Suction fan for headlights of a motor vehicle

Description

[0001] The invention relates to an assembly comprising a headlight mounted on a motor vehicle and an air extractor arranged in said headlight

[0002] Patent applications US2018073701 A1 and FR2779804 A1 present motor vehicle headlights with a fan capable of creating air movement in the headlight.

[0003] To increase the efficiency of headlamps or light modules in headlamps, and in particular motor vehicle headlamps, spatial light modulator components can be used to form selectively activatable segmented beams. Light source matrices are an example of spatial light modulator components. However, these matrices heat up considerably due to their number and the increase in temperature quickly degrades their performance.

[0004] Other examples of spatial light modulator components include LCD screen components or micromirror matrices (also known as DMDs for digital micromirror devices).

[0005] It would therefore be interesting to integrate spatial light modulator components into a projector, such as MEMS (for "microelectromechanical systems"), micro-mirror matrices, LCD screens or lasers.

[0006] However, the operating temperature limit for such components is quite low (around 85°C), so it is impossible to use them under normal projector temperature conditions. Indeed, a projector is a closed assembly comprising heating elements and positioned near a motor, and the temperature inside the projector can reach high values, and the operating temperature limit of the components is quickly exceeded.

[0007] Additionally, such components require a sealed environment, particularly against external particles. Indeed, the presence of external particles can significantly reduce the performance of the electronic components in the projector. The projector must therefore be protected from the external environment.

[0008] To meet these constraints, there are projectors comprising heat exchangers coupled with fans positioned near the sensitive components to cool them directly.

[0009] However, the first disadvantage of such projectors is the number of additional manufacturing steps and the addition of a large number of additional components on small surfaces during manufacturing.

[0010] A second disadvantage is that repairing such a system, in the event of a fan failure, is complicated. It is therefore preferable to replace the entire projector or the housing including the spatial light modulator components, which involves additional costs.

[0011] A general object of the invention is to provide a projector solution improving existing solutions, and allowing the use of heating components without the risk of exceeding their operating temperature limit.

[0012] More specifically, a first object of the invention is to find a compromise allowing the use of spatial light modulator type components within a projector while maintaining their temperature below their operating limit value while guaranteeing the projector's sealing.

[0013] A second object of the invention is to provide a solution for a projector that is simple to implement and at low cost.

[0014] According to a first aspect, the invention relates to an assembly comprising a projector mounted on a vehicle and an air extractor according to claim 1.

[0015] In one embodiment, the external particle sealing system comprises at least one closure means configured to assume an open position and a closed position. The open position allows fluid communication between the air outlet and the air inlet and the closed position makes it possible to prevent at least the passage of external particles between the air outlet and the air inlet.

[0016] In one embodiment, the air extractor comprises a device for controlling the at least one sealing means.

[0017] In one embodiment, the at least one sealing means is arranged in the air outlet and / or in the air inlet.

[0018] In one embodiment, the at least one closure means is movable between the open position and the closed position by rotation along an axis or by translation.

[0019] In one embodiment, the exterior particle sealing system comprises, between the ventilation chamber and the air outlet, a channel having a curvature.

[0020] In one embodiment, said channel has a slope when the air extractor is integrated into a projector for the evacuation of liquid towards the air outlet.

[0021] In one embodiment, the air outlet comprises a grille.

[0022] In one embodiment, the projector further comprises a projector air inlet optionally comprising an air filter.

[0023] In one embodiment, the air extractor is arranged on an upper and / or rear portion of the projector.

[0024] In one embodiment, the projector air inlet is arranged on a lower and / or front portion of the projector.

[0025] In one embodiment, the air extractor is removably attached to the projector.

[0026] In one embodiment, the projector further comprises at least one optical module comprising at least one electronic component and at least one cooling system for said electronic component, said cooling system comprising only a conduction cooling system. The at least one electronic component may be a spatial light modulator.

[0027] According to a third aspect, the invention relates to a method for controlling an assembly according to the invention, in which the air extractor comprises a movable closure means. Said method comprises the following steps: activating the fan then opening the at least one closure means. There figure 1 is a diagram of the front of a vehicle comprising a headlight comprising an air extractor according to a first embodiment of the invention. The figure 2A represents an air extractor according to an embodiment of the invention in which the sealing system comprises a hatch. The figure 2B represents the air extractor illustrated on the figure 2A in which the hatch is in the closed position. The figure 2C represents the air extractor illustrated on the figure 2A in which the hatch is in the open position The figure 2D represents a variant of the first embodiment of the air extractor according to the figure 2A in which the hatch is arranged at the entrance to the ventilation chamber. The figure 3A represents an air extractor according to a second embodiment of the invention in which the sealing system comprises at least one flap and in which the flap is in the closed position. The figure 3B represents the air extractor illustrated on the figure 3A in which the shutter is in the open position. The figure 4 represents an air extractor according to a third embodiment in which the sealing system is a channel extending from the outlet of the ventilation chamber.

[0028] In the remainder of the description, the following terms are defined and may be understood as follows: We define by the longitudinal direction the direction oriented from front to rear relative to a motor vehicle, the adjectives front and rear being defined relative to the usual movement of the vehicle. We define by transverse direction the direction perpendicular to the longitudinal direction and oriented from right to left of a motor vehicle. The two longitudinal and transverse directions define a horizontal plane. The vertical direction is perpendicular to the horizontal plane, oriented upwards. These same directions will be used for the description of a headlight, considering the headlight as it would be positioned within a vehicle.

[0029] The adjectives “superior” and “inferior” will thus be used in relation to the vertical direction defined above.

[0030] The term "external particles" means an element present in the environment outside the projector that may reduce the performance of components present in the projector upon contact. External particles may include, but are not limited to, dust, water, oil splashes, washing product splashes or leaves.

[0031] The concept of the invention is based on the use of an air extractor, arranged at the level of a projector, allowing the hot air present in the projector to be evacuated to replace it with fresh air, to reduce the average temperature of the air inside a projector and consequently the temperature of the components positioned inside the projector. This principle is illustrated schematically by the figure 1 , which represents a headlight 103 mounted on a motor vehicle 101 equipped with an air extractor 102 according to one embodiment of the invention. Advantageously, the attachment of such an air extractor 102 to the headlight 103 is removable, to allow its replacement in the event of failure.

[0032] The projector 103 comprises at least one optical module 105. This optical module comprises one or more temperature-sensitive components, comprising, for example, at least one component of the spatial light modulator type, a semiconductor component, a MEMS, a micro-mirror matrix, a liquid crystal screen or a laser.

[0033] Advantageously, this optical module comprises a cooling system specific to the electronic component(s): however, as the optical module is integrated into a projector comprising an air extractor according to one embodiment of the invention, which limits its average temperature, this cooling system specific to it can be simple and comprise only cooling by conduction and natural convection. Thus, the optical module does not comprise a fan. It is thus simplified compared to conventional optical modules comprising the same electronic components. Naturally, the invention remains compatible with these traditional optical modules comprising their own cooling system with fan(s).

[0034] By "natural convection" is meant convection which is not forced, i.e. carried out without a fan or any other similar means allowing a flow of air to be imposed locally in contact with or near the optical module.

[0035] The headlight 103 further comprises a lens 106, arranged flush or projecting relative to the bodywork 107 of the vehicle 101.

[0036] The air extractor 102 is arranged on or through a wall of the projector 103. The air extractor can thus provide fluid communication between the inside and the outside of the projector 103. The air extractor 102 is arranged to allow the extraction of air inside the projector to the outside of the projector 103. In one embodiment, the projector comprises an air inlet 104 of the projector. The hot air inside the projector is thus replaced by cooler air and the overall temperature of the air inside the projector decreases.

[0037] The air extractor 102 is preferably arranged on the upper part of the projector 103. Indeed, since hot air is less dense than cold air, the air inside the projector 103 is hotter in the upper part of the projector 103 than in the lower part. The arrangement of the air extractor 102 in the upper part of the projector 103 thus advantageously makes it possible to extract the hottest air towards the outside of the projector and thus promotes the lowering of the temperature of the air inside the projector 103.

[0038] In one embodiment, the air extractor 102 comprises an air guide whose inlet is arranged on the upper part of the projector 103. The air extractor 102 could then be arranged on a lower part or an intermediate part located between the lower part and the upper part of the projector 103, the air guide making it possible to bring the hot air located in the upper part of the projector 103 to the extractor.

[0039] In one embodiment, an air inlet 104 of the projector is arranged on the lower part of the projector 103. The air inlet of the projector 104 may be arranged on the lower surface 108 of the projector. Preferably, the air inlet of the projector 104 is located below a horizontal plane passing through the air extractor 102.

[0040] In one embodiment, the air inlet of the headlight 104 is arranged on the front part of the headlight 104, that is to say the part closest to the glass 106 of the headlight 103. Such an arrangement of the air inlet of the headlight 104 advantageously allows cooler air to enter the interior of the headlight 103, in particular by moving the air inlet of the headlight 104 away from the engine of the vehicle 101, generally located at the rear of the headlight 103.

[0041] In one embodiment, the air inlet of the projector 104 comprises an air guide whose inlet is arranged on the front part and / or on the lower part of the projector 103.

[0042] The air inlet of the projector 104 may comprise an air filter. The air filter advantageously allows the passage of air from the outside to the inside of the projector 103 by preventing external particles from entering the interior of the projector 103 through the air inlet of the projector 104.

[0043] An example of an air extractor 201 according to a first embodiment is described below with reference to figures 2A , 2B And 2C .

[0044] The air extractor 201 comprises an air inlet 203 and an air outlet 214, more particularly shown in the figure 2C The air extractor 201 also comprises a ventilation chamber 210. Said ventilation chamber 210 is advantageously arranged between said air inlet 203 and said air outlet 214 of the air extractor 201. The ventilation chamber 210 comprises a fan 202. By fan, we mean any means for generating an air flow between the air inlet 203 and the air outlet 214.

[0045] The fan 202 may be a radial fan, an axial fan, or any other type of fan. In one embodiment, the fan 202 is designed to generate an airflow at the air outlet having a speed substantially equal to 5 meters per second. In one embodiment, the fan 202 is designed to generate an airflow at the air outlet of between 100 and 500 L / min.

[0046] As illustrated by the figure 2B , the air extractor 201 is arranged in the rear and upper part of a projector 213, in a manner similar to the diagram of the figure 1 The air inlet 203 is arranged to be positioned inside the projector 213. The air outlet 214 is arranged to be outside the projector 213. The fan 202 thus makes it possible to suck the internal hot air inside the projector 213 through the air inlet 203 and to expel it towards the outside of the projector 213 and the air outlet 214 of the air extractor.

[0047] The air extractor 201 also comprises a sealing system, at least against external particles. In a non-limiting embodiment, the sealing system is also airtight. The sealing system against external particles makes it possible to prevent external particles present in the air outside the projector 213 from penetrating inside the projector 213 when the fan is off or when the fan is not activated.

[0048] Indeed, when the air extractor 201 is operating, a through air flow is generated from the air inlet 203 to the air outlet 214 of the air extractor 201. This through air flow prevents external particles from passing through the extractor to the inside of the projector. However, when the fan 202 is switched off, no air current is generated and it is therefore important for the preservation of the components present in the projector to close the extraction system so that no dust enters the projector through the air extractor.

[0049] In one embodiment, the air extractor does not include an air filter, which avoids creating too much resistance to the air flow.

[0050] A first example of a sealing system is illustrated by the figure 2A In this first embodiment, the sealing system comprises a sealing means 206. The sealing means 206 may be located in the ventilation chamber 210, in the air inlet 203 or in the air outlet 214. The sealing means 206 may be a hatch covering the entire section of the air extractor.

[0051] The shutter means 206 is designed to be able to take or to be able to move between two positions: an open position ( figure 2C ) allowing fluid communication between the air inlet and the air outlet of the air extractor and a closed position ( figure 2B ) to prevent at least the passage of external particles between the air outlet and the air inlet.

[0052] In one embodiment, the closure means 206 is movable between two limit positions: the closed position and the open position.

[0053] In the closed position, the sealing means 206 may cover a section of the air extractor so as to prevent at least external particles from passing through this section. Said section may be located in the ventilation chamber 210, in the inlet or the outlet of the air extractor.

[0054] The sealing means 206 may be a hatch made of gas-impermeable material or of air-permeable material that is impermeable to external particles.

[0055] The sealing means 206 may be movable between a closed position ( figure 2B ) and an open position ( figure 2C ) by a translational movement or by a system of shutter(s).

[0056] The air extractor 201 also comprises an air guide 204. The air guide 204 makes it possible to fluidly connect the air inlet 203 of the air extractor with the ventilation chamber 210. The air guide 204 thus makes it possible to provide an air extractor 201 comprising an air inlet 203 oriented towards the upper side of the extractor. This air guide 204 thus advantageously makes it possible to place the air inlet 203 towards the top of the projector. In this way, the air guide 204 allows the suction of air from the projector in the highest possible position, therefore the hottest air 211, rather than the cooler air 212 present in the lower part of the projector 213. The air guide 204 comprises a longitudinal channel or pipe.In the embodiment, the air guide 204 makes it possible to form a tortuous path for the air, which also helps to limit the possibilities of possible external particles passing from the outside to the inside of the projector, and therefore contributes to the sealing function.

[0057] The air extractor 201 may also comprise seals 208 to ensure sealing between the extractor 201 and the projector 213 and / or between the walls of the extractor 201 and the sealing means 206.

[0058] There figure 2D illustrates a variant of the first embodiment, in which the closure means 206 is arranged at the entrance to the ventilation chamber 210. The two variant embodiments can also be combined.

[0059] In this first embodiment, the projector further comprises a control device 209 for the air extractor 201, shown in the figures 2A And 2D. This control device may comprise an activator, arranged to control the opening and closing of the at least one closure means 206. The activator 209 may comprise a motor or an animated arm for moving the closure means 206. The control device may, in addition, comprise a processor 207 and / or a printed circuit. The processor may be connected to the activator 209 by a communication means, in order to control the closure means via the activator.

[0060] The control device is configured to trigger the operation of the air extractor when the engine of the vehicle 101 is started, and to stop it when the engine is stopped.

[0061] THE figures 3A And 3B represent an air extractor 301 according to a second embodiment, respectively in open and closed configuration.

[0062] In this embodiment, the air extractor 301 comprises at least one closure means 306 which can be moved in rotation. In particular, the closure means 306 can be moved in rotation around a pivot 309, oriented in the transverse direction. This closure means 306 is designed to, in the closed position represented by the figure 3A , simultaneously close the inlet and outlet of the ventilation chamber 310. In the open position represented by the figure 3B , it simultaneously opens the inlet and outlet of the ventilation chamber 310. Alternatively, this sealing means could open and close the air inlet 303 and the outlet 314 of the air extractor 301.

[0063] The closing means 306 is of sufficient length on either side of the pivot 309 to, in the closed position, allow the section of the inlet of the ventilation chamber 310 and the section of the outlet of the ventilation chamber 310 to be covered.

[0064] The ventilation chamber 310 may include seals 308 disposed between the pivot 309 and the wall of the projector 313. The extractor 301 may also include a seal 308 between the ventilation chamber and the walls of the projector.

[0065] The sealing means 306 may comprise a surface 305 which is impervious to external particles and permeable to gases.

[0066] The air extractor 301 further comprises an air guide 304 designed so that the air inlet of the extractor 303 is oriented upwards or towards the upper face of the projector 313. Thus, the extractor 301 can suck in the hotter gases 311, rather than the cooler gases 312 located in the lower part of the projector.

[0067] In a third embodiment illustrated by the figure 4 , an air extractor 401 likewise comprises an air inlet 403, then an air guide 404 towards a ventilation chamber 410 equipped with at least one fan 402. In this embodiment, the sealing system comprises an outlet channel 405 having at least one curvature. This outlet channel 405 having at least one curvature is arranged between the ventilation chamber 410 comprising the fan 402 and the air outlet 414 of the air extractor 404. Alternatively, the outlet channel 405 may comprise several curvatures. Preferably, said outlet channel 405 comprises a curvature of between 150° and 200°, that is to say that it guides the air extracted by the air extractor 401 along a trajectory comprising such a significant curvature, before its exit from the extractor. Such a curve, approximately around 180°, allows the outlet channel 405 to direct the air outlet 414 towards the rear wall of the projector 413.Thus, the air outlet 414 is not oriented towards the vehicle engine. This orientation makes it impossible or very difficult, when the fan is switched off, for external particles to penetrate inside the headlight via the air extractor. The outlet channel 405 thus fulfills the sealing function. Alternatively, the sealing system could be implemented by any other channel having at least one curvature, not necessarily positioned at the outlet of the air extractor.

[0068] In one embodiment, the outlet channel 405 further comprises a filter or grid 415 near the air outlet 414. This grid makes it possible to slow down or stop external particles, which will tend to settle on this grid rather than traveling through the outlet channel 405.

[0069] The grid 415 covers the section of the outlet channel 405. Preferably, the grid completely covers the section of the outlet channel 405 at the air outlet 414. Preferably, the grid comprises a succession of flaps or wires. The spacing between each adjacent flap or between each adjacent wire is between 0.5 and 3 mm.

[0070] Preferably, the outlet channel 405 also extends over a sufficient length to ensure sealing against external particles of the air extractor 401. The outlet channel 405 may extend over a length at least greater than 25 mm and / or less than 200 mm.

[0071] The diameter or width of the section of the outlet channel 405 may be between 15 and 50 mm. The dimensions of the section of the outlet channel 405 contribute to the sealing of the air extractor 401, while allowing the passage of the air flow during operation of the fan 402.

[0072] The advantage of this solution is that it does away with the use of mechanical devices such as mobile shutters. Advantageously, this solution can also do without an air filter.

[0073] The outlet channel 405 may also be designed to, once mounted on the headlight 413 and on a vehicle, have a slope so that water which would be present in the outlet channel, for example following a projection or by condensation, is evacuated by gravity through the air outlet 414 of the extractor 401. The air outlet 414, when the air extractor is mounted on a headlight on a vehicle, is advantageously arranged at a lower height than the air outlet of the ventilation chamber 410.

[0074] Additionally, in all embodiments, the ventilation chamber is designed to have a slope relative to a horizontal plane. This slope allows, once the extractor is mounted on a vehicle headlight, to allow water to flow outwards on the walls of the ventilation chamber, without penetrating into the headlight. As shown in the figures 2A à 4 , the upper part of the ventilation chamber, arranged outside the projector, has a slope with a horizontal plane so as to evacuate the water. In these embodiments, water cannot stagnate in the air extractor, nor penetrate inside the projector.

[0075] The invention is not limited to the embodiments described. For example, any other means of closure may be envisaged. For example, a shutter may be movable in a movement other than translation or rotation, or in a translation in a direction other than that described in the first embodiment, or in a rotation around an axis oriented in a direction other than that described in the second embodiment.

[0076] In addition, the at least one closure means may comprise at least two or a plurality of flaps. In this case, the different flaps are configured to perform a rotational movement in a synchronized manner. Each flap is arranged to, in the closed position, cover a portion of the section of the air extractor. The flaps are arranged to, when they are all in the closed position, together completely cover the section of the air extractor. For example, in one embodiment, the at least one closure means comprises a double flap.

[0077] Additionally, in all embodiments, the air extractor comprises a control device, such as that described with reference to the first embodiment.

[0078] This control device can further implement a method for extracting air from a headlight, including in particular a method for activating the air extractor, automatically triggered when the motor vehicle is started, and automatically stopped when the motor vehicle engine is stopped. The headlight and / or the air extractor thus includes a movable shutter means, and includes hardware and / or software elements for implementing the air extraction method.

[0079] In an embodiment associated with an air extractor with a movable flap, as according to the first or second embodiment of the invention, the method of activating the air extractor advantageously comprises the following steps: activating the fan; then moving one or more shutters to reach an open position.

[0080] Preferably, the movement step is performed at least one second, preferably at least 3 or 4 seconds, very preferably between 3 and 6 seconds after the activation step has been performed. In this way, the activation of the fan causes the ventilation chamber to be overpressurized before the closure means opens. This overpressure advantageously ensures that no dust can enter the projector through the extractor when it is put into operation.

[0081] The step of activating the fan may be preceded by a step of receiving a control signal, for example a signal generated when the motor is switched on, is energized.

[0082] Similarly, the extractor deactivation process includes the following steps: moving the shutter means to the closed position; deactivating the fan.

[0083] Preferably, the deactivation step is performed at least one second, preferably at least 3 or 4 seconds, very preferably between 3 and 6 seconds after the execution of the movement step. In this way, it can be ensured that no dust can enter the interior of the projector through the extractor when it is stopped.

[0084] The moving step may be preceded by a step of receiving a control signal, for example a signal generated when the motor is switched off, is powered down.

Claims

1. Assembly comprising a headlight mounted on a vehicle and an air extractor (201; 301; 401) arranged in said headlight, said air extractor (201; 301; 401) comprising: - an air inlet (203; 303; 403) arranged inside the headlight, and an air outlet (214; 314; 414) arranged outside the headlight; - a ventilation chamber (210; 310; 410) disposed between said air inlet (203; 303; 403) and said air outlet (214; 314; 414) of the air extractor, said ventilation chamber (210; 310; 410) comprising a fan (202; 302; 402) arranged to produce a flow of air from the air inlet to the air outlet; and - a sealing system sealing against external particles; a part of the ventilation chamber (210; 310; 410) being arranged outside the headlight and comprising an upper part having a slope with respect to the horizontal plane, the air inlet (203; 303; 403) comprising an air guide (204; 304; 404) oriented on the upper side of the air extractor providing fluidic connection between the air inlet (203; 303; 403) and the ventilation chamber (210; 310; 410).

2. Assembly according to Claim 1, wherein the sealing system sealing against external particles comprises at least one shutoff means (206; 306) designed to assume: - an open position allowing fluidic communication between the air outlet and the air inlet; and - a closed position for preventing at least the passage of external particles between the air outlet and the air inlet.

3. Assembly according to Claim 2, comprising a device for controlling the at least one shutoff means (206; 306) .

4. Assembly according to Claim 2 or Claim 3, wherein said at least one shutoff means (206; 306) is arranged in the air outlet and / or in the air inlet.

5. Assembly according to one of Claims 2 to 4, wherein said at least one shutoff means (206; 306) is movable between the open position and the closed position in rotation about an axis or in translation.

6. Assembly according to Claim 1, wherein the sealing system sealing against external particles comprises, between the ventilation chamber and the air outlet, a channel having a bend.

7. Assembly according to the preceding claim, wherein said channel has a slope for the evacuation of liquid toward the air outlet.

8. Assembly according to Claim 6 or Claim 7, wherein the air outlet (414) comprises a grille (415).

9. Assembly according to one of Claims 1 to 8, characterized in that the air extractor (201; 301; 401) is arranged on an upper and / or rear part of the headlight.

10. Assembly according to one of Claims 1 to 9, characterized in that the headlight comprises an air inlet (104) arranged on a lower and / or front part of the headlight.

11. Assembly according to one of Claims 1 to 10, characterized in that the air extractor is removably fixed to the headlight.

12. Assembly according to one of Claims 1 to 11, characterized in that the headlight further comprises at least one optical module comprising at least one electronic component and at least one cooling system for cooling said electronic component, said cooling system comprising only a system for cooling by conduction.

13. Method of controlling an assembly according to one of Claims 1 to 12, said sealing system sealing against external particles comprising a movable shutoff means, characterized in that it comprises the following steps: - activating the fan; then - opening the at least one shutoff means.