Lighting device for vehicles

Abstract

Lighting device for vehicles with a light source (5) and with a light guide (1, 2), - which has a light coupling surface (7) on one side facing the light source (5) for coupling in light emitted from the light source (5), - which has opposing surfaces (8, 9) for total reflection of the coupled light, - which has a light output surface (8) for illuminating a predetermined light signature, - the coupling element has a feature for directing the coupled light to the light coupling surface according to the specified light signature, that the optical fiber (1, 2) consists at least partially of a flexible material, such that the shape of the optical fiber (1, 2) is variable in its direction of extension (E1, E2), that the optical fiber (1, 2) has a flexible optical fiber section (11, 21) extending in a region of the optical fiber (1, 2) facing the light source (5), and that the optical fiber (1, 2) has a rigid optical fiber section (12, 22) extending in a region of the optical fiber (1, 2) facing away from the light source (5), characterized in that the flexible optical fiber section (11, 21) and the rigid optical fiber section (12, 22) are made of the same material, wherein the rigid optical fiber section (12, 22) has greater dimensional stability than the flexible optical fiber section (11, 21), and - that the rigid light guide section (12, 22) with its light output surface (8, 25) is integrally formed on the inside of a transparent light disk (6) of the housing or - that the rigid light guide section (12, 22) with its free end (14, 26) lies directly against a circumferential mounting edge (15) of the light disk (6).

Description

[0001] The invention relates to a lighting device for vehicles according to the preamble of claim 1.

[0002] From EP 2 354 637 A2, a lighting device for vehicles is known, which essentially consists of a planar light guide and a series of light sources. The planar light guide has two opposing surfaces at which the coupled light is totally reflected. On one side facing the light source, the planar light guide has a light coupling surface through which the light emitted by the light source is coupled into the light guide. The planar light guide is S-shaped, with a front surface of the light guide forming a light coupling surface. A rear surface of the light guide has coupling elements that direct the coupled light towards the front surface, so that a homogeneous light emission occurs at the front surface in the manner of a "light curtain". This creates a planar light signature, which can be used, for example, as a taillight function.A disadvantage of the known lighting device is that, due to its large surface area, precise adaptation to a housing of the lighting device or to a crystal-clear light disc covering the housing is required in order to enable the largest possible illumination area.

[0003] From EP 0 900 694 A2, a lighting device for vehicles is known, comprising a light source and a light guide, which is designed as a rigid, circular light guide. The rigid light guide is held in a trough-shaped recess of a housing of the lighting device by a snap-fit ​​connection.

[0004] From DE 100 40 302 A1, a lighting device for vehicles is known, comprising a light source and a light guide. The light guide has a flexible section and a rigid section, the two sections being connected to each other via a plug connection.

[0005] From DE 10 2011 015 161 A1, a lighting device for vehicles with a light source and a light guide is known, wherein the light guide consists of a rigid light guide section and a flexible light guide section. The rigid light guide section is made of a glass material. The flexible light guide section is connected to the rigid light guide section as a separate component via a socket or via an optical element. The rigid light guide section is axially displaceable by means of clamping elements that engage opposite ends. A disadvantage of this mounting is that it disrupts the light signature of the light guide and is visible to an observer from the outside.

[0006] The object of the present invention is therefore to further develop a lighting device for vehicles in such a way that a predetermined light signature can be provided with minimal assembly effort, wherein the light signature can in particular also be provided in narrow installation spaces of a housing of the lighting device.

[0007] To solve this problem, the invention has the features of claim 1.

[0008] The particular advantage of the invention lies in the fact that the assembly effort for the light guide can be significantly reduced. Because the light guide is at least partially made of a flexible material, tolerance differences in other components can be compensated for, and in particular, the light guide can extend into hard-to-reach or confined areas of installation spaces.

[0009] According to the invention, the light guide comprises a flexible light guide section arranged in a region facing the light source and a rigid light guide section arranged in a region facing away from the light source. The flexible light guide section can, for example, serve as a flexible light feed section, while the rigid light guide section essentially comprises the light output surface and generates the desired light signature. The flexible light guide section allows for increased flexibility in positioning the light source within the housing of the lighting device.

[0010] According to a first embodiment of the invention, the rigid light guide section is directly integrally formed on the inner side of a transparent light disk within the housing of the lighting device. The flexible light guide section, which is integrally connected to the rigid light guide section, serves as the light feed between the light source and the rigid light guide section. Advantageously, this embodiment enables an extended light signature that can reach far into a side area of ​​the housing.

[0011] According to a second embodiment of the invention, a free end of the rigid light guide section rests directly against a circumferential mounting edge of the lens. If the lighting device is a two-part device, for example, designed as a taillight, where one part is fixed and the other part is movable as part of a tailgate, the interruption of the signature running from the first part to the second part of the lighting device can be significantly reduced. This reduces a dead zone that arises due to the distance between the housing edges or lens edges of the two parts of the lighting device.

[0012] According to a preferred embodiment of the invention, the rigid light guide section is arranged in a shallow area of ​​the lighting device housing, and the flexible light guide section is arranged in a deep area of ​​the housing. Advantageously, this allows for a longer light signature than with a purely rigid light guide. The light output losses of the light guide are relatively low, since the flexible light guide section can be bent almost automatically during assembly without forming sharp kinks.

[0013] An embodiment of the invention is explained in more detail below with reference to the drawings.

[0014] They show: Fig. 1. A perspective front view of a lighting device with a planar light guide and with a rod-shaped light guide. Fig. 2 a perspective rear view of the lighting device and Fig. 3 A perspective rear view of the planar and rod-shaped light guide.

[0015] A lighting device according to the invention for vehicles can be used as a signal light in the front or rear area of ​​a motor vehicle. For example, the lighting device can be used to generate a daytime running light, tail light, or turn signal function.

[0016] According to an exemplary embodiment of the invention according to the Fig. The lighting device, as described in sections 1 to 3, essentially comprises a first rod-shaped light guide 1 and a second planar light guide 2, each of which is assigned a number of light sources 5 at a first end 3 or 4, respectively. The light sources 5 can be designed as LED light sources or as laser light sources.

[0017] The rod-shaped light guide 1 and the planar light guide 2 extend within a pot-shaped housing (not shown), the opening of which is located at the front in the main emission direction H and is covered by a transparent light disc 6.

[0018] The rod-shaped light guide 1 can be used, for example, to generate a flashing light function and the planar light guide 2 to generate a tail light function.

[0019] Additional lighting units can be integrated within the housing to generate further lighting functions.

[0020] The rod-shaped optical fiber 1 has a rectangular cross-section. An end face 3 of the rod-shaped optical fiber 1 is designed as a light coupling surface 7, into which light emitted by the individual light source 5 is coupled. Along the direction E1 of the rod-shaped optical fiber 1, opposite surfaces 8 and 9 adjoin the light coupling surface 7, at which the coupled light is totally reflected along the direction E1. The opposite surfaces 8 and 9 are connected to each other by narrow sides 10 extending along the direction E1.

[0021] The rod-shaped optical fiber 1 consists of a flexible optical fiber section 11, which extends in a region of the optical fiber 1 facing the light source 5. Furthermore, the rod-shaped optical fiber 1 has a rigid optical fiber section 12 in a region facing away from the light source 5.

[0022] The rigid optical fiber section 12 has a number of coupling elements on the rear surface 9 in the main emission direction H, which serve to deflect the coupled light towards the front surface 8, which serves as the light coupling surface. For clarity, the rear surface 9 of the rigid optical fiber section 12 is shown in Fig. 2 shown hatched.

[0023] The rigid light guide section 12 is bonded to the light disk 6, preferably by injection molding onto a disk surface 6' of the light disk 6. The front surface 8, i.e., the light output surface of the rigid light guide section 12, rests directly against an inner surface of the disk surface 6' of the light disk 6. Advantageously, this eliminates any air gap between the rigid light guide section 12 and the light disk 6. Furthermore, this arrangement secures the rod-shaped light guide 1 to the light disk 6. Additional fastening means for securing the rod-shaped light guide 1 within the housing are not required.

[0024] The flexible optical fiber section 11 is designed to pivot about an axis passing through the opposite narrow sides 10 of the rod-shaped optical fiber 1. The material properties of the flexible optical fiber section 11 are such that a limited pivotability of the flexible optical fiber section 11 about an axis perpendicular to the surfaces 8, 9 is possible. In the present embodiment, the flexible optical fiber section 11 is designed to pivot essentially about a vertical axis, due to its material properties. The flexible optical fiber section 11 thus exhibits no or only slight pivotability with respect to a horizontal axis, but relatively large pivotability about a vertical axis. This directional deformation capability allows the first end 3 of the rod-shaped optical fiber 1 to be pivoted.the flexible light guide section 11 is brought close to the light source 5 in such a way that optimal light coupling is ensured and tolerance deviations are compensated for.

[0025] Additional fastening means may be provided to fix the flexible light guide section 11 in the mounting position. The rigid light guide section 12 abuts with its free end 14, which forms a second end of the rod-shaped light guide 1, directly against a mounting edge 15 of the light lens 6.

[0026] The mounting edge 15 is arranged around the perimeter of the light lens 6 and is connected to the housing of the lighting device (not shown) in a known manner via a fluidized bed. The second end 14 of the rod-shaped light guide 1 rests directly against the mounting edge 15 with its end face. Preferably, the second end 14 is injection-molded onto a large surface 6' of the light lens 6', similar to the front surfaces 8.

[0027] The flexible light guide section 11 consists of segments 16, 17, and 18 arranged one behind the other in the direction of extension E1 and exhibiting different degrees of flexibility. Segment 16, which immediately adjoins the rigid light guide section 12, has a lower degree of flexibility than segment 17 and / or segment 18, which adjoin the rigid light guide section 12 at its end face on the opposite side. In this way, the flexibility can be continuously increased towards the first end 3, which simplifies assembly. Preferably, segment 18 facing the light source 5 is locked in the assembly position by retaining means (not shown), so that a clear relative position to the light source 5 exists.

[0028] The rod-shaped light guide 1 is S-shaped, with the rigid light guide section 12, with its light output surface 9, directly abutting the disk surface 6' of the light disk 6, and the flexible light guide section 11 being spaced apart from the light disk 6. The light source 5 is located in a region of the housing with a relatively large installation depth b1, while the installation depth b2 at the second end 14 of the rod-shaped light guide 1 is relatively small. The installation depth b1, b2 is defined as the distance from the light disk 6 to a base of the housing opposite the light disk 6.

[0029] The planar optical fiber 2 has a flexible optical fiber section 21 and a rigid optical fiber section 22 integrally connected to it, which is in Fig.2 is marked with hatching for simplified illustration. The rigid light guide section 12 is injection-molded onto the inside of the disk surface 6' of the light disk 6 – like the rigid light guide section 12 of the rod-shaped light guide 1. The flexible light guide section 21 extends at a distance from the disk surface 6' in an area of ​​greater depth b3, in which several light sources 5 are arranged side by side. An elongated light coupling surface 23 of the planar light guide 2 is assigned to the light sources 5. Opposite surfaces 24, 25 adjoin in the direction of extension E2, at which the coupled light is totally reflected towards a second end 26 of the planar light guide 2. In the rigid light guide section 22, output coupling elements are arranged on the rear surface 25, by means of which coupled light striking them is deflected towards the front surface 25 for output at the same.The front surface 25 thus serves as a light extraction surface. Surfaces 24 and 25 are connected to each other by narrow sides 27.

[0030] The front surface 25 of the planar light guide 2 lies directly against the disk surface 6' of the light disk 6. The rigid light guide section 22 lies with its free end 26 directly against a circumferential mounting edge 15 of the light disk 6.

[0031] The flexible light guide section 21 can consist of segments 28, 29 which have different dimensional stability.

[0032] The flat light guide 2 enables flat illumination, while the rod-shaped light guide 1 enables linear illumination or light signature.

[0033] The rigid optical fiber section 12, 22 of the optical fiber 1, 2 consists of a different material than the flexible optical fiber section 11, 21 of the same, wherein the flexible optical fiber section 11, 21 is molded or injection-molded onto the rigid optical fiber section 12, 22.

[0034] According to an alternative embodiment not shown, the flexible light guide section 11, 21 and the rigid light guide section 12, 22 can also be made of the same material, wherein the rigid light guide section 12, 22 has greater dimensional stability than the flexible light guide section 11, 21.

[0035] The flexible light guide section 11, 21 is preferably made of a silicone material.

[0036] In an alternative embodiment (not shown), the entire light guide can also be designed as a flexible light guide, made, for example, of silicone. The light guide can then be fixed to the housing or a mounting frame using suitable fasteners.

[0037] According to an alternative embodiment not shown, the rigid light guide section 12, 22 can also be attached only to the disk surface 6' of the light disk 6 without being materially bonded to it.

[0038] The light disc 6 consists of a crystal-clear transparent plastic material.

[0039] The light guides 1, 2, consist of a crystal-clear, transparent plastic material. Reference symbol list 1 rod-shaped light guide 2-plane optical fiber 3, 4 End 5 light sources 6.6' Light disc 7 Light coupling area 8, 9 areas 10 narrow pages 11, 12 Fiber optic section 13 Inside of light lens 14 End 15 Mounting edge 16, 17, 18, 28, 29 segments 21 22 Rigid fiber optic section 23 Light coupling area 24, 25 areas H Main radiation direction E1, E2 Direction of extension b1, b2, b3 installation depth

Claims

[1] Lighting device for vehicles with a light source (5) and with a light guide (1, 2), - which has a light coupling surface (7) on one side facing the light source (5) for coupling in light emitted from the light source (5), - which has opposing surfaces (8, 9) for total reflection of the coupled light, - which has a light output surface (8) for illuminating a predetermined light signature, - the coupling element has a feature for directing the coupled light to the light coupling surface according to the specified light signature, that the optical fiber (1, 2) consists at least partially of a flexible material, such that the shape of the optical fiber (1, 2) in its direction of extension (E1, E2) is changeable, that the optical fiber (1, 2) has a flexible optical fiber section (11, 21) which extends in a region of the optical fiber (1, 2) facing the light source (5), and that the optical fiber (1, 2) has a rigid optical fiber section (12, 22) which extends in a region of the optical fiber (1, 2) facing away from the light source (5), characterized by , that the flexible optical fiber section (11, 21) and the rigid optical fiber section (12, 22) are made of the same material, wherein the rigid optical fiber section (12, 22) has greater dimensional stability than the flexible optical fiber section (11, 21), and - that the rigid light guide section (12, 22) with its light output surface (8, 25) is integrally formed on the inside of a transparent light disk (6) of the housing or - that the rigid light guide section (12, 22) with its free end (14, 26) lies directly against a circumferential mounting edge (15) of the light disk (6). [2] Lighting device according to claim 1, characterized by , that the rigid light guide section (12, 22) has on one side the light output area (8, 24) and on an opposite side the output coupling elements for deflecting the coupled light in the direction of the light output area (8, 24). [3] Lighting device according to claim 1 or 2, characterized by , that the rigid light guide section (12, 22) is located in a shallow depth area (b2) of a housing of the lighting device and that the flexible light guide section (11, 21) is located in a deep depth area (b1, b3) of the housing. [4] Lighting device according to any one of claims 1 to 3, characterized by , that the flexible light guide section (11, 21) is made of a silicone material. [5] Lighting device according to any one of claims 1 to 4, characterized by , that the flexible optical fiber section (11, 21) has different degrees of flexibility in the extension direction (E1, E2) of the same consecutively arranged segments (16, 17, 18; 28, 29). [6] Lighting device according to any one of claims 1 to 5, characterized by , that the optical fiber is designed as a rod-shaped optical fiber (1) or as a planar optical fiber (2).

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