.

The inner support body 11 of the filter element 1 is bent in a bend portion about the longitudinal axis L and has a substantially cuff-like shape, ie it has an open cross-section with a predetermined wrap angle. The inner support body 11 defines the shape of the filter element 1 while the filter medium 12 is slippery and adapts to this shape. About the inner support body 11 is the filter medium 12 pulled loose, which is present as a hose material and at its free ends 121 welded together to form a closed filter media bag. The filter medium 12 is also with the outflow 113 connected fluid-tight, in particular welded, so that the above-formed filter media bag exclusively on the outflow 113 can be flowed through fluidically.

The inner support body has in the embodiment shown a plurality of support ribs 112a . 112b on, extending in the longitudinal direction L. Furthermore, the inner support body has bow struts 111 . 111 . 111b , each longitudinally axially spaced and over the longitudinal struts 112a . 112b are connected. The lower arch strut in the view shown 111 . 111b consists of two partial arch struts 111 . 111b which are offset coaxially in the radial direction and in between an annular flow-through gap 114 form. The upper strut in the picture 111 is in relation to the lower arch strut 111 . 111b between the radius of the inner partial arc strut 111b and the outer partial arch strut 111 arranged. The longitudinally extending support ribs 112a . 112b are each in the circumferential direction alternately on the inner partial arc strut 11b and on the outer partial arch strut 111 arranged so that the filter medium 12 is supported adequately from both radially inward and radially outward. Regarding the upper bow strut 111 are the longitudinally extending support ribs 112a . 112b respectively in the circumferential direction alternately on the outer and inner surfaces of the upper arc strut 111 arranged, in particular connected to this.

The terms used herein above and below are to be understood as exemplary only and have been chosen based on a concrete Verbausituation. In other embodiments, of course, the other of the bow struts 111 . 111 . 111b the two partial arch struts 111 . 111b with the annular flow gap 114 or both arc struts 111 . 111 . 111b are structured in this way. Instead of "upper" and "lower" could the bow struts 111 . 111 . 111b Also referred to as first and second bow strut.

The inner support body 11 is with its device components, the longitudinal struts 112a . 112b , Arch struts 111 . 111 . 111b and outflow 113 , integrally formed and in particular made of plastic. This can be made particularly simple and inexpensive as an injection molded part.

In the manufacture of the filter element 1 is advantageously of a prefabricated inner support body 11 went out and then present as tubing filter medium 12 put over it, so this at its free ends 121 a supernatant against the inner support body 11 having. The filter medium 12 is then at its free ends 121 welded together and also in the Abströmstutzens 113 with the discharge nozzle itself respectively the inner support body 11 welded. Advantageously, the present as a hose material filter medium 12 be prepared already pre-assembled and already welded, for example, at one circumferential end, so that it is virtually a sock-shaped precursor. The thus pre-assembled filter medium can also be on the outflow 113 Having tuned opening through which after the slipping of the tubular filter medium precursor of the outflow 113 can be guided through. The opening may be in the form of a simple incision or, for example, a punch-out.

One for the direct welding of the filter medium 12 with the outlet connection 113 particularly advantageous contour of the same is in 2 , in particular in detail A, shown.

The outlet connection 113 has all sides (top / bottom, left / right) a gore-shaped connecting area 113 ' . 113 ' on, with which the filter media layers 12 are welded. Due to the thus gradual Radienübergangs between the circular outflow 113 with a comparatively small radius and the surrounding comparatively large radius of the inner support body 11 can the welding of the filter media layers 12 take place in only one welding direction V. There are only two welding jaws / sonotrodes for the welding process 2 sufficient. The connection area 113 ' . 113 ' of the outlet nozzle 113 in this case points between the circular cross section of the outflow neck 113 itself and the terminal gore-shaped inlet a sign change in the curvature.

In 3 is finally the curved filter element according to the invention 1 shown in another isometric view, wherein the filter medium 12 not shown transparently. The filter medium 12 is available as tubing and is at its longitudinal ends 121 welded; the weld is visible. Furthermore, it can be seen that the tubular filter medium 12 starting from a flat material was obtained, which along the seam 122 , in particular weld 122 , was connected. Alternatively, the connection can be made in the area of the seam 122 abutting media layers also done by gluing or sewing. Advantageously, by a (heat) welding, especially in synthetic filter media, a stiffening, which contributes to an increased overall rigidity of the filter element.

In 4 is an alternative filter element according to the invention 1 which differs from the one described above only in that it is not bent.

5 shows the inner support body. Construction and production are otherwise identical. Thus, when referring to the first curved embodiment of the filter element, curved device components are mentioned, these descriptions are readily applicable to the unbent variant, provided that the curvature is zero. Descriptions of device components that are identified with the attributes inside / outside (for example, inner and / or outer lateral surface) may instead be provided with the attributes first / second (for example, first and / or second lateral surface).

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 102015003101 A1 [0005]

Claims (16)

Filter element (1), in particular for a liquid filter, in particular for a water or urea filter, in particular for a filter of a water injection system of an internal combustion engine, comprising an at least partially fluid-permeable inner support body (11) having a predetermined extent in the longitudinal direction (L), wherein the Inner support body (11) is adapted to a filter medium (12), the at least partially covering the inner support body (11) on at least one lateral surface of the inner support body (11) to keep spaced, wherein the inner support body (11) on the at least one lateral surface at least partially fluid can be flowed through, and wherein the filter element (1) has a discharge nozzle (113) which has a fluidic connection to an inner space spanned by the inner support body (11), characterized in that the inner support body (11) further at least partially on at least one end face fluid can be flowed through, wherein the at least one end face is at least partially covered with filter medium (12). Filter element after Claim 1 characterized in that the inner support body (11) is bent in at least one bending portion about a longitudinal axis (L), in particular circular arc-shaped, wherein preferably at least one lateral surface of the inner support body (11), which is at least partially fluid-flowable and at least partially with the Filter medium (12) is covered, an inner and / or outer circumferential surface. Filter element after Claim 1 or 2 , characterized in that the inner support body (11) at both end faces at least partially fluid-flowable and the two end faces are at least partially covered with filter medium (12). Filter element according to one of Claims 1 to 3 , characterized in that the inner support body (11) is formed cuff-shaped. Filter element according to one of Claims 1 to 4 , characterized in that the filter medium (13) is in one piece and is pulled over the inner support body (11). Filter element after Claim 5 , characterized in that the filter medium (12) is present as a tube material. Filter element according to one of the preceding claims, characterized in that the present in particular as a hose material filter medium (12) is pulled over the inner support body (11) that it projects beyond the inner support body (11) at its free ends (121) and to the free Ends (121) is connected together, preferably welded. Filter element after Claim 7 , characterized in that the welding of the free ends (121) of the present in particular as a hose material filter medium (12) on opposite circumferential ends and / or longitudinal ends of the inner support body (11) is present. Filter element according to one of the preceding claims, characterized in that the outflow nozzle (113) is integrally formed on the inner support body (11), preferably integrally formed with the inner support body (11). Filter element according to one of the preceding claims, characterized in that the outflow nozzle (113) extends in the radial direction, preferably radially inward, or in the longitudinal direction (L) of the inner support body (11) away. Filter element according to one of the preceding claims, characterized in that the filter medium (12) with the outflow nozzle (113) is directly or indirectly fluid-tightly connected, preferably welded, more preferably ultrasonically welded. Filter element according to one of the preceding claims, characterized in that the outflow neck (113) has a gland-shaped connecting region (113 ', 113 ") which preferably has a gradual transition from a curvature of the outflow neck (113) to a curvature of the inner support body (11). wherein the filter medium in the connecting region (113 ', 113 ") is connected to the outflow nozzle (113). Filter element according to one of the preceding claims, characterized in that the inner support body (11) has a plurality of support ribs (112a, 112b), of which at least one inner support rib (112a) on an inner radius and an outer support rib (112b) on one of them outer radius is present. Filter element according to one of the preceding claims, characterized in that the inner support body (11) at least one at least partially curved sheet web (111, 111a, 111b), which is preferably connected to the support ribs (112a, 112b), preferably integrally with the support ribs ( 112a, 112b), more preferably the inner support body (11) has at least two longitudinally spaced arcuate webs (111, 111a, 111b) respectively connected by the support ribs (112a, 112b). Filter element after Claim 14 , characterized in that the at least one sheet web (111, 111a, 111b) at least one flow opening, preferably a particular annular flow gap (114) which provides the Fluiddurchströmbarkeit on an end face of the inner support body (11). Filter device, in particular water or urea filter device, in particular filter of a water injection system of an internal combustion engine, comprising at least a housing, the outer contour is bent at least partially around a longitudinal axis in the region of a filter element receptacle, wherein in the filter element receiving a filter element is received and in the filter element receptacle is an inflow, which is fluidically connected to a discharge connection of the filter element, characterized in that the filter element is a filter element (1) according to one of Claims 1 to 15 is.

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