The invention relates to a vehicle glazing, which is suitable in particular for illuminating an interior of a motor vehicle.
An interior light for a means of transportation is known from document DE 10360729 B4, in which an interior light is integrated with a printed circuit board having light-emitting diodes and electronics in a composite glass pane.
One object to be achieved is to specify an improved concept for glazings, which is more flexible to handle and enables a simplified production sequence.
This object is achieved with the subject matter of the independent patent claim. Refinements and embodiments are the subject matter of the dependent claims.
The improved concept is based on the idea of providing individual components of a vehicle glazing with illumination function separately, and subsequently combining them to form a composite using conventional production methods. In this case, in particular a component which is responsible for the light emission is prepared separately and can then be combined with a conventional pane, which can also be used in vehicle glazings without illumination function. Accordingly, a light source is also provided separately and can be attached without additional steps to the arrangement, which also enables simple replaceability of the light source, for example, for maintenance purposes. By way of the improved concept, production costs and also storage costs of the individual components of the overall arrangement can be reduced.
In one embodiment of the improved concept, a vehicle glazing comprises a pane, which e.g. is formed from toughened glass, TG in short, a light-conducting layer, and a light source. The light-conducting layer is configured to conduct light coupled in at one of its end sides and has decoupling means, via which a light exit of conducted light is caused on at least one of its main surfaces. The light-conducting layer is materially bonded to the pane. The light source is arranged such that light is coupled in on at least one end side of the light-conducting layer. Furthermore, a refractive layer is arranged between the pane and the light-conducting layer, which has a lower index of refraction than the light-conducting layer. The refractive layer is simultaneously implemented as a lamination layer.
Planar emission of light, which is coupled laterally into the layer, is enabled by way of the light-conducting layer having the decoupling means. Due to the refractive layer, for example, light which is guided in the light-conducting layer does not reach the refractive layer, but rather is reflected back into the light-conducting layer. This causes, inter alia, a higher light yield and better light transport in the light-conducting layer. In addition, the refractive layer prevents light from being radiated through the pane, i.e. light from the vehicle interior reaching the outside, for example. The pane itself can be a conventional pane, which is not affected by the light guiding or light emission. A uniform optical impression can be achieved by the material bond. The production outlay is further reduced by the simultaneous embodiment of the refractive layer as the lamination layer.
In one embodiment, the material bond is formed by means of the lamination layer. For example, a polyvinyl butyral film, PVB film in short, is used for this purpose.
The surface fraction of the layer in which the decoupling means are provided can be varied from a small fraction up to a complete surface embodiment depending on the application.
The arrangement of the light source outside the composite of pane and light-conducting layer enables a complex lamination of an illumination unit into a composite glass pane to be omitted. In addition, the necessity is dispensed with of conducting required electrical energy for an illumination unit into the composite glass pane, since in a vehicle glazing according to the improved concept, light coupling is performed directly or via corresponding optical waveguides into the light-conducting layer.
Due to the special arrangement of the light source on the edge of the composite or the light-conducting layer, the light source, which is formed from LEDs, for example, is also subjected to less thermal stress than when it is laminated into the glass composite. In addition, the light source can be replaced easily, so that destruction of the composite between pane and light-conducting layer does not occur.
In various embodiments, a holding element can optionally be provided on the composite, which enables fastening on a vehicle body of the vehicle. Additionally or alternatively, an optional foam embedding of the edge region of the composite made of pane and light-conducting layer can be provided, which can also enclose the light source.
In some embodiments of the vehicle glazing, the light-conducting layer extends over the entire surface of the pane, so that the pane and the light-conducting layer form a glass composite or a composite glass, respectively. In a minor alteration thereof, it is also possible that the light-conducting layer extends over the entire surface of the pane with the exception of an edge region of the pane. A glass composite is also formed between pane and light-conducting layer in this embodiment.
In alternative embodiments, the light-conducting layer is attached in one or more partial regions of the surface of the pane. For example, the light-conducting layer has a strip shape or a ring shape and preferably extends on one or more edges of the pane. Decoupling of the light from the light-conducting layer is performed in this case, for example, both perpendicularly to the main surface of the pane or the light-conducting layer and also at the edge facing away from the light source or the end side of the light-conducting layer facing away from the light source. A desired light mood can thus be achieved in particular.
In various embodiments, the light-conducting layer is formed from glass, in particular a TG or a heat-strengthened glass, HSG in short.
Alternatively, the light-conducting layer is formed from a transparent plastic, in particular from polymethyl methacrylate, PMMA in short, or from a polycarbonate, PC in short. In particular in such an embodiment of the light-conducting layer from plastic, the decoupling means are formed, for example, by light-scattering particles embedded in plastic. The light-scattering particles are preferably not visible to the naked eye and cause a transparent impression of the plastic layer when the light source is turned off. The embedded particles cause scattering of the light at the particles, so that it is incident at an angle on the surface of the light-conducting layer, which enables an exit.
In other embodiments, both for embodiments of the light-conducting layer using glass and also using plastic, the decoupling means are formed by structuring of a surface of the light-conducting layer. The structuring is preferably embodied on the entire surface of the light-conducting layer. Alternatively, a desired illumination image can be generated by only regional structuring. Furthermore, the main surface of the light-conducting layer, which faces toward the pane, is preferably structured. The structuring of the surface can be performed, for example, by mechanical structuring, for example, impression of structures, by printing, in particular using a pad print, by etching, or by a blasting method, for example, sandblasting.
The light-conducting layer is implemented in various embodiments as a rigid plate, both in the embodiments using plastic and also using glass.
In one embodiment of the light-conducting layer using plastic, in particular using polycarbonate, the light-conducting layer can also be implemented as flexible, in particular as a flexible film. Such a flexible film may be fastened or laminated onto the pane with low production technology expenditure.
In the above-mentioned embodiments, a scratch-resistant coating can be applied in each case to the main surface of the light-conducting layer facing away from the pane.
The various described embodiments of the vehicle glazing enable modular applicability. In particular, the light-conducting layer can be combined with existing panes or roof glazings, without substantial design changes being necessary. The light-conducting layer can be constructed so that it has no or only a slight influence on force-transmitting elements of the vehicle glazing.
The invention will be explained in greater detail hereafter on multiple exemplary embodiments on the basis of the figures. Elements which have equivalent function or action bear the same reference signs in this case. Insofar as individual elements are described for one of the figures, the description thereof in the following figures is not necessarily repeated.
In the figures:
The decoupling is based on the effect that light is refracted or scattered on the structuring 13 and is therefore emitted at an angle which enables an exit from the surface of the layer 12. Without the structuring, the coupled-in light is typically incident at such a flat angle on the surface of the layer 12 that total reflection of the light occurs.
The structuring 13 of the surface of the layer 12 is produced mechanically, for example, by imprinting the structure into the surface, for example. Alternatively, the structuring can be caused by printing, in particular using a pad print, so that the printed material represents the scattering structures. A further possibility for the structuring of the surface of the layer 12 consists of etching of the surface, by which the surface is roughened to generate the scattering effect. Furthermore, the roughening or structuring can also be achieved by a blasting method, for example, by sandblasting.
In this embodiment, a holding element 18 is provided in the edge region of the vehicle glazing 3, which is used, for example, as a fastening element of the glazing on the body or the roof 2 of the vehicle 1. A part of the holding element 18 is provided with a foam embedding 20, for example, which is embodied, for example, using a polyurethane (PU) foam. The light source 16 is enclosed by the holding element 18 in this embodiment, and therefore protected from external influences.
The bonding layer 14 can have multiple functions. On the one hand, it can be used as a lamination layer, which causes a permanent bond between the pane 10 and the layer 12. In addition, the layer 14 can be implemented as a refractive layer, which in particular has a lower index of refraction than the light-conducting layer. Light incident on the interface between the layer 12 and the layer 14 thus remains in the light-conducting layer 12 and does not pass into the pane 10. Light absorption in the pane 10 or light exit from the vehicle into the surroundings is avoided in this way.
Additionally, the layer 14 can exercise the function of a splinter protection layer or splinter protection film. For example, the layer 14 is implemented for this purpose from polyvinyl butyral, PVB in short.
The layer 14 is preferably provided so that it acts both as a lamination layer and also as a refractive layer, and furthermore simultaneously as a splinter protection film. Alternatively, the three functions can also be caused by a corresponding layer structure of multiple films.
In the embodiment of the light-conducting layer 12 in
The layer 22 is implemented, for example, as an oblong strip or as a ring extending all around the pane 10. Therefore, surface illumination is not produced in this embodiment, but rather only illumination at the edge of the pane 10. Light decoupling from the layer 22, which is illustrated by corresponding arrows, is performed by the corresponding decoupling means both essentially perpendicular to the surface of the pane 10 or the layer 22 and also at an end side of the layer 22 opposite to the light source 16.
In all above-described embodiments of the vehicle glazing 3, a scratch-resistant coating can be applied below the light-conducting layer, i.e. on the side of the light-conducting layer facing away from the pane 10. Furthermore, in the illustrated embodiments of the vehicle glazing 3, the light source 16 is attached directly to the light-conducting layer in each case. Notwithstanding this, the light source can also be provided at another position and light conduction at the end face of the light-conducting layer can be supplied via corresponding optical waveguides.
Alterations and combinations of the described embodiments are, of course, possible and included by the invention.
Number | Date | Country | Kind |
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10 2012 109 900.6 | Oct 2012 | DE | national |
Filing Document | Filing Date | Country | Kind |
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PCT/EP2013/071521 | 10/15/2013 | WO | 00 |