Lighting control module for a motor vehicle

Abstract

The invention discloses a control module (10) for a vehicle, said module comprising:-a front face (12) comprising an outer layer (14) comprising a pictogram (16),-a control unit,-a flexible printed circuit board (18) on an inner plate (20) of the front face (12), comprising a capacitive antenna (22) for detecting the approach of an object. The pictogram (16) faces the antenna (22). The printed circuit board (18) comprises light emitting diodes (24) for backlighting the pictogram (16). The diode (24) is top-emitting and is placed on an end portion (30) of the printed circuit board (18), which end portion is fixed to a portion (32) of the front face (12), which portion (32) is perpendicular to a portion (34) of the front face comprising the pictogram (16). The module (10) comprises a reflector (36) facing the pictogram (16) such that a majority of the light beam emitted by the diode (24) is reflected by the reflector (36) towards the pictogram (16).

Description

Technical Field

[0001] The present invention relates to a lighting control module for a motor vehicle. Background Art

[0002] In the passenger compartment of a vehicle, control modules are used that allow a user to control the on-vehicle systems of the vehicle.

[0003] Some control modules are also provided with capacitive sensors equipped with capacitive antennas for detecting the approach of a user's finger to an interface. Such proximity detection can allow the interface to be activated before the user touches the interface.

[0004] The control module enables the user, driver or passenger to control the on-vehicle systems of the vehicle, such as the air conditioning system, radio system, music system, telephone system, ventilation system or navigation system.

[0005] Generally speaking, the control module includes a front face having pictograms located near the control elements. The prior art has disclosed such a control module that includes a flexible printed circuit board carrying a capacitive antenna for detecting the approach of a user's finger. In such a prior art module, the printed circuit board fixed to the inner plate of the front face of the module incorporates light-emitting diodes for illuminating the pictograms from behind. For example, backlighting can thus be controlled by capacitive detection so that it is easier to select the pictograms and the associated control elements, for example when driving at night. In such a prior art module, edge-emitting light-emitting diodes are used, that is to say, the light-emitting diodes have a face that emits laterally with respect to the diode carrier.

[0006] For example, such edge-emitting diodes (also known as EELDs) are known from document EP3161912A1 or document FR3022869. Such diodes are formed from a stack of semiconductors with different doping levels and are designed such that the light is emitted laterally with respect to the layer stack and is thus called "edge emission".

[0007] However, in this prior art module, the illumination of the pictograms and other surfaces to be illuminated is not uniform enough. In addition, the structure of edge-emitting diodes is more complex, so the manufacturing cost is higher. Moreover, the use of edge-emitting diodes requires the use of light guides, which also increases the cost price. In addition, due to the proximity between the diodes and the capacitive antenna, the diodes interfere with the operation of the capacitive sensor, resulting in module failure. The presence of the diodes below the front face causes a dent effect visible on the surface of the module, which is the reason for the non-uniform appearance of the module and may lead to its rejection. The use of edge-emitting diodes is also associated with a significant horizontal coverage area because the edge-emitting diodes must be spaced sufficiently apart to obtain uniform illumination over the entire surface. Finally, in order to control the emission uniformity, it is necessary to use multiple diodes for a single pictogram. Summary of the Invention

[0008] The present invention particularly aims to propose an improved lighting control module for a motor vehicle, which at least partially overcomes the above-mentioned drawbacks.

[0009] To this end, the subject of the present invention is a lighting control module for a motor vehicle, the module comprising:

[0010] A front face, including an outer layer, the outer layer including at least one pictogram,

[0011] At least one control member,

[0012] A flexible printed circuit board, fixed to the inner board of the front face and including at least one capacitive antenna, the at least one capacitive antenna being used to detect the approach of an object towards the control member,

[0013] Wherein the pictogram is positioned facing the capacitive antenna,

[0014] The flexible printed circuit board incorporates at least one light-emitting diode for illuminating the pictogram from behind,

[0015] Wherein:

[0016] The light-emitting diode is a top-emitting LED,

[0017] The light-emitting diode is arranged on an end portion of the flexible printed circuit board, the end portion being for fixing to a part of the front face that is perpendicular to the part of the front face including the pictogram,

[0018] The control module further includes a light reflector arranged opposite the pictogram such that most of the light beam emitted by the diode is reflected by the light reflector towards the pictogram.

[0019] Thus, the diode is not located below the pictogram. This makes it possible to apply a minimum distance between the diode and the capacitive antenna, thereby limiting the interference effect of the diode on the antenna. This also prevents the indentation from being seen from outside the module.

[0020] A top-emitting diode (also known as a top-emitting LED) is a "standard" diode. These are the cheapest standard light-emitting diodes. These standard LEDs are also manufactured from a stack of semiconductor layers, but the light cone is emitted from the top of the stack, hence the name top-emitting LED. In terms of its cone, it is different from an edge-emitting diode because the light-emitting surface of the diode is the surface located at the top of the stack of semiconductor layers. Such a top-emitting diode is known, for example, from document FR3064531.

[0021] "Most of the light beam" corresponds to at least half of the light beam.

[0022] According to one aspect, the part of the front face that is perpendicular to the part including the pictogram is, for example, an area for fixing the front face to the support housing.

[0023] The part of the front face that is perpendicular to the part including the pictogram can be made of an opaque material, such as black polycarbonate.

[0024] According to another aspect, the flexible printed circuit board is transparent to light.

[0025] The flexible printed circuit board can be fixed to the inner plate of the front face by overmolding, bonding or any other assembly method.

[0026] According to further optional features adopted individually or in combination for the lighting control module:

[0027] For example, the flexible printed circuit board is fixed to the inner plate of the front face by overmolding.

[0028] Thus, the bonding step is avoided. In addition, the adhesive reduces the detection sensitivity of the capacitive antenna and becomes an obstacle to the diffusion of light towards the pictogram.

[0029] The overmolding is especially made of a material that is transparent to light, such as white polycarbonate.

[0030] The flexible printed circuit board is especially fixed to the inner plate of the front face by overmolding.

[0031] The light-emitting diode is, for example, partially overmolded in the inner plate so that its emission surface is flush, that is to say not covered by the material of the inner plate.

[0032] The outer layer can be made of an opaque material, such as black polycarbonate, and the pictogram can be made of a light-transmitting or translucent material, such as white polycarbonate.

[0033] The front face includes, for example, a light diffusing plate disposed between the outer layer and the flexible printed circuit board.

[0034] It should be understood that the light diffusing plate is made of a material that is particularly transparent or translucent to light, such as white polycarbonate.

[0035] The diffusing plate enables the light reflected towards the pictogram to be homogenized.

[0036] The pictogram is particularly located on the outer face of the outer layer, and the diffusing cylinder extends from the diffusing plate to the pictogram in the outer layer.

[0037] The diffusing cylinder can be integrally formed with the diffusing plate, especially by integral molding. Optionally, the diffusing cylinder and the diffusing plate form a single piece.

[0038] The outer layer is particularly manufactured by double injection of a material that is transparent or translucent to light to produce the pictogram and a material that is opaque to light to produce the non-pictogram part of the outer layer.

[0039] The diffusing plate and the diffusing cylinder are made by double injection of a material that is transparent or translucent to light, for example.

[0040] The outer layer is a decorative plastic film.

[0041] This film is made of polycarbonate, for example.

[0042] Optionally, the pictogram is printed on the decorative plastic film.

[0043] Optionally, the pictogram is obtained by scratching the decorative plastic film.

[0044] The pictogram can be obtained by laser engraving.

[0045] The decorative plastic film can be overmolded on the inner plate.

[0046] The outer layer can also be a paint coating, especially an opaque paint, such as a black paint. Using the same method as that mentioned for the decorative plastic film, the pictogram can be obtained on the paint coating.

[0047] The light reflector is offset from the light-emitting diode arrangement.

[0048] This means that the reflector is not positioned opposite the diode, and the light rays emitted by the diode that reach the reflector are light rays that form a non-zero angle with the longitudinal axis of the light beam emitted by the diode.

[0049] The reflector is, for example, a white plastic part or a mirror.

[0050] The light reflector includes at least one part positioned opposite the light-emitting diode, and a part of the light beam emitted by the light-emitting diode diffuses into the light reflector, so as to be reflected from the surface of the light reflector and then diffuse towards the pictogram in the reflector.

[0051] Diffusion in the reflector enables the pictogram to be illuminated more evenly. BRIEF DESCRIPTION OF THE DRAWINGS

[0052] The present invention can be better understood by reading the following description given only by way of example and by referring to the drawings, in which:

[0053] Figure 1 is a schematic view of a lighting control module according to a first embodiment of the present invention;

[0054] Figure 2 is a schematic view of a lighting control module according to a second embodiment of the present invention;

[0055] Figure 3 is a schematic view of a lighting control module according to a third embodiment of the present invention. DETAILED DESCRIPTION OF THE INVENTION

[0056] Figure 1 There is shown a lighting control module for a motor vehicle according to a first embodiment of the present invention, designated by the general reference numeral 10. The control module 10 includes a front face 12 and at least one control member, not shown. The front face 12 provides access for a user to the control member. The front face 12 is rigid, for example made of plastic. It has in particular a decorative function. The control member allows a user, driver or passenger who activates it to control at least one on-board system of the vehicle, such as an air-conditioning system, a radio system, a music system, a telephone system, a ventilation system or a navigation system. The front face 12 includes an outer layer 14, the outer layer 14 including at least one symbol or pictogram 16, two pictograms in the example shown. The pictogram 16 corresponds to at least one respective control element.

[0057] The control module 10 further includes a flexible printed circuit board 18, fixed to an inner panel 20 of the front face 12. The flexible printed circuit board 18 includes at least one capacitive antenna 22, two capacitive antennas in the example shown. The capacitive antenna 22 makes it possible to detect the approach of an object (not shown) to the control member, starting from a distance of approximately 40 millimeters, the object being for example one or more fingers of a user or the palm of a user. This detection can allow the control module to be activated before the user touches it. The pictogram 16 is positioned facing the capacitive antenna 22.

[0058] ​​​The printed circuit board 18 includes at least one light-emitting diode 24 for backlighting the pictogram 16. The light-emitting diode 24 is a top-emitting LED. These top-emitting diodes include a stack of semiconductor layers and emit a light cone from the top of the stack, thus being called top-emitting LEDs. In terms of its cone, it is different from edge-emitting diodes because the light-emitting surface of the diode is the surface located at the top of the stack of semiconductor layers. Such top-emitting diodes are known, for example, from the document FR3064531.

[0059] In the present embodiment, the emission surface 26 of the diode 24 is positioned parallel to the carrier 28 of the diode 24.

[0060] The light-emitting diode 24 is mounted on the end portion 30 of the flexible printed circuit board 18. The end portion 30 is intended to be fixed to the portion 32 of the front face 12, which portion 32 is perpendicular to the portion 34 of the front face 12 that includes the pictogram 16. In Figure 1 the example, the parts 32 and 34 form the same part. The portion 32 of the front face that is perpendicular to the portion 34 including the pictogram, called the "vertical portion", is, for example, the area for fixing the front face 12 to a support housing (not shown). In the example shown, the vertical portion 34 is made of an opaque material, such as black polycarbonate. In this example, the printed circuit board 18 is transparent to light.

[0061] The module 10 also includes a light reflector 36 disposed opposite the pictogram 16 such that most of the light beam emitted by the diode 24 is reflected by the light reflector 36 towards the pictogram 16. This part of the light beam reflected by the light reflector 36 towards the pictogram 16 is represented by three arrows.

[0062] In Figure 1 the example, the printed circuit board 18 is fixed to the inner plate 20 of the front face 12 by overmolding. More precisely, the printed circuit board 18 is fixed in the inner plate 20 of the front face 12 by overmolding. The diode 24 is partially overmolded in the inner plate 20 such that its emission surface 26 is flush, that is, not covered by the material of the inner plate 20.

[0063] Furthermore, the outer layer 14 is made of an opaque material, such as black polycarbonate, and the pictogram 16 is made of a light-transmitting or translucent material, such as white polycarbonate.

[0064] Furthermore, the front face 12 includes a light diffusing plate disposed between the outer layer 14 and the printed circuit board 18. In Figure 1 the example, the diffusing plate is the inner plate 20. The light diffusing plate 20 is made of a material that is transparent or translucent to light, such as white polycarbonate. This makes it possible to homogenize the light reflected towards the pictogram 16.

[0065] Also in Figure 1In the example, the pictogram 16 is located on the outer face 38 of the outer layer 14, and the diffuser tube 40 extends from the diffuser plate 20 to the pictogram 16 in the outer layer 14. The diffuser tube 40 is integrally formed with the diffuser plate 20. It is integrally molded with the diffuser plate 20. It forms a single piece with the diffuser plate 20.

[0066] The outer layer 14 is manufactured by double injection of a light-transparent or translucent material to produce the pictogram 16 and a light-opaque material to produce the parts of the outer layer that are not the pictogram 16. Manufacturing the outer layer 14 by double injection also makes it possible to manufacture the diffuser plate 20 and the diffuser tube 40.

[0067] The light reflector 36 is offset from the light-emitting diode 24. The reflector 36 is thus not positioned opposite the diode 24, and the light rays emitted by the diode 24 that reach the reflector 36 are light rays that form a non-zero angle with the longitudinal axis of the light beam emitted by the diode 24. The reflector 36 is, for example, a white plastic part or a mirror.

[0068] Figure 2 A motor vehicle lighting control module 10 according to a second embodiment of the invention is shown.

[0069] In this Figure 2 and Figure 3 element similar to the Figure 1 element in

[0070] In this example and Figure 3 the example of

[0071] Furthermore, in Figure 3 the example of

[0072] The invention is not limited to the described embodiments, and other embodiments will be apparent to those skilled in the art.

[0073] List of reference numerals

[0074] 10: Control module

[0075] 12: Front face

[0076] 14: Outer layer of the front face

[0077] 16: Pictogram

[0078] 18: Flexible printed circuit board

[0079] 20: Inner plate of the front surface

[0080] 22: Capacitive antenna

[0081] 24: Light-emitting diode

[0082] 26: Emission surface of the diode

[0083] 28: Diode carrier

[0084] 30: End portion of the printed circuit board

[0085] 32: Vertical portion

[0086] 34: Portion including pictogram

[0087] 36: Light reflector

[0088] 38: Outer surface of the outer layer

[0089] 40: Diffusion barrel

[0090] 42: Portion of the reflector disposed opposite to the diode

Claims

1. A lighting control module (10) for a motor vehicle, the module (10) comprising: including a front face (12) of an outer layer (14), the outer layer including at least one pictogram (16), at least one control member, a flexible printed circuit board (18), fixed to an inner plate (20) of the front face (12) and including at least one capacitive antenna (22) for detecting the approach of an object towards the control member, wherein the pictogram (16) is positioned facing the capacitive antenna (22), the flexible printed circuit board (18) including at least one light-emitting diode (24) for illuminating the pictogram (16) from behind, wherein: the light-emitting diode (24) is a top-emitting LED, the light-emitting diode (24) is arranged on an end portion (30) of the flexible printed circuit board (18) for fixing to a part (32) of the front face (12) that is perpendicular to a part (34) of the front face including the pictogram (16), the control module (10) further includes a light reflector (36) arranged opposite the pictogram (16) such that most of the light beam emitted by the light-emitting diode (24) is reflected by the light reflector (36) towards the pictogram (16).

2. The lighting control module (10) according to the preceding claim, wherein, The flexible printed circuit board (18) is fixed to the inner plate (20) of the front face (12) by overmolding.

3. The lighting control module (10) according to any one of the preceding claims, wherein, The outer layer (14) is made of an opaque material, such as black polycarbonate, and the pictogram (16) is made of a light-transmissive or translucent material, such as white polycarbonate.

4. The lighting control module (10) according to any one of the preceding claims, wherein, The front face (12) includes a light diffusing plate (20) disposed between the outer layer (14) and the flexible printed circuit board (18).

5. The lighting control module (10) according to the preceding claim, wherein, The pictogram (16) is located on an outer surface (38) of the outer layer (14), and a diffusion cylinder (40) extends in the outer layer (14) from the diffusion plate (20) to the pictogram (16).

6. The lighting control module (10) according to the preceding claim, wherein, The diffusion cylinder (40) is integrally formed with the diffusion plate (20), such as integrally molded.

7. The lighting control module (10) according to any one of the preceding claims, wherein, The outer layer (14) is made by double injection of a transparent or translucent material to produce the pictogram (16) and an opaque material to produce the non-pictogram parts of the outer layer (14).

8. The lighting control module (10) according to claim 7 in combination with claim 5 or 6, wherein, The diffusion plate (20) and the diffusion cylinder (40) are manufactured by double injection of a material that is transparent or translucent to light.

9. The lighting control module (10) according to any one of claims 1 to 4, wherein, The outer layer (14) is a decorative plastic film.

10. The lighting control module (10) according to any one of the preceding claims, wherein, The light reflector (36) is arranged offset from the light-emitting diode (24).

11. The lighting control module (10) according to any one of claims 1 to 9, wherein, The light reflector (36) includes at least one part (42) positioned opposite the light-emitting diode (24), and a part of the light beam emitted by the light-emitting diode (24) diffuses into the light reflector (36) to be reflected from the surface of the light reflector and then diffuses in the light reflector (36) towards the pictogram (16).

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