FR3129194A1 - Emergency lighting device - Google Patents

Abstract

The invention relates to an emergency lighting device comprising a casing (10) having a signaling front face and a lower lighting edge equipped with lighting elements, said casing being adapted to be installed at height in buildings in order to be able to signal and illuminate predefined evacuation axes of said buildings located substantially in line with said box (10). Said lighting elements comprise a plurality of light-emitting diodes adapted to emit light rays, and said casing (10) comprises a plurality of parabolic lenses (50'', 52'', 54''), each of the parabolic lenses being adapted to be removably installed in line with a light-emitting diode in two positions opposite each other in order to be able to receive the light rays emitted and to re-emit light rays respectively in two distinct directions (F, F'). Figure to be published with abstract: Fig. 5

Description

Emergency lighting device

The present invention relates to an emergency lighting device intended to be installed in buildings to indicate emergency exits and to illuminate evacuation routes leading thereto.

One field of application envisaged is in particular that of guiding people in a building during an emergency evacuation, for example in the event of a fire or a power cut.

Known emergency lighting devices are commonly referred to as: luminaire or “ autonomous emergency lighting unit ”. The models, called beaconing, comprise a substantially rectangular parallelepiped box on the front face of which a safety or signaling pictogram is worn. Also, the device comprises a lighting member housed inside the case so as to be able to illuminate the pictogram to highlight it.

The case has a lower edge also equipped with lighting means. Thus, the box is installed, in buildings, at height and in particular above the doors so as to be able to mark out and illuminate, thanks to the lighting means mounted on the lower edge of the box, the evacuation routes.

Autonomous emergency lighting units also include a battery to ensure their operation and more precisely the lighting, when the building's power supply is cut.

In addition, the lighting power required varies according to the buildings and also according to the position in the buildings. Thus, the evacuation routes can be illuminated with a light intensity greater than 0.5 lux on the ground. Of course, the same box provides predetermined light fluxes, while the light intensity on the ground varies in particular according to its distance from the ground.

In addition, depending on the architecture of the buildings, it is necessary to install more or fewer boxes to be able to ensure sufficient marking and lighting.

Also, a problem which arises and which the present invention aims to solve is to provide lighting devices making it possible to reduce the number of boxes necessary and consequently to reduce installation costs.

For this purpose, there is proposed an emergency lighting device comprising a housing having a signaling front face and a lower lighting edge equipped with lighting members, said lighting members comprising a plurality of light-emitting diodes adapted to emit light rays, said box being adapted to be installed at a height in buildings in order to be able to signal and illuminate predefined evacuation axes of said buildings located substantially in line with said box. Said housing comprises on the one hand a plurality of biconvex lenses, each of the biconvex lenses being mounted respectively opposite the light-emitting diodes of said plurality of light-emitting diodes in order to be able to bend said light rays; and on the other hand a plurality of parabolic lenses, each of the parabolic lenses being adapted to be removably installed in line with a biconvex lens in at least two positions opposite each other in order to be able to receive the inflected light rays and to re-emit light rays respectively in at least two distinct directions.

Thus, a characteristic of the invention lies in the implementation of parabolic lenses to be able to focus the light rays coming from the light-emitting diodes and inflected by the biconvex lenses, in the directions that are desired. The parabolic lenses being adapted to be installed in a removable way, it is then easy to choose in situ, their orientation according to the need for lighting. It will be observed that the parabolic lenses make it possible to receive an incident light ray in a first direction and to re-emit it in a different direction inclined with respect to the first direction.

The biconvex lenses extend respectively between said light-emitting diodes and said parabolic lenses, and they thus receive the incident rays coming from the light-emitting diodes and they bend these incident rays to make them converge at the focal points of the lenses, opposite to the diodes. In this way, the light energy is concentrated at a point as will be explained below.

Also, thanks to the emergency lighting device according to the invention, it is then possible to reduce the number of boxes to be installed in the buildings and they can be integrated therein in a simpler way.

Also, and in a particularly advantageous manner, said housing defining a mean plane substantially parallel to said front face, one of said at least two distinct directions extends along a component perpendicular to said mean plane, while the other of said at least two distinct directions is substantially symmetrical with said one of said at least two directions with respect to said mean plane. In other words, the housing is adjusted so that the mean plane that it defines is substantially vertical and most generally, substantially perpendicular to the escape passage path. It is thus understood that the parabolic lenses make it possible to illuminate the evacuation passageway upstream of the box or downstream of the box corresponding to their possible installation in two opposite positions.

And of course, it is possible to orient a certain number of parabolic lenses towards the upstream of the case and another number, more important for example, towards the downstream, if one wishes to favor downstream lighting. The various adjustment possibilities of the parabolic lenses will be explained in more detail in the remainder of the description.

According to a particularly advantageous embodiment of the invention, said light-emitting diodes are mounted on a longitudinal plate installed on said lower lighting edge of said housing. The light-emitting diodes are for example installed step by step on a longitudinal printed circuit board and at a constant distance from each other. The longitudinal plate is then installed flush against the lower edge of the housing lighting.

Also, according to a preferred embodiment, said housing comprises a U-shaped longitudinal piece having a longitudinal bottom and two opposite longitudinal wings, said piece being adapted to straddle said light-emitting diodes, while said biconvex lenses are installed at through said longitudinal bottom. Thus, the U-shaped longitudinal part is applied against the lower edge so that the free edge of the two opposite longitudinal flanges bears against the lower edge on either side of the diodes. The U-shaped longitudinal piece is held in a fixed position against the lower edge, by snap-fastening means for example. In this way, the biconvex lenses are held in a fixed position facing each of the diodes.

Preferably, said biconvex lenses, said longitudinal bottom and said longitudinal wings are molded together in one piece in a polymer material. Advantageously, the polymer material is transparent, in order to be able to allow the passage of light through the parts of the bottom of the part forming the biconvex lenses. For example, the material is polymethyl methacrylate. Also, the plurality of biconvex lenses is produced and installed at a very advantageous cost.

Further, each of said parabolic lenses has a parabolic focal point, while each of said biconvex lenses has a biconvex focal point, and the parabolic focal points and the biconvex focal points coincide respectively. Thus, the light rays coming from the light-emitting diodes are respectively focused at the parabolic focal points of the parabolic lenses via the biconvex lenses. In this way, most of the light energy produced by the light-emitting diodes passes through the parabolic lenses. A large part of the light energy is then guided in a predetermined direction.

Also, said parabolic lenses are connected together at least in pairs on a mounting flange having at least two opposite legs. The parabolic lenses are for example joined in threes and they form a single piece with the fixing flange and the two opposite tabs. Thus, the three parabolic lenses are adapted to be adjusted facing three successive biconvex lenses.

According to a particularly advantageous embodiment of the invention, said fastening flange is adapted to be mounted by clipping astride said U-shaped longitudinal piece in two opposite positions. In this way, the fixing flange can be installed astride the U-shaped longitudinal part according to a first orientation so that the parabolic lenses coincide with the corresponding biconvex lenses, their foci being respectively coincident. But also, the fixing flange can be easily detached from the longitudinal part thanks to the elastic deformation of the legs, to be readjusted according to another orientation offset by 180° with respect to the first. According to this other orientation, the parabolic lenses also coincide with the corresponding biconvex lenses and their focal points are also respectively coincident.

It will be observed that the parabolic lenses are molded together in one piece with the fixing flange and the two opposite tabs. For example, the assembly is molded in one piece in a polymer material. The polymer material is for example polymethyl methacrylate.

Other particularities and advantages of the invention will become apparent on reading the description given below of particular embodiments of the invention, given by way of indication but not limitation, with reference to the appended drawings in which:
is a schematic three-quarter front perspective view of the emergency lighting device according to the invention;
is a schematic perspective view of an element of the invention;
is a schematic perspective view of another element of the invention;
is a schematic perspective view of yet another element of the invention;
is a schematic detail perspective view of the object of the ;
is a partial schematic view in profile section and according to the plane VII-VII of the object of the according to arrow VI; And,
is a partial schematic view in cross-section according to plan VII-VII illustrated on the .

There shows, in a right front three-quarter view, substantially from below, a housing 10 having a front face 12 opposite a rear face 14 and a lower edge 16 opposite an upper edge 18. The front face 12 has a pictogram 20 showing schematically a directional arrow and a character in motion.

Furthermore, the lower edge 16 is equipped with lighting elements 22 which will be described in detail.

First of all, the lighting elements 22 comprise a longitudinal printed circuit board 24, shown in detail in the . The longitudinal plate 24 has a length L and a width l . Also it has a first face 25 on which is implanted a plurality of light-emitting diodes 26, and a second opposite free face 27. The light-emitting diodes 26 are regularly spaced from each other by a pitch p .

The longitudinal plate 24 has, opposite the first face 25, a second face 28. And the longitudinal plate 24 is applied flat on the lower edge 16 of the housing 10 where it is held in a fixed position by fixing members. or by gluing. In addition, it is electrically connected through the lower edge 16 to power supply means not shown.

In addition, the longitudinal plate 24 is covered with a U-shaped longitudinal piece 30, as illustrated in the .

The U-shaped longitudinal piece 30 is molded in one piece in a transparent polymer material. It is for example molded in polymethyl methacrylate, more commonly referred to by its acronym PMMA. This polymer has the advantage of being transparent to visible light.

On the the longitudinal U-shaped piece 30 is shown upside down, and it has a longitudinal bottom 32, and two opposite longitudinal wings 34, 36 substantially diverging from each other from the bottom 32.

Also, the bottom 32 is molded so as to form a plurality of biconvex lenses 38. The biconvex lenses 38 each have a first optical axis x, x', x'', substantially perpendicular to the bottom 32. The first optical axes of the biconvex lenses 38 are substantially parallel to each other. Only two biconvex lenses 38 are referenced on the , and only three first optical axes x, x′, x″ are shown for reasons of clarity of the drawing.

In addition, the biconvex lenses 38 are spaced from each other so that the optical axes of two contiguous lenses are spaced apart by a pitch p′ identical to the spacing pitch p of the light-emitting diodes 26.

In addition, the two opposite longitudinal flanges 34, 36 are spaced apart from each other by a distance greater than the width l of the longitudinal plate 24 represented on the .

The U-shaped longitudinal piece 30 has two opposite ends 40, 42, one from the other by a distance substantially greater than the length L of the longitudinal plate 24. And the two opposite longitudinal flanges 34, 36 are connected between they at each of its ends 40, 42.

In addition, the opposite longitudinal flanges 34, 36 define two opposite free edges and they have pairs of notches 44, 46; 44', 46' at these free edges. Also, the notches 44, 46 are respectively located in line with two bottom portions 32 themselves located on either side of a biconvex lens 38.

In addition, a transverse rib 48 extends projecting from the opposite longitudinal flanges 34, 36, above each of the notches 44, 46; 44', 46'.

It will also be observed that the pairs of notches 44, 46; 44', 46' are spaced apart a distance equivalent to the spacing of three biconvex lenses 38.

We will now refer to the showing a first parabolic assembly of the invention 49, including three parabolic lenses 50, 52 and 54 mounted on a mounting flange 56. The first assembly 49 of the three parabolic lenses 50, 52 and 54 and mounting flange 56 is molded in one piece in a polymer material allowing the passage of light, and for example, in polymethyl methacrylate.

The set shown in the has a longitudinal base 58 on which are erected and aligned the parabolic lenses 50, 52 and 54 in the form of scales.

Each of the parabolic lenses 50, 52 and 54 has a convex surface 60 opposite a concave surface 62. The convex surfaces 60 of the three parabolic lenses 50, 52 and 54 are oriented in the same direction, while the concave surfaces 62 are oriented in an opposite direction.

Also, the parabolic lenses 50, 52 and 54 have focal points not shown on this and located respectively in the thickness of the lenses. Furthermore, it will be observed that the focal points are spaced from each other by a pitch p′ equal to the pitch p′ of spacing of the second optical axes of the biconvex lenses 38 illustrated on the .

Further, the first set 49 includes two pairs of opposing legs 64, 66; 68, 70 extending from the longitudinal base 58 opposite the parabolic lenses 50, 52 and 54. The opposite legs 64, 66; 68, 70 of the two pairs of legs are respectively curved towards each other and end in facing hooks 72; 74.

Also, the opposite legs 64, 66; 68, 70 of the two pairs of legs are symmetrical to each other with respect to a median plane Pm perpendicularly intersecting the longitudinal base 58 and extending between the convex 60 and concave 62 surfaces of the parabolic lenses 50, 52, 54.

It will be observed that the two pairs of opposite legs 64, 66; 68, 70 are spaced apart by a distance corresponding to the distance between the notches 44, 46; 44', 46', distance corresponding to that which separates two parabolic lenses 50, 52 and 54.

Thus, the lighting elements 22 illustrated in the fitted to the lower edge 16 of the casing 10, comprise: the longitudinal plate 24, the second free face 27 applied flat against the lower edge 16, the longitudinal U-shaped part 30 covering the longitudinal plate 24, the two opposite longitudinal flanges 34 , 36 bears against the lower edge 16 on each side of the longitudinal plate 24 and so that the biconvex lenses 38 come respectively opposite the light-emitting diodes 26, and a plurality of assemblies 49 as illustrated in the and coming astride the U-shaped longitudinal piece 30 as will be explained below in more detail.

Exactly there shows in detail, according to a particular mode of implementation, lighting units 22', according to which, a first assembly 49 has been installed astride the U-shaped longitudinal part 30 facing three first biconvex lenses 38, while the following three biconvex lenses 38 are left free. The first assembly 49 is held in a fixed position on the longitudinal profiled part in view 30 thanks to the two pairs of opposite legs 64, 66; 68, 70 including the facing hooks 72; 74 respectively come into engagement inside the notches 44, 46; 44', 46', behind cross ribs 48.

The first assembly 49 is thus clipped onto the longitudinal U-shaped part 30. During clipping, that is to say the force driving of the assembly 49 against the longitudinal U-shaped part 30, the opposite tabs 64, 66 ; 68, 70 of each of the pairs respectively deviate from each other by elastically deforming to resume their close position when the facing hooks 72, 74 extend respectively facing the notches 44, 46; 44', 46'. The first assembly 49 is thus removably installed on the longitudinal U-shaped piece 30 because it can be easily removed by force.

The following six biconvex lenses 38 are covered with a second set 49' and a third set 49'', totally identical to the first, and installed astride the U-shaped longitudinal piece 30, in the same way as the first together 49.

It will be observed that the first 49 and third set 49'' are oriented in one direction, while the second set 49' is oriented in an opposite direction. In other words, the convex surfaces 60 of the parabolic lenses of the first and third sets 49, 49'' are oriented towards the front of the , while the convex surface 60 of the parabolic lenses of the second set 49' is oriented towards the rear of the .

We will now refer to the showing more in detail in profile section and according to the arrow VI marked on the , the third set 49'' installed astride the longitudinal piece profiled in 30.

We find on the , the longitudinal plate 24 bears against the lower edge 16 and on which is located a light-emitting diode 26. There is also the longitudinal U-shaped part 30, the two opposite longitudinal wings 34, 36 of which bear against the lower edge 16 Also, a biconvex lens 38 extends opposite the light-emitting diode 26.

In addition, the third assembly 49'' is held in a fixed position on the longitudinal U-shaped part 30 thanks to the fixing flange 56'', so that the parabolic lenses 50'', 52'' and 54'' come respectively extend in line with a light-emitting diode 26 and facing a biconvex lens 38.

Thus, the facing hooks 72'', 74'' of the opposite legs 64'', 66'';68'',70'' extend into notches 44, 46; 44', 46' and behind the transverse ribs 48 so as to maintain the assembly 49'' in a fixed position. Note that only the 72'' hook appears on the engaged inside the notch 44', the other elements being hidden.

Also, the 62'' concave surface of the 50'', 52'' and 54'' parabolic lenses appear in front of the while the 60'' convex surfaces appear backwards.

Thanks to the 56'' fixing flange whose opposite legs 64'', 66'';68'',70'' are elastically deformable, it is easy to unclip the first set 49'' and to orient it in a direction offset by 180° to reclip it, so that the concave surface 62''50'',52'' and 54'' parabolic lenses appear behind the and that the convex surfaces 60'' appear forward.

On the , the cutting plane of the housing 10, is produced along the optical axes of the biconvex lens 38 and of the parabolic lens 54", which are coplanar. It is of course the same for the other biconvex lenses and the other parabolic lenses respectively .

Also, reference will now be made to the showing in section the parabolic lens 54'' and the associated biconvex lens 38 to explain its role thanks to the light-emitting diode 26.

We find on the , in cross section, the longitudinal U-shaped part 30 and its two opposite longitudinal wings 34, 36 apply to the lower edge 16 of the housing 10. In addition, there are also the two opposite tabs 64'', 66'' in taken respectively in the two opposite wings 36,34.

The parabolic lens 54'' is then held opposite the biconvex lens 38 which itself extends opposite the light-emitting diode 26 supported by the longitudinal plate 24.

Also, the biconvex lens 38 has a first focus 76, or biconvex focus, while the parabolic lens 54'' has a second focus 78, or parabolic focus, coinciding with the first focus 76.

In this way, the light energy produced by the light emitting diode 26 is focused through the biconvex lens 38 at the second focal point 78 of the parabolic lens 54''. The light rays intersecting the second focal point 78 are reflected against the convex surface 60'', in the thickness of the parabolic lens 54'' to be redirected in the optical direction F through the concave surface 62''.

The optical direction F of the parabolic lens 54'' is inclined with respect to the optical axis x of the biconvex lens 38, by an angle less than 90° for example. Also, the optical axis of the biconvex lens 38 is oriented substantially vertically. Consequently, the light energy produced by the light-emitting diode 26 is focused by the biconvex lens 38. The light rays are guided by the parabolic lens 54" and are reflected on the convex surface 60" to be redirected according to parallel rays in the optical direction F.

Consequently, the light is projected substantially towards the rear of the case 10, in the direction F, in the dihedral angle formed by the vertical and horizontal planes crossing at the level of the parabolic lens 54".

We find on the the convex surfaces 60'' of the three parabolic lenses 50'', 52'' and 54'' of the third set 49'' emitting light projected towards the rear of the case 10 in the direction F'.

Also, it is understood that the second set 49', oriented opposite the third set 49'' tends to emit light opposite, towards the front of the case 10, in a second direction F.

Furthermore, the following three biconvex lenses 38 are free and therefore they transmit the light emitted by the light-emitting diodes 26 in a main vertical direction.

As for the first set 49, its three parabolic lenses 50, 52 and 54 tend to emit light in the same direction F' as the parabolic lenses 50'', 52'' and 54'' of the third set 49''.

Thus, the three sets 49, 49' and 49'' being removable, it is understood that they can be adjusted to transmit the light towards the front of the case 10 or even towards the rear or else be removed so that the light is emitted in a vertical direction directly by the biconvex lenses 38.

Claims (8)

Emergency lighting device comprising a housing (10) having a signaling front face (12) and a lower lighting edge equipped with lighting members (22), said lighting members (22) comprising a plurality light-emitting diodes (26) adapted to emit light rays, said box being adapted to be installed at a height in buildings in order to be able to signal and illuminate predefined evacuation axes of said buildings located substantially in line with said box (10);
characterized in that said housing (10) comprises:
- a plurality of biconvex lenses (38), each of the biconvex lenses being mounted respectively facing light-emitting diodes (26) of said plurality of light-emitting diodes (26) in order to be able to bend said light rays; And,
- a plurality of parabolic lenses (50, 52, 54), each of the parabolic lenses being adapted to be removably installed in line with a biconvex lens (38) in at least two positions opposite each other to to be able to receive the inflected light rays and to re-emit light rays respectively in at least two distinct directions (F, F'). Lighting device according to claim 1, characterized in that, said casing (10) defining a mean plane substantially parallel to said front face (12), one of said at least two distinct directions extends along a component perpendicular to said mean plane, while the other of said at least two distinct directions is substantially symmetrical with said one of said at least two directions with respect to said mean plane. Lighting device according to claim 1 or 2, characterized in that said light-emitting diodes (26) are mounted on a longitudinal plate (24) installed on said lower lighting edge (16) of said casing (10). Lighting device according to any one of Claims 1 to 3, characterized in that the said casing (10) comprises a U-shaped longitudinal piece (30) and having a longitudinal bottom (32) and two opposite longitudinal wings (34, 36), said piece being adapted to straddle said light-emitting diodes (26), while said biconvex lenses (38) are installed through said longitudinal bottom (32). Lighting device according to claim 4, characterized in that said biconvex lenses (38), said longitudinal bottom (32) and said longitudinal wings (34, 36) are molded together in one piece in a polymeric material. Lighting device according to any one of claims 1 to 5, characterized in that each of said parabolic lenses (50, 52, 54) has a parabolic focus (78), while each of said biconvex lenses (38) has a biconvex (76), and in that the parabolic foci and the biconvex foci respectively coincide. Lighting device according to any one of Claims 1 to 6, characterized in that the said parabolic lenses (50, 52, 54) are connected together at least in pairs on a fixing flange (56) having at least two opposite (64, 66; 68, 70). Lighting device according to claim 4 and 7, characterized in that said fixing flange (56) is adapted to be mounted by clipping straddling said U-shaped longitudinal piece (30) in two opposite positions.