Monitoring the current to a motor involved in the immobilization of a vehicle

Abstract

A monitoring method is implemented in a vehicle comprising a drivetrain comprising a brake device comprising a toothed wheel and a brake finger suitable for being placed by a motor, powered by a measurable current, in an immobilization position or a decoupled position. This method comprises a step (10-50) in which, in the event of authorization of a placement of the brake finger in its immobilization or uncoupled position, requested by a user, the operation of the motor is prohibited when this measured current is comprised between first and second thresholds chosen as a function of this requested position for at least a first chosen duration and associated with this first threshold.

Description

DESCRIPTION TITLE: MONITORING THE CURRENT SUPPLYING A MOTOR INVOLVED IN IMMOBILIZING A VEHICLE The present invention claims priority from French application No. 2210339 filed on 10.10.2022, the content of which (text, drawings and claims) is incorporated herein by reference. Technical field of the invention

[0001] The invention relates to vehicles comprising a transmission chain comprising a brake finger device moved by a motor, and more precisely to the monitoring within such vehicles of the current supplying this motor. State of the art

[0002] Some vehicles, possibly of the automobile type, include a drive chain that includes a brake device (or "parking brake") comprising a wheel, equipped with teeth, and a brake finger moved by an electric motor. Generally, the toothed wheel is coupled to the shaft line of an automated gearbox or to a reducer.

[0003] The brake (or "park") finger is capable of being placed by the associated (electric) motor, on the order of a computer associated with the brake device, in an immobilization position, in which it is housed between two teeth of the toothed wheel to immobilize the vehicle, or in a decoupled position, in which it is decoupled from the wheel and therefore allows the vehicle to move. The engagement of the brake finger between two teeth of the toothed wheel may, for example, result from an action by the driver of the vehicle on a control member (for example, by placing the gear lever in its parking position). Similarly, the disengagement of the brake finger from these teeth may, for example, result from an action by the driver of the vehicle on this control unit (for example by removing the gear lever from its parking position).

[0004] Currently, and as described in particular in patent document CN-A 114001157, once the computer associated with the brake device has authorized a placement of the brake finger in its immobilized position or its decoupled position, requested by a user of the vehicle, it monitors the measured current which supplies the motor associated with the brake finger so that it is not damaged by an overcurrent, for example caused by a blocking of the brake finger. To this end, the computer compares the measured current to a predefined threshold, and if this measured current is higher than this threshold, it immediately prohibits the operation of the motor (by interrupting its current supply), which interrupts the placement of the brake finger requested by the user.

[0005] A main disadvantage of this operating mode is that it can cause a reduction in the availability of the vehicle immobilization function by means of the brake device. Indeed, the motor may, for example, momentarily require a current peak when the brake finger encounters a tooth of the gear wheel instead of being housed in a hollow of the latter (located between two teeth). However, if this peak exceeds the predefined threshold, the operation of the motor is immediately stopped while there is no danger for the brake device, which makes it impossible, in particular, to recharge a vehicle battery if the brake finger cannot be placed in its immobilization position, or to start the vehicle if the brake finger cannot be placed in its decoupled position.

[0006] The invention therefore aims in particular to improve the situation. Presentation of the invention

[0007] For this purpose, it proposes in particular a monitoring method intended to be implemented in a vehicle comprising a chain transmission comprising a brake device comprising a wheel provided with teeth and a brake finger suitable for being placed by a motor, supplied by a measurable current, in an immobilization position, in which it is housed between two teeth to immobilize the vehicle, or a decoupled position, in which it is decoupled from this wheel.

[0008] This monitoring method is characterized by the fact that it comprises a step in which, in the event of authorization of a placement of the brake finger in its immobilized or decoupled position, requested by a user, the operation of the motor is prohibited when the measured current is between first and second thresholds which are chosen as a function of this requested position for at least a first duration which is chosen and associated with this first threshold.

[0009] Thus, when certain conditions are met, the motor is allowed to consume a current peak, which makes it possible to avoid stopping it unnecessarily when there is no real danger for the brake device, and therefore to carry out the movement of the brake finger requested by the user.

[0010] The monitoring method according to the invention may include other characteristics which may be taken separately or in combination, and in particular:

[0011] - in its step, in the event of authorization of a placement of the brake finger in its immobilization or decoupled position, requested by the user, the operation of the motor is prohibited when the measured current exceeds the second threshold chosen according to the requested position for at least a second duration chosen associated with this second threshold and strictly less than the first duration associated with the first threshold;

[0012] - in the presence of the first option, in its step, the second duration associated with the immobilization position can be between 30 ms and 50 ms, and the second duration associated with the decoupled position can be between 30 ms and 50 ms;

[0013] - in its step, in the event of authorization of a placement of the brake finger in its immobilization or decoupled position, requested by the user, the operation of the motor can be authorized when the measured current is lower than a third threshold chosen according to this requested position and lower than or equal to the first threshold associated with this requested position, whatever the duration;

[0014] - in its step, the first threshold associated with the immobilization position can be between 45 A and 55 A, the first threshold associated with the decoupled position can be between 40 A and 50 A, the first duration associated with the immobilization position can be between 40 ms and 60 ms, and the first duration associated with the decoupled position can be between 40 ms and 60 ms;

[0015] - in its step, the second threshold associated with the immobilization position can be between 50 A and 60 A, and the first threshold associated with the decoupled position can be between 45 A and 55 A;

[0016] - in its step, in the event of a prohibition on engine operation, at least one additional action can be carried out in the vehicle, chosen from a recording of at least one fault code representative of an overcurrent situation at the engine level, and a triggering of an alert generation for the user signaling a problem in the transmission chain.

[0017] The invention also provides a computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing a monitoring method of the type presented above, in a vehicle comprising a transmission chain comprising a brake device comprising a wheel provided with teeth and a brake finger capable of being placed by a motor, supplied by a measurable current, in an immobilization position, in which it is housed between two teeth to immobilize the vehicle, or a decoupled position, in which it is decoupled from that wheel, to monitor this measured current.

[0018] The invention also proposes a monitoring device intended to equip a vehicle comprising a transmission chain comprising a brake device comprising a wheel provided with teeth and a brake finger suitable for being placed by a motor, supplied by a measurable current, in an immobilization position, in which it is housed between two teeth to immobilize the vehicle, or a decoupled position, in which it is decoupled from this wheel.

[0019] This monitoring device is characterized by the fact that it comprises at least one processor and at least one memory arranged to carry out the operations consisting, in the event of authorization of a placement of the brake finger in its immobilized or decoupled position, requested by a user, in triggering a prohibition of operation of the motor when the measured current is between first and second thresholds which are chosen as a function of the requested position for at least a first duration which is chosen and associated with this first threshold.

[0020] The invention also proposes a vehicle, possibly of the automobile type, and comprising, on the one hand, a transmission chain comprising a brake device comprising a wheel provided with teeth and a brake finger suitable for being placed by a motor, supplied by a measurable current, in an immobilization position, in which it is housed between two teeth to immobilize the vehicle, or a decoupled position, in which it is decoupled from this wheel, and, on the other hand, a monitoring device of the type presented above. Brief description of the figures

[0021] Other characteristics and advantages of the invention will appear on examining the detailed description below, and the appended drawings, in which:

[0022] [Fig. 1] schematically and functionally illustrates an exemplary embodiment of a vehicle comprising a GMP transmission chain with an electric motor powered by a rechargeable main battery and coupled to a reducer associated with an electric motor brake device, and a monitoring device according to the invention,

[0023] [Fig. 2] schematically and functionally illustrates an exemplary embodiment of a brake device calculator comprising an exemplary embodiment of a monitoring device according to the invention, and

[0024] [Fig. 3] schematically illustrates an example of an algorithm implementing a monitoring method according to the invention. Detailed description of the invention

[0025] The invention aims in particular to propose a monitoring method, and an associated monitoring device DS, intended to enable monitoring of the measured current cm which supplies an electric motor MF responsible for moving a brake finger DF2 of a brake device (or parking brake) DF1 of a transmission chain of a vehicle V.

[0026] In the following, it is considered, by way of non-limiting example, that the vehicle V is of the automobile type. It is for example a car, as illustrated in figure 1. But the invention is not limited to this type of vehicle. It concerns in fact any type of vehicle comprising a transmission chain with a braking device (or parking brake) with an electric motor. Thus, it concerns, for example, land vehicles (utility vehicles, camper vans, minibuses, coaches, trucks, motorcycles, road machinery, construction machinery, machinery agricultural, recreational machinery (snowmobile, kart), and tracked vehicles, for example), boats and aircraft.

[0027] Furthermore, it is considered in the following, by way of non-limiting example, that the vehicle V comprises a transmission chain with a powertrain (or GMP) of the all-electric type (and therefore whose drive is provided exclusively by at least one electric motor MME). But the GMP could be of the hybrid type (thermal and electric) or purely thermal.

[0028] Furthermore, it is considered in the following, by way of non-limiting example, that the electric motor MME is supplied with electrical energy by a main (or traction) battery BP, rechargeable during recharging phases. But the electric motor MME could be supplied with electrical energy by a fuel cell.

[0029] Figure 1 schematically shows a vehicle V comprising a transmission chain with a brake device (or parking brake) DF1 and an electric GMP (and therefore an electric motor MME), a supervision computer CS, an on-board network RB, a service battery BS, a main (or traction) battery BP, a converter CV, and a monitoring device DS according to the invention.

[0030] The on-board network RB is an electrical power supply network to which electrical (or electronic) equipment (or components) that consume electrical energy are coupled.

[0031] The service battery BS is responsible for supplying electrical energy to the on-board network RB, in addition, here, to that supplied by the CV converter powered by the main battery BP, and sometimes instead, here, of this CV converter. For example, this service battery BS can be arranged in the form of a very low voltage battery (typically 12 V, 24 V or 48 V). It is rechargeable at least by the (current) converter CV. In the following, it is considered, by way of non-limiting example, that the BS service battery is of the 12 V Lithium-ion type.

[0032] The transmission chain has a GMP which is, here, purely electric and therefore which comprises, in particular, an electric motor MME, a motor shaft AM, and a transmission shaft AT. Here, the term "electric motor" means an electric machine arranged so as to provide an output torque, defined by a torque setpoint, to move the vehicle V when it is supplied with electrical energy (here) by the main battery BP, as well as possibly to recover torque, for example in a regenerative braking phase.

[0033] The operation of the transmission chain (and therefore of the GMP) is supervised by the CS supervision computer.

[0034] The electric motor MME (here an electric motor) is coupled to the main battery BP, in order to be supplied with electrical energy, as well as possibly to supply this main battery BP with electrical energy, for example in a regenerative braking phase.

[0035] It is considered in the following, by way of non-limiting example, that the electric motor MME comprises a rotor and a stator.

[0036] Furthermore, this electric motor MME is coupled to the motor shaft AM, to provide it with the output torque by rotational drive. This motor shaft AM is here coupled to a reducer RDC which is also coupled to the transmission shaft AT, itself coupled to a first train T1 (here of wheels), preferably via a differential DV. The operation of the electric motor MME is controlled by a machine computer CM, and supervised by the supervision computer CS.

[0037] It should also be noted that the first train T1 is here located in the front part PW of the vehicle V. But in a variant this first train T1 could be the one which is referenced here T2 and which is located in the rear PRV part of vehicle V.

[0038] The CV converter is also responsible, here, during the driving phases of the vehicle V, for converting part of the electrical current stored in the main battery BP to supply converted electrical current to the on-board network RB and the service battery BS (to recharge it).

[0039] It will be noted, as illustrated non-limitingly in figure 1, that the CV converter can be part of a CH charger also comprising a recharge calculator (not illustrated) responsible, at least, for controlling the recharges of the main battery BP.

[0040] The main (or traction) battery BP may, for example, include electrical energy storage cells, possibly electrochemical (for example, lithium-ion (or Li-ion) or Ni-Mh or Ni-Cd type). Also, for example, the main battery BP may be of the low voltage type (typically 450 V for illustration purposes). But it could be of the medium voltage or high voltage type.

[0041] It should also be noted that the main BP battery is associated with a BB battery box which includes a CB battery calculator. This main BP battery and its BB battery box constitute a battery pack.

[0042] It will also be noted that in the example illustrated non-limitingly in Figure 1, the vehicle V also comprises a distribution box BD to which the service battery BS, the converter CV and the on-board network RB are coupled. This distribution box BD is responsible for distributing in the on-board network RB the electrical energy stored in the service battery BS or produced by the converter CV, for the supply of the electrical components (or equipment) coupled to the on-board network RB according to power supply requests received (in particular from the supervision computer CS of the GMP).

[0043] The DF1 brake device (or parking brake) includes an RD wheel with teeth, a DF2 brake finger, an MF electric motor, and a first CF calculator.

[0044] The RD gear wheel is here coupled to the RDC reducer. However, when the transmission chain includes an automated gearbox, the RD gear wheel can be coupled to the shaft line of this gearbox, for example.

[0045] The brake (or parking) finger DF2 is suitable for being placed by the (electric) motor MF, on the order of the first computer CF, in an immobilization position, in which it is housed between two teeth of the toothed wheel RD (and therefore engaged) to immobilize the vehicle V, or in a decoupled position, in which it is decoupled from the toothed wheel RD (and therefore disengaged) and therefore allows the vehicle V to move. It will be understood that the operation of the motor MF is controlled by the first computer CF and that this operation (intended to move the brake finger DF2) requires that this motor MF consumes an (electric) current whose value cm is measured by a first sensor C1 and can vary depending on the force transmitted to it by the brake finger DF2 during its contacts with the toothed wheel RD.

[0046] Each measured current cm can, for example, be transmitted periodically to the first CF calculator via a vehicle communication network V (possibly multiplexed).

[0047] In the example illustrated non-limitingly in Figure 1, the engagement of the brake finger DF2 between two teeth of the toothed wheel RD results from an action of the driver of the vehicle V on the gear lever LV (and more precisely on the placement of this gear lever LV in its parking position). Similarly, the disengagement of the brake finger DF2 from these teeth results from an action of the driver of the vehicle V on the gear lever LV (and more precisely from the removal of this gear lever LV from its parking position).

[0048] In fact, when the driver places the gear lever LV in its parking position, a second computer of the vehicle V transmits a request to engage the brake finger DF2 to the first computer CF, so that it causes the brake finger DF2 to be placed in its immobilized position. Similarly, when the driver removes the gear lever LV from its parking position, this second computer transmits a request to disengage the brake finger DF2 to the first computer CF, so that it causes the brake finger DF2 to be placed in its decoupled position. It will be noted that in the example illustrated non-limitingly in Figure 1, the second computer is the supervision computer CS, but this is not obligatory (it could for example be a dedicated computer).

[0049] It will also be noted that in a variant embodiment not illustrated, the driver's actions relating to the brake device DF1 could be carried out by means of a control member of the vehicle V other than the gear lever LV.

[0050] When the driver of vehicle V requests the engagement of brake finger DF2 (or its placement in the immobilization position), the first computer CF authorizes this engagement (or this placement) if the last measurement mv of the speed of vehicle V, which it has received, is strictly lower than a chosen threshold sv. For example, this threshold sv can be between +3 km / h and +10 km / h.

[0051] Also for example, it is a DCT trajectory control device of the ESP / ABS type of the vehicle V which can be responsible for periodically measuring (or estimating) the current speed mv of the latter (V), for example from information provided by a second sensor C2 which is associated with one of the wheels of the vehicle V. This second sensor C2 can be coupled to a wheel hub and can constitute an angular encoder determining a number of teeth passing in front of it per second. In this case, the computer of the DCT trajectory control device can determine the distance traveled as a function of the number of teeth indicated by the second sensor C2 and the wheel development, then measure (or estimate) the current speed (which then constitutes a measurement (or estimate) of speed mv) by integrating this distance traveled over time.

[0052] But the mv speed measurements (or estimates) could have another origin than the DCT trajectory control device calculator.

[0053] As mentioned above, the invention proposes in particular a monitoring method intended to enable monitoring of the measured current cm which is supplied by the first sensor C1 and which represents the current consumed by the motor MF.

[0054] This (monitoring) method can be implemented at least partially by the monitoring device DS (illustrated at least partially in Figures 1 and 2) which comprises for this purpose at least one processor PR1, for example a digital signal processor (or DSP ("Digital Signal Processor")), and at least one memory MD. This monitoring device DS can therefore be implemented in the form of a combination of electrical or electronic circuits or components (or "hardware") and software modules (or "software"). For example, it can be a microcontroller.

[0055] The MD memory is RAM in order to store instructions for the implementation by the processor PR1 of at least part of the monitoring method. The processor PR1 may comprise integrated (or printed) circuits, or several integrated (or printed) circuits connected by wired or wireless connections. An integrated (or printed) circuit is understood to mean any type of device capable of carrying out at least one electrical or electronic operation.

[0056] In the example illustrated non-limitingly in Figures 1 and 2, the monitoring device DS is part of the first computer CF. But this is not obligatory. Indeed, the monitoring device DS could include its own dedicated computer, which is then coupled to the first computer CF.

[0057] As illustrated non-limitingly in Figure 3, the (monitoring) method, according to the invention, comprises a step 10-50 which is implemented when the GMP of the vehicle V is in operation and that in a sub-step 10 the first computer CF has authorized a placement of the brake finger DF2 in its immobilization position or its decoupled position, requested by a user of the vehicle V (here by an action on the gear lever LV). This authorization is given when the last speed measurement mv received is lower than the threshold sv, and triggers, on order of the first computer CF, the starting of the engine MF (by its power supply via the on-board network RB).

[0058] Step 10-50 of the method comprises a sub-step 40 in which, in the presence of the aforementioned placement authorization, the (monitoring device DS triggers a prohibition of) operation of the motor MF is prohibited when the measured current is between first s1 j and second s2 j thresholds, which are chosen as a function of the position (immobilized or decoupled) requested by the user, for at least a first duration d1 j which is chosen and associated with this first threshold s1 j.

[0059] Here, the index j can take two values, for example equal to 1 when the requested position is the immobilization (or engaged) position and to 2 when the requested position is the decoupled (or disengaged) position. Consequently, in the case of authorization to place the brake finger DF2 in its immobilization position, the first threshold s11 and the first duration d11 are used, and in the case of authorization to place the brake finger DF2 in its decoupled position, the first threshold sl2 and the first duration dl2 are used.

[0060] Thanks to the invention, when the MF motor momentarily needs a current peak during an authorized movement of the brake finger DF2, it is authorized to consume this current peak provided that it is not too high and that it does not last long. This avoids unnecessarily stopping the operation of the MF motor while that there is no real danger for the brake device DF1. It is therefore possible, in many cases, to complete the movement of the brake finger DF2, thus making it possible, for example, to recharge the main battery BP of the vehicle V once the brake finger DF2 is placed in its immobilized position, or to start the vehicle V once the brake finger DF2 is placed in its decoupled position, without risk of damage to the engine MF.

[0061] For example, in step 10-50 the first threshold s11 associated with the immobilization position can be between 45 A and 55 A. As an illustrative example, this first threshold s11 can be equal to 50 A. But other values ​​of the first threshold s11 can be used. For example, the first threshold s11 can be chosen during the development phase of the vehicle V.

[0062] Also for example, in step 10-50 the first threshold s12 associated with the decoupled position can be between 40 A and 50 A. As an illustrative example, this first threshold SI2 can be equal to 45 A. But other values ​​of the first threshold SI2 can be used. For example, the first threshold SI2 can be chosen during the development phase of the vehicle V.

[0063] Also for example, in step 10-50 the first duration d11 associated with the immobilization position can be between 40 ms and 60 ms. As an illustrative example, this first duration d11 can be equal to 50 ms. But other values ​​of the first duration d11 can be used. For example, the first duration d11 can be chosen during the development phase of the vehicle V.

[0064] Also for example, in step 10-50 the first duration dl2 associated with the decoupled position can be between 40 ms and 60 ms. As an illustrative example, this first duration dl2 can be equal to 50 ms. But other values ​​of the first duration dl2 can be used. For example, the first duration dl2 can be chosen during the development phase of the vehicle V.

[0065] Also for example, in step 10-50 the second threshold s2i associated with the immobilization position can be between 50 A and 60 A. As an illustrative example, this second threshold s2i can be equal to 55 A. But other values ​​of the second threshold s2i can be used. For example, the second threshold s2i can be chosen during the development phase of the vehicle V.

[0066] Also for example, in step 10-50 the second threshold S22 associated with the decoupled position can be between 45 A and 55 A. As an illustrative example, this second threshold s22 can be equal to 50 A. But other values ​​of the second threshold s22 can be used. For example, the second threshold s22 can be chosen during the development phase of the vehicle V.

[0067] It will be noted that in sub-step 40 of step 10-50, in the event of authorization of a placement of the brake finger DF2 in its immobilized or decoupled position, it is possible to prohibit the (the monitoring device DS can trigger the prohibition of the) operation of the motor MF when the measured current cm exceeds the second threshold s2j, which is chosen as a function of this requested position (and strictly greater than the first threshold s1j associated with this requested position), for at least a second duration d2j associated with this second threshold s2j and strictly less than the first duration d1j associated with this first threshold s1j.

[0068] In the presence of this option, in the event of authorization to place the brake finger DF2 in its immobilized position, the first threshold s11 associated with the first duration d1 i and the second threshold s2i associated with the second duration d2i are used, and in the event of authorization to place the brake finger DF2 in its decoupled position, the first threshold s12 associated with the first duration d12 and the second threshold s22 associated with the second duration d22 are used.

[0069] This option allows two tolerances for a current peak consumed by the MF motor. The first tolerance allows a current peak to be between the first threshold s11 and second threshold s2i for a duration that is less than or equal to the first duration d11. The second tolerance allows a current peak greater than the second threshold s2i for a duration that is less than or equal to the second duration d22 which is strictly less than the first duration d11. In other words, the higher the measured current cm, the less it can last.

[0070] Also for example, in step 10-50 the second duration d2i associated with the immobilization position can be between 30 ms and 50 ms. As an illustrative example, this second duration d2i can be equal to 40 ms. But other values ​​of the second duration d2i can be used. For example, the second duration d2i can be chosen during the development phase of the vehicle V.

[0071] Also for example, in step 10-50 the second duration d22 associated with the decoupled position can be between 30 ms and 50 ms. As an illustrative example, this second duration d22 can be equal to 40 ms. But other values ​​of the second duration d22 can be used. For example, the second duration d22 can be chosen during the development phase of the vehicle V.

[0072] In order to determine the duration during which the measured current cm exceeds a threshold s1 j or s2 j, one (the monitoring device DS) can trigger a time delay which is equal to the first duration d1 j or to the second duration d2 j as soon as the measured current cm becomes greater than the first threshold s1 j and less than the second threshold s2 j or greater than the second threshold s2 j for a first time. When this first d1 j or second d2 j duration expires (and the threshold s1 j or s2 j concerned is still exceeded), in substep 40 one (the monitoring device DS) decides to prohibit the operation of the motor MF.

[0073] For example, and as illustrated non-limitingly in Figure 3, step 10-50 may comprise a sub-step 20 in which, after a placement authorization, one (the monitoring device DS) may compare the measured current cm to the thresholds s1 j and s2 j. If the measured current cm is lower than the first threshold s1j, we (the monitoring device DS) return to perform sub-step 20. On the other hand, if the measured current cm is higher than the first threshold s1j and lower than the second threshold s2j, we (the monitoring device DS) can trigger the time delay of the first duration d1j, or if the measured current cm is higher than the second threshold s2j, we (the monitoring device DS) can trigger the time delay of the second duration d2j in this sub-step 20. Then, in a sub-step 30 of step 10-50, we determine whether the triggered time delay has expired. If not, we (the monitoring device DS) return to perform sub-step 20 to continue performing the threshold comparison, a priori without triggering a new time delay since this has already been done. If so (expiration), we (the monitoring device DS) perform sub-step 40 to prohibit the use of the MF engine.

[0074] It will be noted that in step 10-50 (and for example in sub-step 20), in the event of authorization of a placement of the brake finger DF2 in its immobilized or decoupled position, one (the monitoring device DS) can authorize the operation of the motor MF when the measured current cm is less than a third threshold s3j which is chosen according to this requested position and less than or equal to the first threshold s1 j which is associated with this requested position, whatever the duration. In other words, as soon as the measured current cm is less than the third threshold s3j, the duration is not taken into account because it is considered that there is no overcurrent situation.

[0075] In the presence of the last option, if the third threshold s3j is equal to the first threshold s1 j, we find ourselves in the situation described above for sub-step 20 (we (the monitoring device DS) return to perform sub-step 20 if the measured current cm is lower than the third threshold s3j). On the other hand, if the third threshold s3j is lower than the first threshold s1 j, we must also compare the current measured cm at the third threshold s3j concerned in sub-step 20 and we associate a third duration d3j with this third threshold s3j.

[0076] It will be noted that in step 10-50 (and for example in sub-step 40), in the event of a prohibition on operation of the MF engine, it is also possible to carry out (the monitoring device DS can also trigger the carrying out) in the vehicle V at least one complementary action chosen from:

[0077] - the recording of at least one fault code representative of an overcurrent situation at the MF motor level, and

[0078] - triggering an alert generation for the user of vehicle V signaling a problem in the transmission chain.

[0079] The recording of at least one fault code representative of an overcurrent situation at the motor MF is intended to facilitate the search for the origin of such an overcurrent situation by a technician of an after-sales service, and to allow this technician to solve the problem and to inform the user of the vehicle V of the origin of the prohibition of operation of the brake device DF1. For example, the supervision computer CS and / or the first computer CF can store this fault code.

[0080] The user may be alerted, for example, by means of an illuminated indicator light (for example in the dashboard of the vehicle V) and / or a message displayed on at least one screen of the vehicle V (for example on the dashboard or a central instrument panel) or on the screen of a smartphone of the user, and / or broadcast by at least one loudspeaker of the vehicle V or of this smartphone. The aforementioned indicator light may, for example, be a service indicator light, but it could also be a indicator light dedicated to the DF1 brake device. This alert is intended to suggest to the user to bring the vehicle V to an after-sales service to have it checked.

[0081] It will also be noted, as illustrated non-limitingly in Figure 3, that step 10-50 may also comprise a sub-step 50 in which one (the monitoring device DS) may re-authorize the operation of the MF engine. In this case, re-authorization may preferably be given after waking up the vehicle V after it has fallen asleep, and possibly when upon waking up there is no longer any threshold exceedance for a fourth chosen duration d4j.

[0082] For example, in sub-step 50 of step 10-50, the fourth duration d4i associated with the immobilization position may be between 40 ms and 60 ms. As an illustrative example, this fourth duration d4i may be equal to 50 ms. But other values ​​of the fourth duration d4i may be used. For example, the fourth duration d4i may be chosen during the development phase of the vehicle V.

[0083] Also for example, in sub-step 50 of step 10-50, the fourth duration d42 associated with the immobilization position may be between 40 ms and 60 ms. As an illustrative example, this fourth duration d42 may be equal to 50 ms. But other values ​​of the fourth duration d42 may be used. For example, the fourth duration d42 may be chosen during the development phase of the vehicle V.

[0084] Preferably, during a re-authorization of the operation of the MF engine, in sub-step 50, the generation of an alert for the user is also stopped (the monitoring device DS stops triggering the generation of an alert), when this additional action is planned.

[0085] In an alternative embodiment, it is possible to envisage re-authorizing the operation of the MF engine only after a check and possible repair of the vehicle V and an update of at least one computer of the vehicle V in an after-sales service.

[0086] It will also be noted, as illustrated non-limitingly in Figure 2, that the first calculator CF (or the calculator of the monitoring device DS) can also include a mass memory MM1, in particular for storing the successive measured currents cm, as well as any intermediate data involved in all its calculations and processing. Furthermore, this first calculator CF (or the calculator of the monitoring device DS) may also comprise an input interface IE for receiving at least each measured current cm for use in calculations or processing, possibly after having shaped and / or demodulated and / or amplified it, in a manner known per se, by means of a digital signal processor PR2. In addition, this first calculator CF (or the calculator of the monitoring device DS) may also comprise an output interface IS, in particular for delivering a message (or order) prohibiting operation of the MF engine, a message (or order) authorizing operation of the MF engine, a possible message (or order) for triggering an alert, a possible message (or order) for the end of triggering an alert, and a possible message containing a fault code.

[0087] It will also be noted that the invention also proposes a computer program product (or computer program) comprising a set of instructions which, when executed by processing means of the electronic circuit (or hardware) type, such as for example the processor PR1, is capable of implementing the monitoring method described above to monitor the measured current cm which supplies the motor MF of the brake device DF1 of the vehicle V.

Claims

CLAIMS

1. Monitoring method for a vehicle (V) comprising a transmission chain comprising a brake device (DF1) comprising a wheel (RD) provided with teeth and a brake finger (DF2) suitable for being placed by a motor (MF), supplied by a measurable current, in an immobilization position, in which it is housed between two teeth to immobilize said vehicle (V), or a decoupled position, in which it is decoupled from said wheel (RD), characterized in that it comprises a step (10-50) in which, in the event of authorization of a placement of said brake finger (DF2) in its immobilization or decoupled position, requested by a user, the operation of said motor (MF) is prohibited when said measured current is between first and second thresholds chosen as a function of said requested position for at least a first duration chosen and associated with this first threshold.

2. Method according to claim 1, characterized in that in said step (10-50), in the event of authorization of a placement of said brake finger (DF2) in its immobilized or decoupled position, requested by said user, the operation of said motor (MF) is prohibited when said measured current exceeds said second threshold chosen as a function of said requested position for at least a second chosen duration associated with this second threshold and strictly less than said first duration associated with this first threshold.

3. Method according to claim 2, characterized in that in said step (10-50) said second duration associated with said immobilization position is between 30 ms and 50 ms, and said second duration associated with said decoupled position is between 30 ms and 50 ms.

4. Method according to claim 1, characterized in that in said step (10-50), in the event of authorization of a placement of said brake finger (DF2) in its immobilization or decoupled position, requested by said user, operation of said motor (MF) is authorized when said measured current is lower than a third threshold chosen as a function of said requested position and lower than or equal to said first threshold associated with said position. requested, regardless of the duration.

5. Method according to one of claims 1 to 4, characterized in that in said step (10-50) said first threshold associated with said immobilization position is between 45 A and 55 A, said first threshold associated with said decoupled position is between 40 A and 50 A, said first duration associated with said immobilization position is between 40 ms and 60 ms, and said first duration associated with said decoupled position is between 40 ms and 60 ms.

6. Method according to one of claims 1 to 5, characterized in that in said step (10-50) said second threshold associated with said immobilization position is between 50 A and 60 A, and said first threshold associated with said decoupled position is between 45 A and 55 A.

7. Method according to one of claims 1 to 6, characterized in that in said step (10-50), in the event of prohibition of operation of said engine (MF), at least one complementary action is carried out in said vehicle (V) chosen from a recording of at least one fault code representative of an overcurrent situation at the level of said engine (MF), and a triggering of an alert generation for said user signaling a problem in said transmission chain.

8. Computer program product comprising a set of instructions which, when executed by processing means, is capable of implementing the monitoring method according to one of claims 1 to 7, in a vehicle (V) comprising a transmission chain comprising a brake device (DF1) comprising a wheel (RD) provided with teeth and a brake finger (DF2) capable of being placed by a motor (MF), powered by a measurable current, in an immobilization position, in which it is housed between two teeth to immobilize said vehicle (V), or a decoupled position, in which it is decoupled from said wheel (RD), to monitor said measured current.

9. Monitoring device (DS) for a vehicle (V) comprising a transmission chain comprising a brake device (DF1) comprising a wheel (RD) provided with teeth and a brake finger (DF2) suitable for being placed by a motor (MF), supplied by a measurable current, in an immobilization position, in which it is housed between two teeth to immobilize said vehicle (V), or a decoupled position, in which it is decoupled from said wheel (RD), characterized in that it comprises at least one processor (PR1) and at least one memory (MD) arranged to carry out the operations consisting, in the event of authorization of a placement of said brake finger (DF2) in its immobilization or decoupled position, requested by a user, in triggering a prohibition of operation of said motor (MF) when said measured current is between first and second thresholds chosen as a function of said requested position for at least a first duration chosen and associated with this first threshold.

10. Vehicle (V) comprising a transmission chain comprising a brake device (DF1) comprising a wheel (RD) provided with teeth and a brake finger (DF2) suitable for being placed by a motor (MF), powered by a measurable current, in an immobilization position, in which it is housed between two teeth to immobilize said vehicle (V), or a decoupled position, in which it is decoupled from said wheel (RD), characterized in that it further comprises a monitoring device (DS) according to claim 9.

Images