Lighting Device for a Motor Vehicle

A lighting device for a motor vehicle includes one or more first lighting units, each of which is configured to generate a light distribution for a dipped beam function and/or a high beam function, and one or more second lighting units, each of which is configured to generate a light distribution for another lighting function. The first lighting unit(s) and the second lighting unit(s) are all covered by a common outer light panel which is translucent at least in some sections and via which light originating from the first lighting unit(s) and from the second lighting unit(s) exits from the lighting device. Each of the first lighting unit(s) is arranged at a distance from the outer light panel. Each of the second lighting unit(s) is rigidly connected to the outer light panel or is arranged at a distance from the outer light panel.

BACKGROUND AND SUMMARY OF THE INVENTION

The invention relates to a lighting device for a motor vehicle.

The prior art discloses integrating, in a front headlamp of a motor vehicle, further light functions as well as the main light functions (e.g. dip beam and high beam), for example daytime running light, position light or turn signal. The lighting units with the corresponding light functions are generally positioned behind a transparent outer lens, through which the light for the light functions exits from the headlamp.

Especially in the case of a construction in which the outer lens concludes flush with the bumper fascia of the motor vehicle, in the event of a low-speed impact, there should be prevention of movement of or damage to the lighting units within the lighting device as a result of the deformation or movement of the outer lens caused thereby.

It is an object of the invention to create a lighting device for a motor vehicle in which the risk of damage to the lighting units installed therein is minimized in the event of a low-speed impact.

This object is achieved by the lighting device according to the claimed invention.

The lighting device of exemplary embodiments of the invention is intended for a motor vehicle, for example a car and possibly even a truck. Where interactions between the lighting device and components of the motor vehicle are described hereinafter, and especially in the claims, this should always be understood such that the interaction occurs in the case of arrangement or installation of the lighting device in the motor vehicle. The components of the lighting device that interact correspondingly with the motor vehicle or components of the motor vehicle are thus configured such that the interaction is caused in the case of arrangement or installation of the lighting device in the motor vehicle.

The lighting device according to exemplary embodiments of the invention comprises one or more first lighting units that are each set up to create a light distribution for a dip beam function and/or a high beam function. In one variant, only a single first lighting unit is installed in the lighting device, but it is also possible that there are two or more such lighting units for implementation of the dip beam function or high beam function. The first lighting unit (if only one is present) is, or the totality of all first lighting units are, set up to create both a dip beam function and a high beam function. The dip beam function or main beam function means that the lighting device of exemplary embodiments of the invention constitutes a lighting device for the front of the corresponding motor vehicle.

As well as the first lighting unit(s), the lighting device of exemplary embodiments of the invention includes one or more second lighting units that are each set up to create a light distribution for a light function other than the dip beam function and the main beam function. Preferably, at least some of the second lighting units and possibly even all second lighting units are set up to create a light distribution for a signal light function.

The first lighting unit or the first lighting units and the second lighting unit or the second lighting units in the lighting device of exemplary embodiments of the invention are covered by a common outer lens which is transparent at least in sections and through which light coming from the first lighting unit or the first lighting units and the second lighting unit or the second lighting units exits from the lighting device. Here and hereinafter, the term “light” refers to optical radiation in a wavelength range visible to the human eye. Moreover, here and hereinafter, the term “transparent” is understood to mean that there is a transmittance of greater than zero and especially of 50% or more and preferably of 90% or more for light.

In the lighting device of exemplary embodiments of the invention, the first lighting unit or the first lighting units are each spaced apart from the outer lens. In addition, the second lighting unit or the second lighting units are each (mechanically) rigidly connected to the outer lens or spaced apart from the outer lens. It may be possible here for some of the second lighting units each to be rigidly connected to the outer lens, while some other second lighting units are each spaced apart from the outer lens. Preferably, at least some of the second lighting units are rigidly connected to the outer lens, and it is optionally also possible for all these second lighting units to be both rigidly and directly (i.e. without further bridging components) connected to the outer lens. The rigid (mechanical) connection may be different depending on the configuration. In particular, this may be a cohesive and/or force-fitting and/or form-fitting connection.

The lighting device of exemplary embodiments of the invention has the advantage that damage to the first lighting unit(s) in the event of a low-speed impact (e.g. a minor parking accident) is avoided because they are spaced apart from the outer lens. By contrast, damage to the second lighting unit(s) in the event of such an impact is counteracted in that, because of the rigid connection to the outer lens, they move therewith, or in that they are spaced apart from the outer lens. The rigid connection of the second lighting units to the outer lens also achieves a compact construction of the lighting device.

In a particularly preferred variant of the lighting device of the invention, the second lighting unit or the second lighting units are set up to create a light distribution for a daytime running light and/or for a position light and/or for a turn signal and/or for illumination of an area along the outer lens and/or for contour lighting along one edge of the outer lens. The area lighting may be used, for example, in a lighting effect in order to generate a pleasing dynamic distribution of light, for example as welcome light when the motor vehicle is unlocked.

In a further configuration of the lighting device of the invention, at least a first lighting unit and preferably each first lighting unit is a lighting module comprising a housing in which there is disposed a light emitter for creation of the light distribution for the dip beam function and/or the high beam function. The light emitter may comprise, for example, one or more LEDs and/or laser diodes.

In a further preferred variant of the invention, the housing of the first lighting unit configured as lighting module is connected to the outer lens via a flexible connector. The flexible connector is preferably a sleeve with two opposite open ends, with one end of the sleeve secured to the housing of the lighting module, preferably around a light exit opening, and the other end of the sleeve secured to the outer lens.

In order to prevent the penetration of soil or other particles into the first lighting unit configured as lighting module, the sleeve, in a preferred embodiment, is formed from material impervious to dust and is secured with sealing by its ends to the housing of the first lighting unit and to the outer lens.

In a further preferred embodiment, at least one second lighting unit and preferably each second lighting unit is a lighting module comprising a housing in which there is disposed a light emitter for creating the light distribution for the light function other than the dip beam function and high beam function. The light emitter may comprise, for example, one or more LEDs and/or laser diodes.

In a particularly preferred embodiment, the housing of the second lighting unit configured as a lighting module is (mechanically) rigidly and preferably directly (i.e. without bridging components) connected to the outer lens, which ensures simple assembly of the lighting device. The rigid (mechanical) connection may be different depending on the configuration. In particular, this may be a cohesive and/or force-fitting and/or form-fitting connection.

In a further configuration, at least one second lighting unit comprises a surface light guide. Depending on the configuration, the surface light guide may be rigidly connected to the outer lens or else optionally be spaced apart therefrom.

In a further preferred configuration, the lighting device of the invention, as well as the first and second lighting units, also comprises one or more radiation units for emission of radiation other than light, for example in the form of one or more radar devices and/or lidar devices. This variant allows functional units that do not have a lighting function but assume other functions (especially distance measurement) to be integrated into the lighting device of exemplary embodiments of the invention.

In a preferred variant of the embodiment just described, at least one radiation unit and optionally each radiation unit is connected rigidly and preferably directly (i.e. without bridging components) to the outer lens, which ensures a compact construction of the lighting device. The rigid (mechanical) connection may be different according to the configuration. In particular, this may be a cohesive and/or force-fitting and/or form-fitting connection.

In a further preferred embodiment, the outer lens of the lighting device is formed from plastic, which may comprise polyurethane for example. This reduces the weight of the outer lens. The plastic is preferably a multicomponent injection molding, which is easy to produce. In addition, by way of a multicomponent injection molding, it is possible to form transparent and opaque regions in the outer lens in a simple manner.

In a further preferred variant, an inner surface of the lighting device which is visible through the outer lens has an absorptivity of 50% or more, especially of 90% or more, for light. In other words, the visible inner region of the outer lens is configured to look dark, which achieves a pleasing cold appearance of the lighting device in the form of a continuous dark area.

In a further preferred embodiment, the outer lens of the lighting device of the invention, on installation in the motor vehicle, has an extent in transverse direction of the motor vehicle that extends from one edge of the motor vehicle to essentially the center thereof. This achieves a pleasing design in which the configuration of a kidney on the front of the motor vehicle is dispensed with entirely.

As well as the lighting device of exemplary embodiments of the invention, the invention relates to a motor vehicle comprising one or more of the lighting devices of exemplary embodiments of the invention.

A working example of the invention is described in detail hereinafter with reference to the appended figures.

DETAILED DESCRIPTION OF THE DRAWINGS

There follows a description of an embodiment of the invention with reference to a motor vehicle lighting device in the form of a left-hand front headlamp. This headlamp is shown schematically inFIG.1in a top view from the front onto the front of the motor vehicle, and identified by reference numeral1. The front headlamp comprises an outer lens2, which is a multicomponent injection molding, as described in detail further down. A majority of the outer lens is transparent, in order to allow light to exit from the lighting device. Within the lighting device there are a plurality of lighting units or lighting modules, which are shown merely schematically inFIG.1by illustration of their outlines.

In the right-hand region of the outer lens2is a main light module3, which is intended to create the dip beam and the high beam of the motor vehicle and is a first lighting unit in the context of the claims. The main light module contains two optical units3band3cthat are indicated merely schematically, with which dip beam and high beam are generated by way of light from light sources behind the optical units (not shown).

Above the main light module3, behind the outer lens2, are disposed two signal lighting units or signal lighting modules4,4′, which are second lighting units in the context of the claims. The signal lighting units are shown merely schematically inFIG.1as bars and serve collectively to create daytime running light while running in daylight, and to create position light while running in darkness. When generating daytime running light and position light, the signal lighting units emit white light. In addition, the signal lighting unit4also assumes the function of the turn signal. This means that the activation of the turn signal actuates flashing of the signal lighting unit4in a yellow color, such that, during the flashing, the function of the daytime running light or position light of this signal unit is deactivated. After the flashing has ended, the signal lighting unit shines again in the white color of the daytime running light or position light. In the region of the outer lens2, behind which there are the main light module3and the signal lighting units4,4′, the outer lens is completely transparent, in order thereby to assure the creation of the dip beam or high beam and of the signal lighting functions efficiently with low energy losses.

To the left alongside the main light module3and the signal lighting units4,4′ is an area lighting device5, of which merely the outline is indicated by a dotted line, and which constitutes a (further) second lighting unit in the context of the claims. The area lighting device5is disposed behind a stripe pattern8(seeFIG.2toFIG.4) of the outer lens2and, on activation, creates an area of light within its outline, such that stripes of light become visible on the outer lens because of the stripe pattern8. There may optionally also be a different pattern than a stripe pattern or else no pattern at all on the outer lens in the region of the area lighting device5.

The area lighting device5is preferably used for light effects. The area lighting device5can be actuated here such that it is also possible to illuminate only subareas within its outline and hence to generate dynamic light movements. This can be utilized, for example, in the case of a welcome scenario for the driver when unlocking the motor vehicle. In the case of this welcome scenario, a pleasing dynamic light image is generated by way of the area lighting device5in both front headlamps, optionally in conjunction with the position light, and the driver is greeted thereby.

In addition, the front headlamp1comprises what is called a contour lighting device6, which is shown merely schematically by a dotted line running around the edge of the outer lens. The contour lighting is implemented by a circumferential light guide, as described in detail further down. The activation of the contour lighting achieves a pleasing appearance of the front of the motor vehicle.

The front headlamp1further comprises a radar7disposed on the left-hand side of the outer lens2beneath and alongside the area lighting device5. Only the outline of the radar is indicated inFIG.1. The radar emits radar beams and detects the radar echoes received, in order thereby to measure distances from objects. The radar is used in driver assistance functions, for example a pedestrian warning or active cruise control. The stripe pattern8in front of the area lighting device5also runs across the radar7. However, the stripe pattern is transparent to the wavelength of the radar radiation, and so the intensity of the radar radiation emitted is not impaired by the stripe pattern.

FIG.1also indicates three dashed-and-dotted lines L1, L2and L3, which indicate section lines, with the corresponding sections along these lines shown inFIG.2toFIG.5. The sections are along the corresponding line in horizontal direction, andFIG.2toFIG.5show the viewing direction of the respective sections in vertical direction from the top downward.

In the embodiment of the front headlamp1shown here, the inner surface of the headlamp, which is visible through the outer lens2, has a light-absorbing or dark configuration. In this way, a viewer perceives an essentially dark area in the region of the outer lens in the cold appearance of the headlamp (i.e. with the headlamp switched off). In addition, the outer lens2extends from the left-hand edge or fender of the motor vehicle almost up to the center thereof in its transverse direction. In this way, the headlamps installed on the two sides achieve a pleasing appearance of a continuous area on the front of the motor vehicle. This dispenses with the integration of a kidney on the front of the motor vehicle.

Furthermore, the outer lens2concludes flush with the bumper fascia10(seeFIG.2toFIG.4) on the front of the motor vehicle, which achieves a visually pleasing design. However, there is the problem that a low-speed impact on the front of the motor vehicle (as, for example, in the case of a minor parking accident) will result in a direct force acting on the outer lens2, since there is no curved bumper region below the front headlamp. This force may lead to displacement or damage to the lighting units installed in the front headlamp. In order to avoid this problem, the lighting units are arranged behind the outer lens in a specific manner, as elucidated in detail hereinafter with reference toFIG.2toFIG.5.

FIG.2shows a section along line L1inFIG.1, meaning that the section runs through the contour lighting device6, the area lighting device5and the upper signal lighting unit4. The outer lens2is a component which is composed of multiple plastic components and has been manufactured by multicomponent injection molding and comprises an outer transparent component or layer2a, a transparent film2bapplied atop layer2a, and a further component in the form of an opaque layer2cthat has been provided solely in subareas atop film2band serves to secure the signal lighting units4,4′, the area lighting device5, the contour lighting device6and the radar7. It is also apparent fromFIG.2that the outer lens2concludes flush with the bumper fascia, identified by reference numeral10.

In the region of the outer lens through which the area lighting device5emits light, the stripe pattern8already mentioned above has been printed onto the film2b, and also printed on in this region is a decoration9that becomes visible when the area lighting device5is switched on. In the embodiment described here, the decoration is the emblem or logo of the vehicle manufacturer. By contrast with the area lighting device5, there is neither a stripe pattern nor a decoration in the regions of the outer lens behind which the main light module3, the signal lighting units4,4′ and the contour lighting device6are present.

According toFIG.2, the signal lighting unit4comprises a housing4awhich is open toward the outer lens2, in which there is a light emitter in the form of a printed circuit board4bequipped with LEDs and diffusing optics4cin front of the latter. The LEDs may give off different colors, such that both an indicating function (lit in yellow color) and a daytime running light function or position light function (lit in white color) are achieved. The signal lighting unit4and also the signal lighting unit4′ which is apparent fromFIG.1, and which is of identical construction to the signal lighting unit4, are rigidly connected to the outer lens2via the housing4a, with the housing4abonded to the layer2cin the working example described here.

The area lighting device5is of similar construction to the signal lighting unit4. This means that it comprises a housing5awhich is open toward the outer lens2and comprises a light emitter in the form of a printed circuit board5bequipped with LEDs and diffusing optics5cin front of the latter. This area lighting device5is likewise rigidly connected to the outer lens2in that the housing5ais stuck to the layer2cof the outer lens2.

Also apparent fromFIG.2are the sections through the circumferential contour lighting device6. The contour lighting device6comprises a housing6awhich is open with respect to the outer lens and runs around the edge of the outer lens, in which there is a light guide6b. The light guide is fed with light via a light source at one end (not apparent from the figures). This light is outcoupled therefrom via an outcoupling structure on the side of the light guide6badjacent to the housing6a, which gives rise to circumferential contour light. The inside of the housing6ahas a reflective configuration, which increases the brightness of the contour lighting. In analogy to the signal lighting units4,4′ and the area lighting device5, the contour lighting device6is also rigidly connected to the outer lens2in that the housing6ais stuck to the layer2cof the outer lens. The rigid securing of the lighting units4,4′,5and6to the outer lens2firstly achieves a compact construction of the headlamp and secondly prevents damage to these lighting units via a force acting on the outer lens, since the lighting units move together with the outer lens.

FIG.3shows a section along line L2inFIG.1. This line runs through the contour lighting device6, the area lighting device5and the main light module3, except that the interior of the main light module is not shown in section. As can be seen, the main light module3comprises a housing3awith an open front side or light exit opening3d, via which the light generated in the main light module exits via the optical units3band3c. Because of the size and depth of the main light module3, it is impracticable to rigidly connect this module to the outer lens2. Furthermore, the main light module contains an illumination width regulator for adjusting the dipped beam to the loading of the motor vehicle, and so, for that reason too, rigid securing of the main light module to the outer lens is impossible.

In order nevertheless to prevent movement of or damage to the main light module3as a result of the movement of the outer lens2in the event of an impact, the main light module3is positioned at a distance from the outer lens2. In order to prevent the penetration of soil or other particles into the interior of the housing3avia the light exit opening3d, a shell or sealing sleeve11is provided between the main light module3and outer lens2. The end of the sealing sleeve adjacent to the housing3aof the main light module3runs around the circumference of the light exit opening3dand is secured with sealing to the housing, as described further down with reference toFIG.5. The end of the sealing sleeve adjacent to the outer lens2is likewise mounted with sealing on layer2cof the outer lens, as likewise still to be described in detail with reference toFIG.5.

FIG.4shows a section along line L3inFIG.1, where this line runs through the contour lighting device6, the radar7, the area lighting device5and the main light module3. As can be seen fromFIG.4, the radar7comprises an emitting and receiving unit7afor emitting radar rays and receiving the corresponding radar echoes. In analogy with the lighting units4,4′,5and6, the radar7is also rigidly connected to the outer lens2. For this purpose, a funnel-shaped holder7bmounted on the emitting and receiving unit7ais stuck to layer2cof the outer lens. This rigid securing counteracts damage to the radar resulting from movement of the outer lens2in the event of an impact, since the radar moves with the outer lens.

FIG.5shows a detail view of the main light module3fromFIG.5and the securing thereof on the outer lens2, with omission of the contour lighting device6for reasons of clarity. As can be seen, the sealing sleeve11that connects the main light module3to the opaque layer2cof the outer lens2consists of a plastic composed of two different components. The edges11aof the sealing sleeve11consist of a mixture of polycarbonate and ABS plastic (ABS=acrylonitrile-butadiene-styrene). By contrast, the middle section11bof the sealing sleeve is formed from TPE plastic (TPE=thermoplastic elastomer). The TPE plastic ensures the flexibility of the sealing sleeve11. The edge of the sealing sleeve11adjacent to the outer lens2is bonded by way of polyurethane adhesive14to layer2cof the outer lens. By contrast, the opposite edge of the sealing sleeve11is mounted on the main light module3by way of a total of eight metal clips13, with two of these clips apparent inFIG.5. The main light module comprises a circumferential projection3ewhich presses against a projection11cof the sealing sleeve via a sealing element12made of EPDM material (EPDM=ethylene-propylene-diene rubber). The compression force is generated by way of the metal clips13. Such a construction gives very good protection of the components of the main light module3that are exposed via the light exit opening3dagainst the penetration of dust or other particles.

Rather than a sealing sleeve, it is also possible to use a different form of sealing. It is likewise possible for the sealing sleeve to consist of other materials or to be secured to the main light module or outer lens in another way. For example, rather than securing by way of clips, it is also possible to utilize securing by way of adhesive bonding, clamping and the like.

The above-described embodiment of the invention has a number of advantages. In particular, a motor vehicle lighting device is provided in the form of a front headlamp, the components of which are well protected against damage in the event of a low-speed impact. This is brought about firstly by the spacing of the main light module from the outer lens and secondly by a rigid mechanical connection of further lighting units to the outer lens. In this way, movements or shifts of the outer lens in the event of a low-force impact are prevented from leading immediately to damage to the lighting units installed in the front headlamp. Furthermore, the positioning of lighting units directly on the outer lens ensures a compact construction of the lighting device. Nevertheless, it is also possible that one or more of the lighting units connected rigidly to the outer lens in the embodiment described above are spaced apart therefrom.

LIST OF REFERENCE NUMERALS

1front headlamp (lighting device)2outer lens2atransparent component2bfilm (for decoration and/or opacity)2copaque component3first lighting unit (main light module)3ahousing of the main light module3b,3coptical units3dlight exit opening in the main light module3eprojection in the main light module4,4′ signal lighting units (two lighting units)4ahousing of the signal lighting unit4bprinted circuit board with direct-emitting LEDs4cdiffusing optics5area lighting device (second lighting unit)5ahousing of the area lighting device5bprinted circuit board with direct-emitting LEDs5cdiffusing optics6contour lighting device6ahousing of the contour lighting device6blight guide of the contour lighting device7radar (emission unit)7atransmitting and receiving unit7bholder8stripe pattern9decorative print10bumper fascia11sealing sleeve (flexible connector)11a,11bmaterial components of the sealing sleeve11cprojection on the sealing sleeve12sealing element13metal clips14adhesive