METHOD FOR PRODUCING A JOINT CONNECTION BETWEEN A LIGHT-GIVING/OPTICS PLASTIC COMPONENT AND A METAL COMPONENT

Abstract

A method for manufacturing a joining connection between a luminously efficacious part and a metal component of a lighting device of a vehicle. A microstructure is generated in a joining surface of the metal component, the microstructure having undercuts with respect to the joining surface. The plastic material of the plastic part is softened in an area of the complementary joining surface near the surface with the aid of an introduction of heat. The plastic part and the metal component are pressed together with a pressure force in such a way that a portion of the softened plastic material penetrates the undercuts of the microstructure. The plastic material of the plastic part is cooled thereby forming a new strength of the softened plastic material of the plastic part.

Claims

1. A method for manufacturing a joining connection between a luminously efficacious part 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 a plastic material of a 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 such that a portion of the softened plastic material penetrates the undercuts of the microstructure; and cooling the plastic material of the plastic part to form 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 plastic 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 plastic 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 plastic 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 the luminously efficacious plastic component is designed such that it is irradiated or through-irradiated during the operation of the lighting device with the aid of at least one light beam generated by a light source in the lighting device, and/or the luminously efficacious plastic part is designed as a reflector, a light conducting body, a thick-walled optical element or a primary optical element.

8. The method according to claim 1, wherein a holder of the luminously efficacious plastic part is formed with the metal component, and/or the metal component has a diaphragm edge, with the aid of which an aperture effect is achieved.

9. The method according to claim 1, wherein the joining surface having the microstructure between the plastic part and the metal component is selected such that a thermal compensation of the location of the plastic part as a reflector, as a light-conducting body, as a thick-walled optical element or as a primary optical element relative to the installation environment is achieved with the aid of the different coefficients of thermal expansion between the plastic part and the metal component.

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

11. A joint made up of a luminously efficacious plastic 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 luminously efficacious plastic part and/or the metal component has a diaphragm edge, with the aid of which an aperture effect may be generated by a light which is adapted to be irradiated through or onto the plastic part.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0027] 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:

[0028] FIG. 1 shows a schematic cross-sectional view of the joint between the plastic part and the metal component;

[0029] FIG. 2 shows a view of a luminously efficacious plastic part in an arrangement on a metal component;

[0030] FIG. 3 shows the view of a metal component, including a diaphragm section, in an arrangement on a luminously efficacious plastic part; and

[0031] FIG. 4 shows a plastic part designed as a reflector in an arrangement on a metal component designed as a cooling body.

DETAILED DESCRIPTION

[0032] FIG. 1 shows a cross-sectional view of a joint between a plastic part 1 and a metal component 2. Plastic part 1 is illustrated in an abstracted manner and is therefore provided with a luminously efficacious design, which is not shown in further detail, and describes, for example, a reflective or transmissive optical element of a light module in a lighting device of a vehicle, for example in a headlamp. Metal component 2 may be, for example, a holder, a diaphragm or another retrofit part of the reflective or transmissive optical element, for example a cooling body.

[0033] 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 plastic part 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.

[0034] 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.

[0035] To generate the joining connection, the complementary contact area of plastic part 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. Plastic part 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 plastic 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 plastic part 1 and metal component 2 without a macroscopic form fit being necessary.

[0036] FIG. 2 shows an example of a transmissive optical element in the form of plastic part 1, into which light may be irradiated with the aid of a light source 12, and which may be coupled out again on an opposite side, as indicated by arrows. Plastic part 1 is mounted on a metal component 2, and the contact area between plastic part 1 and metal component 2 has microstructures 10, via which a connection between plastic part 1 and metal component 2 is generated using the method described above.

[0037] FIG. 3 shows a further exemplary embodiment of a joining connection between a plastic part 1 and a metal component 2, plastic part 1 being a luminously efficacious part, for example a light conducting body of a solid design. Metal component 2 is mounted on an upper side, and it includes a diaphragm section 14 having a diaphragm edge 13. The example shows a light/dark boundary 15 upon a through-irradiation of plastic part 1, which is generated with the aid of diaphragm edge 13. Microstructure 10 introduced into the contact surface of metal component 2, into which the heated plastic of plastic part 1 may penetrate, is used to fasten metal component 2 on plastic part 1, so that the illustrated structure does not require any adhesive or the like, and metal component 2 is nevertheless fixedly arranged on plastic part 1.

[0038] FIG. 4 shows an application of a plastic part 1 in the form of a reflector 16 and a metal component 2 in the form of a cooling body 17. Once again, the contact area of metal component 2 is provided with a microstructure 10, so that a reflector base 18 of reflector 16 may be mounted on the surface of cooling body 17. If light source 12 is operated, the generated contact between plastic part 1 and metal component 2 may result in an advantageous heating thereof.

[0039] 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.

[0040] 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.