METHOD FOR PRODUCING A JOINT CONNECTION BETWEEN A STRUCTURAL COMPONENT MADE OF A PLASTIC AND A METAL COMPONENT

Abstract

A method for manufacturing a joining connection between a structural part and a metal component of a lighting device of a vehicle, the method comprising at least the following steps: Generating a microstructure in a joining surface of the metal component, the microstructure having undercuts with respect to the joining surface; Softening the plastic material of the plastic part in an area of the complementary joining surface near the surface with the aid of an introduction of heat; Pressing the plastic part and the metal component together with a pressure force in such a way that a portion of the softened plastic material penetrates the undercuts of the microstructure; and Cooling the plastic material of the plastic part, forming a new strength of the softened plastic material of the plastic part.

Claims

1. A method for manufacturing a joining connection between a structural part made from a plastic and a metal component of a lighting device of a vehicle, the method comprising: generating a microstructure in a joining surface of the metal component, the microstructure having undercuts with respect to the joining surface; softening the plastic material of the structural part in an area of the complementary joining surface near the surface with the aid of an introduction of heat; pressing the structural part and the metal component together with a pressure force such that a portion of the softened plastic material penetrates the undercuts of the microstructure; and cooling the plastic material of the structural part thereby forming a new strength of the softened plastic material of the plastic part.

2. The method according to claim 1, wherein the introduction of heat is generated with the aid of contact heating elements, by a laser irradiation or by an IR irradiation.

3. The method according to claim 1, wherein material tongues, which penetrate the microstructure with the softened material, are formed when pressing together the structural part and the metal component via which a form fit and/or a force fit is/are formed with the metal component.

4. The method according to claim 1, wherein the joining surface with the microstructure is of the same size or smaller than a contact surface between the structural part and the metal component.

5. The method according to claim 1, wherein a single joining surface or multiple individually separately formed joining surfaces having the microstructure are formed on a contact surface between the structural part and the metal component.

6. The method according to claim 1, wherein the metal component is formed with the aid of an Mg alloy, an Al alloy, a Zn alloy or an Fe alloy, and/or is manufactured by a die casting method, an extrusion method, a forging method, with the aid of a machining manufacturing process and/or with the aid of a stamping/bending method.

7. The method according to claim 1, wherein a housing of the lighting device, a lens holder, a frame body, a carrier body or the like is formed with the structural part formed from plastic.

8. The method according to claim 1, wherein an optical element receptacle holder of the structural part or holding lugs of the housing of the lighting device are formed with the metal component, and/or the housing of a control unit is formed with the metal component.

9. The method according to claim 1, wherein the joining surface having the microstructure between the structural part and the metal part is selected such that a thermal compensation of the location of the structural part is achieved with the aid of the different coefficients of thermal expansion between the structural part and the metal component.

10. The method according to claim 1, wherein the structural part and the metal component are pressed against each other with a handling system, the handling system being controlled in such a way that the location of the structural part is positioned in a compensating position on or at the metal component for the purpose of compensating for tolerances.

11. A joint formed of a structural part and a metal component manufactured via the method according to claim 1.

12. The joint according to claim 11, wherein the metal component forms a holder of the structural part, and/or the metal component forms a holding lug for the holding accommodation of a lighting device in the structure of a vehicle.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus, are not limitive of the present invention, and wherein:

[0027] FIG. 1 shows a schematic cross-sectional view of the joint between the structural part made form a plastic and the metal component;

[0028] FIG. 2 shows a view of a structural part designed as a housing of a headlamp and a control unit;

[0029] FIG. 3 shows the view of a structural part as a housing and a holder made up of the metal component; and

[0030] FIG. 4 shows a schematic view of a headlamp, including its housing, which forms the structural part made from plastic, and holding lugs formed on the housing, which form the metal component.

DETAILED DESCRIPTION

[0031] FIG. 1 shows a cross-sectional view of a joint between a structural part made from plastic 1 and a metal component 2. Structural part made from plastic 1 is shown in an abstract manner and is therefore designed, not illustrated in greater detail, as a carrier element, as a holding element or, for example, as a housing of a lighting device of a vehicle, for example a headlamp. Metal component 2 may form, for example, a reinforcement, a holder, a holding lug or the like.

[0032] Microstructures 10, which run at an incline starting from the surface into the body of metal component 2, are introduced into the surface of metal component 2 used as a contact surface to structural part made from plastic 1, the angle of inclination of the microstructures pointing in different directions, discernibly illustrated by way of example with left-side microstructures 10, with right-side microstructures 10 oriented in the opposite direction.

[0033] Microstructures 10 have been introduced into metal component 2, for example using a laser-based material removal method or an etching method. The representation of microstructure 10 is provided with an oversized design with reference to the thickness of metal component 2, and it is sufficient if microstructure 10 runs into the material at a depth of, for example, less than 1,000 μm, less than 500 μm or less than 200 μm starting from the surface.

[0034] To generate the joining connection, the complementary contact area of structural part made from plastic 1, i.e. the contact area opposite metal component 2, is first heated, for example using contact heating elements, by means of laser irradiation or by means of IR irradiation. Structural part made from plastic 1 is pressed with its subsequently softened surface onto microstructure 10 of metal component 2, applied pressure force F being represented by arrows. A portion of the softened plastic material of structural part 1 then penetrates microstructure 10 and forms material tongues 11, which interlock with undercut microstructure 10 after a cooling of plastic part 1 and thus form a form fit and possibly additionally a friction fit. A mechanically loadable joining connection is generated thereby between structural part made from plastic 1 and metal component 2 without a macroscopic form fit being necessary.

[0035] FIG. 2 shows an example of a portion of a housing 14, which forms structural part 1 made from a plastic and which may be housing 14 of a headlamp. An opening 28 is introduced into housing 14, and a control unit 21 is arranged on the outside in front of opening 28, so that, for example, a housing 20 of control unit 21 closes opening 28.

[0036] Housing 20 of control unit 21 forms, for example, metal component 2, which is joined to structural part 1 made from plastic, which forms structural component and is formed by housing 14.

[0037] In a joining area, the surface of housing 20 of control unit 21 is provided with a microstructure 10, so that control unit 21 may be arranged on the outside of housing 14 of the headlamp, using the method according to the invention, and thus also closes opening 28. An inner cable conduit 27 is inserted into the interior of housing 14, which may be connected, for example, to an illuminant or an actuator, and control unit 21 includes an outer cable conduit 29, which may be connected, for example, to the vehicle itself.

[0038] The joining area defined by microstructure 10 surrounds opening 28, for example completely, so that the latter is sealed liquid- and gas-tight upon the arrangement of control unit 21 and after the manufacturing of the joining connection.

[0039] A mounting of the headlamp is illustrated schematically in FIG. 3, including a housing 14, and a light source 12 and an optical component 22 are accommodated in housing 14. Optical component 22 is held with the aid of an optical element holder 16, and a holder 18 extends through housing 14, which is brought out of housing 14 and which has screw holes 26, via which the headlamp may be fastened, for example, in the vehicle. Optical element holder 16 is arranged on holder 18 with the aid of contact sections 23; light source 12 is likewise accommodated on holder 18 with the aid of a carrier body 17.

[0040] Holder 18 forms, for example, a metal component 2, and housing 14 forms a structural part 1 made from a plastic, which has a joining connection to holder 18 manufactured in the manner according to the invention. Within the meaning of the invention, optical element holder 16 is further mounted on holder 18 with the aid of contact sections 23 in a manner according to the invention, using a joining connection; carrier body 17 for light source 12 may be mounted on holder 18 in the same way.

[0041] FIG. 4 shows a further example of a headlamp, including a housing 15, in a schematic view, housing 15 forming structural part 1 made from a plastic. In housing 15, an optical element receptacle 13 is configured to accommodate optical components 24, and a plastic lens is arranged on housing 15. Optical element receptacle 13 may form a metal component 2 with areas of a microstructure 10, via which optical element receptacle 13 is fastened in the interior of housing 15 in the manner according to the invention.

[0042] Holding lugs 19 made from metal are furthermore arranged on the outside of housing 15, which have particular microstructures 10 in a joining area to housing 15, via which holding lugs 19 are connected to the plastic material of housing 15 in the manner according to the invention.

[0043] The design of the invention is not limited to the preferred exemplary embodiment specified above. Instead, a number of variants are conceivable, which make use of the illustrated approach, even in fundamentally different designs. All features and/or advantages arising from the claims, the description or the drawings, including structural details, spatial arrangements and method steps, may be essential to the invention individually as well as in a wide range of combinations.

[0044] The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are to be included within the scope of the following claims.