Light box with volume diffuser

Abstract

A light box (2) for a cabin (4) of a vehicle (6) comprises a frame (8) surrounding a cavity (10), at least one light source (14) arranged on a first side (12a) of the cavity (10), and a light surface (18) arranged on a second side (12b) of the cavity (10) for emitting light (16) generated by the light source (14), which extends along a surface (20). In a transverse direction (22) perpendicular to the surface (20), at least one diffuser (24) for the light (16) is arranged in the cavity (10) between the light source (14) and the light surface (18). The diffuser is a volume diffuser extending parallel to the surface (20) and is not a solid. A cabin (4) of a vehicle (6) contains the light box (2). A vehicle (6) contains either the light box (2) or the cabin (4).

Description

The invention relates to a light box, having a light source and a light surface which serves to emit the light generated by the light source into the environment, and having a diffuser for the light which is arranged between the light source and the light surface and serves to harmonise the light distribution on the light surface.EP 0 795 468 A2 discloses a lighting system in passenger cabins, in particular for passenger aircraft. A light box uses not a point light source but a rod-shaped light source. A light-transmissive housing forms the light box. Individual extractors arranged side by side, the tips of which point toward the light source, in conjunction with the rod-shaped light source, make possible uniform illumination of the entire light box. An application of such a light box as a ceiling lighting part is illustrated. Other possible applications would be the illumination of advertising panels or side cladding parts.The object of the present invention is to propose improvements in relation to a light box.The object is achieved by a light box according to claim 1. preferred or advantageous embodiments of the invention and other categories of invention are evident from the further claims, the following description and the attached figures.The light box is one for a cabin of a vehicle, i.e. is provided for proper use therein. "Proper" means that the light box is structurally matched to a specific or a specific type of cabin / vehicle and is designed for use there; e.g. for the geometry / material and system requirements determined thereby, etc. In other words, a cabin / aircraft in question is in particular assumed to be known with regard to its geometry, size, material properties etc. The cabin is in particular a passenger cabin. The vehicle, in particular a vehicle for passenger transport, in particular an aircraft, in particular a passenger aircraft; however, it can also be a railway or a bus.The light box includes a frame, the frame surrounding a cavity. The cavity has two opposite sides, is in particular cuboidal and has in particular flat sides. At least one light source is arranged on a first side of the cavity. The light source is configured to emit light into the cavity or through the cavity toward the light surface during operation. A light surface is arranged on a second side of the cavity, which is opposite the first side. The light source and the light surface are parts of the light box. The light surface serves or is configured to emit light into the environment of the light box, wherein this light is generated or is generated by the light source. The cavity is itself empty or filled with ambient air.The light surface extends along an extension surface. The extension surface is in particular a plane, above all if the light surface is also planar. The light surface is therefore also planar in particular.Viewed in a transverse direction transversely to the area of extent, at least one, in particular a plurality, for example two to four, in particular three, scattering bodies is arranged between the light source and the light surface. These are in particular the same. The diffuser is configured to diffuse the light on the path from the light source to the light surface. The scattering is configured-in conjunction with the light source-in such a way that the spatial distribution of the light on the light surface is harmonized. The light surface should therefore appear luminous homogeneously / with homogeneous brightness distribution.The scattering body is a volume scattering body which extends parallel to the extension surface. The volume scattering body is not a solid solid body. The latter means that the volume scattering body is neither a classic solid-material film, solid-material pane, solid-material coating / paint system of a pane or another solid material. "solid body" does not mean, however, that it is a rigid body. The volume scattering body can be flexible / bendable. The term is to be understood here merely in the sense of solid / dense / without cavities. It is therefore not a conventional plastic or glass pane, paint coating or film, for example.The scattering body extends in particular over the entire surface of the light box or the entire surface of the light surface.Because the volume scattering body is not a solid solid body, it in turn has gaps, cavities, air spaces, etc. enclosed therein and becomes lighter as a result, but nevertheless fulfills its task of sufficiently scattering the light on the path from the light source to the light surface.In a preferred embodiment, at least one, in particular a plurality or all, of the scattering bodies is a nonwoven. The fleece extends in particular in a leaf-like manner parallel to the extension surface. The nonwoven material has the corresponding cavities and therefore forms a particularly advantageous volume scattering body.In a preferred embodiment, the scattering body is a mineral scattering body, in particular based on glass, in particular made of mineral, in particular glass, fiber material. This has particularly good scattering properties for light and is still fire-resistant for this purpose, which is of great advantage above all when used in aviation.In a preferred embodiment, at least two, in particular two or three scattering bodies are arranged cascaded one after the other, in particular parallel to one another, as seen in the transverse direction. In other words, a plurality of scattering bodies are located one behind the other between the light source and the light surface and thus in the light path. Depending on the number of scattering bodies, therefore, this results in at least double or multistage / cascaded light scattering, which leads to particularly effective harmonisation of the light emerging from the light source at the light surface.In a preferred variant of this embodiment, at least two of the scattering bodies are layered one above the other in a manner lying against one another in the transverse direction. In other words, an overall scattering arrangement is formed from a lamination of individual individual scattering bodies lying against one another. In particular, the scattering bodies bear directly against one another, that is to say are layered directly one above the other without the interposition of other elements (for example connecting means such as adhesive). In particular, they loosely abut each other. The totality of the layered scattering bodies as an overall scattering arrangement can be easily handled in the light box or can be introduced or fastened into the latter.In a preferred variant of these embodiments, at least two of the scattering bodies adjacent in the transverse direction are not fastened to one another, in particular are not glued to one another, and at most lie loosely on one another / on one another. Thus, the scattering bodies can be introduced into the light box in a particularly simple manner and do not need to be processed accordingly beforehand in order to attach them to one another, for example in order to glue them to one another.Alternatively, however, the at least two of the scattering bodies adjacent to one another in the transverse direction can be fastened to one another, in particular glued to one another. The scattering bodies, in particular nonwovens, are then, for example, bonded and placed together in the light box. It is a concern that scattering bodies which are not fastened to one another could shift relative to one another and, for example, folds could arise in a nonwoven. The concerns could be unauthorized if the scattering bodies / nonwovens are circumferentially gripped / fixed at their edges. In other words, a structure can thus be created which provides adhesive (adhesive web) for connection between the scattering bodies / nonwovens.An adhesive woven fabric is particularly suitable. "Adhesive woven fabric" is a loose web of adhesive threads, comparable to a network of fine threads, which in particular also resembles a spider web ("woven").In a preferred embodiment, the light surface is a mechanically stable / rigid / rigid pane (as above: in the technical sense). In particular, it is a glass / plastic, polycarbonate (PC) or acrylic glass pane (PMMA: polymethyl methacrylate). In aviation, only special polycarbonate (PC) is permitted because of stability and fire requirements to be fulfilled; in particular, this is therefore a corresponding pane. The light box thus has a mechanically stable front side / light outlet side.In a preferred embodiment, at least one of the scattering bodies is fixed, e.g. glued, on the side facing the cavity on or on the light surface, in particular disc. This produces a composite of pane and scattering body which is particularly easy to handle. In particular, a full-surface bonding takes place.In a preferred embodiment or variant alternative to full-surface fixing, at least one of the scattering bodies is fastened only on the edge side (i.e. on its edge) or linearly or at points, e.g. on the frame and / or on the light surface or the pane. In its remaining regions, the scattering body is not fastened and, if need be, rests loosely on a counter-point, for example the light surface. This simplifies the production of the corresponding light box.In a preferred variant of this embodiment, the scattering body is placed loosely on the light surface, in particular the pane, in addition to the fastening (in all non-fastened regions).For all the variants mentioned, it is also possible for a plurality of scattering bodies to be layered one above the other in a joint without being bonded, fastened together, etc.In a preferred embodiment, the frame is a box closed except for the light surface. In particular, the light surface then completes the box completely, i.e. the cavity is then completely tightly enclosed. On the light surface, a design or grid structure or braces is optionally present, which can optionally be part of the light box / frame. Such can also serve to support the light surface / pane. In other words, this results in a light box in which, in particular, light emission through the frame with the exception of the light surface is prevented. The box or cavity can also be designed to be dust- and dirt-proof.The object of the invention is also achieved by a cabin according to claim 12 of a vehicle. The cabin contains the light box according to the invention. The cabin and at least a part of its possible embodiments and the respective advantages have already been explained accordingly in connection with the light box according to the invention.The object of the invention is also achieved by a vehicle according to claim 13.In particular, the cabin is a passenger cabin.The vehicle and at least a part of its possible embodiments and the respective advantages have already been explained accordingly in connection with the light box according to the invention and the cabin according to the invention.In particular, the vehicle is an aircraft, in particular a passenger aircraft.The invention is based on the following findings, observations or considerations and still has the following preferred embodiments. These embodiments are also sometimes referred to simply as "the invention". The embodiments can also contain parts or combinations of the above-mentioned embodiments or correspond to these and / or optionally also include embodiments not mentioned up to now.The invention is based on the finding that ceiling panels backlit in the entrance area of passenger aircraft are used as "Welcome Area". These are backlit by a light box. Normally, this is done with indirect light. However, this has the disadvantage of being too dark (outside the specification) due to high light loss. Alternatively, it could be attempted to apply more light to the panel by direct lighting and diffuser of the film(s). The disadvantage here is that the LED light sources are seen through the panel and diffuser film. A diffuser film is thus insufficient. If two or more are used, the light intensity is again attenuated too much.The following solutions would be conceivable here:• Use of a light box with indirect illumination.• Use of ice lacquer on the rear side of the panel pane as diffuser.• Alternatively, an inserted diffuser foil behind the pane.• Light box with diffuser plate / film and disc.• Directly a milky disc.The use of a diffuser foil is to be considered as critical, since these could not meet the fire requirements. Further measures for fire protection would then have to be taken.The basic idea of the invention, on the other hand, is the scattering of the light not in a plane but in a volume body. The solid body is not a coloured solid body, but rather a glass fleece. This results in a high scattering effect at an extremely low density. As a result, the light losses are significantly lower than in a solid body.The basic idea is also the use of glass fiber material of lower density as bulk scattering bodies; with high fiber spacings for long paths between the individual breaking points, which greatly reduces the losses. The idea is a light mineral material as scattering body that does not burn.The basic idea is furthermore: A plurality of layers of nonwoven are also placed over the pane as required in an existing construction of a light box with direct illumination. The number of layers can thus be minimized for the application and thus also the light losses. The fastening can be fastened over the full surface by adhesive bonding or on the edge by various connecting measures, for example clamps or screws.According to the invention, the following result:• Better Scattering• Lower Light Losses• Adjustable Thickness / Thickness as Required• Meeting Fire Requirements• Light weight• Few material sets• cost-effectiveAccording to the invention, light-volume diffuser light box systems in aviation are particularly obtained.According to the invention, in particular homogenization of the (emerging) light from the light box structure results. In addition, a visual protection for direct LED illumination in the light box (light source). The diffuser (diffuser) meets the severe fire requirements, especially heat release, in the aircraft or (railroad) cabin.Further features, effects and advantages of the invention will become apparent from the following description of a preferred exemplary embodiment of the invention and from the attached figures. In each case, a schematic schematic diagram shows: FIG. 1 shows a light box in broken-out perspective sketch view obliquely from below, FIG. 2 shows an alternative light box in a mounted state in a cabin of a vehicle in an oblique view, FIG. 3 is a cross-sectional view of a portion of the light box of FIG. 2, FIG. 4 shows the light box from FIG. 2 with the cover removed, and FIG. 5 shows an oblique view after inserting a scattering body.FIG. 1 shows a light box 2 for mounting in a cabin 4 of a vehicle 6 (see FIG. 2 ). The light box 2 contains a frame 8 (only symbolically indicated here) which is rectangular in shape and which surrounds a hollow space 10 which is also rectangular in shape. The cavity 10 has a first side 12 a, shown at the top in FIG. 1, and opposite a second side 12 b, here accordingly at the bottom.Since FIG. 1 shows a view obliquely from below of the light box 2, the first (upper) side 12 ais concealed and therefore indicated only by dashed lines. Arranged on the first side 12 aof the cavity 10 (within the frame 8) is a light source 14 which emits light 16 during operation, indicated by an arrow in FIG. 1.On the second side 12 bof the cavity 10, the light box 2 has a light surface 18, here a glass pane. The light surface 18 serves for emitting the light 16 which was generated by the light source 14 and has passed through the cavity 10 or the light surface 18. The light 16 is emitted into the surroundings of the light box 2 and thus into the cabin 4 here. The light surface 18 extends along an extension surface 20, here a plane, since the light surface 18 is likewise embodied in a planar manner.In FIG. 1, the extension surface 20 is drawn in such a way that it coincides with the light surface 18.Viewed in a transverse direction 22 perpendicular to the extension surface 20, a scattering body 24 is arranged in the cavity 10 between the light source 14 and the light surface 18. The diffuser 24 scatters the light 16 on its path from the light source 14 to the light surface 18, as indicated by arrows in FIG. 1, so that a uniform light distribution of the light 16 is ultimately present on the light surface 18. The light 16 is perceived by a viewer in the cabin 4 as if the light surface 18 were a light source that evenly radiates homogeneously over the entire surface.The scattering body 24 is here a volume scattering body which extends parallel to the extension surface 20 and which is not a solid solid body. In the present case, the scattering body 24 is a mineral scattering body which extends in a leaf-like manner parallel to the extension surface 20, in this case a nonwoven 26 in the form of a glass nonwoven made of glass fiber material. The scattering body 24 is indicated in the figure by a hatched area.In the present case, a second scattering body 24 is also arranged parallel to the first scattering body 24, only indicated by a second dashed line in FIG. 1. The two scattering bodies 24 are layered one above the other in a manner lying against one another in the transverse direction 22, in the process they lie directly against one another, but are not fastened to one another but lie loosely on one another.In other words, the two scattering bodies 24 lie loosely on top of one another and are not glued to one another.The light surface 18 is here a mechanically stable pane, namely a glass pane. The scattering bodies 24 are fastened here only on the edge side, i.e. on their circumferential edge 28, here on the frame 8.FIG. 2 shows a detail from a vehicle 6, here a passenger aircraft, namely from its cabin 4 in the form of a passenger cabin. An alternative light box 2 is mounted here in a ceiling 30 of the cabin 4. In the mounted state M shown, only the light surface 18 and a region of the frame 8 adjacent to the latter can be seen, the remaining frame 8 or light box 2 is countersunk in the ceiling 30. The frame 8 is also continued here in the region of the light surface 18, here in the manner of a design structure, in the form of a grid, in order to improve the optical appearance of the light box 2.The cabin 4 according to FIG. 2 therefore contains the light box 2. the vehicle 6 therefore contains the cabin 4 with the light box 2.FIG. 3 shows a cross section through a part of the light box 2 from FIG. 2 ; in contrast to FIG. 1, the scattering body 24 lies loosely on the light surface 18 in the form of a glass pane.FIG. 4 shows the light box 2 from FIGS. 2 and 3 before the diffuser 24 is introduced, wherein a cover 32 of the light box 2 which can be released for maintenance purposes is raised. The cavity 10 is thus still empty here. Therefore, as shown in FIG. 4, the view of the light surface 18 in the form of the glass pane is free. The design structure of the frame 8 can again be seen through the glass pane.It can also be seen here that the frame 8 (including closed cover 30) here is a box which is closed apart from the light surface 18 and which, in the closed state, keeps dust and dirt away from the cavity 10. The light surface 18 or pane then completely seals the box or cavity 10.FIG. 5 shows the light box 2 from FIG. 4 after the scattering body 24 has been introduced into the cavity 10 in the form of a single fleece 26 and has been loosely deposited here on the light surface 18. By means of a clamping device 34, not explained in more detail, the scattering body 24 is subsequently clamped firmly only on the two left and right side edges in the figure, i.e. only on the edge side, here linear, and is thus fixed in the light box 2 in a sufficiently secure manner.List of reference characters2 Light box 4 Cabin 6 Vehicle 8 Frame 10 Cavity 12 a, bFirst, second side 14 Light source 16 Light 18 Light surface 20 Extension surface 22 Transverse direction 24 Diffuser 26 Nonwoven fabric 28 Edge (diffuser) 30 Ceiling 32 Cover 34 Clamping device M Mounted stateReferences included in the specificationThis list of documents cited by the applicant has been produced in an automated manner and is only included for the better information of the reader. The list is not part of the German patent application or utility model application. The DPMA does not take any adhesion for any faults or omissions.Patent Literature citedEP 0 795 468 A2

[0002]

Claims

Light box (2) for a cabin (4) of a vehicle (6), - with a frame (8) surrounding a cavity (10), - with at least one light source (14) arranged on a first side (12a) of the cavity (10), - with a light surface (18) arranged on a second side (12b) of the cavity (10) for emitting light (16) generated by the light source (14), which extends along an extension surface (20), - wherein at least one scattering body (24) for the light (16), which scattering body is a volume scattering body extending parallel to the extension surface (20) and is not a solid solid body, is arranged in the cavity (10) between the light source (14) and the light surface (18) as viewed in a transverse direction (22) transversely to the extension surface (20).Light box (2) according to claim 1, characterised in that at least one of the scattering bodies (24) is a non-woven.Light box (2) according to any one of the preceding claims, characterized in that the diffuser (24) is a mineral diffuser (24) made of mineral material.Light box (2) according to one of the preceding claims, characterized in that, as seen in the transverse direction (22), at least two scattering bodies (24) are arranged one after the other in cascaded fashion.Light box (2) according to Claim 4, characterized in that at least two of the scattering bodies (24) are layered one above the other in a manner lying against one another in the transverse direction (22).Light box (2) according to one of Claims 4 to 5, characterized in that at least two of the scattering bodies (24) which are adjacent in the transverse direction (22) are not fastened to one another and at most loosely bear against one another.Light box (2) according to one of the preceding claims, characterized in that the light surface (18) is a mechanically stable pane.Light box (2) according to one of the preceding claims, characterized in that at least one of the scattering bodies (24) is fixed on the light surface (18) on the side facing the cavity (10).Light box (2) according to one of the preceding claims, characterized in that at least one of the scattering bodies (24) is fastened only on the edge side or in a linear or punctiform manner.Light box (2) according to Claim 9, characterized in that the scattering body (24) is otherwise placed loosely on the light surface (18).Light box (2) according to one of the preceding claims, characterized in that the frame (8) is a box which is closed apart from the light surface (18).Cabin (4) of a vehicle (6), comprising the light box (2) according to one of the preceding claims.Vehicle (6), with the light box (2) according to one of claims 1 to 11 or with the cabin (4) according to claim 12.

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