Water separation element, filter element and filter device

Abstract

Water separation element, in particular for a liquid filter, with a sieve fabric (2) for water separation, which is constructed from fabric threads (7, 8) arranged at an angle to one another, and with at least one annular support part (3, 4) to which the edge region of the sieve fabric (2) is firmly connected, wherein the sieve fabric (2) is cylindrical and can be flowed through in the radial direction and the annular support part (3, 4) is arranged on an end face of the sieve fabric (2), wherein the fabric threads (7, 8) of the sieve fabric (2) are at an angle of greater than 0° and less than 90° to the facing side edge (3a, 4a) of the support part (3, 4), at least in sections, characterized in that the fabric threads (7, 8) of the sieve fabric (2) run parallel or orthogonal to the longitudinal axis (5) of the water separation element (1).

Description

Technical field

[0001] The invention relates to a water separation element with a sieve fabric for water separation, as well as to a filter element and a filter device with such a water separation element. State of the art

[0002] DE 20 2006 011 264 U1 discloses a filter element for oil and emulsion separators, which can be used to separate oil and emulsion droplets in a gaseous fluid. The filter element comprises a screen mesh designed as a flat fabric strip enclosed by lateral frame parts. The medium to be cleaned flows against the screen mesh parallel to the lateral frame parts, with both the upstream and downstream sides of the screen mesh being arranged at an angle other than 90° to the flow direction of the medium to be cleaned. Due to the angular arrangement, contaminants can deposit on the lower part of the screen mesh.

[0003] From WO 2014 / 057 323 A1, a filter cartridge for filtering fuel is known, comprising an annular filter element and a water separating element, as well as a drain channel for separated water and a cannula arranged outside the filter medium. Disclosure of the invention

[0004] The invention is based on the object of designing a water separation element, which is provided with a sieve fabric for water separation, in a stable manner using simple structural measures.

[0005] This object is achieved according to the invention with the features of claim 1. The subclaims specify expedient further developments.

[0006] The water separation element according to the invention can be used in a liquid filter, for example in an oil or fuel filter, wherein the mesh of the water separation element is used to separate water, for example the water components in the fuel. The mesh of the water separation element is cylindrical and the fluid to be cleaned flows through it in the radial direction. The water separation element with the mesh is used as one of several filtration stages in a filter element of a filter device, in particular as a final separator on the clean side of the filter element. However, the water separation element with the mesh can also be used as the sole filtration stage in a filter device.

[0007] The screen fabric, on which the water separation takes place and which is preferably made of a hydrophobic material, is constructed from straight fabric threads that are arranged at an angle to one another. This results in the net-like structure of the screen fabric. In particular, there are first fabric threads that run parallel to one another, and second fabric threads that also run parallel to one another, with the first and second fabric threads being arranged at an angle to one another. The angle between the first and second fabric threads is preferably 90°, although a different angle is also possible. The fabric threads are, for example, warp threads and weft threads.

[0008] In the area of at least one end face, the cylindrical screen fabric is arranged on an annular support member. The first and / or second fabric threads of the screen fabric are at an angle to the facing side edge of the annular support member, with the angle being greater than 0° and less than 90°.

[0009] This angular arrangement between the fabric threads of the screen mesh and the side edge of the support part to which the screen mesh is connected has the advantage that the screen mesh is exposed to lower forces and is less prone to tearing compared to prior art designs with orthogonal or parallel alignment of the fabric threads to the side edge. Particularly in the area where the fabric threads are connected to the annular support part, shear forces arise when the flow through the screen mesh due to the radial pressure applied to the support geometry that supports the screen mesh at the end faces and possibly on longitudinal struts, which can lead to tears in the screen mesh. With the angular alignment according to the invention between the side edge at which the connection to the screen mesh is made, relative to the first and / or second fabric threads of the screen mesh, the shear forces are reduced, thus also reducing the risk of the screen mesh tearing.

[0010] If the first and second fabric threads from which the screen mesh is constructed are at a 90° angle to each other, both the first and second fabric threads form an angle greater than 0° and less than 90° with the facing side edge of the support part. In designs in which the fabric threads form an angle other than 90° to each other, it is sufficient for either only the first or only the second fabric threads of the screen mesh to form an angle greater than 0° and less than 90° with the facing side edge of the support part. However, even in this case, there are constellations in which the first and second fabric threads each form an angle greater than 0° and less than 90° with the adjacent side edge of the support part.

[0011] The connection between the screen mesh and the support member is preferably achieved by embedding the screen mesh into the support member using an injection molding process. It may be advantageous for both the screen mesh and the support member to be made of plastic components.

[0012] The fabric threads are connected at least over a section of the circumference to the facing side edge of the support part, with which they form an angle greater than 0° and less than 90°. It may be sufficient to provide such an angular position between the fabric threads and the adjacent side edge of the support part only over a circumferential angle between 180° and less than 360°; if necessary, a circumferential angle less than 180°, but greater than 0°, in particular greater than 45°, preferably greater than 90°, is sufficient. According to an advantageous embodiment, it is provided that over the entire circumferential angle of 360°, the fabric threads of the screen fabric are at an angle greater than 0° and less than 90° to the facing side edge of the support part, thereby ensuring that increased strength is guaranteed in every direction of flow onto the screen fabric.

[0013] According to a further advantageous embodiment, the angle between the mesh threads and the side edge of the support part lies in an angular range between 45° and 75°. Within this angular range, the shear forces in the area where the mesh is connected to the annular support part are minimal.

[0014] According to the invention, the first fabric threads run parallel to the longitudinal axis of the water separation element, while the second fabric threads extend, in the case of a 90° angle to the first fabric threads, in the circumferential direction of the cylindrical screen fabric. The angular alignment between the first fabric threads extending in the axial longitudinal direction and the facing side edge of the support part is achieved by a corresponding, geometric design of the side edge of the support part. The side edge runs at an angle to the circumferential direction, at least in sections. This also results in the first fabric threads of the screen fabric extending in the axial longitudinal direction extending at an angle other than 90°.

[0015] According to a further advantageous embodiment, the side edge of the support part facing the screen mesh is composed of several straight sections, each of which runs at an angle other than 90° to the longitudinal axis of the water separation element. In particular, in the embodiment in which the side edge of the support part forms an angle with the fabric threads of the screen mesh over its entire circumference, it is expedient for the side edge facing the screen mesh to be composed of several assembled straight sections over its entire circumference, with two adjacent straight sections being at an angle to one another. In this way, when the annular support part is unrolled, a zigzag-shaped side edge with individual straight sections is obtained. The straight sections are advantageously of equal length, and the angle between two adjacent sections can also be the same.

[0016] According to a further advantageous embodiment, the cylindrical screen mesh is enclosed at its two axially opposite end faces by an annular support member. The side edge of each support member facing the screen mesh forms an angle greater than 0° and less than 90° with the mesh threads, at least in some sections. Accordingly, the screen mesh is connected at an angle to the respective support member at its two axially opposite end faces, thus reducing the risk of damage due to shear forces at both end faces.

[0017] According to an advantageous embodiment, the two annular support parts are mirror-symmetrical to each other, at least with respect to the side edge adjacent to the screen mesh. This has the advantage that identical or at least similar support parts can be used for both end faces of the screen mesh.

[0018] According to a further advantageous embodiment, the two annular support parts on the opposite end faces of the screen mesh are designed such that the free axial length of the screen mesh available for separation is at least approximately the same at every point around the circumference. This design has the advantage that a constant area of the screen mesh is available for separation around the circumference. In the event that the two annular support parts are mirror-symmetrical to one another, they are arranged offset from one another in the circumferential direction in order to ensure the same axial length at every circumferential point.

[0019] According to yet another expedient embodiment, longitudinal struts are incorporated into the support part, in particular into the cylindrical screen fabric, which extend from end to end and are in particular each connected to the support parts. The longitudinal struts improve the stability of the screen fabric. Several longitudinal struts can be incorporated distributed over the circumference, for example six or eight longitudinal struts. The screen fabric extends in the circumferential direction between each two adjacent longitudinal struts and in the axial direction between the support parts. The longitudinal struts are advantageously made of a plastic material. Furthermore, it is expedient for the longitudinal struts and the first or second fabric threads of the screen fabric to run parallel to one another, for example parallel to the longitudinal axis of the water separation element.

[0020] It may be advantageous for the longitudinal struts to be integrated into the screen mesh, particularly in such a way that the longitudinal struts are partially or completely located radially within a cylindrical envelope of the screen mesh. This design has the advantage that the longitudinal struts do not protrude radially outward beyond the screen mesh, or at least only a small portion (main portion radially inward), and a smooth-walled outer surface is formed.

[0021] The filter device, which serves to accommodate the water separation element, has a filter housing, which may contain additional filtration stages for filtering the fluid. For example, it may be expedient to use a multi-stage filter element in the filter device, which has one or more filter medium bodies for particle filtration and a water separation element for water separation, which preferably represents the last filtration stage in the filter element. Short description of the drawings

[0022] Further advantages and practical embodiments can be found in the further claims, the description of the figures, and the drawings. They show: Fig. 1 in perspective view a water separation element for a liquid filter, with a cylindrical sieve fabric for water separation, which is enclosed at its opposite end faces by a support part, Fig. 2 in an enlarged view the screen mesh in the transition to a support part, Fig. 3 the side edge of the support part facing the screen fabric in a state developed into a plane, Fig. 4 in a perspective, partially sectioned view of a filter element having various filtration stages, the last filtration stage being a water separation element with a sieve fabric for water separation.

[0023] In the figures, identical components are provided with the same reference symbols. Embodiment(s) of the invention

[0024] In Fig. Figure 1 shows a water separation element for a liquid filter that can be used for water separation, for example, for separating water droplets from fuel. The water separation element 1 has a cylindrically shaped screen mesh 2, each of which is firmly connected at its two end faces to an annular support part 3, 4. The screen mesh 2 and the support parts 3, 4 are advantageously made of plastic.

[0025] Longitudinal struts 6 are incorporated into the screen mesh 2, running parallel to the longitudinal axis 5 of the water separation element 1. Several longitudinal struts, for example eight longitudinal struts, are evenly distributed around the circumference. The longitudinal struts 6 and the screen mesh 2 are advantageously firmly connected to one another, with the screen mesh being located between two adjacent longitudinal struts.

[0026] How Fig. 1 in conjunction with Fig. 2, the annular support parts 3, 4, which are firmly connected to the screen mesh 2 and the longitudinal struts 6, are each provided on their side facing the screen mesh with a side edge 3a or 4a, which runs at an angle of greater than 0° and less than 90° with respect to the longitudinal axis 5 of the water separation element 1. The screen mesh 2 has first and second fabric threads 7, 8, which form a net-like fabric in the manner of weft and warp, with the first fabric threads 7 running parallel to the longitudinal axis 5 of the water separation element and the second fabric threads 8 running in the circumferential direction. In the area where the screen mesh 2 is connected to the support parts 3 and 4, both fabric threads 7 and 8 thus form an angle with the respective side edge 3a or 4a of the support part that is greater than 0° and less than 90°.This ensures that when the fluid to be cleaned flows radially through the screen mesh 2, in particular radially from the outside to the inside, shear forces in the area of the connection between the screen mesh 2 and the support parts 3 and 4 are reduced, so that the risk of a tear in the screen mesh 2 is also reduced.

[0027] The two axially opposite support parts 3 and 4 are arranged mirror-symmetrically to each other, at least with respect to their respective side edges 3a, 4a, but offset in the circumferential direction. This results in a free axial length of the screen mesh that is at least approximately equal at all points along the circumference.

[0028] In Fig. 3 shows the side edge 3a, 4a of the support part 3 or 4 in the developed, flat state. The side edge 3a, 4a is composed of individual straight sections, each of which adjoins one another and forms an angle to one another. Relative to the longitudinal axis 5 of the water separation element - and thus also relative to the first fabric threads 7 of the screen fabric 2 - each straight section of the side edge 3a, 4a runs at an angle of approximately 60°. The angle between two directly adjacent sections of the side edge 3a, 4a is approximately 120°. Distributed over the entire circumference of 360°, a total of four straight sections of equal length are provided, so that each section extends over an angular segment of 90°.

[0029] In Fig. 4 shows a filter element 20 comprising several filtration stages, with the water separation element with the cylindrical screen fabric 2 representing the inner, final filtration stage. The filter element 20, through which the fluid flows radially from the outside to the inside, has a filter medium body 10 located radially on the outside, which is axially enclosed by end plates 11, 12 and designed as a pleated filter. On the radially inner side, the filter medium body 12 has a support structure 13 that provides stability to the filter medium body 10 and supports it. Between the support structure 13 and the filter medium body 10 is a coalescer element 14, at which an agglomeration of finely distributed water droplets, which are dispersively distributed in the fluid passing through, takes place, whereby the water droplets accumulate to form larger droplets.

[0030] The filter medium body 10 forms the first filtration stage, the coalescer element 14 the second filtration stage. The screen mesh 2, which forms the third filtration stage, is arranged within the support frame 13. The screen mesh 2 is, as in the first embodiment according to Fig. 1 to 3, in the region of its two axially opposite end faces, each is enclosed by an annular support part 3 or 4, the side edges 3a or 4a of which extend at an angle relative to the longitudinal axis of the filter element 20. The fabric threads from which the sieve fabric 2 is constructed are also at an angle other than 90° to the side edges 3a and 4a.

Claims

[1] Water separation element, in particular for a liquid filter, with a sieve fabric (2) for water separation, which is constructed from fabric threads (7, 8) arranged at an angle to one another, and with at least one annular support part (3, 4) to which the edge region of the sieve fabric (2) is firmly connected, wherein the sieve fabric (2) is cylindrical and can be flowed through in the radial direction and the annular support part (3, 4) is arranged on an end face of the sieve fabric (2), wherein the fabric threads (7, 8) of the sieve fabric (2) are at an angle of greater than 0° and less than 90° to the facing side edge (3a, 4a) of the support part (3, 4), at least in sections, characterized by that the fabric threads (7, 8) of the sieve fabric (2) run parallel or orthogonal to the longitudinal axis (5) of the water separation element (1). [2] Water separating element according to claim 1, characterized bythat the side edge (3a, 4a) of the annular support part (3, 4) is at an angle of between 45° and 75° with respect to the longitudinal direction of the fabric threads (7, 8). [3] Water separating element according to claim 1 or 2, characterized by that over the entire circumference the longitudinal direction of the fabric threads (7, 8) is at an angle to the facing side edge (3a, 4a) of the carrier part (3, 4). [4] Water separating element according to one of claims 1 to 3, characterized by that the side edge (3a, 4a) of the support part (3, 4) facing the sieve fabric (2) is composed of straight sections which run at an angle to the longitudinal axis (5) of the water separation element (1). [5] Water separating element according to one of claims 1 to 4, characterized bythat the cylindrical screen fabric (2) is enclosed at each of its two end faces by an annular support part (3, 4) and the fabric threads (7, 8) of the screen fabric (2) are at least partially at an angle of greater than 0° and less than 90° to the respectively facing side edge (3a, 4a) of the support part (3, 4). [6] Water separating element according to claim 5, characterized by that the two annular support parts (3, 4) are mirror-symmetrical to one another. [7] Water separating element according to claim 5 or 6, characterized by that the two annular support parts (3, 4) are designed in such a way that the free axial length of the sieve fabric (2) available for separation is at least approximately the same at every point over the circumference. [8] Water separating element according to claims 6 and 7, characterized bythat the two annular support parts (3, 4) are arranged offset from one another in the circumferential direction in such a way that the free axial length of the sieve fabric (2) available for separation is at least approximately the same at every point over the circumference. [9] Water separating element according to one of claims 1 to 8, characterized by that longitudinal struts (6) are inserted into the cylindrical screen mesh (2). [10] Water separating element according to claim 9, characterized by that the longitudinal struts (6) run parallel to the longitudinal axis (5) of the water separation element (1). [11] Water separating element according to claim 9 or 10, characterized by that the longitudinal struts (6) are integrated into the screen mesh (2) and lie radially within a cylindrical envelope of the screen mesh (2). [12] Filter element with a filter medium body (10) and with a water separation element (1) according to one of claims 1 to 11. [13] Filter device with a filter element according to claim 12 or a water separating element (1) according to one of claims 1 to 11 and with a filter housing for receiving the filter element or water separating element (1).

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