ACTIVATION OF POWER SUPPLY TO AN ELECTRONIC BRAKE CONTROL UNIT WHEN THE VEHICLE IS PARKED AND THE PARKING BRAKE IS RELEASED

Abstract

The invention relates to a braking control system (4) for a motorized road vehicle (1). The braking control system (4) comprises a sensor (24) configured to monitor for possible release of a parking brake when the vehicle (1) is parked, and an electronic braking control unit (26, 63) configured to control the braking of the wheel by the brake. The braking control system (4) is configured to reactivate the power supply to the electronic braking control unit (26, 63) to command the re-engagement of the brake (6) when the sensor (24) detects a release of the brake (6) while the vehicle (1) is parked and after the power supply to the electronic braking control unit (26, 63) has been switched off. (Fig. 2)

Description

Title of the invention: ACTIVATION OF THE POWER SUPPLY OF AN ELECTRONIC BRAKE CONTROL UNIT WHEN THE VEHICLE IS PARKED AND THE PARKING BRAKE IS RELEASED Technical field of the invention

[0001] The invention relates to the braking of a motorized road vehicle, such as a car or van. More specifically, the invention concerns the activation of the power supply to an electronic brake control unit when brake release is detected while the vehicle is stopped and parked, and after the power supply to the electronic brake control unit has been switched off. Prior art

[0002] Motorized road vehicles such as automobiles include wheel speed sensors, parking brakes, and at least one electronic brake control unit. When the vehicle is parked, the power supply to the electronic brake control unit and to each sensor is maintained for a monitoring period, in order to trigger the re-engagement of the parking brakes if necessary.

[0003] There is a need to limit energy consumption when a vehicle is stopped, while tending to maintain or improve vehicle safety, in particular by allowing a satisfactory tightening of a brake when the vehicle is stopped, in particular by allowing a parking brake to be tightened when the vehicle is parked. Description of the invention

[0004] The invention aims to overcome all or part of the drawbacks of the prior art. In this regard, the invention relates to a braking control system for a motorized road vehicle. The braking control system comprises an electronic braking control unit configured to control the braking of a wheel of the vehicle by means of a wheel parking brake. The power supply to the electronic braking control unit is cut off when the vehicle is parked, i.e., when the parking brake is engaged. The parking brake can be engaged manually or automatically.

[0005] According to the invention, the brake control system includes a sensor that is configured to monitor for possible release of the parking brake when the vehicle is parked. The brake control system is configured to activate The power supply to the electronic brake control unit (EBCU) is used to trigger brake re-tensioning when the sensor detects brake release while the vehicle is parked, after the EBCU's power supply has been switched off. Such re-tensioning can occur, for example, during brake cooling for a disc brake, or if the brake is not fully engaged when the parking brake is activated for a disc or drum brake. This results in a reduction in the energy consumption of at least one EBCU.

[0006] Thanks to the braking control system as claimed, energy consumption is limited when the vehicle is stopped, while also tending to improve vehicle safety. The braking control system according to the invention also potentially contributes to limiting the mass and size of a braking system, and / or to increasing the service life of the braking system.

[0007] The vehicle's energy consumption is limited by reducing the energy consumption of at least one electronic brake control unit, by cutting off the power supply to the electronic brake control unit earlier when no brake release is detected. Vehicle safety is improved by tending to monitor brake release by the sensor for a longer period, particularly with substantially equivalent energy consumption of the brake control system compared to a known braking system. Vehicle safety tends to increase by allowing the brake to remain adequately applied when the vehicle is stopped, in particular by allowing the brake to be reapplied when the vehicle is parked.

[0008] By facilitating brake re-engagement when the vehicle is stationary, the frequency of high-intensity braking and / or the average braking intensity of the parking brake are limited. This makes it possible to reduce the power and dimensions of the brake. The mass and size of the brake, and more generally of the braking system, are reduced. The energy consumption of the braking system is further decreased.

[0009] By limiting high-intensity braking and / or the average braking intensity by the brake, the brake and more generally the braking system are less stressed and the life of the braking system tends to increase, in particular with substantially equivalent dimensions of the brakes compared to a known braking system.

[0010] According to one embodiment, the braking control system is configured to maintain the power supply to the sensor after the vehicle has stopped for a monitoring period which is greater than or equal to a vigilance period during which the electronic braking control unit is powered.

[0011] Preferably, the brake control system is configured to maintain power to the sensor after the vehicle has stopped for a monitoring period which is strictly greater than a period of vigilance during which the electronic braking control unit is powered, particularly when the road is sloping.

[0012] Preferably, the monitoring time is determined from a temperature of the parking brake when the vehicle stops and / or from an inclination of a slope on which the vehicle is located.

[0013] According to one embodiment, the braking control system is configured to deactivate the power supply to the electronic braking control unit after the elapsed vigilance period following the stopping of the vehicle in the absence of release of the parking brake.

[0014] According to another embodiment, the brake control system is configured to deactivate the power supply to the electronic brake control unit after the elapsed vigilance period following tightening of the parking brake.

[0015] Preferably, the vigilance period is a predetermined duration. The vigilance period lasts, for example, fifteen seconds.

[0016] According to one particular embodiment, the brake is a disc brake.

[0017] According to another embodiment, the parking brake is an electromechanical brake comprising a geared motor which includes an electric motor and a gearbox. The parking brake includes the electronic brake control unit.

[0018] According to one embodiment, the sensor includes a wheel speed sensor. The wheel speed sensor is configured to detect the release of the parking brake by measuring the wheel's rotational speed. Preferably, the wheel speed sensor includes a magnetic field variation sensor, for example, a Hall effect sensor.

[0019] According to another embodiment, the sensor includes a brake motor drive sensor. The brake motor drive sensor is configured to detect the activation of an electric brake motor when the parking brake is released and the wheel is rotating.

[0020] Preferably, the electric brake motor drive sensor includes a back electromotive force sensor that is configured to monitor the release of the parking brake by measuring a back electromotive force that is generated by the drive of an electric brake motor.

[0021] According to one embodiment, the brake control system includes a signal comparator which is configured to compare a signal representative of parking brake release to at least one brake release threshold value.

[0022] Preferably, the signal comparator comprises a hysteresis comparator with a first brake release threshold value and a second brake release threshold value. The hysteresis comparator is, in particular, a Schmitt flip-flop voltage comparator.

[0023] According to another embodiment, the brake control system includes a switch that is configured to activate the power supply to the electronic brake control unit when a brake release is detected before the expiration of the monitoring time and after the power supply to the electronic brake control unit has been cut off.

[0024] Preferably, the switch includes a toggle. The toggle is in particular an RS lock with a not-or gate.

[0025] The energy consumption of the braking control system tends to decrease further when the braking system is at least partially distributed by including electronic braking control units, for example a central electronic braking control unit and local electronic braking control units that are part of the brakes.

[0026] Vehicle safety tends to be significantly improved by allowing longer monitoring of possible brake release when the vehicle is stopped, when the brake includes a reversible mechanical transmission and there is a higher risk of brake release.

[0027] Vehicle safety tends to increase significantly by facilitating the tightening of a brake whose loosening would be caused by cooling of the brake when the vehicle is stopped, in particular parked, and in particular when the sensor is a wheel rotation speed sensor.

[0028] The invention also relates to a method for controlling the braking of a motorized road vehicle, which is implemented by means of a braking control system as defined above. The braking control method includes a vehicle parking step, the sensor remaining powered for a monitoring period after the vehicle has stopped and the power supply to the electronic braking control unit being cut off.

[0029] The brake control method includes activating the power supply to the electronic brake control unit to command the re-tightening of the brake, when the sensor detects a release of the brake while the vehicle is parked and after the power supply to the electronic brake control unit has been cut off. Brief description of the figures

[0030] The present invention will be better understood upon reading the description of examples non-limiting implementation, with reference to the attached figures, which illustrate: • [Fig.1]: a schematic representation of a vehicle comprising a braking system which includes a braking control system according to the invention; • [Fig. 2]: A schematic representation of a control system braking according to a first embodiment; • [Fig. 3]: a schematic representation of a control system braking according to a second embodiment; • [Fig. 4]: The operation of the braking control system according to the first embodiment or according to the second embodiment, in the absence of brake release; • [Fig. 5]: Implementation of a braking control method according to the invention; • [Fig. 6]: the variation of a monitoring duration based on the inclination of a slope and brake temperature during the implementation of the braking control method according to the invention. DETAILED description of AT LEAST ONE embodiment

[0031] For clarity, identical elements are identified by identical reference signs from one figure to another.

[0032] Figure 1 represents a motorized road vehicle 1 comprising a braking system 2, wheels 10, and a battery 5. The motorized road vehicle 1 is, for example, a car or a van. The vehicle 1 preferably comprises four wheels 10.

[0033] In this document, an axial direction XX is a direction that is parallel to the longitudinal direction of the vehicle; it is also called the front-to-rear direction of vehicle 1. A transverse direction YY is a direction that is perpendicular to the axial direction XX and corresponds to a lateral direction of the vehicle; it is also called the left-to-right direction of vehicle 1. A height direction ZZ is a direction of the height of the vehicle; it is perpendicular to the axial direction XX and to the transverse direction YY.

[0034] The braking system 2 includes a brake control system 4, brakes 6, a brake pedal 22, a parking brake actuator 28, a main brake circuit 20 and a parking brake circuit 30. The braking system 2 is configured to brake the vehicle 1.

[0035] The brakes 6 are configured to brake the wheels 10 of the vehicle 1. The braking system 2 includes, for example, a first front right brake 6FR to brake a front right wheel of the vehicle 10FR, a front left brake 6FL to brake a front left wheel 10FL of the vehicle, a rear right brake 6RR to brake a rear wheel The right-hand 10RR of the vehicle, and a left-hand rear 6RL to brake a left-hand rear wheel 10RL. The front brakes 6FR, 6FL are located laterally on either side of a front axle. The rear brakes 6RR, 6RL are located laterally on either side of a rear axle of vehicle 1. In this example, the brakes 6 are disc brakes. The brakes 6 are electromechanical parking brakes, and the brakes 6 are hydraulic or electromechanical for service braking. The parking brakes are preferably the rear brakes 6RL, 6RR. The parking brakes are preferably the emergency brakes of vehicle 1.

[0036] The brake 6 is hydraulic when it includes a hydraulic actuator. The brake 6 is electromechanical when it includes an electromechanical actuator 60. Each brake 6 includes an electromechanical actuator 60 and / or a hydraulic actuator. Each hydraulic actuator includes a piston 67 and a hydraulic chamber 62.

[0037] Each electromechanical actuator 60 comprises a geared motor 68. The geared motor 68 includes an electric motor 69 and a gearbox. When the brake 6 is electromechanical, the brake 6 includes, in particular, a local electronic control unit 63 and a local power supply control unit 65 for the geared motor. The local electronic control unit 63 and the local power supply control unit 65 are part of the braking control system 4.

[0038] With more specific reference to [Fig. 3], the brake 6 shown is a disc brake. The disc brake comprises a caliper 64, a disc 61, and brake pads 66. The disc brake shown is a floating caliper disc brake. The disc brake shown is electromechanical for the parking brake.

[0039] The electromechanical actuator 60 includes, in particular, a mechanical transmission 70, which is, for example, reversible. In this example, the mechanical transmission 70 comprises a screw 71 and a nut 73. One of the screw 71 and nut 73, here the screw 71, is a driving element that is movable in rotation and fixed in translation about a longitudinal axis Y1-YL. The other of the screw 71 and nut 73 is a driven element that is movable in translation and fixed in rotation about the longitudinal axis Y1-YL. The mechanical transmission 70, which is represented in [Fig. 3], is reversible; the mechanical transmission 70 comprises a locking mechanism that is configured to lock the brake 6 in the braking position and that includes a locking latch 75.

[0040] With further reference to [Fig. 1], the brake pedal 22 is configured to be operated by the user's foot during vehicle service braking. A central electronic brake control unit 26 is specifically configured to immobilize the vehicle in parking brake mode when the vehicle 1 is traveling at low speed, for example less than 5 km / h.

[0041] The main braking circuit 20 includes braking control lines of The front service brake control lines 21 (left and right) and the rear service brake control lines 23 (left and right) are connected. The front service brake control line 21 (left) connects, for example, the front left brake 6FL to the central electronic brake control unit 26, to transmit a control signal to the front left brake 6FL. The front service brake control line 21 (right) connects, for example, the front right brake 6FR to the central electronic brake control unit 26, to transmit a control signal to the front right brake 6FR. The rear service brake control line 23 (left) connects, for example, the rear left brake 6RL to the central electronic brake control unit 26, to transmit a control signal to the rear left brake 6RL.The right rear service brake control line 23, for example, connects the right rear brake 6RR to the central electronic brake control unit 26, to transmit a control signal to the right rear brake 6RR. The left and right front service brake control lines 21 are configured to transmit brake commands to the brakes 6. The main brake circuit 20 is configured to transmit a service brake command from the vehicle 1 when the brake pedal 22 is operated by a driver.

[0042] The parking brake control 28 includes a parking brake control button and / or a handbrake lever. The parking brake control 28 is configured to transmit a parking brake and / or safety brake signal to the brake control system 4.

[0043] The parking brake circuit 30 includes parking brake control lines 31, 33, in particular left and right rear parking brake control lines 33 and / or left and right front parking brake control lines 31. The front parking brake control lines 31 connect, for example, the front brakes 6FR, 6FL to the central electronic brake control unit 26. The rear parking brake control lines 33 connect, for example, the rear brakes 6RR, 6RL to the central electronic brake control unit 26. The parking brake circuit 30 is configured to transmit a parking brake command to the brakes 6 via the parking brake control lines 31, 33, when the parking brake control 28 is actuated, in particular to the rear brakes 6RL, 6RR.

[0044] With joint reference to Figures 1 to 3, the brake control system 4 comprises at least one sensor 24, 25 for monitoring brake release, at least one sensor power supply unit, at least one electronic brake control unit 26, 63, and at least one electronic brake unit power supply unit 45 which is configured to electrically power the unit The brake control system 4 includes electronic brake control components 26, 63, and at least one sensor signal processing device 44. The brake control system 4 optionally includes a power supply regulator 47, 49 for the sensor and / or comparator. The brake control system 4 is configured to control the braking of the vehicle 1, specifically the wheels 10, by the brakes 6. In particular, the brake control system 4 is configured to control the reapplication of the parking brakes 6 when a release of the brakes 6 is detected while the vehicle 1 is parked, at least when there is a slope.

[0045] With specific reference to the embodiments shown, the braking control system 4 comprises electronic braking control units 26, 63. The braking control system 4 is at least partially distributed, comprising, for example, the central electronic braking control unit 26 and local electronic control units 63 for each brake 6. The braking control system 4 includes a power supply unit for the central electronic braking control unit to provide electrical power to the central electronic braking control unit 26. The braking control system 4 includes power supply units for the electronic braking control unit 45 to provide electrical power to each local electronic braking control unit 63.

[0046] The braking control system 4 is configured to maintain power to each electronic braking control unit 26, 63 for a duration of vigilance tl. The braking control system 4 is configured to cut off the power supply to each electronic braking control unit 26, 63 after the expiration of the vigilance tl following the stopping of vehicle 1 during parking of vehicle 1, in particular in the absence of release of the parking brakes 6.

[0047] The vigilance time tl is a predetermined duration, for example fifteen seconds. The vigilance time tl elapses from the moment vehicle 1 comes to a stop, when vehicle 1 is parked. The vigilance time tl is interrupted by the tightening of at least one of the brakes 6. The vigilance time tl is, for example, reset after the tightening of brake 6 when brake 6 has been tightened.

[0048] The brake control system 4 is configured to maintain power to each sensor 24, 25 for a monitoring period t2, particularly after the power to the electronic brake control unit 26, 63 has been cut off in the event of a slope and / or risk of brake release 6. The brake control system 4 is configured to cut off the power supply to each brake release sensor 24, 25 after the monitoring period t2 has elapsed following the vehicle 1 stopping during vehicle 1 parking, particularly in the absence of release of the parking brakes 6.

[0049] The monitoring time t2 is determined from a temperature T of each brake 6 when the vehicle 1 stops and / or from the incline a of a slope on which the vehicle 1 is located. The monitoring time t2 starts from the moment the vehicle 1 stops, when the vehicle 1 is parked. The monitoring time t2 may be interrupted and reset after each brake 6 is tightened. The monitoring time t2 is greater than or equal to the vigilance time. In particular, the monitoring time t2 is strictly greater than the vigilance time t1 when the vehicle 1 is stopped on a slope and / or if there is a risk of the parking brake 6 releasing.

[0050] Figure 6 illustrates, by way of example, the variation 300 of the monitoring time t2 based on the temperature T of the parking brakes 6 and the incline a of a slope on which the vehicle 1 is located. The variation 300 of the monitoring time includes a first zone 301 and a second zone 302, with a gentle slope and / or a low risk of brake release. The monitoring time t2 is, for example, approximately fifteen seconds in the case of a gentle slope and / or a low risk of brake release. In the first zone 301 and in the second zone 302, the vigilance time t1 and the monitoring time t2 are, in particular, equal. The power supply to each electronic brake control unit 26, 63 and to each sensor 24, 25 is switched off almost immediately after the vehicle 1 comes to a stop, when the vehicle is parked.

[0051] The variation 300 of the monitoring time includes a third zone 303 with a moderate gradient and / or a moderate risk of brake 6 release. The moderate gradient is, for example, less than 20% or 25%. The moderate risk of brake 6 release occurs, for example, when the brake 6 has a reversible mechanical transmission 70 and / or when the temperature T of the brake 6 is above a temperature threshold value, for example, 200°C–250°C. The monitoring time t2 is, for example, approximately five minutes. In the third zone 303, the monitoring time t2 is strictly greater than the vigilance time t1, on the order of ten to thirty times greater than the vigilance time t1. The power supply to each electronic brake control unit 26, 63 is cut off almost immediately after the vehicle 1 stops, when the vehicle 1 is parked.The power supply to each sensor 24, 25 is maintained throughout the monitoring period t2 to monitor for any possible release of brake 6, in particular the parking brake.

[0052] The variation 300 of the monitoring time includes a fourth zone 304 with a steep incline and a high risk of brake 6 release. The steep incline is, for example, greater than or equal to 25%. The high risk of brake 6 release occurs, for example, when the brake 6 is transmission-driven. The reversible mechanical system 70 and / or when the brake temperature T of the brake 6 exceeds a temperature threshold value, for example, 250°C. The monitoring period t2 is, for example, approximately fifty minutes. In the fourth zone 304, the monitoring period t2 is strictly greater than the vigilance period t1, on the order of one hundred to three hundred times greater than the vigilance period t1. The power supply to each electronic brake control unit 26, 63 is cut off almost immediately after the vehicle 1 comes to a stop, when the vehicle is parked. The power supply to each sensor 24, 25 is maintained throughout the monitoring period t2 to monitor for any possible release of the brake 6, in particular the parking brake.

[0053] The brake control system 4 is configured to activate the power supply to each electronic brake control unit 26, 63 of parking brakes to command the tightening of each parking brake 6, when at least one sensor 24, 25 detects a loosening of at least one of the parking brakes 6 of the vehicle 1 when the vehicle is parked and after the power supply to each electronic brake control unit 26, 63 has been cut off.

[0054] More generally, the brake control system 4 is configured to activate the power supply to at least one electronic brake control unit 26, 63 to command the tightening of at least one brake 6 when at least one sensor 24, 25 detects a loosening of at least one of the brakes 6 of the vehicle 1 when the vehicle is stopped and after the power supply to the electronic brake control unit 26, 63 has been cut off.

[0055] The braking control system 4 is configured in particular to deactivate the power supply to each electronic braking control unit 26, 63 after the elapsed vigilance time t1 following the tightening of at least one of the brakes 6 of vehicle 1. The braking control system 4 is configured in particular to deactivate the power supply to each sensor 24, 25 after the elapsed monitoring time t2 following the tightening of the brake 6 of at least one of the brakes 6 of vehicle 1.

[0056] The central electronic brake control unit 26 is common to the brakes 6 of the braking system 2, in particular the parking brakes 6. It includes, for example, a microcontroller. The central electronic brake control unit 26 is configured to control the braking of the vehicle 1 when the driver presses the brake pedal 22, in particular the service braking of the vehicle. The central electronic brake control unit 26 is configured to control the parking braking of the vehicle 1, for example when the parking brake control 28 is activated by the user or when the brake pedal 22 is activated and the vehicle 1 is moving at low speed. The central electronic brake control unit 26 is configured, in particular, to command the local electronic braking control units 63 to brake the corresponding brake 6, in particular in parking braking.

[0057] With joint reference to Figures 1 to 3, each local electronic control unit 63 for the electromechanical brake is a brake control electronic unit. It includes, for example, a microcontroller. The local electronic control unit 63 is configured to control the operation of the electromechanical actuator 60, in particular during parking braking of the vehicle 1 and / or especially upon command from the central electronic brake control unit 26. The local electronic control unit 63 includes, for example, a connection and data transmission unit for a data exchange network such as a CAN-type digital network. The local electronic control unit 63 may optionally include the local power supply control unit 65.

[0058] The local power supply control unit 65 is configured to electrically supply the electromechanical brake geared motor 68 from the energy supplied by the battery 5, in particular upon command from the local electronic control unit 63 and / or the central brake control electronics 26. The local power supply control unit 65 is configured to electrically supply the electric motor 69 of the geared motor. The local power supply control unit 65 includes, for example, an inverter.

[0059] Each sensor 24, 25 is configured to monitor the release of one of the brakes 6 when the vehicle 1 is stopped. In particular, each sensor 24, 25 is configured to monitor the release of a parking brake 6 when the vehicle 1 is parked. The first embodiment shown in [Fig. 2] differs mainly from the second embodiment shown in [Fig. 3] by the nature of the sensors 24, 25.

[0060] With reference to the first embodiment, which is shown in [Fig. 2], each sensor 24, 25 is a wheel speed sensor 24 (or wheel angular position sensor). Each wheel speed sensor 24 is configured to measure the rotational speed of the corresponding wheel 10, for example, in the direction CL. Each wheel speed sensor 24 is configured to monitor the release of the corresponding brake 6, in particular a parking brake, by measuring the rotational speed of the wheel 10. The wheel speed sensor 24 detects the release of the brake 6 when the wheel speed sensor 24 measures a non-zero rotational speed of the wheel 10 that was held by the brake 6. The wheel speed sensor 24 is, in particular, a magnetic field variation sensor. The wheel speed sensor 24 is, for example, a Hall effect sensor.

[0061] With reference to the second embodiment, which is shown in [Fig. 3], each sensor 24, 25 is a brake motor drive sensor 25. Each sensor The brake motor drive sensor 25 is configured to detect the activation of an electromechanical brake electric motor 69 when the brake 6 is released, the wheel 10 is rotating, and the brake geared motor 68 is driven in generator mode. The brake motor drive sensor 25 includes a back electromotive force (EMF) sensor configured to measure the back EMF generated by the drive of the brake electric motor 69 in a direction C2. The brake motor drive sensor 25 is configured to monitor the release of the brake 6, which would occur, in particular, by piston recoil, by measuring the back EMF generated by the drive of the electromechanical brake geared motor 68 as a result of this recoil.

[0062] With reference to the two embodiments shown and to [Fig. 2], each sensor signal processing device 44 comprises a filtering device 41, a signal comparator 42, a switch 46, and a diode 43. The sensor signal processing device 44 is configured to process the signal from the sensor 24, 25 before transmitting it to the power supply unit of the electronic braking unit 45 and / or to the electronic braking control unit 26, 63. The braking control system 4 includes, in particular, one sensor signal processing device 44 for each sensor 24, 25.

[0063] Each filtering device 41 is configured to filter noise from the wheel loosening monitoring signal originating from at least one of the sensors 24, 25. The filtering device 41 includes, in particular, a low-pass filter. The low-pass filter includes, for example, an RC filter comprising a resistor and a capacitor.

[0064] Each signal comparator 42 is configured to compare a representative brake release signal 6 from at least one of the sensors 24, 25, and after filtering, to at least one brake release threshold value. The signal comparator 42 is, in particular, a hysteresis comparator with a first brake release threshold value 6 and a second brake release threshold value. The signal comparator 42 is, for example, a Schmitt flip-flop voltage comparator.

[0065] With reference to [Fig.2] and the first embodiment, the signal comparator 42 is configured to compare a wheel speed signal after filtering to at least one wheel speed threshold value which is representative of brake 6 release through a wheel 10 rotation Cl.

[0066] With reference to [Fig.3] and the second embodiment, the signal comparator 42 is configured to compare a back electromotive force signal, within the electric motor 69, to at least one threshold value of back electromotive force which is representative of brake release and drive of the electric motor 69 of electromechanical brake.

[0067] With reference to the two embodiments shown and to [Fig. 2], the switch 46, or "latch" in Anglo-Saxon terminology, comprises a toggle switch that is an RS latch with a non-OR gate. The switch 46 is configured to automatically activate and / or deactivate the power supply to the electronic brake control unit 26, 63 based on the representative brake release signal and the monitoring time t2. More specifically, the switch 46 is configured to deactivate the power supply to the electronic brake control unit 26, 63 after the elapsed monitoring time t1 following a stop with the parking brake 6 activated, or after the brake 6 is reapplied.The switch 46 is configured to activate the power supply to the electronic brake control unit 26, 63 when a release of the brake 6 is detected during the monitoring time t2 determined after the vehicle 1 has stopped with the parking brake 6 activated or after the brake 6 has been tightened and after the power supply to the electronic brake control unit 26, 63 has been cut off.

[0068] The RS lock comprises a first control input S, a second control input S, a first control output Q, and optionally a second output. The first control input is also called set S; it is, for example, connected to the comparator 42. The second control input is also called reset R; it is, for example, connected to an output C of the electronic control unit 26, 63 to reset the RS lock after the monitoring time t2 has elapsed in the absence of brake release 6. The first control output Q is the main control output; it is used, for example, to activate the power supply to the electronic brake control unit 26, 63 when brake release 6 has been detected. The RS lock optionally comprises a second control output that corresponds to the complement of the main output Q.

[0069] In each of the embodiments shown, the brake control system 4 includes a power supply regulator 47, 49 for the sensor and / or the sensor signal processing device. More specifically, the brake control system 4 includes a power supply regulator 47 for the sensor to regulate the power supply to the sensor 24, 25, and the brake control system 4 includes a power supply regulator 49 for the sensor signal processing device to regulate the power supply to the comparator 42 and the switch 46.

[0070] The sensor power supply regulator 47 includes, for example, a voltage regulator configured to limit fluctuations in the sensor 24, 25 supply voltage. The sensor power supply regulator 47 is configured to supply electrical power to the sensor 24, 25 from a vehicle battery 5. The sensor power supply regulator 47 is configured to cut off the power supply to the sensor 24, 25, in particular upon command from the unit brake control electronics 26, 63.

[0071] The power supply regulator 49 for the sensor signal processing device includes, for example, a voltage regulator that is configured to limit supply voltage fluctuations to the comparator 42 and the switch 46. The power supply regulator 49 for the sensor signal processing device is configured to supply the comparator 42 and the switch 46 electrically from a battery 5 of the vehicle 1. The power supply regulator 49 for the sensor signal processing device is configured to cut off the power supply to the comparator 42 and the switch 46, in particular on command from the electronic brake control unit 26, 63.

[0072] Figures 4 and 5 illustrate the braking control method 100 of a vehicle 1 by means of a braking control system 4 according to the first embodiment or the second embodiment. The braking control method 100 includes a vehicle stopping step 101, during which the power supply to at least one sensor 24, 25 is maintained for the monitoring duration t2 and the power supply to the electronic braking control unit 26, 63 is maintained for the vigilance duration t1. In particular, the power supply to each parking brake release sensor 24, 25 is maintained for the monitoring duration t2.

[0073] In the absence of a slope and / or in the absence of risk of brake release 6, particularly parking brakes, the braking control method 100 continues with a parking step in the absence of a slope and / or risk of brake release 102, during which the monitoring time t2 is equal to the vigilance time t1. The power supply to each sensor 24, 25 and each electronic braking control unit 26, 63 is switched off after the vigilance time t1 has elapsed, at least in the absence of brake release.

[0074] In the presence of a moderate to steep incline and / or a moderate to high risk of brake release 6, the braking control method 100 continues with a parking and standby stage 103 during which the power supply to the brake release sensor 24, 25 is maintained for the monitoring period t2 if no brake release is detected, and the power supply to the electronic braking control unit 26, 63 is cut off after the elapsed vigilance period t1. In particular, the power supply to each parking brake release sensor 24, 25 is maintained for the monitoring period t2 if no parking brake release is detected, and the power supply to each electronic parking brake control unit 26, 63 is cut off after the elapsed vigilance period t1.

[0075] In particular, it is checked during a comparison step of duration 105 whether the duration of vigilance tl and / or if the monitoring time t2 have expired, after the parking stage in the absence of slope and / or risk of brake release 102 or after the parking and watch stage 103.

[0076] When the monitoring time t2 has elapsed without any detection of brake re-engagement 6, the brake control process 100 continues by cutting off the power supply to the sensor 24, 25 during a sensor power-off step 107. In particular, the brake control process 100 continues by cutting off the power supply to each parking brake release sensor 24, 25 when the monitoring time t2 has elapsed without any detection of parking brake re-engagement. The energy consumption of the vehicle 1, particularly of the brake control system 4, becomes minimal to conserve the battery 5 during a complete vehicle stop step 109.

[0077] If it is determined in the time comparison step 105 that the vigilance time t1 has elapsed and the monitoring time t2 has not yet elapsed, it is checked during a brake release monitoring step 201 whether at least one brake 6, in particular a parking brake, has released and in particular whether the corresponding wheel 10 has turned.

[0078] If it is detected that the brake 6 has released during the release monitoring step 201, a brake 6 tightening procedure 200 is initiated. The power supply to the electronic brake control unit 26, 63 is activated, and the electronic brake control unit 26, 63 commands the tightening of the released brake 6 during a step 203 that reactivates the power supply to the local electronic control unit. For example, the electronic brake control units 26, 63 command the tightening of each parking brake 6 when the release of at least one parking brake has been detected.

[0079] The braking control method 100 includes a braking and brake application verification step 205 when the electronic braking control unit 26, 63 commands the application of the brake 6. In particular, the braking control method 100 includes a braking step by each parking brake and a verification step for each parking brake. The parking of the vehicle 1 can then continue.

[0080] Once the brake 6 is engaged, the braking control method 100 includes a standby control check step 207 during which the braking control system 4 checks whether braking is complete and the brake 6 is engaged. In particular, the braking control system 4 checks whether parking braking is complete and each parking brake 6 is engaged. If so, the braking control system 4 essentially returns to the vehicle stop step 101, with the monitoring time t2 being interrupted and reset.

[0081] Thanks to the braking control system 4, energy consumption is limited when the vehicle 1 is stopped, while also tending to improve the safety of the vehicle 1. The braking control system 4 according to the invention also possibly contributes to limiting the mass and size of a braking system 2, and / or to increasing the service life of the braking system 2.

[0082] The energy consumption of vehicle 1 is limited by reducing the energy consumption of at least one electronic brake control unit 26, 63, by cutting off the power supply to the electronic brake control unit 26, 63 earlier when no brake release 6 is detected. The safety of vehicle 1 is improved by monitoring brake release 6 for a longer period by the sensor 24, 25, particularly with substantially equivalent energy consumption of the brake control system 4 compared to a known braking system 2. The safety of vehicle 1 is further increased by allowing satisfactory application of the brake 6 when vehicle 1 is stopped, in particular by allowing the brake 6 to be reapplied when vehicle 1 is parked.As an example, the power consumption of the braking control system 4 can be reduced by a factor of 10 to 20 when it switches from the vigilance phase to the monitoring phase, for example by reducing the current from 250mA to 15mA per brake 6. For a 50Ah battery 5 and a monitoring duration t2 of 50 minutes, the total power consumption during parking can represent approximately 0.04% of its capacity instead of 1.7%. This greatly reduces the risk of battery 5 losing its range, or even of the vehicle 1 being unable to start.

[0083] By facilitating the tightening of the brake 6 when the vehicle 1 is stopped, the frequency of high-intensity braking and / or the average braking intensity of the brake 6 are limited. It is then possible to reduce the power and dimensions of the brake 6. The mass and size of the brake 6, and more generally of the braking system 2, are reduced. The energy consumption of the braking system 2 is further decreased.

[0084] By limiting high-intensity braking and / or average braking intensity by the brake 6, the brake 6 and more generally the braking system 2 are less stressed and the life of the braking system 2 tends to increase, in particular with substantially equivalent dimensions of the brakes 6 compared to a known braking system 2.

[0085] The energy consumption of the braking control system 4 tends to decrease further when the braking system 2 is at least partially distributed by comprising electronic braking control units 26, 63, for example a central electronic braking control unit 26 and local electronic braking control units 63 which are part of the brakes 6.

[0086] The risk of brake 6 loosening is higher when the brake 6 has a reversible mechanical transmission 70. The safety of the vehicle 1 tends to be significantly improved by allowing for longer monitoring of a possible brake 6 loosening when the vehicle 1 is stopped, when the brake 6 includes a reversible mechanical transmission 70.

[0087] The safety of vehicle 1 tends to increase substantially by facilitating the tightening of a brake 6, the tightening of which would be caused by cooling of the brake 6 when the vehicle 1 is stopped, in particular parked, and in particular when the sensor 24, 25 is a wheel rotation speed sensor 24.

[0088] Of course, various modifications can be made by a person skilled in the art to the invention which has just been described without going out of the scope of the disclosure of the invention.

[0089] Alternatively, vehicle 1 comprises three wheels such as a bicycle or more than four wheels such as a truck.

[0090] Alternatively, the disc brake is a disc brake with a fixed caliper. Alternatively, brake 6 is a drum brake and a disc brake, for example, a "drum-in-hat" type brake. Alternatively still, each parking brake is, for example, an electromechanical drum brake.

[0091] In addition or alternatively, the mechanical transmission 70 of the electromechanical brake 6 is irreversible. In this case, the mechanical transmission 70 lacks a locking mechanism in the braking position.

[0092] Alternatively, the braking control system 4 comprises a single electronic braking control unit, instead of the central electronic braking control unit 26 and the local braking control units 23.

[0093] Alternatively, the central electronic brake control unit 26 and / or at least one local electronic brake control unit 63 includes a microprocessor.

[0094] In addition or alternatively, the brake control system 4 is configured to command the tightening of the service brakes when a parking brake release is detected when the vehicle is parked and after the power supply to each electronic brake control unit 26, 63 has been cut off.

[0095] Alternatively, the local power supply control unit 65 of the electromechanical brake is configured to electrically supply the electronic brake control unit 63, in particular a microprocessor and / or the microcontroller of the electronic brake control unit 63. The local power supply control unit 65 includes, for example, a voltage regulator to electrically supply the electronic brake control unit 63 from the battery 5 of the vehicle 1.

[0096] The braking control system 4 is then configured in particular to control the activation of the local power supply control unit 65 for

[0097]

[0098]

[0099] supplying electrical power to the electronic brake control unit 63 so that the electronic brake control unit 63 commands the geared motor 68 to tighten the brake 6, when a release of the brake 6 is detected when the vehicle 1 is stopped and after the power supply to the electronic brake control unit 63 has been cut off. Alternatively, the monitoring time t2 does not stop when the brake 6 is tightened and / or it is not reset after the brake is tightened. Alternatively, sensor 24, 25 includes an angular position sensor of the electric motor, for example a Hall effect sensor. LIST OF DIGITAL REFERENCES 1 Motorized road vehicle 2 Braking system 4 Braking control system 5 Vehicle battery 6FL Front left brake 6FR Front right brake 6RL Rear left brake 6RR Rear right brake 6 Brake 10FL Front left wheel 10FR Front right wheel 10RL Rear left wheel 10RR Rear right wheel 10 Wheel 20 Main braking circuit 21 Front service brake control line 22 Brake pedal 23 Rear service brake control line 24 Wheel speed sensor 25 Back EMF sensor 26 Central electronic brake control unit 28 Parking brake actuator 30 Parking brake circuit 31 Front parking brake control line 33 Rear parking brake control line 41 Filtering device 42 Comparator 43 Diode 44 Sensor signal processing device 45 Central electronic brake control unit power supply 46 Switch 47 Sensor power regulator 49 Sensor signal processing device power regulator 60 Electromechanical actuator 61 Disc 62 Hydraulic chamber 63 Local electronic brake control unit 64 Caliper 65 Local power control unit 66 Pad 67 Piston 68 Gearmotor 69 Electric brake motor 70 Mechanical transmission 71 Screw 73 Nut 75 Locking latch 100 Brake control procedure 101 Vehicle stopping 102 Vehicle parking when there is no slope or risk of brake release 103 Vehicle parking and standby 105 Duration comparison 107 Sensor power cut-off 109 Vehicle complete stop 200 Brake tightening procedure 201 Release check 203 Local electronic control unit power reactivation 205 Braking and brake tightening check 207 Standby control check Cl Wheel rotation direction C2 Electric brake motor rotation direction Yl-Yl Longitudinal disc brake axis tl Standby time t2 Monitoring time 300 Monitoring time variation 301 First zone 302 Second zone 303 Third zone 304 Fourth zone

Claims

Demands

1. A braking control system (4) for a motorized road vehicle (1), comprising an electronic braking control unit (26, 63) configured to control the braking of a wheel (10) of the vehicle by means of a parking brake (6) of the wheel (10), the power supply to the electronic braking control unit (26, 63) being cut off after the vehicle (1) is parked, characterized in that the braking control system (4) comprises a sensor (24, 25) configured to monitor for possible release of the parking brake (6) when the vehicle (1) is parked, the braking control system (4) is configured to reactivate the power supply to the electronic braking control unit (26, 63) to control the re-engaging of the parking brake (6), when the sensor (24,25) detects a release of the parking brake (6) when the vehicle (1) is parked and after the power supply to the electronic brake control unit (26, 63) has been switched off.

2. Brake control system (4) according to the preceding claim, wherein the brake control system (4) is configured to maintain the supply of the sensor (24, 25) after the vehicle (1) has stopped for a monitoring time (t2) which is greater than a vigilance time (t1) during which the electronic brake control unit (26, 63) is supplied, the monitoring time (t2) preferably being determined from a temperature (T) of the parking brake (6) when the vehicle (1) stops and / or from an inclination (a) of a slope on which the vehicle (1) is located.

3. Brake control system (4) according to any one of the preceding claims, wherein the brake control system (4) is configured to disable the power supply to the electronic brake control unit (26, 63) after the elapsed time of vigilance (tl) following the vehicle (1) coming to a stop in the absence of the parking brake (6) being released, and / or wherein the brake control system (4) is configured to disable the power supply to the electronic brake control unit (26, 63) after the elapsed time of vigilance (tl) following the tightening of the parking brake (6), the vigilance time (tl) preferably being a predetermined duration, in particular fifteen seconds.

4. Braking control system (4) according to any one of the re- previous sales, in which the brake (6) is a disc brake.

5. Brake control system (4) according to any one of the preceding claims, wherein the parking brake (6) is an electromechanical brake which includes a geared motor (68) which comprises an electric motor (69) and a reducer, the parking brake (6) comprising the electronic brake control unit (63).

6. A braking control system (4) according to any one of the preceding claims, wherein the sensor (24, 25) comprises a wheel speed sensor (24), the wheel speed sensor (24) being configured to detect the release of the parking brake (6) by measuring a rotational speed of the wheel (10), the wheel speed sensor (24) preferably comprising a magnetic field variation sensor, in particular a Hall effect sensor.

7. A brake control system (4) according to any one of the preceding claims, wherein the sensor (24, 25) comprises a brake motor drive sensor (25), the brake motor drive sensor (25) being configured to detect the drive of an electric brake motor (69) when the parking brake (6) is released and the wheel (10) is rotating, the electric brake motor drive sensor (25) preferably comprising a back electromotive force sensor that is configured to monitor the release of the parking brake (6) by measuring a back electromotive force that is generated by the drive of an electric brake motor (69).

8. Brake control system (4) according to any one of the preceding claims, wherein the brake control system (4) comprises a signal comparator (42) that is configured to compare a representative brake release signal to at least one brake release threshold value, the signal comparator (42) preferably being a hysteresis comparator with a first brake release threshold value and a second brake release threshold value, in particular a Schmitt flip-flop voltage comparator.

9. Brake control system (4) according to any one of the preceding claims 2 to 8, wherein the brake control system (4) comprises a switch (46) that is configured to activate the power supply to the electronic brake control unit (26, 63) when a release of the brake (6) is detected before the elapse of the monitoring time (t2) and after the power supply to the electronic brake control unit (26, 63) has been cut off, the switch (46) preferably comprising a toggle, in particular an RS lock with a non-or gate.

10. A braking control method (100) of a motorized road vehicle (1), which is implemented by means of a braking control system (4) according to any one of the preceding claims, wherein the braking control method (100) comprises a vehicle (1) parking step, the sensor (24, 25) remaining energized for a monitoring period (t2) after the vehicle (1) has stopped and the power supply to the electronic braking control unit (26, 63) has been cut off, the braking control method (100) comprising activating the power supply to the electronic braking control unit (26, 63) to command the re-tensioning of the brake (6), when the sensor (24, 25) detects a release of the brake (6) while the vehicle (1) is parked and after the power supply to the electronic braking control unit (26, 63) has been cut off.