Connection arrangement between detachably clamped joining partners in the body structure or in the interior structure of a vehicle, as well as manufacturing process

Abstract

Connection arrangement between detachably clamped joining partners (1, 2) in the body structure or in the interior structure of a vehicle, wherein the joining partners (1, 2) are clamped against each other via their contact surfaces (1a, 2a) by means of at least one detachable fastening element, wherein hard particles (3) are applied to the contact surface (2a, 1a) of at least one of the joining partners (2, 1) prior to the manufacture of the connection arrangement and thus prior to the clamping assembly of the joining partners (1, 2) and the fastening element, which, as a result of the clamping assembly, project at least partially into the other contact surface (1a, 2a) of the other joining partner (1, 2), and wherein both joining partners are provided with a coating, characterized in that the connection arrangement is designed such that the hard particles (3) when applied to a coated joining partner (1,2) penetrate essentially completely into the coating of this joining partner (1, 2), and only exert their effect when the two joining partners (1, 2) are clamped, by penetrating the coating (15, 25) of the other joining partner (1, 2) through clamping, without penetrating the actual surface of this joining partner (1, 2), since the thickness of the coating (15, 25) is slightly reduced by clamping the two joining partners (1, 2), while the height of the hard particles (3) does not change when the joining partners (1, 2) are clamped.

Description

[0001] The invention relates to a connecting arrangement according to the preamble of claim 1. Regarding the prior art, reference is made to US 2014 / 0334868 A1 and US 2014 / 0186583 A1 as well as DE 10 2012 223 003 A1, DE 101 48 831 A1, DE 10 2009 023 402 A1 and DE 10 2008 028 688 A1.

[0002] In the area of ​​the body (in the broadest sense) of a vehicle, e.g., a passenger car, as well as in the area of ​​vehicle interior fittings, there are, as is well known, a multitude of joining partners that are detachably connected to one another. For example, a body bulkhead or a strut tower, as well as various supports or so-called shear panels and any support struts, are to be understood as a body structure or as a joining partner of the body structure, just as, for example, a hinge assembly for a door or a hatch is itself or in conjunction with a body structure part a component of the body structure, or just as a seat assembly or seat rail is itself or in conjunction with a body structure part a component of the interior fittings structure of a vehicle.

[0003] The body of a vehicle, e.g., a passenger car, also contains a multitude of sections that are connected to other components of the vehicle. Depending on the components involved, higher forces must also be transmitted via such a connection arrangement of joining partners according to the present invention. For example, this applies to any struts by which different body sections are supported against one another, or to other support struts by which, for example, one or more components of the vehicle's chassis are supported on the body or on the said body section. These struts can therefore also be a wheel-guiding control arm.This also applies to any supports by which heavier components are attached to or supported on the body – an example of this is a support for at least one element of a vehicle's drivetrain, such as a transmission support – or chassis components that are essentially combined via an axle support, on which the body or the entire vehicle structure is then partially supported (namely on a front axle and on at least one rear axle). Finally, another concrete example of a joining partner in the body structure is the so-called strut support bearing, by which a MacPherson strut or similar strut is attached to a strut tower as the aforementioned body structure.

[0004] In addition to rivets, one or more screws are usually used as detachable fastening elements in such connection arrangements, whereby a screw nut which is attached to a threaded section which is provided on one of the joining partners itself should also be considered a screw. Depending on the component in question, higher forces must be transmitted via such a connection arrangement. In particular, passenger cars have high demands on comfort, which is why it is also an important goal, for example, to have a secure connection area in the connection area of ​​the respective joining partners - for example between the contact surface of a specific joining partner in the form of a bearing element with a body section of the vehicle - in which, for example, the bearing element mentioned as an example is connected with its contact surface via one or more screws in the form of one or more of the above-mentionedFastening element(s) is braced against the body structure and thus rests against it in a braced manner, in order to avoid even the smallest relative movement. Such relative movements would generate cracking noises which would be transmitted via the body into the interior of the vehicle and can be heard by the driver. For example, a said bearing element can be a spring strut support bearing as shown in DE 101 25 822 A1. It should be noted, however, that the present invention relates to any type of separable connection arrangement in the body structure or interior fittings structure of a vehicle, since under certain circumstances when the vehicle is in operation, the said problem of cracking noises (disturbing noises) in said connection arrangement can occur at a wide variety of joining partners, resulting from micro-movements orsmallest (micro) vibrations between these components due to the forces or moments that have to be transmitted in various directions.

[0005] As already mentioned, the detachable fastening elements mentioned are usually screws which are screwed either into a suitable thread in the respective counterpart or joining partner or into a suitably arranged screw nut and which must be tightened with such a high torque that the connection between the joining partners is as rigid as a non-detachable connection, for example a welded connection. For a variety of reasons, it is important to avoid even the slightest relative movement between the joined partners. For functional reasons, in each of the application cases listed above as examples, a rigid support must be created which, in particular, does not produce any cracking noises which may arise from micro-movements or the smallest (micro) vibrations between these connected parts as a result of the forces or vibrations which have to be transmitted in a wide variety of directions when the vehicle is in operation.Moments resulting between the said joining partners or components. In addition to the noise issue, the reliable transmission of forces or moments is at least equally important for many components for reasons of rigidity and strength. Fundamentally, therefore, detachable or separable connection arrangements must be designed to be as rigid as possible, which has so far only been possible with the help of strong and large connecting screws. The connecting arrangements must also be able to withstand external shear loads to a sufficient degree. Screw connections are usually designed to be force-locked for shear loads, meaning that the resistance to shear loads depends on the screw preload and the coefficient of friction between the connecting partners. For higher shear loads, the screws must therefore be larger while maintaining the same coefficient of friction.However, this is not always easy to achieve and can require extensive changes in the connection arrangement, particularly with regard to installation space. This would also significantly increase weight and costs.

[0006] To overcome the potential problems mentioned above, it is generally known to provide hard particles between the joining partners. These hard particles dig into the joining partners when they are clamped against each other, thus acting as additional connecting elements without requiring separate installation space. This generally known technology is to be advantageously further developed with the present invention (= problem).

[0007] The solution to the problem is achieved by a connecting arrangement between separably clamped joining partners in the body structure or in the interior structure of a vehicle with the features of claim 1. Advantageous developments and further developments are the subject of the subclaims.

[0008] It is disclosed that the coefficient of friction between the contact surfaces of the joining partners, which are clamped against each other by means of at least one detachable fastening element, is increased by so-called hard particles being applied to at least one of these contact surfaces before the assembly of the connecting arrangement, which then dig in at least partially into the opposite contact surface during assembly, ie during clamping during the assembly of the joining partners and the fastening means.

[0009] To reduce or avoid even the smallest relative movements between the said components or joining partners (hereinafter, the terms "joining partner" and "component" or "component element" are used synonymously, without any distinction being intended) in the connection region according to the invention, the surface quality of at least one of these components or joining partners is specifically adapted by applying hard particles to the contact surface, for example, in such a way that the coefficient of friction between the contact surfaces is increased, namely through additional positive locking. Viewed at the micro level, when these said components or joining partners are clamped against one another, the hard particles provided according to the invention groove into the surface structure of the other component, essentially creating a micro-positive locking.

[0010] Both of the clamped components are now provided with some kind of coating. For example, at least one of the components may be painted – in vehicle construction, this is usually a cathodic dip coating. For the correct interpretation of the patent claims, such a coating is to be understood as belonging to the "contact surface." The intended hard particles are (either) only located in the coating of at least one of the components or only penetrate the coating of at least one of the components or protrude into the coating, since this alone can increase the coefficient of friction between the said components. The actual base component without its coating thus remains undamaged and cannot be damaged in any way by the hard particles.

[0011] Silicon carbide, for example, can be used as the material for the hard particles. Such hard particles (made of any suitable material) can, for example, have a size (approximately a diameter, whereby the hard particles are preferably not spherical but have a multi-edged surface with corners and points) of several (e.g. 1 - 70) micrometers. The preferably used hard particles are characterized not only by particularly high hardness (of the material of the hard particles) but preferably also by extremely sharp edges, i.e. their surface preferably has a large number of corners and edges. It is known that silicon carbide, for example, can be applied to surfaces extremely durably using plasma technology, cf. the so-called "Plasma-Grip" technology from efc plasma GmbH, Ingolstadt.These hard particles are held on the plasma-coated surface by means of a nickel adhesion promoter layer. It should be expressly noted that, by specifying this example, the present invention is by no means limited to such hard particles; rather, various other materials and methods can be used by means of which sufficiently hard particles can be applied to a contact surface of a joining partner. These hard particles at least partially penetrate into the surface or contact surface of a first joining partner when a surface or contact surface coated with such particles of a first joining partner is clamped against a second joining partner, for example one made of a (relatively softer) aluminum alloy. A positive connection is created by the hard particles being pressed at least partially into the respective other component.These hard particles also increase the total surface area over which the two components are connected to each other, which further increases the frictional force acting between these components.

[0012] A layer of hard particles applied according to the invention is naturally particularly effective when the hard particles are applied to at least one of the said surfaces or contact surfaces in a way that is at least approximately abrasion-resistant. This can be achieved, for example, by applying the hard particles using a blasting process such as pressure blasting, injector blasting or plasma blasting. This makes it possible to initially apply the hard particles to the contact surface of the first joining partner with such high pressure that they partially penetrate into it and, at the same time, partially protrude from this contact surface. If this first joining partner is then mounted on the second joining partner, the hard particles penetrate the contact surface via the fastening elements orFastening screws insert the parts of the hard particles protruding from the contact surface of the first joining partner into the possibly softer material (this also includes a surface coating) of the second joining partner.

[0013] In this context, reference is expressly made to the method claim of the present invention formulated alongside the device claims, whereby in principle, instead of a device, a method can be claimed by claiming that hard particles are applied instead of the feature that hard particles are applied

[0014] As already explained above, in a disclosed connection arrangement, at least one of the joining partners or its contact surface can have a coating, in particular a KTL coating (= cathodic dip coating). Various possibilities exist.

[0015] Thus, in an embodiment not according to the invention, the first joining partner can be coated with hard particles, while the second joining partner has a cathodic dip coating. During assembly of the connection arrangement, i.e., during the assembly of these joining partners, the hard particles of the first joining partner can only penetrate the cathodic dip coating of the second joining partner, thereby creating a micro-positive fit and, as a result, increasing the coefficient of friction between the joining partners.

[0016] Alternatively, the hard particles can be applied to the relevant surface of the first joining partner, which is already provided with a coating (such as a cathodic dip coating), before this surface is clamped to the second joining partner. In an embodiment not according to the invention, it should be ensured that the hard particles protrude at least slightly from the coating, which can, however, be specifically adjusted by suitable application of the hard particles, taking into account the hardness of the actual surface. However, even if the hard particles penetrate essentially completely into the coating, they can still exert an effect when the two joining partners are clamped, since the thickness of the coating is slightly reduced by clamping the two components (joining partners), while the height of the hard particles does not change when the joining partners are clamped.Finally, it is possible that both joining partners are coated or will be coated. In this case, the hard particles can only act on the coatings of the joining partners.

[0017] During the blasting or blasting application to one of the components explained above, the hard particles can be specifically applied or introduced onto or into the respective component by suitable control of the beam with such an impulse that these hard particles, based on their dimensions, penetrate at least approximately half into the component and protrude at least approximately half from its relevant surface (with or without any coating). Some possible blasting processes have already been mentioned above by means of which hard particles can be applied to at least one of the said components or one of the said joining partners according to the invention. With regard to the aforementioned plasma blasting, the plasma atmospheric pressure blasting process, the low-pressure plasma blasting process, or the vacuum plasma blasting process can be advantageously used, for example.

[0018] As for a material for the hard particles provided according to the invention, in addition to the aforementioned silicon carbide, NiSiC (nickel silicon carbide) or a nickel diamond powder are suitable, as are steel, for example in the form of angular particles from cast stainless steel (called Cr grit), angular chilled cast iron (with a martensitic structure), or corundum particles (made of aluminum oxide with SiO2 content). In principle, it is disclosed that the hard particles can be applied to a harder material of one of the two components or joining partners, which then penetrate into a softer material of the other component or joining partner when the joining partners are clamped against each other. However, such a material assignment or material combination is by no means mandatory.A series of tests has shown that the aforementioned introduction of hard particles into the joining partner consisting of a harder material in a joining arrangement according to the invention is advantageous when the hardness difference between the materials of the joining partners involved is relatively high. Conversely, when the hardness difference between the materials of the joining partners involved is relatively small, better results were achieved with a joining arrangement according to the invention in which the hard particles are introduced into the joining partner consisting of the somewhat softer material (before joining and clamping the joining partners against each other).

[0019] Preferably—but expressly not mandatory—the hard particles can be applied to at least one of the said surfaces in a manner that is at least approximately abrasion-resistant, for example, as already mentioned, by means of a blasting process. However, it is also possible in principle to apply such hard particles with only a slight adhesion to at least one of the said surfaces, after which they can dig proportionally into both surfaces simultaneously when the components are clamped against each other.

[0020] In various test series, it has been shown that the desired effect of the hard particles according to the invention increases with increasing mileage of a vehicle in which joining partners in the body structure or in the interior structure are designed according to the invention, i.e. the longer such a vehicle is operated, the better the intended effect - at least over the first 50,000 km of driving distance - namely a reduction in the otherwise occasionally occurring cracking or creaking noises and / or a measurable increase in stiffness or strength (of the corresponding connection arrangement). It has proven advantageous if, in the case of a material pairing of high hardness, i.e. when the joining partners that are separably clamped against each other are each made of a relatively hard material (e.g. steel), hard particles with a size ("diameter") in the range of 10 - 30 micrometers (µm) are used to a moderate extent, i.e.with a surface area in the order of magnitude of 10% distributed over the (common) contact surface of the joining partner(s). However, if the joining partners themselves consist of a relatively soft material, such as an aluminum alloy, hard particles with a size (“diameter”) in the range of 30 - 70 micrometers (µm) with a higher surface area in the order of magnitude of 20% of the common contact surface of the joining partner(s) have proven to be advantageous. And if one of the joining partners consists of a harder material and the other of a considerably softer material, hard particles with an average grain size in the order of magnitude of 20 - 40 µm are preferred, covering approximately 15% of the common contact surface.

[0021] Deviating from the aforementioned embodiment, in which the hard particles are distributed substantially evenly over the entire contact surface of one (or, in the assembled state, both joining partners), it may also be advantageous, depending on the application, to distribute the hard particles unevenly over the contact surface. Thus, if several fastening elements in the form of screws are provided that penetrate the contact surfaces of the joining partners in holes that usually run perpendicular to them and thereby clamp the joining partners against each other, the hard particles can only be applied in the immediate vicinity of the screws on at least one of the contact surfaces (before the joining partners are joined).In the immediate vicinity of these screws, the highest surface pressure is present across the entire contact surface after the joining partners have been clamped against each other, and this means that when the joining partners are clamped, the hard particles are pressed into the other joining partner as best as possible. With certain material pairings of the joining partners or in certain applications, i.e. when connecting certain joining partners to one another, it may however be necessary to clamp the joining partners against each other as strongly as possible, for example for reasons of tightness (namely to prevent water molecules from penetrating the joint gap), so that the hard particles should then preferably be located away from the said screws, i.e. excluding the immediate vicinity of the screws in the contact surface. A connecting arrangement according to the invention can, for example,preferably be provided between one of the following (and already mentioned as an example at the beginning) pairings of joining partners of a vehicle: Between a body section and a support or strut which introduces a force and to which or into it at least one vehicle component is fastened. Between a body section and a bearing element of at least one vehicle component. Between a body section and a bearing element of a wheel suspension. Between a body bulkhead and a spring strut dome. Between a body bulkhead and a body support and / or a shear field. Between a spring strut dome and a support strut and / or a body support and / or an engine mount. In a hinge arrangement for a door or flap itself or in connection with such a door or flap with a body structure part.In a seat assembly or a seat rail itself or in connection with such a seat assembly or a body structure part.

[0022] The attached single figure shows only, in principle, greatly enlarged sections of a section in the connection area between a second joining partner 2 and a first joining partner 1 of a connection arrangement according to the invention, wherein the second joining partner 2 rests with its contact surface 2a on the counter surface or contact surface 1a of the first joining partner 1.Not shown in the figures is a screw connection by means of one or more screw(s) as detachable fastening element(s), by means of which the second joining partner 2 is clamped against the first joining partner 1 in the manner of a flange connection and held thereto, wherein the screw or screws can be located within the contact surfaces 1a, 2a of the joining partners 1, 2 or also outside these contact surfaces 1a, 2a and usually run in suitable bores provided in the joining partners 1, 2, the axes of which, like the longitudinal axes of the said screws, usually run perpendicular to the contact surfaces 1a, 2a. Depending on the individual shape of the joining partners 1, 2, the joining partners 1, 2 can extend further beyond the actual contact surfaces 1a, 2a in the direction of the plane of the contact surfaces 1a, 2a, but in any case only rest on one another with these in the region of the contact surfaces.The contact surfaces 1a, 2a do not have to be flat.

[0023] Before depicting the aforementioned screw connection arrangement and thus before mounting the second joining partner 2 on the first joining partner 1 or before clamping the joining partners 1, 2 against each other, hard particles 3 were applied to the contact surface 1a of the first joining partner 1. These hard particles 3 protrude at least partially into the counter surface or contact surface 2a of the second joining partner 2 due to the clamping assembly. The hard particles 3 are also held on the contact surface 1a by a nickel adhesion promoter layer 4. Due to this thin nickel adhesion promoter layer 4, a micro-gap is created between the two components 1, 2, shown here significantly enlarged. In reality, this micro-gap is practically non-existent or can approach "zero." In particular, such an adhesion promoter layer is not required; rather, it is an optional feature.The hard particles 3 with their (optional) adhesion promoter layer 4 are applied to the joining partner 1 already provided with the coating 15. Due to the tensioning of the joining partners 1, 2 against each other, they only penetrate into the coating 25 of the joining partner 2 without penetrating into its actual surface, ie the one without the coating 25.

Claims

[1] A connecting arrangement between separably clamped joining partners (1, 2) in the body structure or in the interior structure of a vehicle, wherein the joining partners (1, 2) are clamped against each other via their contact surfaces (1a, 2a) by means of at least one detachable fastening element, wherein hard particles (3) are applied to the contact surface (2a, 1a) of at least one of the joining partners (2, 1) before the production of the connecting arrangement and thus before the clamping assembly of the joining partners (1, 2) and the fastening element, which hard particles (3) protrude at least partially into the other contact surface (1a, 2a) of the other joining partner (1, 2) as a result of the clamping assembly, and wherein both joining partners are provided with a coating, characterized bythat the connecting arrangement is designed in such a way that the hard particles (3) penetrate essentially completely into the coating of a coated joining partner (1, 2) when applied to this joining partner (1, 2) and only develop their effect when the two joining partners (1, 2) are clamped together, in that they penetrate into the coating (15, 25) of the other joining partner (1, 2) as a result of the clamping, without penetrating the actual surface of this joining partner (1, 2), since the thickness of the coating (15, 25) is slightly reduced by the clamping of the two joining partners (1, 2), while the height of the hard particles (3) does not undergo any change when the joining partners (1, 2) are clamped. [2] Connecting arrangement according to claim 1, wherein the hard particles (3) are applied in an abrasion-resistant manner to at least one of the contact surfaces (2a, 1a). [3] Connecting arrangement according to one of the preceding claims, wherein the hard particles (3) used are particles with a size of 1 - 70 µm, the surface of which has a plurality of corners and edges. [4] Connecting arrangement according to one of the preceding claims, wherein the hard particles (3) consist of a steel material or of corundum or of silicon carbide or Ni-SiC (in the form of a nickel-diamond coating). [5] Connecting arrangement according to one of the preceding claims, wherein the hard particles (3) are applied distributed over the entire contact surface (1a, 2a). [6] Connecting arrangement according to one of claims 1-4 with a plurality of fastening elements in the form of screws penetrating the contact surfaces (1a, 2a) of the body section (1) and the joining partner (2) and clamping them against each other, wherein the hard particles (3) are applied to at least one of the contact surfaces (1a, 2a) either only in the immediate vicinity of the screws or excluding the immediate vicinity of the screws. [7] Connecting arrangement according to one of the preceding claims, wherein the joining partner (1, 2) is at least one of the following components: • Body section and a support or strut introducing a force into it, to which or which at least one vehicle component is attached • Body section and bearing element of at least one vehicle component • Body section and bearing element of a wheel suspension • Body bulkhead and strut tower • Body bulkhead and body support and / or shear panel • Suspension strut dome (front / rear) and support strut and / or body support and / or engine support • Hinge arrangement for a door or flap itself or in conjunction with a body structure part • Seat assembly or seat rail itself or in conjunction with a body structure part [8] Method for producing a connecting arrangement according to one of the preceding claims, wherein the joining partners (1, 2) are clamped against each other via their contact surfaces (1a, 2a) by means of at least one detachable fastening element, wherein hard particles (3) are applied to the contact surface (2a, 1a) of at least one of the joining partners (2, 1) before the production of the connection arrangement and thus before the clamping assembly of the joining partners (1, 2) and the fastening element, which hard particles (3) protrude at least partially into the other contact surface (1a, 2a) of the other joining partner (1, 2) as a result of the clamping assembly, and wherein both joining partners are provided with a coating, characterized by that the hard particles (3) during When applied to a coated joining partner (1, 2), they penetrate essentially completely into the coating of this joining partner (1, 2) and only develop their effect when the two joining partners (1, 2) are clamped together, in that they penetrate into the coating (15, 25) of the other joining partner (1, 2) as a result of the clamping, without penetrating the actual surface of this joining partner (1, 2), since the thickness of the coating (15, 25) is slightly reduced by the clamping of the two joining partners (1, 2), while the height of the hard particles (3) does not undergo any change when the joining partners (1, 2) are clamped.

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