FR2967235A1 - LIGHTING OR SIGNALING DEVICE FOR A MOTOR VEHICLE HAVING A LIGHT GUIDE RAIL. - Google Patents

Abstract

Lighting or signaling device for a motor vehicle comprising: a light-guiding sheet (1) having an upper face (1a) and a lower face (1b), a rear edge (1c) with at least one lobe, and a output slice (1d); at least one light-emitting diode (3), mounted on a printed circuit board (B), capable of injecting a light beam through one face of the guide sheet, which, by refraction and / or reflection on the faces and on the wafer rearward, gives a substantially parallel beam, emerging through the output wafer (1d); fastening means (F) of the guide ply (1,1 ') in a support (D), which comprise means (S) for clamping the faces (1a, 1b) of the ply between an upper element (6); ) against which bears the upper face (1a) of the web, and a lower part (7) against which bears the lower face (1b), while positioning means (P) are provided between the element lower (7, 7 ', 7 ") and the web (1) and between the various components (6, 12) of the device (A).

Description

LIGHTING OR SIGNALING DEVICE FOR A MOTOR VEHICLE HAVING A LIGHT GUIDE RAIL.

The invention relates to a lighting or signaling device for a motor vehicle of the type of those comprising: a light guide sheet having an upper face and a lower face, generally parallel, a rear edge with at least one lobe, and an output wafer, - at least one light source, of the light-emitting diode type, mounted on a printed circuit board, capable of injecting a light beam by a face of the guide sheet, which, by refraction and / or reflection on the faces and on the rear edge, gives a substantially parallel beam emerging through the output wafer, - fixing means of the guide web in a support.

Devices of this type are known, in particular from document EP 2 169 296 A1. Although such a device is satisfactory, it is desirable to improve the means for fixing the guide ply to maintain the homogeneity of light. output of the sheet, and its optical performance, in particular by avoiding creating a hole opening into the interior of the sheet, or by avoiding creating an attachment appendix on the sheet. Optical surfaces, generally flat surfaces, above and below the sheet, and parabolas at the back of the sheet should be respected, so as not to generate photometric disturbances and especially not to create disturbances at the level of the plane. homogeneity at the output of the optical part that constitutes the sheet. According to the invention, a signaling lighting device for a motor vehicle of the kind defined above is characterized in that: the means for fixing the sheet comprise means for clamping the faces of the sheet between an upper element against which supporting the upper face of the sheet, and a lower part against which bears the lower face, and positioning means are provided between the lower part and the sheet. The signaling lighting device according to the invention may also comprise positioning means between several of its different components, to ensure the appropriate relative positions between these components. The upper element against which abuts the web may be constituted by the printed circuit board disposed above the web. The clamping means may comprise an upper part comprising a front nose which masks the printed circuit board and ends near the web, and clamping means of the upper part and the lower part. Advantageously, the upper part is independent of the lower part, and the clamping means comprise at least one clamping member, provided at the rear of the rear edge, to take the ply between the two pieces. The clamping member may comprise at least one screw. According to one variant, the upper and lower parts form an integral assembly, and determine a slot in which the guide sheet is mounted in a drawer. The lower edge of the slot may comprise at least one elastic blade, in particular horizontal, projecting rearward, forming clamping member. The elastic blade may preferably comprise a housing or pin adapted to cooperate with a pin, or housing, provided under the sheet. Generally, the light source is projecting on the printed circuit board to be placed in line with a light receiving zone, the card comprising, in the vicinity of this reception zone, protruding pins 20 for being applied against the card printed circuit board, when tightening. Pins may also be provided on the web for positioning in two orthogonal directions, corresponding to the transverse direction and the longitudinal direction of a vehicle equipped with the device. The light receiving area may be formed by a frustoconical dome with the small base away from the board. The positioning means, at the level of the web and the lower part, may comprise at least one lug or a housing provided under the lower face of the web, and at least one housing or lug provided on the lower part. The positioning means may also comprise abutment members protruding from the lower part, suitable for bearing against the rear edge of the ply. Preferably, these abutment members bear against the rear edge of the ply, in a hollow between two parabolic lobes. The stop members may be formed by cylindrical studs. A radiator plate may be disposed between the printed circuit board and the top plate. Another object of the invention is a vehicle comprising a lighting and / or signaling device according to the present invention. The invention may include, apart from the arrangements set out above, a number of other arrangements which will be more explicitly discussed below with respect to embodiments described with reference to the accompanying drawings, but which do not are in no way limiting. In these drawings: 1 is an exploded perspective view of a lighting or signaling device according to a first embodiment of the invention. Fig. 2 shows in perspective the assembled device of FIG. 1. 1 o Fig. 3 is a vertical section, on a larger scale, along the line III-III of FIG. 2. Fig. 4 is a vertical section, similar to that of FIG. 3, illustrating an alternative embodiment. Fig. 5 is a partial view from above of the guide ply of FIG. 15 1 disposed on the lower part. Fig. 6 is an exploded perspective view, similar to FIG. 1, an alternative embodiment. Fig. 7 is a section, on a larger scale, along the line VII-VII of FIG. 6 of the assembled device, and FIG. 8 is a perspective front view of the device of FIG. 6 assembled. All expressions of the type "front", "rear", etc., used in the description and the claims are to be understood for a lighting or signaling device attached to a vehicle. Referring to the drawings, particularly Figs. 1, we can see a lighting or signaling device A for a motor vehicle which comprises a guide sheet 1 for the light, in a transparent material, having an upper face 1a and a lower face 1b generally parallel. These faces 1a, 1b in the illustrated example are planar 30 but could have a curved shape as disclosed in EP 1 881 263. The web 1 has a rear slice 1c and an output slice 1d at the front. Device A may be at the front of a vehicle, in which case the output wafer 1d is located in front of the rear wafer 1c in the direction of travel of the vehicle forward. When the device A is disposed at the rear of a vehicle, the output wafer 1d is behind the wafer 1c in the normal direction of travel of the vehicle. The rear slice 1c comprises at least one lobe 2 and, in the present case, several lobes 2, 2.1, 2.2, 2.3, 2.4 convex rearward parabolic contour. As shown in Fig. 3, the vertical section of the slice 1c may be in the form of a dihedral whose tip is turned towards the rear. The lighting device A comprises at least one light source 3, schematically represented in FIG. 3, of the light-emitting diode type, mounted on a PCB printed circuit board disposed, in the examples shown, above the web 1. The light-emitting diode 3 protrudes under the underside of the card B and is adapted to inject a light beam through the upper face of the web 1, which, by refraction and / or reflection on its faces and on the rear edge, gives a substantially parallel beam emerging from the output edge Id. According to the example of FIG. 1, the card B supports four light-emitting diodes arranged below this card and intended to come, when the device A is assembled (see FIG. 3), in line with protuberances 4 in the form of frustoconical domes, of which the small base is turned upwards. The domes 4 are located on the upper face of the sheet 1 for the injection of light into this sheet. The domes 4 (Fig.5) are provided towards the rear edge of the lobes 2.2.1, 2.2, 2.3. Pions 5a are provided in the vicinity of the domes 4 at the upper surface of the web 1 to serve as a support for the printed circuit board B as illustrated in FIG. 3, maintaining a determined distance between each light emitting diode 3 and the upper surface of the dome 4. Lugs 5x, 5y (Fig.5) are also provided on the web 1 for positioning in two orthogonal horizontal directions x, y.

Fastening means F of the guide ply in a support D and means P for indexing and positioning the various components of the device A are provided: to respect the optical surfaces of the guide ply 1, in particular rear parabolas and flat surfaces above, below, 3o - so as not to generate photometric disturbances, - and especially not to create disturbances in the homogeneity at the output of the guide web. For this, according to the invention, it is provided: - not to make holes through the material thickness of the guide web 1; - Do not create appendices, by adding material, to the rear of the guide web 1, in particular at the rear edge 1c and lobes; - Do not add material appendages on the sides of the guide web 1 due to a lack of volume in the associated optical projector and a cost of material at the guide web. The fastening means F of the ply 1 comprise clamping means S of the faces 1a, 1b of the ply between an upper member 6 against which the upper face 1a of the ply bears against a lower piece 7 against which supporting the lower face lb of the web. In the example shown, the upper element 6 is formed by the PCB B circuit. Positioning means P are provided between the lower part 7 and the sheet 1, as well as between the various components of the device i o to ensure appropriate relative positions between the components in the assembled device. The positioning means P, according to the embodiment of Figs. 1-3, comprise, between the lower part 7 and the sheet 1, at least one lug 8 provided under the lower face of the sheet 1 and at least one corresponding housing 9 on the lower part 7 forming support D; the cooperation of the lug 8 and the housing 9 ensures at least the retention of the web 1 forward as shown in FIG. 3. Ribs 10 spaced, obliquely oriented according to the example of FIG. 1, are provided projecting on the upper surface of the lower part 7 to serve as a support for the lower face of the sheet 1, as shown in FIG. 3. The inclination of the ribs 10 with respect to the direction orthogonal to the large dimension of the part 7 is favorable to the demolding of this piece advantageously made of plastic. Each projecting zone, formed by a rib 10, is further away from the rear edge 1c of the ply than the bearing pieces 5a of the upper face of the ply. The positioning means P furthermore comprise, in the example under consideration (see FIG.5), two studs 11 projecting on the upper face of the lower piece 7, at the rear of the latter, suitable for bearing against each other. against the rear edge 1c of the web 1 in a hollow between two parabolic lobes 2, 2.1, 2.3, 2.4. The studs 11 exert the retention towards the rear of the sheet 1 by bearing on the faces of the parabolas. The lighting device may comprise, as illustrated in Figs. 1-3, a radiator 12 in the form of a metal plate, conforming to the outline of the PCB B circuit. Without limitation, the device may comprise thermal screws 6a, 6b screwing into the radiator, to clamp the radiator on the card B. These screws can also serve as a mass for the electronic part.

The positioning means P, for the stacking of the card B and the radiator 12 on the sheet 1, comprise two oblique pins 13 projecting on the upper face of the sheet 1, adapted to engage in oblong openings 14, 15 at the end of the introduction of the card B on the sheet 1, the lower face of the card bears on the pins 5a which determine the position in height. of the web 1, in the vertical direction z. The stud 5x, which may be in the form of a cross, projecting from the upper surface of the sheet 1, is provided to ensure the position in the x direction (direction orthogonal to the longitudinal plane of the vehicle equipped with the lighting device ) of the card B which comprises a conjugated pin 6x projecting under the underside of the card to cooperate with the pin 5x. A pin 6y provided on the card B and projecting below this card can cooperate with the lug 5y, also in the form of a cross, to ensure the stop in the direction y (longitudinal direction of the vehicle on which is installed the lighting device). The upper element of the device A is constituted by an upper part 16 provided forwards with a spout 17 or flange directed downwards. The ply 1 projects forwardly beyond the upper part 6 and the spout 17. According to the embodiment of FIGS. 1-4, the upper part 16 is independent of the lower part 7 and the clamping means S between the two parts comprise two clamping screws 18 adapted to pass through holes 19 provided in the part 16 and able to bear against the edge of a cavity 20 of the upper face of the part 16. As can be seen in FIG. 3, the screws 18 pass through holes 21, 22 respectively provided in the radiator and in the card B to be screwed, preferably by self-tapping, into holes provided in the studs 11. The screws 18 are at the rear of the rear slice 1c of the web and the tightening of these screws makes it possible to take the web in pincers between the lower part 7 and the upper part 16 which exerts its pressure via the radiator 12 and the card B. If necessary, depending on the thermal specificity of the printed circuit board B, the radiator 12 could be omitted. The upper part 16 may comprise in its central front part a window 23 allowing in particular a circulation of air for evacuation of the heat. The spout 17 comes, by its lower part, in the vicinity of the upper face of the ply 1, without exerting a clamping on this sheet. The clearance between the lower part of the spout 17 and the sheet 1 is sufficiently reduced, in particular of the order of 0.2 mm, to mask the inside of the space comprising the plate B and the diodes 3 to the view from the front of the web 1. The clamping means constituted by the screws 18 could be replaced by equivalent means, including clips. If necessary, the upper part 16 could be removed and the screws 18 would directly support the radiator 12 or PCB B circuit in the absence of radiator. Depending on the demolding angle of the guide ply 1, the lug 8 provided under this ply may be sufficient to cooperate with a housing 9 such that the retention of the ply 1 is ensured forwards and backwards. , in which case it is not necessary to provide a stop of the rear edge 1c against pads 11. However, in the case of demolding where the contact surfaces are not blunt, the use of the rear studs 11 is advantageous .

The assembly of the components of the device A illustrated in FIG. 1 results from the foregoing explanations. The sheet 1 is placed on the lower part 7, which serves as a support, being positioned by cooperation of the lug 8 and the housing 9, and by the support of the rear edge of the sheet against the pads 11.

The card B, with the radiator 12, is then installed on the sheet 1 being guided by the oblique pins 13, engaged in the oblong openings 14, 15 of the card and the radiator. The position of the card B is ensured precisely by pressing on the pins 5a, and cooperation of the positioning pins 5x, 5y, and pins 6x, 6y.

Under these conditions, the light-emitting diodes 3 are positioned accurately above the domes 4 of light entry into the sheet. The upper piece 16 is then put in place and fixed with the screws 18 which make it possible to exert the tightening of the faces of the sheet 1 without creating stresses on the sensitive optical surfaces. Referring to Fig. 4, we can see an alternative embodiment of which elements identical or similar to elements already described in connection with Figs. 1 to 3 are designated by the same references without their description being repeated.

According to the variant of FIG. 4, the lower part 7 'has a lug 8' projecting on its upper face, while the ply 1 'has, on its underside, a housing 9' formed by a non-through hole, adapted to receive the lug 8 'with a reduced clearance so that the cooperation of this lug 8' with the housing 9 'ensures retention towards the front and back of the web 1' relative to the lower part 7 '. Retaining studs 11 may, however, be provided at the rear of the ply 1 'as illustrated in FIG. 4, similarly to the embodiment of FIGS. 1-3. The housing 9 'cooperates, according to FIG. 4, with a pin 8 'coming out of the lower piece 7' of support. However, it is possible to stack several guide plies such as the ply 1 'and, in this case, the housing corresponding to the hole 9' of the upper ply can cooperate with a pin io provided on the upper face of a ply lower. It is thus possible to index several stacked guiding layers. As in the example of Figs. 1-3, the guide ply 1 'of FIG. 4 is gripped between the lower support piece 7 'and the upper part 16 with the interposition of the printed circuit board B and, if appropriate, the radiator 12. Referring to FIGS. 6 to 8, we can see an alternative embodiment of the lighting device according to which the upper piece 16 "and the lower piece 7" are in one piece and form an assembly piece 24 by determining a slot 25 in which the guide web 1 can be mounted in a drawer and engaged from the rear to the front. The lower edge of the slot 25 comprises, according to the example of FIG. 6, two horizontal resilient blades 26, spaced transversely, projecting rearwardly. Each blade 26 comprises a hooking member constituted by a hole 27 in the example of FIG. 7 adapted to cooperate with a complementary member, namely a pin 28 provided under the sheet 1. The opposite arrangement is possible according to which the pin is provided projecting on the blade 26 and the housing would be provided in the sheet 1 as illustrated on Fig. 4. The resilient blades 26 furthermore form a clamping member of the ply 1 against the upper part 16 "of the part 24, with the interposition of the printed circuit board B and possibly a radiator 12. According to this variant of Fig. 6 to 8, it is no longer necessary to provide clamping screws such as those of the preceding figures, the clamping being ensured by the elastic blades 26. The construction is simplified since the part 24 groups the lower and upper parts together. only one set.

Whatever the embodiment adopted, the lighting device according to the invention makes it possible to index and fix the optical part constituted by the guide ply 1, 1 'while keeping the homogeneity of light at the output of the pieces. optical and optical performance, without creating holes opening into sensitive areas inside the room, and without creating attachment appendages on the optical part. The proposed device allows: - to remove "black holes" in the light output portion of the optical part (guide sheet) that would be due to screw passages in the thickness of the material of the optical part; - Avoid appendages for attachment to the back of the optical part, which would significantly reduce the optical performance of the room if they were provided at the back of the dishes; avoid appendages for fixing at the end of the optical part that would take volume in the projector; to have very weak peripheral games around the optical part, in particular in the solution of FIGS. 1 to 4.

Claims (15)

REVENDICATIONS1. Lighting or signaling device for a motor vehicle comprising: - a light-guiding layer (1,1 ') having an upper face (1a) and a lower face (1b), a rear edge (1c) with at least one lobe, and an output wafer (Id), - at least one light source, of the electroluminescent diode type (3), mounted on a printed circuit board (B), capable of injecting a light beam through one face of the guidance, which, by refraction and / or reflection on the faces and on the rear edge, gives a substantially parallel beam, emerging by the output wafer (Id), - fixing means (F) of the guide ply (1). , 1 ') in a support (D), characterized in that: - the fastening means (F) of the web comprise clamping means (S) of the faces (la, 1b) of the web between an upper element (6, B) against which bears the upper face (1a) of the sheet, and a lower piece (7) against which bears against the lower face (lb), and positioning means (P) are provided between the lower piece (7, 7 ', 7 ") and the sheet (1,1'). 2. Device according to claim 1, characterized in that the upper element (6) against which abuts the web (1, 1 ') is constituted by the printed circuit board (B) disposed above the table (1, 1 '). 3. Device according to claim 1 or 2, characterized in that the clamping means (S) comprise an upper piece (16, 16 ") having a front nose (17, 17") which hides the circuit board (B). printed and ends close to the web (1), and clamping means (S) of the upper piece (16, 16 ") and the lower piece (7.77"). 4. Device according to claim 3, characterized in that the upper part (16) is independent of the lower part (7, 7 '), and the clamping means 35 (S) comprise at least one clamping member (18) , provided at the rear of the rear slice (1c), to take the web (1) pinced between the two parts (7, 7 ', 16). 2967235 He 5. Device according to claim 4, characterized in that the clamping member comprises at least one screw (18). 5 6. Device according to any one of claims 1 to 3, characterized in that the upper (17 ") and lower (7") parts form an assembly (24) in one piece, and determine a slot (25) in which the guide web (1) is mounted in a drawer. 10 7. Device according to claim 6, characterized in that the lower edge of the slot (25) comprises at least one resilient blade (26), in particular horizontal, projecting rearwardly, forming clamping member. 8. Device according to claim 7, characterized in that the elastic blade 15 (26) comprises a housing (27) or pin adapted to cooperate with a pin (28), or housing, provided under the sheet. 9. Device according to any one of the preceding claims, characterized in that the light source (3) is projecting on the printed circuit board (B) to be placed in line with a light receiving area (4). ), the card having in the vicinity of this zone of receiving pins (5a) projecting to be applied against the PCB (B) of the printed circuit, during tightening. 10. Device according to claim 9, characterized in that lugs (5x, 5y) 25 are also provided on the web (1,1`) for positioning in two orthogonal directions (x, y) corresponding to the transverse direction and in the longitudinal direction of a vehicle equipped with the device. 11. Device according to any one of the preceding claims, characterized in that the positioning means (P) at the web (1,1 ') and the lower part (7,7', 7 ") comprise at least one lug (8,28) or a housing (9 ') provided under the underside of the web, and at least one housing (9,27) or lug (8') provided on the lower part (7,7 '). 12. Device according to any one of the preceding claims, characterized in that the positioning means (P) comprise stop members (11) projecting from the lower piece (7, 7 ') adapted to abut against the rear slice (1c) of the sheet. 13. Device according to claim 12, characterized in that the abutment members are in abutment against the rear edge (1c) of the web, in a hollow between two parabolic lobes. 14. Device according to any one of the preceding claims, characterized in that a radiator plate (12) is disposed between the printed circuit board (B) and the upper plate (16). 15. Motor vehicle comprising a device according to any one of the preceding claims.