DE102023203549A1 - Electromechanically operated wheel brake with central control electronics - Google Patents

Abstract

The invention generally relates to a preferably electromechanically operable wheel brake with control electronics and to an electromechanical braking system for a motor vehicle with such wheel brakes with control electronics.
The wheel brake comprises a brake unit which is assigned to a vehicle wheel of the motor vehicle, wherein the brake unit has at least one electric motor-operable actuator with an electric motor and a transmission, wherein the actuator is designed to generate a defined braking effect on the vehicle wheel, and wherein the brake unit can be controlled by electronic signals.
Furthermore, control electronics are provided, wherein the control electronics are designed to control the actuator and are arranged at a central location on or in the motor vehicle.

Description

The invention generally relates to an electromechanically operable wheel brake with control electronics and to an electromechanical braking system for a motor vehicle with such wheel brakes. The invention also relates to a method for operating such an electromechanically operable wheel brake with control electronics for a motor vehicle.

Electromechanically operated wheel brakes (EMBs) are increasingly being used as service brakes in modern motor vehicles. Such electromechanically operated service brakes typically have an electrically controlled brake unit with an actuator on the vehicle wheels, which interacts with a gearbox. The actual brake is then arranged on the output side of the gearbox, which can, for example, comprise a friction lining that acts on a brake disc. Drum brakes are also conceivable.

Such electromechanically operated wheel brakes offer a number of advantages over conventional, hydraulically operated wheel brakes. A complex hydraulic system is no longer required, and an electromechanical wheel brake also takes up significantly less space. It is also less maintenance-intensive, as, for example, brake fluid does not need to be replaced regularly.

Corresponding brake control units, also known as ECUs, are used to control these brake units. These brake control units can have a power supply for the actuator, corresponding actuators and/or electronic components as well as corresponding communication channels for regulating and controlling the wheel brakes. These brake control units usually include power electronics and/or electronic switching units, in particular microcontrollers, for generating the required control commands for regulating the wheel brake.

The brake control unit is typically, as for example in the document DE 10 2016 221 189 A1 The applicant describes this using the example of a drum brake, and assigns it directly to a brake unit or a wheel brake module. A brake control unit can therefore be assigned directly to a brake calliper or a brake drum and thus to each individual vehicle wheel. This means that a brake control unit of this type is required for each electromechanically operable vehicle wheel.

This can be disadvantageous because the necessary installation space must be reserved for the brake control unit. In addition, complex cabling is required. Finally, a corresponding number of brake control units are required together with the necessary electronic components such as microcontrollers, which can make such solutions quite expensive. What makes matters worse is that these often have to be tailored to the individual vehicle or to the respective wheel brake, which in turn significantly increases the variety of variants. Updating the control algorithms or the software can also prove to be complex with such solutions, since, for example, all brake control units have to be recorded individually during a software update.

Solutions are therefore also known in which certain brake control units of the vehicle wheels are combined and arranged at an adjacent or central location on the body. This can save certain electronic components, as they may only need to be provided once.

However, the effort required for the wiring is particularly disadvantageous here, as in addition to the cables for controlling the actuators on the vehicle wheels, further electrical connections are required to transmit the analog signals from sensors on the vehicle wheel, such as wheel speed sensors or temperature sensors, to the brake control unit for control. If different sensors have to be connected to the brake control unit via several electrical cables, the effort required for the wiring increases enormously.

Mounting the brake control unit on the vehicle wheel adjacent to or in the body can reduce the length of these lines, but not their number, and then again requires the presence of the electronic components in each brake control unit.

Electromagnetic compatibility (EMC) may also be reduced because electromagnetic interference can occur, for example in the area of the power outputs.

What is desirable is an electromechanically operated wheel brake which does not have the disadvantages mentioned above or at least mitigates them.

The aim is to reduce the number of required components, especially electronic ones, in order to save costs.

In addition, it would be beneficial to reduce the overall cabling effort and the length of these typically copper-containing cables.

Finally, electromagnetic compatibility should also be improved or at least not further deteriorated.

The inventors have taken on this task.

This object is achieved surprisingly simply by a braking system having at least two electromechanically actuated wheel brakes as part of a service brake of a motor vehicle, and a method for operating such a braking system according to one of the independent claims.

Preferred embodiments and further developments of the invention can be found in the respective subclaims.

• - jeder Radbremse zumindest eine Bremseinheit zugeordnet ist, welche zumindest einen elektromotorisch betreibbaren Aktuator aufweist, der zur Erzeugung einer Bremskraft eingerichtet ist, ferner aufweisend
• - zumindest einen Sensor, ausgebildet zur Erfassung eines radspezifischen Merkmals,
• - und zumindest eine Ansteuerelektronik mit zumindest einem Mikrocontroller, ausgebildet zur Erzeugung von Regelsignalen zur Ansteuerung der Bremseinheit und/oder der Aktuatoren,
• - wobei die Ansteuerelektronik beabstandet von der Radbremse angeordnet ist, insbesondere räumlich getrennt von der Radbremse in dem Fahrzeugrahmen,
• - wobei zwischen der Ansteuerelektronik und der Bremseinheit zumindest eine Datenleitung vorgesehen ist, welche für die Übertragung der Regelsignale ausgebildet ist, und
• - wobei im Betrieb die durch den zumindest einen Sensor erfassten Messwerte als Sensorsignale über diese zumindest eine Datenleitung an die Ansteuerelektronik übermittelt werden können.

The subject matter of the invention is thus, in a first aspect, a braking system, in particular comprising at least two electromechanically actuated wheel brakes as part of a service brake of a motor vehicle, which are connected to a vehicle frame, wherein

• - each wheel brake is assigned at least one brake unit which has at least one electric motor-operated actuator which is designed to generate a braking force, further comprising
• - at least one sensor designed to detect a wheel-specific feature,
• - and at least one control electronics with at least one microcontroller, designed to generate control signals for controlling the brake unit and/or the actuators,
• - wherein the control electronics are arranged at a distance from the wheel brake, in particular spatially separated from the wheel brake in the vehicle frame,
• - wherein at least one data line is provided between the control electronics and the brake unit, which is designed for the transmission of the control signals, and
• - wherein during operation the measured values recorded by the at least one sensor can be transmitted as sensor signals to the control electronics via this at least one data line.

In the sense of the invention, a motor vehicle means a vehicle with axles, wherein at least one of these axles can comprise steerable wheels and, in addition, the drive of the wheels of at least one axle can be adjusted to suit the specific wheel.

The motor vehicle can comprise an electromechanically actuated wheel brake, also referred to as EMB, on one axle, for example on a rear or a front axle, on the right and left. However, all of the wheel brakes of the motor vehicle can preferably also be designed as electromechanically actuated wheel brakes in the sense of the invention.

The underlying braking system can preferably be designed or used as a service brake. However, it is also possible to use the braking system according to the invention together with a parking brake or to integrate the functionality of a parking brake into the wheel brake according to the invention.

The brake unit can be designed as an electromechanical disc brake, in which a clamping force or application force can be generated by means of the electric motor, the gear and/or a rotation/translation gear or other servomotors. The application force refers to the force with which the brake pads are pressed against the brake disc. During operation, this then generates a braking torque corresponding to a defined braking effect on the wheel in question. Depending on the design and control concept, the control can be selected in such a way that either a predetermined, defined clamping force or a predetermined, defined braking torque is set according to the requested deceleration.

The brake unit can also be designed as an electromechanical drum brake, in which the motor/gear unit actuates a spreading module that presses the brake pads onto the brake drum with a spreading force specified based on the requested desired deceleration and thus generates a corresponding braking torque. Depending on the design and control concept, the control can be designed in such a way that a defined spreading force or a defined braking torque is set according to the desired deceleration.

However, the brake unit can also be used according to further embodiments of the invention on or for a solid disc or multi-disk brake.

The brake system according to the invention can further comprise a brake actuation unit, for example an electric brake pedal. Such an electric brake pedal, also referred to as ePedal, usually has a brake actuation control unit for operation by a vehicle driver, whereby an actuation signal can be detected. Based on this, a braking unit of the respective vehicle wheel can then be controlled.

The wheel brake can be directly assigned to the respective vehicle wheel of the motor vehicle. It is advantageous if at least the vehicle wheels of one axle comprise a wheel brake according to the invention. In a preferred embodiment of the invention, however, the motor vehicle can also comprise four electromechanically actuated wheel brakes or a wheel brake according to the invention on each vehicle wheel.

The mechanical components associated with the brake unit or actuator, in particular converters, servomotors or actuators and/or gears, can advantageously remain and be arranged close to the wheel of the brake unit, i.e. in the direct vicinity of the vehicle wheel. These can be used in a known manner to act directly or indirectly on at least one associated motor vehicle friction lining via suitable transmission means for the purpose of releasable friction cooperation.

These components can therefore be standardized - at least in part - for several vehicles or vehicle types, i.e. designed to be identical, and the vehicle-specific functions can be made available by means of the control electronics. In other words, the invention means that it is no longer necessary to equip each wheel brake of a vehicle with vehicle-specific software or vehicle-specific mechanical components, such as vehicle-specific actuators, since vehicle-specific functions can be made available by the central control electronics.

The electronic components and switching units required for controlling and regulating the electromechanically actuated wheel brakes can be implemented in one or more microcontrollers in accordance with the invention. The microcontroller(s) can therefore represent a component of the control electronics.

For the sake of simplicity, we will refer to a microcontroller below, whereby this is generally understood to mean a microprocessor together with peripheral functions. However, for the purposes of the invention, a simple microprocessor, possibly even without further peripheral functions, can already be sufficient.

The control electronics can be designed to control the brake unit and/or the actuator, preferably all brake units and/or actuators of the vehicle wheels of an axle or all vehicle wheels of a motor vehicle. For this purpose, the control electronics can be designed to generate corresponding control signals for controlling the brake unit and/or the actuators.

According to a particularly preferred embodiment of the invention, the control electronics can also be configured to process the measured values from the sensors assigned to the wheel brake.

The brake unit and/or the actuator can be controlled by the control signals of the control electronics, preferably electrical or electronic signals. The control electronics, in particular the at least one microcontroller, can therefore generate control signals for electronic motor control of the brake unit and/or the actuator.

At this point, it should be noted that in the context of this application, no distinction is made between the terms "control" and "regulate". The meaning of the corresponding terms arises from the respective context.

In accordance with the invention, it is intended to combine and arrange the microprocessors or microcontrollers typically required for controlling the individual brake control units or their functions at a central location on or in the motor vehicle. The central arrangement and combination of the functions for controlling the wheel brakes can thus enable central signal acquisition and processing.

In other words, the local "intelligence" of the individual brake control units, in particular the microcontrollers of the brake control units and their functionalities, can be moved from the individual wheel brakes to a centrally located microcontroller. This can reduce the number of microcontrollers required. Ideally, most or even all of the functionalities of the individual microcontrollers of the local brake control units are combined in at least one central microcontroller.

The control electronics can therefore be arranged at a distance, in particular spatially and/or structurally separated from the wheel brake. It can advantageously be arranged on or in the vehicle frame.

The invention offers the advantage of saving expensive electronic components, particularly electronic circuits such as microcontrollers, especially with regard to brake control units arranged close to the wheels, so-called “wheel controller units” (WCU), since the local electronic circuits can be significantly reduced or simplified or even dispensed with entirely. This results in a wide range of cost-saving potential.

This spatially centered arrangement also offers the advantage of being able to place the control electronics where there is sufficient installation space and/or where the connection, for example to the vehicle's electrical system or power supply, is conveniently located. At least in the area around the vehicle wheel, installation space can be saved.

According to a preferred embodiment of the invention, the control electronics can be partially or completely implemented in an application-specific integrated circuit (ASIC), so that a so-called “system-on-a-chip” (SOC) can be realized.

According to a further preferred embodiment of the invention, the control electronics can also be partially or completely implemented in a so-called “high performance computer” (HPC) of the motor vehicle, i.e. in a central vehicle computer with high performance.

Combinations are also possible and considered.

In this way, a backup for redundancy can also be provided at low cost by designing the central microcontroller as the main controller and another microcontroller as the backup controller, whereby the range of functions of the backup controller can be further reduced for cost reasons.

For example, special functions such as ABS, ESP and/or ASR functions can be omitted from the backup controller. In this way, in a backup mode, for example if the main controller fails, the backup controller can at least still brake with minimum functions. A diagonal division of the wheel braking functions in relation to the vehicle wheels is also possible and is being considered.

The control electronics can also be integrated into the vehicle's on-board network and/or connected to a vehicle computer.

For signal or data transmission, at least one data line can advantageously be provided between the control electronics and the brake unit, which is designed to transmit the control signals from the control electronics to the brake units.

According to a preferred embodiment of the invention, the wheel brake can further comprise at least one, preferably several sensors arranged close to the wheel or on the wheel brake. This sensor can comprise a current sensor, an angle sensor, a voltage sensor, a temperature sensor, a clamping or spreading force sensor and/or a wheel speed sensor, whereby the following list is not intended to be exhaustive.

These sensors can measure important wheel brake variables, such as the current wheel speed. This information about the current state of the respective wheel brake, also known as sensor signals, can be made available to the control electronics and can therefore be used particularly advantageously for control purposes. A clamping force sensor can, for example, measure the clamping force currently applied to the brake disc, with which a friction lining is pressed against it. In a similar way, a spreading force sensor can measure the force component acting on a drum brake in real time.

The at least one data line of the braking system according to the invention can also be used to transmit the measured values recorded by the at least one sensor as sensor signals to the control electronics during operation. The control electronics can therefore be set up to receive and/or evaluate and process the measured values of the sensors, so that status information of the respective wheel brake can be taken into account when generating the control commands.

According to a preferred embodiment of the invention, the data line provided between the control electronics and the brake unit can therefore be designed such that not only control commands can be transmitted from the control electronics to the respective brake unit, but also that measured values of the sensors, preferably as digital sensor signals, can be transmitted to the control electronics via the at least one data line.

For capacity and time reasons, the control commands and/or the measured values are preferably transmitted as digital signals. For this purpose, the control electronics and/or the brake unit can have at least one corresponding signal converter structure block, in particular an A/D and/or a D/A signal converter module, or corresponding encoders. This makes it possible, for example, to convert analog signals from the sensors into digital signals and to transmit them as digital signals via the data line to the control electronics. According to a further development, it is also possible for the signal converter module to combine measured values from several sensors into corresponding signals so that these can be transmitted in a bundle.

The at least one data line can be designed redundantly and, for example, comprise two structurally separate data lines. If one data line is damaged, the second, redundant data line can then continue to be used. The two redundant data lines preferably have the same functionality.

The transmission of the control signals and the sensor signals via at least one data line can, for example, be carried out alternately unidirectionally.

According to a preferred embodiment of the invention, the data line can be designed to transmit electrical signals and for this purpose can comprise at least one electrical conductor, preferably a multi-core electrical conductor. The multi-core electrical conductor can, for example, be designed as a twisted pair cable, which is inexpensive and available in a wide variety of configurations.

According to a further, likewise preferred embodiment of the invention, the data line can be designed to transmit optical signals and can comprise at least one fiber optic optical waveguide, preferably more than one fiber optic optical waveguide for redundancy. In a particular embodiment, the braking system according to the invention comprises only fiber optic optical waveguides.

This makes it possible, according to a preferred embodiment of the invention, to dispense with copper-containing cables or lines between the control electronics and the brake unit or at least to reduce their use. As resources become scarcer, this can be advantageous, especially since fiber optic light waveguides can also be more cost-effective and data transmission can be even faster.

According to a further embodiment of the invention, it is envisaged to design at least the control electronics with devices for wireless communication. In this way, "over-the-air updates" can be provided, i.e. software updates that are made available via a radio interface. It goes without saying that in such cases the control electronics should have suitable safety functions and be secured accordingly. The invention thus offers the possibility of being able to carry out software updates or vehicle-specific adjustments simply and centrally, even for each individual connected wheel brake.

Of course, wired software updates can also be provided as an alternative or in addition. For this purpose, the control electronics can be integrated into the vehicle's on-board network and have corresponding additional functions.

According to a further preferred embodiment of the invention, the braking system, in particular the braking unit, can comprise at least one memory. Information relevant to the respective wheel brake can be stored in this memory, for example information on the mounted wheel brake, or specific operating information, such as maximum application forces.

This information can be queried by the control electronics, for example at the beginning or cyclically or at other, specified times. This information can also be stored in another memory in the control electronics. This enables the control electronics, for example, to compare information about the wheel brakes stored in the control electronics' memory with information about the wheel brakes that is currently being queried. In this way, it can be detected, for example, that a wheel brake has been replaced, or that an unsuitable wheel brake has been installed, or that wheel brakes were connected incorrectly during a repair and/or that the data lines were swapped around. The information stored in the wheel brake memory or in the control electronics can also be stored in coded or encrypted form. The wheel brake memory and/or the control electronics' memory can advantageously include a partition in which data can be stored in an unchangeable and indelible manner.

The invention makes it possible for only one additional electrical line to be provided between the vehicle frame and the wheel brake according to the invention in addition to the at least one data line to supply voltage to the wheel brake. This significantly reduces the effort and costs.

The braking system according to the invention can be designed as a service brake. However, it can can also be designed as a parking brake or be equipped as a service brake with a parking brake function.

Furthermore, the invention also relates to a motor vehicle comprising a braking system as described above.

Finally, a method for operating a braking system for a motor vehicle is also the subject of the present invention, wherein the method is designed for use with a wheel brake as described above.

Further details of the invention emerge from the description of the illustrated embodiments and the appended claims.

• 1 schematisch eine Ansicht der beispielhaften Radbremse in einem Ausschnitt, und
• 2 schematisch eine mögliche Verschaltung einer beispielhaften Radbremse.

The drawings show:

• 1 schematically a view of the exemplary wheel brake in a detail, and
• 2 schematically shows a possible wiring of an example wheel brake.

In the following detailed description of preferred embodiments, for the sake of clarity, like reference numerals designate substantially like parts in or on those embodiments. However, to better illustrate the invention, the preferred embodiments shown in the figures are not always drawn to scale.

1 shows schematically a section of an exemplary braking system 100 according to the invention based on a top view of a vehicle wheel (not shown) of a motor vehicle. The vehicle is only schematically indicated in the depicted illustration with some important components and shows in the illustration a wheel housing 1 for receiving the vehicle wheel and a section of the vehicle frame 2. Furthermore, a wheel brake 10 with important components is shown schematically.

In the illustrated braking system 100, each wheel brake 10 is assigned at least one braking unit 11, which has at least one electric motor-operated actuator 13 that is designed to generate a braking force.

• - einen Sensor 16 zur Erfassung eines radspezifischen Merkmals,
• - und eine Ansteuerelektronik 20 mit zumindest einem Mikrocontroller 21, ausgebildet zur Erzeugung von Regelsignalen zur Ansteuerung der Bremseinheit 11 und/oder des Aktuators 13,
• - wobei die Ansteuerelektronik 20 beabstandet von der Radbremse 10 angeordnet ist, insbesondere räumlich getrennt von der Radbremse 10 in dem Fahrzeugrahmen 2,
• - wobei zwischen der Ansteuerelektronik 20 und der Bremseinheit 11 zumindest eine Datenleitung 23 vorgesehen ist, welche für die Übertragung der Regelsignale ausgebildet ist, und
• - wobei im Betrieb die durch den zumindest einen Sensor 16 erfassten Messwerte, bevorzugt als digitale Sensorsignale, über die zumindest eine Datenleitung 23 an die Ansteuerelektronik 20 übermittelt werden können.

The braking system 100 further comprises

• - a sensor 16 for detecting a wheel-specific feature,
• - and a control electronics 20 with at least one microcontroller 21, designed to generate control signals for controlling the brake unit 11 and/or the actuator 13,
• - wherein the control electronics 20 are arranged at a distance from the wheel brake 10, in particular spatially separated from the wheel brake 10 in the vehicle frame 2,
• - wherein between the control electronics 20 and the brake unit 11 at least one data line 23 is provided, which is designed for the transmission of the control signals, and
• - wherein during operation the measured values detected by the at least one sensor 16 can be transmitted, preferably as digital sensor signals, via the at least one data line 23 to the control electronics 20.

The motor vehicle comprises at least one axle, preferably two axles, which are equipped with vehicle wheels and respective associated wheel brakes 10. These wheel brakes 10 are designed as electromechanically actuated wheel brakes. In the illustrated embodiment of the 1 The brake unit 11 is designed as an electromechanical disc brake. However, the brake unit 11 can also be designed as an electromechanical drum brake or as a solid disc or multi-disk brake. Other embodiments, such as a wedge brake, are also conceivable.

Typically, a brake actuation unit is also provided, such as an electric brake pedal, which is not shown here for the sake of clarity.

The brake unit 11 has at least one actuator 13, which comprises the necessary converters, servomotors or actuators and/or gears in order to be able to bring about a braking effect by applying pressure to a motor vehicle friction lining when activated. In the exemplary embodiment, the wheel brake 10 is equipped with two friction linings 14 and a brake disk 15 for this purpose.

At least the components brake unit 11, actuator 13, converter, servomotor and/or transmission can be standardized by the invention in whole or in essential parts for several vehicles or vehicle variants, i.e. they can be designed at least largely or ideally identically. The vehicle-specific functions can be made available by means of the control electronics 20.

This offers significant cost advantages compared to wheel brakes, which each comprise a local brake control unit on each vehicle wheel. It is no longer necessary to equip each wheel brake of a vehicle with vehicle-specific software and/or vehicle-specific hardware, for example, vehicle-specific actuators 13, since many, preferably all, vehicle-specific functions can be made available by the central control electronics 20.

According to the invention, the electronic components and switching units required for control and regulation, which are typically implemented in one or more microcontrollers, are combined in the central control electronics 20. The control electronics 20 are therefore designed to control the brake unit 11 and/or the actuator 13, preferably all electromechanical brake units 11 and/or electromechanical actuators 13 of the motor vehicle.

The brake unit 11 and/or the actuator 13 are controlled by electrical or electronic signals. The control electronics 20, in particular the at least one microcontroller 21, is designed to generate corresponding control commands.

The control electronics 20 are also set up to process the measured values of the sensors 16, which are assigned to the wheel brakes 10. The central arrangement of the microcontroller 21 thus enables central signal acquisition and processing.

The “intelligence” of the otherwise frequently used local brake control units, in particular the microcontrollers of the brake control units and their functionalities, is thus shifted from the individual wheel brakes to the centrally arranged microcontroller 21.

This allows the number of microcontrollers required to be significantly reduced. Ideally, most or even all of the functions of the individual microcontrollers of the local brake control units are combined in a central microcontroller 21. Ideally, the wheel brakes 10 therefore no longer include any microcontrollers, since the control electronics 20 are arranged spatially separate from the wheel brake at a central location in the vehicle. The braking system 100 can therefore be implemented with just a single microcontroller 21.

In the present case, the control electronics 20 are completely implemented in an application-specific integrated circuit (ASIC), so that a so-called “system-on-a-chip” (SOC) is realized.

According to another embodiment of the invention, the control electronics 20 can also be partially or completely implemented in a so-called “high performance computer” (HPC) of the motor vehicle.

According to a preferred development of the invention, a backup is provided in which the microcontroller 21 is designed as the main controller and a further microcontroller is provided as the backup controller 21a, wherein the functional scope of the backup controller 21a is reduced for cost reasons.

The backup controller 21a may not include ABS, ESP and/or ASR functions, but only the functions that are at least required for braking. In this way, braking with minimum functions can still be enabled, even in a backup mode.

The in 1 The wheel brake 10 shown further comprises sensors 16 arranged close to the wheel or on the wheel brake 10, whereby only one sensor 16 is shown for the sake of clarity. This sensor 16 can comprise a current sensor, an angle sensor, a voltage sensor, a temperature sensor, a clamping or spreading force sensor and/or a wheel speed sensor, whereby the following list is not intended to be exhaustive. In the present embodiment, it is a wheel speed sensor.

The control electronics 20 are designed to receive and/or evaluate and process the measured values and information from the sensors so that status information of the respective wheel brake can be taken into account in real time to generate the control commands.

For this purpose, the wheel brake 10 comprises a data line 23, which is designed to transmit the control commands from the control electronics 20 to the respective brake unit 11 and to transmit information from the sensors 16 to the control electronics 20.

The brake unit 11 comprises at least one signal converter module 12, which is designed to convert analog measured values or signals from the sensor 16 into digital sensor signals so that they can be transmitted easily and quickly via the data line 23, 23a. The control electronics 20 can also comprise a signal converter module 22.

In the embodiment, the control signals and the sensor signals are transmitted alternately unidirectionally via the data line 23, 23a. However, other transmission methods are also possible. possible and planned, for example bidirectional data transmission.

In the illustrated embodiment of the 1 the data line 23 is designed redundantly and includes a further, structurally separate data line 23a. This provides the same functionality as the data line 23.

The data line 23, 23a is designed to transmit electrical signals and can comprise at least one electrical conductor, preferably a multi-core electrical conductor. The data line 23, 23a can comprise a twisted pair cable, for example.

According to a further embodiment of the invention, the data line 23, 23a is designed to transmit optical signals and for this purpose comprises at least one fiber-optic light waveguide. Two separate fiber-optic light waveguides can also be provided for redundancy. In the 1 Further data lines 23, 23a are indicated. These can lead to other wheel brakes 10 not shown here.

In the exemplary embodiment, the control electronics 20 are designed with devices 25 for wireless communication. In this way, “over-the-air updates” can be provided.

In addition, in the embodiment of the 1 A connection to the vehicle's on-board network is also provided, which is to be made clear by the data line 24.

In the brake system 100 shown, the brake unit 11 comprises at least one memory 17. Information relevant to the respective wheel brake 10 can be stored in this memory 17, for example information on the type of wheel brake installed, or specific operating information, such as maximum clamping forces. This information can be queried by the control electronics 20, for example at the beginning or cyclically or at other, otherwise specified times. This information can also be stored in another memory 26 of the control electronics 20.

This enables the control electronics 20, for example, to compare information about the wheel brakes 10 stored in the memory 26 of the control electronics 20 with information about the wheel brakes 10 that is currently being queried. In this way, it can be recognized, for example, that a wheel brake 10 has been replaced, or that an unsuitable wheel brake 10 has been installed, or that wheel brakes 10 have been connected incorrectly during a repair and/or that the data lines 23, 23a have been swapped. The information stored in the memory 17 of the wheel brake 10 or in the control electronics 20 is stored in coded or encrypted form for this purpose. The memory 17 of the wheel brake 10 and/or the memory 26 of the control electronics 20 comprises a partition in which data can be stored in an unchangeable and indelible manner.

The invention makes it possible for only one further electrical line 27 to be provided between the vehicle frame 2 and the wheel brake 10 in addition to the at least one data line 23, 23a for supplying voltage to the wheel brake 10. This significantly reduces the effort and costs for the wiring.

2 shows schematically a possible wiring arrangement of an exemplary wheel brake 10 with a local brake control unit 30 for illustration purposes. The wheel brake 10 comprises a motor 32, which is designed, for example, as an electric motor and can be used to build up hydraulic pressure in a brake system. The motor 32 is connected to the power supply of the motor vehicle via a B6 bridge 31. The local brake control unit 30 comprises in particular only the units that are absolutely necessary for direct control, such as A/D converters (ADC) or pulse width modulation (PWM) and for local voltage supply.

The invention also relates to a motor vehicle which has at least one braking system 100 as described above.

Finally, a method for operating a braking system 100 for a motor vehicle is also the subject of the present invention, wherein the method is designed to use electromechanically actuated wheel brakes 10 as described above.

• - Erfassen eines Fahrer-Bremswunsches einer Betätigungseinheit,
• - Übermitteln einer hierauf basierenden Bremsanforderung an die Ansteuerelektronik 20,
• - Übermitteln von Informationen zum Betriebszustand der Radbremse 10, insbesondere Sensorsignale der Radsensoren 16, vorzugsweise in Echtzeit, an die Ansteuerelektronik 20,
• - Erzeugen von Regelsignalen für ein aufzubringendes Bremsmoment oder eine Bremskraft für die Radbremsen 10 auf Basis der Bremsanforderung und der Sensorsignale,
• - Übermitteln der Regelsignale über die Datenleitung 23, 23a an die lokale Bremseinheit 11 bzw. den lokalen Aktuator 13 zur Umsetzung der Bremsanforderung.

The procedure includes the following steps in operation:

• - Detecting a driver braking request of an actuating unit,
• - Transmitting a braking request based thereon to the control electronics 20,
• - transmitting information on the operating state of the wheel brake 10, in particular sensor signals from the wheel sensors 16, preferably in real time, to the control electronics 20,
• - generating control signals for a braking torque or a braking force to be applied to the wheel brakes 10 based on the braking request and the sensor signals,
• - Transmitting the control signals via the data line 23, 23a to the local braking unit 11 or the local actuator 13 to implement the braking request.

List of reference symbols:

1

wheel arch

2

vehicle frame

10

wheel brake

11

brake unit

12

signal converter module

13

actuator

14

friction lining

15

brake disc

16

sensor

17

storage

20

electronic unit

21

microprocessor

21a

backup controller

22

signal converter module

23, 23a

data line

24

data line

25

wireless communication device

26

memory

27

power supply cable

28

mass

30

local brake control unit

31

B6 bridge

32

Motor

QUOTES INCLUDED IN THE DESCRIPTION

This list of documents listed by the applicant was generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA accepts no liability for any errors or omissions.

Cited patent literature

• DE 102016221189 A1 [0005]

Claims (17)

Braking system (100) comprising at least two electromechanically actuated wheel brakes (10) as part of a service brake of a motor vehicle, which are connected to a vehicle frame (2), wherein - each wheel brake (10) is assigned at least one brake unit (11), which has at least one actuator (13) operable by an electric motor, which is designed to generate a braking force, further comprising - at least one sensor (16) designed to detect a wheel-specific feature, - and at least one control electronics (20) with at least one microcontroller (21) designed to generate control signals for controlling the brake unit (11) and/or the actuators (13), - wherein the control electronics (20) are arranged at a distance from the wheel brake (10), in particular spatially separated from the wheel brake (10) in the vehicle frame (2), - wherein at least one data line (23) is provided between the control electronics (20) and the brake unit (11), which is designed for the transmission of the control signals, and - wherein during operation the measured values recorded by the at least one sensor (16), preferably as digital sensor signals, can be transmitted to the control electronics (20) via this at least one data line (23). Braking system (100) according to the preceding claim, characterized in that the braking unit (11) is designed as an electromechanical disc brake, as an electromechanical drum brake and/or as an electromechanical multi-disk brake. Braking system (100) according to one of the preceding claims, characterized in that all vehicle wheels of the motor vehicle comprise electromechanically actuated wheel brakes (10) which can be controlled during operation by the control signals of the control electronics (20). Braking system (100) according to one of the preceding claims, characterized in that the control electronics (20) are implemented in a central, application-specific integrated circuit (ASIC) or in a high-performance computer (HPC) of the motor vehicle. Braking system (100) according to one of the preceding claims, characterized in that the microcontroller (21) comprises a main controller (21a) and a backup controller (21b), wherein the backup controller (21b) in particular has a reduced range of functions compared to the main controller (21a). Braking system (100) according to one of the preceding claims, characterized in that the sensor (16) comprises a wheel speed sensor, a current sensor, an angle sensor, a voltage sensor, a temperature sensor, and/or a clamping or spreading force sensor. Braking system (100) according to one of the preceding claims, characterized in that the braking unit (11) preferably comprises at least one signal converter module (12) which is designed to convert analog signals of the at least one sensor (16) into digital signals. Braking system (100) according to one of the preceding claims, characterized in that the at least one data line (23) is designed redundantly with two structurally separate data lines (23a, 23b), preferably with the same functionality. Braking system (100) according to one of the preceding claims, characterized in that the transmission of the control signals and the sensor signals via the at least one data line (23) takes place alternately unidirectionally. Braking system (100) according to one of the preceding claims, characterized in that the data line (23) is designed to transmit electrical signals and comprises at least one electrical conductor, preferably a multi-core electrical conductor and particularly preferably a twisted pair cable. Braking system (100) according to one of the preceding claims, characterized in that the data line (23) is designed to transmit optical signals and comprises at least one fiber optic optical waveguide, preferably more than one fiber optic optical waveguide and particularly preferably only fiber optic optical waveguide. Braking system (100) according to one of the preceding claims, characterized in that the control electronics (20) have devices for wireless communication. Braking system (100) according to one of the preceding claims, characterized in that the braking unit (11) and/or the control electronics (20) comprise at least one memory or partition in which information or operating information relevant to the respective wheel brake can be stored. Braking system (100) according to the preceding claim, characterized in that the information or operating information relevant to the respective wheel brake can be stored in an unchangeable and indelible manner. Braking system (100) according to one of the preceding claims, characterized in that between the vehicle frame (2) and the wheel brake (10), in addition to the data line (23), only one further electrical line for supplying voltage to the wheel brake (10) is provided. Braking system (100) according to one of the preceding claims, characterized in that the control electronics (20) are integrated into the on-board network of the vehicle and/or are connected to a vehicle computer. Method for operating a braking system (100) for a motor vehicle, wherein the method runs on a braking system (100) according to one of the preceding claims.

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