FR3088035A1 - VEHICLE GLAZING WITH INTEGRATED ELECTRONIC DEVICES AND AN INTEGRATED COOLING SYSTEM - Google Patents

Abstract

A glazing (301) for a motor vehicle with an integrated cooling device is disclosed. The glazing, of the laminated glazing type, integrates electronic devices which are encapsulated in interlayer sheets of PVB which form the core of the glazing. The integration of a cooling system (302), also encapsulated in the PVB sheets, makes it possible to cool these devices when the temperature of the glazing exceeds a determined threshold and reaches values liable to damage them if they are kept in operation .

Description

DESCRIPTION

TITLE: Motor vehicle glazing with integrated electronic devices and an incorporated cooling system

Technical area

The present invention relates generally to the field of motor vehicle glazing, and more particularly glazing incorporating electronic devices.

It relates to such a motor vehicle glazing with a system for cooling the integrated electronic devices, as well as a motor vehicle incorporating it.

State of the art

Materials science and electronics technology now make it possible to design motor vehicle glazing that is intelligent glazing. These are glazings which allow, thanks to the integration of electronic devices at the heart of the glazing itself, to perform specific functions which can be triggered by external factors and / or by manual commands from a user who is at on board the vehicle.

The assembly of a stack of layers of materials with various properties to form the glazing and the integration of electronic devices on certain layers of this stack, offers possibilities for very wide functionality. The glazing concerned is in particular roof glazing or windshields, because these are so-called laminated glazings in the sense that they consist of a stack (that is to say a superposition) of glass sheets and sheets of polymeric material. This assembly is carried out in the first place to give the glazing properties of flexibility and particular security, the shards of glass remaining glued to the polymer sheets in the event of an impact causing the glazing to break). But it also has the advantage of allowing easy integration of electronic devices by the conventional techniques of depositing semiconductor materials on glass substrate and their insulation by the polymer layers. The electronic devices are then encapsulated in the glazing, being protected from the outside environment.

This allows for example to offer glazing whose optical properties can be changed in response to a command from a user. For example, some motor vehicle roof glazing today allows its user to switch the glazing from a transparent state to a translucent state, and vice versa. Active control of the optical properties of the glazing is obtained by means of an active diffusive film which is integrated into the glazing, in its thickness, and which can be made transparent or translucent on command by subjecting it or not to a determined electrical voltage . When the film is transparent, the light rays pass through the glazing in a way that makes it possible to clearly distinguish an object behind the glazing. Conversely, when the film is translucent, the light rays pass through the glazing in a way which does not allow, due to a diffusive effect, to distinguish an object located behind the glazing. The advantage of such a device is to offer the users of a motor vehicle the possibility of benefiting both from optimum brightness inside the passenger compartment and of limiting, where appropriate, the exposure passengers at the sight of others or in direct sunlight.

This also allows, in another example, to integrate light sources directly into the glazing. For example, certain roof glazings incorporate in their thickness such sources which fulfill the function of reading light and which can be activated or deactivated by a touch control which is also integrated into the glazing. The interest in this case is both aesthetic and linked to the gain in space achieved through this integration.

In most cases, an electronic device integrated into a car window glass which performs a certain function (we then speak of a functional electronic device) is associated with an electronic module which makes it possible to control its operation (we then speak of an electronic control device) . Such an electronic module makes it possible for example to adapt a supply voltage, to generate a control signal or any other function necessary for the operation of the associated functional electronic device. In most cases, this electronic module is itself also integrated into the glazing. This is why, in the context of the present description, such a module is included among the integrated electronic devices to which reference is made.

The operation of electronic devices under high temperatures can cause irreversible deterioration of certain components they include. For example, the components of an electronic device such as a control module for an integrated light source (such as an LED for “Light Emitting Diode”) can be degraded if they operate when the temperature is above 60 ° Celsius, approx. However, in actual use, it is common for the sun to heat the glazing to temperatures up to approximately 90 ° C, at the heart of its thickness.

This is why, we can consider triggering the shutdown of the supply of all or part of the integrated electronic devices, as soon as the temperature exceeds a given value. Electronic equipment thus put out of operation would thus be protected from the effects of a high temperature. In return, the user would no longer benefit from all the functionalities theoretically offered by his glazing as long as the temperature in the glazing has not sufficiently dropped to an acceptable level, below which the functioning of the electronic device could be restored.

Document WO 201586683 discloses a motor vehicle roof glazing made of laminated glass with two sheets of external and internal glass, as well as intermediate sheets. This roof glazing includes a light transmission control system and light emitting diodes integrated into the glazing. It also includes passive temperature regulation means which aim to limit the occurrence of excessively high temperatures in the glazing by the use of an absorbent material in the external part of the glazing or by the use of filters reflecting radiation. infrared in this same external part.

This type of system therefore makes it possible to passively prevent significant heating of the glazing. Despite this, if the temperature reaches a high value inside the glazing, the disturbance of the functioning of electronic equipment or their deterioration cannot be prevented. Passive warming prevention systems provide no solution in this case.

Summary of the invention

The invention aims to eliminate, or at least mitigate, all or part of the disadvantages of the aforementioned prior art.

To this end, a first aspect of the invention provides a motor vehicle glazing comprising a first sheet of glass, a second sheet of glass and a plurality of interlayer sheets of polymer material arranged between the first and the second sheet of glass, as well that at least one electronic device encapsulated in the intermediate layers and adapted to perform at least one electronic function, said glazing further comprising a cooling system encapsulated in the intermediate sheets and adapted to cool the electronic device, selectively, when the temperature of the glazing is greater than a first determined temperature threshold.

Thanks to the invention, it is possible to cool the glazing in its thickness as soon as a threshold temperature is exceeded. In particular, cooling targets the electronic equipment integrated into the glazing and therefore makes it possible, firstly, to prevent them from suffering damage due to high heating and secondly to guarantee the user the possibility of continuing to use the glazing functionalities. which depend on this equipment whatever the sunshine conditions of the glazing concerned.

Embodiments taken individually or in combination, further provide that:

- The glazing may further include a temperature sensitive sensor which is encapsulated in the intermediate sheets and is adapted to activate the cooling system when the temperature of the glazing is above the determined temperature threshold.

- The cooling system can be a Peitier effect system comprising a first plate of conductive material, called cold plate, arranged to be cooled by heat transfer, and a second plate of conductive material, said hot plate, arranged to evacuate the heat transferred from the first plate; the cold plate can be located at a relatively small distance from the electronic device to cool said electronic device by thermal conduction; and the hot plate can be located at a distance from the electronic device that is reiatively large to evacuate heat in the glazing without heating said electronic device.

- The cold plate can be a plate made of ceramic material.

- the hot plate can be encapsulated in the intermediate sheets, at a distance greater than or equal to two centimeters from all your electronic devices integrated into the glazing.

- The plurality of sheets of polymeric material can comprise at least one sheet of polyvinyl butyral (PVB).

- The electronic device can be a reading or reception lighting type device, or a device for controlling an active diffusive film.

- The glazing may further include one or more screen prints arranged to conceal the electronic devices and the cooling system.

In a second aspect, the invention also relates to a motor vehicle comprising glazing according to the first aspect, for example as roof glazing or windshield.

Brief description of the figures

Other characteristics and advantages of the invention will become apparent on reading the description which follows. This is purely illustrative and should be read in conjunction with the accompanying drawings in which:

[Fig. 1] is a schematic representation of a motor vehicle which comprises roof glazing according to the prior art;

[Fig. 2] is a schematic representation of the structure of a motor vehicle roof glazing according to the prior art; and, [Fig. 3] is a schematic representation of the structure of a motor vehicle roof glazing according to the invention.

[Fig. 4a] is a top view of the arrangement of the elements of a cooling system and of an electronic module in a glazing of the roof of the motor vehicle according to the invention.

[Fig. 4b] is a sectional view of the arrangement of the elements of a cooling system and of an electronic module in a glazing of the roof of the motor vehicle according to the invention.

Description of the embodiments

In the description of embodiments which follows and in the figures of the appended drawings, the same or similar elements bear the same numerical references in the drawings.

FIG. 1 shows a motor vehicle 101 which comprises a roof glazing 201 in itself conforming to the existing art, and to which the invention can be applied. Figure 2 schematically illustrates the detailed structure of such roof glazing. In particular, it shows a sectional view of a portion of the roof glazing 201 according to section 102 as illustrated in FIG. 1.

As will now be described in more detail, the roof glazing 201 incorporates several electronic devices which allow it to perform certain functions in response to a command.

The roof glazing 201 is composed of an outer glass sheet 202 which can be clear (that is to say without any particular tint), on the one hand, and an inner glass sheet 204 which can be tinted , on the other hand. The term “exterior” means the part of the glazing intended to be outside the vehicle (designated by “EXT” in the figure) and by “interior” the portion of the glazing intended to be located in (on the edge of) the passenger compartment of the vehicle (designated by "INT" in the figure). Glass is generally simple, but can also be processed (e.g. tempered).

Between the two glass sheets 202 and 204 are located one or more intermediate sheets 203 made of polymer material, for example polyvinyl butyral (PVB), polyethylene terephthalate (PET), EVA ethylene vinyl acetate (EVA) or methacrylate resins which form the heart of the roof glazing 201. The term "heart of the glazing" means the whole part located at the center of the total thickness e of the roof glazing 201, between the two sheets of glass 202 and 204. The PVB is a polymer material well known to those skilled in the art and commonly used for the manufacture of automotive glazing. It makes it possible in particular to form a glass / PVB lamination offering resistance and flexibility properties particularly suited to the requirements of the automotive field, in particular of safety and of maintaining visibility in the event of an impact by a foreign body (for example a stone). For example, roof (or roof) glazing but also windshields for motor vehicles generally comprise at least one such PVB interlayer sheet.

The intermediate sheets 203 also encapsulate one or more electronic devices. More precisely, as has already been said in the introduction, the electronic devices in question are placed within the different layers (/.e. The intermediate sheets) which form the glazing core. This equipment is therefore encapsulated in PVB sheets where they keep a fixed position and are protected from the outside environment (weather, small shocks, etc.).

In the example shown, the heart of the glazing thus comprises a device called reading module 214 and an active diffusive film 206. As shown in the figure, the reading module 214 comprises a glass plate 208 which supports an electronic module 210 of control, and several light sources including the two light-emitting diodes 211 shown, of LED type for example, as well as possibly a device for displaying a light pictogram 212. These various elements are obtained by conventional deposition techniques on the plate 208. The support plate 208 is also partially covered with a thin transparent metal oxide layer which makes it possible both to supply the components of the light source type which it supports but also to allow the operation of a sensor. capacitive.

In fact, the electronic module 210 integrates inter alia a capacitive sensor which emits a signal which is transported by the metal oxide layer on the surface of the plate 208 and which is disturbed, if necessary, by the approach of a user's finger at the level of the interior surface of the glazing 201. The reading module 214 therefore offers both lighting functions and a touch sensor function which makes it possible to control this lighting, to activate it or not. The user, in this case a passenger at the rear of the vehicle, for example, can control the lighting so, for example, that they can read in optimal conditions whatever your ambient natural lighting conditions. The luminous pictogram display device 212 can display a serigraphed pictogram which allows a user to locate where to press to use the touch sensor to control the reading light.

In addition, the electronic module 210 also includes a temperature-sensitive sensor of the thermocouple type which allows it to react continuously to the temperature in the glazing, for example at the heart of the glazing.

As already mentioned in the introduction, a certain level of protection on the basis of the measurements made by this sensor could consist in deactivating your electronic equipment integrated into the glazing when the temperature is too high and risks causing damage to the electronic device in operation . In particular, as soon as the measured temperature is higher than a determined threshold value, the power supply to each electronic device, or at least the most sensitive, could be cut to prevent them from suffering potentially irreversible damage. But we will see later what alternative and more advantageous solution the invention provides to this technical problem, thanks to the cooling system which is proposed.

The active diffusive film 206 makes it possible to modify your optical properties of the roof glazing 201. It can switch from a transparent state to a translucent state (as they have already been described above) depending on whether it is powered or not. More specifically, it is translucent if it is not powered and it is transparent if it is powered, that is to say if it is subjected to a certain electrical voltage. As a result, the film is by default in its translucent state when its power is cut (especially when the vehicle is not in use). This provides protection from viewing by third parties in the vehicle, and also helps reduce the temperature rise inside the vehicle due to solar radiation when the vehicle is parked outdoors.

The two glass sheets 202 and 204 are serigraphed, for example with black serigraphs 205a and 205b, respectively located on the periphery of the interior face of the exterior glass sheet 202 and on the periphery of the interior face of the interior glass sheet 204 These serigraphs for example form an outline of the roof glazing as a whole. The serigraphy 205b notably allows good adhesion of the glazing to the adhesive which makes it possible to assemble it with the rest of the vehicle. In addition, the two screen prints 205a and 205b make it possible to conceal all or part of the electronic equipment integrated into the roof glazing 201 from the eyes of people located in or outside the vehicle.

The reading module 214 and the active diffusive film 206 are respectively supplied via two separate supply systems 209 and 207 which allow the routing of an electric current from one (or more) supply source (s) located further in the motor vehicle up to the electronic device concerned, inside the glazing. It can for example be wires or tracks made of an electrically conductive material, which are encapsulated in the stack of PVB interleaves.

In the example of roof glazing shown in FIG. 2, in addition, a layer with low thermal emissivity 213 has been deposited on the inner face of the inner glass sheet 204. This layer provides thermal insulation, making it possible to reduce the entry of heat into the passenger compartment when the outside temperature is high and the retention of heat in the passenger compartment of the vehicle when the outside temperature is low.

Referring to Figure 3, Figure 4a and Figure 4b, there will now be described an embodiment of a motor vehicle window according to embodiments of the invention, for example a roof window.

In particular, Figure 3 schematically illustrates the detailed structure of an example of such roof glazing. Those skilled in the art will appreciate that the invention is not limited to this example, and may in particular find applications in other glazing, such as a windshield. Figures 4a and 4b illustrate, respectively in top view and in sectional view, the arrangement in space of the various elements integrated into the glazing of Figure 3 between which heat transfers occur. The section of Figure 4b is made in the section plane A-A shown in Figure 4a. These representations are purely illustrative and those skilled in the art will be able to arrange these different elements to produce the heat exchanges as described above.

The roof glazing 301 shown differs from a roof glazing 201 according to the prior art in that it incorporates, in addition to the electronic devices which allow it to perform certain functions called electronic functions, a cooling system 302.

The cooling system 302 used is for example a device of the Peltier effect module type, although the invention is not limited to this example and can use another type of cooling system. The principle of a Peltier effect module is based on a thermoelectric effect known per se to those skilled in the art, which makes it possible to transfer thermal energy (heat) from a first conductive material to a second different conductive material of the first conductive material. Such a module comprises, for example, two plates of conductive materials linked together by specific electrical junctions and which, when a current flows in the circuit thus formed, cools a plate while releasing the heat absorbed at the level of the other plate .

In the example shown, the plate 302b of the Peltier effect module is intended to absorb heat and is therefore called "cold plate" in the following. It is preferably located in the immediate vicinity of the electronic module 210 to be protected, so that it can be cooled by thermal conduction when the Peltier effect module is in operation. In FIG. 4b, the absorption of heat is represented diagrammatically by the arrow 401. It is, for example, a ceramic plate, which has good thermal conduction properties and is relatively easy to implant, or in any other material with equivalent properties. It is powered through the 303b power system.

The plate 302a of the Peltier effect module is intended to dissipate the heat transferred from the cold plate 302b by the Peltier effect. This plate 302a is called “hot plate” in the following. Preferably, it is located in a position far enough from the electronic devices integrated into the glazing to dissipate the heat without said devices being affected by the heat supply which occurs locally at the level of the plate. The dissipation of heat, in an area far enough away from the electronic module 210 to avoid heating it, is represented diagrammatically by the arrows 402 in FIG. 4b. PVB being a thermally insulating material, a distance of a few centimeters (for example greater than two centimeters) is generally sufficient to avoid such an effect. In one embodiment, as it appears in FIG. 3 and FIG. 4a, the hot plate 302a is offset, in the horizontal plane for example, relative to the cold plate 302b to guarantee this sufficient distance. Such a shift between the two plates is possible without altering the operation of the Peltier effect module, if a sufficient overlap area 320 is left between the cold plate and the hot plate in order to allow heat exchanges between the two plates which participate in the 'Peltier effect.

Those skilled in the art will appreciate that, in the example shown, it is the electronic module 210 for controlling the reading module 214 which is cooled. This thus makes it possible to keep this reading module in operation despite an overall temperature of the glazing greater than approximately 60 ° C., and therefore whatever the sunshine conditions to which the glazing is exposed, thanks to the cooling that the cooling system provides. locally at the level, for example, of light sources (/.e., LEDs) which are sensitive electronic devices, which must not operate at a temperature above about 60 ° C. However, such a cooling system can be associated with any other electronic device integrated into a glazing. For example, in a case where the active diffusive film is controlled by an electronic module also encapsulated in your PVB interleaves, this can also be cooled by another Peltier effect module so as to maintain the operability of the function linked to this active diffusive film despite an average temperature in the glazing generally higher than the acceptable limit, thanks to the cooling provided locally by such a Peltier effect module or any other technically equivalent cooling system.

Finally, a person skilled in the art will appreciate that as many cooling systems can be integrated into the glazing as necessary to cool all of your integrated electronic devices which are sensitive to the effects of the rise in temperature when they are in operation. . These cooling systems must only satisfy the conditions of placement within the glazing in order to guarantee that the cold plate of each Peltier effect module is located at a relatively close distance from the electronic equipment to cool you by thermal conduction, then that and the hot plate is located at a distance relatively distant from all your electronic devices integrated into the glazing to allow the heat to be dissipated in the thickness of the glazing without heating any of the sensitive electronic devices which are integrated there.

In addition, the number of electronic devices integrated into a glazing unit as well as their exact location can vary widely from one embodiment to another. Those skilled in the art will then be able to arrange each cooling device encapsulated in the PVB sheets in a suitable manner to ensure the cooling of one or more pieces of equipment in the event of high heat.

Furthermore, in the example shown, similar to glazing according to the prior art, the electronic module 210 incorporates a temperature-sensitive sensor, for example a sensor of the thermocouple type. Thanks to such a sensor, it is possible to automatically trigger the activation of the cooling device 302 in response to a rise in temperature in the glazing which creates a risk of damage to the protected electronic device. More specifically, the Peltier effect module can be activated or not depending on whether the temperature in the glazing, for example at the level of the environment of the integrated device to be protected, is greater than or not above a given temperature threshold. It is indeed not necessary to cool the glazing permanently when it remains at a low temperature implying no risk of damage to the electronic devices. Thus, advantageously, no energy is used to power the cooling device when its action is not useful. On the other hand, its activation makes it possible to regulate the temperature in the glazing and in particular to preserve one or more electronic equipment from any degradation and to guarantee their continuous operation. All the electronic functions offered by the glazing remain accessible whatever the circumstances of its use.

Another type of temperature-sensitive sensor can be used instead of or in addition to a thermocouple, such as a resistance with positive temperature coefficient (PTC) or negative temperature coefficient (NTC), in particular. In addition, the temperature sensor used can be arranged outside the electronic module 210 to be protected, elsewhere in the glazing, and / or in another functional module than the electronic module to be protected. Of course, the closer the sensor is to the device to be protected, the better the activation of the cooling system responds to the actual temperature at this device.

Those skilled in the art will also appreciate that the example of roof glazing is a non-limiting example. Any vehicle glazing of the laminated glazing type formed from glass sheets and PVB can integrate such a cooling device to cool, if necessary, the electronic equipment that the glazing integrates.

In summary, the invention makes it possible to maintain at all times a temperature low enough to maintain in operation, without risk of damage, an electronic device so that it performs its function independently of the conditions of sunshine and exposure of the glazing to sunshine.

In an alternative implementation of the method (not shown), the intensity of the cooling (/.e. The control of the Peltier effect module) may be dependent on the temperature of the glazing. This can be achieved by a plurality of thermocouples associated with a voltage or multiple current generator to activate the cooling system with voltages whose amplitude increases with the temperature of the glazing. Thus, if for example the threshold value from which cooling is activated is 55 ° C, the cooling is weak between 55 ° C and 65 ° C, moderate between 65 ° C and 75 ° C and strong between 75 ° C and 85 ° C. This cooling intensity differentiated as a function of temperature makes it possible to adjust the effective energy consumption for the operation of the Peltier effect module to the cooling need actually necessary for the preservation of one or more integrated electronic equipment.

The present invention has been described and illustrated in the present detailed description and in the figures of the appended drawings, in possible embodiments. The present invention is not limited, however, to the embodiments presented. Other variants and embodiments can be deduced and implemented by a person skilled in the art on reading this description and the attached drawings.

In the claims, the term include or include does not exclude other elements or other steps. A single processor or more than one other unit can be used to implement the invention. The various features presented and / or claimed can be advantageously combined. Their presence in the description or in different dependent claims does not exclude this possibility. The reference signs should not be understood as limiting the scope of the invention.

Claims (10)

1. Glazing (301) of a motor vehicle comprising a first sheet of glass (202), a second sheet of glass (204) and a plurality of interlayer sheets (203) of polymer material arranged between the first and the second sheet of glass, as well as at least one electronic device (214) encapsulated in the intermediate layers and adapted to perform at least one electronic function, said glazing further comprising a cooling system (302) encapsulated in the intermediate sheets and adapted to cool the electronic device , selectively, when the glazing temperature is above a first determined temperature threshold. 2. Motor vehicle glazing according to claim 1, further comprising a temperature sensitive sensor (210) which is encapsulated in the intermediate sheets and is adapted to activate the cooling system when the glazing temperature is above the determined temperature threshold. . 3. Motor vehicle glazing according to claim 1 or claim 2, wherein the cooling system is a Peltier effect system comprising a first plate of conductive material, called cold plate (302b), arranged to be cooled by heat transfer , and a second plate of conductive material, called a hot plate (302a), arranged to dissipate heat transferred from the first plate, in which the cold plate is located at a relatively small distance from the electronic device for cooling said electronic device by conduction thermal, and wherein the hot plate is located at a relatively large distance from the electronic device for removing heat in the glazing without heating said electronic device. 4. Motor vehicle glazing according to claim 3, wherein the cold plate is a plate made of ceramic material. 5. Motor vehicle glazing according to claim 3, in which the hot plate is encapsulated in the intermediate sheets, at a distance greater than or equal to two centimeters from all the electronic devices integrated into the glazing. 6. Glazing according to any one of claims 1 to 5, wherein the plurality of sheets (203) of polymeric material comprises at least one sheet of polyvinyl butyral, PVB. 7. Motor vehicle window according to any one of claims 1 to 6, wherein the electronic device is a reading device type reading light or home lighting, or a device for controlling a diffusive active film. 8. Motor vehicle window according to any one of claims 1 to 7, further comprising one or more screen prints arranged to conceal the electronic devices and the cooling system. 9. Glazing according to any one of claims 1 to 8, further comprising a plurality of thermocouples associated with a voltage generator or multiple current to activate the cooling system with an intensity which depends on the temperature of the glazing. 10. Motor vehicle comprising glazing according to any one of claims 1 to 9, for example as roof glazing or windshield