Motor vehicle lighting and/or signalling device

An optical module for a motor vehicle lighting and/or signaling device, having an optical deflection element, a support to which the optical deflection element is fixed, the support comprises adapter fixing means capable of fixing an adapter to which a light source is fixed, and wherein the first optical deflection element comprises adapter indexing means arranged so as to be capable of positioning this adapter relative to the first optical deflection element on two separate intersecting axes.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is the U.S. National Phase application of PCT Application No. PCT/EP2013/075006 filed on Nov. 28, 2013, which claims priority to the French application 1261524 filed on Nov. 30, 2012, which applications are incorporated herein by reference and made a part hereof.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a lighting and/or signaling device comprising, or intended to comprise, a light source adapter, particularly a light-emitting diode, intended to bear on the support of a first optical element of this module. It also relates to the corresponding adapter.

2. Description of the Related Art

Motor vehicle lighting and/or signaling devices, such as headlights and rear lights, consist of a housing sealed by a sealing lens and containing one or more optical modules. The light beams emitted by these devices are formed by the optical module or modules, which may operate in combination or separately. These optical modules comprise a light source associated with one or more optical deflection elements, and with shields if necessary, to modulate the shape of the beam and the distribution of the luminous intensity in this beam.

The document FR2950129 comprises an optical module using an LED, or light-emitting diode, wherein, in order to allow the control of the power supply to this LED the latter is placed on a printed circuit. The printed circuit on which the LED is fixed is fixed to an adapter which positions it in the optical module. This adapter enables the LED of this module to be changed by removing and replacing the adapter. In order to allow for the cooling of the LED, the adapter is thermally conductive and must be in contact with the radiator supporting the reflector over the greatest possible surface area. This demands major constraints on the manufacture of the adapter and of the radiator to precisely position the adapter.

One issue addressed by the present invention is to remedy this.

SUMMARY OF THE INVENTION

The invention therefore proposes a light source adapter, comprising:

at least one light source,

a support block on which the light source is directly or indirectly fixed, said support block being a radiator comprising fins and being arranged to dissipate the heat given off by this light source,

complementary fixing means suitable for enabling the adapter to be fixed.

The block can notably have the LED on one side and the fins on the other, notably on either side of a plate.

Thus, it will be possible to use an adapter making it possible to rapidly and directly cool the light source. The adapter will then be able to be positioned and fixed on narrower portions than in the prior art, notably by tenons, notches, on an optical element support having an aperture to allow these fins to pass through. The positioning of the adapter and of the module is thus simplified. This is particularly advantageous in the context of a replacement of the light source, above all if it is an LED.

The adapter can also comprise a printed circuit, on which the light source is fixed and connected.

According to an embodiment of the invention, the adapter also comprises:

a printed circuit, to which the light source is fixed and connected,

complementary fixing means capable of enabling the adapter to be fixed,

complementary indexing means formed on the printed circuit, arranged so that, when an element is positioned relative to these indexing means, the adapter is positioned relative to this element on two separate intersecting axes.

Thus it will be possible to index this adapter precisely relative to these indexing means, particularly with a module according to the invention. This is particularly useful in the context of replacement of the light source, since this replacement can be carried out on the vehicle.

It also makes it possible to have an adapter carrying a standard light source that can be adapted to different types of optical modules. This adapter can be designed for LEDs, which is even more advantageous. This is because an LED is an electronic component, and in many designs of optical modules the failure of the LED requires the replacement of the whole module, or even of the lighting and/or signaling device. Thanks to the invention, it is possible to replace a smaller part of the module, namely the adapter and its light source. Thus the cost of replacement is reduced.

It should be noted that this printed circuit may be a printed circuit card, and the adapter may comprise a support unit, for example a radiator, on which the printed circuit is fixed. This circuit may also be directly formed or printed on the support unit, which, in this case also, may be a radiator. The support unit may comprise fins.

The adapter according to the invention may also have, in addition to the main characteristics stated in the preceding paragraphs, one or more of the following complementary characteristics:

the complementary indexing means are apertures; this is a simple means of construction;

the apertures are holes passing through the printed circuit from one side to the other; in this way the positioning is reinforced;

the adapter comprises a support unit on which the printed circuit is fixed, the support unit comprising cavities facing the through holes, each through hole opening entirely into its own cavity; this provides a greater tolerance on the length of the indexing means of the various types of module on which the adapter can be mounted;

the adapter comprises a metal rod pivoted at one end on the adapter, the rod further comprising a fixing part to be fixed to an element such as an optical module, the rod being arranged to allow compression fixing of the adapter to this element;

the pivot comprises a through hole in which an end of the metal rod is freely rotatable;

the pivot is arranged on a fin of the adapter, or on a projecting part separate from the fins of the adapter;

the metal rod comprises a portion capable of interacting with an indentation;

the metal rod comprises a graspable portion in the form of a loop intended to be gripped to enable the rod to be detached;

the rod is in the form of a loop, which may or may not be closed, and which is pivoted at one end and has a portion capable of interacting with an indentation at the other end;

the adapter comprises a connector connected to the light source and capable of being connected to an electrical power source to supply the light source.

The invention also proposes an optical module for a motor vehicle lighting and/or signaling device comprising:

a first optical deflection element,

a support of this optical deflection element, the first optical deflection element being fixed to the support,

wherein the support comprises adapter fixing means;

an adapter according to the invention fixed to the support of this optical deflection element via the adapter fixing means,

This optical module can notably be an optical module for a motor vehicle lighting and/or signaling device comprising:

a first optical deflection element,

a support for this optical deflection element, the first optical deflection element being fixed to the support,

in which the support comprises adapter fixing means fixing the adapter on which the light source is fixed or receiving a fixing element of this adapter, and in which the first optical deflection element comprises adapter indexing means arranged so as to position this adapter relative to the first optical deflection element according to two distinct and secant axes.

Thus this module will be capable of receiving an adapter which is to be indexed directly on the optical element, also called the optical deflection element in the present application, at least on two separate intersecting axes. By comparison with the prior art, the present applicant might have attempted to improve the precision of machining or manufacture of the elements, and to position them even more precisely during assembly. In his inventive activity, the applicant has taken a different approach and found a solution enabling him to decrease his tolerance stack-up, which, notably in view of the examples disclosed in the prior art, notably in view of FR2950129, is not evident. The applicant has dispensed with the indexing on the element support taught by the prior art, and has discovered means of directly indexing the light source on the optical element on at least two axes. In this way a reduced tolerance stack-up on these two axes is achieved, as well as greater precision. It should be noted that this advantage is obtained while the fixing of the optical element to the support is retained, allowing forces to be exerted on the support, rather than directly on the optical deflection element, during the dismounting of the adapter. This is particularly appropriate for the replacement of the light source, notably in the case of an LED.

The optical module according to the invention may also have, in addition to the main characteristics stated in the preceding paragraphs, one or more of the following complementary characteristics:

the optical deflection element may be, notably, a reflector, an optical lens, or a light guide.

the indexing means of the support comprise apertures and/or studs; this enables an adapter having complementary shapes to be positioned and indexed by simple movements; these means are also easy to provide;

the support of the optical deflection element is a heat sink, and comprises:a material capable of conducting heat,contact surfaces comprising part of this material, such as to transmit the heat of an element that may be in contact with the contact surfaces;
this support may also be capable of acting as a heat sink for the adapter to be mounted thereon, and in particular of directly dissipating the heat given off by the light source fixed to the adapter; the support may comprise fins, in which case the support is a finned radiator;

the support may comprise rear fins located at the rear of the support and behind the optical deflection element relative to the direction of propagation along which the optical deflection element is intended to deflect the rays; this enables the heat to be removed toward the rear, once the module has been mounted inside a lighting and/or deflection device; furthermore, the exchange surface is increased without hindrance on the path of the light rays emitted by the source and deflected by the optical deflection element;

the rear fins comprise a discontinuity arranged so as to form a space free of fins, in which at least a part of the adapter fixing means is located; in this way the compactness of the system is improved;

the support also comprises a connector intended to be connected, on the one hand, to the electrical power supply of a vehicle, and on the other hand to the light source, the connector being housed in the space free of fins;

the support is L-shaped and comprises:the rear fins on a first branch of the L-shape,if necessary, other fins, on a second branch of the L-shape;
this makes it possible to have a simple design for the distribution of the fins, the optical deflection element being mountable, for example, between the branches of the L-shape to improve heat dissipation;

the adapter fixing means, that is to say the means intended to fix the adapter to the module, comprise at least one lug with at least one indentation capable of receiving a metal fixing rod; this is a simple means of fixing; the use of the rod for fixing enables the parts to be pressed against one another, using the spring action of the rod;

the adapter fixing means comprise another indentation capable of receiving a metal fixing rod, in such a way that each indentation defines a different fixing position of the metal rod; this enables a pre-positioning of an adapter to be defined during its replacement;

the support comprises a metal rod pivoted at one end on the support, the rod further comprising a fixing part intended to be fixed to the adapter, the rod being arranged to allow compression fixing to module; thus a simple means of attachment is provided, avoiding the use of screws which would require the use of a screwdriver during replacement; additionally, during the replacement of the light source and its adapter, there is no risk that this fixing means might fall into the lighting and/or signaling device in which the module is mounted;

according to a simple embodiment, the pivot comprises a through hole in which an end of the metal rod (190;290) is freely rotatable;

the pivot is arranged on a fin of said optical deflection element support, or on a projecting part separate from the fins; this pivot is simple to produce;

the metal rod comprises an attachment part capable of interacting with an indentation of the adapter fixing means; the fixing can thus be carried out easily in a single movement, thereby facilitating the replacement of the adapter, this being all the more advantageous in that access to the lighting and/or signaling device is sometimes difficult in a vehicle;

the metal rod comprises a graspable portion in the form of a loop intended to be gripped to enable the rod to be detached from the adapter fixing means;

the rod is in the form of a loop, which may or may not be closed, and which is pivoted at one end and fixed to the adapter fixing means at the other end;

the support comprises:an opening facing the optical deflection element,guide fins on either side of this opening, notably parallel with one another,bearing surfaces between this opening and these guide fins, the guide fins being arranged so as to allow the guiding of a unit having a width close to the distance between these guide fins, to position the unit in contact with these bearing surfaces; thus, if the adapter is a unit of this type, it can be made to slide even when module is difficult to access and/or if it is invisible or poorly visible; the bearing surfaces may be the contact surfaces mentioned previously;

the contact surfaces are covered by a compressible heat-conducting element, notably a filled silicone; this enables the compressible element to be compressed until the adapter touches the optical deflection element and is then indexed on a third axis, not on the support, the adapter thus being indexed directly on the optical deflection element in all directions in space.

at least one light source fixed directly or indirectly to the adapter and emitting light rays toward the first optical deflection element, the support being arranged to allow the passage of these light rays, the adapter comprising complementary indexing means interacting with the adapter indexing means so that the adapter and the first optical deflection element are positioned on two separate intersecting axes relative to one another.

The optical module according to the invention may also have, in addition to the main characteristics stated in the preceding paragraphs, one or more of the following complementary characteristics:

the adapter indexing means are apertures, wherein the complementary indexing means are a shape complementary to the shape of this aperture and are housed within this aperture;

the complementary adapter indexing means are apertures, wherein the adapter indexing means have a shape complementary to the shape of these apertures and are housed within these apertures;

the adapter comprises complementary fixing means interacting with the adapter fixing means which are carried by the support;these complementary fixing means or these adapter fixing means comprise a spring integral with the support and with the adapter, arranged so as to press the support against the adapter; this spring may be a metal rod;

the adapter is an adapter proposed by the invention, as described previously;

the support comprises a projecting toothlike part housed between two fins of the adapter; this tooth may be designed with a clearance, in which case it acts solely as a guide means during replacement; the adapter may also bear against this tooth, in which case it also acts as a means for fixing the adapter;

the support comprises a projecting toothlike part, the projecting part comprising the pivot of a metal rod for fixing the adapter to the adapter fixing means;

a metal rod is pivoted at one end to the support, and an attachment part of the rod is attached to an adapter fixing means carried by the support, the rod comprising a pressing portion located between the pivoted end and the attachment part, the pressing portion bearing against the adapter so as to press the latter against the support; this is a simple fixing method enabling the elastic or spring action of the rod to be used to fix the adapter to the module by a single swinging and attachment movement;

the adapter has contact surfaces pressed into direct or indirect contact with contact surfaces of the support; the retention is secure; in order to reinforce the retention further, these contact surfaces may be flat;

the optical module comprises a compressible heat-conducting element, notably a filled silicone, located between these contact surfaces;

the adapter being in direct contact with the optical deflection element, so that the adapter is indexed relative to the optical deflection element on another axis, separate from the other two axes; the adapter being thus indexed directly on the optical deflection element in all the directions of space;

these contact surfaces are in direct or indirect thermal contact, so that the adapter and the support of the optical deflection element form a single heat sink; module is particularly effective because the heat dissipation takes place as closely as possible to the base of the light source, which is even more advantageous when the light source is an LED;

the single heat sink comprises fins, some of which are located on the adapter, while the others are located on the support;

the adapter comprises a connector connected to the light source, and wherein the support also comprises a connector, one of the connectors being plugged into the other; the arrangement of the two connectors can thus be such that the connectors are plugged in directly when the adapter is positioned and fixed.

In the optical modules and the adapters according to the invention, the adapter may comprise a plurality of light sources.

The present invention applies also to optical modules suitable for receiving an adapter according to the invention, notably when the adapter is not mounted on top. These modules can have the features of the modules previously described.

In the optical modules and the adapters according to the invention, the light source or sources may be one or more light-emitting diodes. The modules according to the invention are particularly suitable for LEDs, because:

they allow the LEDs to be replaced in restricted spaces,

they allow precise positioning of the LED relative to the optical element,

the reflector fixing exerts less stress on this optical element, the fixing being made to a support which is separate from the optical element,

according to the variant embodiments, they allow good thermal removal of the heat given off by the LED or LEDs.

Another object of the invention is a vehicle lighting and/or signaling device comprising a module according to the invention. For example, the device may be a headlight, also called a vehicle headlamp.

The optical module may be a lighting module, for example in order to provide an illuminating beam or a low beam.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

The various elements appearing in more than one figure are given the same reference numerals, unless stated otherwise. Elements appearing in more than one figure will not be newly described in full or mentioned for every figure.

FIGS. 1 to 12show three embodiments according to the invention. These illustrations are exemplary embodiments.

The optical module10,110and210for a motor vehicle lighting and/or signaling device according to the invention comprises:

a first optical deflection element12, which in the case of these examples is a reflector12,

a support20,120and220of the reflector12, the reflector12being fixed to the support20,120and220, wherein the support20,120and220comprises adapter fixing means26,126and226capable of fixing an adapter to which a light source is fixed, or of receiving a fixing element of this adapter, and wherein the reflector12comprises adapter indexing means61,62arranged so as to be capable of positioning this adapter relative to the reflector12according to two separate intersecting axes X, Y.

According to these embodiments, the indexing means61,62, shown inFIGS. 3 and 6are studs61,62.

The support20,120and220is a heat sink, and comprises:

a material capable of conducting heat,

contact surfaces66comprising part of this material, such as to transmit the heat of an element that may be in contact with the contact surfaces, for example the contact surfaces76of the adapter70shown inFIG. 4.

In general, the support20,120and220may be a monolithic material, for example by being made of one piece of material. It may essentially consist of the material capable of conducting heat. The material capable of conducting heat may be metal, notably aluminum.

As illustrated, the support20,120and220comprises rear fins24and25, or124and125, located at the rear of the support20,120and220and behind the optical deflection element12relative to the direction of propagation R along which the optical deflection element12is intended to deflect the rays. The direction of propagation R is shown inFIG. 1only, but is the same in the various figures. This support20,120and220therefore forms a finned radiator24and25, or124and125.

The support20,120and220comprises:

guide fins23,123on either side of this opening29, notably parallel with one another,

bearing surfaces66between this opening29and these guide fins23,123, the guide fins23,123being arranged so as to allow the adapter70,170,270to be guided in order to position it in contact with these bearing surfaces66.

In fact, as can be seen inFIGS. 5 and 6, the adapter70,170,270according to the invention has a width less than, but close to, the distance between these guide fins23,123, which facilitates guiding and positioning during the replacement of the adapter70,170,270.

According to the illustrated examples, these bearing surfaces66are the contact surfaces. Consequently they have the double function of providing thermal and mechanical contact.

In these examples, the optical module is a lighting module, for example in order to provide an illuminating beam, for example a low beam.

The adapter70,170,270is designed at the position of the opening29in such a way that the light source13fixed above has its general direction of emission orientated toward the concavity of the reflector12. The latter reflects the light rays emitted by the light source13along the direction of propagation R, parallel to the longitudinal axis X, in the illustrated examples, the direction of propagation R parallel to the longitudinal axis X defining the forward direction in this case. The light source13provides downward illumination.

The support20,120and220comprises in this case two plates joined in the general shape of an “L”, at about 90° for example, and comprises:

on a first branch of the L-shape located behind the module, the rear fins24and25,124and125,

on a second branch of the L-shape, the guide fins23.

The second branch may comprise other fins which are not shown.

The rear fins25,125comprise a discontinuity25a,125aarranged so as to form a space free of fins27,127, in which is located at least a part of the adapter fixing means26,126,226, in this case pairs of toothlike lugs. Each lug comprises at least one indentation capable of receiving a metal fixing rod90,190,290of the adapter70,170,270.

In these exemplary embodiments, the adapter70;170;270of the light source13comprises:

at least one light source13,

a printed circuit80, to which the light source13is fixed and connected,

complementary fixing means or rod90,177or277, capable of enabling the adapter70,170,270to be fixed,

complementary indexing means71,72formed on the printed circuit80, arranged so that, when an element is positioned on the optical module relative to these complementary indexing means71,72, the adapter70,170,270is positioned relative to this element on two separate intersecting axes, in this case the longitudinal axis X and the transverse axis Y.

These complementary indexing means are apertures71,72, particularly holes passing through the printed circuit80from one side to the other.

The adapter70,170,270of the light source13comprises a support unit73to which the printed circuit80, and therefore indirectly the light source13, is fixed and connected.

As can be seen more precisely inFIG. 4, the light source13is an LED comprising a substrate15fixed to the printed circuit80, by electrodes for example. The substrate15carries a photoemissive semiconductor element14.

The support unit73is a radiator comprising:

fins75,175and275, and being arranged to dissipate the heat given off by this light source,

complementary fixing means90,177or277, capable of enabling the adapter70,170,270to be fixed.

According to the invention, in general the adapter70,170,270or the support may carry a pivoted metal rod90,190,290which is made to be attached to or pressed against the support or the adapter70,170,270respectively.

Thus, according to the first embodiment shown inFIGS. 1 to 6, the fins75of the edges of the adapter70comprise a hole64(FIG. 4) through which the end93of a rod90passes. The end93of the metal rod90is freely rotatable in this hole64, so as to form a pivot of the rod90on these two fins75. The rod90is made in the shape of a loop which is not closed. Two ends93are therefore pivoted. The loop can thus swing downward to be attached to the adapter fixing lugs26formed on the support20, the attached portion of the loop thus forming a fixing part91.

The support73comprises a toothlike projecting guiding and retaining part22(FIGS. 1, 3 and 5).

As shown inFIGS. 5, 6 and 6′, when the adapter70is placed in module10, the adapter70slides on the contact surfaces66of the support20, being guided transversely by the guide fins23of the support20. It will slide until it is blocked by the projecting lug22, which becomes housed between two fins75of the adapter70, thus completing the guiding. The adapter70can then be lowered so that its contact surfaces76, located on either side of the printed circuit, come into contact with the contact surfaces66of the module.

The studs61,62will enter the through holes71,72, and index the LED13relative to the reflector12, notably at the position of its focus.

As can be seen inFIG. 6′, the support unit comprises cavities74facing the through holes71, each through hole opening entirely into its own cavity74. The studs71pass through the printed circuit into these cavities. Consequently they do not have to be designed exactly to match the size of the holes in the printed circuit.

When the adapter70has been positioned and pressed against the support20, the rod90is lowered toward the rear branch of the L-shape of the support20, and becomes attached to the adapter fixing lugs26.

The adapter70is thus kept pressed against the support20by the rod90on the one hand, and by the lug22on the other hand.

In the other embodiments, the principle of the mounting of the adapter170,270is generally the same, but with the differences described below.

The metal rod190,290is pivoted at one end on the support120,220, the rod further comprising a pressing part195,295, to be fixed by pressing to the adapter170,270, the rod190,290being arranged to allow compression fixing of the adapter170,270to the module, by bearing on the bearing surfaces177,277of the adapter170,270.

In the second embodiment, the through hole in which the end193of the rod190,290is pivoted is arranged on a fin123(FIG. 7) of the support120of the reflector12.

In the third embodiment, the through hole in which the end293of the rod190,290is pivoted is arranged on a projecting part222(FIG. 9) separate from the fins123.

In these various embodiments, the metal rod90,190,290comprises an attachment part91,191,291that is made to interact with an indentation26a,126a,226aof the adapter fixing means26,126,226.

The metal rod90,190,290comprises a graspable portion94,194,294in the form of a loop intended to be gripped to enable the rod90,190,290to be detached from the adapter fixing means26,126,226, for example by being grasped by an operator's finger.

In the second embodiment and in the third embodiment, the pressing portion195,295is located between the attachment part191,291and the pivoted end193,293. Thus the adapter170,270is kept pressed against the support120,220by the attachment of the attachment part191,291on the one hand, and by the fixing part195,295on the other hand.

In the second embodiment, the adapter fixing means126comprise another indentation126bcapable of receiving the metal fixing rod190, in such a way that each indentation126a,126bdefines a different fixing position of the metal rod190. Thus, as shown inFIG. 7, the rod190is positioned in the intermediate indentation126b, allowing the module to be pre-positioned before its final fixing, for example in order to adjust it correctly before it is lowered. The rod190is then placed in the final indentation126ato fix the adapter170finally in the support120. Clearly, the term “final” is to be interpreted as meaning “final for the purpose of making the module operable”, rather than final for the whole service life of the module, since according to the invention this attachment is removable to allow the light source to be replaced by the withdrawal and replacement of the adapter.

As may be seen, according to the invention the support unit comprises by the adapter70,170,270is a radiator whose fins75,175,275are arranged to dissipate the heat given off by the LED13. This is even more effective because they are orientated upwards.

In the three embodiments, the adapter70,170,270comprises a connector82,182or282connected to the LED13, and the support20,120and220also comprises a connector82,182.

As shown inFIG. 10, according to the invention, these connectors82,182are arranged one above the other when the adapter70is positioned in the support20,120,220, so that, during assembly, the simple fact of lowering the adapter70,170,270onto the module causes the connectors82,182to be plugged into one another.

As shown inFIG. 11, the connector382of the adapter70may comprise connecting pins384,385, the connector502of the support20being electrically connected by the insertion of its pins504,404between those of the connector of the adapter70.

As shown inFIG. 12, the pins of the connector of the support20comprise blades516mounted on more rigid parts514between which the central pin of the connector of the adapter70is inserted, the rigid parts514being housed between the walls484of the connector of the adapter70. The rigid parts514are connected to the support20by means of a spring518enabling the dimensional tolerances to be reduced for mounting during the fixing of the adapter70.

According to one embodiment, the contact surfaces76of the adapter70and of the support20are in direct contact. The optical element have a clearance on an axis perpendicular to the tangent to these contact surfaces76, that is to say on the vertical axis Z in the illustrated embodiments. Thus on this axis the arrangement is made according to the support20. This clearance may, for example, be in the range from 0.1 to 2 mm, preferably from 0.5 to 1 mm, or preferably 0.5 mm.

According to a variant embodiment, the contact surfaces66of the support20and/or the contact surfaces76of the adapter are covered with a compressible heat-conducting element, notably a filled silicone, for example a PAD900silicone. This compressible element may have a thickness of about 229 μm. The adapter is in direct contact with the optical deflection element12, in such a way that the adapter70,170,270is indexed relative to the optical deflection element12on the vertical axis Z.

It can be seen here that, in three embodiments, the contact surfaces66and76are in direct or indirect thermal contact, so that the adapter70,170,270and the support20,120,220of the optical deflection element12form a single heat sink, the fins being located in some cases (75,23,24,25;175,123,124,125;275,223,224,225) on the adapter70,170,270, and in other cases on the support20,120,220.

This provides a radiator enabling heat to be removed directly from the base of the LED13, and an extensive exchange surface.

While the system, apparatus, process and method herein described constitute preferred embodiments of this invention, it is to be understood that the invention is not limited to this precise system, apparatus, process and method, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.