LIGHT MODULE FOR A MOTOR VEHICLE LIGHTING DEVICE, AND METHOD FOR PRODUCING A LIGHT MODULE

Abstract

A light module for a motor vehicle lighting device, at least comprising an LED lamp, metal conductor tracks for electrically contacting the LED lamp, a carrier body on which the LED lamp and the conductor tracks are arranged, and a metal heat sink. The carrier body being form-fittingly connected to the heat sink. The carrier body comprises an electrically insulating and thermally conductive composite material.

Claims

1. A light module for a motor vehicle lighting device, the light module comprising: an LED lamp; metal conductor tracks for electrical contacting the LED lamp; a carrier body on which the LED lamp and the conductor tracks are arranged; and a metal heat sink, wherein the carrier body is form-fittingly connected to the heat sink, and wherein the carrier body comprises an electrically insulating and thermally conductive composite material.

2. The light module according to claim 1, wherein the carrier body has an electrical insulation resistance of at least 10.sup.7 and/or the composite material has a thermal conductivity of at least 4 W/mK, or at least 10 W/mK.

3. The light module according to claim 1, wherein the composite material has a matrix of a plastic or a polyamide or another semi-crystalline plastic, and metal, ceramic and/or graphitic fillers, wherein the fillers have a globular shape and a homogeneous distribution in the matrix.

4. The light module according to claim 1, wherein the carrier body has a thickness of 0.5 to 5 millimeters, or 1 to 3 millimeters.

5. The light module according to claim 1, wherein the heat sink has at least one metal heat dissipation element for contacting the at least one LED lamp, wherein the heat dissipation element protrudes from the joining surface of the heat sink and is laterally enclosed by the carrier body such that via the heat dissipation element, a thermal bridge is created between the LED lamp and the heat sink.

6. The light module according to claim 1, wherein the light module comprises at least one metal heat spreading element which is at least partially enclosed by the composite material of the carrier body.

7. The light module according to claim 1, wherein the carrier body forms a joining zone with the heat sink, wherein the heat sink has a joining surface with microscale and/or nanoscale cavities in the joining zone, which the composite material of the carrier body fills by forming a form-fitting connection, preferably with the formation of undercuts.

8. A method for producing a light module for a motor vehicle lighting device according to claim 1, the method comprising: providing the metal heat sink; inserting microscale and/or nanoscale cavities into a joining surface of the heat sink; injection molding the carrier body from the electrically insulating and thermally conductive composite material, the composite material of the carrier body filling the cavities in the joining surface of the heat sink thereby forming a positive connection; applying the metal conductor tracks to the carrier body; and applying the at least one LED lamp.

9. A method for producing a light module for a motor vehicle lighting device according to claim 1, the method comprising: providing the metal heat sink; inserting microscale and/or nanoscale cavities into the joining surface of the heat sink; providing the carrier body; thermal direct joining of the carrier body with the heat sink, wherein the composite material of the carrier body fills the cavities in the joining surface of the heat sink, forming a positive connection; applying the metal conductor tracks to the carrier body; and applying the at least one LED lamp.

10. A method for producing a light module for a motor vehicle lighting device according to claim 1, the method comprising: provision the metal heat sink; inserting microscale and/or nanoscale cavities into the joining surface of the heat sink; providing a carrier foil made of an electrically insulating and thermally conductive composite material; thermal direct joining of the carrier foil with the heat sink, wherein the composite material of the carrier foil fills the cavities in the joining surface of the heat sink, forming a positive connection; providing the carrier body; thermal direct joining of the carrier body with the carrier foil; and applying the at least one LED lamp and the metal conductor tracks to the carrier body.

11. The method according to claim 9, wherein the thermal direct joining is carried out by heating the carrier body and/or the carrier foil in the joining zone by laser radiation, by infrared radiation, by convective heat supply and/or by an inductive or contacting heating of the heat sink.

12. Method according to claim 9, wherein the carrier body is provided with attached metal conductor tracks and at least one LED lamp.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0029] 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:

[0030] FIG. 1 shows an example of the light module according to the invention, and

[0031] FIG. 2 shows a further example.

DETAILED DESCRIPTION

[0032] The figures show schematic cross-sectional views of an example of the inventive light module 100 for a motor vehicle lighting device, respectively the LED lamps 1, the metal conductor tracks 2 for the electrical contacting of the LED lamps 1, the carrier body 3, on which the LED lamps 1 and the conductor tracks 2 are arranged, as well as the metal heat sink 4, wherein the carrier body 3 is form-fittingly connected to the heat sink 4. According to the invention, the carrier body 3 has the electrically insulating and thermally conductive composite material 30.

[0033] Due to the pronounced thermal conductivity of the composite material 30, which is at least 4 W/mK, in particular more than 10 W/mK, for example, extremely efficient heat dissipation takes place through the carrier body 3 into the heat sink 4 during operation of the LED lamps 1. The thickness D of the carrier body 3 is preferably 1-3 millimeters, so that the carrier body 3 has a sufficiently high heat capacity to distribute and dissipate the resulting heat flow without thermal damage.

[0034] The inset of FIG. 1 shows an enlarged cross-sectional view of the full-surface joining zone 34 between the heat sink 4 and the carrier body 3. The heat sink 4 has a joining surface in the joining zone 34 with the microscale and/or nanoscale cavities 41, which the composite material 30 of the carrier body 3 fills to form a form-fitting connection. Due to the bulging shape of the cavities 41, the penetrated composite material 30 forms undercuts of the carrier body 3.

[0035] In the example of FIG. 2, the heat sink 4 has the metal heat dissipation elements 5, to which the LED lamps 1 are soldered as examples. The heat dissipation elements 5 are designed in one piece and uniform in terms of material with the heat sink 4 and are laterally enclosed by the support body 3, so that a direct metal heat bridge is formed between the LED lamps 1 and the heat sink 4 by means of the heat dissipation elements 5, which enables particularly fast heat dissipation.

[0036] Furthermore, the light module 100 includes the metal heat spreading element 6, which is enclosed by the composite material 30 of the carrier body 3 and contributes to the improvement of the lateral heat spread within the carrier body 3.

[0037] The invention is not limited in its execution to the examples given above. Rather, a number of variants are conceivable, which make use of the solution presented even in the case of fundamentally different designs. All features and/or advantages arising from the claims, the description or the drawings, including design details, spatial arrangements and method steps, can be essential to the invention both on their own and in the most diverse combinations.

[0038] 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.