Windshield including a protective plate

Abstract

TITLE: Windshield comprising a protective plate. The present invention relates to a windshield (3) comprising a protective plate (9) arranged in a sensitive area of ​​said windshield, the sensitive area representing a surface area less than 5% of the total surface area of ​​said windshield (3), said protective plate being made of transparent ceramic or a transparent monocrystalline material having a Vickers hardness greater than 10 GPa. Abstract figure: Figure 2

Description

Title of the invention: Windshield comprising a protective plate Field of invention

[0001] The present invention relates to a windshield, comprising a protective plate intended to protect a sensitive area of ​​said windshield, in particular against scratches and / or impacts. The present invention also relates to a vehicle equipped with such a windshield. Prior art

[0002] Sapphire is the second hardest material on the Mohs scale, after diamond. This property makes it particularly interesting for creating anti-scratch films or anti-projectile armor.

[0003] For example, document WO 2006135832 describes an armor comprising sapphire. This armor is in particular intended to protect a military vehicle. This armor creates a shield, which makes it possible to prevent the penetration of projectiles.

[0004] Document WO2014078524 describes an electronic device, such as a mobile phone (or Smartphone), whose screen is equipped with a sapphire film. This film protects the screen against scratches and shocks.

[0005] Disadvantages of the prior art

[0006] A disadvantage of such films or armors is that sapphire is an expensive material, as it must be synthesized as a single crystal from a molten bath. The melting temperature is above 2000 °C, which makes the growth process very expensive.

[0007] Accordingly, at present, the use of such films or armors is limited to military applications or high-end products.

[0008] There is therefore a need for a protective device, which provides anti-scratch and / or anti-shock protection, and which has a reduced cost allowing it to be used on a wider range of products. Statement of the invention

[0009] These objectives, as well as others which will appear more clearly subsequently, are achieved using a windshield, comprising a protective plate, arranged at a sensitive zone of the windshield, the sensitive zone representing a surface area less than 5% of the total surface area of ​​the windshield, the protective plate being made of transparent ceramic or of a transparent monocrystalline material having a Vickers hardness greater than 10 GPa.

[0010] According to one embodiment of the invention, the protective plate is glued to the outer surface of the windshield, at the sensitive area.

[0011] According to another embodiment, the protection plate is inserted and glued into a recess machined in the windshield or into an opening cut in the windshield.

[0012] According to a particular embodiment of the preceding embodiment, the windshield is machined to create a recess in the thickness of the windshield, at the sensitive zone, the protective plate being inserted and glued into the recess.

[0013] According to another particular embodiment, the windshield is cut to create an opening in the windshield, at the sensitive area, the protective plate being inserted and glued into the opening.

[0014] According to another embodiment, the windshield is made of laminated glass. In this case, advantageously, the outer sheet of the windshield is cut at the sensitive area, the protective plate being inserted and glued into the cutout of the outer sheet. The inner sheet of the windshield can further be cut at the sensitive area, a second protective plate being inserted and glued into the cutout of the inner sheet.

[0015] The protective plate can be made of transparent ceramic based on aluminum oxynitride.

[0016] Alternatively, the protective plate may be made of a transparent monocrystalline material chosen from magnesium aluminate spinel, monocrystalline aluminum oxide, aluminum oxide or hydroxide, and zirconium silicate.

[0017] The invention also provides a vehicle, comprising: - a windshield as defined above, and - at least one data acquisition device arranged behind the windshield, said at least one data acquisition device being arranged to capture, through the windshield, data coming from outside the vehicle, the sensitive zone of said windshield being arranged in line with said at least one data acquisition device.

[0018] The vehicle may be an autonomous vehicle.

[0019] List of figures

[0020] The invention will be better understood on reading the following description of preferred embodiments, given as a simple figurative and non-limiting example, and accompanied by the figures among which: - [Fig.l] is a perspective view of a vehicle; - [Fig.2] is a partial cross-sectional view of a vehicle windshield of [Fig.l], according to a first embodiment of the invention; - [Fig.3] is a view similar to [Fig.2], the windshield being made of glass flaky; - [Fig.4] is a partial cross-sectional view of a vehicle windshield of [Fig.l], according to a second embodiment of the invention; - [Fig.5] is a view similar to [Fig.4], the windshield being made of laminated glass; - [Fig.6] is a partial cross-sectional view of a windshield of the vehicle of [Fig.l], according to a third embodiment of the invention; - [Fig.7] is a view similar to [Fig.6], the windshield being made of glass flaky; and - [Fig.8] is a partial cross-sectional view of a windshield of the vehicle of [Fig.l], according to a fourth embodiment of the invention. Detailed description of embodiments of the invention 1. Vehicle

[0021] [Fig.l] represents a vehicle 1. In the example, the vehicle 1 is a motor vehicle. In general, the invention can be applied to any type of vehicle, in particular a road vehicle (car, utility vehicle, truck, public transport: bus, coach, etc.) or rail vehicle (train, metro, tram, etc.). The invention can also be applied to an airplane or to an industrial or military vehicle.

[0022] The vehicle 1 comprises a passenger compartment 2, a front windshield 3, and a rear windshield 4, also called a rear window.

[0023] The vehicle 1 may be an autonomous, semi-autonomous or non-autonomous vehicle.

[0024] In the remainder of the description, the front windshield 3 is described in more detail. The rear windshield 4 of the vehicle 1 can be produced in a similar manner, and will therefore not be described in detail.

[0025] The windshield 3 can be made of laminated glass.

[0026] The term “laminated glass” refers to a glass comprising at least one external sheet 5 and one internal sheet 6, fixed together by a lamination interlayer 7.

[0027] The lamination interlayer 7 may for example be made of polymer, polyvinyl butyral (PVB), polyurethane (PU), plasticizer-free thermoplastic such as ethylene / vinyl acetate copolymer (EVA), or ionomer resin.

[0028] In a known manner, the windshield 3 can in this case be obtained by hot lamination of the different layers 5, 6, 7.

[0029] The windshield 3 may be curved. In the case of a motor vehicle, in the area of ​​the data acquisition device, the windshield generally has a horizontal radius of curvature greater than or equal to 0.9 m and a vertical radius of curvature greater than or equal to 0.5 m. These values ​​are given by way of example and depend on the application envisaged for the windshield.

[0030] The vehicle 1 further comprises a data acquisition device 8. In alternatively, the vehicle 1 may include several data acquisition devices.

[0031] The data acquisition device 8 is fixed, for example via a plate, behind the windshield 3, facing an area which is preferably located in the central and upper part of the windshield 3.

[0032] The data acquisition device 8 may be a sensor configured to detect the presence of at least one object in an external environment of the vehicle 1. The sensor is then configured to scan the external environment of the vehicle 1, for example by emitting radar waves.

[0033] The data acquisition device 8 may also be a camera, configured to capture images of the external environment of the vehicle 1. The camera may be a high-definition camera, called an HD camera, an infrared or near-infrared camera, or a thermal camera.

[0034] Generally speaking, the data acquisition device 8 here designates any device allowing the acquisition of data coming from outside the vehicle 1.

[0035] The use of several data acquisition devices 8, in particular the combination of at least one sensor and at least one camera, makes it possible to increase the level of security. 1. Protective plate

[0036] The windshield 3 comprises a protective plate 9. The thickness of the protective plate 9 is for example between 25 μm and 1 mm.

[0037] The protective plate 9 may have any shape, in particular circular, oval, ellipsoidal, rectangular, square or polygonal.

[0038] The protective plate 9 is arranged at a sensitive area of ​​the windshield 3. A sensitive area of ​​the windshield 3 is for example located at the right of the data acquisition device 8. Such an area is particularly sensitive to scratches, because any optical defect in the field of vision of the data acquisition device 8 can alter its operation. However, the reliability of the data acquisition device 8 is important, in particular in the case of a semi-autonomous or autonomous vehicle 1.

[0039] The surface area of ​​the sensitive zone depends on the size of the data acquisition device(s) 8, but remains small compared to the total surface area of ​​the windshield 3. The sensitive zone represents for example a surface area of ​​between 0.1% and 5% of the total surface area of ​​the windshield 3, preferably a surface area of ​​between 0.1% and 1% of the total surface area of ​​the windshield 3.

[0040] The protective plate 9 has a surface enabling it to cover the sensitive area. This surface is for example between 5 mm2 and 3000 mm2.

[0041] The sensitive area advantageously has a substantially flat surface. Indeed, a flat protective plate 9 is simpler and less expensive to produce, and the The curvature of the sensitive area must then be sufficiently low to allow bonding.

[0042] Generally speaking, the smaller the protective plate 9, the greater the curvature of the sensitive area can be without hindering bonding.

[0043] The maximum acceptable curvature Cmax of the sensitive zone can for example be defined as being equal to Cmax = 0.5 mm / a2, where a denotes the largest dimension of the protective plate 9. The corresponding minimum radius of curvature is then equal to 1 / Cmax. For a protective plate 9 whose largest dimension is equal to 10 mm, this gives a radius of curvature of 0.2 m, and for a protective plate 9 whose largest dimension is equal to 100 mm, this gives a radius of curvature of 20 mm.

[0044] The protective plate 9 can be made of transparent ceramic, for example transparent ceramic based on aluminum oxynitride (ALON).

[0045] The protective plate may alternatively be made of a transparent monocrystalline material having a Vickers hardness greater than 10 GPa.

[0046] A Vickers hardness measuring method is known per se and standardized, in particular by standard EN 6507. It will therefore not be described in detail here.

[0047] The result of the Vickers hardness measurement can be expressed in kilogram-force per square millimeter (kgf / mm2), also called the "HV number". The result of the Vickers hardness measurement can also be expressed in pascal. To convert the Vickers hardness number to pascal, the hardness number in kilogram-force per square millimeter (kgf / mm2) must be multiplied by the standard gravity (9.81), to obtain the hardness in MPa (N / mm2).

[0048] Such a transparent monocrystalline material may for example be chosen from magnesium aluminate spinel (Spinel), monocrystalline aluminum oxide (Sapphire), aluminum oxide or hydroxide (Alumina), or zirconium silicate (Zircon).

[0049] According to a first embodiment, shown in Figures 2 and 3, the protective plate 9 is glued to the outer surface of the windshield 3, at the sensitive zone.

[0050] According to a second embodiment, shown in Figures 4 and 5, the windshield 3 is machined to create a recess 10 in the thickness of the windshield 3, at the sensitive zone. The protective plate 9 is then inserted and glued into the recess 10.

[0051] The recess 10 is for example made with a milling cutter. Its depth is adapted so that the outer surface of the protective plate 9 is at the same level as the outer surface of the glass.

[0052] In the second embodiment, when the windshield 3 is made of glass laminated, the machining can be carried out by cutting the external sheet 5 of the windshield 3 at the level of said sensitive zone. The protective plate 9 is then inserted and glued into the recess 10 formed by the cutting of the external sheet 5. This cutting can be carried out before the assembly of the laminated glass, or after.

[0053] According to a third embodiment, shown in Figures 6 and 7, the windshield 3 is cut to create an opening 11 in the windshield 3, at the sensitive area. The protective plate 9 is then inserted and glued into said opening 11.

[0054] [Fig. 8] shows a fourth embodiment, in which the windshield 3 is made of laminated glass. Here, the outer sheet 5 of the windshield 3 is cut at the sensitive area. A first protective plate 9A is then inserted and glued into the cutout 10A of the outer sheet 5.

[0055] In addition, in the fourth embodiment, the inner sheet 6 of the windshield 3 is also cut at the sensitive area. A second protective plate 9B is then inserted and glued into the cutout 10B of the inner sheet 6.

[0056] In the various embodiments above, the bonding of the protective plate 9 may be carried out using a variety of mechanical or chemical means. Examples include heat-cured adhesives, radiation-cured adhesives, time-cured adhesives, chemically cured adhesives, and / or catalyst-cured adhesives, for example, polyurethanes, thermoplastic polyurethanes, epoxies, silicones, polyvinyl butyral, cyanoacrylate, and metal-based adhesives. Molten glass or other materials may also be used as the glue. One selection criterion is to optically match the glass and the protective plate 9, so as to minimize optical distortion.

[0057] The bonding can alternatively be carried out during the bending of the glass, while hot, without any addition of glue.

[0058] In the case of laminated glass, the lamination interlayer 7 can be used to bond the protective plate 9.

[0059] The windshield 3 may comprise several protective plates 9, to protect several sensitive areas.

[0060] Organic and / or inorganic coatings may be deposited on the glazing and / or on the protective plate(s) 9, to further increase the anti-scratch function.

[0061] The use of one or more protective plates 9 on targeted reduced areas thus makes it possible to effectively protect the windshield 3, 4, while limiting the impact on its price, therefore on the price of the vehicle 1.

[0062] Of course, the present invention is not limited to the embodiments described above as examples; it extends to other variants.

Claims

Claims

1. Windshield (3, 4), characterized in that it comprises a protective plate (9, 9A, 9B), arranged at a sensitive area of ​​said windshield, the sensitive area representing a surface area less than 5% of the total surface area of ​​said windshield (3, 4), said protective plate being made of transparent ceramic or of a transparent monocrystalline material having a Vickers hardness greater than 10 GPa.

2. Windshield according to claim 1, wherein said protective plate (9, 9A, 9B) is glued to the outer surface of the windshield (3, 4), at said sensitive area.

3. A windshield according to claim 1, wherein said protective plate (9, 9A, 9B) is inserted and bonded into a recess (10) machined in said windshield (3, 4) or into an opening (11) cut in said windshield (3, 4).

4. Windshield according to claim 3, wherein said windshield (3, 4) is machined to create a recess (10) in the thickness of said windshield, at said sensitive area, said protective plate (9) being inserted and glued in said recess.

5. A windshield according to claim 3, wherein said windshield (3, 4) is cut to create an opening (11) in said windshield, at said sensitive area, said protective plate (9) being inserted and glued into said opening.

6. Windshield according to any one of claims 1 to 5, wherein said windshield (3, 4) is made of laminated glass.

7. Windshield according to claim 6, wherein the outer sheet (5) of said windshield is cut at said sensitive area, said protective plate (9A) being inserted and glued into said cutout (10A) of the outer sheet.

8. Windshield according to claim 7, wherein the inner sheet (6) of said windshield (3, 4) is cut at said sensitive area, a second protective plate (9B) being inserted and glued into said cutout (10B) of the inner sheet.

9. Windshield according to any one of claims 1 to 8, wherein said protective plate (9, 9A, 9B) is made of transparent ceramic based on aluminum oxynitride.

10. A windshield according to any one of claims 1 to 8, wherein said protective plate (9, 9A, 9B) is made of a mo- transparent monocrystalline selected from magnesium aluminate spinel, monocrystalline aluminum oxide, aluminum oxide or hydroxide, and zirconium silicate.

11. Vehicle (1), in particular autonomous, characterized in that it comprises: - a windshield (3, 4) according to any one of claims 1 to 10, and - at least one data acquisition device (8) arranged behind said windshield, said at least one data acquisition device being arranged to capture, through the windshield, data coming from outside the vehicle, the sensitive area of ​​said windshield being arranged in line with said at least one data acquisition device.

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