FR3063048A1 - LUMINOUS DEVICE FOR MOTOR VEHICLE - Google Patents

Abstract

The invention relates to a lighting device (10) for a motor vehicle comprising: - a housing (3); - a printed circuit board (5) housed in the casing (3) and comprising a first face (5A) and a second face (5B); - a light source (7) disposed on said first face (5A) of the printed circuit board (5); - a control module (9) of the light source (7); - a heat sink (13), said heat sink (13) being in contact with said second face (5B) of the printed circuit board (5) opposite to said first face (5A) of said printed circuit board (5) carrying said light source (7).

Description

(54) LIGHT DEVICE FOR A MOTOR VEHICLE.

FR 3,063,048 - A1 (57) The invention relates to a light device (10) for a motor vehicle comprising:

- a housing (3);

- a printed circuit board (5) housed in the housing (3) and comprising a first face (5A) and a second face (5B);

- a light source (7) disposed on said first face (5A) of the printed circuit board (5);

- a control module (9) of the light source (7);

- a heat sink (13), said heat sink (13) being in contact with said second face (5B) of the printed circuit board (5) opposite to said first face (5A) of said printed circuit board (5) carrying said light source (7).

LIGHT DEVICE FOR A MOTOR VEHICLE

TECHNICAL FIELD OF THE INVENTION

The present invention relates to a light device for a motor vehicle.

TECHNOLOGICAL BACKGROUND OF THE INVENTION

A light device for a motor vehicle comprises, in a manner known to a person skilled in the art:

- a housing ;

- a printed circuit board housed in the housing;

- a light source disposed on said printed circuit board;

- a light source control module.

In order to optimize the space taken up by these lighting devices in the passenger compartment, their size is reduced. Due to this small footprint, the light source is very close to the control module on the printed circuit board. However, this control module is a non-negligible source of heat which can impact the operation of the light source, and ultimately degrade its optical performance.

In this context, the present invention aims to solve the drawbacks mentioned above.

GENERAL DESCRIPTION OF THE INVENTION

To this end, the invention provides a light device for a motor vehicle comprising:

- a housing ;

- a printed circuit board housed in the housing and comprising a first face and a second face;

- a light source disposed on said first face of the printed circuit board;

- a light source control module;

a heat sink, said heat sink being in contact with said second face of the printed circuit card opposite to said first face of said printed circuit card carrying said light source.

Thus, as will be seen in detail below, the heat sink is in contact with one face of the printed circuit card and disposed below the light source and the control module. This heat sink is thus adapted to dissipate the heat released by the components of the printed circuit board, in particular by the control module, so that it cannot impact the operation of the light source disposed on said circuit board. printed.

According to non-limiting embodiments, the light device can also include one or more additional characteristics among the following:

According to a nonlimiting embodiment, part of the heat sink extends outside the housing.

According to a nonlimiting embodiment, the heat sink is metallic or made of thermally conductive plastic

According to a nonlimiting embodiment, the heat sink comprises a main part and two secondary parts extending from the main part so that said heat sink has a U-shaped section.

According to a nonlimiting embodiment, the secondary parts are directed towards a lower part of the housing.

According to a nonlimiting embodiment, the secondary parts are directed towards an upper part of the housing so as to frame the printed circuit board.

According to a nonlimiting embodiment, the housing has a lower part comprising a notch adapted to receive said heat sink.

According to a nonlimiting embodiment, the housing has a lower part comprising a light adapted to accommodate said heat sink.

According to a nonlimiting embodiment, the heat sink comprises a main part and two secondary parts framing the main part so that said heat sink has an H-shaped section.

According to a nonlimiting embodiment, said light device comprises means for fixing the heat sink to said housing, said fixing means comprising, at least:

- a clip, said clip belonging to said housing;

- A notch adapted to receive said clip, said notch belonging to said heat sink.

According to a nonlimiting embodiment, the heat sink comprises two nested folds.

According to a nonlimiting embodiment, the two nested folds comprise:

- a common base part; and

- respective secondary parts which are superimposed between them.

According to a nonlimiting embodiment, at least one of the folds comprises a plurality of fins.

According to a nonlimiting embodiment, the housing is opaque.

According to a nonlimiting embodiment, the light source is a semiconductor emitting chip.

According to a nonlimiting embodiment, the semiconductor emitting chip is part of a light emitting diode.

According to a nonlimiting embodiment, the light source is an RGB light source.

According to a nonlimiting embodiment, the heat sink is glued to the second face of the printed circuit card or in contact with the second face of the printed circuit card via a thermal interface.

According to a nonlimiting embodiment, the base part and the part which is closest to the base part define a first space adapted to receive the lower part of the housing. This allows the lower part of the housing to be inserted into this first space.

According to a nonlimiting embodiment, the two superimposed parts delimit a second space through which an air flow can pass.

According to a nonlimiting embodiment, the heat sink is made of a thermally conductive material.

BRIEF DESCRIPTION OF THE FIGURES

The invention and its various applications will be better understood on reading the description which follows and on examining the figures which accompany it.

- Figure 1 shows an exploded view of a light device for a motor vehicle according to a first non-limiting variant of a first non-limiting embodiment of the invention, in which the light device comprises a heat sink having a shaped section of U;

- Figure 2 shows an assembled perspective view of the light device of Figure 1;

- Figure 3 shows a sectional view of the light device of Figure 1 and Figure 2;

- Figure 4 shows an exploded view of a light device for a motor vehicle according to a second non-limiting variant of a first non-limiting embodiment of the invention, in which the light device comprises a heat sink having a shaped section of U;

- Figure 5 shows a sectional view of the light device of Figure 4;

- Figure 6 shows a first non-limiting embodiment of means for hooking the heat sink on a housing of the light device of Figure 4;

- Figure 7 shows a second non-limiting embodiment of means for attaching the heat sink to a housing of the light device of Figure 4;

- Figure 8 shows an exploded view of a light device for a motor vehicle according to a third non-limiting variant of a first non-limiting embodiment of the invention, in which the light device comprises a heat sink having a shaped section of U;

- Figure 9 shows a sectional view of the light device of Figure 8;

- Figure 10 shows an exploded view of a light device for a motor vehicle according to a second non-limiting embodiment of the invention, wherein the light device comprises a heat sink having an H-shaped section;

- Figure 11 shows an assembled perspective view of the light device of Figure 10;

- Figure 12 shows a sectional view of the light device of Figure 10 and Figure 11;

- Figure 13 shows an exploded view of a light device for a motor vehicle according to a first non-limiting variant of a third non-limiting embodiment of the invention, in which the light device comprises a heat sink comprising two nested folds;

- Figure 14 is a zoom on the heat sink of Figure 13;

- Figure 15 shows a sectional view of a light device of Figure 13 according to a first alternative embodiment, in which the light device comprises a closed housing;

- Figure 16 shows a sectional view of a light device of Figure 13 according to a second alternative embodiment, in which said the light device comprises a partially open housing;

- Figure 17 shows an exploded view of a light device for a motor vehicle according to a second non-limiting variant of a third non-limiting embodiment of the invention, in which the light device comprises a heat sink comprising two nested folds;

- Figure 18 is a zoom on the heat sink of Figure 17; and

- Figure 19 shows a sectional view of the light device of Figure 17.

DESCRIPTION OF EMBODIMENTS OF THE INVENTION

The identical elements, by structure or by function, appearing in the different figures keep, unless otherwise specified, the same references.

The light device 10 for a motor vehicle according to the invention is described with reference to Figures 1 to 19.

By motor vehicle is meant any type of motor vehicle.

In a nonlimiting embodiment, the light device 10 is suitable for a passenger compartment for a motor vehicle. This nonlimiting embodiment is taken in the following description.

Thus, in limiting examples, the light device 10 is a light device for:

- the doors of the motor vehicle;

- the overhead light of the motor vehicle;

- the dashboard of the motor vehicle;

- the center console of the motor vehicle;

- an area located under a seat of the motor vehicle, in or under the glove compartment or a storage compartment, etc.

To this end, the light device 10 is integrated into these different elements, for example in fittings of these different elements.

In a non-limiting embodiment taken in the following description, the light device 10 is a device for interior lighting of motor vehicle doors.

The light device 10 comprises:

- a housing 3;

- a printed circuit board 5;

- a light source 7;

- a control module 9;

- a heat sink 13.

The light device 10 further comprises electrical connection means 11.

The various elements of the light device 10 are described in detail below.

o Housing

The box 3 keeps the various parts of the light device 10 assembled. It also makes it possible to protect the printed circuit board 5 and the electronic components placed on said printed circuit board 5 such as the light source 7 and the control module 9 .

In the nonlimiting embodiments illustrated in FIGS. 1 to 19, the housing comprises an upper part 3A and a lower part 3B. The upper part 3A fits with the lower part 3B to form the housing 3 as a whole. The upper part 3A of the housing and the lower part 3B of the housing are made of a plastic material.

The upper part 3A covers the printed circuit card 5, while the lower part 3B is placed under the printed circuit card 5 on the side of the second face 5B not comprising electronic components. The lower part 3B enables said housing 3 to be closed.

The housing 3 has a reduced size which allows it to be discreetly housed in the passenger compartment of the vehicle. In a nonlimiting embodiment, the length of the housing is less than or equal to 48 mm, its width is less than or equal to 19.2 mm and its height is less than or equal to 20.4 mm. The upper part 3A of the housing and the lower part 3B of the housing have a wall which delimits an internal space in which the various elements of the light device 10 are housed.

In a nonlimiting embodiment, the housing 3 is opaque. This is to prevent light leakage which may be visible to a user of the motor vehicle.

In a nonlimiting embodiment, the housing 3 is adapted to fix a light guide (not illustrated) coupled to said light source 7.

To this end, in a nonlimiting embodiment, the housing 3 comprises a fixing module 8 for a light guide.

As illustrated in FIGS. 1, 4, 8, 10, 13 and 17, in a nonlimiting variant, the box 3 comprises:

- A reception area 8A of the light guide disposed on the upper part 3A of the housing 3. This reception area 8A comprises an opening 8D to let the light guide pass. In a nonlimiting embodiment, this zone has a substantially cylindrical shape;

- A slot 8B extending vertically from the opening 8D of the reception area 8A towards the upper part of the housing 3A;

- A locking notch 8C extending substantially perpendicular to the slot 8B at the end of said slot 8B opposite the end located at the opening 8D.

The light guide has a protrusion or pin adapted to fit into the blocking notch 8C of the housing 3. It is thus fixed on the upper part 3A of the housing 3. Thus, the locking of the light guide on the housing 3 is carried out by turning the light guide a quarter of a turn after its insertion into the reception area 8A, so that the pin of said light guide inserts into the locking notch 8C.

In another non-limiting alternative embodiment (not shown), the housing 3 comprises elastic means for fixing the light guide. In a nonlimiting example, these elastic fixing means are a clip adapted to pinch said light guide.

In a first nonlimiting embodiment, the lower part 3B of the housing 3 comprises a notch 15 adapted to receive the heat sink 13 as illustrated in FIGS. 1,8, 10, 13, 17.

In a second nonlimiting embodiment, the lower part 3B of the housing 3 includes a light 25 adapted to receive the heat sink 13 as illustrated in FIG. 4.

o Map. to circu.it i m p ri m é

The printed circuit board 5 is illustrated in FIGS. 1,4, 8, 10, 13 and 17.

The printed circuit board 5 also called PCB (“Printed Circuit Board” in English) supports the various electronic components of the light device 10.

It thus has a first face 5A and a second face 5B opposite the first face 5A.

The first face 5A receives the various electronic components. In particular, the light source 7 and the control module 9 are arranged on the first face 5A of the printed circuit board 5. The first face 5A also receives other electronic components necessary for the proper functioning of the light source 7 and the control module 9.

The second face 5B receives the heat sink 13 adapted to dissipate the heat produced by these various electronic components outside the printed circuit board and outside the housing 3.

The printed circuit board 5 has a relatively small size. In a nonlimiting embodiment, the thickness of the printed circuit board 5 is less than 1.6 mm.

ίο o Spurçejumineuse

The light source 7 is adapted to emit a light ray. The power of the light beam is relatively low. This power is sufficient for the desired interior lighting. In a nonlimiting embodiment, this power of the light ray is less than or equal to 5 lumens. In a nonlimiting example, the light ray is equal to 3 lumens.

It will be noted that the power of the light ray is a function of the temperature. Indeed, at a high temperature, the power decreases. The light source 7 thus loses efficiency and its light ray is weaker. It is therefore necessary to cool the light source 7 to prevent the power from decreasing too much.

In a nonlimiting embodiment, the light source 7 is a semiconductor emitting chip.

In a nonlimiting variant embodiment, the semiconductor emitting chip is part of a light-emitting diode. By light-emitting diode is meant any type of light-emitting diode, whether in non-limiting examples of LEDs (“Light Emitting Diode”), an OLED (“Organic LED”) or an AMOLED (“Active-MatrixOrganic LED”), or a FOLED ("Flexible OLED").

In a nonlimiting embodiment, the light source 7 is an RGB light source.

In the embodiments illustrated in FIGS. 1, 4, 8, 10, 13, 17, the light source 7 is coupled with a light guide (not shown). Thus, the light ray of the light source 7 propagates in the light guide.

o Depilotape module

The control module 9 (called in English "driver") is suitable for sending control commands to the light source 7 and for supplying it.

Note that the control module 9, by its operation, generates heat. It is thus necessary to cool it if we do not want the accumulation of heat in the housing 3 to degrade the light source 7 or the control module 9 itself which could lead to a total loss of the control function for example.

In a nonlimiting embodiment, the control module 9 comprises a microcontroller and / or a plurality of switches such as in a nonlimiting example of MOSFETs. Since such a control module is known to those skilled in the art, it is not described here.

o Connection means, electrical

The electrical connection means 11 are electrical contacts adapted to come into contact with a connector (not shown) so as to establish a connection.

The connector is connected to a power supply harness to connect to a power supply network of the motor vehicle. The electrical supply harness thus makes it possible to convey the supply voltage which comes from an electrical supply network such as a motor vehicle battery V and thus to supply the control module 9 via the electrical connection means. 11. The electrical connection means 11 are also suitable for conveying commands from an engine control unit ECU (called "Electronic Control Unit") to the control module 9 via the connector (not illustrated).

o Heat sink.

The heat sink 13 is adapted to dissipate the heat given off by the components of the printed circuit board 5.

This heat sink 13 is in contact with the second face 5B of the printed circuit card 5 opposite to the first face 5A of this same printed circuit card 5.

In a first non-limiting embodiment illustrated in Figures 1, 8 10 and 13 and 17, the heat sink 13 rests on the lower part 3B of the housing. It is thus sandwiched in part between the printed circuit board 5 and the lower part 3B of the housing. In particular its main part 13A (described below) rests on the notch 15 (described above) of the lower part 3B.

In a second nonlimiting embodiment illustrated in FIG. 4, the heat sink 13 is inserted in the lower part 3B of the housing 3. In particular, its main part 13A (described below) is inserted in the light 25 ( described above) of the lower part 3B.

The upper part 3A covers the printed circuit card 5. The box 3 therefore makes it possible to maintain in a relatively small space, the other elements of the light device 10, such as the printed circuit card 5 and in part the heat sink 13.

The lower part 3B makes it possible to close the box 3.

In a nonlimiting embodiment, the heat sink 13 is glued to the second face 5B of the printed circuit board 5.

In another nonlimiting embodiment, the heat sink 13 is in contact with the second face 5B of the printed circuit board 5B via a thermal interface. The latter can be glued or not. This thermal interface allows better heat transmission between the printed circuit board 5 and the heat sink 13.

As illustrated in FIGS. 1, 4, 8, 10, 13, 17, part of the heat sink 13 extends outside the housing 3. Thus, it makes it possible to bring the heat from inside the housing 3 to the outside of the housing 3 and thus to evacuate heat from the printed circuit board 5.

In a nonlimiting embodiment, the heat sink 13 is made of a thermally conductive material. In a nonlimiting example, it is made of a metallic material or of thermally conductive plastic. It thus dissipates heat. In a nonlimiting variant, the heat sink 13 is made of steel or aluminum. These materials are inexpensive. In addition, aluminum is a light component and is a good thermal conductor.

In a nonlimiting embodiment illustrated in Figures 3, 5, 9, 12, 15, 16 and 19, the heat sink 13 further comprises two pins

26A, 26B adapted to pre-position the heat sink 13 relative to the upper part 3A of the housing 3 under the printed circuit board 5, the final positioning being ensured by the lower part 3B of the housing 3. These pins 26A, 26B are arranged on the main part 13A (described below) of the heat sink 13, in particular on the surface of the main part 13A which comes into contact with the printed circuit board 5. They are arranged on either side of the printed circuit board 5.

In another nonlimiting embodiment (not illustrated), the heat sink 13 comprises two holes adapted to cooperate with two pins of the upper part 3A of the housing 3 so as to pre-position the heat sink 13 relative to the upper part 3A of the housing 3 under the printed circuit board 5.

The heat sink 13 is made up of several parts. It can also take various forms.

The light device 1 is described below according to three non-limiting embodiments, these embodiments comprising a heat sink 13 of varied shape.

o P irst method. of. realization

In a first embodiment illustrated in Figures 1 to 9, the heat sink 13 has a U-shaped section. This heat sink 13 thus comprises a main part 13A and two secondary parts 13B, 13C which extend from this main part 13A. In a nonlimiting embodiment, the main part 13A and the secondary parts 13B, 13C are made of the same basic material.

In a nonlimiting embodiment, the heat sink 13 is formed during a single operation, for example during an extrusion operation.

In another non-limiting embodiment, the heat sink 13 is formed during several operations, for example cutting and folding to obtain the secondary parts 13B, 13C and the main part 13A, or cutting and welding the secondary parts

13B, 13C with the main part 13A.

As illustrated in FIGS. 1 to 9, in a nonlimiting embodiment, the secondary parts 13B, 13C are substantially parallel to one another and form respectively with the main part 13A a substantially right angle. This facilitates the mounting of the heat sink 13.

In another nonlimiting embodiment, the angle formed by the secondary parts 13B, 13C with the main part 13A is different from 90 degrees. Thus, in a nonlimiting variant, the angle is less than 90 degrees. This avoids elastic return of said secondary walls 13B, 13C during a folding process to obtain said secondary walls 13B, 13C, elastic return which could cause an angle greater than 90 °. Furthermore, an undercut is obtained to pre-maintain the heat sink 13 on the housing 3. Thus, for the third alternative embodiment of Figures 8 and 9 described below, this facilitates the pre-maintenance of the heat sink 13 on the upper part 3A of the housing 3 before sandwiching the heat sink 13 with the lower part 3B of the housing 3. This prevents the heat sink 13 and the upper part 3A from disassembling due to gravity before the final assembly with the lower part 3B. Finally, this reduces the size of the heat sink 13.

In a nonlimiting embodiment, the ends of the secondary walls 13B, 13C (which are in the direction of the upper part 3A of the housing 3 during assembly) are chamfered so as to facilitate the insertion of the upper part 3A between the secondary walls 13B, 13C of the heat sink 13. Thus, this embodiment applies in particular to the third alternative embodiment of Figures 8 and 9 described below.

According to this first nonlimiting embodiment, the mounting of the heat sink 13 is done vertically relative to the plane of the printed circuit board 5 and of the housing 3.

First variant

In a first non-limiting alternative embodiment illustrated in FIGS. 1 to 3, the secondary parts 13B, 13C are directed towards the lower part 3B of the housing 3, namely in a direction opposite to the printed circuit board 5, and the lower part 3B of the housing 3 comprises a notch 15 for receiving the heat sink 13.

As illustrated in Figures 1 to 3, the heat sink 13 is housed in a notch 15 of the housing 3. In particular, it is the main part 13A of the heat sink 13 which rests on this notch 15.

The mounting of the heat sink 13 is carried out when the housing 3 is open, that is to say before having placed the lower part 3B of the housing 3 under the printed circuit board 5.

Second variant of realization

In a second non-limiting alternative embodiment illustrated in FIGS. 4 to 7, the secondary parts 13B, 13C of the heat sink 13 are directed towards the lower part 3B of the housing 3, namely in a direction opposite to the printed circuit board 5 , and the lower part 3B of the housing 3 comprises a light 25 for receiving the heat sink 13. The heat sink 13 is inserted into said light 25.

As illustrated in the sectional view of FIG. 5, the heat sink 13 is inserted into the lumen 25 of the lower part 3B of the housing 3. In particular, it is the main part 13A of the heat sink 13 which is inserted and housed in this lumen 25 of the lower part 3B of the housing 3. Thus, the heat sink 13 is well positioned and held in place. In the nonlimiting example illustrated, pins 26B and 26A are shown on the heat sink 13. Of course, in another variant, the heat sink 13 may not include such pins or may include holes cooperating with pins located in the upper part 3A as described above.

The assembly of the heat sink 13 is carried out once the housing 3 is closed, namely after having placed the lower part 3B of the housing 3 under the printed circuit board 5.

In order to maintain the heat sink 13 in the lumen 25, in a nonlimiting embodiment, the heat sink 13 comprises means for hooking on the lower part 3B of the housing 3.

In a first non-limiting alternative embodiment illustrated in FIG. 6, the hooking means comprise a notch-tongue 14 adapted to hang on one end 16 of the lower part 3B.

In particular, each secondary part 13B of the heat sink 13 comprises a notch-tab 14 for hooking onto one end 16 of the lower part 3B of the housing 3. The lower part 3B thus comprises two ends 16 arranged opposite one another one on the other and on both sides of the light 25.

In a second nonlimiting alternative embodiment illustrated in FIG. 7, the attachment means comprise a plurality of teeth 18 adapted to hang on an inner surface 20 of the lower part 3B of the housing 3. The teeth 18 belong to the parts secondary 13B, 13C of the heat sink. In particular, each secondary part 13B of the heat sink 13 comprises teeth 18 for hooking to an internal surface 20 of the lower part 3B of the housing 3. The lower part 3B thus comprises two internal surfaces 20 opposite one another. 'from each other and on either side of the lumen 25 on which the teeth 18 hang.

The teeth are in the shape of a sawtooth or a so-called “fir tree” shape.

Thus, when the heat sink 13 is inserted into the lumen 25 of the lower part 3B of the housing 3, the teeth 18 do not hinder the insertion. On the other hand, if an operator subsequently tries to remove the heat sink 13 from the housing 3, the teeth 18 catch on the inner surface 20 of the lower part 3B of the housing 3.

Third variant of.

In a third nonlimiting variant illustrated in FIGS. 8 and 9, the secondary parts 13B, 13C are directed towards the upper part of the housing 3A, namely in the direction of the printed circuit board 5, and the lower part 3B of the housing 3 includes a notch 15 for receiving the heat sink 13.

These secondary parts 13B, 13C surround the printed circuit card 5 in the housing 3. In this way, it is possible to limit the relative movements of the printed circuit card 5 relative to the housing 3 when said housing is closed.

As illustrated in Figures 8 and 9, the heat sink 13 is housed in a notch 15 of the housing 3. In particular, it is the main part 13A of the heat sink 13 which rests on this notch 15.

The mounting of the heat sink 13 is carried out when the housing 3 is open, that is to say before having placed the lower part 3B of the housing 3 under the printed circuit board 5.

The secondary walls 13B, 13C are arranged between them so that they can pre-maintain the heat sink 13 on the upper part 3A of the housing 3. Thus, as described above, they are parallel to each other or not.

As illustrated in FIGS. 8 and 9, in a nonlimiting embodiment, the light device 10 further comprises means for fixing 17, 19 of the heat sink 13 to the housing 3. These fixing means comprise at least:

- A clip 17, this clip belonging to the housing 3A;

a notch 19 for receiving the clip 17, this notch 19 belonging to the heat sink 13.

o Second embodiment

In a second embodiment illustrated in Figures 10 to 12, the heat sink 13 comprises a main part 13A and two secondary parts 13B, 13C framing the main part 13A, and the lower part 3B of the housing 3 includes a notch 15 for receiving the heat sink 13.

In this second embodiment, the heat sink 13 has an H-shaped section.

In a nonlimiting embodiment, the main part 13A and the secondary parts 13B, 13C are made of the same basic material.

In a nonlimiting embodiment, the heat sink 13 is formed during a single forming operation, for example during an extrusion operation.

In another nonlimiting embodiment, the heat sink 13 is formed during several operations, for example during several cutting and folding operations to obtain the secondary parts 13B, 13C and the main part 13A, or cutting and welding of the secondary parts 13B, 13C with the main part 13A.

The mounting of the heat sink 13 is carried out when the housing 3 is open, that is to say before having placed the lower part 3B of the housing 3 under the printed circuit board 5.

The secondary walls 13B, 13C are arranged between them so that they can pre-maintain the heat sink 13 on the upper part 3A of the housing 3.

As illustrated in FIGS. 10 to 12, in a nonlimiting embodiment, the secondary parts 13B, 13C are substantially parallel to one another and form respectively with the main part 13A a substantially right angle. This facilitates the mounting of the heat sink 13.

In another nonlimiting embodiment, the angle formed by the secondary parts 13B, 13C with the main part 13A is different from 90 degrees. Thus, in a nonlimiting variant, the angle is less than 90 degrees. This avoids elastic return of said secondary walls 13B, 13C during the folding process to obtain said secondary walls 13B, 13C, elastic return which could cause an angle greater than 90 °. Furthermore, an undercut is obtained to pre-maintain the heat sink 13 on the housing 3. Thus, this facilitates the pre-maintenance of the heat sink 13 on the upper part 3A of the housing 3 before sandwiching the heat sink 13 with the lower part 3B of the housing 3. This prevents the heat sink 13 and the upper part 3A from disassembling due to gravity before the final assembly with the lower part 3B. Finally, this reduces the size of the heat sink 13.

In a nonlimiting embodiment, the ends of the secondary walls 13B, 13C (which are in the direction of the upper part 3A of the housing 3 during assembly) are chamfered so as to facilitate the insertion of the upper part 3A between the secondary walls 13B, 13C of the heat sink 13.

As illustrated in Figures 10 or 12, each edge of the main part 13A is located in the center of each secondary part 13B, 13C.

In another nonlimiting embodiment, the secondary parts 13B, 13C can be offset in height relative to this main part 13A.

As illustrated in FIGS. 10 and 12, the heat sink 13 is housed in a notch 15 of the housing 3. In particular, it is the main part 13A of the heat sink 13 which rests on this notch 15.

As illustrated in FIGS. 10 to 12, the light device 10 comprises means for fixing 17, 19 of the heat sink 13 to the housing 3.

These fixing means include at least:

- A clip 17, this clip belonging to the housing 3A;

a notch 19 for receiving the clip 17, this notch 19 belonging to the heat sink 13.

According to this second nonlimiting embodiment, the mounting of the heat sink 13 is done vertically with respect to the plane of the printed circuit board 5 and of the housing 3.

o Third embodiment

In a third embodiment illustrated in Figures 13 to 19, the heat sink 13 comprises two nested folds 21 A, 21 B.

This third embodiment improves the evacuation of heat out of the printed circuit board 5 because it increases the heat exchange surface between an air flow and the heat sink 13.

The folding 21A includes:

- a basic part 21 C ’;

- a secondary part 21A;

- a fold 21 A ”which separates the two parts 21A and 21 C’.

The folding 21B includes:

- the basic part 21 C ’;

- a secondary part 21 B ’;

- a fold 21 B ”which separates the two parts 21 B’ and 21 C ’.

The two folds 21 A, 21B are nested because they include:

- the basic part 21 C ’common; and

- the respective abutments 21 A ’, 21 B’ which are superimposed between them.

In a nonlimiting embodiment, the two superimposed secondary parts 21 A, 21 B ’are parallel to the base part 21 C’.

The base part 21 C 'and the secondary part 21 B' which is closest to the base part 21 C '(FIG. 14 or FIG. 18) delimit a first space E1 adapted to accommodate the lower part 3B of the housing 3. The latter is in fact adapted to fit into this first space E1.

The two superimposed secondary parts 21 A ', 21 B' (Figure 14) or the base part 21'C and the most distant secondary part 21A from the base part 21 C '(Figure 18) delimit a second space E2 by which an air flow can pass. This makes it possible to considerably increase the heat exchange surface between an air flow and the heat sink 13 compared to the first and second embodiments of the heat sink 13 described above.

The dimension of the two superimposed secondary parts 21 A, 21 B 'is defined according to the need in terms of heat dissipation. Thus, their dimensions can be the same or different. In a nonlimiting embodiment, the two superimposed secondary parts 21 A ', 21 B' have the same dimension as illustrated in FIG. 14. In another nonlimiting embodiment, the two superimposed secondary parts 21 A ' , 21 B 'have different dimensions as illustrated in FIG. 18. This makes it possible to have a second larger space E2 to allow more air flow to pass.

In a first non-limiting alternative embodiment illustrated in FIG. 13, the lower part 3B of the housing 3 comprises a notch 15 for receiving the heat sink 13. The base part 21 C ′ is thus adapted to rest on the lower part 3B of the housing at the notch 15.

In this case, the mounting of the heat sink 13 is carried out when the housing 3 is open, that is to say before having placed the lower part 3B of the housing 3 under the printed circuit board 5 to close it.

The assembly is carried out horizontally relative to the plane of the printed circuit board 5 and of the housing 3. The lower part 3B of the housing 3 is inserted into the first space E1 of the heat sink 13.

In the nonlimiting example illustrated in FIG. 15, the base part 21 C ’rests entirely on the lower part 3B of the housing.

When the base part 21 C ’of the heat sink 13 rests on the notch 15 of the lower part 3B of the housing 3, the housing 3 can be closed by positioning the lower part 3B under the printed circuit board 5.

In a second non-limiting alternative embodiment illustrated in FIG. 16, the lower part 3B of the housing 3 comprises a slot 25 for accommodating the heat sink 13. The housing 3 is thus partly open.

The heat sink 13 is inserted into said lumen 25.

In this case, the mounting of the heat sink 13 is carried out when the housing 3 is closed, namely after having placed the lower part 3B of the housing under the printed circuit board 5.

The assembly is carried out vertically with respect to the plane of the printed circuit board 5 and of the housing 3. In the nonlimiting example illustrated in FIG. 16, the base part 21 C ′ is inserted and housed in the lumen 25 of the lower part 3B of the housing 3. It is thus possible to partially house the heat sink 13 in the lumen 25 once the housing 3 is closed.

The same attachment means as those illustrated in FIGS. 6 and 7 for the first embodiment of the heat sink 13 can be used.

The nested folds are described below according to two nonlimiting alternative embodiments.

In a first nonlimiting alternative embodiment illustrated in FIG. 14, the folds 21 A, 21B are full, namely their respective abutments 21 A ’, 21 B’ are full.

In a second nonlimiting alternative embodiment illustrated in FIG. 18, at least one of the folds 21 A, 21B comprises a plurality of fins 27 separated by openings 23. Thus, the fold 21A comprises fins 27 on its secondary part 21 A 'and / or folding 21B comprises fins 27 on its secondary part 21 B'. The presence of fins 27 increases the heat exchange surfaces and promotes the extraction of heat from the printed circuit board 5.

Of course, the description of the invention is not limited to the embodiments described above.

Thus, in another nonlimiting embodiment, the light device 10 is suitable for a lighting device for a motor vehicle, said lighting device being adapted to provide a determined photometric function. In a nonlimiting embodiment, such a lighting device is a headlight for a motor vehicle. In nonlimiting embodiments, the photometric function is:

- a photometric function called "high beam" to achieve a high beam; or

- a photometric function called "low beam" to achieve, for example, a low beam.

Thus, in another nonlimiting embodiment, the reception area 3A of the housing 3 can include a non-cylindrical section for receiving a non-cylindrical light guide.

Thus, in another nonlimiting embodiment, the secondary parts 5 13B, 13C can form an angle with the main part 13A greater than

90 ° if they can pre-maintain the heat sink 13 on the upper part 3A of the housing 3.

Thus, the invention described has the following advantages in particular:

- the accumulation of heat in the housing is avoided. This prevents degradation of the light source or of the control module, thus preventing a partial or total loss of their lighting or control function;

- heat dissipation outside the housing is improved;

the optical performance of the light source is maintained over time;

- the light device is compact and can be easily and discreetly inserted into the interior of a motor vehicle.

Claims (17)

1. Lighting device (10) for a motor vehicle comprising: - a housing (3); - a printed circuit board (5) housed in the housing (3) and comprising a first face (5A) and a second face (5B); - a light source (7) disposed on said first face (5A) of the printed circuit board (5); - a control module (9) of the light source (7); - a heat sink (13), said heat sink (13) being in contact with said second face (5B) of the printed circuit board (5) opposite to said first face (5A) of said printed circuit board (5) carrying said light source (7). 2. A light device (10) according to claim 1, wherein a part of the heat sink (13) extends outside the housing (3). 3. Light device (10) according to claim 1 or claim 2, wherein the heat sink (13) is metallic or thermally conductive plastic. 4. Illuminating device (10) according to any one of the preceding claims 1 to 3, in which the heat sink (13) comprises a main part (13A) and two secondary parts (13B, 13C) extending from the main part (13A) so that said heat sink (13) has a U-shaped section. 5. Light device (10) according to claim 4, wherein the secondary parts (13B, 13C) are directed towards a lower part (3B) of the housing (3). 6. Lighting device (10) according to claim 4, wherein the secondary parts (13B, 13C) are directed towards an upper part (3A) of the housing (3) so as to frame the printed circuit board (5). 7. Light device (10) according to any one of the preceding claims 1 to 6, in which the housing (3) has a lower part (3B) comprising a notch (15) adapted to accommodate said heat sink (13). 8. Luminous device (10) according to any one of the preceding claims 1 to 6, in which the housing (3) comprises a lower part (3B) comprising a light (25) adapted to receive said heat sink (13). 9. Light device (10) according to any one of the preceding claims 1 to 3, in which the heat sink (13) comprises a main part (13A) and two secondary parts (13B, 13C) framing the main part (13A). so that said heat sink (13) has an H-shaped section. 10. Light device (10) according to any one of the preceding claims 1 to 9, in which said light device (10) comprises means for fixing (17, 19) of the heat sink (13) on said housing (3), said fixing means (17, 19) comprising, at least: - a clip (17), said clip (17) belonging to said housing (3); - a notch (19) adapted to receive said clip (17), said notch (19) belonging to said heat sink (13). 11. Luminous device (10) according to any one of claims 1 to 3, in which the heat sink (13) comprises two nested folds (21 A, 21 B). 12. Light device (10) according to claim 11, in which the two overlapping folds (21 A, 21 B) comprise: - a common base part (21 C ’); and - respective secondary parts (21 A ’, 21 B’) which are superimposed between them. 13. A light device (10) according to claim 11 or claim 12, wherein at least one of the folds (21 A, 21 B) comprises a plurality of fins (27). 14. Lighting device according to any one of the preceding claims 1 to 13, in which the housing (3) is opaque. 15. Light device (10) according to any one of the preceding claims 1 to 14, in which the light source (7) is a semiconductor emitting chip. 16. A light device (10) according to claim 15, in which the semiconductor emitting chip is part of an incandescent light-emitting diode. 17. Light device (10) according to any one of the preceding claims 1 to 16, in which the light source (7) is an RGB light source.