EP3134295A1

EP3134295A1 - Method for managing the power supply of display screens on board a motor vehicle

Info

Publication number: EP3134295A1
Application number: EP15718555.4A
Authority: EP
Inventors: Denis D. BLANDIN; Solen KERLEROUX-MAYERE
Original assignee: Renault SAS
Current assignee: Renault SAS
Priority date: 2014-04-22
Filing date: 2015-04-09
Publication date: 2017-03-01
Also published as: US20170043733A1; FR3020024A1; WO2015162353A1; FR3020024B1

Abstract

The invention relates to a method for managing the power supply of display screens (22, 24, 26) on board a motor vehicle, said motor vehicle comprising: an electric battery (28); a vehicle-starting unit (29) that operates only when powered by a voltage no lower than an activation threshold (Sa); a main screen (22) powered by the battery (28); a secondary screen (24, 26) powered by the battery (28); an electronic control unit (30); characterized in that, when the voltage level (U) of the battery (28) is lower than a first predetermined shutoff threshold (S2), at least one secondary screen (26) is turned off by the electronic control unit (30), the first shutoff threshold (S2) being higher than the activation threshold (Sa).

Description

"Method for managing the power supply of onboard display screens on a motor vehicle"

TECHNICAL FIELD OF THE INVENTION

The invention relates to a method for managing the power supply of onboard displays on board a motor vehicle. BACKGROUND ART OF THE INVENTION

The invention relates more particularly to a method for managing the power supply of onboard display screens on board a motor vehicle, the vehicle comprising:

- an onboard electric battery;

- At least one vehicle starting member which is supplied with electricity by the battery, the starting member being functional only when it is supplied with a voltage greater than or equal to an activation threshold;

at least one main screen arranged facing the driver which displays information essential for driving the vehicle, the main screen being powered by the battery;

at least one accessory screen which displays information which is not essential for the driving of the vehicle, the accessory screen being powered by the battery;

an electronic control unit which is capable of determining the battery voltage level at each instant.

Current technology makes digital flat display screens with a very small footprint, especially in thickness. This allows integration large screens in the passenger compartment of the motor vehicle, and in particular in the dashboard.

It is thus known to use such screens to display information important to driving such as the speed, the tank gauge or any other information that was generally displayed via the needle meters. Such a so-called "main" screen is for example arranged behind the steering wheel, in the driver's field of vision.

Accessory screens are also used to perform secondary functions, for example the display of radio stations, a GPS map, the condition of the vehicle air conditioning system. Such a screen often has a touch function that allows the driver or the passenger to control the displayed functions. This screen is usually arranged between the driver's seat and the passenger seat.

Other accessory screens are also arranged facing the passengers. These displays do not perform any function relating to the operation of the vehicle or the vehicle accessory control. They allow the passenger to enjoy various features, such as watching a movie, surfing the internet, checking e-mails, etc.

Nevertheless, these screens are powered by the vehicle battery. However, this energy consumption, if it is not controlled, is likely to discharge the battery to the point of causing a detrimental failure for the use of the vehicle, in particular by no longer allowing enough power to an electric starter of the vehicle.

BRIEF SUMMARY OF THE INVENTION

The present invention proposes a management method of the type described above, characterized in that, when the voltage level of the battery is below a first threshold determined extinction, at least one accessory screen is extinguished by the electronic control unit, the first extinction threshold being greater than the activation threshold.

According to other characteristics of the process:

the vehicle comprises at least a second accessory screen, when the battery voltage level is below a second determined extinction threshold, the second accessory screen is extinguished by the electronic control unit, the second extinction threshold; being between the first determined extinction threshold and the activation threshold;

when the voltage level of the battery is below a determined third extinction threshold, all the screens are extinguished by the electronic control unit;

the third determined extinction threshold is lower than all the other determined extinction thresholds;

when the voltage level of the battery is below a determined darkening threshold, the luminous intensity of the accessory screens is reduced by the electronic control unit, the determined darkening threshold being greater than the extinction thresholds;

when the voltage level of the battery is below the determined threshold of darkening, the luminous intensity of the main screens is reduced by the electronic control unit;

the intensity of at least one screen is reduced in proportion to the drop in the voltage level of the battery from the darkening threshold to the associated extinction threshold;

the brightness of at least one screen is reduced by sectors, the darkened area of each screen being globally proportional to the drop in voltage of the battery from the darkening threshold to the associated extinction threshold. BRIEF DESCRIPTION OF THE FIGURES

Other characteristics and advantages of the invention will appear during the reading of the detailed description which follows for the understanding of which reference will be made to the appended drawings in which:

- Figure 1 is a front view which schematically shows a dashboard of a motor vehicle having display screens;

FIG. 2 is a block diagram showing a method for managing the power supply of the display screens of FIG. 1.

DETAILED DESCRIPTION OF THE FIGURES

In the remainder of the description, elements having an identical structure or similar functions will be designated by the same reference.

In the remainder of the description, longitudinal, vertical and transverse orientations indicated by the "L, V, T" trihedron of FIG. 1 will be adopted without limitation.

FIG. 1 shows the front of a passenger compartment 10 of a rolling motor vehicle. The passenger compartment 10 is crossed by a board 12 of transverse edge.

The cockpit 10 also comprises at least one transverse front row of seats which are arranged longitudinally behind the board 12. The seats are arranged transversely side by side so that their occupants are facing forward, facing the board 12.

In the example shown in Figure 1, the left seat forms a place 14A for seating a driver of the vehicle. The right seat forms a seat 14B for seating a passenger of the vehicle. Facing the driver's seat 14A, the left part of the board 12 has a cockpit 16 which is generally equipped with a steering wheel 18 and a dashboard. The dashboard includes a main display screen 22 which displays information essential to driving the vehicle. For example, the main screen 22 displays the speed of movement of the vehicle, the fuel gauge, or any other information relating to the driving of the vehicle.

Between the two places 14A, 14B before, it is known to arrange various commands of comfort functions of the vehicle, for example the control of the air conditioning, the control of the audio system or a "GPS". In the embodiment shown in Figure 1, these functions are at least partially filled by a first screen 24 viewing accessory. This is for example a 24-touch screen that allows the driver or the passenger to control the various functions listed above. Thus, the first screen 24 accessory displays information that is incidental to the driving of the vehicle, but it is information for controlling certain comfort functions of the vehicle. This screen 24 accessory will therefore be designated later "24 comfort screen".

In front of the passenger seat 14B, the right part of the board 12 has a second display screen 26 which is arranged longitudinally vis-à-vis the passenger seat 14B. The second screen 26 accessory is intended to display information unrelated to the operation of the vehicle. This screen 26 allows the passenger to attend by browsing the internet or watching movies. Thus, the second screen 26 accessory displays information unrelated to the driving of the vehicle or with any function of the vehicle. This screen 26 accessory will be referred to hereafter as "screen 26 of leisure". It is possible to classify these screens 22, 24, 26 according to the importance of the information displayed for the use of the vehicle. Thus, the main screen 22 is the screen is ranked first because it displays the most important information for driving the vehicle. The comfort screen 24 is ranked second because it displays information that allows the use of vehicle accessories or driver assistance applications, such as "GPS". Finally, the screen 26 of leisure is ranked last because it does not broadcast any information related to the vehicle.

The screens 22, 24, 26 for viewing comprise a slab of the "flat screen" type. This is for example a liquid crystal panel, commonly referred to by its acronym "LCD" (Liquid Crystal Display), or a slab electroluminescent, commonly referred to by its acronym "OLED" (Organic Light-Emitting Diode). Since such slabs are widely known, their structure will not be described more precisely later.

Each display screen 22, 24, 26 is integrated in the board 12. Each display screen 22, 24, 26 is here embedded and permanently fixed in a housing provided for this purpose in the board 12 of the vehicle.

Alternatively, the vehicle has other recreational screens, such as screens embedded in the back of the front seats, facing the rear passengers of the vehicle.

In a conventional manner, the vehicle also includes a battery 28 of on-board electric accumulators. This battery 28 is intended to supply different organs of the vehicle, for example headlights, the audio system ...

In the case of a combustion engine vehicle, the battery

28 also serves to supply a vehicle start-up device 29, for example a starter or an alternator-starter. The starting member 29 is able to start the engine of the vehicle only when it is powered by the battery 28 with a voltage "U" electrical greater than or equal to a threshold "Sa" activation. Below this threshold "Sa" of activation, the starting member 29 does not deliver sufficient mechanical power to start the combustion engine.

The battery 28 also powers the main screen 22 and the screens 24, 26 accessories.

The vehicle also has an electronic control unit 30 which is able to determine the voltage level "U" of the battery 28 at any time, by measurement or by estimation.

It has been found that the screens 22, 24, 26 for viewing are likely to consume a lot of electrical energy. In some cases, the consumption of electricity is likely to at least partially discharge the battery 28. However, when the battery 28 has a voltage level "U" below the threshold "Sa" activation of the start member when the engine of the vehicle is cut off, the starting device will not be able to restart the engine. The vehicle is then immobilized.

To solve this problem, the invention proposes a method for managing the power supply of the display screens 22, 24, 26 as a function of the state of charge of the battery 28, and in particular as a function of the voltage level "U determined by the electronic control unit. Such a method is illustrated in FIG.

During a first verification step "E1", the electronic control unit 30 determines whether the voltage level "U" of the battery is below a determined threshold "S1" of darkening. The determined darkening threshold "S1" is greater than the activation threshold "Sa". The darkening threshold "S1" is for example equal to 11.5 V.

If this is not the case, it is estimated that the battery 28 is still sufficiently charged to feed the screens 22, 24, 26 without risk for the power supply of the starter member. The process is thus reiterated from the beginning without any action on the screens 22, 24, 26.

If necessary, before the reiteration, a second step "E2" reset is implemented to turn with their normal brightness level screens 22, 24, 26 whose extinction was forced during a previous iteration of the process.

If this is the case, it means that the voltage level "U" of the battery is below the threshold "S1" of darkening. In this case, the light intensity at least of the screens 22, 24 accessories is reduced by the electronic control unit during a third step "E3" reduction. It is believed that this reduction in intensity should be sufficient to maintain the battery 28 at a voltage level "U" sufficient to activate the start device the next time the vehicle is started.

In the method shown in FIG. 2, the luminous intensity of the main screen 22 is also reduced by the electronic control unit 30 during this third reduction step "E3".

As a variant not shown of the invention, the luminous intensity of the main screen is reduced by the electronic control unit when the voltage level of the battery is lower than a second darkening threshold. This second threshold of darkening being lower than the threshold "S1" of darkening of the accessory screens.

The process then proceeds to a fourth verification step "E4". During this fourth step "E4", the electronic control unit 30 determines whether the voltage level "U" of the battery is lower than a first threshold "S2" determined extinction. The first extinction threshold "S2" is below the darkening threshold "S1" and above the threshold "Sa" of activation. The first threshold "S2" extinction is for example equal to 11, 3 V. If this is not the case, it is estimated that the battery 28 is still sufficiently charged to power the screens 22, 24, 26 without risk for the power supply of the starter member. The process is thus reiterated from the beginning without any other action on the screens 22, 24, 26.

If necessary, before the reiteration, a fifth step "E5" reset is implemented to turn with their reduced level of brightness screens 22, 24, 26 whose extinction was forced during a previous iteration of the process.

If this is the case, it means that the voltage level "U" of the battery is lower than the first threshold "S2" of extinction. In this case, the least important accessory screen 26, that is to say the screen 26 of leisure, is extinguished by the electronic control unit 30 during a sixth "E6" extinction step. It is estimated that this extinction of a screen 26 should be sufficient to maintain the battery 28 at a level of voltage "U" sufficient to activate the organ 29 for starting the next start of the vehicle.

The process then proceeds to a seventh verification step E7 which is initiated by the electronic control unit. During this seventh verification step "E7", the electronic control unit 30 determines whether the voltage level "U" of the battery is below a second determined threshold "S3" of extinction. The second "S3" extinction threshold is lower than the first "S2" extinction threshold, and greater than the "Sa" activation threshold. The second threshold "S3" extinction is for example equal to 11, 1 V.

If this is not the case, it is estimated that the battery 28 is still sufficiently charged to power the screens 22, 24 remaining with a reduced brightness without risk for the supply of the organ 29 start. The process is thus reiterated from the beginning without any other action on the screens 22, 24, 26. If necessary, before the reiteration, an eighth step "E8" of reset is implemented to turn on with their reduced level of brightness the main screen 22 and / or the screen 24 of comfort if their extinction was forced during a previous iteration of the process.

If this is the case, it means that the voltage level "U" of the battery is lower than the second threshold "S3" of extinction. In this case, the second least important accessory screen 24, ie the comfort screen 24, is turned off by the electronic control unit 30 during a ninth extinction step "E9". It is estimated that this extinction of an additional screen 24 should be sufficient to maintain the battery 28 at a level of voltage "U" sufficient to activate the organ 29 start the next start of the vehicle.

The process then proceeds to a tenth verification step "E10" which is initiated by the electronic control unit. During this verification step 10 "E10", the electronic control unit 30 determines whether the voltage level "U" of the battery is lower than a third threshold "S4" determined extinction. The third "S4" extinction threshold is lower than the second "S3" extinction threshold, and greater than the "Sa" activation threshold. Thus, the third threshold "S4" determined extinction is less than all other thresholds "S2, S3" determined extinction The third threshold "S4" extinction is for example equal to 10.9 V.

If this is not the case, it is estimated that the battery 28 is still sufficiently charged to power the main screen 22 with reduced brightness without risk for the supply of the organ 29 start. The process is thus reiterated from the beginning without any other action on the screens 22, 24, 26.

If necessary, before the reiteration, an eleventh step "E11" reset is implemented to light with its level reduces the brightness of the main screen 22 if its extinction has been forced during a previous iteration of the process.

If this is the case, it means that the voltage level "U" of the battery is lower than the third threshold "S4" extinction. In this case, the main screen 22 is in turn turned off by the electronic control unit 30 during a twelfth step "E12" extinguishing. It is believed that the extinction of the main screen 22 is necessary to maintain the battery 28 at a voltage level "U" sufficient to activate the start-up device 29 when the vehicle is next started.

Following this twelfth step "E12", the process is reiterated.

In a non-represented variant of the invention, during the third darkening step "E3", the intensity of at least one of the screens 22, 24, 26 is reduced in proportion to the decrease in the voltage level of the battery since the darkening threshold to the extinction threshold. Thus, the brightness of the entertainment screen 26 will drop faster than the brightness of the main screen 22.

According to another not shown embodiment of the invention, the brightness of at least one screen is reduced by sectors, the darkened area of the screen being generally proportional to the drop in intensity of the battery from the threshold of darkening to the associated extinction threshold. For example, the brightness starts to drop in a banner at the top of the screen, and then, as the battery voltage drops, the width of the strip increases, until it reaches the entire surface of the screen. screen before the screen is turned off by the electronic control unit.

The screen management method 22, 24, 26 made according to the teachings of the invention thus makes it possible to preserve the battery 28 so that the starting member 29 can be sufficiently powered, thus avoiding immobilizing the vehicle.

In addition, the progressiveness of the actions performed on the screens 22, 24, 26 as a function of the voltage level "U" of the battery 28 enables the driver of the vehicle to become aware of a possible problem of charging the battery 28 before the vehicle is immobilized because of the discharge of the battery 28. The driver can thus take measures to recharge or replace the battery 28 preventatively.

Claims

A method for managing the power supply of onboard display screens (22, 24, 26) on board a motor vehicle, the vehicle comprising:

an onboard electric battery (28);

at least one vehicle starting member (29) which is supplied with electricity by the battery (28), the starting member (29) being functional only when it is powered with a voltage greater than or equal to a threshold (Sa) activation;

at least one main screen (22) powered by the battery

(28);

- at least one screen (24, 26) accessory powered by the battery (28);

an electronic control unit (30) which is capable of determining the voltage level (U) of the battery (28) at each instant;

characterized in that, when the voltage level (U) of the battery (28) is less than a first predetermined extinction threshold (S2), at least one accessory screen (26) is extinguished by the unit (30). electronic control, the first threshold (S2) of extinction being greater than the threshold (Sa) activation.

2. Method according to the preceding claim, characterized in that the vehicle comprises at least a second screen (24) accessory, and in that, when the voltage level (U) of the battery is less than a second threshold (S3) determined, the second accessory screen (24) is extinguished by the electronic control unit (30), the second extinction threshold (S3) being between the first determined extinction threshold (S2) and the threshold (Sa) activation.

3. Method according to any one of the preceding claims, characterized in that, when the voltage level (U) of the battery (28) is lower than a third threshold (S4) determined from extinction, all the screens (22, 24, 26) are extinguished by the electronic control unit (30).

4. Method according to the preceding claim taken in combination with any one of the preceding claims, characterized in that the third threshold (S4) determined extinction is less than all other thresholds (S2, S3) determined extinction.

5. Method according to any one of the preceding claims, characterized in that, when the voltage level (U) of the battery (28) is below a threshold (S1) determined darkening, the light intensity of the screens (24, 26) is reduced by the electronic control unit (30), the determined darkening threshold (S1) being greater than the extinction thresholds (S2, S3, S4).

6. Method according to the preceding claim, characterized in that, when the voltage level (U) of the battery (28) is below the determined threshold (S1) of darkening, the luminous intensity of the screens (22) main is reduced by the electronic control unit (30).

7. Process according to any one of claims 5 or

6, characterized in that the intensity of at least one screen (22, 24, 26) is reduced in proportion to the decrease of the voltage level (U) of the battery (28) from the darkening threshold (S1). up to the associated extinction threshold (S2, S3, S4).

8. Method according to any one of claims 5 or 6, characterized in that the brightness of at least one screen (22, 24, 26) is reduced by sectors, the darkened area of each screen (22, 24, 26) being generally proportional to the voltage drop (U) of the battery (28) from the darkening threshold (S1) to the associated extinction threshold (S2, S3, S4).