COMPACT LIGHTING DEVICE PROVIDING EVEN LIGHTING

Abstract

A lighting device (ED), for example for a seat, comprises: - a housing (BD) containing a photon-generating light source (SP) and a flat light guide (GL) with a first rear face (FR1) receiving the generated photons, a first front face (FV1) emitting these received photons, and a concave central portion (PCG), projecting from the first rear face (FR1), generally semi-conical in shape, receiving the generated photons and spatially distributing the delivered photons at the first front face (FV1), and - a diffusion screen (ED) positioned opposite the first front face (FV1), fixedly attached to the housing (BD) and designed to diffuse the photons emitted by the first front face (FV1) homogeneously. Figure 3

Description

Title of the invention: COMPACT LIGHTING DEVICE PROVIDING EVEN LIGHTING Technical field of the invention

[0001] The invention relates to lighting devices comprising at least one housing containing a source capable of generating photons and a light guide. State of the art

[0002] In certain technical fields, such as that of vehicles (possibly automobiles), lighting devices are used to illuminate an area by backlighting. By way of example, and as described in document DE-U1 20 2023 102 747, such a lighting device can be installed in the backrest of a motor vehicle seat in order to backlight an area of ​​the seat cover.

[0003] Some of these lighting devices comprise a housing containing a photon-generating source and a light guide having a rear face for receiving the generated photons and a front face for emitting these received photons. One drawback of this type of lighting device is that the front face of the light guide generally emits the photons unevenly (i.e., with an unsatisfactory spatial distribution), and therefore the area associated with the lighting device is not uniformly illuminated. This can be perceived by an observer as a design or operational defect, and thus detracts from the perceived quality. Another drawback of this type of lighting device is that it is generally bulky and therefore cannot be used in already crowded or small spaces.

[0004] The invention therefore aims in particular to improve the situation. Presentation of the invention

[0005] In particular, it proposes for this purpose a lighting device comprising a housing containing a source suitable for generating photons and a light guide having a first rear face suitable for receiving the generated photons and a first front face suitable for delivering these received photons.

[0006] This lighting device is characterized by the fact that:

[0007] - that its light guide is of the flat type and includes a concave central part, protruding on its first rear face, generally semi-conical in shape, receiving the generated photons and designed to spatially distribute the photons delivered at the level of the first front face, and

[0008] - that it also includes a display screen placed opposite the first face front of the light guide, fixedly attached to the housing and designed to diffuse homogeneously the photons delivered by this first front face.

[0009] Thanks to the invention, the lighting device has a significant compactness allowing it to be installed in a space that is already cluttered or small in size, and allows the associated area to be backlit homogeneously, and thus to reinforce the impression of quality.

[0010] The lighting device according to the invention may include other features which may be taken separately or in combination, and in particular:

[0011] - its display screen may include a second rear face placed opposite of the first front face of the light guide, and curved;

[0012] - in the presence of the first option, the bulging of the second rear face of the broadcast screen may have a center which is located on the axis of a center of the concave central part;

[0013] - the central part of the light guide may include a flat rear end and circular;

[0014] - its housing may include first fastening elements adapted to cooperate with secondary fixing elements which include equipment in order to securely attach the lighting device to the latter.

[0015] The invention also proposes a seat suitable for equipping a vehicle and comprising a lighting device of the type presented above.

[0016] For example, this seat may include a headrest within which the lighting device is installed opposite an area to be backlit. In this case, the headrest may, for example, include, in a lower part comprising this area, a heating device designed to draw in warm air and to which the lighting device is permanently attached.

[0017] The invention also proposes a vehicle, possibly of the automobile type, and comprising at least one seat of the type presented above. Brief description of the figures

[0018] Other features and advantages of the invention will become apparent from an examination of the detailed description below, and the accompanying drawings (mostly obtained using CAD / CAM (“Computer-Aided Design / Computer-Aided Manufacturing”)), in which:

[0019] [Fig-1] illustrates schematically and functionally, in a cross-sectional view in a longitudinal and vertical plane, part of an example vehicle comprising a seat having a headrest equipped with a heating device to which a lighting device according to the invention is attached,

[0020] [Fig.2] schematically illustrates, in a perspective view from the front side, an example of an embodiment of a lighting device according to the invention, fully assembled,

[0021] [Fig.3] schematically illustrates, in a perspective view, the different elements of the lighting device of [Fig.2], before they are assembled together, and

[0022] [Fig.4] schematically illustrates, in two different perspective views, the light guide of the lighting device of figures 2 and 3. Detailed description of the invention

[0023] The invention aims in particular to provide a compact and suitable DE lighting device to ensure homogeneous lighting of a ZA zone.

[0024] In what follows, it is considered, by way of non-limiting example, that the DE lighting device is intended to equip a seat SV of a motor vehicle V, such as a car. However, a DE lighting device according to the invention can equip any equipment in a vehicle, and in particular a dashboard or a side door. Furthermore, a DE lighting device according to the invention can equip any type of vehicle (land, sea (or river), or air), an electrified building, an electrified installation (possibly industrial), or an electrified device or system, provided that there is a small area to be backlit.

[0025] Furthermore, in the preceding and following text, the terms "front" and "rear" are defined with respect to the front end of the DE illumination device through which the photons exit. Consequently, the front part of an element is located closer to the front end of the DE illumination device than the rear part of that same element.

[0026] A part of an example vehicle V comprising a seat SV having a lighting device DE according to the invention has been schematically illustrated in [Fig.1].

[0027] It should be noted that in the example illustrated, but not limited to, in [Fig. 1], the lighting device DE is installed inside a headrest AT attached to the seat back SV, opposite a zone ZA to be backlit. For example, this zone ZA of the headrest AT may include the vehicle brand logo V. However, the lighting device DE could also be installed inside the seat back SV (in front of a backlit area, for example, of the seat cover).

[0028] As illustrated at least partially in Figures 2 and 3, a lighting device DE, according to the invention, comprises at least a housing BD, a photon source SP, a light guide GL and a diffusion screen ED.

[0029] The BD housing accommodates the SP photon source and the GL light guide in order to protect them at least partially.

[0030] It should be noted, as illustrated in Figures 2 and 3, that when the housing BD does not include a rear wall enclosing it, the illumination device DE may also include a rear cover CR designed to close it in order to completely protect the rearmost photon source SP. In this case, the housing BD and the rear cover CR may respectively include first coupling elements EC1 and second coupling elements EC2 designed to cooperate in order to secure them to each other. For example, and as illustrated in Figures 2 and 3, the first coupling elements EC1 may be clipping tabs, each with a clipping hole, and the second coupling elements EC2 may be clipping notches designed to be housed in, and retained by, these clipping holes.

[0031] The photon source SP is arranged to generate photons for the light guide GL.

[0032] For example, this SP photon source may include at least one light-emitting diode (or LED). But alternatively, it could include at least one laser diode or a gas laser, for example.

[0033] Also, for example, and as illustrated non-limitingly in [Fig. 3], the photon source SP and the electronic components and / or circuit(s) for controlling the power supply and operation of this photon source SP may be part of a CE electronic board housed in the BD casing and / or in the optional rear cover CR. Also, for example, this CE electronic board may be a printed circuit board of the PCB type ("Printed Circuit Board").

[0034] As illustrated in Figures 3 and 4, the light guide GL is flat and comprises opposing first rear face FRI and first front face FV1. The first rear face FRI is designed to receive the photons generated by the photon source SP. The first front face FV1 is designed to deliver the photons received by the first rear face FRI. Furthermore, the light guide GL includes a central concave portion PCG projecting from (on the side of) its first rear face FRI, having a generally semi-conical shape. The PCG therefore includes a rear end ER, oriented towards (and closest to) the first front face FV1, which receives the photons generated by the photon source SP, and is designed, due to its arrangement (semi-conical shape), to spatially distribute the photons it delivers from the first front face FV1.It will be understood that the central part PCG being concave, it therefore includes a hollow part PC downstream of its rear end ER, as illustrated in [Fig.4].

[0035] This arrangement of the central PCG part advantageously allows obtaining the spatial distribution of the delivered photons over a very small distance.

[0036] For example, and as illustrated without limitation in Figures 3 and 4, the rear end ER of the central part PCG may be flat and circular. But this is not mandatory.

[0037] As illustrated at least partially in Figures 2 and 3, the diffusion screen ED is fixedly attached to the housing BD and comprises opposing second rear face FR2 and second front face FV2. The second rear face FR2 is positioned opposite the first front face FV1 of the light guide GL. The second front face FV2 is the face through which the guided photons exit the illumination device DE. This diffusion screen ED is designed to diffuse homogeneously, at its second front face FV2, the photons delivered by the first front face FV1 of the light guide GL.

[0038] Thanks to its particularly original design, the DE lighting device is now significantly more compact, allowing it to be installed in already crowded or small spaces. It also provides homogeneous backlighting of the associated ZA zone (and therefore with virtually the same intensity everywhere), which enhances the impression of quality and can introduce elegance and / or personalization. Furthermore, this backlighting of the ZA zone can, when the ZA zone includes the vehicle brand logo V, reinforce the brand identity.

[0039] For example, and as illustrated, but not limited to, in [Fig. 3], the second rear face FR2 of the diffusion screen ED (positioned opposite the first front face FV1 of the light guide GL) can be curved (or convex). This promotes the spatial distribution of photons in the presence of the concave central part PCG of the light guide, which transmits the photons to it, and thus promotes the homogeneity of the illumination of the ZA area.

[0040] Also, for example, and as illustrated, but not limited to, in [Fig. 3], the bulge of the second rear face FR2 of the ED diffusion screen can have a center located on the axis of the center of the central part PCG. This further promotes the spatial distribution of photons, and thus further enhances the homogeneity of the illumination of the ZA zone.

[0041] In order to obtain perfect alignment of the center of the central part PCG and the center of the bulge of the second rear face FR2, the diffusion screen ED can, for example and as illustrated non-limitingly on [Fig.3], include, on the side of its second rear face FR2, three positioning tabs PP respectively provided with notches defining notches intended to be housed in corresponding housings L of the light guide GL.

[0042] Also, for example, and as illustrated without limitation in Figures 2 and 3, the ED diffusion screen and the BD housing may respectively comprise The third (EC3) and fourth (EC4) coupling elements are designed to cooperate and secure each other. For example, and as illustrated (though not limited to) in Figures 2 and 3, the third (EC3) coupling elements can be clipping tabs, each with a clipping hole, and the fourth (EC4) coupling elements can be clipping notches designed to fit into, and be held in place by, these clipping holes. However, other coupling methods are possible, including screws that engage with threaded holes.

[0043] Also, for example, and as illustrated non-limitingly in Figures 2 and 3, the housing BD may include first fixing elements EF1 adapted to cooperate with second fixing elements (not illustrated) of a piece of equipment in order to fix the lighting device DE to the latter.

[0044] It should be noted that in the example illustrated, but not limited to, in [Fig. 1], the headrest AT includes, in a lower part comprising zone ZA, a heating device (or equipment) AC designed to draw warm air towards the neck of a person seated on the seat SV and to which the lighting device DE is fixedly attached by means of the first EF1 and second fixing elements. However, the lighting device DE could be fixedly attached to the structural part of the headrest AT, or be press-fitted into a dedicated recess defined in the foam of the headrest AT.

[0045] It should also be noted that the ZA area to be backlit may optionally be part of the AC heating appliance (or equipment), as illustrated, but not limited to, in [Fig. 1]. However, this is not mandatory. Indeed, the ZA area could be located directly above the AC heating appliance (or equipment).

[0046] It should also be noted that in the example illustrated, but not limited to, and at least partially, in Figures 2 and 3, the first fastening elements EF1 may include clipping tabs, two of which have a clipping notch and the last one has a clipping hole. In this case, the second fastening elements of the equipment (here, the AC heater) may include clipping tabs, two of which have a clipping hole and the last one has a clipping notch.

[0047] It should also be noted that the light guide GL can, for example, be made of polymethyl methacrylate (or "PMMA"). It should also be noted that the diffusion screen ED can, for example, be made of polycarbonate (or PC), and more preferably of "TARFLON" PC (registered trademark), which promotes photon diffusion. It should also be noted that the housing BD can, for example, be made of polypropylene (or PP). It should also be noted that the optional rear cover CR can, for example, be made of polyethylene terephthalate (or PBT).

Claims

Demands

1. Lighting device (ED) comprising a housing (BD) housing a source (SP) suitable for generating photons and a light guide (GL) having a first rear face (FRI) suitable for receiving said generated photons and a first front face (FV1) suitable for delivering these received photons, characterized in that said light guide (GL) is of the flat type and includes a concave central part (PCG), projecting on its first rear face (FRI), of generally semi-conical shape, receiving said generated photons and suitable for spatially distributing said delivered photons at the level of said first front face (FV1), and in that it further comprises a diffusion screen (ED) placed opposite said first front face (FV1), fixedly attached to said housing (BD) and suitable for homogeneously diffusing said photons delivered by said first front face (FV1).

2. Lighting device according to claim 1, characterized in that said diffusion screen (ED) comprises a second rear face (FR2) placed opposite said first front face (FV1), and curved.

3. Lighting device according to claim 2, characterized in that the bulge of said second rear face (FR2) has a center which is located in the axis of a center of said central part (PCG).

4. Lighting device according to any one of claims 1 to 3, characterized in that said central part (PCG) comprises a flat and circular rear end (ER).

5. Lighting device according to any one of claims 1 to 4, characterized in that said housing (BD) includes first fixing elements (EF1) adapted to cooperate with second fixing elements included in equipment (AC) in order to fix said lighting device to the latter.

6. Seat (SV) suitable for equipping a vehicle (V), characterized in that it comprises a lighting device (DE) according to any one of claims 1 to 5.

7. Seat according to claim 6, characterized in that it comprises a headrest (AT) inside which is installed said lighting device (DE) opposite an area (ZA) to be illuminated by backlighting.

8. Seat according to claim 7, characterized in that said headrest (AT) comprises, in a lower part comprising said zone (ZA), a heating device (AC) adapted to draw in hot air and to which said lighting device (DE) is fixedly attached.

9. Vehicle (V), characterized in that it comprises at least one seat (SV) according to any one of claims 6 to 8.

10. Vehicle according to claim 9, characterized in that it is of the automobile type.

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