Glass assembly for an illuminated vehicle roof, manufacturing process for a glass assembly, and illuminated vehicle roof

Abstract

A glass assembly for an illuminated vehicle roof (30, 50) comprises a glass plate (38), a glass backing layer (40), and a polyurethane layer (42). The glass plate (38) has the glass backing layer (40) on one side, while a polyurethane layer (42) is applied over the glass backing layer (40). An illuminated vehicle roof (30, 50) and a method for manufacturing a glass assembly (34) are further described. Figure 2

Description

Title of the invention: Glass assembly for an illuminated vehicle roof, method of manufacturing a glass assembly, and illuminated vehicle roof

[0001] The invention relates to a glass assembly for an illuminated vehicle roof, to a method of manufacturing a glass assembly, and to an illuminated vehicle roof.

[0002] The requirements for vehicle roofs have changed considerably in recent years. An improved cabin ambience is increasingly demanded by the market, with a significant step towards improving the cabin ambience having been achieved through the introduction of illuminated glass roofs.

[0003] These illuminated glass roofs are often made in the form of sunroofs and comprise a laminated glass plate in the form of a semi-finished product for the manufacture of the illuminated glass roof. A common embodiment of such a laminated glass plate is a laminated safety glass having the arrangement order glass plate / plastic film / glass plate.

[0004] Illuminated glass roofs comprising a single glass plate instead of the laminated glass plate are also known, which are provided with a layer, for example a polyurethane layer. This allows a simpler and more compact structure in comparison with laminated safety glass.

[0005] Illuminated glass roofs further comprise a frame in which are arranged luminous elements which illuminate the glass plate of the laminated safety glass facing the vehicle interior or the polyurethane layer attached to the individual glass plate.

[0006] Known illuminated glass roofs comprising an individual glass plate and a polyurethane layer fixed thereto, however, have the disadvantage that the polyurethane layer adheres poorly to the glass plate and that the polyurethane layer detaches from the glass plate during the manufacture of the vehicle roof or during operation of the vehicle. Vibrations introduced during operation of the vehicle further promote this negative effect.

[0007] The present invention therefore aims to provide an illuminated vehicle roof which is lightweight compared to the state of the art, and which at the same time has a very long lifespan.

[0008] According to the invention, the object is achieved by a glass assembly for an illuminated vehicle roof, comprising a glass plate, a glass base layer and a polyurethane layer. The glass plate is provided, on one side, with the layer of glass bottom, the polyurethane layer being applied on this glass bottom layer.

[0009] The mentioned structure of the glass assembly is therefore very light, since only one glass plate is installed. The thickness of the glass assembly is further only slightly increased by the polyurethane, which is relatively light and can be made thin. The glass primer layer also serves as an adhesive between the glass plate and the polyurethane layer.

[0010] The glass base layer is characterized in particular in that the wetting properties and adhesion to the glass plate are improved, which simplifies manufacturing and enables reliable bonding.

[0011] According to one aspect of the invention, the glass bottom layer has a lower light refractive index than the adjacent polyurethane layer. Due to the light refractive index of the glass bottom layer being lower than the light refractive index of the adjacent polyurethane layer, it is possible to guide the light introduced from the side efficiently into and along the polyurethane layer.

[0012] The glass base layer is advantageously provided, at at least one local location, with a diffusion structure which is designed to diffuse incident light. The advantage here is the targeted guidance of the light to the outside. It is possible to apply to the vehicle roof any shape predefined by the manufacturer or any pattern having several shapes, capable of being made visible by illumination of the vehicle roof.

[0013] According to one embodiment, the glass plate is a tempered glass, in particular a tempered safety glass. This increases the breakage resistance of the glass assembly and provides better protection for the vehicle passengers. It is further possible to reduce scrap during manufacturing by using a tempered safety glass.

[0014] According to one aspect of the invention, the glass plate is a tinted glass, in particular a gray glass or a green glass. The choice of a correspondingly tinted glass plate also makes it possible to positively influence the ambience of the passenger compartment. For example, less sunlight penetrates into the interior of the vehicle thanks to this measure. The vehicle passengers can also be protected from prying eyes from outside the vehicle.

[0015] Another advantage is that an illuminated diffusion structure on the vehicle roof is also visible in daylight since the contrast of the illuminated diffusion structure relative to its immediate surroundings increases.

[0016] Another aspect of the invention provides that the polyurethane layer is transparent. A transparent polyurethane layer promotes light guidance since less light is absorbed. The illuminated vehicle roof therefore shines brighter.

[0017] The transparent polyurethane layer further simplifies the manufacturing process of the glass assembly. For example, it is possible to use glass plates with different tinting intensities for the manufacturing of glass assemblies with different tinting intensities. Thus, the sunlight penetrating from the vehicle environment is reduced only by the possibly tinted glass plate.

[0018] The polyurethane layer is advantageously made in such a way that ultraviolet and infrared rays incident on the polyurethane layer are not transmitted. Vehicle passengers who are sensitive to UV rays are thus even better protected against ultraviolet sunlight than in the case of ordinary glass. Protection against infrared rays from the sun striking the vehicle is also achieved. The vehicle interior therefore heats up less.

[0019] According to another embodiment, the polyurethane layer is provided, at at least one local location, with a diffusion structure which is designed to diffuse incident light. As in the case of a diffusion structure on the glass base layer, targeted guidance of the light to the outside can also be achieved by means of a diffusion structure in the polyurethane layer, the guidance of light to the outside being here also capable of being carried out on a predefined shape or any pattern having several shapes. The diffusion structure in the polyurethane layer is in particular an incorporated laser engraving.

[0020] The invention further relates to an illuminated vehicle roof comprising a glass assembly according to the invention as described above and a frame surrounding the glass assembly, on which at least one light element is mounted, the light element being arranged on an end face of the glass assembly in such a way that the light from the light element is able to be coupled planarly into the polyurethane layer. The coupled light can be guided through the polyurethane layer which serves as a light guide. This is particularly effective since the light is reflected several times on the boundary surfaces of the polyurethane layer and is thus deflected in the direction of the diffusion structure. The brightness of the illuminated diffusion structure is thus increased.

[0021] The frame advantageously comprises an opaque polyurethane material in the area of ​​the mounted light element. Thanks to this embodiment, the light is guided exclusively in the polyurethane layer. The light element is thus noticed in a less annoying manner by a passenger of the vehicle since light cannot enter the vehicle interior through the frame. In other words, this measure provides a further improvement in the ambience of the vehicle interior.

[0022] According to one embodiment, conductive tracks are incorporated in the frame, and said at least one light element is designed as a light unit, the light unit comprising a printed circuit board having plug-in contacts and a light-emitting diode (LED) mounted on the printed circuit board. The light unit is further clipped into the frame, and the plug-in contacts are electrically connected to the conductive tracks. The light element is thus designed modularly as a light unit, so that it can be very easily replaced. Interchangeability is thus ensured, so that in the event of a technical defect, it is not necessary to replace the entire illuminated vehicle roof.

[0023] The object is further achieved by a method of manufacturing a glass assembly, in particular of manufacturing a glass assembly as described above for an illuminated vehicle roof, the method comprising the following steps:

[0024] - supply of a glass plate;

[0025] - application, in particular automated application of a glass base layer on a first surface of the glass plate; and

[0026] - application of a layer of polyurethane on the glass base layer.

[0027] The method described promotes the connection of the polyurethane to the glass plate by that better adhesion is achieved between the glass plate and the polyurethane layer due to the applied glass primer layer.

[0028] The automated application of the glass primer further prevents streaking and unevenness during the application of the glass primer, thereby improving the aesthetics of the illuminated glass roof.

[0029] One aspect of the invention provides that the glass plate, before the application of the glass base layer, is cleaned at least on its first side, in particular thermally or by means of an adhesive cleaner. This provides the advantage that the glass base layer adheres better to the glass plate, whereby the polyurethane layer is ultimately also more reliably connected to the glass plate by the glass base layer.

[0030] According to one embodiment of the method, a diffusion structure that diffuses incident light is incorporated into the polyurethane layer by laser in a further step. The laser is an inexpensive means for incorporating a diffusion structure, as additional materials are then not required. The laser also allows a high production rate in production, which in turn results in reduced costs.

[0031] The invention is explained in the following with the aid of various exemplary embodiments described by means of the accompanying drawings. These show:

[0032] [Fig-1] a laminated safety glass according to the state of the art in section transverse;

[0033] [Fig.2] an illuminated vehicle roof according to the invention in an embodiment in cross section;

[0034] [Fig.3] an illuminated vehicle roof according to the invention in another embodiment realization in a top view;

[0035] [Fig.4] a luminous element of the illuminated vehicle roof according to [Fig.3] in a top view, the light element being produced in the form of a light unit; and

[0036] [Fig.5] a detail of the illuminated vehicle roof according to [Fig.3].

[0037] Illuminated vehicle roofs are part of the state of the art and are intended to improve the ambience of the interior of a vehicle. By illuminating a predefined pattern incorporated during manufacture in the vehicle roof, the latter is made visible. Known diffusion structures are, for example, applied to the illuminated vehicle roof in the form of a ceramic print pattern.

[0038] It is thus possible, thanks to the known technique, to simulate a starry sky by illuminating a vehicle roof provided, for example, with a pattern of stars, and thus to improve the ambiance of the vehicle interior.

[0039] The already known illuminated vehicle roofs most often comprise several integrated light elements which illuminate the pattern predefined by the manufacturer and produced in the form of a diffusion structure in the vehicle roof, the light emitted by the light elements which strikes the diffusion structure being diffused into the vehicle interior.

[0040] Standard semi-finished products such as laminated safety glass with partially tempered glazing are known from the state of the art for the manufacture of illuminated vehicle roofs.

[0041] It should be noted that illuminated vehicle roofs made of glass are part of the so-called overhead glazing. Overhead glazing must provide high safety for car passengers to protect passengers in the event of an accident and not bring them into an even more dangerous situation, for example due to flying shards.

[0042] When using partially tempered glass in laminated safety glasses, large coherent fragments which still have a high residual load capacity are produced in the event of breakage, for example following a car accident. In particular, laminated safety glasses do not break completely, because they are held together by an elastic composite material.

[0043] [Fig.l] shows an exemplary structure of such a laminated safety glass 10 according to the state of the art, which is used as standard in many illuminated vehicle roofs.

[0044] The laminated safety glass 10 of an illuminated glass roof is composed of an upper glass plate 12 facing away from the passenger compartment of the vehicle, a lower glass plate 14 facing towards the passenger compartment of the vehicle, and an intermediate plastic film 16, the plastic film 16 being the elastic composite material described above. The two outer glass plates 12, 14 are connected to each other by cooperation of materials by means of a laminating process by subjecting them to pressure and heat.

[0045] In the illuminated vehicle roofs of the state of the art, the plastic film 16 fulfills two functions. On the one hand, for the safety of the passengers, it has a high breaking strength and viscoplastic properties, and on the other hand, it ensures that the light introduced by the light elements is retained inside the lower glass plate 14 of the laminated safety glass 10 by several reflections. The lower glass plate 14 thus acts as a kind of light guide.

[0046] Light reflected several times at the boundary surfaces of the lower glass plate 14 is introduced laterally into the laminated safety glass 10 of the vehicle roof. [Fig. 1] shows for this purpose next to the laminated safety glass 10 a light element 18, here a light-emitting diode (LED), and a reflected ray path 20 of a light ray drawn in an exemplary manner.

[0047] Two boundary surfaces 22, 24 are responsible for the reflection in the lower glass plate 14. One is between the lower glass plate 14 and the plastic film 16, and the second is between the lower glass plate 14 and the passenger compartment of the vehicle which, as is known, is filled with air.

[0048] The plastic film 16 and the air-filled vehicle interior have a lower light refractive index than the adjacent lower glass plate 14, whereby the light ray is at least partially reflected.

[0049] [Fig. 2] shows a structure of a vehicle roof 30 according to the invention. The vehicle roof 30 comprises a plurality of light elements 32, a glass assembly 34 according to the invention, and a frame 36 surrounding the glass assembly 34.

[0050] The light elements 32 serve to introduce light into the vehicle roof, the light elements 32 being arranged for this purpose distributed on the front faces of the glass assembly 34.

[0051] By means of the light elements 32 arranged laterally on the front face of the glass assembly 34, their emitted light is introduced in a flat manner into the glass assembly 34. In the following, the light is efficiently guided towards a diffusion structure 37 located in the glass assembly 34, which diffuses the light rays introduced into the passenger compartment of the vehicle.

[0052] The glass assembly 34 according to the invention comprises a glass plate 38, here a tempered safety glass, a glass base layer 40, for example a Chemlok-144 layer, and a transparent polyurethane layer 42 (PU / PUR layer). The glass base layer 40 is arranged in a flat manner on one side of the glass plate 38 and adheres to it. The polyurethane layer 42 is for its part integral with the glass base layer 40.

[0053] Thanks to the described structure of the glass assembly 34, the required mounting space on the vehicle is reduced compared to a laminated safety glass 10, since a second glass plate is not necessary. The glass base layer 40 further enables a reliable adhesive connection between the polyurethane layer 42 and the glass plate 38.

[0054] The light introduced in a planar manner and introduced into the glass assembly 34 as previously described is more precisely introduced into the polyurethane layer 42 of the glass assembly 34 and is then guided towards the diffusion structure 37.

[0055] In the present embodiment, the diffusion structure 37 is incorporated into the polyurethane layer 42 of the glass assembly 34. However, it is also possible, as an alternative or in addition, to apply, in particular to print, a diffusion structure 37 on the base layer 40.

[0056] In addition to the function of an adhesive agent, the adjacent glass bottom layer 40 fulfills another function. Thus, the material of the glass bottom layer has been chosen such that its light refractive index is lower than the light refractive index of the adjacent polyurethane layer. In the case of introducing light into a polyurethane layer directly adjacent to the glass plate 38, light could escape into the glass plate 38 without being reflected on the boundary surface.

[0057] In contrast to the known state of the art according to [Fig. 1], the light is introduced and transmitted in a planar manner in the polyurethane layer 42 and not in the lower glass plate 14. By analogy, the multiple reflections as described above at the boundary surfaces 22, 24 of the lower glass plate 14 occur only at the boundary surfaces of the polyurethane layer 42.

[0058] In the present embodiment, the glass plate 38 of the glass assembly 34 according to the invention is a gray glass which has a light refractive index of approximately 1.52. The transparent polyurethane layer 42 also has a light refractive index of approximately 1.52, and the base layer of glass 40 has a lower light refractive index than the adjacent polyurethane layer 42.

[0059] Due to these specified light refractive indices and the structure of the glass assembly 34 as previously described, it appears that light can be deflected in a manner similar to the known structure of the prior art according to [Fig.l].

[0060] The polyurethane layer 42 of the glass assembly 34 serves primarily to guide light in the glass assembly 34. It can also serve to protect the vehicle passengers against ultraviolet and infrared radiation from the sun.

[0061] For this purpose, the polyurethane layer 42 is specifically designed to at least partially isolate ultraviolet and infrared radiation. Thus, the vehicle interior heats up less, and sun-sensitive passengers can be better protected against harmful ultraviolet radiation. This can, for example, be achieved by adding additives to the starting material of the polyurethane layer 42, for example a viscous polyurethane starting material.

[0062] In order to be able to offer good protection to the passengers of a vehicle having a vehicle roof according to the invention in the event of an accident, it is possible, in the present embodiment, to use toughened safety glass as the glass plate 38.

[0063] The frame 36 of the illuminated vehicle roof 30 is made of black polyurethane. Its function is to hold the illuminated vehicle roof 30 together as a unit. For this purpose, it receives the light elements 32 and the glass assembly 34.

[0064] The frame 36 is further provided with conductive tracks which guide electrical energy towards the light elements 32. The conductive tracks are for their part connected to a source of electrical energy.

[0065] During manufacture, the frame 36 may be manufactured by foaming around the glass assembly 34, the conductive tracks and the light elements 32 being simultaneously foamed into the frame 36.

[0066] The light elements 32 are embedded in the frame 36 in such a way that the light from the light elements 32 can be coupled planarly into the polyurethane layer 42. At the same time, the light from the light elements 32 does not radiate through the frame 36, since the black polyurethane of the frame 36 is opaque. An isolated light introduction is thus achieved.

[0067] The further embodiment of a vehicle roof 50 according to the invention shown in Figures 3 and 5 differs from the previously described embodiment in that the light elements 32 are designed as light units 52 and are mounted on the frame 54 in a particular manner.

[0068] These light units 52 each comprise a printed circuit board 56 having plug-in contacts 58 and a light-emitting diode (LED) 60 mounted on the printed circuit board 56, as shown in [Fig.4].

[0069] A possible positioning of the light units 52 in the frame 54 is shown in [Fig. 3] solely as an example, the light units 52 being arranged in the corners of the rectangularly designed vehicle roof 50.

[0070] As already described above for the embodiment according to [Fig. 2], the frame 54 of the embodiment according to [Fig. 3] is also provided with conductive tracks, the plug-in contacts 58 of the light units 52 being electrically connected to the conductive tracks in the mounted state. In contrast to the embodiment according to [Fig. 2], only the conductive tracks are foamed into the frame 54, but not the light units 52.

[0071] The corresponding method according to the invention for the manufacture of a glass assembly 34 is explained in the following with the aid of [Fig. 2].

[0072] For the manufacture of a glass assembly 34, the glass plate 38 is first provided with the desired shape and size.

[0073] At least one first face of the glass plate 38 is then cleaned using an adhesive cleaner to remove any dirt, in particular oil films which would considerably reduce the adhesion of the glass base layer 40 to the glass plate 38. The adhesive cleaners used for this purpose are most often liquids containing solvents, for example based on alcohol or acetone. This process is also called adhesion activation, the adhesive cleaner also being called an adhesion activator.

[0074] Alternatively, thermal cleaning of the glass plate 38, for example by a flame, is also possible.

[0075] A glass base layer 40 is then applied automatically to the first face of this glass plate 38, ensuring in particular that the glass base layer 40 is applied uniformly and that there is no formation of streaks which would have a negative influence on the optical appearance of the glass assembly 34.

[0076] The polyurethane layer 42 is then applied uniformly and flat on the glass base layer 40.

[0077] After the subsequent curing of the polyurethane layer 42 applied in viscous form, the finished glass assembly 34 is ready.

[0078] The diffusion structure 37 can then be applied by laser to the polyurethane layer 42 of this glass assembly 34. The diffusion structure 37 is then a kind of laser engraving. The application or incorporation of the diffusion structure diffusion 37 by another technique, for example a ceramic printing process, is however also conceivable.

Claims

Claims

1. Glass assembly for an illuminated vehicle roof (30, 50), having a glass plate (38), a glass base layer (40) and a polyurethane layer (42), the glass plate (38) being provided on one side with the glass base layer (40), and the polyurethane layer (42) being applied to this glass base layer (40), wherein the glass base layer (40) is provided, at at least one local location, with a diffusion structure (37) made to diffuse incident light or wherein the polyurethane layer (42) is provided, at at least one local location, with a diffusion structure (37) made to diffuse incident light.

2. Glass assembly according to claim 1, characterized in that the glass base layer (40) has a light refractive index which is lower than that of the adjacent polyurethane layer (42).

3. Glass assembly according to one of the preceding claims, characterized in that the glass plate (38) is a tempered glass, in particular a tempered safety glass.

4. Glass assembly according to one of the preceding claims, characterized in that the glass plate (38) is a tinted glass, in particular a gray glass or a green glass.

5. Glass assembly according to one of the preceding claims, characterized in that the polyurethane layer (42) is transparent.

6. Glass assembly according to one of the preceding claims, characterized in that the polyurethane layer (42) is made in such a way that ultraviolet and infrared rays incident on the polyurethane layer (42) are not transmitted.

7. An illuminated vehicle roof comprising a glass assembly (34) according to one of the preceding claims and a frame (36, 54) surrounding the glass assembly (34), on which at least one light element (32) is mounted, the light element (32) being arranged on an end face of the glass assembly (34) such that light from the light element (32) is able to be coupled planarly into the polyurethane layer (42), wherein the frame (36) comprises an opaque polyurethane material in the area of ​​the mounted light element (32).

8. Illuminated vehicle roof according to claim 7, characterized in that conductive tracks are incorporated in the frame (54) and said at least one light element (32) is designed as a light unit (52), the light unit (52) comprising a printed circuit board (56) having plug-in contacts (58) and a light-emitting diode (LED) mounted on the printed circuit board (56), and the light unit (52) being clipped into the frame (54) and the plug-in contacts (58) being electrically connected to the conductive tracks.

9. A method of manufacturing a glass assembly for an illuminated vehicle roof, in particular according to one of claims 1 to 6, the method comprising the following steps: - providing a glass plate (38); - applying, in particular automated applying, a glass base layer (40) to a first surface of the glass plate (38); and - applying a polyurethane layer (42) to the glass base layer (40), the method comprising a further step in which a scattering structure (37) which scatters incident light is incorporated into the polyurethane layer (42) by laser.

10. Method according to claim 9, characterized in that the method comprises an additional step in which the glass plate (38), before the application of the glass base layer (40), is cleaned at least on its first face, in particular thermally or by means of an adhesive cleaner.

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