METHOD FOR MANAGING A SYSTEM OF PIVOTING AERODYNAMIC DEFLECTORS FOR A MOTOR VEHICLE

Abstract

METHOD FOR MANAGING A SYSTEM OF PIVOTABLE AERODYNAMIC DEFLECTORS FOR A MOTOR VEHICLE The present invention relates to a method for managing a system of aerodynamic deflectors (4) mounted on a front bumper (2) and arranged in front of front wheels (6) of a motor vehicle (1), said system comprising two deflectors pivoting between: - an open position of the deflectors, in which each of said deflectors projects from the front bumper and is arranged opposite the corresponding wheel; and - a closed position of the deflectors, in which each of said deflectors is longitudinally retracted into the front bumper, remarkable in that said method ensures management of actuation of the pivoting of the deflectors as a function of a driving speed of the motor vehicle and as a function of at least one condition of pressing on a brake pedal (12) of said motor vehicle. (Figure to be published with the abstract: Figure 1)

Description

Title of the invention: METHOD FOR MANAGING A SYSTEM OF PIVOTING AERODYNAMIC DEFLECTORS FOR A MOTOR VEHICLE Technical field

[0001] The present invention relates to the field of motor vehicles, more particularly the field of aerodynamic deflector systems for motor vehicles. Prior art

[0002] Among modern motor vehicles, there are certain models incorporating air deflectors positioned protruding upstream of the front wheels. This arrangement of the deflectors acting as physical barriers in front of the front wheels promotes better air circulation and prevents turbulence near the wheels while the motor vehicle is moving.

[0003] One of the main advantages of these deflectors lies in the reduction of aerodynamic drag resulting in a gain in consumption, which is particularly important for electric traction motor vehicles, for which autonomy and energy efficiency are a major concern.

[0004] Published patent document WO 2011 / 126069 A1 discloses a front floor structure of a vehicle equipped with deflectors placed in front of the front tires, said deflectors having a pointed section forming a leading edge making it possible to adjust the air flow which circulates around the front floor while driving the motor vehicle.

[0005] However, although the deflectors disclosed in the document are effective in reducing turbulence under the floor of the motor vehicle, they do not adequately contribute to the cooling of the brakes of the motor vehicle. Indeed, during driving, these deflectors restrict the airflow directed towards the braking system, thus exposing components such as discs, brake pads and calipers to the risk of overheating, particularly in extreme conditions such as braking downhill or on mountain passes, especially when the vehicle is heavily loaded. Statement of the invention

[0006] The present invention aims to overcome at least one of the drawbacks of the aforementioned state of the art. More specifically, the invention aims to propose a solution making it possible to effectively reconcile the aerodynamic advantages of deflectors with the cooling requirements of motor vehicle brakes.

[0007] In this regard, the invention relates to a method for managing a system of aerodynamic deflectors mounted on a front bumper and arranged in front of the front wheels of a motor vehicle, said system comprising two deflectors pivoting between: - an opening position of the deflectors, in which each of said deflectors projects from the front bumper and is arranged opposite the corresponding wheel; and - a closed position of the deflectors, in which each of said deflectors is longitudinally retracted into the front bumper, remarkable in that said method ensures management of actuation of the pivoting of the deflectors as a function of a driving speed of the motor vehicle and as a function of at least one condition of pressing on a brake pedal of said motor vehicle.

[0008] According to one embodiment, the at least one condition for pressing the brake pedal of the motor vehicle comprises a number and / or a duration of pressing said brake pedal.

[0009] According to one embodiment, the actuation of the pivoting of the deflectors in the open position of said deflectors is conditioned by: - a driving speed of the motor vehicle greater than a lower limit speed Vj and by the absence of pressure on the brake pedal; or - a driving speed greater than a threshold speed Vs and when pressing the brake pedal includes a short pressing duration, said threshold speed Vs being at least twice greater than the lower limit speed Vj.

[0010] Advantageously, the short press duration corresponds to a press duration of less than two seconds.

[0011] According to one embodiment, the actuation of the pivoting of the deflectors in the closed position of said deflectors is conditioned by: - a motor vehicle driving speed lower than a lower speed limit Vi; or - pressing the brake pedal when the driving speed is between the lower limit speed Vi and a threshold speed Vs at least twice higher than said lower limit speed Vb and when detecting the presence of a speed bump on the road; or - at least two successive presses on the brake pedal, when the driving speed is higher than the threshold speed Vs.

[0012] According to one embodiment, the actuation of the pivoting of the deflectors in the closed position of said deflectors is conditioned by a rolling speed greater than the threshold speed Vs, and: - when at least two successive presses on the brake pedal occur over a period of less than or equal to five seconds, or - when each press of at least two successive presses includes a long press duration.

[0013] Advantageously, the long press duration corresponds to a press duration equal to at least two seconds.

[0014] According to one embodiment, the lower limit speed Vi is between 5 km / h and 15 km / h, and the threshold speed Vs is between 40 km / h and 60 km / h.

[0015] The invention also relates to a computer program comprising computer-readable code instructions, remarkable in that said program causes the computer to implement the method for managing an aerodynamic deflector system of a motor vehicle according to the invention, when said program is executed by a computer.

[0016] The invention also relates to a device comprising a recording medium readable by a computer, remarkable in that the computer program according to the invention is recorded on the recording medium.

[0017] The invention also relates to a motor vehicle, remarkable in that said motor vehicle is configured to execute the method for managing an aerodynamic deflector system of a motor vehicle according to the invention.

[0018] The measures of the invention are advantageous in that the method for managing the deflector system ensures the electrical control of the pivoting of the deflectors as a function of the conditions of pressure on the brake pedal (duration of pressure and number of pressures over a period) and in correlation with the driving speed of the motor vehicle.

[0019] Consequently, optimal cooling of the components of the braking system of the motor vehicle is ensured at all speeds, even in unfavorable driving conditions including the vehicle descending a steep slope. The invention thus makes it possible to prevent overheating of the brakes, thus guaranteeing their longevity, while optimizing the fuel consumption gain generated by the deflectors in the open position, and this, over the entire speed range of the motor vehicle. Brief description of the drawings

[0020] [Fig.l] schematically represents a perspective view of a motor vehicle according to the invention, comprising a system of aerodynamic deflectors pivotally mounted on a front bumper of said vehicle, their pivoting being managed by means of a management method according to the present invention;

[0021] [Fig.2] illustrates a perspective view of one of the two pivoting deflectors of [Fig.l], in the closed position in which said deflector is longitudinally retracted into the front bumper. Detailed description

[0022] For the purposes of the description, reference will be made to a direct orthonormal reference frame XYZ conventionally used in automobile design, in which the X axis designates the front-rear longitudinal direction of the vehicle, oriented towards the rear, the Y axis designates the transverse direction and is oriented towards the right of the vehicle, the Z axis designates the vertical direction, and is oriented upwards.

[0023] [Fig.l] represents a schematic view of a motor vehicle 1 according to the invention, comprising a front bumper 2 provided with two aerodynamic deflectors 4 arranged in front of front wheels 6.

[0024] The deflectors 4 are pivotable between an open position (as illustrated in [Fig.l]) and a closed position (visible in [Fig.2]). Each deflector 4 in the open position extends vertically (along the Z axis) and projects from the front bumper 2 so as to be arranged opposite the corresponding wheel 6. In contrast, the deflectors 4 in the closed position are longitudinally retracted into the front bumper 2 in a substantially horizontal manner.

[0025] The pivoting of the deflectors 4 is ensured by a system 3 comprising an actuator 8 linked to the deflectors 4 by a direct connection illustrated in dotted lines in [Fig.l], and making it possible to act mechanically and directly on said deflectors in order to control their pivoting. In this respect, the actuator 8 may comprise an electrically controlled pneumatic cylinder or an electric motor or any other suitable pivoting actuation means.

[0026] Preferably, the actuator 8 further comprises means for electrically controlling said actuator 8, the signal of which is dictated by a computer 10 of the motor vehicle 1.

[0027] Advantageously, the present invention proposes a method for managing the pivoting of the deflectors 4 in an efficient and more precise manner in order to combine the aerodynamic advantages of the deflectors 4 linked to the deflection of the air flow F (when they are in the open position), with the cooling requirements of the friction brake components of the motor vehicle.

[0028] To this end, the method according to the invention proposes to retract the deflectors 4 while taking into account possible stresses on the friction brakes by the brake pedal 12 of the motor vehicle 1. Thus, according to predefined scenarios which will be detailed below, the computer 10 is able to effectively control the actuation of the opening and closing of the deflectors 4.

[0029] Closing the deflectors 4 advantageously allows the brakes of the motor vehicle 1 to be cooled. It can be seen in [Fig.2] that the deflector 4 is completely retracted into a front diffuser 5 of the front bumper 2, the latter comprising in this respect a hollow part configured to receive and completely submerge the deflector 4, in order to ensure aerodynamic continuity in line with the diffuser 5, so that the air flow F generated by the rolling of the motor vehicle 1 allows cooling of its braking members.

[0030] With reference to figures 1 and 2, the system 3 for controlling the pivoting of the deflectors 4 comprises a connection from the brake pedal 12 and a speed sensor 14 of the motor vehicle 1, directly to the computer 10.

[0031] Advantageously, the method ensures the management of the actuation of the pivoting of the deflectors 4 as a function of a driving speed of the motor vehicle 1 transmitted by the speed sensor 14 and as a function of one or more conditions of pressure on the brake pedal 12.

[0032] Preferably, the method comprises taking into account the driving speed of the vehicle in combination with a verification of the conditions of pressing on the brake pedal 12, said conditions comprising a number and / or a duration of pressing on the brake pedal 12.

[0033] The method of the invention distinguishes two speed levels for driving the motor vehicle 1, comprising a lower limit speed Vi and a threshold speed Vs greater than at least twice said lower limit speed Vp. Preferably, the lower limit speed Vi is between 5 km / h and 15 km / h, and is more preferably equal to approximately 10 km / h, and the threshold speed Vs is between 40 km / h and 60 km / h, and is more preferably equal to approximately 50 km / h. The term “approximately” corresponds to ±20% of the nominal value referred to.

[0034] According to the invention, when the motor vehicle is traveling at a traveling speed lower than the lower limit speed Vb then the deflectors 4 are always retracted in the closed position, because said speed Vj is not high enough to provide a significant aerodynamic advantage. In addition, at this speed, the risk of hitting an obstacle (a sidewalk for example) is high, the retraction of the deflectors 4 is then desired to avoid damaging them.

[0035] When the vehicle 1 is traveling at a driving speed between the lower limit speed Vj and the threshold speed Vs, the computer 10 orders the opening of the deflectors 4 in the event of no pressure on the brake pedal 12. The computer 10 orders the retraction of said deflectors 4 in the event of pressure on the pedal 12 and upon detection of the presence of a speed bump on the road (such as a speed bump for example). For this purpose, the motor vehicle 1 is equipped with means for detecting the state of the roadway on which said vehicle is traveling, and / or said vehicle is connected to a geographical database which has the GPS coordinates of the speed bumps on the road.

[0036] Preferably, the retraction of the deflectors 4 in the event of detection of a speed bump is accompanied by a time delay after which the deflectors 4 are redeployed to the open position, this time delay being predefined (for example 10 seconds) to allow sufficient time for the vehicle to pass the speed bump. Alternatively, the redeployment of the deflectors 4 can also take place upon detection of acceleration of the vehicle or pressing the accelerator pedal, acting as confirmation of having passed the speed bump.

[0037] Otherwise, the deflectors 4 remain open for driving speeds between the lower limit speed Vi and the threshold speed Vs, because the risk of overheating of the braking members is not very high when the vehicle is traveling at a speed lower than the threshold speed Vs. Similarly, as long as no pressure on the pedal 12 is detected, the deflectors 4 remain deployed in the open position at a driving speed exceeding the lower limit speed Vp.

[0038] The deflectors 4 also remain open when the driving speed is higher than the threshold speed Vs and in the event of a short press on the brake pedal 12. Preferably, a press is considered to be “short” when it corresponds to a press having a duration of less than 2 seconds, and a press is considered to be “long” when its duration is greater than or equal to 2 seconds.

[0039] When the rolling speed is greater than the threshold speed Vs, the computer 10 orders the actuation of the pivoting of the deflectors 4 into the closed position, as soon as several short presses over a short period are detected, or as soon as several presses having a long duration are detected.

[0040] The several presses correspond to at least two successive presses, when the latter occur within a short period of at most five seconds, or when they include a long press duration (greater than two seconds), this means that the risk of overheating of the braking members is high. Advantageously, the method of the present invention makes it possible to overcome this risk of overheating by effectively identifying the need for cooling of the braking members, while maximizing the autonomy of the motor vehicle 1 thanks to a controlled deployment of the deflectors 4.

[0041] The method for managing the aerodynamic deflector system of the motor vehicle preferably corresponds to a computer algorithm which can be executed in the form of lines of code readable by a computer which can correspond to the computer 10 of [Fig.l].

Claims

Claims

1. Method for managing a system (3) of aerodynamic deflectors (4) mounted on a front bumper (2) and arranged in front of front wheels (6) of a motor vehicle (1), said system (3) comprising two deflectors (4) pivoting between: - an open position of the deflectors (4), in which each of said deflectors (4) projects from the front bumper (2) and arranged opposite the corresponding wheel (6); and - a closed position of the deflectors (4), in which each of said deflectors (4) is longitudinally retracted into the front bumper (2), characterized in that said method ensures management of an actuation of the pivoting of the deflectors (4) as a function of a driving speed of the motor vehicle (1) and as a function of at least one condition of pressing on a brake pedal (12) of said motor vehicle (1).

2. Method according to claim 1, wherein the at least one condition of pressing the brake pedal (12) of the motor vehicle (1) comprising a number and / or a duration of pressing on said brake pedal (12).

3. Method according to one of claims 1 and 2, in which the actuation of the pivoting of the deflectors (4) in the open position of said deflectors (4) is conditioned by: - ​​a driving speed of the motor vehicle (1) greater than a lower limit speed Vi and by the absence of pressure on the brake pedal (12); or - a driving speed greater than a threshold speed Vs and when pressure on the brake pedal (12) comprises a short pressure duration, said threshold speed Vs being at least twice greater than the lower limit speed Vb

4. Method according to one of claims 1 to 3, in which the actuation of the pivoting of the deflectors (4) in the closed position of said deflectors (4) is conditioned by: - ​​a driving speed of the motor vehicle (1) lower than a lower limit speed Vi; or - pressing the brake pedal (12) when the driving speed is between the lower limit speed Vie and a threshold speed Vs at less than twice the said lower limit speed Vb and when detecting the presence of a speed bump on the road; or - at least two successive presses on the brake pedal (12), when the driving speed is higher than the threshold speed Vs.

5. Method according to claim 4, in which the actuation of the pivoting of the deflectors (12) in the closed position of said deflectors (4) is conditioned by a driving speed greater than the threshold speed Vs, and: - when the at least two successive presses on the brake pedal (12) occur over a period less than or equal to five seconds, or - when each press of the at least two successive presses comprises a long press duration.

6. Method according to one of claims 3 to 5, in which the lower limit speed Vi is between 5 km / h and 15 km / h, and the threshold speed Vs is between 40 km / h and 60 km / h.

7. Computer program comprising computer-readable code instructions, characterized in that said program causes the computer to implement the method for managing an aerodynamic deflector system of a motor vehicle (1) according to one of claims 1 to 6, when said program is executed by a computer.

8. A device comprising a computer-readable recording medium, characterized in that the computer program according to claim 7 is recorded on the recording medium.

9. Motor vehicle (1), characterized in that said motor vehicle (1) is configured to execute the method for managing an aerodynamic deflector system (4) of a motor vehicle (1) according to one of claims 1 to 6.

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