Method for connecting two components, and component composite

Abstract

The invention relates to a method for connecting two components (14, 16), in which two component surfaces (22, 23) of the components (14, 16) to be connected to one another in a joining region (12) are heated by a radiation source (32), wherein, at least in the joining region (12), the first component (14) is made of plastic and the second component (16) is made of metal, and wherein the two component surfaces (22, 23) are preferably pressed against one another with a pressing force (F) acting perpendicular to the component surfaces (22, 23).

Description

[0001] Description

[0002] Method for joining two components and component composite

[0003] Technical area

[0004] The invention relates to a method for joining two components using a radiation source, which allows for joining components in a material-friendly and media-tight manner, particularly those in which one component is heat-sensitive, for example, due to temperature-sensitive components arranged in the respective component. Furthermore, the invention relates to a component assembly produced by a method according to the invention.

[0005] State of the art

[0006] From DE 102016 209 950 A1, the applicant discloses a method for joining two components with the features of the preamble of claim 1. This known method is characterized in that the two components to be joined, or their component surfaces, are initially aligned at a distance from one another. A radiation source is then introduced into the space formed between the two component surfaces, and the two component surfaces are subsequently heated by the radiation source. During heating, the material of a first component, made of plastic, is heated above its crystallite melting temperature. The second component, made of metal, has a structured component surface.After heating the two component surfaces, the radiation source is removed from the gap between them, and the two component surfaces are pressed together with a joining force until the material of the plastic component solidifies. During the pressing process, the softened or liquefied material of the first component comes into active contact with the structure of the second component, thus achieving the desired strong and tight connection between the two components after the material of the first component solidifies.

[0007] Disclosure of the invention

[0008] The inventive method for joining two components with the features of claim 1 has the advantage that it can also be used to join components in which, in particular, the second component made of metal has, for example, components in its interior that must not be heated above a certain temperature in order to avoid damage or pre-damage to the components. Such damage or pre-damage is avoided in the inventive method by the short required exposure time of the radiation source to the metallic component, which has a high thermal conductivity toward the first component made of plastic.

[0009] In light of the above explanations, a method according to the invention for joining two components with the features of claim 1 therefore provides that the radiation source is directed onto an exposure zone of the second component located outside the joining zone, so that heat is introduced into the joining zone by heat conduction from the exposure zone on the second component into the joining zone between the two component surfaces. Preferably, it is further provided that the two component surfaces of the components are pressed against each other, optionally with the interposition of a high-temperature curing adhesive, before the radiation source acts on the components.

[0010] Advantageous further developments of the method according to the invention for connecting two components are listed in the subclaims.

[0011] In order to enable the shortest possible heat transfer path from the area of ​​influence of the radiation source to the joining area, on the one hand, and to minimize the thermal load on the components and the process duration, on the other hand, it is preferably provided that the second component projects laterally beyond the first component, and that the area of ​​influence is preferably aligned directly or at a short distance next to the joining area or the first component.

[0012] In order to enable the most homogeneous energy input possible into the first component or the joining area, in particular so that the material of the first component melts as simultaneously as possible in the joining area, it is provided that the area of ​​action has a closed contour and that at least one laser beam is used as the radiation source, which is guided along the contour, preferably by repeatedly traversing the contour.

[0013] In particular in the case of component assemblies where, for geometric or other reasons, the impact area cannot have a closed contour, the contour can also be designed as a non-closed or open contour.

[0014] In a particularly preferred development of the last proposal, in which the thermal energy introduced into the joining area can be controlled very precisely as required, it is provided that the thermal energy coupled into the exposure area by the at least one laser beam is changed, in particular reduced, over the exposure time and / or that the thermal energy is changed depending on the distance of the exposure area from the joining zone, such that the thermal energy is increased at a greater distance.

[0015] The method according to the invention can also be used to join the two components together with the interposition of a high-temperature curing adhesive, wherein the adhesive is activated or cured by the radiation source. For this purpose, a high-temperature curing adhesive is arranged in the joining area between the two component surfaces, which is activated by the action of the radiation source, wherein the heating of the first component is such that its temperature is below the crystallite melting temperature of the first component. Such a method is therefore particularly suitable for particularly temperature-sensitive components in the first component made of plastic, where the temperature increase required to activate the adhesive is lower than that required to reach the crystallite melting temperature.It should also be mentioned that when using adhesive, a laser beam source should preferably be used as the radiation source, as this allows the highest temperature gradients to be achieved.

[0016] In the variant in which no such adhesive is used, the two components are pressed directly against one another in the joining area, the second component is a component that has a surface structure in the joining area, and by heating the first component, consisting of the thermoplastic material, to a temperature above its crystallite melting temperature, the material of the first component melts in certain areas and penetrates the surface structure of the second component. The surface structure not only enlarges the surface in the joining area, but also makes it possible to form undercuts or similar geometric shapes through the surface structure, for example, which enables a good mechanical connection between the two components through positive locking.

[0017] In order to introduce a high level of thermal energy into the second component as quickly as possible, the material of the second component can be melted in the area exposed to the radiation source, forming a weld seam. The weld penetration depth preferably amounts to a maximum of 70% of the wall thickness of the second component in the area exposed. Limiting the weld penetration depth to a maximum of 70% of the wall thickness can therefore be useful so that the weld seam maintains the strength and geometry of the second component in the area exposed. Depending on the application, however, penetration welds may also be useful, for example, to simultaneously create structural connections between components.

[0018] Alternatively, it can be provided that the material of the second component is not melted in the exposure zone. This method has the particular advantage that, after the two components have been joined, a visually identical or homogeneous appearance is achieved in the exposure zone compared to the remaining areas of the second component. Particularly with the last two methods mentioned, it can also be provided that the radiation source acts on a structure or coating of the second component formed in the exposure zone to improve heat transfer or the coupling of thermal energy (increased absorption).

[0019] Furthermore, the invention also encompasses a component assembly consisting of two components that are connected to one another according to a method according to the invention described so far. The component assembly according to the invention is characterized in particular in that the first component is a connector body and the second component is a housing. In particular, such a component assembly is designed as part of a camera, in particular as a vehicle interior camera or as a vehicle exterior camera. Such vehicle cameras are, for example, components of vehicles that are designed for at least partially autonomous ferry operation. Alternatively, the component assembly can also form a control unit in which a connector connection body is connected to a (metallic) housing.

[0020] Further advantages, features and details of the invention will become apparent from the following description of preferred embodiments of the invention and from the drawings.

[0021] Short description of the drawings

[0022] Fig. 1 shows a component assembly during the production of the connection of two components in a perspective view,

[0023] Fig. 2 is a plan view of a partial area of ​​a component according to Fig. 1 with a surface structuring,

[0024] Fig. 3 is a perspective sectional view of the component assembly according to Fig. 1 and

[0025] Fig. 4 and Fig. 5 each in plan view, different methods for moving a radiation source in the region of the component assembly according to Fig. 1.

[0026] Embodiments of the invention

[0027] Identical elements or elements with the same function are provided with the same reference numbers in the figures.

[0028] Fig. 1 shows a component assembly 10 comprising two components 14, 16 joined together in a joining region 12. The first component 14 is, for example, and not by way of limitation, a plug body 15 made of a thermoplastic material. The second component 16 is, for example, a housing 17 made of metal, for example aluminum, steel, or the like, which in the exemplary embodiment is approximately cubic. The second component 16 or, for example, the housing 17 can contain electronics or electronic components (not shown), which are characterized in particular by the fact that their temperature must not exceed a certain value in order to ensure their functionality over the service life of the component assembly 10. Heat-sensitive components can also be present in the first component 14.The material of the second component 16 has a higher melting temperature than the material of the first component 14.

[0029] From Figs. 1 and 3, it can also be seen that the housing 17 has a (flat) housing cover 20 on the side facing the first component 14. The housing cover 20 encloses or covers an interior space arranged in the housing 17, in which further optical, electrical, or other components can be arranged.

[0030] The component assembly 10 described so far is, in particular, a component of a camera, in particular a vehicle interior camera or a vehicle exterior camera, or forms such a camera. However, it is also conceivable for the component assembly 10 to form a control unit, wherein the first component 14 is, for example, a plastic housing with housing closures, and the second component 16 is a metal base body of the housing 17.

[0031] The first component 14 or the plug body 15 has, purely by way of example, a first component surface 22 in the joining region 12 according to the illustration in Figs. 1 and 3, which is designed in the manner of a rectangular frame with rounded corners, while the second component 16 or the housing cover 20 forms a second component surface 23 in the joining region 12. The first component 14 also has an interior space with a first through-opening 24 formed on the side facing the second component 16, which is aligned with a second through-opening 26 in the second component 16 in order to enable a passage between the two components 14, 16, for example for the passage of electrical connection components or the like.

[0032] Fig. 2 shows the second component 16 in the region of the housing cover 20 in a top view. In particular, a region 28 formed corresponding to the outer contour of the first component 14 with the second through-opening 26 can be seen. Furthermore, it can also be seen from Figs. 1 and 2 that the second component 16 projects laterally beyond the first component 14 in a direction parallel to the joining region 12. The region 28 is provided with a surface structuring 30, which was produced, for example, by laser processing and which—as is known per se—can have a microstructure overlaid by a nanostructure.

[0033] 1 and 3 show the two components 14, 16 during the joining of the two components 14, 16. The first component 14 is subjected to a contact pressure force F running perpendicular to the joining region 12 against the housing cover 20 or against the second component 16. The components 14, 16 are joined by heating the material of the first component 14 in the region of the joining zone 12 or the first component surface 22 to a temperature that is above the crystallite melting temperature of the material of the first component 14. As a result, the material of the first component 14 melts in the region of the first component surface 22 and enters the surface structuring 30 of the second component 16 or the housing cover 20. The contact pressure F is preferably maintained until the material of the first component 14 has completely solidified.

[0034] The heating or melting of the material of the first component 14 is carried out by at least one radiation source 32, in particular by at least one laser beam LS. The laser beam LS is directed in a manner known per se onto an area of ​​action 34 which extends outside the first component 14. Fig. 1 shows in particular that the laser beam LS is guided along a closed contour 36 which runs parallel to and at a short distance a from the outer contour 37 of the first component 14 or directly next to the first component 14 in the region of the first component surface 22. In a modification of the exemplary embodiment, the contour 36 can, however, also be designed as an open or non-closed contour 36, depending on the application.

[0035] It should also be noted that the aforementioned surface structuring 30 can also extend into the area of ​​the contour 36, or that a surface structuring that is separate from the surface structuring 30 or separate, possibly having a geometry, can be formed in the area of ​​the contour 36. Alternatively, a coating can be provided to increase heat absorption in the impact area 34. This enables better heat transfer or greater energy coupling into the (metallic) second component 16 by the laser beam LS.

[0036] When the contour 36 is traversed, in particular several times, by the at least one laser beam LS, heat is transferred from the area of ​​action 34 in the direction of the first component surface 22 in order to heat the material of the first component 14 above its crystallite melting temperature. The contour 36 is traversed, in particular several times, by the laser beam LS, for example, at a speed v of the laser beam LS in the plane of the contour 36 of between 0.1 m / s and 10 m / s, preferably between 0.5 m / s and 5 m / s. The temporal profile of the laser radiation introduced into the surface of the second component 16 can also be varied. In particular, it is advantageous if the power of the laser beam LS is greater at the beginning than towards the end of the action of the laser beam LS. Finally, the power of the laser beam LS can be increased, in particular in the case of complex orcomplicated contours 36 or first component surfaces 22 with different sized cross-sections in the joining area 12, can also be varied depending on the distance a, such that at a larger distance a a higher heat output or a higher laser power is used than at a small distance a.

[0037] The power of the laser beam LS can also vary depending on the application. As shown in Fig. 3, the power of the laser beam LS can be so high that the material of the second component 16 is melted in the area of ​​impact 34 or in the area of ​​the contour 36, forming a weld seam 38. Preferably, the penetration depth t of the weld seam 38 is a maximum of 70% of the wall thickness d of the housing cover 20 of the second component 16. Alternatively, the power of the laser beam LS can also be selected such that the material of the second component 16 is not melted.

[0038] 4 and 5 show different strategies for heating or applying the at least one laser beam LS to the area of ​​the contour 36. Fig. 4 shows that a single laser beam LS is used, which, starting at a starting point S in the area of ​​the contour 36 to be created, traces the contour 36 several times in the direction of the arrows shown. In contrast, Fig. 5 shows that the contour 36 is created with the aid of two laser beams LS1 and LS2. The two starting points S1 and S2 are arranged on opposite sides of the contour 36, and each of the two laser beams LS1 and LS2 travels (several times) a distance that corresponds to half the length of the contour 36.

[0039] In the component assembly 10 described above, the two components 14, 16 are directly connected to one another or pressed against one another. In an embodiment of the invention (not shown), however, it can also be provided that a high-temperature curing adhesive in the form of an adhesive layer is arranged between the two component surfaces 23, 23 of the two components 14, 16 in the joining region 12. In this case, the heat input via the at least one laser beam LS serves to heat the high-temperature curing adhesive to its activation temperature. It is essential that the material of the first component 14 in the region of the first component surface 22 is not, and does not have to be, heated above its crystallite melting temperature. Furthermore, in such an embodiment, a surface structuring 30 in the joining region 12 between the two components 14, 16 can optionally be dispensed with.

[0040] The method or the component assembly 10 described so far can be modified or altered in many different ways without deviating from the inventive concept.

Claims

Claims 1. A method for joining two components (14, 16), in which two component surfaces (22, 23) of the components (14, 16) to be joined together in a joining region (12) are heated by a radiation source (32), wherein at least in the joining region (12) the first component (14) is made of plastic and the second component (16) is made of metal, characterized in that the radiation source (32) is directed onto an exposure region (34) of the second component (16) arranged outside the joining region (12), so that the heat is introduced into the joining region (12) by heat conduction from the exposure region (34) into the joining region (12).

2. Method according to claim 1, characterized in that the two component surfaces (22, 23) are pressed against one another with a contact pressure force (F) acting perpendicular to the component surfaces (22, 23), and / or that the two component surfaces (22, 23) are pressed against one another, optionally with the interposition of a high-temperature curing adhesive, before the radiation source (32) acts on the components (14, 16).

3. Method according to claim 1 or 2, characterized in that the second component (16) projects laterally beyond the first component (14), and in that the action region (34) is preferably aligned directly or at a short distance (a) next to the joining region (12) or the first component (14).

4. Method according to claim 1 or 2 or 3, characterized in that that the action area (34) has a closed contour (36), and that the radiation source (32) generates at least one laser beam (LS; LS1, LS2) which is guided along the contour (36), preferably by repeatedly traversing the contour (36).

5. Method according to claim 4, characterized in that the thermal energy coupled into the action region (34) by the at least one laser beam (LS; LS1, LS2) is changed, in particular reduced, over the duration of the action, and / or that the thermal energy is changed as a function of the distance (a) of the action region (34) from the joining zone (12), such that the thermal energy is increased at a greater distance (a).

6. Method according to one of claims 1 to 5, characterized in that a high-temperature curing adhesive is arranged in the joining region (12) between the two component surfaces (22, 23), which is activated by the action of the radiation source (32), wherein the heating of the first component (14) is such that its temperature is below the crystallite melting temperature of the material of the first component (14).

7. Method according to one of claims 1 to 5, characterized in that the two components (14, 16) are pressed directly against one another in the joining region (12), that a second component (16) is used as the second component (16) which has a surface structuring (30) in the joining region (12), and that by heating the first component (14) consisting of a thermoplastic material to a temperature above its crystallite melting temperature, the material of the first component (14) melts in regions and penetrates into the surface structuring (30) of the second component (16).

8. Method according to one of claims 1 to 7, characterized in that that the material of the second component (16) is melted in the area of ​​action (34) to form a weld seam (38), wherein the welding depth (t) preferably has a maximum of 70% of the wall thickness (d) of the second component (16) in the area of ​​action (34).

9. Method according to one of claims 1 to 7, characterized in that the material of the second component (16) is not melted in the area of ​​action (34).

10. Method according to one of claims 1 to 9, characterized in that the radiation source (32) acts on a structuring or coating of the second component (16) formed in the area of ​​action (34).

11. Component assembly (10) consisting of two components (14, 16) which are connected to one another by a method according to one of claims 1 to 10 12. Component assembly (10) according to claim 11, characterized in that the first component (14) is a plug body (15) and the second component (16) is a housing (17).

13. Component assembly according to claim 11 or 12, characterized in that the component assembly (10) forms a camera, in particular a vehicle interior camera or a vehicle exterior camera, or a part of such a camera, or that the component assembly (10) forms a control unit.

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