Illuminated sign having an electrical cable with a vertical structure

Abstract

The present invention relates to a lighting fixture having a plurality of light sources positioned at the front of a support plate. The light sources each having at least a first and a second electrical terminal. The support plate includes an upper conductive layer and a lower conductive layer. The upper and lower layers are electrically insulated from one another by an intermediate insulating layer, and in that, for each light source, the first and the second electrical terminals are electrically connected respectively to the upper and lower layer, or conversely.

Claims

1. A lighting fixture comprising: a support plate; and a plurality of light sources positioned at the front of the support plate, said light sources each having at least a first and a second electrical terminal, said support plate comprises a glass fiber panel having an upper copper conductive layer and a lower copper conductive layer, said upper and lower layers being electrically insulated from one another by the glass fiber panel operating as an insulating layer, and in that, for each light source, the first and second electrical terminals are electrically connected respectively to the upper copper conductive and lower copper conductive layer, or conversely.

2. The fixture according to claim 1, wherein said support plate includes, for each light source, a first hole opening onto the front of said support plate and traversing at least partially said upper copper conductive layer.

3. The fixture according to claim 2, wherein said first hole is sized to receive said first or second electrical terminal in order to establish an electrical contact point between said light source and said upper copper conductive layer.

4. The fixture according to claim 2, wherein said support plate further comprises at the front a first insulating layer, said upper copper conductive layer being sandwiched between the insulating layer and the first insulating layer, and wherein said first hole traverses said first insulating layer to open onto the front.

5. The fixture according to claim 4, wherein said first hole is sized to receive said first or second electrical terminal in order to establish an electrical contact point between said light source and said upper copper conductive layer, and wherein a first electrical bridge is housed inside said first hole, said first electrical bridge electrically connecting said upper copper conductive layer to the front to establish at the front an electrical contact point between said first or second electrical terminal of said light source and said upper copper conductive layer.

6. The fixture according to claim 5, further comprising fastening means having conductivity properties are used at the level of each of the electrical contact points to secure each of said light sources on said support plate while ensuring electrical conductivity between each of said sources and respectively the upper and lower copper conductive layers.

7. The fixture according to claim 6, wherein the fastening means include an epoxy type conductive adhesive mixed with conductive particles such as for example silver or tin in particular.

8. The fixture according to claim 6, wherein the fastening means include a solder.

9. The fixture according to claim 5, wherein said first electrical bridge is electrically insulated by an insulating sheath.

10. The fixture according to claim 1, wherein said support plate further comprises, for each light source, a second hole opening onto the front of said support plate and traversing said copper conductive upper layer, said insulating layer and at least partially said lower copper conductive layer.

11. The fixture according to claim 10, wherein said support plate has a third, blind, hole, opening onto the front and traversing at least said upper layer and at least partially said insulating layer, said blind hole being substantially centered on said second hole and having a greater diameter than said second hole so as to electrically insulate said upper layer and said second or first electrical terminal electrically connected to the lower layer.

12. The fixture according to claim 10, wherein said second hole is sized to receive said second or first electrical terminal in order to establish an electrical contact point between said light source and said lower copper conductive layer.

13. The fixture according to claim 1, wherein said support plate further comprises at a back a second insulating layer, said lower copper conductive layer being sandwiched between the insulating layer and said second insulating layer.

14. The fixture according to claim 13, wherein said support plate includes, for each light source, a second hole opening onto the front of said support plate and traversing said upper layer, said insulating layer and at least partially said lower copper conductive layer, and wherein a second electrical bridge is housed inside said second hole, said second electrical bridge electrically connecting said lower copper conductive layer to the front to establish at the front an electrical contact point between said second or first electrical terminal of said light source and said lower copper conductive layer.

15. The fixture according to claim 14, wherein said second electrical bridge is electrically insulated by an insulating sheath.

16. The fixture according to claim 1, wherein the first and second electrical terminals of each of the light sources are electrically insulated respectively from the lower and upper copper conductive layers, or conversely.

17. The fixture according to claim 1, further comprising electrical power supply means respectively connected to the upper and lower copper conductive layers to supply each of said light sources with direct current.

18. The fixture according to claim 1, wherein the light sources include at least one LED type light-emitting diode and/or an individual module receiving an SMD LED type light-emitting diode.

19. The fixture according to claim 1, wherein the light sources are positioned according to a defined layout to form a predetermined lighting pattern.

20. The fixture according to claim 1, wherein each light source is presented in the form of an electronic component configured to withstand a voltage of 12 Volts and including an individual LED and a micro-resistor, encapsulated in a resin capsule.

21. A method for manufacturing a lighting fixture having a plurality of light sources positioned at the front of a support plate, each light source having at least a first and a second electrical terminal, said method comprising: providing a support plate comprising an upper copper conductive layer and a lower copper conductive layer, said upper and lower layers being electrically insulated from one another by an intermediate glass fiber panel operating as an insulating layer, and an electrical connection step during which the first and the second electrical terminals of each light source are electrically connected respectively to the upper and the lower copper conductive layers, or conversely.

22. The method according to claim 21, further comprising, prior to the electrical connection step, a first machining step during which said support plate is machined so as to form a first hole opening onto the front and traversing at least partially said upper copper conductive layer.

23. The method according to claim 22, further comprising, prior to the electrical connection step, a second machining step during which said support plate is machined so as to form a second hole opening onto the front and traversing said upper layer, said insulating layer and at least partially the lower copper conductive layer.

24. The method according to claim 23, wherein the electrical connection step includes the use at the level of each of the electrical contact points of fastening means to secure each of said sources on said support plate while ensuring electrical conductivity between each of said sources and respectively the upper and lower copper conductive layers.

25. The method according to claim 23, further comprising a third machining step during which said support plate is machined so as to form a third, so-called blind, hole, opening onto the front and traversing said upper layer and at least partially said insulating layer, said blind hole being substantially centered on said second hole and having a greater diameter than that of the second hole so as to electrically insulate said upper copper conductive layer and said second or first electrical terminal electrically connected to the copper conductive lower layer.

26. The method according to claim 21, wherein the electrical connection step includes the electrical insulation of the first and second electrical terminals of each light source with respectively the lower and upper copper conductive layers, or conversely.

27. A use of a lighting fixture device according to claim 1, for an illuminated sign.

Description

BRIEF DESCRIPTION OF THE APPENDED FIGURES

(1) Further features and advantages of the present invention will emerge from the description hereinafter, with reference to appended FIGS. 2 to 6 which illustrate two embodiment examples thereof which are in no way restrictive and wherein:

(2) FIG. 1a is a first example showing the module method for illuminating a sign, according to the prior art, FIG. 1b is a second example showing the insertion of an LED strip for illuminating a sign, according to the prior art, and FIG. 1c is a third example showing individual LED method for illuminating a sign, according to the prior art.

(3) FIG. 2 represents schematically a cross-sectional view of a lighting fixture having a support plate whereon the LED type light sources are wired according to a first embodiment example of the present invention;

(4) FIG. 3 represents schematically a top view of a lighting fixture having a support plate whereon the LED type light sources are wired according to an embodiment example according to FIG. 2;

(5) FIG. 4 represents a schematic top view of a support plate according to FIG. 2 with no light source;

(6) FIGS. 5A and 5B each represent schematically a cross-sectional view of a lighting fixture having a support plate whereon the LED type light sources are wired according to a second embodiment example of the present invention;

(7) FIG. 6 represents a flow chart of a method for manufacturing a lighting fixture according to an embodiment example of the present invention.

DETAILED DESCRIPTION ACCORDING TO AN ADVANTAGEOUS EMBODIMENT

(8) The manufacture of an illuminated sign according to two embodiment examples will now be described hereinafter with reference collectively to FIGS. 2 to 6.

(9) By way of reminder, one of the aims of the present invention is that of devising an illuminated sign suitable for addressing a problem of producing a custom-made and one-off illuminated shape offering quality lighting, i.e., homogeneous and limiting operating heat.

(10) The two examples described herein will each relate to the design of an illuminated sign; it will be understood however that the invention can be implemented for any lighting or illuminated decoration product, and particularly any lighting fixture which requires a custom-made and one-off shape.

(11) The manufacturing method developed within the scope of the present invention and which will be described hereinafter in the description enables LED type individual light sources to be implemented on a support in an automatable manner.

(12) The term LED source in the general sense will be referred to herein.

(13) The underlying concept of the present invention consists of a manufacturing method aiming to wire all of the light sources 20, herein LEDs, simultaneously by supplying the LED sources by two stacked layers of conductive materials.

(14) In the example described herein, individual LED components suitable for 12 Volts are used, and not 3.3 Volt LEDs as is generally the case on existing signs.

(15) Such a LED component is presented in the form of a resin capsule including the LED per se and a micro-resistor. Such a component is thus configured to withstand a voltage of 12 Volts.

(16) The method used is closest to the individual LED method which enables the best quality product to be obtained in terms of lighting and operating temperature control.

(17) However, unlike this method, each LED source is no longer wired on a horizontal plane thanks to an electric circuit, but on a vertical plane by establishing electrical contact between the two separate conductive layers at two different heights.

(18) In the first embodiment example illustrated in FIG. 2, it is considered to use LED type light sources with conductive rods of different lengths.

(19) In this first example, during an initial supply step S1, a glass fiber panel covered on either side with a conductive plate for example made of copper is obtained.

(20) This is also referred to as a sandwich panel.

(21) Thus, it is understood that the glass fiber panel, which is an insulating material, forms an insulating layer 13 acting as an electrical insulator between an upper conductive layer 11 and a lower conductive layer 12 (the copper plates).

(22) In the second embodiment example illustrated in FIGS. 5A and 5B, it is considered to use SMD LED type light sources with flat electrical terminals.

(23) In this second example, a PCB type multilayer panel is used with as for the first example an intermediate insulating layer 13 acting as an insulating layer between an upper conductive layer 11 and a lower conductive layer 12 and two insulating layers 17 and 18 sandwiching the whole 11-12-13. The layers 12 and 12 are so-called central layers.

(24) This multilayer structure has numerous examples such as for example ensuring an optimal distribution of the electrical load on the two central layers 11 and 12 to be able to wire all of the LEDs without creating hot spots as well as the possibility of creating bands to find the + and the − according to bands on the lower layer.

(25) As illustrated in FIGS. 2 and 5A-5B, the LED sources (or more generally the light sources) will be positioned at the front 10a of the support plate 10, i.e., on the upper layer 11 side.

(26) It is desirable for the two layers 11 and 12 which are at different heights to be electrically connected to one another. More specifically, the two layers 11 and 12 are wired to the same electrical generator 40.

(27) In each of the two examples described herein, a vertical wiring structure is considered wherein the two terminals 21 and 22 of each LED 20 are electrically connected with respectively each of the two layers 11 and 12.

(28) Thus, as illustrated in FIG. 2 or 5, during the manufacturing process, an electrical connection step S5 is considered, during which the first 21 and second 22 electrical terminals of each light source 20 are electrically connected respectively to the upper 11 and lower 12 layers.

(29) To carry out such so-called vertical wiring, the manufacturing method considers beforehand specific machining of the support plate 10.

(30) In the two examples described, the plate will be machined such that each LED source 20 can come into contact with one of the two conductive layers 11 or 12 selectively.

(31) Three machining steps S2, S3 and S4 are particularly considered, which will enable a vertical wiring for each LED source 20 to be designed.

(32) In the two examples described, the use of a CNC type numerical control cutting machine which will machine the support plate 10 specifically is preferably considered.

(33) This CNC machine will be controlled automatically or semi-automatically thanks in particular to a layout generated during a step S0. During this step S0, a computer file readable by the CNC machine will be generated particularly according to the desired shape and various predetermined constraints. This file then contains the layer with particularly the position and the orientation of each LED source.

(34) In each of the two examples described herein, the support plate 10 is therefore machined during a step S2 to form a first hole 14 according to the layout (orientation and position, in particular).

(35) In the example illustrated in FIG. 2, this first hole 14 is machined so as to open onto the front 10a and traverse at least partially the upper layer 11.

(36) In the example described herein, this first hole 14 is moreover sized to receive the first electrical terminal 21, herein the shortest conductive rod.

(37) In the example illustrated in FIGS. 5A and 5B, the terminals 21-22 of the light source 20 are flat. It is considered herein that this first hole 14 is machined so as to open onto the front 10a and traverse at least partially the upper layer 11 and the first insulating layer 17.

(38) Then, the plate is machined during a step S3 to form a second hole 15, again according to the layout.

(39) In the example illustrated in FIG. 2, this second hole 15 is machined so as to open onto the front 10a and traverse the upper layer 11, the insulating layer 13 and at least partially the lower layer 12.

(40) In the example described herein, this second hole 15 is sized to receive the second electrical terminal 22.

(41) In the example illustrated in FIG. 2, this second hole 15 is machined so as to open onto the front 10a and traverse the first insulating layer 17, the upper layer 11, the insulating layer 13 and at least partially the lower layer 12.

(42) Finally, during a step S4 the support plate 10 is machined so as to form a third, so-called blind, hole 16.

(43) As illustrated in FIG. 2 or 5A-5B, this blind hole 16 is machined so as to open onto the front 10a and traverse the upper layer 11 and at least partially the insulating layer 13 (and the first insulating layer 17 for the example in FIG. 5)

(44) In the example described herein, this blind hole 16 is centered on the second hole 15 (coaxial therewith) and has a greater diameter than that of the second hole 15.

(45) The same blind hole 16 is also found in the embodiment example in FIGS. 5A-5B.

(46) These machining operations are repeated according to the layout for each LED source. Thus, it is understood that by producing according to the layout these holes 14, 15 and 16 with different diameters and depths, it is possible to reach the conductive layers 11 and 12 so as to establish an electrical connection with each conductive terminal 21 and 22 of the LED source 20.

(47) The machining of the blind hole 16 enables the longest pole from the lower layer to be insulated.

(48) When positioning the LED sources 20, the holes 14, 15 and 16 produced during the machining operations S2, S3 and S4 are therefore used. The LED sources 20 are then disposed one by one on the support plate 10 at the location defined during machining. The LED sources 20 are therefore positioned upside down so as to have the conductive poles thereof accessible and in contact with the sandwich panel 10.

(49) It will be noted herein that there are numerous LED components compatible with this manufacturing process, all 3 or 5 millimeter diameter through LEDs, but also individual micromodules receiving an SMD type LED.

(50) In the first example described herein and illustrated in FIGS. 2, 3 and 4, the electrical connection S5 is therefore carried out by inserting the first terminal 21 of the source 20 into the first hole 14 (the shortest conductive rod). In this way, an electrical contact point 21a is established between the light source 20 and the upper layer 11.

(51) In this configuration and as illustrated in FIG. 2, it is understood that the first terminal 21 of the LED source 20 is electrically insulated from the lower layer 12.

(52) During the connection S5, the second terminal 22 (the longest conductive rod) of the source 20 is then inserted into the second hole 15 in order to establish an electrical contact point 22a between the light source 20 and the lower layer 12.

(53) Thanks to the diameter of the blind hole 16, the second terminal 22 of the LED source 20 is electrically insulated from the upper layer 11.

(54) At each electrical contact point 21a and 22a (i.e., twice per LED), a drop of conductive adhesive is then deposited during the electrical connection S5.

(55) In the example described herein, an epoxy type adhesive mixed with microparticles of conductive material based on silver or tin for example is used.

(56) Therefore, half of the drops are in contact with the upper layer and the other half are in contact with the lower layer.

(57) Preferably, this adhesive must be prepared with the correct conductivity so as not to oppose an excessively high electrical resistance and with the correct viscosity so as not to move during the procedure.

(58) After applying and drying S6 the adhesive, during a step S7 the two conductive layers 11 and 12 are supplied using electrical power supply means 40 with direct current to supply all the LED sources 20 in parallel.

(59) In the example described herein, the LED sources used are 3.3 Volt LEDs. In this example, it is preferable to supply these two layers with 3.3 Volt direct current.

(60) It is also possible to use LED sources which are directly considered to be supplied with 12 Volts. In this case, this electrical assembly can be supplied directly with 12V.

(61) In the second example described herein and illustrated in FIGS. 5A-5B, the electrical contact points 21a and 22a between the conductive layers 11 and 12 and the source are used by electrical bridges 19a and 19b which are introduced respectively into the first 14 and second 15 holes. Once the bridges 19a and 19b have been introduced into each of the respective holes, a resin is poured into each of said holes 14 and 15. This resin then forms an insulating sheath suitable for ensuring electrical insulation of the bridges.

(62) The electrical contact points 21a and 22a between the terminals of the electrical source 20 and each of the layers 11 and 12 are thus used at the front 10a via the bridges. In this second example, the electrical connection of each of the terminals 21 and 22 of the light source with the layers 11 and 12 is carried out by a solder. Such a solder can be used for example by depositing an addition of material such as soldering paste followed by a passage in a furnace to secure the terminals to the plate.

(63) In each of the examples, the LED sources are then placed on the pre-machined support plate 10 to receive each LED with a predefined position and orientation.

(64) This position and this orientation of the LED sources 20 are defined according to a layout during an initial step S0. Such a layout can be generated automatically with dedicated computer software according to the shape of the desired lighting.

(65) Once the layout has been generated, one or more plates forming a sandwich type panel having on the lower and upper surface thereof a conductive material and an insulating material at the core thereof are prepared. This plate is perforated during the machining to supply the LED sources 20 with the positive or negative conductive layer.

(66) The advantage of further having a first and an example insulating layer sandwiching the whole is that of ensuring an optimal distribution of the electrical load on the two central layers to be able to wire all of the LEDs without creating hot spots. This multilayer configuration also enables bands to be created to find the + and the − according to bands on the lower layer.

(67) Then, drops of conductive adhesive 31 are disposed on the support plate for each contact point 21a and 22a with the LED 20.

(68) The two parts are then assembled to obtain a complete electrical circuit supplying all the LED sources of the shape at once. Each LED is therefore supplied in parallel individually.

(69) The layout of the LEDs consists of disposing imperfect circles in a shape. This part can therefore be the subject of computerized automation supplying the machine with the constraints in respect of spacing with the edge of the shape and spacing between the circles, in other words, between the LEDs.

(70) The layout can therefore be generated electronically automatically or semi-automatically based on the drawing of the shape to be produced.

(71) It is therefore no longer necessary to decide the location of each element such as the modules, the LEDs, or the resistors manually, or to decide the electrical wiring to connect these electrical components to one another.

(72) All of the manufacturing steps described in the section can be automated to a greater or lesser degree. It is therefore possible to benefit from all the advantages of the individual positioning method while reducing the labor to achieve same very considerably.

(73) The automation of this manufacture should enable this production to be located in countries with a high labor cost and therefore bring the production closer to the centers of consumption of this product. This also gives rise to lower shipping costs and shorter lead times.

(74) Finally, the manufacturing method also enables the manufacturing of the signs to be accelerated and therefore have a competitive advantage in terms of production lead time compared to the competition producing these products manually.

(75) It should be observed that this detailed description relates to a specific embodiment example of the present invention, but this description is in no way limiting in relation to the subject matter of the invention; on the contrary, it is intended to remove any imprecision or any incorrect interpretation of the following claims.

(76) It should also be observed that the reference signs placed between parentheses in the following claims are in no way limiting; these signs are solely intended to improve the intelligibility and the comprehension of the following claims as well as the scope of the desired protection.