Sealing element, method for manufacturing a sealing element, and use of a sealing element manufactured by such a method - Patents.com

Abstract

The present invention relates to a method for manufacturing a sealing element (10) having a substantially rectangular basic shape with a first direction of elongation (12) and a second direction of elongation (14) and a number of openings (18, 20). The manufacturing method according to the invention is technically simpler and more cost-effective compared to the manufacturing methods known from the prior art, since the sealing element (10) is formed in an unrolled mold by an injection or compression molding process and then a substantially cylindrical final profile is formed. The present invention also relates to the sealing element (10) produced by such a method and its use.

Description

[Technical field]

[0001] The present invention relates to a sealing element having a substantially rectangular basic shape with a first and a second direction of elongation and a plurality of openings, to a method for manufacturing such a sealing element, and to the use of a sealing element manufactured by such a method. [Background technology]

[0002] Such sealing elements are known, for example, from EP 3385583 A1 or WO 2021 / 087106.

[0003] In many "old" technology sectors, such as the established automotive industry in Germany, the focus is no longer solely on developing new products. Instead, the focus is on improving existing technology to increase efficiency and reduce costs. This applies at all levels, from engines to washers. In addition to the above demands, the increase in functionality also presents challenges with regard to solving problems in increasingly small installation spaces.

[0004] One example of the above problem is the thermal management module of a motor vehicle. Today, partly due to the ever-increasing electrification of the drive train, a large number of coolant flows, which may have different temperature levels, need to be controlled. For this reason, rotary slide valves with several internal channels and several connections are increasingly used. They are very compact and, thanks to their various positions, can simultaneously realize and control various coolant flows as required. Such rotary slide valves require special seals that seal between a housing in which the various connections are provided and the rotary slide valve arranged inside the housing in such a way that only the intended flow through the valve body is allowed.

[0005] The aforementioned EP 3385583 A1 was identified as the closest prior art. EP 3385583 A1 describes such a multiport valve consisting of a housing including an inner cavity and several connections, a rotatable cylindrical valve body with an internal channel arranged inside the cavity of the housing, and a sealing element. The sealing element has an essentially sleeve-like shape and has several openings. The sealing element is arranged to surround the cylindrical valve body within the cavity of the housing.

[0006] WO 2021 / 087106, also mentioned first, has a sealing element similar to EP 3385583 A1, which differs from the latter in that it does not have a complete sleeve shape, but rather the sleeve shape is interrupted over its entire axial length in certain sections.

[0007] Chinese utility model CN212564523U describes a liquid distributor, which is composed of a housing, a rotating shaft, and a flange connector. The flange connector can select different liquids by rotating the rotating shaft. The parts can be manufactured by plastic injection molding, resulting in a simple structure and low manufacturing cost. US Patent Application No. 2010 / 319796A1 relates to a multi-port valve including a valve housing, a directional component, and an elastomeric seal. The directional component inside the housing rotates to create channels that connect various combinations of openings depending on the orientation. The elastomeric seal between the directional component and the housing ensures a fluid-tight seal and low friction. The sealing elements of the first two documents mentioned above have in common that their basic shape corresponds at least partially to that of a hollow cylinder or sleeve, even when not installed. The sophisticated three-dimensional shape places high demands on the production of the sealing elements. Such injection molding processes require complex injection molding tools including several slides or at least one downstream punching or cutting process. This results in high production costs for the manufacturer, which in turn means a high price for the individual parts for the consumer. Summary of the Invention [Problem to be solved by the invention]

[0008] It is therefore the object of the present invention to describe a sealing element and a manufacturing method therefor which is technically simpler and therefore less expensive to manufacture than is the case for sealing elements known from the prior art. The use of a sealing element manufactured according to such a method is a further aspect of the present invention. [Means for solving the problem]

[0009] This problem is solved by a sealing element which in the unrolled state comprises a basic shape which is essentially rectangular and has a first and a second direction of elongation as well as a number of openings and a substantially cylindrical final contour, characterized in that the sealing element is manufactured from at least two materials, the second material completely or partially covering the first material in a third direction of elongation, the third direction of elongation being arranged at right angles to the first and second directions of elongation. Further advantageous embodiments are the subject of further dependent method claims 2 to 16.

[0010] Further aspects are solved by a method for producing such a sealing element according to claim 17 and by the use thereof according to claim 22. Further advantageous embodiments of the production method are the subject matter of the dependent claims 18 to 21 and further advantageous embodiments of the use are the subject matter of the dependent claims 23 to 25.

[0011] In its most general form, the present invention provides for the first time a manufacturing process for sealing elements in which the initial shaping is performed in a non-rolled mold by injection or compression molding before the substantially cylindrical final contour is formed. Compared to the prior art, such a process represents a cost-effective and easy-to-control option for manufacturing substantially cylindrical sealing elements that can be used in such a way. Complex three-dimensional geometries of vulcanization tools, additional slides, or further process steps for post-treatment and / or further processing can be dispensed with.

[0012] For the primary molding, the elastomeric material is heated and molded under pressure in a vulcanization tool. The correct combination of temperature, pressure and other parameters is important to obtain the viscosity of the elastomeric material required for vulcanization. In addition to the described embodiments with elastomeric materials, embodiments are also conceivable in which at least two elastomeric materials are used. These elastomeric materials may be homogeneously mixed or may be heterogeneously arranged. The latter offers the possibility, for example, to realize a core made of one elastomeric material and a covering made of a second elastomeric material.

[0013] The cavity of the vulcanization tool corresponds to the unrolled shape of the sealing element to be produced. In the case of a first embodiment of the production method according to the invention, the cavity has a substantially rectangular basic shape with a first direction of elongation and a second direction of elongation arranged at right angles to the first direction of elongation. The first direction of elongation and the second direction of elongation thus span a substantially rectangular frame surrounding a plurality of openings. The openings are separated from one another by webs, which are connected to the frame and which are also formed during the injection or compression molding process.

[0014] If the aim is to obtain a sealing element with properties that cannot be obtained with the elastomeric material alone, it is also possible to insert an additional component, such as a film, into the vulcanization tool and to chemically or mechanically bond the sealing element to the additional component, so that bonding with the additional component already occurs when the sealing element is formed.

[0015] Following the injection or compression molding process, the resulting sealing element is rolled into a substantially cylindrical final profile. The first elongation direction corresponds to the circumferential direction of the cylindrical final profile, while the second elongation direction is coaxial with the imaginary central axis. As a result, elastic deformation by bending occurs in the first elongation direction, but not in the second elongation direction.

[0016] According to an advantageous embodiment, it is proposed to give the individual segments of the sealing element a partially cylindrical shape during the injection or compression molding process in order to relieve the prestress introduced by the elastic deformation. For this purpose, the vulcanization tool is designed in such a way that all sections of the frame aligned along the first elongation direction and any webs extending in the same direction have a correspondingly curved geometry. The point in the first elongation direction of the frame where the webs extending in the second elongation direction meet the frame is excluded from this. In very abstract terms, the cavity of the vulcanization tool, and therefore also the sealing element produced therewith after the injection or compression molding process, can be said to have a wave-like shape. The point where the webs extending in the second elongation direction meet the frame represents the head of the wave, while the center of the preformed segment represents the bottom of the wave.

[0017] In a further embodiment of the present invention, one or more starting materials of elastomers and / or polymers are used as materials.In particular, variants are conceivable in which some sections of the sealing element are made of elastomers and other sections are made of polymers.Both elastomers and polymers have a good ratio of flexibility and friction resistance in their final form and are frequently used as sealing materials.

[0018] In one advantageous embodiment, the sealing element is tempered after the moulding vulcanisation process, which strengthens the bonds between the molecules and improves the elastic properties of the sealing element.

[0019] In another advantageous embodiment, the sealing element is partially or completely coated. In this case, for example, a PTFE coating on all sections that form the dynamic sealing surface during the subsequent operation is conceivable. Such a coating can be used to reduce the friction resistance of the corresponding sliding pair without adversely affecting the sealing properties.

[0020] According to one or more claims for the use described in more detail below, the sealing element according to the invention serves to seal a cylindrical rotary slide valve of a media distributor with respect to its housing. Such a media distributor is used in particular in applications in which several fluid flows, essentially independent of one another, must be regulated simultaneously. The various fluid flows may differ, inter alia, with respect to their temperature, pressure and volumetric flow rate. In particular the latter may require connections of various sizes in the housing and channels in the cylindrical rotary valve. Thus, further embodiments of the sealing element according to the invention are conceivable, in which the individual openings or some of the openings have different sizes. Naturally, variants are also conceivable in which some openings have the same size and individual other openings or some other openings have different sizes.

[0021] Based on the above different size possibilities, embodiments are also conceivable in which the openings of the sealing element have different shapes. Depending on their suitability for the particular application, the openings can have, for example, rectangular, circular or elliptical shapes, although other geometric shapes are of course also conceivable. In particular, this also includes asymmetric shapes. A single sealing element can also have openings of different shapes.

[0022] In addition to size and shape, the arrangement of the multiple openings also depends on the application. One or more of the openings may be arranged next to each other in both the first and second directions. Symmetry of the repeating pattern or arrangement is possible, although asymmetric arrangements are also contemplated.

[0023] The frame and the webs of the sealing element may have an essentially rectangular cross-sectional profile. It is also possible for the cross-sectional profile to have a circular, triangular, curved or other shape. The choice is made in each case according to the individual requirements.

[0024] In one use of the sealing element according to the invention, the invention provides a stationary seal for the housing of the media distributor and a dynamic seal for the cylindrical rotary slide valve. To ensure that the sealing element cannot rotate relative to the housing of the media distributor during operation, in one embodiment the sealing element has one or more grooves on the radially outer side of its substantially cylindrical final contour. One or more corresponding springs provided on the radially inner side of the housing of the media distributor engage in this or these grooves.

[0025] It is also possible to reverse the tongue-and-groove connection described above. Thus, according to a further embodiment, one or more springs are provided on the radially outer side of the substantially cylindrical final contour of the sealing element. These springs engage in one or more corresponding grooves arranged on the radially inner side of the housing of the media distributor. The springs formed during the sulphurization process are an inherent part of the sealing element.

[0026] In particular, according to the above-mentioned embodiment teaching a tongue-and-groove connection between the sealing element and the surrounding housing of the media distributor, the sealing element can also perform the function of a bearing shell for the cylindrical rotary valve. Thus, if the stiffness of the sealing element is high enough, radial forces can be absorbed via the sealing element. This offers the possibility to save one or more bearings of the shaft driving the cylindrical rotary slide, which may bring advantages in terms of installation space and costs. Furthermore, overdetermination and axial misalignment between the cylindrical rotary slide valve and the housing of the media distributor can be better compensated via a dynamic sealing surface between the sealing element and the cylindrical rotary slide valve.

[0027] According to an alternative embodiment, the sealing element can be rotationally fixed relative to the cylindrical rotary valve, so that the sealing element forms a static sealing surface as a result. In this case, a dynamic sealing surface exists between the sealing element and the housing of the media distributor, which radially surrounds the sealing element. To ensure this relationship, the sealing element can have one or more grooves on the radially inner side of its cylindrical contour. One or more corresponding springs provided on the radially outer side of the cylindrical rotary slide of the media distributor engage in this or these grooves.

[0028] It is also possible to reverse the tongue-and-groove connection described above. Thus, according to a further embodiment, one or more springs are provided on the radially inner side of the substantially cylindrical final contour of the sealing element. These springs engage in one or more corresponding grooves arranged on the radially outer side of the cylindrical rotating slide.

[0029] In the following the invention will be explained in more detail with reference to the drawings. [Brief description of the drawings]

[0030] [Figure 1] 1A and 1B are a top view and a side view, respectively, of a first embodiment of a sealing element according to the present invention, respectively, of the sealing element according to the present invention shown in FIG. [Diagram 2](a) Various cross-sectional profiles of a section of a sealing element according to the present invention. (b) Various cross-sectional profiles of a section of a sealing element according to the present invention. (c) Various cross-sectional profiles of a section of a sealing element according to the present invention. (d) Various cross-sectional profiles of a section of a sealing element according to the present invention. (e) Various cross-sectional profiles of a section of a sealing element according to the present invention. (f) Various cross-sectional profiles of a section of a sealing element according to the present invention. (g) Various cross-sectional profiles of a section of a sealing element according to the present invention. [Diagram 3] 3a and 3b are a top view and a side view, respectively, of a second embodiment of a sealing element according to the present invention, respectively, of the sealing element according to the present invention shown in FIG. [Figure 4] FIG. 3c is a view of the sealing element shown in FIGS. 3a and 3b in its substantially cylindrical final contour in an installed state. [Diagram 5] 5a and 5b are a top view and a side view, respectively, of a third embodiment of a sealing element according to the invention, respectively. [Figure 6] FIG. 5b shows the sealing element according to FIGS. 5a and 5b in its substantially cylindrical final contour in the installed state. [Figure 7] FIG. 4 shows a fourth embodiment of a sealing element according to the invention in an installed state. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0031] 1a to 7 show various embodiments and states of a sealing element according to the invention. The process required to manufacture such a sealing element is explained with reference to these figures, without the individual process steps being represented by separate drawings.

[0032] FIG. 1a shows a top view of a first embodiment of a sealing element 10 according to the invention. As can be seen from FIG. 1a in conjunction with FIG. 1b, which shows a side view of the same sealing element 10, the sealing element 10 is a substantially flat and planar structure. The sealing element 10 comprises a first extension direction 12 along which a frame 16 of the sealing element 10 is passed and a second extension direction 14 which is essentially arranged perpendicular to the first extension direction 12, the frame 16 having an essentially rectangular shape. In addition, the sealing element 10 comprises several openings, some of which are provided in FIG. 1a by way of example with the reference symbols 18 and 20. The openings 18, 20 are each separated from one another by a web 22 which connects to a further web 22 or to the frame 16.

[0033] 1a and 1b show the sealing element 10 before the final step of the manufacturing process according to the invention. To obtain such a sealing element, the sealing element 10 is first shaped in an injection or compression molding process. The cavity of the associated vulcanization tool thus has the exact shape of the sealing element 10 to be produced, but in an unrolled form. In a final process step, the sealing element 10 shaped in its unrolled form is rolled by guiding towards each other two sections of a frame 16 positioned in a second stretch direction 14. This creates an approximately cylindrical final profile in which the original first stretch direction 12 runs along the periphery, while the original second stretch direction 14 is arranged coaxially with an imaginary central axis of the cylindrical final profile. FIG. 4, discussed in detail below, shows the sealing element 10 thus rolled in its approximately cylindrical final profile in the installed state.

[0034] 2a to 2g show possible shapes of the cross-sectional profile of the frame 16 and / or the webs 22. As shown in FIG. 2a, such a cross-sectional profile can have a rectangular shape, with the inner and outer corners and edges having lesser or more pronounced rounding depending on the individual application. According to FIG. 2c, it can also be coated on one or more sides, preferably on the sides that form the dynamic sealing surface during operation. A PTFE coating is an option in this case, for example. It is also possible that the sealing element 10 is composed of two materials that are bonded to each other during the vulcanization process. Round cross-sectional shapes are also conceivable (FIG. 2b), as are triangular cross-sectional shapes (FIGS. 2d to 2f), which can be oriented differently. In addition, cross- or X-shaped cross-sectional shapes are also conceivable (FIG. 2g), as are other shapes not shown in FIGS. 2a to 2g. All sections of the frame 16 and webs 22 of the sealing element 10 preferably have the same cross-sectional shape. However, embodiments are also conceivable in which the individual sections of the frame 16 and / or the individual or some webs 22 have different cross-sectional shapes. The appropriate selection is made for each individual case based on the particular operating conditions.

[0035] 3a and 3b show a further embodiment of the sealing element 10 according to the invention. The top view shown in FIG. 3a corresponds exactly to the top view in FIG. 1a. As can be seen from the corresponding side view in FIG. 3b, the individual sections of the sealing element 10 positioned in the first extension direction 12 are preformed partially cylindrical. On the one hand, this concerns the sections of the frame 16 positioned in the first extension direction 12, but may also include the webs 22 also positioned in the first extension direction 12. The radius of these partial shells 24 approximately corresponds to the radius of the sealing element 10 in its approximately cylindrical final contour. Like the sealing element 10 of FIGS. 1a and 1b, the sealing element 10 of FIGS. 3a and 3b can be manufactured using a relatively simple vulcanization tool. To manufacture a sealing element 10 with such a shape, complex slides can be omitted during the injection molding process, just as complex post-processing, punching or cutting, etc. can be omitted.

[0036] One advantage of such an embodiment of the sealing element 10 preformed with a partial shell 24 is that less bending stress is exerted on some parts of the sealing element 10 when forming the final, substantially cylindrical contour. This supports a more reliable performance of the sealing function of the sealing element 10. It also reduces friction and the resulting section modulus, which may be taken into account when designing the actuator.

[0037] According to an advantageous embodiment, the sealing element 10 according to the invention is designed such that in its substantially cylindrical final contour the circumference of the sealing element 10 comprises one or more grooves 26. These are already provided during the initial shaping by the corresponding design of the vulcanization tool. In the installed state shown in FIG. 4, these grooves form a secure connection together with corresponding springs of the housing of the media distributor which surround the sealing element 10 on its radial outside. This connection prevents rotation and therefore ensures the correct positioning of the sealing element 10 in the housing.

[0038] Figures 5a and 5b show a further embodiment of the sealing element 10 according to the invention, in which the tongue-and-groove connection is reversed compared to the embodiment example of figures 3a and 3b. One or more springs 28 therefore project in a radially outward direction from the substantially cylindrical final contour of the sealing element 10. This shape is also already provided during the design of the vulcanization tool for the initial shaping.

[0039] As shown in Fig. 6, these one or more springs 28 correspond, in the installed state, to one or more corresponding grooves in the media distributor housing. Similar to the previous example, such a design prevents the sealing element 10 from rotating relative to the media distributor housing.

[0040] In contrast, Figure 7 shows an embodiment of the sealing element 10 which makes do with a single spring 28. The desired anti-rotation lock is created by interaction with a corresponding spring in the housing. The corresponding selection of the appropriate number of tongue-and-groove connections and their alignment is made for each individual case based on the individual operating conditions.

[0041] The latter embodiment example, in which the spring 28 is designed as part of the sealing element 10, allows for less local loss of cross-sectional profile height. The overall stability and rigidity of the sealing element 10 can therefore be improved. Since the groove is provided in the housing of the media distributor in this design example, the diameter of the housing increases in order to maintain a minimum wall thickness. From this it can already be seen that the design of the tongue-and-groove connection must be selected for the individual application and on the basis of the operating conditions. [Explanation of symbols]

[0042] 10 Sealing element 12 First extension direction 14 Second extension direction 16 Frames 18 Openings 20 Opening 22 Web 24 Partial Shell 26 Groove 28 Spring

Claims

1. A method for manufacturing a sealing element (10) having a substantially rectangular basic shape with a first direction of elongation (12) and a second direction of elongation (14) and a plurality of openings (18, 20), comprising: the sealing element (10) is formed in a non-rolled mold by an injection molding process or a compression molding process; and Then, the final contour of the approximately cylindrical shape is formed. A method comprising:

2. After forming the substantially cylindrical final contour, the first extension direction (12) extends along the periphery of the substantially cylindrical final contour, and the second extension direction (14) extends parallel to an imaginary central axis of the substantially cylindrical final contour. The method according to claim 1 , characterized in that

3. At least one section of the sealing element (10) is given a partially cylindrical shape during the injection molding process or the compression molding process. The method according to claim 1 or 2, characterized in that

4. the at least one section of the sealing element (10) that is given a partially cylindrical shape in the injection molding process or the compression molding process is aligned along the first elongation direction (12); The method according to claim 3, characterized in that

5. The sealing element (10) is made of an elastomeric material.

5. The method according to claim 1, wherein the first and second electrodes are connected to each other.

6. The sealing element (10) is manufactured from at least two materials, at least one of which is an elastomeric material, and the at least two materials are distributed uniformly or non-uniformly during the injection molding process or the compression molding process.

5. The method according to claim 1, wherein the first and second electrodes are connected to each other.

7. The sealing element (10) is annealed in the unrolled form or in the final generally cylindrical configuration after the initial forming.

7. The method according to claim 1, wherein the first and second electrodes are arranged in a first direction.

8. The sealing element (10) is partially or completely covered before the final substantially cylindrical contour is formed.

8. The method according to claim 1 , wherein the first and second electrodes are arranged in a first direction.

9. The sealing element (10) is chemically or mechanically bonded to additional components during the injection molding process or the compression molding process.

9. The method according to claim 1, wherein the first and second electrodes are arranged in a first direction.

10. 10. Produced by the process of any one of claims 1 to 9. A sealing element (10) having a plurality of openings (18, 20).

11. The plurality of openings (18, 20) may have uniform and / or different sizes. The sealing element (10) according to claim 10, characterized in that

12. The plurality of openings (18, 20) have a symmetrical and / or asymmetrical shape. The sealing element (10) according to claim 10 or 11, characterized in that

13. the plurality of openings (18, 20) being arranged one behind the other and / or next to each other in the first direction of extension (12); The sealing element (10) according to any one of claims 10 to 12, characterized in that

14. The cross-sectional profile of a section of the sealing element (10) has a circular shape, an angular shape, or another shape. The sealing element (10) according to any one of claims 10 to 13, characterized in that

15. having one or more grooves (26) on its radially outer side in its generally cylindrical final profile to form an anti-rotation lock; The sealing element (10) according to any one of claims 10 to 14, characterized in that

16. having one or more springs (28) on its radially outer side at its generally cylindrical final profile to provide an anti-rotation lock; The sealing element (10) according to any one of claims 10 to 14, characterized in that

17. having one or more grooves (26) on its radially inner side in its generally cylindrical final profile to form an anti-rotation lock; The sealing element (10) according to any one of claims 10 to 14, characterized in that

18. having one or more springs (28) on its radially inner side at its generally cylindrical final profile to provide an anti-rotation lock; The sealing element (10) according to any one of claims 10 to 14, characterized in that

19. A sealing element (10) made of two materials, the second material completely or partially covering the first material in a third direction of extension, said third direction of extension being disposed at right angles to said first direction of extension (12) and to said second direction of extension (14). The sealing element (10) according to any one of claims 10 to 18, characterized in that

20. the area between at least two sections of the sealing element (10) that are given a partially cylindrical shape in the injection or compression molding process is designed as a predetermined buckling point; The sealing element (10) according to any one of claims 10 to 19, characterized in that

21. the predetermined buckling point having a reduced wall thickness; The sealing element (10) according to claim 20, characterized in that

22. The predetermined buckling point of a sealing element (10) made of at least two types of materials is made of only one type of material.

22. The sealing element (10) according to claim 20 or 21, characterized in that

23. Use of a sealing element (10) comprising a plurality of openings (18, 20) according to any one of claims 10 to 22, manufactured by the method according to any one of claims 1 to 9, for sealing a cylindrical rotary slide valve of a media distributor against a housing of said media distributor.

24. the sealing element (10) being rotationally fixed relative to the housing and forming a dynamic sealing surface together with the cylindrical rotating slide; Use of a sealing element (10) according to claim 23, characterized in that

25. The sealing element (10) is rotationally fixed relative to the cylindrical rotary valve and forms a dynamic sealing surface together with the housing. Use of a sealing element (10) according to claim 23, characterized in that

26. The sealing element (10) also serves the function of a bearing shell for the cylindrical rotating slide.

26. Use of a sealing element (10) according to claim 25, characterized in that

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