FR3110215A1 - Light module for lighting and / or signaling a motor vehicle including a twisted light guide - Google Patents

Abstract

The invention relates to a light module for the lighting and/or signaling of a motor vehicle comprising a twisted light guide. The light module (2A) comprises a light guide (4) extending between a proximal end (8 ) and a distal end (10). A first light source (6) is arranged opposite the proximal end (8) of the light guide (4), so as to allow the propagation of a light beam between large faces (16) of the light guide and along a direction of propagation (18) parallel to the major faces (16). The light guide (4) comprises diffusing elements to deflect the light propagating in the light guide (4) towards the large faces (16). The invention is remarkable in that along the direction of propagation (18), the large faces (16) of the light guide (4) are twisted. (Figure 1)

Description

Light module for the lighting and/or signaling of a motor vehicle comprising a twisted light guide

Technical field to which the invention relates

The present invention relates to the technical field of light modules for the lighting and/or signaling of motor vehicles. The present invention relates more particularly to a light module intended to be mounted in an optical unit for a motor vehicle.

Technology background

For safety reasons, the regulations require that each motor vehicle be equipped with light modules for lighting and signaling, so as to allow road users to easily identify the position as well as the intentions of motor vehicles.

In a known way, a light module consists of a light source illuminating an optic adapted to project a light beam in accordance with the regulations in force.

Depending on the function of the light module, the regulations require that the light beam emitted respects the following specific characteristics: an appropriate color, an appropriate light intensity and a sufficient opening angle.

The value of the opening angle imposed by the regulations is of the order of 120°. In order to respect this value, it is known to use optical lenses and/or optical reflectors to increase the aperture angle of the light beam emitted by the light source.

The use of optical lenses and/or optical reflectors has the disadvantage of significantly increasing the size of the light module. As a result, the optical units integrating several light modules are of imposing dimensions, which limits the possibilities of arranging the optical units on the bodies of motor vehicles. However, the arrangement of an optical unit on a vehicle is today an important criterion of differentiation between motor vehicles.

According to another drawback, the various parts making up the light modules significantly increase the weight of the optical unit. However, reducing the weight of motor vehicles is a constant objective for manufacturers, in order to offer motor vehicles with lower energy consumption.

The present invention aims to solve the technical problems mentioned above, by proposing a luminous module for the lighting and/or signaling of a motor vehicle, which is lighter and less cumbersome compared to the state of the art, while while complying with regulatory obligations.

Object of the invention

For this, the invention proposes a light module for the lighting and/or signaling of a motor vehicle, comprising a light guide extending between a proximal end and a distal end, the light guide being delimited by two large faces parallel or substantially parallel to each other, a first light source being arranged facing the proximal end of the light guide, so as to allow the propagation of a light beam between the large faces and along a direction of propagation parallel or substantially parallel to the large faces, the light guide comprising diffusing elements capable of deflecting the light propagating in the light guide in the direction of the large faces.

The invention is remarkable in that along the direction of propagation of the light beam emitted by the first light source, the large faces of the light guide are twisted.

In other words, the large faces of the light guide perform a gyratory movement on itself, along the direction of propagation of the light beam emitted by the first light source. In other words, along the direction of propagation of the light beam, the light guide has a shape similar to a helix.

Advantageously, the original shape of the light guide makes it possible to modify, along the direction of propagation of the light beam, the orientation of a vector normal to a large face of the light guide. This feature makes it possible to significantly increase the opening angle of a light beam emitted through a large face of the light guide.

The presence of the diffusing elements in the light guide also makes it possible to increase the value of the opening angle of a beam emitted through a large face of the light guide, so as to comply with regulatory obligations without resorting to the use of an optical lens or an optical reflector.

Thus, the invention proposes a light module that is simpler in design, therefore less bulky and lighter compared to the light modules proposed by the state of the art, for the lighting and/or signaling of a motor vehicle.

According to another embodiment of the invention, in a plane normal to the direction of propagation in the light guide, of the light beam emitted by the first light source, the proximal end of the light guide extends along of a first direction of elongation and the distal end of the light guide extends along a second direction of elongation, and the first direction of elongation forms with the second direction of elongation a twist angle , the value of which is between 10° and 60°, preferably between 40° and 50°. Preferably, along the direction of propagation of the light beam in the light guide, the twist of the large faces is regular.

According to another embodiment of the invention, the distance separating the proximal end from the distal end of the light guide is between 60 mm and 120 mm, preferably between 70 mm and 80 mm.

According to another embodiment of the invention, the smallest distance separating the two large faces of the light guide is between 2 mm and 5 mm, preferably between 3 mm and 4 mm.

According to another embodiment of the invention, the light module comprises a second light source, arranged opposite the distal end of the light guide, so as to allow the propagation of a light beam in the light guide, along the direction of propagation.

According to another embodiment of the invention, at least one light source is capable of emitting a light beam of white, red and/or amber color.

According to another embodiment of the invention, at least one light source comprises several light-emitting diodes arranged along one end of the light guide. According to a preferred embodiment, at least two light-emitting diodes are capable of emitting light beams of different colors.

According to another embodiment of the invention, the light module comprises an optical reflector positioned opposite a large rear face of the light guide. Preferably, the optical reflector is parallel or substantially parallel to the large rear face of the light guide. The reflector can be light in color and/or its surface grained.

Of course, the different characteristics, variants and embodiments mentioned above can be associated with each other in various combinations, insofar as they are not incompatible or exclusive of each other.

The invention also relates to an optical unit for a motor vehicle, comprising at least one light module as described above.

Preferably, the light module is arranged in the optical unit so that the direction of propagation of the light beam emitted by the first light source is perpendicular or substantially perpendicular to the road when the optical unit is mounted on a motor vehicle, and a large front face of at least one light module is visible from outside the optical block.

The optical unit can be mounted at the front or at the rear of a motor vehicle to illuminate and/or signal the presence of the motor vehicle to other road users.

According to another embodiment of the invention, the optical unit comprises at least two light modules able to alternately emit light through their large front faces.

Preferably, the optical block comprises at least two light modules whose light sources are integral with the same plate.

According to another embodiment of the invention, the optical unit comprises at least three light modules, arranged so that their large front faces are clearly visible from outside the optical housing.

According to another embodiment of the invention, the light module or modules present in the optical unit illuminate a surface visible from the outside of the optical unit, equal to or greater than 50 cm ² . Preferably, the optical unit comprises several light modules, arranged so as to form a large continuous or discontinuous front face, the total area of which is equal to or greater than 50 cm ² .

Description of figures

The invention will be better understood, thanks to the description below, which relates to preferred embodiments, given by way of non-limiting examples, and explained with reference to the appended diagrammatic drawings, in which:

illustrates a schematic and perspective view of a first embodiment of a light module according to the invention;

illustrates a schematic and perspective view of a second embodiment of a light module according to the invention;

illustrates a schematic and perspective view of a third embodiment of a light module according to the invention;

illustrates a schematic and perspective view of a fourth embodiment of a light module according to the invention;

illustrates a schematic view of one side of an optical block according to the invention;

illustrates a schematic view of a cross section of the optical block represented by Figure 5, at different heights along the direction of propagation of a light beam in the light guides.

Detailed description of the invention

As a reminder, the invention proposes a light module for the lighting and/or signaling of a motor vehicle, lighter and less cumbersome compared to the state of the art, while respecting the regulatory obligations.

Figure 1 illustrates a first non-limiting embodiment of a light module 2A according to the invention. The light module 2A consists of a light guide 4 illuminated by a first light source 6.

The light guide 4 extends between a proximal end 8 and a distal end 10. The proximal end 8 of the light guide is delimited by a proximal face 12. The proximal face 12 is parallel or substantially parallel to a distal face 14, delimiting the distal end 10 of the light guide. The distal and proximal faces are separated by a distance of between 60 mm and 120 mm, preferably between 70 mm and 80 mm.

The proximal and distal faces are connected by two large faces 16 opposite, parallel or substantially parallel to each other. The large faces 16 are perpendicular or substantially perpendicular to the proximal face 12. The large faces 16 are separated by a distance of between 2 mm and 5 mm, preferably between 3 mm and 4 mm. The width of the large faces 16, defined in a direction parallel or substantially parallel to the proximal face 12, is between 30 mm and 60 mm, preferably between 40 mm and 45 mm.

The light guide 4 is made from a material that is transparent or translucent in daylight, preferably from one of the following materials: polycarbonate (PC) or polymethyl methacrylate (PMMA).

The first light source 6 is arranged so as to illuminate the proximal face 12 of the light guide, in order to allow the propagation of a light beam between the large faces 16, along a direction of propagation 18 parallel or substantially parallel to the large faces 16.

According to the present example, the first light source 6 comprises three separate light-emitting diodes 20, arranged along the proximal face 12 of the light guide. The light beams emitted by the light-emitting diodes 20 propagate in the light guide 4 parallel or substantially parallel to the direction of propagation 18.

The light-emitting diodes 20 are capable of emitting light beams of identical colors or else of different colors, in particular light beams of white, amber or even red color, so that the light module 2A can respectively be used as a reversing light, indicator or position light and/or braking.

The light-emitting diodes 20 are electrically powered by a control unit, not shown in FIG. 1, capable of operating each light-emitting diode 20 autonomously. The control unit is in particular programmed to operate the light-emitting diodes simultaneously, so as to illuminate the whole of the light guide 4, or alternatively in order to create dynamic visual effects.

The light guide 4 includes diffusing elements, not visible in figure 1, making it possible to deflect at least part of a light beam propagating in the light guide 4, in the direction of the large faces 16.

By way of non-limiting example, the diffusing elements are located at the level of a large rear face 22 of the light guide. The diffusing elements are configured so that part of the light beam emitted by the first light source 6 passes through a large front face 24 of the light guide 4. The aperture angle of the light beam emitted through the large face front 24 of the light guide, is between 15° and 40°, preferably of the order of 30°.

According to the present example, the diffusing elements consist of conical cavities, open on the large rear face 22 of the light guide. The tops of the cavities are oriented in the direction of the large front face 24. The internal volume of each cavity is between 48,000 μm ³ and 536,000 μm ³ , preferably of the order of 95,000 μm ³ and 268,000 μm ³ , preferably of the order of 218,000 μm ³ . The cavities are separated, at the level of the large rear face 22 of the light guide, by a distance of between 0.12 mm and 0.7 mm, preferably between 0.13 mm and 0.5 mm. Preferably, the cavities are distributed along the direction of propagation 18, so as to promote homogeneous or substantially homogeneous diffusion of the light beam through the large front face 24 of the light guide.

As mentioned above, the regulations impose the use of light modules for the lighting and signaling of motor vehicles. The opening angle of the light beams, emitted by the light modules, must be of the order of 120° to allow good visibility of the light signal by other road users. To achieve this aperture angle value, the state of the art proposes the use of optical lenses and/or optical reflectors, to increase the aperture angle of the light beams emitted by the light sources and thus satisfy regulations. The use of these optical devices significantly increases the weight as well as the size of the light module.

The invention aims to remedy these drawbacks, by proposing an original shape of the light guide 4, along the direction of propagation 18 of a light beam, emitted by the first light source 6, in the light guide.

As illustrated by FIG. 1, the large faces 16 of the light guide are twisted along the direction of propagation 18. In other words, the large faces 16 execute a gyratory movement on themselves, along the direction spread 18.

This gyratory movement advantageously makes it possible to modify the orientation of the large front face 24 of the light guide. In FIG. 1, the orientation of the large front face 24 is represented by a normal vector 26 to said large face. It is thus observed in FIG. 1 that the orientation of the normal vector 26 changes along the direction of propagation 18.

Therefore, the orientation of the light beam emitted through the large front face 24 of the light guide, pivots along the direction of propagation 18, so that the light beam emitted through the large front face 24, illuminates a larger landscape in a plane normal to direction of propagation 18.

In other words, the light guide 4 is capable of pivoting the light beam emitted by the light module 2A, along the direction of propagation 18, so as to increase the angle of diffusion of the light which is emitted through the entire surface of the large front face 24 of the light guide.

The orientation of the light beam emitted by the first light source 6 is thus modified, without resorting to the use of a cumbersome and fragile mechanical system.

Preferably, the gyratory movement of the large faces 16 is regular along the direction of propagation 18, so that the light guide 4 is a shape similar to a helix.

In a plane normal to the direction of propagation 18, the proximal face 12 of the light guide extends along a first direction of elongation 28, and the distal face 14 of the light guide extends along a second direction of elongation 30. Preferably, the first direction of elongation 28 forms with the second direction of elongation 30, a twist angle whose value is between 10° and 60°, preferably between 40° and 50°.

The diffusing elements and the twist angle of the large faces 16 thus allow the light module 2A to emit a light signal through the large front face 24 of the light guide 4, illuminating between 80° and 130°, preferably between 110° and 130°, of a landscape included in a plane normal to the direction of propagation 18. Thus, the invention proposes a light module 2A that is simpler in design, less bulky and lighter with respect to the state of the technical, to illuminate and/or signal a motor vehicle in accordance with the regulations in force.

A second variant embodiment of a light module 2B according to the invention is illustrated by FIG. 2. The identical or similar elements between the various variant embodiments of the invention are designated by the same references in the appended figures.

The light module 2B differs from the light module 2A described above, in that it comprises a second light source 32 illuminating the distal face 14 of the light guide 4. According to the present example, the second light source 32 is identical or similar to the first light source 6, it consists of three light-emitting diodes 20 positioned along the distal face 14 of the light guide 4. This embodiment advantageously makes it possible to illuminate the large front face 24 of the guide more homogeneously. from light. According to a preferred variant embodiment, the first light source 6 and the second light source 32 emit light beams of different colors. By way of non-limiting example, the first light source can emit a light beam of red or amber color, and the second light source can emit a light beam of white color.

Figure 3 shows a third variant of a 2C light module according to the invention. The light module 2C differs from the light module 2B described above, in that it comprises an optical reflector 34, arranged opposite the large rear face 22 of the light guide 4. The optical reflector 34 is parallel or substantially parallel to the large rear face 22 of the light guide. The optical reflector 34 is preferably light in color and its surface is grained. The optical reflector 34 is positioned at a distance from the large rear face 22, so as not to modify the diffusion properties of the diffusing elements. According to the present example, the smallest distance between the optical reflector 34 and the large rear face 22 of the light guide 4 is between 0.5 mm and 1 mm.

Figure 4 shows a fourth variant of a 2D light module according to the invention. The 2D light module differs from the 2C light module described above, in that it comprises three 4 light guides arranged side by side. The proximal ends 8 of the light guides are parallel or substantially parallel to each other. The first light sources 6 are mounted on the same first plate 36. The second light sources 32 are mounted on the same second plate 38. The second plate 38 is parallel or substantially parallel to the first plate 36. Preferably, the plates serve as support for holding and electrically connecting a set of electronic components together, with the aim of producing a complex electronic circuit. By way of non-limiting example, a plate can serve as a support for the control unit of the light sources which illuminate the light guides.

The large front faces 24 of the light guides are arranged side by side, so that when the three light guides 4 are illuminated simultaneously, the 2D light module illuminates a continuous or substantially continuous surface for an observer of the light module, whose surface total at the level of the large front faces, is greater than 40 cm ² , preferably equal to or greater than 50 cm ² .

According to a variant embodiment, the first and the second light sources are controlled by a control unit not represented in FIG. 4, making it possible to illuminate each light guide with a different color simultaneously or alternatively in order to create a light animation .

Preferably, the first light sources are configured to emit a red or amber color, and the second light sources are configured to emit a white color.

According to a variant embodiment not shown, the light module can comprise at least two light guides whose angles of torsion have different values.

According to a variant embodiment not shown, the light module can comprise at least two light guides of different lengths.

According to a variant embodiment not shown, the light module may comprise at least two light guides whose large front faces are oriented differently.

Figure 5 shows a side view of an optical unit 40 for a motor vehicle. According to the present example, the optical unit is intended to be mounted at the front of a motor vehicle. The optical unit 40 consists of an optical unit 42 delimited by a lower face 44. The lower face is intended to be parallel or substantially parallel to the road, when the optical unit 40 is mounted on a motor vehicle. The optical unit 40 comprises an opening closed by a glass 46, protecting the elements present in the optical unit 40 from the external environment, while allowing their observation from outside the optical unit.

According to the invention, the optical box 42 comprises a 2D light module as described above and represented in FIG. 4. The 2D light module is arranged in the optical box so that the large front faces 24 of the light guides are oriented towards the glass 46, so as to be visible through the glass. More precisely, the light guides 4 are positioned in the optical box 42 so that the directions of propagation 18 in the light guides, of the light beams emitted by the first light sources, are perpendicular or substantially perpendicular to the face. bottom 44 of the optical box 42.

Cross sections of the optical block 40, at different heights, are illustrated in FIGS. 6A to 6C. The height of the light guides is defined along a direction parallel to the direction of propagation 18 of the light beams, emitted by the first light sources, in the light guides.

More specifically, FIGS. 6A to 6C represent respectively a cross section of the optical block 40 at the height of the proximal end 8 of the light guides, a cross section of the optical block 40 at mid-height of the light guides and a cross section of the optical unit 40 at the height of the distal end 10 of the light guides. The symbolizes the longitudinal axis of a motor vehicle, passing through the front and rear of the motor vehicle, equipped with the optical unit 40.

As illustrated by FIG. 6A, the 2D light module is positioned in the optical block so that the large front faces 24 of the light guides are oriented towards the center of the roadway, forming with the straight line 48 an angle whose value is of the order of 22°5.

As illustrated by FIG. 6B, at mid-height, the large front faces 24 of the light guides are perpendicular to the line 48. In other words, at mid-height, the large front faces 24 of the light guides face to the road.

At their distal ends 10, the light guides are oriented so that their large front faces form an angle of −22°5 with the straight line 48. In other words, the distal ends of the light guides 4 are oriented in direction of a side of the road.

The optical block 40 illustrated by FIGS. 5 to 6C is thus capable of emitting one or more light beams, of identical or different colors, in accordance with the regulations in force, without resorting to the use of an optical lens or bulky optical reflector. As a result, the optical box 42 is less expensive to produce and less heavy compared to the state of the art. According to another advantage, the dimensions of the optical unit can be reduced in order to facilitate its integration on a motor vehicle, given the fact of the small size of the light module. An optical block according to the invention can thus be more compact compared to the state of the art.

Claims (15)

Light module (2A, 2B, 2C, 2D) for the lighting and/or signaling of a motor vehicle, comprising a light guide (4) extending between a proximal end (8) and a distal end (10 ), the light guide (4) being delimited by two large faces (16) parallel or substantially parallel to each other, a first light source (6) being arranged facing the proximal end (8) of the light guide (4 ), so as to allow the propagation of a light beam between the large faces (16) and along a direction of propagation (18) parallel or substantially parallel to the large faces (16), the light guide (4) comprising diffusing elements, capable of deflecting the light propagating in the light guide (4) in the direction of the large faces (16), characterized in that along the direction of propagation (18), the large faces (16) of the light guide (4) are twisted. Light module (2A, 2B, 2C, 2D) according to claim 1, characterized in that in a plane normal to the direction of propagation (18), the proximal end (8) extends along a first direction elongation (28) and the distal end (10) extends along a second direction of elongation (30), and in that the first direction of elongation (28) forms with the second direction of elongation (30), a torsion angle whose value is between 10° and 60°, preferably between 40° and 50. Light module (2A, 2B, 2C, 2D) according to one of Claims 1 or 2, characterized in that along the direction of propagation (18), the torsion of the large faces (16) is regular. Light module (2A, 2B, 2C, 2D) according to one of Claims 1 to 3, characterized in that the distance separating the proximal end (8) from the distal end (10) of the light guide (4) , is between 60 mm and 120 mm, preferably between 70 mm and 80 mm. Light module (2A, 2B, 2C, 2D) according to one of Claims 1 to 4, characterized in that the smallest distance separating the two large faces (16) is between 2 mm and 5 mm, preferably between 3mm and 4mm. Light module (2B, 2C, 2D) according to one of Claims 1 to 5, characterized in that it comprises a second light source (32), arranged opposite the distal end (10) of the light guide ( 4), so as to allow the propagation of a light beam in the light guide (4), along the direction of propagation (18). Light module (2A, 2B, 2C, 2D) according to one of Claims 1 to 6, characterized in that at least one light source is capable of emitting a light beam of white, red and/or amber color. Light module (2A, 2B, 2C, 2D) according to one of Claims 1 to 7, characterized in that at least one light source comprises several light-emitting diodes (20) arranged along one end of the light guide ( 4). Light module (2A, 2B, 2C, 2D) according to Claim 8, characterized in that at least two light-emitting diodes (20) are capable of emitting light beams of different colours. Light module (2C, 2D) according to one of Claims 1 to 9, characterized in that it comprises an optical reflector (34) positioned opposite a large rear face of the light guide (4) . Optical unit (40) for a motor vehicle, characterized in that it comprises at least one light module (2A, 2B, 2C, 2D) according to one of Claims 1 to 10. Optical unit (40) according to Claim 11, characterized in that the light module (2A, 2B, 2C, 2D) is arranged in the optical unit (40) so that the direction of propagation (18) of the light beam emitted by the first light source (6), either perpendicular or substantially perpendicular to the road when the optical unit (40) is mounted on a motor vehicle, and in that a large front face (24) of at least one light module ( 2A, 2B, 2C, 2D) is visible from outside the optical unit (40). Optical unit (40) according to Claim 11 or 12, characterized in that it comprises at least two light modules (2A, 2B) able to alternately emit light through their large front faces (24). Optical unit (40) according to one of Claims 11 to 13, characterized in that it comprises at least three light modules arranged in the optical unit (40) so that their large front faces (24) are clearly visible from outside the optical unit (40). Optical block (40) according to one of Claims 11 to 14, characterized in that the light module(s) present in the optical block (40) illuminate a surface visible from outside the optical block (40), the surface of which is greater than 50 cm ² .