Structuring of vehicle sealing surfaces with lamellar structures

Abstract

The invention relates to a sealing element for fluid-tight sealing of a sealing partner (1) of a vehicle, wherein the sealing element has a base body (3), and wherein lamellae (5) extending transversely to a direction of a sealing effect are arranged on the base body (3), wherein spaces between the lamellae (5) have a fluid-conducting connection to the ambient pressure.

Description

[0001] The invention relates to a sealing element for fluid-tight sealing of a sealing partner of a vehicle, as well as a first and a second method for manufacturing a sealing element for fluid-tight sealing of a sealing partner.

[0002] In motor vehicles, a multitude of sealing elements are typically used to create a fluid seal between two or more components, each acting as a sealing partner. If relative movement occurs between a sealing element and a component in contact with it, such as a glass pane like the vehicle's windshield, undesirable noise can result. Smooth elastomer structures of sealing elements, in particular, can lead to high noise levels, especially if stick-slip effects occur, which can be caused by relatively high coefficients of friction.In the prior art, it is known to structure the surfaces of sealing elements, for example, by means of erosion structures of the manufacturing tool, which in particular can create stochastic structures to reduce noise generation by reducing the contact areas between a sealing element and a component.

[0003] In this context, DE 10 2011 113 246 A1 relates to a method for structuring surfaces by processing with energetic radiation, in which a first beam of energetic radiation is directed at the surface to be processed for a predetermined period of time during a processing operation, and the processing parameters relating to the first beam are selected such that the first beam creates a melt pool in the surface to be processed, wherein at least a second beam of energetic radiation is superimposed on the first beam at least in predetermined time intervals such that it at least partially strikes the surface to be processed within the extent of the melt pool, and the processing parameters relating to the at least second beam are selected such that the melt pool is deformed to structure the surface to be processed.

[0004] However, such a stochastic structuring of the sealing element has a disadvantageous effect on the sealing performance, as capillaries or very limited structural depth can reduce the sealing effect of the element compared to a smooth surface. A similar effect applies to deterministic, stand-alone structural elements based on stochastic structures. Furthermore, it is known from the prior art to design surfaces to be more easily slippery, for example, to reduce noise during sliding or slippage between surfaces.

[0005] DE 10 2015 221 041 A1 relates to a method for producing a sliding surface on a machine element, in particular a cam follower, wherein the sliding surface of the machine element is intended for sliding use in contact with at least one further machine element, wherein the at least one further machine element slides over the sliding surface in a sliding direction, wherein the machine element is first provided with a coating on at least a part of its surface, into which a surface structure is subsequently introduced by means of laser interference structuring, wherein, viewed perpendicularly to a coating surface of the coating, the surface structure is formed comprising a number of self-contained structural elements.

[0006] DE 10 2023 003 392 A1 also relates to a component which has at least a first surface area which is intended to contact a second surface area of ​​a second component, wherein the component consists of a thermoplastic elastomer mixed with a sliding additive and the first surface area has a surface structuring, wherein the surface structuring corresponds to an approximately ideal geometric surface.

[0007] EP 2616699 B1 further relates to a method for manufacturing a sliding element, comprising the following steps: producing a resin layer having a surface in which holes having a circular opening are arranged at regular intervals in a hexagonal close-packed configuration; masking a sliding surface made of a metallic material with the resin layer by bonding the surface of the produced resin layer to the sliding surface; and forming micro-depressions by bringing an etching agent into contact with the sliding surface masked by the holes;wherein the resin layer consists of a thermoplastic resin, and an area ratio of openings of all micro-depressions to the total sliding surface is set by setting an area ratio of openings of all holes to the total surface of the resin layer by stretching the resin layer by exposing the resin layer to heat before the step of forming the micro-depressions takes place.

[0008] US 8859078 B2 relates to a friction component in a lubricated medium, operating at contact pressures above 200 MPa, and having a contact surface comprising a structured layer of deposited hard material, wherein the surface has a periodic network of micrometric cavities with a maximum length between 5 and 500 µm, a period of less than half the width of the contact surface, and a depth less than the thickness of the layer, correlated with the thickness of a lubricant used to optimize the reduction of the coefficient of friction, and less than or equal to 3 µm, in the elastohydrodynamic lubrication range.

[0009] DE 10 2023 201 668 A1 relates to an axial sealing arrangement, with a first lamellar sealing area and a second lamellar sealing area, wherein the first lamellar sealing area is spaced apart from, adjacent to and surrounding the second lamellar sealing area.

[0010] DE 10 2016 220 382 A1 discloses a radial shaft sealing arrangement for wheel bearings with a sealing element that can be arranged on one of the two bearing elements rotating relative to each other. At least one axial section has a structured surface for conveying a fluid in the axial direction away from the sealing element.

[0011] DE 10 2013 222 373 B4 relates to a turbomachine with a stator and a rotor, wherein a sealing arrangement is arranged between them and connected to the stator. The sealing arrangement has a surface structure and a support structure, wherein the support structure is connected to radially oriented deformable bending plates.

[0012] DE 10 2010 039 117 A1 discloses two components movable relative to each other, on which two elements made of elastomeric material are arranged, projecting towards each other.

[0013] DE 10 2010 036 919 A1 relates to an electrically conductive seal with a sealing profile extending in a longitudinal direction and with an electrical shielding profile extending adjacent to it in the direction of its longitudinal extent. An elastic connecting profile extends between the sealing profile and the shielding profile in a direction transverse to the longitudinal extent of the sealing profile and is attached to both the sealing profile and the shielding profile.

[0014] The object of the invention is to achieve an improved reduction in the frictional resistance of a seal, in particular an elastomer seal, in order to reduce noise.

[0015] The invention is defined by the features of the independent claims. Advantageous further developments and embodiments are the subject of the dependent claims.

[0016] A first aspect of the invention relates to a sealing element for fluid-tight sealing of a sealing partner of a vehicle, wherein the sealing element has a base body, and wherein lamellae extending transversely to a direction of a sealing effect are arranged on the base body, wherein spaces between the lamellae have a fluid-conducting connection to the ambient pressure.

[0017] The sealing element serves to seal the sealing partner. This means, in particular, that a contact surface between the sealing element and the sealing partner is sealed in such a way that fluid flow between the sealing element and the sealing partner is essentially prevented. If, for example, the sealing partner is a glass pane such as a vehicle windshield, the sealing element can be used to prevent, to a significant extent, outside air from flowing into the vehicle's interior through the contact area of ​​the windshield on a mounting structure when the vehicle is moving forward. Preferably, the sealing element is used to seal a gap between a first sealing partner and a second sealing partner in a fluid-tight manner.

[0018] For this purpose, a multitude of lamellae are arranged on the base body. These lamellae can run parallel to each other, or, in an alternative embodiment, simply have a common general direction of extension. The lamellae form continuous or nearly continuous barrier structures, as overlapping barriers with narrow openings can still be fluid-tight. They create a blocking effect in the desired direction of sealing. This orientation of the lamellae results in a sealing effect in a transverse direction to the lamellae.

[0019] According to the invention, at least some of the lamellae have branches extending towards other lamellae. These branches are lower in height than the base body.

[0020] However, because the spaces between the lamellae are coupled to the ambient pressure, a suction effect cannot occur, and smacking noises are also avoided. Furthermore, the lamellae are only high enough to prevent them from becoming structurally unstable and beginning to vibrate when relative movement occurs between the base body with the lamellae and the sealing partner.

[0021] An advantageous effect of such a lamellar structure with pressure-dependent gaps between the lamellae is improved noise reduction, particularly when an elastomer is used for the sealing element. This is achieved primarily because pressure equalization allows for deeper lamellar structures, thereby increasing friction reduction and simultaneously improving the sealing function compared to stochastic structures. Further aspects include the hydrophilization or hydrophobization of materials, as well as the targeted modification of friction properties.

[0022] In particular, it is advantageously possible and preferably intended not to use any lubricant in the contact area between the sealing element and the sealing partner. It is also advantageous not to apply any coating to the lamellae.

[0023] The lamellae continue to preferably form open structural elements rather than closed ones, in order to allow pressure equalization with the ambient pressure.

[0024] The lamellae can be arranged parallel to each other or, alternatively, in more complex structures. For example, they can extend in a meandering pattern across the surface of the base body, with wave troughs and crests preferably aligned in phase across different lamellae, thus achieving a higher packing density of the lamellae on the surface of the base body. In an alternative embodiment, however, different waveforms of the lamellae can be selected to advantageously avoid the excitation of narrow spectra during relative movement between the sealing element and the sealing partner, and the resulting sliding of the lamellae across the surface of the sealing partner. Instead, different mechanical properties are achieved in the respective sections of the lamellae and distributed across the lamellae.This achieves a spreading of natural frequencies and thus reduces noise generation when relative movement occurs between the sealing partner and the sealing element. For this purpose, staggered separation between the lamellae can also be used, as well as different widths across the lamellae. Preferably, at least two lamellae have different widths.

[0025] As a further means of preventing lamella vibrations, particularly those of the same or similar frequencies, during relative movement between the sealing element and the sealing partner, branches can be provided on the lamellae to stabilize and reinforce them against movement, especially along the desired sealing action. This mechanically stabilizes the lamellae against movement along their width. The branches provide stability in the direction of the sealing action under transverse forces. In one embodiment, the branches have varying distances, lengths, and / or orientations relative to each other to spread natural frequencies and thus reduce contact noise.Branches can have a lower height than the respective lamellae in order to avoid contact between a branch and the friction partner, and thus reduce the friction surface.

[0026] Furthermore, the lamellae can exhibit stochastic or quasi-stochastic profiles, and lamellae with stochastic and deterministic or other profiles can also be combined. Additionally, bionic structures can be incorporated. Double lamellae, prismatic and / or conical geometries, especially with variable cross-sections, can also be provided.

[0027] Preferably, an arrangement of sealing element and sealing partner is given, the contact pressures of which do not exceed 50 MPa.

[0028] According to an advantageous embodiment, the lamellae are not interrupted along their length, but rather continuous and uninterrupted, in order to enable dense structures. In other words, no capillary openings are created in the lamellae.

[0029] According to an advantageous embodiment, the lamellae have a height in the range of 30 µm to 250 µm.

[0030] According to another advantageous embodiment, the ratio of width to height of each of the slats is in the range of 1 to 1 / 4.

[0031] According to another advantageous embodiment, at least some of the lamellae lie against the base body in a meandering pattern.

[0032] According to a further advantageous embodiment, the meandering lamellae are wave-shaped and at least two lamellae have different amplitudes and / or frequencies of their waves.

[0033] According to another advantageous embodiment, at least some of the lamellae are curved in sections.

[0034] Another aspect of the invention relates to a method for manufacturing a sealing element for fluid-tight sealing of a sealing partner, wherein lamellae extending transversely to a direction of a sealing effect are applied to a base body by printing onto the base body.

[0035] Another method for manufacturing a sealing element for fluid-tight sealing of a sealing partner involves applying lamellae running transversely to a direction of sealing action to a base body by embossing them onto the base body.

[0036] Other possible manufacturing processes are the following: The lamellae are produced by molding with a structured tool in a primary forming process. The lamellae are produced by laser structuring of the base body. The lamellae are produced by embossing onto an existing component. The lamellae are produced by printing the structures onto the base body.

[0037] Advantages and preferred further developments of the proposed methods result from an analogous and substantive transfer of the above statements made in connection with the proposed sealing element.

[0038] Further advantages, features and details will become apparent from the following description, in which - possibly with reference to the drawing - at least one embodiment is described in detail.

[0039] They show: Fig. 1: A sealing element with lamellae in cross-section according to an embodiment of the invention. Fig. 2: Various possible lamella arrangements on a base body according to embodiments of the invention. Fig. 3: Further various possible lamella arrangements on a base body according to exemplary embodiments of the invention. Fig. 4: Various possible lamella cross-sections according to exemplary embodiments of the invention. Fig. 5: An embodiment of a lamellar structure according to embodiment (g) of the Fig. 4 in a side view. Fig. 6: An exemplary sealing assembly with a sealing partner in cross-section.

[0040] The representations in the figures are schematic and not to scale.

[0041] Fig. Figure 1 schematically shows a side view of a base body 3, which serves as the basis for the sealing element. Several lamellae 5 are arranged on the surface of the base body 3 to achieve a seal against a fluid flow F in the direction of the arrow shown. The lamellae 1 protrude from the base body 3 to a certain height and are spaced a certain distance apart, with variations and embodiments possible, some of which are shown by way of example in the following figures.

[0042] Fig. Figure 2 shows in sub-images (A), (B), (C), (D) various possible arrangements of the lamellae 5 from a top view. For the sake of simplicity, only a single lamella 5 is designated as such in each sub-image. In sub-image (A), the lamellae are arranged with even spacing. In sub-image (B), the lamellae are arranged in a meandering pattern and exhibit geometric irregularities to form a hybrid of repeating, deterministic, and stochastic structures. In sub-image (C), the lamellae 5 have branchings 7, which are exemplified in Fig. 6 are described and detailed in more detail. Partial image (D) shows a combination of the embodiments of partial images (B) and partial image (C). Here, the lamellae 5 extend continuously, i.e., without interruption, from a first to a second end of a surface of the base body 3, while the branches extend from certain points of each of the lamellae 5 to a limited length.

[0043] Fig. Figure 3 shows alternative designs of the lamellae 5 in sub-images (E) and (F), in particular as an alternative to the designs of the Fig. 2. Examples are shown here of how different lamella configurations and arrangements can be combined with one and the same surface of the base body 3. Again, a top view of the lamellae 5 and the underlying base body 3 is shown, analogous to the Fig. 2. In sub-image (E), straight and parallel lamellae 5 are combined with chain-shaped lamellae 5 with diameter constrictions. In sub-image (F), on the other hand, lamellae 5 connected via branches are combined with meandering lamellae 5 on the surface of the base body 3.

[0044] Fig. Figure 4 schematically shows cross-sectional views of various lamellae 5 profiles in sub-figures (a) to (g). Design (a) has a triangular cross-section, which advantageously results in a small contact area between the lamella tip and the sealing partner 1. Design (b) is trapezoidal, which advantageously results in a stable lamellae structure 5 and a lesser change in the contact area due to abrasion of the lamellae 5 on their upper surface. Design (c) is an inclined lamella 5, which results in a stronger sealing effect in one direction. Design (d) is a rectangular lamella, which advantageously does not experience any change in the contact area of ​​the lamella 5 with the sealing partner 1 due to abrasion. The design of the lamella 5 in (e) is spherical or circular, which results in mechanical stability and a small contact area between the lamella 5 and the sealing partner 1.The stepped lamella 5 in sub-image (f) also enables a high degree of mechanical stability with a small contact area between the lamella 5 and the sealing partner 1, whereas, after a relative movement of the lamella 5 relative to the sealing partner 1, only a small contact area initially remains following abrasion. In sub-image (g), however, a stochastic secondary structure analogous to an EDM scar is shown, which is superimposed on the lamella 5. This advantageously further reduces the contact area between the lamella 5 and the sealing partner 1 while maintaining a sealing effect. The design of sub-image (g) is shown in more detail in [reference missing]. Fig. Figure 5 shows a side view. One of the three lamellae 5 is shown in cross-section as an example, while the second structure forms the space between the lamellae 5. Various combinations of lamellae with profiles from partial images (a) to (g) on ​​a surface of the basic structure 3 are possible and can be advantageously used to reduce noise generation.

[0045] Fig. Figure 6 shows an exemplary cross-sectional structure of a basic structure 3 with lamellae 5 on a sealing partner 1. The lamellae 5 contact the sealing partner 1 at their upper surface to create a fluid-tight seal. The lamellae 5 are laterally stabilized by branches 7, which are lower in height than the lamellae 5 themselves. This ensures that the branches 7 do not contact the sealing partner 1, thereby minimizing the contact surface of the lamellae 5 and the branches 7 with the sealing partner 1 and reducing noise generation.

[0046] Although the invention has been further illustrated and explained in detail by means of preferred embodiments, the invention is not limited by the disclosed examples, and other variations can be derived from them by a person skilled in the art without departing from the scope of protection of the invention. It is therefore clear that a multitude of possible variations exist. It is also clear that the embodiments mentioned as examples are truly only examples and are not to be understood in any way as limiting, for example, the scope of protection, the possible applications, or the configuration of the invention.Rather, the preceding description and the description of the figures enable the person skilled in the art to implement the exemplary embodiments in concrete terms, whereby the person skilled in the art, with knowledge of the disclosed inventive concept, can make various changes, for example with regard to the function or the arrangement of individual elements mentioned in an exemplary embodiment, without leaving the scope of protection defined by the claims and their legal equivalents, such as further explanations in the description.

Claims

[1] Sealing element for fluid-tight sealing of a sealing partner (1) of a vehicle, wherein the sealing element has a base body (3), and wherein uninterrupted lamellae (5) or almost uninterrupted lamellae (5) with narrow openings which are fluid-tight are arranged on the base body (3) transversely to a direction of a sealing effect, wherein spaces between the lamellae (5) have a fluid-conducting connection to the ambient pressure, characterized by , that at least some of the lamellae (5) have branches (7) towards other lamellae (5) without connecting the lamellae (5) to each other by the branches (7) and the branches (7) have a lower height from the base body (3) than the lamellae (5). [2] Sealing element according to claim 1, wherein the lamellae (5) have a height in a range of 30 µm to 250 µm. [3] Sealing element according to one of the preceding claims, wherein the ratio of width to height of each of the lamellae (5) is in the range of 1 to 1 / 4. [4] Sealing element according to one of the preceding claims, wherein at least some of the lamellae (5) are arranged in a meandering pattern on the base body (3). [5] Sealing element according to claim 4, wherein the meandering lamellae (5) are wave-shaped and at least two lamellae (5) have different amplitudes and / or frequencies of their waves. [6] Sealing element according to one of the preceding claims, wherein at least some of the lamellae (5) are curved section by section. [7] Method for producing a sealing element according to one of the preceding claims for fluid-tight sealing on a sealing partner (1), wherein lamellae (5) extending transversely to a direction of a sealing effect are applied to a base body (3) by printing onto the base body (3).

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