OLED diode support with elastic connection blades

Abstract

The invention deals with a support for light source(s) for a light module, notably for a motor vehicle, comprising a substrate; at least one surface light source of the organic light-emitting diode type supported by the substrate, the at least one surface light source comprising, at one or more edges, at least two electrical contact zones; electrical tracks deposited on the substrate; and electrical contacts between the electrical contact zones of the light source or sources and the electrical tracks. The electrical contacts comprise elastic blades, in contact under pressure with the contact zone or zones of the surface light source or sources and with the electrical tracks on the substrate.

Claims

1. A support for light source(s) for a light module for a motor vehicle, comprising: a part; a substrate; at least one surface light source, said at least one surface light source being an organic light-emitting diode mounted on said part, said at least one surface light source comprising at least two electrical contact zones; electrical tracks deposited on said substrate; and electrical contacts between said electrical tracks and said at least two electrical contact zones of said at least one surface light source; wherein said electrical contacts comprise elastic blades in contact under pressure with said at least two electrical contact zones of said at least one surface light source and with said electrical tracks.

2. The support according to claim 1, wherein said at least two electrical contact zones of said at least one surface light source in electrical contact with said electrical track forms an angle with said at least two electrical contact zones of said electrical track in contact with said elastic blade, said angle being greater than 30°.

3. The support according to claim 1, wherein each of said elastic blades comprises at least two bent portions, each of said at least two bent portions being in contact with one of said electrical contact zones of said at least one surface light source or with one of said electrical tracks.

4. The support according to claim 1, wherein each of said elastic blades comprises, on at least one of its ends, a generally planar portion suitable for sliding along a guiding surface.

5. The support according to claim 1, wherein said part comprises an added part supporting said elastic blades.

6. The support according to claim 4, wherein an added part comprises said guiding surfaces for planar end portions of said elastic blades.

7. The support according to claim 6, wherein said added part comprises guiding grooves forming said guiding surfaces and receiving said planar end portions of said elastic blades.

8. The support according to claim 5, wherein said added part comprises at least one edge supporting said elastic blades.

9. The support according to claim 8, wherein said added part comprises two edges supporting said elastic blades, said edges extending essentially parallel to one another, said added part comprising a main groove between said edges, said main groove receiving the edge of an extended portion of said substrate.

10. The support according to claim 9, wherein said elastic blades comprise first elastic blades each overlapping exclusively one of said two edges.

11. The support according to claim 10, wherein said first elastic blades have a generally U-shaped profile and ensure an electrical contact between said electrical tracks and said at least two electrical contact zones of said at least one surface light source.

12. The support according to claim 10, wherein said elastic blades comprise second elastic blades, each of said second elastic blades overlapping said two edges and extending through said main groove of said added part.

13. The support according to claim 12, wherein said second elastic blades have a profile comprising two generally U-shaped lateral portions each overlapping one of said two edges and a generally U-shaped central portion, opposite said two generally U-shaped lateral portions.

14. The support according to claim 12, wherein said second elastic blades ensure an electrical contact between said at least two electrical contact zones of said at least one surface light source arranged on either side of said extended portion of said substrate.

15. The support according to claim 5, wherein an edge of an extended portion of said substrate forms a protruding tongue, said electrical tracks on said substrate extending to said tongue, said added part comprising a notch or an opening suitable for receiving said tongue so as to form a space for said tongue to engage with an electrical connector.

16. A light module for a motor vehicle, comprising a support for light source(s) and at least one optical device, wherein said support conforms to claim 1.

17. The support according to claim 2, wherein each of said elastic blades comprises at least two bent portions, each of said at least two bent portions being in contact with one of said electrical contact zones of said at least one surface light source or with one of said electrical tracks.

18. The support according to claim 2, wherein each of said elastic blades comprises, on at least one of its ends, a generally planar portion suitable for sliding along a guiding surface.

19. The support according to claim 3, wherein each of said elastic blades comprises, on at least one of its ends, a generally planar portion suitable for sliding along a guiding surface.

20. The support according to claim 5, wherein said added part comprises the guiding surfaces for planar end portions of said elastic blades.

Description

BRIEF DESCRIPTION OF THE ACCOMPANYING DRAWINGS

(1) FIG. 1 is a perspective view of a light module comprising a light source support according to the invention;

(2) FIG. 2 is an exploded view of the light source support of the module of FIG. 1, the support comprising a substrate and an added part;

(3) FIG. 3 is a detail view of the substrate, of the surface light sources of the OLED type and of the contact blades of the module of FIG. 1;

(4) FIG. 4 is a detail view of the added part of the support of FIG. 2, the added part supporting the contact blades;

(5) FIG. 5 is a view from another perspective of the added part of FIG. 4; and

(6) FIG. 6 is a view of the contact blades.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

(7) FIG. 1 illustrates a light indication module for a motor vehicle. The module 2 is configured to be housed in a casing arranged at the rear of the vehicle. It is configured to ensure a side marker light (or rear light) function, a stop light function and a direction indicator (or flashing) function.

(8) The module 2 comprises a substrate 4 and a part 6 added onto the substrate 4. The added part 6 can be fixed to the substrate 4 by means of screws. The substrate 4 essentially comprises a central part 4.sup.1, two lateral walls 4.sup.2, two front walls 4.sup.3 protruding from the lateral walls 4.sup.2. The two lateral walls 4.sup.2 form a cavity housing light sources (not visible) and a collimator 10 in order to form a light beam for a direction indicator function.

(9) The added part 6 comprises two supports 6.sup.1 and a rear part 6.sup.2. The supports 6.sup.1 are arranged in such a way as to protrude from the central part 4.sup.1 of the substrate 4 essentially opposite one another. Each of these supports 6.sup.1 supports a diode of the OLED type 8. An OLED is a light-emitting diode comprising a superposition of a number of organic semiconductor layers between two electrodes, of which (at least) one is transparent. In this case, these OLED diodes 8 ensure a side marker light function. The rear part 6.sup.2 of the added part 6 is configured to house an electrical power supply connector 14.

(10) The substrate 4 of the module 2 also supports one or more light sources (not visible in FIG. 1 but clearly visible in FIG. 2) between the lateral walls 4.sup.2 and the OLED diodes 8, this or these light source(s) being covered by a collimator 12 in order to ensure a stop light function. More specifically, the rays emitted by these light sources and deflected by the collimator 12 to meet the front face of the corresponding OLED diode 8 and be reflected there toward the front of the module 2.

(11) The longitudinal axis of the module 2 represented in FIGS. 1 and 2 corresponds to its optical axis. This means that the different light beams produced by the module 2 are oriented essentially along this axis. All these beams are preferentially directed toward the front of the module 2 (corresponding to the right in FIG. 1 and to the rear of the vehicle).

(12) The collimators 10 and 12 are parts made of transparent or translucent material, such as glass or polycarbonate (PC). They comprise input and/or output surfaces oriented in such a way as to deflect the rays in a main direction, in application of the Snell-Descartes refraction principle. The input and output faces in effect each form a diopter, namely a surface separating two homogeneous and isotropic transparent media, of different refractive indices. The refractive index of air is in effect of the order of 1 whereas that of glass and of polycarbonate lies between approximately 1.4 and 1.6. The principle of operation of a collimator is well known in itself to those skilled in the art; there is consequently no need to give more detail thereof.

(13) FIG. 2 gives an exploded illustration of the support of the light sources of the module 2. The support comprises the substrate 4 and the added part 6. The substrate 4 comprises, in its central portion, an extended portion 4.sup.4 and a portion 4.sup.5 protruding from the extended portion 4.sup.4. This protruding portion 4.sup.5 is intended to cooperate by engagement with the connector 6 (FIG. 1) for the electrical power supply of the light sources. Electrical tracks 18 are formed on the surface of the substrate 4, continuously from the light sources to the connection portion 4.sup.5. FIG. 2 illustrates the light sources 16 of the LED type arranged on the rear face of the upper side wall 4.sup.2, it being understood that a similar arrangement is provided on the lower side wall, this arrangement not being visible. Light sources (not visible), also of the LED type, are also provided between the two lateral walls 4.sup.2, at the bottom of the cavity formed by the walls. These light sources are also linked electrically by the electrical tracks 18.

(14) The light sources 16 arranged directly on the substrate 4, are thus electrically powered by the electrical tracks 18 extending continuously from the lightsources to the connection portion 4.sup.5.

(15) The presence of electrical tracks 20, the extent of which is limited to the rear edge of the extended portion 4.sup.4, can be seen in FIG. 2. The electrical tracks 20 serve to power the OLED surface light sources 8 (FIG. 1), as will be detailed in relation to the subsequent figures.

(16) The substrate 4, including the connection portion 4.sup.5, is made of plastic material produced by molding and supports the light sources 16 and the electrical tracks 18 and 20, in accordance with the MID (Molded Interconnect Device) technology.

(17) The plastic material of the substrate 4 can be doped with metal particles suitable for ensuring the bonding of the electrical tracks 18 and 20 made of metal material on its outer surface.

(18) The electrical tracks 18 and 20 can be produced by the technology known by the acronym LDS, standing for “Laser Direct Structuring”. This involves passing a laser ray over the corresponding surface of the substrate 4, according to the configuration of the electrical tracks 18 and 20 to be produced. The laser ray has the effect of forming a roughness suitable for favoring the bonding. This step is followed by dip-coating of the substrate 4 in one or more successive metal baths.

(19) Alternatively, or complementarily, the electrical tracks 18 and 20 can be produced by printing of the inkjet type with ink that includes metal particles.

(20) The electrical tracks 18 and 20 can also be produced by a two-step molding of the substrate 4, also called “two-shot molding”. This is an injection molding process using two different resins in which only one of the two resins can be metalized. Typically, the metalizable resin is ABS and the non-metalizable resin is polycarbonate. The substrate 4 is then subjected to an autocatalytic deposition process in which butadiene is used to chemically roughen the surface and allow the adhesion of a primary layer of copper.

(21) Because of the thermoplastic nature of the substrate 4, the use of conventional soldering methods for the electrical contacts is not suitable. The LEDs or light sources 16 are thus fixed mechanically and electrically by application of a glue based on polymer and filled with metal elements. It is thus a so-called “cold” application method that does not damage the substrate 4. After polymerization of the glue, the latter ensures the mechanical and electrical fixing of the LED or light source 16.

(22) FIG. 3 gives a detailed illustration of the electrical connection between the OLED surface diodes 8 and the electrical tracks 20 of the substrate 4.

(23) It can be seen that each of the two surface diodes 8 comprises five electrical contact zones 8.sup.1, 8.sup.2 and 8.sup.3 along their respective edges, these edges being adjacent to the extended portion 4.sup.4 of the substrate 4, on either side of the portion. The two zones 8.sup.1 are situated at the two ends of the edge of the surface diode 8 and are electrically linked, in the surface diode 8, to the cathode, or negative electrode, of the surface diode 8. The two contact zones 8.sup.2 are, within the surface diode 8, linked to a first anode, or positive electrode, while the contact zone 8.sup.3 is, for its part, linked, still within the surface diode 8, to a second anode. The first and second anodes cover different zones of the extent of the surface diode 8 whereas the cathode covers all of the zones of the two anodes. The surface diodes 8 thus exhibit two lighting zones which can be powered independently of one another. It should be noted that this configuration is purely exemplary, given that other configurations can be envisaged.

(24) Still in FIG. 3, the presence of elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3 can also be observed. These elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3 are in reality supported by the added part 6 as will be detailed in relation to FIGS. 4 and 5. The elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3 are provided to ensure a contact with pressure, that is to say that requires neither soldering nor actual mechanical engagement. A first type of elastic contact blade 22.sup.2, 22.sup.3 is provided to ensure an electrical contact between the contact zones 8.sup.2, 8.sup.3 of the surface diodes 8 with the corresponding electrical tracks on the rear edge of the extended portion 4.sup.4. A second type of elastic contact blade 22.sup.1 ensures an electrical link between the two surface diodes 8, more specifically between their zones 8.sup.1 arranged facing, respectively. It should be noted that what is visible for the upper surface diode 8 is also visible for the lower surface diode 8. It should however be noted that, unlike the top face of the extended portion 4.sup.4 of the substrate 4, an electrical track is provided on the bottom face at the rear edge of said portion, level with at least one of the blades 22.sup.1 in order to ensure a grounding of the zones 8.sup.1 of the two surface diodes 8.

(25) The elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3 can be produced from a leaf made of metal material.

(26) FIGS. 4 to 6 illustrate the added part and the elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3.

(27) In FIGS. 4 and 5, it can be seen that the added part 6 comprises, on its front face, two edges 6.sup.3 overlapped by the elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3. The two edges 6.sup.3 extend essentially parallel to one another on either side of a main groove 6.sup.4. The latter is intended to receive the rear edge of the extended portion 4.sup.4 of the substrate 4 (FIGS. 2 and 3). The added part 6 also comprises an orifice 6.sup.5 in the bottom and at the center of the groove 6.sup.4, this orifice 6.sup.5 being intended to receive the connection portion 20 of the substrate 4 (FIGS. 2 and 3).

(28) More particularly with reference to FIG. 5, it can be seen that the added part 6 comprises guiding grooves 6.sup.6, 6.sup.7 and 6.sup.8, these guiding grooves 6.sup.6, 6.sup.7 and 6.sup.8 slidingly receiving the ends of the elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3.

(29) With reference to FIG. 6, it can be seen that each of the elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3 comprises, at both of its ends, generally planar portions 24. It will be observed also that each of the elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3 forms at least two bent portions 26. More specifically, the elastic contact blades 22.sup.2 and 22.sup.3 each have a generally U-shaped profile so as to form the two bent portions 26 and the two planar portions 24. The elastic contact blades 22.sup.2, however, have a flared profile whereas the elastic contact blades 22.sup.3 have a profile whose edges, or even planar portions 24, are generally parallel. The elastic contact blades 22.sup.1 are somewhat different in that their profile comprises two U-shaped lateral portions and a central portion 28 linking the two lateral portions. The central portion 28 extending from the planar portions 26 also forms a U which is, however, generally opposite the U-shapes of the lateral portions. The central portion 28 is intended to be housed in the bottom of the groove 6.sup.4 of the added part 6, as can be seen in FIGS. 4 and 5.

(30) The bent portions 26 of the elastic contact blades 22.sup.1, 22.sup.2 and 22.sup.3 are intended to contact the electrical contact zones 8.sup.1, 8.sup.2 and 8.sup.3 of the surface diodes 8 and the electrical tracks 20 on the substrate 4 (FIGS. 2 and 3).

(31) While the system, apparatus, process and method herein described constitute preferred embodiments of this invention, it is to be understood that the invention is not limited to this precise system, apparatus, process and method, and that changes may be made therein without departing from the scope of the invention which is defined in the appended claims.