FR3076598A1 - MULTIFUNCTION LIGHTING DEVICE WITH ELECTRONIC CARD WITH PHOTON SOURCES ASSOCIATED WITH A LIGHT GUIDE, FOR A VEHICLE - Google Patents

Abstract

A lighting device (DE) equips a vehicle comprising a license plate (PI), and comprises an electronic card (CE), on which photon sources (SP) are installed, and at least one light guide ( GL), comprising at least two photon-guiding portions (P1-P5) participating in license plate illumination function (PI) and photometric function to exit faces (FS1-FS5) having normals of different directions, one of these output faces (FS1) being traversed by photons guided to illuminate the registration plate (PI).

Description

The invention relates to lighting devices which are fitted to vehicles comprising a license plate to be illuminated.

Here, the term "lighting device" means a light device capable of ensuring at least two photometric lighting or signaling functions regulated for a vehicle. It will be noted that such a lighting device can possibly be housed in a cavity delimited by a housing and a protective glass of a vehicle optical unit, such as for example a rear light.

In certain vehicles, generally of the automobile type, rear light units (or lights) are used providing a photometric function whose light signature is particular. This is for example the case of the position light or stop light function. So that this light signature is clearly visible and well separated from the other photometric functions of the rear optical unit (or light), it is allocated a large surface in the latter. There is then no longer enough space in these rear light units (or lights) to perform other additional photometric functions, such as for example the reversing light function or the fog light function. In addition, there are also regulatory constraints which oblige the brake light to be moved at least 100 mm from the fog light.

To avoid enlarging the lights, which could in particular affect the style of the vehicle, one is forced to deport certain additional photometric functions to the bumper or rear bumper of the vehicle, since they generally do not participate in the style of the vehicle. This is the case, for example, with the reversing light, fog light and reflector functions, which are restrictive in terms of installation. It is therefore desirable to make these remote photometric additional functions as small and as discreet as possible. However, when the architectural constraints are severe, it may be difficult, if not impossible, to install these additional photometric functions in the bumper or rear bumper, in particular when they use bulky photon sources, such as for example lamps, especially for reasons of cost. In addition to their intrinsic dimensions, the lamps require a large volume around them because of thermal and photometric problems. The invention therefore aims in particular to improve the situation.

To this end, it notably proposes a lighting device, on the one hand, intended to equip a vehicle comprising a license plate, and, on the other hand, comprising an electronic card, on which photon sources are installed, and at least one light guide, comprising a rear end supplied with photons by the photon sources and a front end delivering photons guided from the rear end.

This lighting device is characterized in that its light guide comprises at least two parts guiding photons participating in the lighting function of the license plate and photometric function up to exit faces having normal of different directions, one of these exit faces being traversed by guided photons in order to illuminate the license plate.

Thanks to the invention, the lighting device is multifunction, fully integrated, and its electronic card is shared to support the photon sources and their control means, which makes it possible to have only one electric beam of power supply and control for several photometric functions.

The lighting device according to the invention may include other characteristics which can be taken separately or in combination, and in particular: - the rear faces of the rear end may have the same inclination; - the exit faces can have normals making an angle of 90 °; - the rear faces of the rear end may be entry faces through which the photons penetrate. As a variant, the rear faces of the rear end may be faces reflecting in the photon light guide coming from an entry face of the rear end through which the photons penetrate; - its light guide may include at least one other part guiding photons participating in another photometric function to another exit face having a normal having a normal different from that of the exit face which is crossed by guided photons illuminating the license plate; - each photometric function can be chosen from a reversing light function, a fog light function, a stop light function, a position light function, and a direction change indicator function; - its light guide can be flat. The invention also provides an optical unit, intended to equip a vehicle comprising a license plate, and comprising a housing and a protective glass together delimiting a cavity housing a lighting device of the type presented above. The invention also provides a vehicle, possibly of the automobile type, and comprising a registration plate and at least one lighting device of the type presented above and / or at least one optical unit of the type presented here. -before. Other characteristics and advantages of the invention will appear on examining the detailed description below, and the appended drawings, in which: - Figure 1 schematically illustrates, in a perspective view, an example of an optical unit of vehicle comprising a first embodiment of a lighting device according to the invention, - Figure 2 illustrates schematically, in a first sectional view in an XZ plane at the first part of the light guide, the device d lighting of Figure 1, - Figure 3 illustrates schematically, in a second sectional view in an XZ plane at the second part of the light guide, the lighting device of Figure 1, - Figure 4 illustrates schematically, in a first sectional view in an XZ plane at the level of the first part of the light guide, a second embodiment of a lighting device according to the invention, and - Figure 5 schematically illustrates, in a second sectional view in an XZ plane at the level of the second part of the light guide, a second embodiment of a lighting device according to the invention. The purpose of the invention is in particular to propose a multifunctional ED lighting device intended to equip a vehicle comprising a PI license plate to be lit. It is recalled that the term “lighting device” means here a light device capable of ensuring at least two photometric lighting or signaling functions regulated for a vehicle.

It is considered in what follows, by way of nonlimiting example, that the vehicle is of the automobile type. It’s, for example, a car. However, the invention is not limited to this type of vehicle. Indeed, it concerns any vehicle (land, sea (or river), or air), as long as it includes at least one license plate to be lit.

Furthermore, it is considered in what follows, by way of nonlimiting example, that the lighting device DE is intended to be part of an optical unit BO to be installed at the rear of a vehicle, for example in a rear bumper or bumper or in a rear trunk door or tailgate. But it could itself constitute an optical unit. In this case, it must include a housing BB and a protective glass GP together delimiting a cavity housing an electronic card CE equipped with photon sources SP and at least one light guide GL.

Such a BB housing can be produced by molding an opaque and rigid material, such as for example a plastic or synthetic material. The protective glass (or screen) can be made of a translucent material (for example crystal-colored), and rigid, such as for example a plastic or synthetic material. In this case, it can be produced by molding.

In FIGS. 1 to 5, the direction X is a so-called longitudinal direction because it is intended to be parallel to the lateral (or longitudinal) sides of the vehicle (which comprise the side doors), the direction Y is a so-called transverse direction due to the fact that it is perpendicular to the lateral sides of the vehicle and therefore perpendicular to the longitudinal direction X, and the direction Z is a direction called vertical because it is parallel to the vertical direction of the vehicle and therefore perpendicular to the longitudinal directions X and transverse Y.

As illustrated in FIG. 1, a lighting device DE according to the invention comprises an electronic card CE, on which photon sources SP are installed, and at least one light guide GL.

The electronic card CE includes, in addition to the photon sources SP, control means responsible for controlling the operations of the latter (SP). This CE electronic card can, for example, be a printed circuit board of the PCB (“Printed Circuit Board”) type.

Each source of SP photons can, for example, comprise at least one light-emitting diode (or LED) or at least one laser diode, since this makes it possible to significantly reduce the bulk and the consumption of electrical energy. But in an alternative embodiment each source of SP photons could be a bulb.

The light guide GL is preferably of the flat type and comprises a central part situated between a rear end E1 and a front end E2. It will be understood that this central part PC is extended on both sides by the rear ends E1 and front E2, and is dedicated to guiding the photons.

The concepts of front and rear must be understood here in relation to the direction of propagation of at least part of the photons in the light guide GL from a source of photons SP to a front face of the front end E2 of the GL light guide. The rear end E1 has an input area which is supplied with photons by the SP photon sources. The front end E2 delivers part of the photons guided by the central part from the rear end E1.

The light guide GL comprises at least two parts Pj arranged so as to guide photons participating in the lighting function of the license plate PI and photometric function up to output faces FSj having normals of different directions, one of these output faces FS1 or FS5 being traversed by guided photons in order to illuminate the license plate PI.

The term “normal” is understood here to mean a direction perpendicular to the general tangent (or mean) of an exit face FSj of a part Pj of the light guide GL.

Thus, there is a multifunction ED lighting device, all integrated, in which the electronic card CE is shared to support the sources of SP photons and their control means, which makes it possible to have only one power supply and control harness for several photometric functions and therefore to facilitate integration into a vehicle. This also makes it possible to reduce costs, and possibly to involve the lighting device DE, or the optical unit BO which contains the latter (DE), in the style of the vehicle.

It will be noted that each photometric function other than the lighting function of the license plate PI can, for example, be chosen from a reversing light function, a fog light function, a brake light function, a position light function, and a direction change indicator (or flashing) function. Generally speaking, it can be any signaling function. It is also important to note that the parts Pj of the light guide GL can be independent (different parts) or be monobloc (by being part of the same part).

It should also be noted that the light guide GL can, for example, be produced by molding a material such as polycarbonate (or PC) or poly methyl methacrylate (or PMMA).

It will also be noted that in the example illustrated without limitation in FIG. 1, the light guide GL comprises five parts P1 to P5 (j = 1 to 5). But the number of parts Pj can take any value greater than or equal to two (2). For example, here, the first part P1 (j = 1) is dedicated to the lighting function of the license plate PI, the second part P2 (j = 2) is dedicated to a reversing light function, the third part P3 (j = 3) is dedicated to a fog light function, the fourth part P4 (j = 4) is dedicated to the reversing light function, and the fifth part P5 (j = 5) is dedicated to the lighting function of the PI license plate. This is only an illustrative example. Indeed, the lighting device DE could be dedicated only to the lighting function of the license plate PI and to the reversing light function, or else to the lighting function of the PI license plate and fog light function.

At least two embodiments of the DE lighting device can be envisaged.

A first embodiment is illustrated in FIGS. 1 to 3. It is suitable for supplying the light guide GL by the "edge" of the rear side. In this case, the rear faces F1 j of the rear end E1 are photon entry faces because they are located opposite the photon sources SP, and their surfaces are calculated so that the photons which pass through them can go to the exit faces FSj. These surfaces may possibly be flat.

In the example illustrated in FIG. 1, the front faces FR1 and FR5 of the first P1 and fifth P5 parts of the light guide GL are reflection faces whose surfaces are calculated so as to reflect the photons which reach them in the direction of exit faces FS1 and FS5 (which are dedicated to the lighting function of the license plate PI) so that they pass through them and go towards the license plate PI placed under the optical unit BO. Here, as illustrated in FIGS. 1 and 2, the exit faces FS1 and FS5 form part of the "lower" face of the light guide GL. The rear faces F1 j are here all inclined at 90 ° (and therefore vertical). Here, as illustrated in FIGS. 1 and 3, the output faces FS2 to FS4 are part of the front face of the light guide GL, and their normals make an angle of 90 ° relative to the normals of the output faces FS1 and FS5 . However, the angle between the normals of the output faces FSj with different orientations can take any non-zero value, as required.

Note that in this first illustrated embodiment, the output faces FSj have only two different orientations (and therefore two different normals), but there could be as many different orientations (or normal) as there are of output faces FSj, in particular when the number of different photometric functions provided by the lighting device DE is equal to the number of different orientations.

It will also be noted that it is also possible to add a collimating optic to the input of each rear face F1j to improve the efficiency of photon injection into the light guide GL.

It will also be noted that the outlet surfaces FS2 to FS4 can be fitted with optics or a graining to diffuse the light in order to comply with the regulations.

It will also be noted that the surfaces of the front faces FR1 and FR5 (ensuring the reflection) could be calculated so as to reflect the photons upwards (rather than downwards) in order to illuminate a license plate PI placed above of the optical unit BO.

A second embodiment is partially illustrated in FIGS. 4 and 5. It is suitable for supplying the light guide GL from above the rear end E1. In this case, the upper face F3 (but it could just as easily be the lower face F4) serves as the photon entry face because it is located opposite the photon sources SP. Furthermore, the rear faces F1 j of the rear end E1 are faces which reflect in the light guide GL of the photons coming from the input face (here the upper face F3), at the rear end E1 , and through which the photons penetrate. These rear faces F1 j may, for example and as illustrated, have inclinations (and therefore normal) differing by 45 ° between them.

We can also add a collimating lens on the input (upper) face F3 to facilitate the injection of photons into the light guide GL.

The reflection provided by the rear faces F1j can be obtained in different ways on their external surface, and in particular by the definition of a calculated surface (for example derived from a parabola), a surface treatment and / or the definition of facets and / or three-dimensional elements inducing internal reflections in one or more preferred directions. The surface treatment can, for example, consist of depositing a reflective coating on the external surface. The three-dimensional elements can, for example, be prisms, diopters, ridges or grooves, ribs, or micro-studs.

In the example illustrated in FIG. 4, the rear face F11 of a first part P1 of the light guide GL is inclined at 90 ° (and therefore vertical) in order to allow the photons from certain photon sources SP to propagate towards the exit face FS1 in order to cross it (here down) to illuminate a license plate (not shown). Here, the exit face FS1 is part of the lower face F4 of the light guide GL. For its part, and as illustrated in FIG. 5, the rear face F12 of a second part P2 of the light guide GL is inclined at -45 ° in order to deflect the photons coming from certain other sources of photons SP towards the face of FS2 output to exit in a general (or average) direction dg (here horizontal towards the rear). However, in an alternative embodiment, the rear face F12 of a second part P2 of the light guide GL could be a calculated surface. Here, the output face FS2 is part of the front face of the light guide GL.

It will be noted that by tilting the rear face F11 of the first part P1 of the light guide GL at + 45 ° (or by giving a calculated surface to this rear face F11), while placing photon sources SP opposite the underside, lighting can be obtained from a license plate placed above the DE lighting device.

It will also be noted that in this second illustrated embodiment, the outlet faces FS1 and FS2 have normals (or inclinations) making an angle of 90 °. However, the angle between the normals of the output faces FSj with different orientations can take any non-zero value, as required.

It will also be noted that in this second illustrated embodiment, the output faces FSj have only two different (or normal) orientations, but there could be as many different (or normal) orientations as there are faces. FSj output, in particular when the number of different photometric functions provided by the lighting device DE is equal to the number of different orientations.

It will also be noted that when the lighting device DE performs photometric functions requiring different colors, it is possible either to use parts Pj of the light guide GL of different colors, or to use sources SP emitting photons of corresponding wavelengths to these different colors. In the first alternative, materials presenting the different colors are injected into the mold to define the light guide GL. In the second alternative, separators (or masks) must be provided between the neighboring photon sources SP, offering different colors and supplying neighboring parts Pj, up to the input face of the photons.

It will also be noted that when the light guide GL is in one piece and its lighting device DE must provide photometric functions requiring different colors, the neighboring parts Pj and Pj 'must be optically isolated (with j' = j + 1 or j-1) so that photons propagating in a part Pj associated with a color do not pass into the neighboring part Pj 'associated with another color. This optical isolation can be done by defining a very fine and opaque interface (for example black) between the neighboring parts Pj and Pj ’by injection into the mold of the light guide GL, when the latter (GL) is in one piece. As a variant, this optical isolation can, for example, be done by inserting an opaque interface mask (for example black) between the neighboring parts Pj and Pj ’, when the light guide GL is made up of several parts.

It will also be noted that the front face of the light guide GL may possibly have on its external surface, at the level of at least one of its parts Pj, a three-dimensional appearance (or relief) resulting from the definition of facets and / or three-dimensional elements (prisms, ridges, grooves, ribs or micro-studs), for example.

It will also be noted that the visual appearance of the front face of the light guide GL, at the level of each part Pj, can result from the shape given by the molding and / or from the presence of at least one mask affixed on this face. before and consisting for example of a film of paint.

Claims (10)

1. Lighting device (DE) for a vehicle comprising a license plate (PI), said device (DE) comprising an electronic card (CE), on which photon sources (SP) are installed, and at least a light guide (GL), comprising a rear end (E1) supplied with photons by said photon sources (SP) and a front end (E2) delivering photons guided from said rear end (E1), characterized in that said light guide (GL) comprises at least two parts (Pj) guiding photons participating in the lighting function of said license plate (PI) and photometric function up to exit faces (FSj) having normal of different directions, one of said exit faces (FSj) being traversed by guided photons in order to illuminate said license plate (PI). 2. Device according to claim 1, characterized in that said rear end (E1) comprises rear faces (F1j) having the same inclination. 3. Device according to claim 1 or 2, characterized in that said outlet faces (FSj) have normals making an angle of 90 °. 4. Device according to one of claims 1 to 3, characterized in that said rear end (E1) comprises rear faces (F1j) constituting entry faces through which said photons penetrate. 5. Device according to one of claims 1 to 3, characterized in that said rear end (E1) comprises rear faces (F1j) constituting faces reflecting in said light guide (GL) photons from a face d input (F3) of said rear end (E1) through which said photons penetrate. 6. Device according to one of claims 1 to 5, characterized in that said light guide (GL) comprises at least one other part (Pj) guiding photons participating in another photometric function to another exit face (FSj) having a normal having a normal different from that of said exit face (FSj) crossed by guided photons illuminating said license plate (PI). 7. Device according to one of claims 1 to 6, characterized in that each photometric function is chosen from a reversing light function, a fog light function, a stop light function, a position light function , and a direction change indicator function. 8. Device according to one of claims 1 to 7, characterized in that said light guide (GL) is of the flat type. 9. Optical unit (BO) for a vehicle comprising a license plate (RI), said optical unit (BO) comprising a housing (BB) and a protective glass (GP) together delimiting a cavity, characterized in that said cavity houses a lighting device (DE) according to one of the preceding claims. 10. Vehicle comprising a license plate (PI), characterized in that it comprises at least one lighting device (DE) according to one of claims 1 to 8 and / or at least one optical unit (BO) according to claim 9.