EP2422130B1 - Headlamp module for vehicle, having an improved high beam function - Google Patents

Description

The invention relates to a lighting module, in particular for a motor vehicle, the lighting module comprising a first lighting function of the dipped type with an essentially horizontal cut-off of the beam. More particularly, the invention relates to a lighting module comprising a second high-beam type lighting function ensured by an additional beam supplementing the high-beam.

A lighting module comprising two reflectors of the ellipsoidal type is known from the patent document US 4,914,747 . These two reflectors correspond to half-ellipsoids and are superposed with their reflective surfaces oriented towards each other, ie oppositely. The module comprises a specific light source for the upper reflector and a common light source for the two reflectors, the specific light source being located at the level of the focus of the upper reflector to participate in the formation of a dipped type lighting beam and the common light source being located at the focus of the lower reflector to participate in the formation of a road-type lighting beam. A horizontal mask with a cutting edge is provided close to the second focal points of the two reflectors. A lens is arranged after the cover with its optical axis coinciding with the optical axis of the module. The lens is arranged so that its first focal point is close to the second focal points of the reflectors. To form the code beam, the light rays emitted by the specific light source of the upper reflector are reflected by the internal surface of the reflector approximately towards the second focal point of the reflector. Part of the rays pass in front of the cut edge of the cover. These rays encounter the lens in its lower half and are then refracted upwards. The mask conceals part of the rays which would otherwise encounter the lens in its lower half and would constitute the upper part of the beam emitted after passing through the lens. The dipped beam thus has an upper limit called cutoff. To form the driving beam, the light rays emitted by the common light source are reflected by the upper reflector towards the bottom of the upper half of the lens and also by the lower reflector towards the second focal point of the reflector. Of Similar to the rays emitted by the specific light source of the upper reflector, part of the rays pass in front of the cover and meet the upper half of the lens. Another part of the rays is reflected by the mask or reflected by a reflecting part of the latter, to then be refracted by the lower part of the lens in order to form the upper part of the beam, which has a low cut-off. The position of the shield is therefore decisive for cutting off the upper part of the beam, which is added to the lower part of the beam coming from the lower reflector. This superposition makes it possible to obtain a beam with a view to ensuring the route function. This module has a zone of weaker lighting at the level of the cut in the road type beam and corresponds to a particular embodiment of US 4,914,747 . In addition, the lower part of the beam is particular because it comes from an unfocused source. US 2009/0097268 A1 also shows a lighting module comprising two concave reflectors, a cover and an optical element.

The object of the present invention is to obtain a compact device making it possible to participate in the generation of two beams.

The object of the present invention is a lighting module, in particular for a motor vehicle, according to claim 1. Optional additional characteristics of this lighting module are presented in dependent claims 2 to 10. This lighting module can be comprised in a lighting device in particular for a motor vehicle as described in the dependent claims 11 and 12.

A compact module is thus obtained which makes it possible to emit two complementary beams. Indeed, by positioning a first light source at a first focus of the first reflector, the first light source illuminating only in the direction of the first reflector, and by positioning a second light source at the first focus of the second reflector, the second light source illuminating only in the direction of the second reflector, the beam generated by the first reflector will have a shape cut-off approximately complementary to that of the beam generated by the second reflector. A complete beam without relatively homogeneous cut-off is thus obtained, when the two sources are switched on, and a clean cut-off beam, when only one of the sources is switched on. The cutoff is sharp because the cutoff edge is focused, since it is positioned at the focal point of the corresponding reflector. With this first reflector with two reflection faces, it is possible to use two light sources compactly in this module. In this case, a first light source is positioned at the first focus of one of the reflection surfaces of the first reflector, and a second light source is positioned at the first focus of the other reflection surface of the first reflector. Thus, it is possible to obtain a beam generated by the first reflector with a shape cut-off approximately complementary to that of the beam generated by the second reflector, by means of a first reflector with two light sources and an optical element, such as a lens, common to the two reflecting faces associated with the two sources bright. We thus gain in compactness. This is particularly advantageous when the light sources are light emitting diodes. This notably makes it possible to use two sources of lesser power, instead of a single one.

The optical axes of the first and of the second reflectors are in particular oriented globally in the same direction. That is to say that when the optical axis of the first reflector is oriented towards the front of the vehicle, the optical axis of the second reflector is also oriented towards the front of the vehicle.

Thus, for example, if the first reflector is positioned at the top, when it is mounted in a vehicle, it can generate a beam of the dipped beam type or participating in a dipped beam, when the first source is on. To switch to high beam, the second light source is switched on and the beam generated by the second reflector then complements that of the first reflector, to form a high beam.

Preferably, the curved profile of the cut-off edge of the second module of the lighting device described by claim 11 is globally centered on the optical axis of the module.

This module allows when the curvature is convex upwards, the first reflector being oriented upwards, to obtain a beam with a horizontal upper cut-off, with the exception of a curved depression, or rounded, oriented downwards.

This makes it possible to superimpose this beam with a beam having a different cutoff at the center, for example a cutoff of the oblique cutoff type of a dipped beam, without inhomogeneity due to a slight offset of the cutoffs at the center of the beams.

Preferably, the curved profile is present on the two reflecting and opposite surfaces of the bending machine.

Preferably, the curved profile is limited to a central part of the cover, the rest being essentially flat.

According to the invention, the first face of the cover and the second face of the cover meet in a cut-off edge. Preferably, the second focal points of the first and of the second reflector are merged into a second common focal point, the cutting edge being positioned at the level of the second common focal point.

The cut made by such a module has the particularity that it thus compensates for the loss or inhomogeneity resulting from the non-zero thickness of the mask and the rounding of its cut-off edge. Indeed, the cutting of the beam of the first reflector is thus practically coincident with the cutting of the second reflector beam. It is for example possible to obtain a homogeneous main beam.

Preferably, at least one of the first and second faces of the mask are reflective. A better recovery of the luminous flux is thus obtained. Indeed, the rays meeting the reflective surface of the shield will be sent forwards and participate in the formation of the beam. Thus we will obtain a cut-off beam as with a mask without reflecting surface but more intense. Subsequently, caches with a reflective surface will be referred to as a folder.

Preferably, the cover is a thin element whose complex profile decreases from the cut edge towards the rear of the module so as to form a complex surface.

Preferably, the complex surface corresponds to a centered thin band of the folder.

Preferably, the cut edge has an essentially straight profile when projected into the general plane of the folder.

Preferably, the first light source comprises a light-emitting diode, or LED, emitting in an overall direction oriented towards the first reflector, and the second light source comprises an LED emitting in an overall direction oriented towards the second reflector. LEDs comprise a substrate supporting a semiconductor element, which generates light when supplied with electric current. LEDs generally emit a cone of light oriented on one side of the half-plane containing the substrate, side being that where the semiconductor element is located. The axis of this cone corresponds to the global emission direction of the LED.

According to a particularly advantageous embodiment, the light sources are carried by the cover, the first light source on the first face of the cover and the second on the second face of the cover.

The invention also relates to a lighting device, in particular for a motor vehicle, according to claim 11.

This device makes it possible to minimize the errors in the central part of the beam projected in road mode. In addition, the superposition of the beams coming from the different modules allows a certain freedom in terms of adjustment precision in a horizontal plane due to the covering of the projecting central part of the beam of the first module by the central part curved downwards from the harness of the second module.

According to a preferred variant embodiment of this lighting device, the first lighting module comprises a second lighting function of the road type where an additional beam complements the beam of the first function.

According to a preferred variant embodiment of this lighting device, the second lighting module comprises a cutting edge of constant thickness so that the second reflector of the second module makes it possible to generate a third beam having a lower cutoff with a curvature complementary to the curvature of the upper cutoff of the second beam.

The invention also relates to a lighting device, in particular for a motor vehicle, comprising: a first lighting module comprising a first low-beam type lighting function with an essentially horizontal cut-off of the emitted beam, the cut-off having a projection at its central part ; a second lighting module separate from the first and ensuring a lighting function intended to supplement the beam of the first module ensuring a road-type lighting function, the lighting function of the second module comprising a low cut-off such that it covers the beam of the first module at least in its central part.

The low cut-off of the beam of the second module can be ensured by a cover of suitable profile positioned close to the focus of convergence of the rays coming from the module. The profile of the cut is advantageously essentially horizontal with a central part slightly curved downwards so as to cover the projection of the cut of the first module.

According to the invention, each reflection face of the first reflector is included in a portion of an ellipsoid, the two portions of ellipsoids being secant along a line of separation separating the two reflection faces. The shape of this portion may not be strictly that of an ellipsoid and may be approximately ellipsoid. Advantageously, the two reflection faces join at said separation line.

Preferably, the optical axes of the two reflection faces form between them an angle of between 20 and 40 degrees, preferably between 25 and 37 degrees, in particular 31 or 35 degrees. These values make it possible to improve the quantity of light focused by the reflectors.

Preferably, a first light-emitting diode is positioned at the first focus of one of the reflection faces and a second light-emitting diode is positioned at the first focus of the other reflection face. According to an exemplary embodiment, each light-emitting diode comprises a reference axis. Preferably, the reference axes of the light-emitting diodes form between them an angle of between 20 and 30 degrees. This range of values allows more freedom in the positioning of the LEDs. This advantageously allows these reference axes of the light-emitting diodes to make between them an angle different from the angle which the optical axes of the reflection faces of the first reflector make between them. For example, this angle between the reference axes of the LEDs can be 26 degrees while that between the optical axes of the reflection faces of the first reflector is 31 or 35 degrees. The reference axes can correspond for these LEDs to the passing axis by the corresponding LED and perpendicular to one of the long sides of the emitting surface of the LED, this emitting surface being rectangular.

Advantageously, the light-emitting surfaces of the light-emitting diodes are substantially in a plane passing through the optical axis of the lighting unit. Their center is preferably in the plane passing through the optical axis of the lighting unit, generally corresponding to the optical axis of the lens.

Advantageously, the second reflector of the module comprises a light-emitting diode, located at the first focal point of the second reflector and located below the optical axis, in particular at 11 mm below the optical axis.

In the present invention, preferably, the reflective properties of the reflective surfaces are conferred by a coating of reflective material deposited on a part conferring the desired shape on the reflector. For example, by aluminating a reflector of generally elliptical shape.

Other characteristics and advantages of the invention will appear below in the detailed description of the embodiments of the invention, given by way of indication and in no way limiting.

• La figure 1 est une vue schématique en perspective d'un module d'éclairage avec une plieuse présentant un bord de coupure pour conférer au faisceau émis une coupure de type code, encore appelé feu de croisement.
• La figure 2 est une vue schématique en perspective selon un autre angle du module de la figure 1.
• La figure 3 est une vue en perspective du bord de coupure de la plieuse du module des figures 1 et 2.
• La figure 4 est une vue en coupe d'un module d'éclairage comme celui des figures 1 et 2 ou encore des figures 6 et 7.
• La figure 5 illustre l'empreinte des faisceaux provenant des réflecteurs supérieurs et inférieurs, respectivement, du module des figures 1 et 2.
• La figure 6 est une vue schématique en perspective d'un module d'éclairage qui n'est pas conforme à l'invention.
• La figure 7 est une vue schématique en perspective selon un autre angle du module de la figure 6.
• La figure 8 est une vue en perspective de la plieuse du module des figures 6 et 7.
• La figure 9 illustre l'empreinte des faisceaux provenant des réflecteurs supérieurs et inférieurs, respectivement, du module des figures 6 et 7.
• La figure 10 illustre la superposition des faisceaux provenant des réflecteurs supérieurs et inférieurs du module selon les figures 1 et 2 et du module selon les figures 6 et 7.
• La figure 11 illustre par des courbes isolux l'enregistrement à une distance de 25 mètres des faisceaux des réflecteurs inférieur (a) et supérieur (b) et leur superposition (c) du module selon les figures 1 et 2 ainsi que des faisceaux des réflecteurs inférieur (d) et supérieur (e) et leur superposition (f) du module selon les figures 6 et 7. La partie (g) de la figure 11 illustre la superposition des faisceaux complets (c) et (f) des deux modules.
• La figure 12 illustre une unité d'éclairage selon la présente invention.

In the following figures:

• The figure 1 is a schematic perspective view of a lighting module with a bender having a cut-off edge to give the emitted beam a low-beam type cut, also called dipped beam.
• The figure 2 is a schematic perspective view from another angle of the module of the figure 1 .
• The picture 3 is a perspective view of the cutting edge of the folder of the module of the figures 1 and 2 .
• The figure 4 is a cross-sectional view of a lighting module like the one in figures 1 and 2 or even figures 6 and 7 .
• The figure 5 illustrates the footprint of the beams coming from the upper and lower reflectors, respectively, of the module of the figures 1 and 2 .
• The figure 6 is a schematic perspective view of a lighting module which is not in accordance with the invention.
• The figure 7 is a schematic perspective view from another angle of the module of the figure 6 .
• The figure 8 is a perspective view of the folding machine of the module figures 6 and 7 .
• The figure 9 illustrates the footprint of the beams coming from the upper and lower reflectors, respectively, of the module of the figures 6 and 7 .
• The figure 10 illustrates the superposition of the beams coming from the upper and lower reflectors of the module according to the figures 1 and 2 and module according to figures 6 and 7 .
• The figure 11 illustrates by isolux curves the recording at a distance of 25 meters of the beams of the lower (a) and upper (b) reflectors and their superimposition (c) of the module according to the figures 1 and 2 as well as beams of the lower (d) and upper (e) reflectors and their superposition (f) of the module according to the figures 6 and 7 . Part (g) of the figure 11 illustrates the superposition of the complete bundles (c) and (f) of the two modules.
• The figure 12 illustrates a lighting unit according to the present invention.

The embodiments of the invention are illustrated in the figures and described below with respect to a mounting position of the device in a vehicle as a headlamp. This type of application, although predominant, is not limiting so that the terms used such as "horizontal", "vertical", "top", "bottom", "upper", "lower" for example, in order to describe the positions of the various elements are not absolute but rather to be interpreted in a relative way describing the positions of the elements with respect to their arrangement on the figures. Lighting devices described could be mounted in other positions and/or for other applications. In addition, the relative positions of the various optical elements such as the light sources, the reflectors and the lenses expressed for simplicity of understanding by alignment of the optical axes and/or correspondence of the respective focal points are not to be interpreted in an exact manner insofar as where slight variations are conceivable or even desirable with a view, inter alia, to correcting the non-perfect character and certain optical aberrations of the optical elements or to obtaining certain additional effects. The folders represented in certain figures of the application have been deliberately enlarged for reasons of clarity of presentation.

The figure 1 is a schematic perspective view of a motor vehicle headlamp lighting module. The lighting module 1 comprises a first upper half-plane reflector 2 consisting of a double concave reflecting surface. Each of these surfaces 2a and 2b is a surface of revolution of an ellipse section around an axis of symmetry. These two surfaces intersect in the vertical median plane of module 1, thus forming an upper reflector in the form of a double bulb. The two axes of revolution or symmetry 30 and 31 of the surfaces, respectively 2b and 2a, of the reflector intersect so that the beams reflected by these surfaces converge. A light source 5, 6 of the light-emitting diode or even LED type is located approximately at the first focus of each surface 2b, 2a forming the upper reflector 2. Given the symmetry of revolution of these surfaces, the first focus of each surface is located on the axis of revolution. The second foci of the surfaces are also located on the respective axes of revolution. The surfaces 2a and 2b are oriented so that these second focal points correspond to the point of intersection 13 of the two axes.

The module 1 also comprises a lower reflector 3 also half-plane consisting of a concave reflective surface described, as for each of the double surfaces of the upper reflector, by an ellipse section in rotation around an axis of rotation 32 or symmetry. A light source 7 also of the LED type is positioned at the level of the first focal point of the lower reflector. The reflector is dimensioned and arranged with respect to the upper reflector so that its second focus corresponds to the second focus of the upper reflector.

The main optical axis 4 of module 1 passes through the plane which contains the axes of symmetry 30, 31 of the reflection surfaces 2b and 2a of the first reflector 2.

It should be noted that the reflective internal surfaces of the reflectors may not be perfectly elliptical and have one or more specific or complex profiles with a view to optimizing the light distribution in the lighting beam. This may imply that the surfaces 2a and 2b of the first reflector 2 or the surface of the second reflector 3 are not perfectly symmetrical in revolution.

An essentially planar interface is provided between the first reflector 2 and the second reflector 3, in order to ensure the connection between them and also in order to support the light sources 5, 6 and 7. These light sources are provided to emit in a half- plane, sources 5 and 6 in an upper half-plane and source 7 in a lower half-plane.

This type of light source has the particularity of being particularly compact to the point of being able to be likened approximately to a point source. Other known types of light source can however also be considered.

The light rays emanating from the light sources roughly assimilated to point sources are reflected by the reflective surfaces of the reflectors 2 and 3 and all converge towards the second common focus 13 of the reflectors. In reality, the light sources are not point-like and the shape of the reflecting surfaces are not necessarily perfectly elliptical so that the reflected rays do not all converge towards the second focus 13 but rather towards an area close to the second focus 13.

A reflective optical element 8 commonly called a "folder" is arranged on the optical axis 4 and with its front edge called the "cut-off edge" 9 close to the second focal point 13. This thin and essentially planar folder 8 comprises a surface upper reflecting surface and a lower reflecting surface. In this way, the light rays emanating from the reflectors 2 and 3 converging towards the second focal point 13 and which encounter a surface of the bender 8 are reflected.

A lens 20 is provided on the optical path of the device. This lens of the convex plane type has its focal point corresponding to the second focal point 13 of the reflectors and its optical axis coinciding with the optical axis 4 of the module so that the light rays coming from the focal point 13 are transmitted essentially parallel to the optical axis 4. Other types of convergent lens can be envisaged, such as for example a biconvex lens or else of the convergent meniscus type. A reflector of the paraboloidal mirror type is also possible. In this case, its optical axis would be essentially perpendicular or at the very least secant to the axis 4 and its focal point would coincide approximately with the focal point 13. Such a reflector would then reflect the light rays in a direction essentially parallel to its optical axis, that is to say perpendicular to the optical axis 4 or along an axis secant therewith.

The picture 2 is another schematic view of the module from the figure 1 from a different angle. This view illustrates the inclination of the upper reflector 2 with respect to the lower reflector 3. As seen previously, the axes of revolution of the surfaces 2a and 2b of the upper reflector, as well as the general optical axis 4 of the module are coplanar. On the other hand, the axis of revolution of the lower reflector 3 forms an angle α with the axis with the general optical axis 4 of the module 1. This angle is quite small, typically a few degrees and is essentially due to the fact that the folder ideally infinitely thin actually has a certain thickness. The folder actually has a triangular section in a longitudinal and vertical median plane.

The folding machine is best represented at the picture 3 which is an enlarged perspective view of the cut edge thereof. The folder 8 has a finite and increasing thickness from the cutting edge 9 towards the rear thereof. The cutting edge 9 has a projection 12 approximately at its central part, that is to say the part positioned at the level of the optical axis 4. The upper surface and the lower surface on either side of this projection 12 are essentially planar. The jump thus constitutes a discontinuity in the profile of the cut-off edge. The cut edge 11 on the right side when looking from the reflectors to the lens, i.e. the left side in the representation at the picture 3 is slightly raised relative to the opposite side 11'. The cut made by the bender will therefore obscure more rays coming from the right parts of the reflectors, that is to say the rays which will then form the left part of the beam projected by the lens 20. This left part will thus have a cut more lower than the right part of the beam, the jump creating an oblique portion. This makes it possible to obtain a code type break as shown in figure 5 .

The figure 4 is a schematic plan and sectional view along a median plane of the module of the figures 1 and 2 . The purpose of this figure is to illustrate the role of the folder and the cut it operates. One of the upper light sources 5 or 6 is shown there as well as the profile of the corresponding reflecting surface. It is therefore on this part of a section along a longitudinal median plane of one of the reflecting surfaces 2a, 2b, forming the upper reflector 2. The lower light source 7 is also represented there as well as the profile of the reflecting surface corresponding to the lower reflector 3. The folding machine 8 with a wedge-shaped section is also represented there.

The light ray 15 emitted from the first focus of the first reflector by the upper light source 5 or 6 is reflected by the reflecting surface of the upper reflector towards the second focus 13. Since the light source is not point-like, it also emits light rays slightly offset (represented in dotted lines) which after reflection by the reflecting surface will not converge exactly towards the second focal point 13. Thus, certain rays will pass through the focal point and will be refracted by the lens 20 parallel to the global optical axis 4. These rays will correspond to the upper cutoff of the lower beam 17 emitted by the module 1 and shown in figure 5 . Other rays pass in front of the cutting edge 9 and go towards the lower half of the lens. As they pass over focus 13, lens 20 will refract them downward. These rays will therefore correspond to the part of the lower beam 17 situated below the cut-off. Other rays encounter the reflective top surface of the bender and are reflected back to the top half of the lens. These rays therefore also passing above focus 13, lens 20 will also refract downward. These rays will therefore complete the part of the lower beam 17 located below the cut. It is therefore the position of the cut-off edge which is decisive for the cut-off or upper limit of the beam.

The upper light sources 5 and 6 associated with the upper reflector 2 provide the dipped type lighting function, that is to say a lighting function with an upper cut-off of the projected beam. The simplified footprint 17 of this lower illuminating beam is shown in figure 5 (this footprint is typically a projection at 25 meters from the beam). The HH axis corresponds to the horizontal axis and the VV axis corresponds to the vertical axis. This imprint does indeed include a generally horizontal cut with, however, a jump or step generated by the jump 12 of the cutting edge 11 of the bender 8. This cut-off profile is required by law in order to limit the dazzling of drivers coming against it. meaning.

The lower light source 7 and the lower reflector 3 operate in reverse with respect to the combination of the upper reflector 2 and the sources 5 and 6. Thus, a light ray 14 emitted from the first focus of the lower reflector 3 by the lower light source 7 is reflected by the reflecting surface of the lower reflector 3 towards the second focal point 13. Certain rays will pass through the focal point 13 and will be refracted by the lens 20 parallel to the global optical axis 4. These rays will correspond to the lower cut-off of the upper beam 16 emitted by module 1, shown in figure 5 . Other rays pass, for some in front of the cutting edge 9 to reach the upper part of the lens 20, and for others, meet the lower reflective surface of the bender 8 and are reflected towards the lower half of the lens. These rays therefore pass below focus 13 and lens 20 will refract them upwards; they correspond to the part of the upper bundle 16 located above the lower cutoff.

The lower light source 7 performs the road-type lighting function in combination with the upper light sources 5 and 6. The cut-off edges 9 have a constant thickness. Thus, the footprint 16 of the upper beam and the footprint 17 of the lower beam are complementary. By switching on the light sources 5, 6 and 7, a road type beam is obtained. Due to the non-zero thickness of the folder at the level of the cut-off edge, a zone of weaker illumination is present at the border between the two cut-off profiles. This is not a black area but rather a lower light area.

Another lighting module 100 similar to that of the figures 1 and 2 is illustrated in figures 6 and 7 . It is very similar to module 1 but differs essentially in that it comprises a single upper light source 105, in that the bender 108 comprises a complex surface, and in that the upper reflector 102 comprises a single reflective surface axis of rotation coinciding with the general optical axis 104 of the module 100. The presence of a single light source associated with the upper reflector means that the lighting of this module is weaker than that of the module 1 of the figures 1 and 2 . It is designed to be used in combination with module 1 to provide additional lighting. A lower light source 107 is associated with the lower reflector 103.

The 108 Folder is best illustrated at figure 8 . It is slightly domed upwards at the cut edge. It has a complex surface on both upper and lower sides. Viewed from the front from the lens 120, the folder has an upwardly domed profile, approximately centered on the optical axis and symmetrical at the cut edge. The cut edge is located at focus 113, which corresponds to the second focus of upper reflector 102 and lower reflector 103. This curved profile decreases from cut edge 109 towards the rear of the folder. The rear part of the folder is thus essentially flat. The width of the curved strip corresponds to less than one third, preferably less than one quarter, of the total width of the folder. The cut edge 109 however has a generally straight profile when viewed from above.

The figure 4 also applies to the module of figures 6 and 7 . It is a sectional view along a longitudinal vertical median plane of the lighting module 100 and illustrates the role of the bender with respect to the light rays coming from the two light sources 105 and 107.

The footprints of the beams projected by the module 100 and emanating from the two light sources 105 and 107 are illustrated in a simplified manner in the figure 9 . The HH axis corresponds to the horizontal axis and the VV axis corresponds to the vertical axis.

The imprint of the lower beam 117 is that of the upper light source 105 associated with the upper reflector 102. An essentially horizontal cut-off is indeed observed there slightly below the horizon line. We also observe the bulging part downwards in the central part of the beam. It corresponds to the complex shape of the folder 108 at the cut-off edge 109. The reflective top surface of the folder 108 at the cut-off edge is higher than the rest of the surface and therefore causes a corresponding lower cut-off. with rounded profile. The central point of the cut edge centered on the optical axis of the module is the highest and thus causes a maximum downward cut corresponding to the intersection of the cut edge of the cavity 117 with the vertical axis V-V.

The imprint 116 is that of the lower light source 107 associated with the lower reflector 103. The curved part downwards is also observed in the central part of the cut-off of the imprint 116 of the upper beam. It corresponds to the complex shape of the folder 108 at the level of the cutting edge 109, of constant thickness. The center point of the cut edge centered on the optical axis of the module is the highest and thus causes a minimum downward cut corresponding to the intersection of the cut edge of the cavity 116 with the vertical axis V-V. The association of the lower reflector 103 and the lower light source 107, according to the same principle as the lower reflector 3 and the light source 7 of the module 1, thus generates the upper beam 116 with a lower cutoff.

The figure 10 illustrates the superposition of the different beams of the two modules 1 and 100 in the central part of the projected beam. It is indeed the most important central part for the quality of vision of the driver of the vehicle. The respective breaks of the beams of the bender lighting module of the first module 1 are illustrated in solid lines. The respective cut-offs of the beams of the low beam type and of the complementary main beam type of the complex surface bender lighting module, the second module 100, are illustrated in dotted lines. It should be noted that these cuts are very schematized for reasons of clarity of presentation of the invention. Moreover, the area comprised between the corresponding cuts of the lower cavities and of the upper cavities of a lighting module is not completely absent from lighting. However, the zone in question has at the very least an irregularity or inhomogeneity of lighting which is particularly disturbing in the central part. The presence of the beam 117 of lower power (a single light source for the complex folding module against two for the folding module with the projection 12) constitutes a reinforcement of the beam 17 while respecting the step cut required by the legislation. The superposition of the beams 17 and 117 constitutes the code function of the device comprising a module according to the figures 1 and 2 and a module according to figures 6 and 7 . The road type lighting function is ensured by the superposition of the beams 17, 117, 16 and 116. figure 10 that the beam 116 potentially of similar power to the beam 16 complements it while covering the central part of the zone of inhomogeneity. This results in an improved road function from the point of view of beam homogeneity, in particular in the central part. In addition, the curved shape of the cut induced by the complex surface folder is chosen wide enough to cover the central part important for the quality of vision of the driver. The fact that this domed part sufficiently covers the stepped central part of the beams of the first module provides a certain freedom of adjustment of the two modules relative to each other at the level of the convergence of their beams.

It should be noted that other beam power levels can be considered. The choice of a module with three light sources for the jump folder and a module with two light sources for the complex surface folder is purely by way of example. For example, the jump folder module could have two light sources. One could also combine a jump folder module with two complex folder modules.

The figure 11 illustrates by isolux curves the luminosity of the different beams projected at 25 meters. The beam (b) corresponds to the code type beam of the upper reflector 2 of the first module 1. It corresponds to the imprint 17 of the figure 5 . the beam (a) corresponds to the complementary beam of the lower reflector 3 of the first module 1. It corresponds to the imprint 16 of the figure 5 . Beam (c) corresponds to the superposition of the two beams.

The beam (e) corresponds to the lower beam of the upper reflector 102 of the second module 100, i.e. the imprint 117 in figure 9 . The beam (d) corresponds to the upper beam of the lower reflector 103 of the second module 100, i.e. the imprint 116 in figure 9 . The beam (f) corresponds to the superposition of the two beams (e) and (d). The beam (g) corresponds to the superposition of the combined beams (c) and (f) of the two lighting modules 1 and 100. This beam (g) corresponds to a main beam. It can be seen that the lighting irregularities are corrected by the conjunction of the beams of the two modules. The rounded curvature downwards of the lower cutoff of the beam (d), that is to say corresponding to the lower reflector 103 of the second module 100, makes it possible to reinforce the lighting in the central zone in high beam.

It should be noted that to obtain a low beam, or low beam, only the upper light sources 105 and 5 and 6 are lit. The beams (b) and (e) are then superimposed. Due to the downward curved cutoff for the beam (e) of the upper reflector 102 of the second module, there is no problem of alignment of the cutoffs in the central zone of the dipped beam.

• un premier réflecteur 2 comprenant au moins deux faces de réflexion 2a et 2b, chacune présentant un premier foyer F1 et F2 et un deuxième foyer 13 alignés sur un axe optique 31, 30, chaque face étant apte à réfléchir les rayons lumineux partant de son premier foyer F1 et F2 vers son second foyer 13, les axes optiques 31, 30 des deux faces de réflexion 2a et 2b étant en intersection au niveau de leurs seconds foyers 13 ;
• un cache 8 agencé pour créer une coupure dans le faisceau lumineux généré par ladite unité d'éclairage ;
• un élément optique 20 comprenant un premier foyer FL situé sur le bord de coupure 9 du cache,

les faces de réflexion 2a et 2b du premier réflecteur, le cache 8 et l'élément optique 20 étant agencés de manière à permettre la génération d'un faisceau lumineux à coupure.The figure 12 illustrates a lighting unit 202 for generating a cut-off light beam, in particular for a low beam headlight for a motor vehicle, this lighting unit comprising:

• a first reflector 2 comprising at least two reflection faces 2a and 2b, each having a first focus F1 and F2 and a second focus 13 aligned on an optical axis 31, 30, each face being capable of reflecting the light rays originating from its first focal point F1 and F2 towards its second focal point 13, the optical axes 31, 30 of the two reflection faces 2a and 2b being in intersection at the level of their second focal points 13;
• a mask 8 arranged to create a cut in the light beam generated by said lighting unit;
• an optical element 20 comprising a first focus FL located on the cut-off edge 9 of the mask,

the reflection faces 2a and 2b of the first reflector, the mask 8 and the optical element 20 being arranged so as to allow the generation of a cut-off light beam.

The optical element 20 of the lighting unit 202 is a converging lens, admitting a focal point FL positioned at the level of the cut-off edge of the mask.

The optical axes 31, 30 of the two reflection faces 2a and 2b of the first reflector 2 form between them an angle α of between 20 and 40 degrees, preferably between 25 and 37 degrees, in particular 31 or 35 degrees.

Each reflection face 2a and 2b of the first reflector 2 is included in a portion of an ellipsoid, the two portions of ellipsoids being secant along a line of separation 2c separating the two reflection faces. The shape of this portion may not be strictly that of an ellipsoid and may be approximately ellipsoid. Advantageously, the two reflection faces 2a and 2b join at the level of said line of separation 2c.

Two light-emitting diodes 6 and 5 are positioned at the first focal points of each of the reflection faces 2a and 2b. Each light-emitting diode 5, 6 comprises a reference axis 5a, 6a, these reference axes of the light-emitting diodes making between them an angle β, different from the angle α that the optical axes 31, 30 of the reflection faces make between them. 2a and 2b of the first reflector 2. In this example, the reference axes 5a and 6a correspond for these LEDs 5 and 6 to the axis passing through the corresponding LED and perpendicular to one of the long sides 5b, 6b of the surface emitter of the LED, this emitting surface being rectangular.

This lighting unit can be used in a previously described module. It is thus possible to have a lighting module 1 according to the first object of the invention, illustrated in figures 1 to 4 , in which the first reflector 2, the cover 8 and the optical element 20 are a lighting unit 202 as previously described. Advantageously, the second reflector 3 of this module 1 comprises a light-emitting diode 7, located at the first focal point of the second reflector 3 and located below the optical axis 4 of the module, in particular 11 mm below the optical axis.

Claims (12)

1. Lighting module (1) notably for motor vehicles comprising:

   - a first concave reflector (2) comprising at least a first and a second focal point aligned on an optical axis of the first reflector, in such a manner that a majority of light rays leaving from this first focal point and reflected by the first reflector (2) converge towards this second focal point (13);

   - a second concave reflector (3) comprising at least a first and a second focal point aligned on an optical axis of the second reflector (3), in such a manner that a majority of light rays leaving from this first focal point and reflected by the second reflector (3) converge towards this second focal point (13), the first (2) and the second (3) reflectors having a truncated circumference in such a manner that the reflecting face of the first reflector (2) is oriented towards that of the second reflector (3);

   - a shield (8) disposed within a plane somewhere between the first (2) and the second (3) reflectors, said shield having a first face facing the reflecting surface of the first reflector (2) and a second face facing the reflecting surface of the second reflector (3), said shield comprising a cutoff edge (9) joining its first and its second face;

   - an optical element (20) comprising a first focal point (FL) situated in a plane perpendicular to the optical axis of the module and passing through the cutoff edge;

   said cutoff edge (9) being situated at the second focal point (13) of the first reflector and at the second focal point (13) of the second reflector, said module being characterized in that the first reflector (2) of the module (1) comprises two intersecting reflection surfaces (2a and 2b), each being a surface of revolution described by an ellipse in a half-plane having a first and a second focal point (F1 and F2) aligned on an optical axis (31, 30), the optical axes (31, 30) of the two surfaces of revolution (2a and 2b) intersecting at their second focal point (13),
   and in that the lighting module (1) comprises a first light source (5) situated at the first focal point (F1) of one of the reflection surfaces (2a) of the first reflector (2), another light source (6) positioned at the first focal point (F2) of the other reflection surface (2b) of the first reflector, and a second light source (7) situated approximately at the first focal point of the second reflector (3), the first light source only illuminating in the direction of the first reflector and the second light source only illuminating in the direction of the second reflector.
2. Module according to the preceding claim, characterized in that the second focal point of the first reflector (2) and the second focal point of the second reflector (3) coincide at a second common focal point (13), the cutoff edge (9) being positioned at the second common focal point.
3. Module according to either of the preceding claims, characterized in that at least one of the first and second faces of the shield (8) are reflecting.
4. Module according to one of the preceding claims, characterized in that the first light source (5) comprises an LED emitting in a general direction oriented towards the first reflector (2), and in that the second light source (7) comprises an LED emitting in a general direction oriented towards the second reflector (3).
5. Module according to one of the preceding claims, characterized in that the light sources (5, 6, 7) are carried by the shield (8), the first light source (5) on the first face of the shield and the second (7) on the second face of the shield.
6. Lighting module according to Claim 1, wherein the first reflector (2), the shield (8) and the optical element (20) are for generating a light beam with cutoff, notably for a low-beam motor-vehicle headlight, in which:

   - each reflection face (2a and 2b) is able to reflect the light rays leaving from its first focal point (F1 and F2) towards its second focal point (13);

   - the shield (8) is configured to create a cutoff in the light beam generated by said lighting module;

   - the first focal point (FL) of the optical element (20) is situated on the cutoff edge (9) of the shield,

   the reflection faces of the first reflector, the shield and the optical element being configured in such a manner as to allow the generation of a light beam with cutoff.
7. Lighting module according to Claim 6, in which the optical axes (31, 30) of the two reflection faces (2a and 2b) of the first reflector (2) make an angle between them (α) in the range between 20 and 40 degrees, preferably between 25 and 37 degrees, notably 31 or 35 degrees.
8. Lighting module according to either of Claims 6 and 7, characterized in that the light sources (5, 6, 7) are light-emitting diodes.
9. Lighting module according to Claims 7 and 8 in combination, in which said first light source (5) and said other light source (6) each comprise a reference axis (5a, 6a), these reference axes of these light-emitting diodes making an angle (β) between them different from the angle (α) made between the optical axes (30, 31) of the reflection faces (2b and 2a) of the first reflector (2).
10. Lighting module according to one of Claims 6 to 9 when taken in combination with Claim 8, in which, in the second reflector (3), the light-emitting diode (7), situated at the first focal point of the second reflector (3), is situated below the optical axis (4), notably 11 mm below the optical axis.
11. Lighting device notably for motor vehicles comprising:

    - a first lighting module (1) according to one of the preceding claims and comprising a first lighting function of the low-beam type, the cutoff edge (9) of said first module having two straight parts (11, 11') offset with respect to one another by a kink (12) situated in the central part of this cutoff edge (9), in order to form, in association with the rays reflected (15) by the first reflector (2) of the first module, a first beam (17) of low-beam type having an oblique cutoff portion;

    - a second lighting module (100), the first (1) and second modules being disposed next to one another in such a manner that their beams converge,
    in which the second lighting module (100) comprises:

    - a first concave reflector (102) comprising at least a first and a second focal point aligned on an optical axis of this first reflector, in such a manner that a majority of light rays leaving from this first focal point and reflected by this first reflector (102) converge towards this second focal point (113);

    - a second concave reflector (103) comprising at least a first and a second focal point aligned on an optical axis of this second reflector (103), in such a manner that a majority of light rays leaving from this first focal point and reflected by the second reflector (103) converge towards this second focal point (113), the first (102) and the second (103) reflectors of the second module having a truncated circumference in such a manner that the reflecting face of this first reflector (102) is oriented towards that of the second reflector (103);

    - a shield (108) disposed within a plane somewhere between the first (102) and the second (103) reflectors of the second module, this shield having a first face facing the reflecting surface of the first reflector (102) of the second module and a second face facing the reflecting surface of the second reflector (103) of the second module, this shield comprising a cutoff edge (109) joining its first and its second face;

    - an optical element (120) comprising a first focal point (FL) situated in a plane perpendicular to the optical axis of the second module and passing through the cutoff edge of the latter;

    said cutoff edge (9, 109) of the second module being situated at the second focal point (113) of the first reflector of the second module and at the second focal point (113) of the second reflector of the second module, and the shield (108) of the second module comprises at least on its cutoff edge (109) a profile curved in said perpendicular plane, so as to affect in a corresponding manner the cutoff of a beam coming from one of the reflectors (103, 102) of the second module,

    the second lighting module (100) comprising a first light source (105) situated approximately at the first focal point of its first reflector (102) and a second light source (107) situated approximately at the first focal point of its second reflector (103), this first light source only illuminating in the direction of the first reflector and this second light source only illuminating in the direction of this second reflector, and the curved profile of the corresponding cutoff edge (109) being centred globally on the optical axis (104) of the second module, so as to form, in association with the rays reflected (115) by the first reflector (102) of the second module, a second beam (117) exhibiting an upper cutoff with a curved profile oriented downwards;

    the first and second modules (1, 100) being oriented in such a manner that the oblique portion of the cutoff of the first beam (17) converges towards the curved profile of the beam of the second beam (117).
12. Lighting device according to Claim 11, characterized in that the cutoff edge (109) of the second module is of constant thickness, such that the second reflector (103) of the second module allows a third beam (116) to be generated that exhibits a lower cutoff with a complementary curvature to the curvature of the upper cutoff of the second beam (117).

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