Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60S—SERVICING, CLEANING, REPAIRING, SUPPORTING, LIFTING, OR MANOEUVRING OF VEHICLES, NOT OTHERWISE PROVIDED FOR
  • B60S1/00—Cleaning of vehicles
  • B60S1/02—Cleaning windscreens, windows or optical devices
  • B60S1/04—Wipers or the like, e.g. scrapers
  • B60S1/06—Wipers or the like, e.g. scrapers characterised by the drive
  • B60S1/08—Wipers or the like, e.g. scrapers characterised by the drive electrically driven
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B60—VEHICLES IN GENERAL
  • B60S—SERVICING, CLEANING, REPAIRING, SUPPORTING, LIFTING, OR MANOEUVRING OF VEHICLES, NOT OTHERWISE PROVIDED FOR
  • B60S1/00—Cleaning of vehicles
  • B60S1/02—Cleaning windscreens, windows or optical devices
  • B60S1/04—Wipers or the like, e.g. scrapers
  • B60S1/32—Wipers or the like, e.g. scrapers characterised by constructional features of wiper blade arms or blades
  • B60S1/38—Wiper blades
  • B60S2001/3844—Wiper blades equipped with means to indicate wear or usage of blade

Definitions

• This disclosure relates to the field of motor vehicle wiper blade systems.
• Wiper blades have the particular function of sweeping a glazed surface of a vehicle in the event of washing of the latter or quite simply to wipe off raindrops in the event of bad weather in order to guarantee good visibility for the user. of the vehicle.
• wiper blade wear detection systems There are wiper blade wear detection systems. When one of them is worn, the vehicle user can be warned via an audible signal or a light signal displayed on the vehicle's dashboard. Having been warned, the user of the vehicle is then aware that he must replace the wiper blade as soon as possible.
• Such a solution has a major defect in that the warning to the user of the vehicle is carried out at the moment when the wiper blade is no longer functional.
• a more or less long period of time may pass where the user drives his vehicle with a worn wiper blade.
• This period of time can be problematic in the event of heavy rain impairing visibility, and thus causing the user of the vehicle to take risks towards himself as well as towards other vehicle users or pedestrians. Furthermore, if the user bases himself on an average lifespan of the wiper blade whose vehicle is equipped to replace it at the end of said average lifespan in order to avoid driving with a used blade, this entails a risk of premature replacement and therefore an economic disadvantage for the user of the vehicle.
• This disclosure improves the situation.
• the subject of the invention is a device for determining a state of wear of a wiper blade for a wiping system intended to be fitted to a motor vehicle, the device for determining a state of wear comprising an angular position sensor configured to measure at least one datum relating to the wiper blade during a sweeping operation and an electronic control unit configured to determine the state of wear of the wiper blade as a function at least one datum measured by the angular position sensor.
• the device according to the present invention makes it possible to estimate in real time the level of wear of the wiper blade and to optimize the replacement thereof. Moreover, as the vehicle is already equipped with the angular position sensor, the device according to the present invention neither complicates nor weighs down the motor vehicle.
• said at least one datum measured by the angular position sensor is an angular position of the wiper blade.
• the electronic control unit is configured to calculate an angular acceleration of the wiper blade from the angular position of the wiper blade.
• the electronic control unit is configured to compare the calculated angular acceleration with at least one parameter representative of a known state of wear.
• the representative parameter of a known state of wear is a profile of evolution of the angular acceleration over a time interval or an average value.
• the electronic control unit is configured to compare the calculated angular acceleration to a plurality of parameters, each parameter being representative of a respective known state of wear.
• the electronic control unit is configured to identify the state of wear of the wiper blade with respect to the known state of wear whose representative parameter is closest to the calculated angular acceleration .
• a method for determining a state of wear of a wiper blade for a wiper system intended to equip a motor vehicle preferably implemented by a device for determining a state of wear. wear as described above, the method for determining a state of wear comprising a step of measuring at least one datum measured by an angular position sensor during a scanning operation.
• said at least one datum measured by the angular position sensor is an angular position of the wiper blade.
• the method comprises a step of calculating an angular acceleration from the angular position of the wiper blade by the electronic control unit.
• the method comprises a step of comparing the calculated angular acceleration with at least one parameter representative of a state of wear known by the electronic control unit.
• the representative parameter of a known state of wear is a profile of evolution of the angular acceleration over a time interval or an average value.
• the method comprises a step of comparing the angular acceleration calculated with a plurality of parameters, each parameter being representative of a respective state of wear known by the electronic control unit.
• the method comprises a step of identifying the state of wear of the wiper blade in the known state of wear, the representative parameter of which is closest to the angular acceleration calculated by the electronic control unit.
• a wiper system for a motor vehicle comprising a device for determining a state of wear as described previously, at least one wiper blade, a drive arm of said at least one wiper blade wiper and a drive motor for the drive arm, the angular position sensor of the device for determining a state of wear being mounted on a shaft of the drive motor.
• a computer program comprising instructions for the implementation of all or part of a method as defined herein when this program is executed by a processor.
• a non-transitory, computer-readable recording medium on which such a program is recorded.
• FIG. 1 is a schematic view of a system for wiping a vehicle windshield comprising a device for determining a state of wear of a wiper blade according to the present invention.
• FIG. 1 shows a flowchart of a method for determining a state of wear of a wiper blade according to the present invention, implemented by the device for determining a state of wear of the .
• a system 10 for wiping a window 12 of a motor vehicle which here is a windshield of the vehicle.
• the wiper system 10 here comprises two wiper blades 14. Each wiper blade 14 is carried by a brush holder 16 also commonly called wiper arm or drive arm.
• each wiper blade 14 comprises at least one wiper blade which is a flexible blade made of natural or synthetic elastomeric material, including a lower edge of longitudinal orientation in the general longitudinal direction of the wiper blade 14, cooperates with the outer surface of the windshield 12 to ensure cleaning and / or wiping.
• the working edge of the wiper blade is also called the wiper blade lip.
• a proximal end 18 of each brush holder 16 is connected to a drive motor 20, while a distal end 22 of each brush holder 16 is connected to the wiper blade 14 which it carries.
• Each drive motor 20 is designed to drive the brush holder 16 in scanning in an alternating pivoting movement, or cyclic rotational movement, according to a portion of an arc of a circle, around a pivoting or rotation axis whose the general orientation is generally orthogonal to the general longitudinal orientation of the brush holder 16.
• each drive motor 20 comprises an output shaft, not shown, which transmits to the associated brush holder 16, a drive torque, directly or for example via a linkage.
• Each drive motor 20 is for example an electric motor and the drive motors 20 are connected to a source 24 of electric power, such as for example a storage battery of the vehicle, or an alternator.
• a source 24 of electric power such as for example a storage battery of the vehicle, or an alternator.
• Each drive motor 20 is connected to the source 24 of electrical power by a unit 26 for piloting and controlling the wiper system 10, otherwise called an electronic control unit.
• the piloting and control unit 26 is in particular designed and configured to manage the operation of the wiper system 10 according to several predefined programs of use, for example by controlling the rotational drive speed of the brush holders 16 by regulation of the current supplied to the drive motors 20, for a given value of the supply voltage of the drive motors 20 supplied by the electric power source 24.
• the wiper system 10 also includes a rain sensor 28 which is connected to the piloting and control unit 26.
• the wiping system 10 again comprises here a device 30 for cleaning the outer surface of the windshield, which comprises a pump 32 which is connected to the piloting and control unit 26 and to the electrical power source 24, and which is designed to take windscreen washer fluid 34 from a reservoir 36 to convey it to means for spraying the liquid onto the outer surface of the windshield 12, these spraying means being for example nozzles 38 arranged on the bonnet of the motor vehicle or else carried by the wiper blades 14 or else by the brush holders 16.
• each wiper blade holder 16 is capable of occupying a so-called service position or sweeping use position, in which the wiping edge of the wiper blade of the windscreen wiper blade is in contact with the outer surface of the wiped glass, in particular the windscreen.
• each brush holder 16 In the service position of each brush holder 16, they can be driven in alternate cyclic scanning by the drive motors 20.
• the wiper blade and the associated wiper blades are in their so-called service position or in a storage position, called parking position.
• the wiper system 10 also includes an angular position sensor 40 in the drive motor 20.
• the angular position sensor 40 is configured to measure the angular position of the wiper blade in real time during the wiping operation.
• the letter P illustrates the position of the wiper blades 14 – brush holder 16 assembly.
• the angular position sensor 40 makes it possible in particular to stop each wiper blade 14 and associated wiper blade holder 16 in the parking position when the wiper system is stopped.
• the blades gradually wear out, particularly under the effect of various environmental constraints such as solar radiation and outside temperature.
• the piloting and control unit 26 is configured to determine the state of wear of the wiper blade according to at least one datum measured by the angular position sensor.
• said at least one datum measured by the angular position sensor is an angular position of the wiper blade.
• the piloting and control unit 26 is configured to calculate an angular acceleration of the wiper blade from the angular position of the wiper blade, as will be detailed later.
• the angular position sensor 40 and the piloting and control unit 26 form a device 42 for determining the state of wear of the wiper blades 14.
• the invention also relates to a method 100 for determining the state of wear of the wiper blades 14, preferably implemented by the device 42 for determining the state of wear of the wiper blades 14 .
• the method 100 comprises a step 102 of measurement (MES) of at least one datum M measured by the angular position sensor 40 during the scanning operation.
• said at least one datum measured by the angular position sensor is the angular position of the wiper blade.
• the measured data M is equal to the angular position P.
• the method 100 comprises a step 104 of calculating (CAL) an angular acceleration, denoted A, from the angular position P.
• the angular acceleration A is the second time derivative of the angular position P.
• the angular acceleration A is also the first time derivative of an angular velocity V, itself the first time derivative of the angular position P.
• FIGS. 3 to 5 illustrate respective curves 44, 46 and 48 of change over time t, over a period of less than 2 seconds, of the angular position P of the wiper blade , the angular velocity V and the angular acceleration A.
• the method 100 also includes a step 106 of comparison (COMP) of the calculated angular acceleration A with at least one parameter representative of a state of wear known by the electronic control unit.
• COMP comparison
• the representative parameter is an average value, Avg.
• the method 100 then advantageously comprises a step 108 of alerting (ALE) the user, for example in the form of triggering a light and/or sound signal from the dashboard of the motor vehicle.
• ALE alerting
• the parameter representative of a known state of wear is a profile, called reference profile, of evolution of the angular acceleration over a time interval, for example over a rotary cycle or over a defined number of rotary cycles, for example five rotary cycles.
• the state of wear is considered as new.
• the difference, in absolute value, between A and Moy becomes greater than the predefined threshold, then the state of wear is considered old.
• the deviation can be calculated for each position measurement P, which corresponds for example to about fifty calculations of deviations.
• the method 100 then advantageously comprises a step 108 of alerting (ALE) the user, for example in the form of triggering a light and/or sound signal from the dashboard of the motor vehicle.
• ALE alerting
• each calculated acceleration A is compared with a plurality of parameters, each parameter being representative of a respective state of wear known by the electronic control unit. For example, you can predefine three levels of wear: new, medium and old.
• each calculated acceleration A is compared with each representative parameter of each level of wear and each of the differences, En, Em and Ev, is calculated between the value A and the respective representative parameter of the new level of wear, average and old.
• the state of wear is attributed to the lowest deviation among the deviations En, Em and Ev.
• the method 100 then advantageously comprises a step 108 of alerting (ALE) the user, for example in the form of triggering a light and/or sound signal from the dashboard of the motor vehicle.
• ALE alerting
• each representative parameter can be a reference profile as introduced in relation to the second variant, and associated with the respective level of wear new, average, old.
• the deviations En, Em and Ev are then advantageously calculated for each position measurement P, which corresponds for example to about fifty calculations of deviations.
• the device 42 for determining the state of wear of the wiper blades 14 and to the method 100 for determining the state of wear of the wiper blades 14 according to the present invention it is possible to estimate in real time the state of wear of the wiper blade 14, using only the angular position sensor 40 and the unit 26 for controlling and controlling the wiper system 10, without it being necessary to add sensors dedicated to determining the state of wear of the wiper blade 14.

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• Engineering & Computer Science (AREA)
• Mechanical Engineering (AREA)
• Length Measuring Devices With Unspecified Measuring Means (AREA)
• Control Of Electric Motors In General (AREA)

Applications Claiming Priority (2)

Publications (1)

Family

ID=77411876

Family Applications (1)

Country Status (4)

Family Cites Families (3)

• 2021
  • 2021-06-30 FR FR2107096A patent/FR3124857B1/fr active Active
• 2022
  • 2022-06-30 WO PCT/EP2022/068090 patent/WO2023275265A1/fr active Application Filing
  • 2022-06-30 CN CN202280045633.7A patent/CN117561185A/zh active Pending
  • 2022-06-30 EP EP22735918.9A patent/EP4363279A1/de active Pending

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