Lighting device for motor vehicle

Abstract

The invention relates to a lighting device for a motor vehicle, in particular a headlight for a motor vehicle, comprising at least one light source, a collimating lens (1) having at least one collimating lens (4), and a secondary lens, the lighting device is arranged such that light emitted from the at least one light source passes successively through the collimating optics (1) and through the secondary optics, and wherein the collimating optics (1) comprises a first part (2) consisting of plastic and a second part (3) consisting of glass.

Description

Field of the Invention

[0001] The present invention relates to a lighting device for a motor vehicle, in particular a headlamp for a motor vehicle, as described in the preamble of claim 1, and a method for manufacturing such a lighting device. Background Art

[0002] A lighting device of the aforementioned type is known from DE 10 2018 107 213 A1. The lighting device described therein is designed as a low-beam module of a headlamp and includes three light-emitting diodes (LEDs) arranged adjacent to each other in a horizontal row, from which light is emitted during operation of the lighting device. The lighting device also includes collimating optics having three collimating lenses arranged side by side in a horizontal row. In each case, one of the collimating lenses is associated with one of the light sources such that the light emitted from one of the light sources passes through the associated collimating lens. In this case, each collimating lens has an incident surface facing the associated light source and an opposite exit surface. A diaphragm opening is provided on the incident surface of each collimating lens. The lighting device also includes secondary optics through which the light emitted from the collimating optics passes.

[0003] In the first embodiment of the headlamp described in DE 10 2018 107 213 A1, the collimating optics are formed in a rather complex manner by a collimating lens section and an extension section extending from the collimating lens section towards the light source. The collimating lens section is made of polycarbonate, while the extension section is made of a silicone material to provide thermal decoupling between the collimating lens section and the light source. The manufacture of these collimating optics made of a plurality of different plastic materials is quite expensive. In the second embodiment of the headlamp described in DE 102018 107 213A1, the collimating optics are made of glass. The manufacture of the collimating optics made of glass is also quite expensive. Summary of the Invention

[0004] It is an object of the present invention to provide a lighting device of the above type that can be manufactured inexpensively. In addition, a method for manufacturing such a lighting device is to be disclosed.

[0005] This is achieved by a lighting device of the type initially mentioned having the characterizing features of claim 1 and by a method of the type initially mentioned having the characterizing features of claim 10. The dependent claims relate to preferred embodiments of the present invention.

[0006] According to claim 1, the collimating optical device comprises a first part made of plastic and a second part made of glass. Thus, the first part may include the at least one collimating lens, and the second part may be arranged on a side of the collimating optical device facing the at least one light source. Therefore, the second part including glass can thermally decouple the first part including the at least one collimating lens made of plastic from the at least one light source. Compared with the prior art, in this case only the second part, in particular the small second part, has to be made of glass, so that the manufacturing cost of the lighting device can be reduced. In addition, compared with a collimating optical device composed of a variety of different plastic materials, the manufacturing cost can be reduced.

[0007] It may be provided that the collimating optical device has at least one aperture opening. Thus, the at least one aperture opening may be arranged on the second part of the collimating optical device, in particular on a side of the second part facing the at least one light source. Preferably, the at least one aperture opening may be formed as an opening in an opaque layer on the second part of the collimating optical device, wherein the opaque layer is in particular a metal layer. During operation of the lighting device, heat is introduced into the opaque layer by the at least one light source. Therefore, arranging the aperture opening on the side facing away from the first part improves the thermal decoupling of the first part made of plastic from the at least one light source.

[0008] It is possible that the lighting device includes a plurality of light sources, a plurality of aperture openings and a plurality of collimating lenses. In each case, one of the light sources can be associated with one of the apertures and one of the collimating lenses, such that the light emitted from the light source successively passes through the associated aperture and the associated collimating lens. For example, in this case, the light source, the aperture opening and the collimating lens can be arranged adjacent to each other in at least one row in a first direction, which corresponds to the horizontal direction when the lighting device is installed in a vehicle. In this way, a very compact module can be created, which can achieve multiple lighting functions despite its small size.

[0009] It may be provided that the second part of the collimating optical device is bar-shaped and has a longitudinal direction parallel to the first direction, in particular wherein the second part extends substantially over the entire width of the collimating optical device in the first direction. Therefore, all the aperture openings for the light sources can be arranged at the second part, which is formed as a heat-insulating glass bar.

[0010] According to claim 10, the first part of the collimating optical device is made of plastic, and the second part of the collimating optical device is attached to a side of the first part facing the at least one light source.

[0011] It is possible that the first part of the collimating optics is made of plastic by an injection molding process. If the entire first part of the collimating optics is made of the same plastic, the first part can be manufactured quite inexpensively by an injection molding process.

[0012] A recess for receiving the second part can be provided on the side of the first part facing the at least one light source. Such a recess can facilitate the positioning of the second part on the first part, especially if the internal dimensions of the recess substantially correspond to the external dimensions of the second part.

[0013] It is possible that the second part of the collimating optics is adhered to the side of the first part facing the at least one light source, in particular by a silicone adhesive or a UV adhesive. Adhering the second part to the first part is also a quite inexpensive manufacturing method.

[0014] For example, for this purpose, at least one receiving part, preferably a plurality of receiving parts, can be arranged on the side of the first part facing the at least one light source, and before the second part is adhered, an adhesive for adhering the second part is introduced into the receiving part, in particular where the at least one receiving part is arranged in the recess. In addition, at least one contact surface, preferably a plurality of contact surfaces, for the second part can be formed on the side of the first part facing the at least one light source, in particular where the at least one contact surface is arranged adjacent to the at least one receiving part in the recess. After the adhesive has been introduced into the at least one receiving part, the second part can be pressed against the at least one contact surface of the first part to firmly bond the parts together. Description of the Drawings

[0015] The present invention will be explained in more detail below with reference to the drawings. Thus:

[0016] Figure 1 A perspective view of the collimating optics of the lighting device according to the present invention is shown;

[0017] Figure 2 Shown Figure 1 An exploded view of the shown collimating optics;

[0018] Figure 3 Shown according to Figure 1 A perspective view of the first part of the collimating optics;

[0019] Figure 4 Shown according to Figure 1 Another perspective view of the first part of the collimating optics. Detailed Description of the Invention

[0020] In the drawings, identical or functionally identical parts are given the same reference signs. For better orientation, a Cartesian coordinate system is drawn in some of the drawings.

[0021] The illustrated embodiment of the lighting device according to the invention in the drawings is designed as a headlight. The lighting device includes a plurality of light sources (not shown), a collimation optics 1, and a secondary optics (not shown).

[0022] The light sources are in the form of light-emitting diodes (LEDs), from which light is emitted during operation of the lighting device. For example, the illustrated embodiment of the lighting device may have a row of three light-emitting diodes spaced apart from one another. These light-emitting diodes can in particular be arranged on a common printed circuit board.

[0023] These light-emitting diodes are arranged adjacent to one another in a first direction X, which corresponds to the horizontal or transverse direction of the motor vehicle when installed in the motor vehicle. In Figure 1 and Figure 4 a second direction Y perpendicular thereto is also shown, which corresponds to the vertical direction when installed in the motor vehicle.

[0024] The collimation optics 1 has a first part 2 and a second part 3 (see Figure 2 ).

[0025] The first part 2 is made of plastic. Three collimation lenses 4 are formed on the first part 2, which are arranged on the side of the first part 2 facing away from the light sources in the assembled state of the lighting device (see Figure 3 ). These collimation lenses 4 are also arranged side by side in the first direction X.

[0026] The second part 3 is made of glass. In the assembled state of the lighting device, the second part 3 is arranged between the first part 2 and the light sources. The second part 3 has the shape of a narrow strip, the longitudinal direction of which is parallel to the first direction X.

[0027] The collimation optics 1 also has three aperture openings 5, which are arranged on the side of the second part 3 facing the light sources (see Figure 1 ). The aperture openings 5 are also arranged adjacent to one another in the first direction X. In each case, one of the aperture openings 5 and one of the collimation lenses 4 are assigned to one of the light sources, such that the light emitted from the light sources successively passes through the assigned aperture openings 5 and the assigned collimation lenses 4.

[0028] It can be provided that the lower edge of one, several or each of the aperture openings 5 is imaged by the optics formed by the collimation optics 1 and the secondary optics of the lighting device as a horizontal cut-off line between light and dark in the external space of the motor vehicle.

[0029] The diaphragm openings 5 are each formed as openings in an opaque layer on the second part 3. The opaque layer can be applied in particular by vapor deposition or coating, whereby the openings can be introduced into the layer by exposure to laser radiation. The opaque layer can in particular be a metal layer.

[0030] The first part 2 of the collimating optical device 1 has, on the side facing the second part 3, a recess 6 for receiving the second part 3. The recess 6 extends into the first part 2 and has an at least partially surrounding edge 7. In the illustrated embodiment, four mutually spaced receiving portions 8 are arranged in the recess 6. In addition, four contact surfaces 9 are provided, which are arranged adjacent to the receiving portions 8 in the recess 6 (see Figure 4 ).

[0031] The first part 2 of the collimating optical device 1 can be manufactured, for example, by an injection molding process. The opaque layer having the diaphragm openings 5 can be applied to the second part 3 before it is joined to the first part 2.

[0032] An adhesive is introduced into the receiving portions 8 to join the two parts 2, 3 together. This can be, for example, a silicone adhesive or a UV adhesive. Then the second part 3 is pressed into the recess 6 of the first part 2 until the second part 3 abuts against the contact surfaces 9. In particular, the internal dimensions of the recess 6 can substantially correspond to the external dimensions of the second part 3, such that the second part 3 abuts against the edge 7 of the recess 6 from the inside.

[0033] After the adhesive has cured, the two parts 2, 3 are firmly joined. When using a UV adhesive, for this purpose, the region where the two parts 2, 3 are joined is exposed to UV light.

[0034] List of reference numerals

[0035] 1 Collimating optical device

[0036] 2 First part of the collimating optical device

[0037] 3 Second part of the collimating optical device

[0038] 4 Collimating lens of the collimating optical device

[0039] 5 Diaphragm opening

[0040] 6 Recess

[0041] 7 Edge of the recess

[0042] 8 Receiving portion in the recess

[0043] 9 Contact surface in the recess

[0044] X First direction or horizontal direction

[0045] The second direction or the vertical direction

Claims

1. A lighting device for a motor vehicle, in particular a headlamp for a motor vehicle, the lighting device comprising: at least one light source; a collimating optical device (1) having at least one collimating lens (4); and a secondary optical device, wherein the lighting device is arranged such that light emitted from the at least one light source successively passes through the collimating optical device (1) and through the secondary optical device, characterized in that the collimating optical device (1) comprises a first part (2) made of plastic and a second part (3) made of glass.

2. The lighting device according to claim 1, wherein The first part (2) comprises the at least one collimating lens (4), and the second part (3) is arranged on a side of the collimating optical device (1) facing the at least one light source.

3. The lighting device according to any one of claims 1 or 2, characterized in that The collimating optical device (1) has at least one aperture opening (5).

4. The lighting device according to claim 3, characterized in that, The at least one aperture opening (5) is arranged on the second part (3) of the collimating optical device (1), in particular on a side of the second part (3) facing the at least one light source.

5. The lighting device according to any one of claims 3 or 4, characterized in that, The at least one aperture opening (5) is formed as an opening in an opaque layer on the second part (3) of the collimating optical device (1), the opaque layer being in particular a metal layer.

6. The lighting device according to any one of claims 1 to 5, characterized in that, The lighting device comprises a plurality of light sources, a plurality of aperture openings (5) and a plurality of collimating lenses (4).

7. The lighting device according to claim 6, characterized in that, In each case, one of the apertures (5) and one of the collimating lenses (4) are associated with one of the light sources such that light emitted from the light source successively passes through the associated aperture opening (5) and the associated collimating lens (4).

8. The lighting device according to any one of claims 6 or 7, characterized in that, The light sources, the aperture openings (5) and the collimating lenses (4) are arranged adjacent to each other in at least one row in a first direction (X), the first direction corresponding to the horizontal direction when the lighting device is installed in the motor vehicle.

9. The lighting device according to claim 8, characterized in that, The second part (3) of the collimating optical device (1) is bar-shaped and has a longitudinal direction parallel to the first direction (X), in particular wherein the second part (3) extends substantially over the entire width of the collimating optical device (1) in the first direction (X).

10. A method of manufacturing a lighting device according to any one of claims 1 to 9, characterized in that, The first part (2) of the collimating optical device (1) is made of plastic, and the second part (3) of the collimating optical device (1) is attached to a side of the first part (2) facing the at least one light source.

11. The method according to claim 10, characterized in that, The first part (2) of the collimating optical device (1) is made of plastic by an injection molding process.

12. The method according to any one of claims 10 or 11, characterized in that, A recess (6) for receiving the second part (3) is provided on a side of the first part (2) facing the at least one light source.

13. The method according to any one of claims 10 to 12, characterized in that, The second part (3) of the collimating optical device (1) is adhered to a side of the first part (2) facing the at least one light source, in particular by a silicone adhesive or a UV adhesive.

14. The method according to claim 13, wherein At least one receiving portion (8), preferably a plurality of receiving portions (8), is arranged on a side of the first part (2) facing the at least one light source, and an adhesive for adhering the second part (3) is introduced into the receiving portion (8) before the second part (3) is adhered, in particular wherein the at least one receiving portion (8) is arranged in the recess (6).

15. The method according to any one of claims 10 to 14, characterized in that, At least one contact surface (9), preferably a plurality of contact surfaces (9), for the second part (3) is formed on the side of the first part (2) facing the at least one light source, in particular, wherein the at least one contact surface (9) is arranged adjacent to the at least one receiving portion (8) in the recess (6).

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