EP3141803B1 - Lighting module for lighting and/or signalling of a motor vehicle - Google Patents

Description

The present invention relates to the field of light modules used for lighting and/or signaling motor vehicles, and it applies more particularly to light modules comprising a cover arranged across the light rays for the formation of a beam specific. For greater clarity, it will, in the following, be presented and described in its preferred but not exclusive application to motor vehicle lighting projectors.

We know of headlamps used for the lighting and/or signaling of a motor vehicle which comprises, in particular, a light emitting assembly, an elliptical type reflector whose first focus is located in the vicinity of the light emitting assembly. light, and convergent focusing means (typically, a convergent lens), a focal plane of which passes in the vicinity of the second focus of the elliptical reflector.

Furthermore, in order to offer improved vehicle lighting and/or signaling services, it is known to place a cover in the vicinity of the second focus of the elliptical reflector, said cover having an edge, also called cutting edge, arranged in the module to intercept, by its shape and its position, part of the radiation emitted by the light emitting assembly and resulting from a first reflection by the elliptical reflector, the rest of the emitted light radiation propagating normally outwards . The shape of the cutoff edge defines a cutoff profile of the emitted light beam.

Such a cover is, for example, conventionally used to modify the light beam emitted by a headlight of a vehicle when the latter is traveling on a two-way road, in particular in order to limit dazzling for the drivers of vehicles traveling in reverse. This function is known by the English term "Low Beam" (LB) and it corresponds to the traffic conditions in which the vehicle uses its low beam headlights.

The covers used to achieve this function are, in a known manner, installed fixed within a housing which accommodates the different elements of the projector. Such caches define a single cutoff profile.

Wishing to offer users ever more efficient lighting and/or signaling services for ever safer and more pleasant driving, solutions have also been sought by automobile manufacturers to modify the beam cut-off profile according to traffic conditions. .

The documents FR2796449 And FR2847655 , for example, each describe a device in which a first cover is pivotally mounted around a first axis substantially perpendicular to the optical axis of a lighting projector, and in which a second cover is pivotally mounted on the first cover . According to the document FR2796449 , the pivot axis of the second cover is substantially parallel to the optical axis of the projector, whereas, according to the document FR2847655 , the pivot axis of the second cover is substantially parallel to said first pivot axis of the first cover. In both cases, appropriate control means make it possible to define a set of relative positions of the two covers between them and in relation to the light rays emitted by the light emitting assembly of the projector, and, thus, make it possible to obtain different profiles to cut off the beam emitted by the projector. The documents DE 19 908 642 A1 And FR 2 942 024 A1 disclose light modules known from the prior art.

However, these devices are not entirely satisfactory. In fact, the cut-off profile is modified here by the interposition of the second cover, which leads to intercepting a larger part of the light rays emitted by the light emitting assembly of the projector. Furthermore, the second cover, of small dimensions, is, in such a configuration, highly subject to deformations resulting from the thermal constraints which prevail within the projector, deformations which can lead to malfunctions of said projector. Finally, the assembly formed by the two covers and the means for operating the latter is relatively bulky, and therefore cannot be inserted into any type of projector housing.

Furthermore, in the automatic management of the lights of a motor vehicle, it may be planned to modify the attitude of the light beam emitted as a function of the speed of the vehicle, to promote, when the vehicle is moving at high speed, a reading anticipated warning signs placed high on traffic lanes like highways.

The invention proposes to produce a light module in which a cover is installed while presenting the simplicity and minimal bulk of a fixed cover, while offering the possibility of adapting to different traffic conditions, and in particular the modification of high speed trim.

For this purpose, the invention relates to a light module as defined in claim 1.

• le cache comporte une zone centrale de réflexion et des zones d'extrémité s'étendant de part et d'autre de ladite zone centrale ;
• les moyens de déformation agissent sur un bord arrière du cache opposé au bord de coupure ;
• l'action des moyens de déformation sur le cache se traduit par un léger déplacement en translation ou en rotation d'au moins une partie du bord de coupure ;
• les moyens de déformation sont fixés, par des moyens appropriés, sur une base sur laquelle est monté au moins l'ensemble émetteur de lumière.

According to different characteristics of the invention, taken alone or in combination:

• the cover comprises a central reflection zone and end zones extending on either side of said central zone;
• the deformation means act on a rear edge of the cover opposite the cutting edge;
• the action of the deformation means on the cover results in a slight translational or rotational movement of at least part of the cutting edge;
• the deformation means are fixed, by appropriate means, on a base on which at least the light emitting assembly is mounted.

According to a first series of characteristics specific to an embodiment of the invention, taken alone or in combination with what has preceded, it can be provided that the deformation means comprise an actuator controlling the movement of a pusher. In this case, it is notable that the deformation means can act on the rear edge of the cover, in a direction substantially parallel to the optical axis, or in a direction substantially perpendicular to the optical axis, in the direction opposite to the optical axis. desired direction of movement of the cutting edge.

According to a second series of characteristics specific to an embodiment of the invention, taken alone or in combination with what has preceded, the deformation means may comprise a piezoelectric actuator, and in this case, it can be provided that the piezoelectric actuator is carried at least partially by the cover.

• la figure 1, qui est une vue schématique en perspective d'une partie de l'intérieur d'un boîtier de module lumineux pour l'éclairage et/ou la signalisation selon l'invention, sans que soit représenté pour autant les moyens de déformation essentiels à l'invention ;
• la figure 2, qui est une vue schématique en coupe d'un premier mode de réalisation d'un boîtier de projecteur selon l'invention, dans lequel le cache est dans une première position passive, non déformé ;
• la figure 3, qui est une vue schématique en coupe d'un premier mode de réalisation d'un boîtier de projecteur selon l'invention, dans lequel le cache est dans une deuxième position active, déformé ;
• la figure 4, qui est une vue similaire à celle de la figure 3 pour l'illustration d'une variante du premier mode de réalisation ; et
• la figure 5, qui est une vue schématique en coupe d'un deuxième mode de réalisation d'un boîtier de projecteur selon l'invention, dans lequel le cache est dans une deuxième position active, déformé.

Other characteristics and advantages of the invention will emerge on reading the description which follows, illustrated by the following figures:

• there figure 1 , which is a schematic perspective view of a part of the interior of a light module housing for lighting and/or signaling according to the invention, without however showing the deformation means essential to the invention;
• there figure 2 , which is a schematic sectional view of a first embodiment of a projector housing according to the invention, in which the cover is in a first passive position, not deformed;
• there Figure 3 , which is a schematic sectional view of a first embodiment of a projector housing according to the invention, in which the cover is in a second active position, deformed;
• there Figure 4 , which is a view similar to that of the Figure 3 for the illustration of a variant of the first embodiment; And
• there Figure 5 , which is a schematic sectional view of a second embodiment of a projector housing according to the invention, in which the cover is in a second active position, deformed.

For ease of reading, the directions "up", "down", "right" and "left" will be given, in the following, with reference to the orientation of the figure 1 . Likewise, the same element will be referenced in the same way in all the figures.

As shown in the figure 1 , a module 1 for the lighting and/or signaling of a motor vehicle comprises at least, in a known manner, a light emitting assembly, of the light-emitting diode type 2 as it was represented without its support in the figure , means for optical deflection of the rays emitted, of the elliptical reflector type 3, means of focusing 4, converging, of the rays emitted by the light emitting assembly 2 and deflected by the reflector 3, a cover 6 and a housing 7 ( partially shown on the figure 1 ) in which these different elements are housed and which is, conventionally, closed by a mirror not shown here.

The module also includes a device 5 for cooling the light emitting assembly 2 and the elliptical reflector 3, means for fixing the different elements as well as, as shown schematically on the figures 2 to 4 , a base 9 on which the light emitting assembly 2 and various control elements thereof are mounted. In reference to the figure 1 , on which the base has not been shown to make visible the other elements housed in the case, this base, of complex shape, conventionally covers the elements illustrated.

According to a preferred embodiment of the invention, the light emitting assembly 2 is composed of an assembly of light-emitting diodes (known by the acronym LED for “Light-Emitting Diodes”), which makes it possible to achieve performances high lighting levels with low electrical powers. And the optical deflection means take the form of a reflector comprising two substantially elliptical portions, facing each of which at least one light-emitting diode is arranged, substantially in the vicinity of a first focus of the corresponding elliptical reflector portion 3. The light emitted by the emitter assembly 2 is thus reflected towards the second focus of these two portions of elliptical reflector 3, arranged so that this second focus is substantially common to the two portions. The focusing means 4, for example a converging lens according to a preferred embodiment of the invention, are placed in such a way that their focal plane is located in the vicinity of the second focus of the elliptical reflector 3. The converging lens then forms an image to infinity of the light emitted by the assembly 2 and reflected by the reflector 3 at its second focus, and the beam emerging from said lens 4 is a parallel beam.

In the embodiments of the invention represented by the different figures, the light emitting assembly 2 is likened to a light source of small dimensions, made integral with the upper face of the base 9 and arranged to emit light rays towards the top, in the direction of the elliptical reflector 3. The invention is however not limited to this configuration, and it applies whatever the position of the light emitting assembly 2, insofar as the latter is placed in the vicinity of a first focus of the elliptical reflector 3. For greater clarity in the description, this configuration has however been included in the figures 2 to 5 .

According to the invention, the cover 6 is inserted on the optical axis 8 between the light emitting assembly 2 and the converging lens 4. It consists of a plate which extends substantially parallel to the base 9, here substantially horizontally. The cover comprises a central reflection zone 10 and end zones 12 arranged laterally on either side of the central zone, means for fixing to the module being arranged in each of these end zones 12 of the plate. The central reflection zone has an upper face 14, a lower face 16 and two longitudinal end edges including a rear edge 17, facing the base 9, and a front edge 18, facing the projection device, which forms a cut-off edge 18 arranged in the vicinity of the second focus of the reflector.

As visible on the figures 2 to 5 , the cover is fixed so as to extend opposite the free end of the base 9, without however being in contact with this base.

In the central reflection zone 10, as is, the sectional views of the figures 2 to 5 can show it, the cover has the shape of a beveled plate in the direction of the optical axis, with a tapered point forming the cutting edge 18 and a thicker base 20.

The upper face 14, facing the side of the module in which the part of the reflector 3 reflects the rays emitted by the light emitting assembly 2, is made of a material reflecting light, or coated with a layer of a reflective material the light. The plate constituting the cover 6 can for example be produced by stamping of a metallic material, then coated, at least on this upper face 14, with a layer of reflective material, for example a thin layer of aluminum.

As illustrated on the figure 1 , the cover 6 is fixed, at each of its ends 12, on corresponding studs 22 of the housing 7, here via fixing screws 23. The cover 6 and its fixing means within the light module according to invention are therefore of reduced bulk and very simple installation, allowing the installation of the invention on all types of projectors and vehicles.

As has been clarified, the cover 6 is placed in such a way that its cutting edge 18 is located in the vicinity of the second focus of the ellipse formed by the reflector 3, and it is also located in the vicinity of the focus of the means of focus. This cutting edge 18 intercepts part of the light rays resulting from the reflection, by the elliptical reflector 3, of the rays emitted by the light emitting assembly 2, as shown in figure 2 . The cover thus creates a horizontal cut-off in the beam and the concentration of the rays under this cut-off to produce the beam corresponding to the “low beam” mode.

In the example illustrated by figure 2 , the vast majority of the rays emitted by the light emitting assembly 2 (shown in solid lines) are reflected by the elliptical reflectors 3 in the vicinity of the second focus of the reflectors. These rays are not intercepted by the cut-off edge 18 of the cover 6 and they are therefore directed without being deflected towards the converging lens 4. Coming from the focal plane of this lens, the rays are emitted at the output of the module parallel to the axis optical, here under the horizontal plane comprising this optical axis. The few rays (shown in broken lines) which intersect the optical axis upstream of the second focus are reflected by the reflective face 14 of the cover. The angle with which they attack the converging lens generates an exit angle of the ray re-emitted by the lens such that it passes under the cutoff, that is to say that it points downwards. As has been said, the rays are concentrated under the cut.

According to the invention, the position of the cutting edge is modified to move it from a passive standard position (illustrated on the figure 2 ) to an active position (shown on the Figure 3 ) in which the cutting edge is offset vertically, that is to say in the direction perpendicular to the plane parallel to the base and including the optical axis, by relative to the optical axis, in the direction of moving away from the elliptical reflector 3, that is to say here towards the bottom.

In this active position, the rays mainly emitted by the light source (still illustrated in solid lines) continue to intersect the focal plane of the lens at the level of the second focus F2 of the elliptical reflector 3, but the few rays which come to intersect the axis optical upstream of the second focus of said reflector (still illustrated in broken lines) are no longer reflected by the cover and attack the converging lens 4 with an angle which generates an exit angle of the ray re-emitted by the lens such that it passes through above the cut, that is to say it points upwards.

It follows that the shape of the emerging beam, the sum of the rays emerging from the converging lens 4, is modified, and that this modified shape allows enhanced lighting, capable of illuminating more clearly the panels located above the road scene notably.

The light module includes means as will be described below to generate this movement of the cut-off edge on demand, to move from a standard position to an active position depending on the road conditions, and in particular when it is detected that the vehicle exceeds a determined speed.

According to the invention, the light module 1 comprises means 24 (schematically represented on the figures 2 to 5 ) deformation of the cache 6. Different embodiments have been represented, in a non-exhaustive manner, on the figures 2 to 5 : we will first describe the embodiment illustrated on the figure 2 And 3 .

The deformation means 24 consist in this first embodiment of an actuator 26, of the electric motor type, associated with a pusher 28 which exerts a longitudinal movement T1, in the direction of the optical axis, on the cover 6.

As illustrated, the actuator, the pusher and the cover are arranged so that the action of the pusher on the cover is exerted on the lower end of the rear longitudinal edge 17 of the cover. It will be understood that this rear longitudinal edge 17 of the cover extends far enough from the optical axis to provide a connection surface to the free end of the pusher. Advantageously, the actuator 26 is fixed, by appropriate means, on the base 9 on which the light emitting assembly 2 and various control elements thereof are mounted. In the example illustrated, the actuator 26 is fixed on the lower face of the base 9, that is to say the face facing away from the light source.

According to the invention, the actuator receives a control instruction, to generate a determined movement of the pusher in a direction substantially parallel to the optical axis, in a direction of retraction of the free end of the pusher 28 towards the actuator 26 (as illustrated by the direction of arrow T1 on the Figure 3 ). The free end of the pusher engages with the rear edge 17 of the cover, so that in this retraction it carries the rear edge of the cover with it, this rear edge moving away from the second focus F2 and the lens 4. It will be understood that if the actuator, the pusher and the cover were arranged so that the deformation of the cover was done by deploying the pusher, the free end of the pusher would not need to be in engagement with the cover but only in longitudinal stop.

The cover 6 is held at its ends on the housing 7, by means of the fixing means 23, so that the stress suffered by the rear edge of the cover generates not a longitudinal movement of the cover, but rather a deformation of the cover , mainly in its central reflection zone 10, taking the effect of a rotation substantially around an axis defined by the two fixing zones of the cover on the housing. In this way, the stress exerted by the deformation means 24 on the rear edge 17 results in a collapse of the cutting edge 18, according to the arrow T2 shown on the Figure 3 . We understand that the movements made are of low amplitude and that they were amplified on the Figure 3 to make the reading of the present invention clearer. Thus, we can see that the rear part of the upper face 14 of the cover remains in place, held by the fixing means 23 on the housing, while the lower end of the rear edge moves back and the cutting edge is sags. In practice, we obtain a slight modification, under the effect of the deformation, of the location of said cut-off edge 18 within the light module, and therefore a modification of the beam projected in an active position allowing the illumination of the panels located above the road scene.

We understand that this modification of the beam, due to a deformation of the cache, cannot be continuous over time. Here we only foresee point deformations, when the associated control module determines conditions appropriate to such deformation. In particular, the control module can send an instruction to the deformation means when it receives information, coming for example from a speed sensor, according to which the speed of the vehicle is greater than a determined threshold, and it will repeat this instruction at regular intervals as long as the speed is above this threshold.

In a variant illustrated on the Figure 4 , the deformation means 24 still comprise an actuator 26 and a pusher 28, but this is arranged in relation to the cover so that, contrary to what was said previously where the pusher acted on the rear edge 17 of the cover 6 in a direction substantially parallel to the optical axis, the pusher here abuts under the cover to act on the rear edge in a direction substantially perpendicular to the optical axis, in the direction T3 visible on the Figure 4 which is opposite to the desired direction of movement T2 of the cutting edge 18.

We now refer to the Figure 5 to now describe a second embodiment of the invention. The operating principle is the same as that previously cited, and the comments on the active and passive positions of the cache are to be applied to this second embodiment.

The deformation means 24 consist in this case of a piezoelectric actuator 30. An actuator of this type must be directly in contact with the cover. We could plan for it to be entirely placed on the cover 6, ensuring that it does not hinder the reflection of the beams reflected by the elliptical reflector 3, or we can choose an installation as illustrated in which the The piezoelectric actuator 30 is arranged astride the base 9 and the cover 6. As in the previous embodiment, the cover is at a distance from the base, so that it can deform freely, only retained by its means side fixings to the housing 7.

In the example illustrated on the Figure 5 , the actuator is attached to the side of the upper face of the base, opposite to what was described for the first embodiment. We understand that one or other of the solutions can be chosen, as long as we are careful not to hinder the propagation of the rays.

As just described, the invention makes it possible to obtain different light beam profiles, without it being necessary to implement complex means of moving the cover.

It further emerges from the above that the invention, by the implementation of simple means and reduced bulk (fixed cover 6 and deformation means 24), can easily be implemented on a wide variety of vehicles. and light modules used for lighting and/or signaling these vehicles.

It should of course be noted that the invention cannot be reduced to the means and configurations described and illustrated, but that it also applies to all equivalent means or configurations and to any combination of such means. In particular, the type of deformation means 24 of the cover 6 and the location of fixing of these deformation means are, in the preceding description, given by way of examples, and the exact nature of the deformation means used, as well as as their location, must be specified depending on the specific applications of the invention to obtain cutoff profiles other than those described in this document.

We also understand that the invention has just been described according to two embodiments in which the light module only comprises means for emitting a passing beam, but that it can be applied in modules where these means passing beam emission are combined with means for emitting a complementary beam to form a main beam when necessary.

Claims (10)

1. Light module (1), for lighting and/or signalling of a motor vehicle, comprising at least one light-emitting assembly (2), an elliptical reflector (3) of which a first focus is situated in the vicinity of the light-emitting assembly (2), convergent optical means (4) for focusing the beam emitted, a focal plane of which passes in the vicinity of the second focus of the elliptical reflector (3), and a housing (7) in which the light-emitting assembly (2), the elliptical reflector (3), and the convergent focusing means (4) are accommodated, said light module further comprising a cover (6) inserted, on the optical axis (8) of said light module, between the elliptical reflector (3) and the convergent focusing means (4) in such a way that a cut-off edge (18) of said cover (16) intercepts a part of the rays emitted by the light-emitting assembly (2) and deriving from a first reflection by the elliptical reflector (3), said cover (6) being fixed in said housing (7), the light module (1) comprising means (24) for deforming said cover (6) to modify the position of said cut-off edge (18) relative to the light-emitting assembly (2) and to the elliptical reflector (3),
   characterized in that the light module (1) comprises a base (9) on which is mounted the light-emitting assembly (2) and various control elements thereof, and in that the cover (6) consists of a plate which extends substantially parallel to the base (9), substantially horizontally.
2. Light module (1) according to Claim 1, characterized in that the cover comprises a central reflection zone (10) and end zones (12) extending on either side of said central zone.
3. Light module (1) according to either of Claims 1 and 2, characterized in that the deformation means (24) act on a rear edge (17) of the cover (6) opposite the cut-off edge (18).
4. Light module (1) according to any one of Claims 1 to 3, characterized in that the action of the deformation means (24) on the cover (6) is reflected by a slight translational or rotational displacement of at least a part of the cut-off edge (18).
5. Light module (1) according to one of the preceding claims, characterized in that the deformation means (24) are fixed to the base (9) on which is mounted at least the light-emitting assembly (2).
6. Light module (1) according to one or other of Claims 1 to 5, characterized in that the deformation means (24) are controlled by an actuator (26) controlling a pusher (28).
7. Light module (1) according to the preceding claim, characterized in that the deformation means (24) act on the rear edge (17) of the cover (6) in a direction substantially parallel to the optical axis.
8. Light module (1) according to Claim 6, characterized in that the deformation means (24) act on the rear edge (17) of the cover (6) in a direction substantially at right angles to the optical axis, in the direction opposite to the desired direction of displacement of the cut-off edge.
9. Light module (1) according to one or other of Claims 1 and 2, characterized in that the deformation means (24) comprise a piezoelectric actuator (30).
10. Light module (1) according to the preceding claim, characterized in that the piezoelectric actuator (30) is borne at least partially by the cover (6).

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