EP2093483B1 - Lighting unit for vehicle imitating LEDs and comprising a light shield - Google Patents

Abstract

The unit (FA) has a screen (EC) including a diffusion element (LD) and placed in front of a light source (S) e.g. lamp, housed in a case (B), where a mask (MA) is placed in front of the screen. The mask has a functional hole (TF1) associated with the element and a non-functional hole (TN1) placed at a side of the functional hole. An occultation element (EO) i.e. planar flexible joint, is installed between the case and the mask behind the non-functional hole, and prevents light issued from the source from passing by the non-functional hole, where the element is made of synthetic rubber.

Description

The invention relates to motor vehicle light units.

• un boîtier, logeant au moins une source de lumière, un écran muni d'éléments de diffusion et placé devant la source de lumière, et un masque, généralement métallisé (par exemple chromé), placé devant l'écran et muni de trous associés aux éléments de diffusion, et
• une glace placée devant le masque.

As known to those skilled in the art, certain motor vehicle light units, and in particular those located at the rear (called rear traffic lights), consist of an assembly of elements comprising:

• a housing, housing at least one light source, a screen provided with diffusion elements and placed in front of the light source, and a mask, generally metallized (for example chromed), placed in front of the screen and provided with holes associated with the diffusion elements, and
• an ice cream placed in front of the mask.

This type of optical block, which is described in particular in the patent document FR 2808247 , is intended to provide at the mask a so-called LED (light-emitting diode (or LED)) effect which is similar to that provided by LEDs, but using a traditional light source (such as a lamp (or bulb)) instead of the LEDs.

The photometry that a "lamp plus mask" system must respect is fixed by the number of holes of the mask, called functional, which are sufficient to diffuse the light of the lamp. Since this photometry may vary from one optical block model to another, it will be understood that certain holes of the mask may be non-functional (that is to say, useless to the definition of photometry). In other words, the number of functional holes and the number of non-functional holes (intended to give a stylistic effect) vary from one optical block model to another. However, when the lamp plus mask system does not perform its function (and therefore the lamp is off), the color that is perceived at the functional holes is substantially different from that perceived at the non-functional holes. which is detrimental to the style of the function.

The invention therefore aims to improve the situation.

It proposes for this purpose an optical unit intended to be part of a motor vehicle and comprising i) a housing housing at least one light source, a screen provided with a number N of diffusion elements and placed in front of the source of light, and a mask placed in front of the screen and provided with M functional holes respectively associated with at least some of the diffusion elements and K non-functional holes placed next to the functional holes, and ii) an ice placed in front of the mask.

N is greater than or equal to 1, and preferably greater than or equal to 2. K is greater than or equal to 1, and preferably greater than or equal to 2. M is less than or equal to N, greater than or equal to 1, and preference greater than or equal to 2.

This optical block is characterized in that it furthermore comprises at least one occulting element installed between the housing and the mask, behind the non-functional holes, and arranged in such a way as to prevent the light which comes from the source of the go through the non-functional holes.

According to the invention, there is also provided a motor vehicle optical unit comprising: i) a housing housing at least one light source, a screen provided with several diffusion elements and placed in front of said light source, and a mask placed in front of said light source; screen and provided with several holes, at least some of which are respectively associated with at least some of said diffusion elements, and ii) an ice placed in front of said mask, characterized in that it further comprises at least one occulting element installed between said housing and said mask behind only some of said holes and arranged to prevent light from said source from passing through these obscured holes.

• son élément d'occultation peut présenter une couleur qui est sensiblement identique à la couleur que présente la glace devant le masque ;
• son élément d'occultation peut être un joint souple sensiblement planaire, par exemple réalisé en caoutchouc synthétique ;
• le nombre N d'éléments de diffusion peut être égal au nombre M de trous fonctionnels. Dans ce cas, l'élément d'occultation peut être installé à côté de l'écran ;

• dans une variante, le nombre N d'éléments de diffusion peut être égal à la somme du nombre M de trous fonctionnels et du nombre K de trous non fonctionnels. Dans ce cas, l'élément d'occultation peut être installé entre le boîtier et l'écran derrière les éléments de diffusion qui sont associés aux trous non fonctionnels ;
• son boîtier peut comprendre, sur une face interne, au moins deux plots propres à immobiliser l'élément d'occultation dans sa position d'occultation de lumière ;
• le nombre M de trous fonctionnels peut être égal à 6 et le nombre K de trous non fonctionnels peut être égal à 4.

The optical block according to the invention may comprise other characteristics that can be taken separately or in combination, and in particular:

• its occulting element may have a color that is substantially identical to the color that the ice in front of the mask;
• its occulting element may be a substantially planar flexible seal, for example made of synthetic rubber;
• the number N of diffusion elements may be equal to the number M of holes functional. In this case, the concealment element can be installed next to the screen;

• in a variant, the number N of diffusion elements may be equal to the sum of the number M of functional holes and the number K of non-functional holes. In this case, the concealment element can be installed between the housing and the screen behind the diffusion elements that are associated with the non-functional holes;
• its housing may comprise, on an internal face, at least two pads adapted to immobilize the occulting element in its light occultation position;
• the number M of functional holes may be equal to 6 and the number K of non-functional holes may be equal to 4.

• la figure 1 illustre schématiquement, dans une vue en perspective, un exemple de réalisation de bloc optique arrière selon l'invention, avant assemblage,
• la figure 2 illustre schématiquement l'écran et un élément d'occultation installés dans le boîtier de l'exemple de bloc optique de la figure 1, et
• la figure 3 illustre l'exemple de bloc optique de la figure 1, une fois assemblé.

Other features and advantages of the invention will appear on examining the detailed description below, and the attached drawings, in which:

• the figure 1 illustrates schematically, in a perspective view, an embodiment of a rear optical unit according to the invention, before assembly,
• the figure 2 schematically illustrates the screen and a concealment element installed in the housing of the optical block example of the figure 1 , and
• the figure 3 illustrates the optical block example of the figure 1 once assembled.

The attached drawings may not only serve to complete the invention, but also contribute to its definition, if any.

We have schematically represented on the figure 1 an embodiment of an optical unit FA according to the invention, before assembly, intended to equip a motor vehicle. In this non-limiting example, the FA optical unit is a signal rear light intended to be installed in the rear of a motor vehicle. But, the invention is not limited to this type of implantation. It also relates to certain optical units intended to be installed at the front of a motor vehicle.

Such an optical unit (rear) FA comprises a housing B secured to the front side to an ice (front) G and possibly the back side to what the man of the art calls a "lamp holder" PL. The latter (PL) serves as a support for at least one light source S, such as a lamp (or bulb). In the non-limiting example illustrated on the figure 1 , the lamp holder PL supports in its upper part a lamp which does not participate in the invention, and in its lower part a lamp S which is part of what the man of the art sometimes calls the "lamp system plus mask Object of the invention.

It is recalled that a lamp plus mask system is intended to provide a predetermined function of a predetermined photometry within an optical unit FA while providing an effect of light emitting diodes (or LEDs (or LEDs)). These functions include the reversing light (white), the flashing light (orange), and the stop light (red).

The casing B houses (on the front side, that is to say on the side of its inner face FI) an EC screen, at least one occulting element EO and a mask MA.

In the nonlimiting exemplary embodiment illustrated on the figure 1 , the housing B is intended to house a single occulting element EO. However, the invention is not limited to this number of EO occultation elements, as will be seen below. It applies in fact to FA optical blocks comprising at least one occultation element EO.

As is best illustrated on the figure 2 , the screen EC is installed in the housing B so as to be placed in front of the light source S. It comprises a number N (N≥2) of diffusion elements LD. Each diffusion element is in the form of a diffusion lens or a prism for diffusing a portion of the light that the light source S emits towards the ice G (that is to say the front (which here corresponds to the rear vehicle)). The LD diffusion elements are arranged to contribute to the photometry of the function which is provided by the lamp system plus mask of the optical block FA.

This screen EC may for example be a molded part made of a material such as polycarbonate (or PC).

In the nonlimiting exemplary embodiment illustrated on the figure 2 , the EC screen has ten LD distribution elements. However, the invention is not limited to this number N = 10 of diffusion elements LD. It concerns indeed any EC screen comprising at least one (N≥1) diffusion element LD.

Moreover, in the nonlimiting exemplary embodiment illustrated on the figure 2 the four rightmost DL diffusion elements are not completely surrounded by matter. This is intended to facilitate and / or improve the occultation of the light by the occulting element OE, as will be seen later. In addition it reduces the weight of the EC screen.

Finally, in the nonlimiting exemplary embodiment illustrated on the Figures 1 and 2 , the EC screen comprises an upper part placed above the LD diffusion elements. This upper part is intended to contribute to another function of the optical block FA together with the lamp which is located above the lamp S of the lamp system plus mask on the lamp holder PL. It will be understood that this upper part may not exist. It will also be understood that the screen EC may possibly comprise a lower part placed below the diffusion elements LD.

As illustrated on the figures 1 and 3 , the mask MA is installed in the housing B so as to be placed in front of the screen EC and behind the glass G. It comprises, on the one hand, a number M (with M≤N and M≤1) of holes ( or so-called functional windows TFm (m = 1 to M) associated respectively with at least some of the diffusion elements LD, and secondly, a number K (with K≤1) of so-called non-functional holes (or windows) TNk (k = 1 to K) placed next to the functional holes TFm.

Here, the term "functional hole" means a hole (or window) which is associated with a diffusion element LD which contributes to the photometry of the function which is provided by the lamp plus mask system of the optical unit FA, and which thereby also contributes to this function. Another way of expressing things is to say that the functional holes are those which will remain unobstructed during the setting up of the occultation element, while the non-functional holes are those which will become obscured during setting up the occulting element. The choice between the holes that we will hide and those that we will not hide depends on the desired photometry, for example light anywhere or only on one side, or the whole realizing this or that bright pattern rather than another.

Moreover, here "non-functioning hole" is understood to mean a hole (or window) that is not associated with a diffusion element LD or that is associated with a diffusion element LD that does not contribute to the photometry of the function which is ensured by the lamp system plus mask of the optical block FA, and which therefore does not contribute to this function. It will be understood that N may be equal to M + K (as in the nonlimiting example illustrated), but that one can also have N = M. The non-functional holes TNk are therefore used for the style, it is that is to say to participate in the effect of LEDs.

Finally, the term "hole associated with a diffusion element LD" here refers to a hole (or window) TFm or TNk which is placed in front of a (or opposite to) a diffusion element LD or which houses at least a part of an LD diffusion element (as is the case in the nonlimiting example illustrated in FIG. figure 3 ).

In the nonlimiting exemplary embodiment illustrated on the Figures 1 to 3 the mask MA comprises six functional holes (or windows) TFm (TF1 to TF6, m = 1 to 6, M = 6) and four non-functional holes (or windows) TNk (TN1 to TN4, k = 1 to 4, K = 4). Of course, many other combinations can be envisaged as long as one has N≥1, M≤N (with M≥1), and K≥1.

The mask MA is preferably metallized (for example chromed), at least partially, in particular on its front face which is intended to be observed from outside the vehicle and on reflective portions at least partially defining the holes (or windows) TFm and TNk. It will be understood that the shape of the mask M depends on how the diffusion elements LD are arranged relative to each other in the housing B to provide an LED effect. Likewise, the shape of the holes TFm and TNk depends on the shape of the diffusion elements LD. In the non-limiting example illustrated on the Figures 1 to 3 the diffusion elements LD and the holes TFm and TNk have substantially square shapes.

Each EO concealment element is installed between the housing B and the mask MA, behind the non-functional holes TNk. A blackout element E0 is arranged to prevent light from the (source) lamp S from passing through at least one non-functional hole TNk. We will understand that in the presence of a single occlusion element EO and several non-functional holes TNk (case of the nonlimiting example illustrated), this occulting element EO prevents the light that comes from the lamp (source) S to go through each of the non-functional TNk holes. It will also be understood that if the non-functional holes TNk are placed at different, non-adjacent locations with respect to the functional holes TFm, then several (at least two) EO occulting elements must be used if it is desired to prevent light which is from the lamp (source) S to go through the different non-functional holes TNk.

Furthermore, each EO occulting element may be colored or uncolored as required, and in particular depending on whether the area of the ice G which is located opposite the mask MA is colored or not colored. In general, it is advantageous that the obscuration element EO has a color which is substantially identical to that which presents the area of the ice G which is situated in front of the mask MA.

When the number N of diffusion elements LD is equal to the number M of functional holes TFm, each occlusion element EO can be installed next to the screen EC, behind one (or more, or all) holes (s). ) non-functional TNk. Preferably, the occulting element EO is pressed against the non-functional holes TNk in order to substitute for the non-planned diffusion elements LD because they are useless in the definition of the photometry of the function of the lamp plus mask system.

On the other hand, when the number N of diffusion elements LD is equal to the sum of the number M of functional holes TFm and of the number K of non-functional holes TNk, which is the case in the nonlimiting example illustrated on FIG. figure 2 each EO concealment element is preferably installed between the box B and the screen EC, behind one (or more or all) element (s) of diffusion LD which is (are) associated with (a) (or to, or non-functional, hole (s) TNk. With this type of placement of the blocking element EO, it is preferable that the latter (EO) directly surrounds as much as possible the LD diffusion elements behind which it is placed. It is for this reason that it is advantageous for the LD diffusion elements behind which it is placed to be surrounded by a minimum of material (as shown on the figure 2 ). Note that this may possibly require the presence of opening (s) and / or cut (s) in the occluding element EO for the passage of connecting bridges between the "functional" and "non-functional" diffusion elements LD. functional ".

It will be understood that the shape of an EO concealment element depends mainly on how the non-functional holes TNk and the associated diffusion elements LD are arranged relative to each other in the case B. In the nonlimiting example illustrated on the Figures 1 and 2 the non-functional holes TNk and the associated diffusion elements LD form substantially a square. As a result, the occulting element EO has a square or rectangular shape. But, it could have any other shape, including a triangular shape or L or U.

Thanks to the placements of the EO concealment element (possibly colored) proposed above, on the one hand, the non-functional holes TNk appear substantially of the same color as the functional holes TFm when the lamp plus mask system does not provide not its function (and therefore that the lamp S is off), thus allowing not to degrade the style, and secondly, the lamp plus mask system provides the desired photometry for its function (when the lamp S is lit).

The immobilization of an obscuration element EO with respect to the housing B, in its light concealment position, can for example be done by means of at least two pins (or pins) PT which are defined in places appropriate of the internal face FI of said housing B.

Each occlusion element EO may for example be made in the form of a substantially planar flexible seal. Such an EO seal may for example be made of synthetic rubber (such as EPDM ("Ethylene-Propylene Diene Monomer" - terpolymer of ethylene-propylene diene)). A substantially planar flexible seal can indeed relatively easily marry the shapes of the elements (or parts) between which (it) is placed, and thus prevent the passage of light through these elements (or parts).

The invention is not limited to the embodiments of optical block described above, only by way of example, but it encompasses all the variants that may be considered by those skilled in the art in the context of claims below.

Claims (9)

1. Motor vehicle headlight unit (FA) comprising i) a housing (B) accommodating at least a light source (S), a screen (EC) equipped with a number N of diffusion elements (LD) and placed in front of said light source (S), and a mask (MA) placed in front of said screen (EC) and equipped with M functional holes (TFm) respectively associated with at least some of said diffusion elements (LD) and K non-functional holes (TNk) placed beside said functional holes (TFm), and ii) a lens (G) placed in front of said mask (MA), characterised in that it further comprises at least an obscuring element (EO) installed between said housing (B) and said mask (MA) behind said non-functional holes (TNk) and arranged so as to prevent light emitted by said source (S) from passing through said non-functional holes (TNk).
2. Motor vehicle headlight unit (FA) comprising i) a housing (B) accommodating at least a light source (S), a screen (EC) equipped with a plurality of diffusion elements (LD) and placed in front of said light source (S), and a mask (MA) placed in front of said screen (EC) and equipped with a plurality of holes (TFm, TNk), at least some of which are respectively associated with at least some of said diffusion elements (LD), and ii) a lens (G) placed in front of said mask (MA), characterised in that it further comprises at least an obscuring element (EO) installed between said housing (B) and said mask (MA) behind only some of said holes (TNk) and arranged so as to prevent light emitted by said source (S) from passing through these obscured holes (TNk).
3. Headlight unit according to either claim 1 or claim 2, characterised in that the colour of said obscuring element (EO) is substantially identical to the colour of said lens (G) in front of the mask (MA).
4. Headlight unit according to any one of the preceding claims, characterised in that said obscuring element (EO) is a substantially planar flexible joint.
5. Headlight unit according to claim 4, characterised in that said joint (EO) is made of synthetic rubber.
6. Headlight unit according to any one of claims 1 to 5, characterised in that said number N of diffusion elements (LD) is equal to said number M of non-obscured holes (TFm), and in that said obscuring element (EO) is installed beside said screen (EC).
7. Headlight unit according to any one of claims 1 to 6, characterised in that said number N of diffusion elements (LD) is equal to the sum of the number M of non-obscured holes (TFm) and the number K of obscured holes (TNk), and in that said obscuring element (EO) is installed between said housing (B) and said screen (EC) behind the diffusion elements (LD) which are associated with the obscured holes (TNk).
8. Headlight unit according to any one of claims 1 to 7, characterised in that said housing (B) comprises, on an inner face (FI), at least two contact plates (PT) adapted to lock said obscuring element (EO) in the light-obscuring position thereof.
9. Headlight unit according to any one of claims 1 to 8, characterised in that said number M of non-obscured holes (TFm) is 6 and said number K of obscured holes (TNk) is 4.

Images