Electromechanical brake system for motor vehicle and method for operating electromechanical brake system in motor vehicle

Abstract

The invention relates to a method for operating an electromechanical brake system (110) in a motor vehicle, the brake system (110) having at least one input unit (113, 114) via which a brake demand is transmitted, and at least two brake devices (1, BU), each comprising a brake actuator (4, BM) having at least one electric actuating motor (41, 42), the brake devices (1, BU) are each assigned a wheel brake control unit (120, BC) and a wheel speed sensor unit (121), the associated wheel speed sensor unit (121) of the associated wheel brake control unit (120, BC) providing a wheel speed (P2) for the respective brake device (1, BU), and the associated wheel speed sensor unit (121) of the associated wheel brake control unit (120, BC) providing a wheel speed (P2) for the respective brake device (1, BU). An alternative wheel speed (EP1) for a wheel speed (P2) provided by an associated wheel speed sensor unit (121) is provided to the wheel brake control unit (120, BC), where the wheel brake control unit (120, BC) actuates the brake actuator (4, BM) in normal operation taking into account the wheel speed (P2) provided by the associated wheel speed sensor unit (121), and the brake actuator (4, BM) actuates the wheel brake control unit (120, BC) in normal operation taking into account the wheel speed (P2) provided by the associated wheel speed sensor unit (121). The brake actuator (4, BM) is actuated by the associated wheel speed sensor unit (121) in order to achieve the transmitted brake demand, and the wheel brake control unit (120, BC) actuates the brake actuator (4, BM) taking into account the provided alternative wheel speed (EP1) in order to achieve the transmitted brake demand in the event of an interruption in providing the wheel speed (P2) by the associated wheel speed sensor unit (121). Furthermore, the invention relates to a brake system (110) which is particularly configured to operate according to a method of this type.

Description

Technical Field

[0001] This invention relates to an electromechanical braking system for a motor vehicle, the system comprising at least one input device for transmitting braking demand and at least two braking devices, each of the at least two braking devices having a wheel speed sensor unit configured to provide wheel speed to the associated braking device, wherein each braking device includes a brake actuator having at least one electric actuation motor. Furthermore, this invention relates to a method for operating an electromechanical braking system in a motor vehicle, wherein the braking system comprises: at least one input unit for transmitting braking demand; and at least two braking devices, each of the at least two braking devices including a brake actuator having at least one electric actuation motor. Background Technology

[0002] This type of braking system includes at least two electric motor braking devices, each assigned to a wheel of a motor vehicle to be braked. Therefore, it is also referred to as a braking unit or wheel brake. One electric motor braking device has an electric motor brake actuator supported on the chassis of a motor vehicle for rotation relative to the wheel to be braked, and it has at least one electric actuating motor. The latter acts via an actuating device on a braking component, such as a brake pad, which can be driven by the rotation of the actuating motor to engage with a reverse braking component, such as a brake disc, attached to the wheel to be braked. During braking engagement, frictional contact is generated between the braking component and the reverse braking component, wherein the braking torque generated by friction increases with increasing adjusting force applied by the actuating device in the adjusting direction. This type of braking system is known in the prior art, for example from DE 10 2017 123 266A1, US 6,397,981B1, or US 6,081,081A. According to the disclosure in US 6,081,081A, each brake actuator can be actuated individually by the central control unit. Therefore, each braking device can be activated individually to optimize braking action.

[0003] The braking system is electrically actuated. Braking demands, particularly electric braking commands, for initiating braking operations can be manually generated by an input unit, specifically the brake pedal or parking brake switch. Alternatively, they can be manually generated by an automatic input unit, particularly the anti-lock braking system (ABS) or automatic driving system (ADS). To accommodate this type of braking demand, the actuation motor of the brake actuator can be actuated, and the braking device can be engaged.

[0004] The optimal braking torque can be determined based on a setpoint output by the braking demand and other practical parameters related to the braking operation, particularly wheel position, wheel speed, actuation motor current, braking force, vehicle speed, and / or other practical parameters. This optimal braking torque allows for the shortest possible braking distance without locking the wheels. For example, in the prior art, values ​​for braking demand, along with other values ​​that may be provided to a central control unit (ECU), are known from US 6,317,675B1. This ECU determines the required control current for the actuation motors of all brake actuators and the current required to generate the determined wheel braking torque, according to a predefined control algorithm. Here, wheel speed is a practical parameter with specific meaning and should always be provided to translate the braking demand into corresponding braking engagement of the appropriate braking equipment, thereby preventing brake failure, or even partial brake failure. To improve reliability, US 6,410,993B1 discloses a circuit device with a dual-circuit or multi-circuit structure for safety-critical control systems, such as brake-by-wire systems, wherein each circuit of the circuit device includes a complete microprocessor system that processes input data in a redundant manner and supplies a fault identification signal (FAIL) in the event of a fault or a discrepancy between the redundantly generated data processing results. Summary of the Invention

[0005] In this context, the object of the present invention is to provide an improved electromechanical braking system and an improved method for operating the electromechanical braking system, wherein reliability is advantageously improved, and in particular, the reliability of providing wheel speed is improved in a cost-effective manner.

[0006] To achieve this objective, a method for operating an electromechanical braking system in a motor vehicle and an electromechanical braking system, as claimed in the independent claims, are proposed. Further advantageous improvements of the invention are described in the dependent claims and the description, and are illustrated in the accompanying drawings.

[0007] The proposed solution provides a method for operating an electromechanical braking system in a motor vehicle, wherein the braking system has at least one input unit via which braking demand is transmitted; and at least two braking devices, each comprising a brake actuator with at least one electric actuation motor, wherein each braking device is assigned a wheel brake control unit and a wheel speed sensor unit. The relevant wheel speed sensor unit of the relevant wheel brake control unit provides wheel speeds to the corresponding braking devices, and a substitute wheel speed provided by the relevant wheel speed sensor unit is provided to the wheel brake control unit. According to the invention, in normal operation, the wheel brake control unit actuates the brake actuator to fulfill the transmitted braking demand, taking into account the wheel speed provided by the relevant wheel speed sensor unit; and in the event of an interruption in the wheel speed provided by the relevant wheel speed sensor unit, the wheel brake control unit actuates the brake actuator by taking into account the provided substitute wheel speed. Specifically, the substitute wheel speed is not determined by the wheel speed sensor unit assigned to the relevant wheel, and preferably not by redundant wheel speed sensor units having the same configuration and assigned to the relevant wheel. In this regard, while the alternative wheel speed is specifically a parameter approximating the actual wheel speed, and particularly can be consistent with the actual wheel speed, some deviation from the actual wheel speed is certainly acceptable, especially deviations related to the actual wheel speed. Therefore, by advantageously using the alternative wheel speed of the relevant wheel instead of the wheel speed of the relevant wheel as a parameter in the event of an interruption, it is advantageous to further control the brake actuator, particularly with respect to the corresponding control algorithm without deviating from normal operation. Here, according to an improvement, the alternative wheel speed is only provided in the event of an interruption. However, it is specifically stipulated that even in normal operation without interruption, an alternative wheel speed must be determined and provided for each wheel. Further advantageously, by utilizing the alternative wheel speed in normal operation, the wheel speeds provided by the relevant wheel speed sensor units are diagnosed, particularly for reasonableness checks. In this way, problems related to determining one of the wheel speed sensor units and / or to the alternative wheel speed can be advantageously detected at an early stage.

[0008] According to an advantageous improvement, the wheel brake control units are interconnected via a data transmission system, particularly a communication bus, and further particularly a CAN bus, for exchanging data. The wheel speeds are advantageously provided via the data transmission system to the wheel brake control unit assigned to the brake device by at least one of the wheel speed sensor units not assigned to the brake device as alternative wheel speeds. In this case, the alternative wheel speeds are wheel speeds measured at different wheels. In the case of a four-wheeled motor vehicle, in this respect, the wheel speeds of the other wheels are specifically provided as alternative wheel speeds to the first brake device assigned to the wheels. Here, in particular, the processing and weighting of the three wheel speeds of the other three wheels are also provided in a manner dependent on current driving parameters, wherein the calculated alternative wheel speeds are determined based on the three wheel speeds detected by the sensors of the first brake device. Thus, in this improvement, by detecting the wheel speeds of the other wheels of the motor vehicle, the failure of the sensors to detect the wheel speed of the first wheel is advantageously compensated for.

[0009] Another advantageous improvement specifies that the input unit of the braking system is connected to the corresponding wheel brake control unit via a communication link to transmit braking requirements. Here, the wheel speed provided by one of the other wheel brake control units is used as a substitute wheel speed and provided via the communication link to the wheel brake control unit assigned to the braking device. The communication link between the input unit of the braking system and the wheel brake control unit is advantageously not implemented via a communication bus. This ensures that, particularly in the event of an interruption to the communication bus preventing the other wheel brake control units from providing wheel speeds to the first wheel brake control unit via the communication bus, the wheel speed can still be provided via this communication link as a substitute wheel speed. Specifically, the communication link between the input unit and the corresponding wheel brake control unit is a line cable, preferably a sensor cable.

[0010] Advantageously, braking demand is transmitted via a communication link in a first frequency range, and alternative wheel speed is transmitted via the communication link in a second frequency range, which is different from the first frequency range. Specifically, the first frequency range is in the range of 1 kHz, and the second frequency range is in the range of 100 kHz. In particular, the first and second frequency ranges are significantly different from each other, so that the braking demand signal and the alternative wheel speed signal do not interfere with each other. The braking demand is preferably transmitted as a first signal to the wheel brake control unit via the communication link, and the alternative wheel speed is transmitted as a second signal modulated onto the first signal via the communication link, wherein the first signal is transmitted specifically in the first frequency range, and the second signal is transmitted specifically in the second frequency range. The corresponding wheel brake control unit providing the alternative wheel speed advantageously modulates the alternative wheel speed into a second signal, and the corresponding wheel brake control unit demodulates the second signal. Further advantageously, the input unit of the braking system is a brake pedal or brake pedal sensor, which is included within the brake pedal and transmits the brake pedal position as a braking demand in an analog or digital manner. The wheel speed, as a second signal, is transmitted specifically via a sensor cable serving as a communication link, leading from the brake pedal sensor to the wheel brake control unit. In this regard, each wheel brake control unit advantageously has a current link to the input unit, particularly to the brake pedal sensor. The brake pedal sensor preferably automatically transmits information about the braking demand via the pedal position. The brake pedal sensor can be an analog or digital sensor. Here, each wheel brake control unit preferably has a receiver interface that receives the braking demand from the brake pedal sensor as a first signal. Furthermore, the receiver interface is advantageously configured to feed the signal into the communication link, which can be formed, particularly by the pedal sensor line, and preferably by modulation. The wheel brake control unit can advantageously exchange information with other control units by means of this modulation, and thus can transmit wheel speed, in particular. In cases where the wheel brake control unit fails to receive any information about the current wheel speed from the associated wheel speed sensor, for example due to a defect in the cable or sensor, the wheel brake control unit can advantageously query other wheel brake control units for their wheel speeds via a data transmission system, which can be specifically configured as a CAN bus and can receive wheel speeds provided as alternative wheel speeds. Alternatively, the wheel brake control unit can advantageously receive signals via a communication link, particularly the cable of the brake pedal sensor, and can decode the modulated signals from other wheel brake control units to obtain alternative wheel speeds.In this respect, even in the event of an interruption in the data transmission system, an alternative wheel speed can be advantageously provided to the wheel brake control unit via the communication link between the wheel brake control unit and the input unit.

[0011] According to another advantageous improvement, at least one braking device in the braking system includes a brake disc, wherein a wheel brake control unit assigned to this type of braking system with a brake disc determines an alternative wheel speed or another alternative wheel speed based on vibrations of the brake disc. Specifically, according to this improvement, an alternative wheel speed is determined for the relevant wheel as a supplement or substitute, wherein the alternative wheel speed is not determined by one of the wheel speed sensor units in the wheel speed sensor unit. Instead, the fact that the speed of the relevant wheel can be inferred via vibrations of the brake disc is advantageously utilized.

[0012] Here, the wheel brake control unit assigned to the braking device with brake discs advantageously detects the ripple current caused by the mechanical connection in at least one actuating motor of the braking device, and determines an alternative wheel speed or another alternative wheel speed based on the detected ripple current. This is advantageously made possible by the fact that the small gap between the brake disc and brake pads couples the mechanical motion to the actuating motor, particularly via the brake pads, brake piston, slider, motor shaft, motor, and the current generated in the motor. This vibration causes ripple in the motor current, i.e., it results in ripple current. Since the wheel brake control unit assigned to the actuating motor specifically measures the motor current, it is advantageously specified that the wheel brake control unit measures and evaluates the ripple coefficient of the current. The wheel speed is advantageously estimated by the wheel brake control unit based on the ripple frequency.

[0013] A further advantageous provision is that, during normal operation, the artificial intelligence (AI) system, particularly the AI ​​system of the wheel brake control unit or the AI ​​system of the higher-level vehicle control unit, considers the wheel speed provided by the wheel speed sensor unit assigned to the braking device and trains the determination of a substitute wheel speed or another substitute wheel speed based on the ripple current detected for the braking device. This advantageously improves the assignment of vibration to the wheel speed. In this way, the substitute wheel speed advantageously approximates the actual wheel speed in an improved manner.

[0014] Another advantageous improvement to this method specifies that the braking device is connected to a central control unit, which is configured to be connected to at least one input unit. Braking demand is input to the central control unit from at least one of the input units. The central control unit actuates the brake actuators via control signals. The central control unit outputs control signals to at least two wheel brake control units, each of which is assigned to the braking device and actuates the brake actuator of its respective device. One advantage of this configuration is that higher reliability can be achieved through a distributed control architecture, particularly through a robust implementation less sensitive to external disturbances, and the possibility of redundantly distributing control functions to the central control unit and the wheel brake control units. Specifically, the anti-lock braking system (ABS) control operation can be performed distributed and independently of the central control unit via the wheel brake control units and associated wheel speed sensor units. Therefore, further improved reliability can be achieved.

[0015] Advantageously, the actual signal is transmitted from the wheel speed sensor unit of the corresponding braking device to each wheel brake control unit in the wheel brake control unit. According to control specifications, taking into account the actual signal from the wheel speed sensor unit, such as, in particular, wheel position and / or wheel speed, the actuation of the corresponding brake actuator is adjusted in the corresponding wheel brake control unit to achieve the set value predetermined by the braking command. The wheel speed sensor unit preferably provides the actual signal of the measured parameters in real time. Actual values ​​provided by other sensor devices, particularly the current of the actuation motor, braking force, and / or vehicle speed, can also be considered and processed. Another advantage of this method is that the processing of the signal supplied by the wheel speed sensor (wheel position sensor) can be performed almost in real time in the distributed wheel brake control units of the braking device. Therefore, improved processing speed and reliability, as well as redundant controller design, can be achieved.

[0016] Furthermore, according to an advantageous improvement, the braking device has an actuating device that can be coupled to at least one actuating motor and includes a first actuating driver and a second actuating driver, the second actuating driver being connected in series with the first actuating driver and acting on a braking component that can engage with a reverse braking component in the axial direction for braking purposes. The first actuating driver has a rotatably driven first drive wheel to which a first driving torque can be applied for actuation, and the second actuating driver has a rotatably driven second drive wheel coaxial with the first drive wheel and to which a second driving torque can be applied for actuation. A clutch device is arranged between the first and second drive wheels. The clutch device is preferably configured as a friction clutch and has a predetermined clutch torque. When this torque is exceeded, the first drive wheel slides relative to the second drive wheel in a sliding manner. The first and second drive wheels are driven synchronously to actuate the first actuation actuator, resulting in the second actuation actuator remaining unacted. To actuate the second actuation actuator, the second drive wheel is driven while the first drive wheel is stationary relative to it, resulting in the friction clutch slipping and the first actuation actuator remaining unacted. To adjust the first actuation actuator, the actuation torque can be coupled to the first drive wheel by means of a first electric actuation motor, and the second actuation actuator can be correspondingly driven by a second electric actuation motor.

[0017] During normal braking operation, the first and second drive wheels advantageously rotate synchronously. This can be achieved firstly by the fact that the first and second drive wheels are driven by a first and a second actuating motor with synchronized drive torque. Secondly, during the driving of the first drive wheel, the second drive wheel can be synchronously driven by the clutch device as long as the transmitted drive torque remains below the clutch torque. In this operating mode, the second actuating actuator advantageously remains unacted and rotates as a whole with the braking element in a free-running manner. In this design variant with a friction clutch, the clutch device can slide continuously and uniformly beyond the clutch torque to adjust the air gap between the braking element and the reverse braking element. This can be achieved in particular by the fact that the drive wheel of the first actuating actuator is fixed, particularly by the corresponding actuation of the brake or the first drive motor, while a second drive torque, greater than the clutch torque, is applied to the second drive wheel by the second drive motor. Therefore, the second drive wheel rotates relative to the first drive wheel, and the air gap can be continuously and precisely adjusted by actuating the second actuating actuator, resulting in optimal compensation for the continuous premature wear of the braking element or brake pads.

[0018] Advantageously, the first and second drive wheels are connected via a friction clutch in a torque-transmitting manner to generate synchronized drive. There is no need to synchronously drive the two drive wheels via an actuation motor. Any potential torque differences can be compensated for within predefined tolerances.

[0019] Advantageously, the clutch torque can be predetermined to be higher during the actuation of the first actuating drive than during the actuation of the second actuating drive. The first actuating drive is actuated by the synchronous drive of the first and second drive wheels. Friction elements and counter-friction elements are preloaded by the spring force of the spring elements against each other, and the adjusting force of the first actuating drive also acts in opposition to the spring force. The result is a relatively high clutch torque. Conversely, if only the second drive wheel is rotated for adjusting the air gap, only the spring force is active, resulting in a lower clutch torque. Air gap adjustment is thus facilitated.

[0020] A braking system for a motor vehicle, as described below, for achieving the objectives stated at the beginning, comprises at least one input device for transmitting braking demand, at least two braking devices, each equipped with a wheel speed sensor unit configured to provide wheel speeds to the associated braking device, wherein each braking device includes a brake actuator having at least one electric actuation motor. Each braking device is also equipped with a wheel brake control unit for controlling the corresponding brake actuator, wherein the wheel brake control unit is configured to control the brake actuator considering the wheel speeds provided by the associated wheel speed sensor unit, and further configured to control the brake actuator considering alternative wheel speeds provided by the associated wheel speed sensor unit. In this respect, control operation can advantageously continue even if the provision of wheel speeds is interrupted, specifically by using their alternative wheel speeds instead of the wheel speeds themselves. In this way, reliability is improved in a cost-effective manner. The braking system is particularly advantageously configured to operate according to the method configured according to the invention.

[0021] Another advantageous improvement to the braking system is that the braking device is connected to a central control unit configured to be connected to at least one input unit, and the wheel brake control unit is connected to the central control unit.

[0022] Braking devices, also synonymously referred to as wheel brakes, are assigned to one wheel of a vehicle in their respective cases. Each braking device has a brake actuator with at least one electric actuation motor, which can apply an adjusting force to the braking components, particularly the brake pads, via an actuation device. Thus, the braking components can engage with the reverse braking components assigned to the wheel, particularly the brake disc. The braking devices can be activated by an input unit, which can have a manual input device such as a brake pedal or parking brake switch, and additionally or alternatively, may have an automatic input unit, such as an anti-lock braking system (ABS) or an automatic driving system (ADS). The input unit is advantageously electrically connected to a central control unit. The central control unit is specifically configured as an ECU (Electronic Control Unit).

[0023] The braking system advantageously has at least two wheel brake control units separate from the central control unit. The wheel brake control units can be electrically actuated by the central control unit via control signals. Since at least two wheel brake control units are provided, each wheel brake control unit is assigned to a braking device and connected to a brake actuator; in other words, it is specified that at least two braking devices each have a dedicated wheel brake control unit connected to both the central control unit and the brake actuator.

[0024] Each wheel brake control unit can be actuated by a central control unit via a setpoint brake value generated from a brake command received from an input device. A decentralized brake control system is achieved through an advantageous combination of a central control unit and at least two distributed wheel brake control units assigned to each wheel. This allows for simpler and shorter wiring, particularly from wheel sensors, especially wheel position sensors and wheel speed sensors assigned to a wheel and directly connected to the wheel brake control unit of the braking device also assigned to that wheel. Consequently, manufacturing and assembly complexity can be advantageously reduced. Furthermore, sensitivity to external interference factors can be reduced. Moreover, the centralized configuration of the brake control system allows for high redundancy, resulting in further improved reliability.

[0025] Here, the wheel brake control unit can preferably be integrated with the braking device. This allows for a compact, reliable, and easy-to-assemble configuration. Each braking device in the braking system preferably has a wheel brake control unit; for example, in the case of a four-wheeled vehicle with four braking devices, four wheel brake control units can be correspondingly provided, or in the case of a two-wheeled vehicle with two braking devices, two wheel brake control units can be correspondingly provided.

[0026] Preferably, the wheel brake control unit is connected to at least one brake actuator in each case. The wheel brake control unit ensures the actuation of the brake actuator by means of a defined setpoint control signal, so as to generate a defined braking torque for the wheel assigned to the corresponding braking device.

[0027] Advantageously, each wheel brake control unit in the wheel brake control unit is connected to an electric actuation motor. The wheel brake control unit can actuate the actuation motor by controlling the electrical setpoint value of the control current. Two or more actuation motors of the braking device can also be connected to a single wheel brake control unit.

[0028] Specifically, each wheel brake control unit is connected to a sensor device. The sensor device preferably includes wheel sensors, particularly wheel speed sensor units, which are assigned to the corresponding wheel to be braked. This can be configured to detect relevant parameters (actual values), particularly wheel position, wheel speed, vehicle speed, and / or slippage, and forward these parameters to the wheel brake control unit. Additionally, sensor devices can be provided for detecting current to the actuation motor, braking force, etc. Each braking device in the braking system preferably has a sensor device, preferably at least one wheel sensor, particularly a wheel speed sensor unit. One advantage is that the sensor units, particularly the wheel speed sensor units assigned to the corresponding braking units, can be connected with relatively low complexity. Since the relevant parameters can be measured at the wheel to be braked and forwarded to the wheel brake control unit without the need for a central control unit, reliability and redundancy can be improved.

[0029] It can be specified that each wheel brake control unit has an adjustment unit. The electric adjustment unit advantageously compares the actual value of the wheel sensor or another sensor device with the setpoint value of the braking demand transmitted from the central control unit to the wheel brake control unit, and accordingly actuates the actuation motor or multiple actuation motors of the brake actuator to achieve these setpoint values.

[0030] According to a further advantageous improvement of the braking system, the braking device includes an actuating device and a braking component connected to the actuating device, the braking component being adjustable along an axis by the actuating device and capable of braking engagement with a reverse braking component, wherein the actuating device has a first actuating driver and a second actuating driver connected in series to the first actuating driver, wherein the first actuating driver has a rotatably driven first drive wheel, and the second actuating driver has a rotatably driven second drive wheel coaxial with the first drive wheel, wherein a clutch device is arranged between the first drive wheel and the second drive wheel, wherein the clutch device is preferably configured as a friction clutch having a friction element that can be connected to a reverse friction element in a frictionally locked manner during clutch engagement. Attached Figure Description

[0031] Other advantageous details, features, and implementation details of the invention will be explained in more detail with reference to the exemplary embodiments shown in the accompanying drawings, in which:

[0032] Figure 1 An exemplary embodiment of a braking system of a motor vehicle configured according to the present invention is illustrated schematically.

[0033] Figure 2a A schematic diagram of another exemplary embodiment of a braking system configured according to the present invention is shown in normal operation.

[0034] Figure 2b It shows the situation in the event of an interruption. Figure 2a A schematic diagram of an exemplary embodiment of a braking system configured according to the present invention.

[0035] Figure 3 A schematic perspective view of an exemplary embodiment of a braking device of a braking system configured according to the present invention is shown.

[0036] Figure 4 It shows according to Figure 3 Side view of the braking device.

[0037] Figure 5 It shows crossing according to Figure 3 The cross-section QQ of the braking device,

[0038] Figure 6 A schematic perspective view is shown according to Figure 3 The first actuation drive of the braking device, and

[0039] Figure 7 Showing from Figure 5 Enlarged detailed drawing of the actuation device.

[0040] In different diagrams, the same parts often have the same name, so sometimes only one diagram is used for explanation in each case. Detailed Implementation

[0041] Figure 1 A schematic, exposed perspective partial view of a chassis 100 of a motor vehicle is shown. The chassis 100 includes steerable wheels 101 mounted on a frame portion of the vehicle body 102, located on a pivotable steering knuckle 103. In this exemplary embodiment, the vehicle's steering system includes a steering shaft 104, to which a steering wheel 105 is attached as a manual steering input device to the rear end (in the direction of travel). The steering shaft 104 is connected to a steering gear 106, which is connected to the steering knuckle 103 via a tie rod 107 to generate steering motion.

[0042] In this exemplary embodiment, the electromechanical braking system 110 of the motor vehicle has a brake pedal 113 attached to the vehicle body 102 and having an associated brake pedal sensor, wherein the brake pedal 113 is a manual input unit for transmitting braking demand. The brake pedal 113 is only used when... Figure 1 The diagram is shown schematically. Furthermore, in this exemplary embodiment, the braking system 110 includes an automatic input unit 114 connected to the central control unit 112 of the braking system 110. This input unit 114 can output external control signals for controlling the braking system 110 to the central control unit 112.

[0043] also, Figure 1 The braking system 110 shown includes a method for... Figure 1The diagram shows a braking device 1 for each of the two wheels 101. Each braking device has a brake caliper 3 attached to and supported on the vehicle body 102. A brake disc 2, in each case, is fixedly attached to the wheel 101 as a reverse braking component for co-rotation. This brake disc is engaged by the brake caliper 3 around it using brake pads (not explicitly shown), and the brake caliper 3 is stationary relative to the brake disc. Furthermore, each braking device 1 has a brake actuator with an electric actuation motor and a wheel brake control unit 120 for controlling the corresponding brake actuator. Each wheel 101 and therefore each braking device 1 is equipped with a wheel speed sensor unit 121 configured to provide the wheel speed of the associated wheel 101 to the associated braking device 1, which the wheel brake control unit 120 uses as the basis for controlling the corresponding brake actuator. Furthermore, the wheel brake control unit 120 is configured to control the corresponding brake actuator based on a provided alternative wheel speed, which is advantageous, particularly when wheel speed cannot be provided to the wheel brake control unit due to an interruption related to the wheel speed sensor unit 121. Different possibilities are provided for providing the alternative wheel speed, which will be discussed in more detail below with reference to the other figures. In this respect, one variation specifies that the wheel speed provided by the wheel speed sensor unit 121 is set to be retrieved via the vehicle's data transmission system 111, particularly via the vehicle's CAN bus. Therefore, the wheel speed assigned to the wheel brake control unit is controlled by the wheel brake actuator based on the alternative wheel speed provided by the wheel brake sensor unit 121. Figure 1 The wheel speed determined by the wheel speed sensor unit 121 of the braking device 1 on the right side of the center is provided as a substitute wheel speed via the data transmission system 111 of the associated wheel brake control unit 120. This data transmission system 111 is, for example, used for... Figure 1 Braking device 1 is shown on the left side of the middle section.

[0044] Figure 2a and Figure 2bSchematic diagrams of chassis 100 are shown, each having an exemplary embodiment of a braking system 110 constructed according to the invention. The motor vehicle has four wheels 101, each wheel 101 being assigned a braking device 1 (BU1, BU2, BU3, BU4) of the braking system 110. Furthermore, in this exemplary embodiment, the braking system 110 includes a first input unit 113 and a second input unit 114, each capable of transmitting braking requirements to the braking system 110 via the braking device 1 (BU1, BU2, BU3, BU4). Specifically, the input unit 114 may be assigned to a driver assistance system and may be signal-connected to the braking system 110 via a data transmission system 111, particularly via the motor vehicle's CAN bus. In contrast, in this exemplary embodiment, the input unit 113 is a brake pedal or brake pedal sensor, which is assigned to the brake pedal and specifically configured to detect the actuation of the brake pedal by the vehicle user and transmit it as a braking demand via communication link 135 to the wheel brake control unit 120 (BC1, BC2, BC3, BC4) of the braking system 110. In this exemplary embodiment, communication link 135 is a sensor line. When the brake pedal is actuated, the brake pedal sensor 113 advantageously detects the brake pedal position, particularly in real time. Therefore, the corresponding wheel brake control unit 120 (BC1, BC2, BC3, BC4) can also preferably derive the brake pedal acceleration under actuation conditions, and the brake pedal acceleration can be considered for use in controlling the corresponding brake actuator 4 of the braking system 110.

[0045] exist Figure 2a and Figure 2b In the exemplary embodiment shown, each of the four braking devices 1 (BU1, BU2, BU3, BU4) has a brake actuator 4 (BM1, BM2, BM3, BM4) and a wheel brake control unit 120 (BC1, BC2, BC3, BC4). Wheel speed sensors 121 (S1, S2, S3, S4) are connected to the wheel brake control unit 120 in their respective cases. Figure 2a During normal operation, the actual values ​​of rotational position and wheel speed P1, P2, P3, and P4 are output in real time to the corresponding wheel brake control units 120 (BC1, BC2, BC3, BC4). The corresponding wheel brake control units 120 (BC1, BC2, BC3, BC4) are preferably integrated with the braking device 1 and electrically connected to the brake actuator 4, which in each case has an electric actuation motor 41, 42, through which brake engagement can be controlled.

[0046] like Figure 2a As shown, each of the four wheel brake control units 120 (BC1, BC2, BC3, BC4) can receive wheel speeds P1, P2, P3, and P4 from the associated wheel speed sensor 121 during uninterrupted normal operation. Therefore, for example, during uninterrupted normal operation, wheel brake control unit BC1 can receive wheel speed P1 from wheel speed sensor 121 (S1); wheel brake control unit BC2 can receive wheel speed P2 from wheel speed sensor 121 (S2), and so on. Then, during normal operation, wheel brake control unit BC1 actuates the associated brake actuator 4 (BM1) considering the wheel speed P1 provided by the associated wheel speed sensor unit 121 (S1) to fulfill the braking demand transmitted by input unit 113 or input unit 114. Similarly, during normal operation, wheel brake control unit BC2 actuates the associated brake actuator 4 (BM2) considering the wheel speed P2 provided by the associated wheel speed sensor unit 121 (S2) to fulfill the transmitted braking demand. In the same manner, wheel brake control units BC3 and BC4 actuate the associated brake actuators 4 (BM3) and 4 (BM4).

[0047] However, in this exemplary embodiment, it is not only specified that the wheel brake control unit 120 (BC1, BC2, BC3, BC4) receives braking requests from the input unit 113 via the corresponding communication link 135, wherein the braking requests are preferably transmitted as a first signal Sg1 by the input unit 113 in a first frequency range on the order of 1 kHz. This is because it is further specified that the wheel brake control unit 120 (BC1, BC2, BC3, BC4) includes a modulation unit, through which the wheel brake control unit 120 (BC1, BC2, BC3, BC4) provides wheel speeds P1, P2, P3, P4 received from the associated wheel speed sensors 121 (S1, S2, S3, S4) as a second signal Sg2, which is provided to at least one of the other wheel brake controller units 120 (BC1, BC2) via the communication link 135, specifically by modulating the second signal Sg2 onto the first signal Sg1, which preferably occurs in a second frequency range on the order of 100 kHz, and... Figure 2bThe diagram is schematically shown. Specifically, it can be specified here that the central control unit 112 designates which of the wheel brake control units 120 (BC1, BC2, BC3, BC4) will provide the received wheel speeds P1, P2, P3, P4 as a second signal Sg2 via communication link 135 to the other wheel brake control units 120 as a substitute for wheel speed EP1. Therefore, in this exemplary embodiment, the wheel brake control unit BC1 will receive the wheel speed P1 from the relevant wheel speed sensor unit S1 as a signal Sg2 via sensor line 135 (in... Figure 2b The wheel speed EP1 is provided to other wheel brake control devices BC2, BC3, and BC4 as an alternative wheel speed. Here, the allocation of transmission and reception for the wheel brake control unit 120 can be changed by the central control unit 112, particularly periodically. Specifically, all detected wheel speeds can also be transmitted via communication link 135, wherein different frequency bands are preferably allocated to the wheel brake control units.

[0048] exist Figure 2a In normal operation, the alternative wheel speed EP1 can then be used specifically for diagnostic purposes, particularly for comparison with further detected wheel speeds P2, P3 and P4, in order to infer a failure of sensor 121, for example, inferring a failure of sensor 121 if the deviation exceeds a tolerance threshold.

[0049] However, in the event of an interruption in either the wheel speed sensor 121 or the signal line—through which the wheel speed sensor 121 transmits wheel speed to the wheel brake control unit 120—the wheel brake control unit 120 uses an alternative wheel speed instead of the wheel speed provided by the wheel speed sensor 121 to actuate the associated brake actuator 4, taking into account the provided alternative wheel speed EP1. Figure 2b This type of interruption situation related to wheel speed sensor 121 (S2) is outlined in the document. Therefore, wheel brake control unit BC2 may no longer receive wheel speed P2 from wheel speed sensor 121 (S2). Instead, wheel brake control unit BC2 demodulates the signal transmitted via communication link 135 and receives wheel speed P1' provided by wheel brake control unit BC1 as a substitute wheel speed EP1. Then, wheel brake control unit BC2 controls the associated brake actuator 4 (BM2) taking into account the received substitute wheel speed EP1. Additionally, as an example, Figure 2b The diagram shows a first signal Sg1, which serves as a PWM signal for braking demand, and a second signal Sg2, modulated onto it, which serves as a substitute for wheel speed EP1.

[0050] Furthermore, in this exemplary embodiment, the wheel brake control units 120 (BC1, BC2, BC3, BC4) are advantageously configured to exchange signals with the central control unit 112, which is configured as an ECU, and to actuate the brake actuator 4 under other specifications of the central control unit 112. However, according to a design variant not shown here, the central control unit 112 may also be omitted.

[0051] See below for reference Figure 3 , Figure 4 and Figure 5 An advantageous embodiment of the brake actuator 4 will be explained in more detail. Here, the corresponding brake actuator 4 advantageously has a housing 45, and the wheel brake control unit 120 is as follows: Figure 5 The wheel brake control unit is arranged in the housing 45 as shown. It has circuitry connected to the actuation motors 41 and 42 and the central control unit 112. Therefore, the wheel brake control unit 120 is integrated with the braking device 1.

[0052] In order to Figure 2a and Figure 2b as well as Figure 4 and Figure 5 The wheel speed sensor 121, which is schematically indicated in the diagram, is connected, and the brake actuator 4 has a connector device 46, in particular an electrically inserted connector arranged on the housing 45.

[0053] Figure 3 An exemplary embodiment of a braking device 1 of a braking system 110 according to the present invention is shown, wherein the braking device 1 is configured as a disc brake. The braking device 1 includes a brake disc 2 that forms a reverse braking component and is connected to a vehicle wheel 101 (not shown here), which is rotatable about a wheel axis R. Brake calipers 3 engage with the two axial end surfaces of the brake disc 2. The brake disc 2 is configured here as a non-ventilated brake disc made of a solid material. Alternatively, the brake disc 2 may also be configured as an internally ventilated brake disc.

[0054] Brake actuator 4 is attached to brake caliper 3. Brake actuator 4 includes actuation device 5, which extends axially in the direction of axis A, which is parallel to wheel axis R and specifies the adjustment direction V of actuation device 5. Brake actuator 4 includes electric actuation motor 41 to which wheel brake control unit 120 is distributed. Here, wheel brake control unit 120 is configured to determine alternative wheel speed based on vibration of brake disc 2, which is used for wheel speed measured by means of wheel sensor unit 121. The fact utilized here is that during the intended operation of braking device 1 in a moving motor vehicle, vibration of brake disc occurs in the range between ±0.01 mm and ±1 mm. Due to the mechanical connection via a very small air gap between brake disc 2 and brake pads, which can be within a tenth of a millimeter, these vibrations induce ripple current in actuation motor 41 of braking device 1. The mechanical connection can be seen here, especially Figure 5 The mechanical connections can be seen. The wheel brake control unit 120 measures the current of the actuation motor 41 and / or the second actuation motor 42, as will be explained below, and in this respect, it can also detect the resulting ripple current and evaluate the ripple current based on the wheel speed. It can be specified here that the wheel brake control unit 120 transmits the frequency of the detected ripple current and the wheel speed determined by means of the wheel speed sensor unit 121 assigned to the braking device 1 to the central control unit 112, for example, as... Figure 1 As shown, the artificial intelligence system of the central control unit 112 is trained to allocate the ripple current frequency to the corresponding wheel speed based on the transmitted values. Then, in the event of a failure of the wheel speed sensor unit 121, an alternative wheel speed can be advantageously provided via the detection frequency of the ripple current of the wheel brake control unit 120. This alternative wheel speed can replace the wheel speed from the wheel speed sensor unit 121 for actuating the motor to achieve the received braking demand.

[0055] Figure 4 A view of the brake caliper 3 as seen from the brake disc 2 is shown.

[0056] As in Figure 5 As can be seen in the cross-sectional view along axis A, the brake disc 2 is axially arranged between two brake pads 31 and 32. One brake pad 31 is fixedly supported on the brake caliper 3 on the side opposite to the brake actuator 4. The other brake pad 32, forming the brake component of the braking device 1, is attached to the actuator 5 and can be adjusted by the actuator 5 in the axial adjustment direction V (indicated by axis A) toward the brake disc 2 to produce brake engagement, such as... Figure 5 As indicated by the arrow in the image.

[0057] In the non-actuated state of braking device 1, the problem has been solved and Figure 5 The axial air gap L, schematically shown with an exaggerated width, is located between the brake disc 2 and the adjustable brake pad 32.

[0058] The structure of the actuation device 5 is as follows Figure 5 As shown, and in Figure 7 The details are shown in magnified view. The actuation device 5 includes a first actuation driver 6 with a ramp bearing, and a second actuation driver 7 that is axially (with respect to axis A) connected in series to the first actuation driver 6 and has a spindle driver.

[0059] In the example shown, the first actuation driver 6, constructed as a ramp bearing, includes a drive-side cam disk 61 fixedly supported on the brake actuator 4 and rotating together with it, and an output-side cam disk 62. Ball bearings 63 are arranged between the cam disks 61 and 62. Figure 6 As can be seen in the schematic exposed view, cam disks 61 and 62 have ramped raceways 64, which are arranged axially opposite each other and inclined relative to axis A, and balls 63 can roll between the raceways 64. Output-side cam disk 62 ( Figure 6 The rotation of the top of the drive-side cam disk 61 relative to the stationary drive-side cam disk 61 (as indicated schematically by the curved arrow) causes the output-side cam disk 62 to adjust linearly in the adjustment direction V parallel to axis A. Therefore, as... Figure 5 As shown, the brake pad 32 can be braked by actuation of the first actuation driver 6.

[0060] A cam disk 62 is connected to a coaxial gear 65, which is configured as a spur gear and forms a drive wheel within the context of this invention. Gear 65 engages with a first electric actuation motor 41. This enables the rotational drive of the cam disk 62 and thus the actuation of the first actuation driver 6. In the illustrated example, the second actuation driver 7, configured as a spindle driver, has a threaded spindle 71 on the output side, which engages in the internal thread of the drive-side spindle nut 72. This internal thread is constructed in the output-side cam disk 62 of the first actuation driver 6, resulting in the functions of the output-side cam disk 62 and the drive-side spindle nut 72 being combined into a single structural unit.

[0061] A threaded spindle 71 is connected via a hub portion 74 to a coaxial gear 75, which is rotatably mounted in the brake actuator 4 in an axially fixed manner. The threaded spindle is coupled to the gear 75 via a driver 73 in a torque-transmitting but axially movable manner. The driver 73 may have, for example, radially projecting protrusions or teeth that engage in an axially displaceable manner in an axial groove in the hub portion 74.

[0062] Like gear 65, gear 75 can be constructed as a spur gear and arranged coaxially adjacent to gear 65. Gear 75 engages with the second electric actuation motor 42. This enables the rotational drive of the threaded spindle 71 and thus the actuation of the second actuation driver 7. The threaded spindle 71 is axially connected to the pressure member 44 via a thrust bearing 43, such as an axial friction-reducing bearing as shown, to which a movable brake pad 32 is attached, as follows: Figure 5 What you see. Pressure component 44 can also be called a piston.

[0063] The clutch device according to the invention has a friction element 8, which is guided from the cam disc 62 as a coaxial tapered attachment to the second actuation drive 7. The tapered attachment has a tapered friction surface 81 arranged on the outer side of the outer cone. The friction element 81 can preferably be constructed as a single piece with the cam disc 62 / spindle nut 72.

[0064] Friction element 8 is frictionally locked to reverse friction element 9 during clutch engagement. Here, a tapered attachment is axially immersed in a corresponding tapered opening of reverse friction element 9, the tapered opening having a tapered friction surface 91 arranged within an inner cone. During clutch engagement, friction surface 81 and reverse friction surface 91 abut against each other in a frictionally locked manner, as can be achieved by... Figure 7 As can be clearly seen, the reverse friction element 9 is connected to the gear 75 via a drive 92 in a torque-transmitting but axially movable manner, the drive 92 engaging in a corresponding groove 76 in the hub portion 74 or the gear 75 in an axially displaceable manner.

[0065] A spring element 93 is arranged between the gear 75 or the hub portion 74 connected to the gear 75 and the reverse friction element 9. The reverse friction element 9 is elastically supported against the friction element 8 by its axially acting spring force. Therefore, a limiting clutch torque is generated for the friction clutch formed by the friction element 8 and the reverse friction element 9.

[0066] To actuate the braking device 1, gears 65 and 75 rotate synchronously, resulting in the first actuation drive 6 performing a working stroke in the adjustment direction V, thus causing the brake pad 32 to pass through the air gap L and engage with the brake disc 2. Synchronous drive of gears 65 and 75 can be achieved by synchronizing the drive speeds of actuation motors 41 and 42, or by driving only one of actuation motors 41 or 42 while the corresponding other actuation motor 42 or 41 idles. A friction-locking clutch engages between friction element 8 and reverse friction element 9, thus ensuring the synchronous rotation of gears 65 and 75. Because friction element 8 and reverse friction element 9 are arranged wholly or at least partially within gears 65 and 75, a particularly compact overall design can be achieved.

[0067] To adjust the width of the air gap L, gear 65 is locked or blocked, specifically by the corresponding actuation of the first actuating motor 41. Gear 75 rotates relative to gear 65 via the second actuating motor 42, wherein the friction clutch slides continuously in a slippery manner. Therefore, the second actuating drive 7 is uniformly adjusted, resulting in the air gap L width also being continuously set and adjusted to compensate for, for example, wear of the brake pads 32.

[0068] Figures 3 to 7 The braking device shown is a floating caliper brake (also known as a sliding caliper brake). Here, brake pads 32 are pressed against the brake disc 2 by pressure member 44, and brake pads 31 are pressed by brake calipers 3, which are capable of displacement relative to the brake disc 2 in the direction of axis A. Alternatively, the proposed solution can also be used in the case of a fixed caliper brake.

[0069] The exemplary embodiments shown in and explained in conjunction with the accompanying drawings are used to explain the present invention and are not intended to limit the invention.

[0070] Attached text

[0071] 1. Braking system (BU1, BU2, BU3, BU4)

[0072] 100 chassis

[0073] 101. Wheel (vehicle wheel)

[0074] 102 Vehicle body

[0075] 103 Steering Knuckle

[0076] 104 Steering Axle

[0077] 105 Steering Wheel

[0078] 106 Steering Gear

[0079] 107 tie rod

[0080] 110 Braking System

[0081] 111 Data Transmission System

[0082] 112 Central Control Unit

[0083] 113 Brake Pedal (Input Unit)

[0084] 114 Input Units

[0085] 120 Wheel Brake Control Units (BC1, BC2, BC3, BC4)

[0086] 121 Wheel speed sensor units (S1, S2, S3, S4)

[0087] 135 communication link

[0088] 2. Brake disc (reverse braking component)

[0089] 3 Brake calipers

[0090] 31, 32 Brake pads (brake components)

[0091] 4 Brake actuators (BM1, BM2, BM3, BM4)

[0092] 41, 42 Actuation Motors

[0093] 43 Thrust bearing

[0094] 44 Pressure components

[0095] 45. Housing

[0096] 46 Connector Equipment

[0097] 5. Actuation equipment

[0098] 6 First-hand drive

[0099] 61 Cam plate

[0100] 62 Cam plate (connected to spindle nut 72)

[0101] 63 Spherical components

[0102] 64 Rolling Track

[0103] 65 Gears (First Drive Wheel)

[0104] 7 Second Actuation Driver

[0105] 71 Threaded spindle

[0106] 72 Spindle nut (connected to cam disc 62)

[0107] 73 drives

[0108] 74 Wheel hub section

[0109] 75 Gear (Second Drive Wheel)

[0110] 76 slots

[0111] 8 Friction Elements

[0112] 81 Friction Surface

[0113] 9. Reverse friction element

[0114] 91 Reverse friction surface

[0115] 92 drives

[0116] 93 Spring Components

[0117] Wheel speeds P1, P2, P3, P4

[0118] P1' is the wheel speed relayed by the wheel brake control unit (BC1).

[0119] EP1 Replaces wheel speed

[0120] Axis A

[0121] R wheel axle

[0122] V Adjust direction

[0123] L air gap

[0124] Sg1 First Signal

[0125] Sg2 Second Signal

Claims

1. A method for operating an electromechanical braking system (110) in a motor vehicle, wherein, The braking system (110) has at least one input unit (113, 114) and at least two braking devices (1, BU), through which braking requirements are transmitted, and each of the braking devices (1, BU) includes a brake actuator (4, BM) having at least one electric actuation motor (41, 42), wherein each of the braking devices (1, BU) is equipped with a wheel brake control unit (120, BC) and a wheel speed sensor unit (121). The wheel speed sensor unit (121) of the relevant wheel brake control unit (120, BC) provides wheel speed (P) to the corresponding braking device (1, BU). The alternative wheel speed (EP) provided by the associated wheel speed sensor unit (121) for the wheel speed (P) is provided to the wheel brake control unit (120, BC). The wheel brake control unit (120, BC) actuates the brake actuator (4, BM) in normal operation, taking into account the wheel speed (P) provided by the associated wheel speed sensor unit (121), in order to fulfill the transmitted braking demand. The wheel brake control unit (120, BC) actuates the brake actuator (4, BM) in consideration of the provided alternative wheel speed (EP) in order to realize the transmitted braking demand in the event that the wheel speed (P) provided by the associated wheel speed sensor unit (121) is interrupted.

2. The method according to claim 1, characterized in that, The wheel brake control units (120, BC) are connected to each other via a data transmission system (111) for exchanging data, wherein wheel speed (P) is provided via the data transmission system (111) to the wheel brake control units (120, BC) that are assigned to the braking devices (120, BU) by at least one wheel speed sensor unit (121) that is not directly assigned to the braking devices (120, BU).

3. The method according to any one of the preceding claims, characterized in that, The input units (113, 114) of the braking system (110) are connected via a communication link (135) to the corresponding wheel brake control units (120, BC) to transmit the braking demand, wherein the wheel speed (P) provided by one of the other wheel brake control units (120, BC) as an alternative wheel speed (EP) is provided by the wheel brake control unit (120, BC) via the communication link (135) to the wheel brake control unit (120, BC) assigned to the braking device (1, BU).

4. The method according to claim 3, characterized in that, The braking demand is transmitted via the communication link (135) in a first frequency range, and the alternative wheel speed (EP) is transmitted via the communication link (135) in a second frequency range, wherein the second frequency range is a frequency range different from the first frequency range.

5. The method according to claim 3 or 4, characterized in that, The braking demand is transmitted as a first signal (Sg1) to the wheel braking control unit (120, BC) via the communication link (135), and the alternative wheel speed (EP) is transmitted as a second signal (Sg2) modulated onto the first signal (Sg1) via the communication link (135).

6. The method according to claim 5, characterized in that, The corresponding wheel brake control unit (120, BC) that provides the alternative wheel speed (EP) modulates the alternative wheel speed (EP) into the second signal (SG2), and the corresponding wheel brake control unit (120, BC) demodulates the second signal (SG2).

7. The method according to any one of the preceding claims, characterized in that, The input unit (113) is a brake pedal sensor, which transmits the brake pedal position as a braking demand in an analog or digital manner.

8. The method according to any one of the preceding claims, characterized in that, At least one of the braking devices (1, BU) includes a brake disc (2), wherein the wheel brake control unit (120, BC) assigned to this type of braking device (1, BU) having a brake disc (2) determines the alternative wheel speed (EP) or another alternative wheel speed (EP') based on the vibration of the brake disc (2).

9. The method according to claim 8, characterized in that, The wheel brake control unit (120, BC) assigned to the brake device (1, BU) having a brake disc (2) detects the ripple current caused by the vibration of the brake disc (2) and due to the mechanical connection in at least one actuating motor (41, 42) of the brake device (1, BU), and limits the alternative wheel speed (EP) or the other alternative wheel speed (EP') based on the detected ripple current.

10. The method according to claim 9, characterized in that, During normal operation, the artificial intelligence system, taking into account the wheel speed (P) provided by the wheel speed sensor unit (121) assigned to the braking device (1, BU), trains the determination of the alternative wheel speed (EP) or the other alternative wheel speed (EP') based on the ripple current detected for the braking device (1, BU).

11. The method according to any one of the preceding claims, characterized in that, The braking device (1, BU) is connected to a central control unit (112), which is configured to be connected to at least one input unit (113, 114). Braking demand is input to the central control unit (112) from at least one of the input units (113, 114). The central control unit (112) actuates the brake actuator (4) via a control signal. The central control unit (112) outputs control signals to at least two wheel brake control units (120, BC), each of which is assigned to the braking device (1, BU) and actuates the brake actuator (4) of the corresponding braking device (1, BU).

12. The method according to any one of the preceding claims, characterized in that, The braking device (1) has an actuation device (5) that can be connected to the at least one actuation motor (41, 42, BM), and includes a first actuation driver (6) and a second actuation driver (7). The second actuation driver (7) is connected in series with the first actuation driver (6) and acts on a braking member (32) that can engage with the reverse braking member (2) in the direction of axis (A). The first actuation driver (5) has a rotatably driven first drive wheel (65) that can apply a first driving torque to the first drive wheel (65) for actuation purposes. The second actuation driver (7) has a rotatably driven second drive wheel (75) that is coaxial with the first drive wheel (65) and can apply a second driving torque to the second drive wheel (75) for actuation purposes. A clutch device is arranged between the first drive wheel (65) and the second drive wheel (75).

13. The method according to claim 12, characterized in that, The clutch device is configured as a friction clutch (8, 9) and has a predetermined clutch torque. When the clutch torque is exceeded, the first drive wheel (65) slides relative to the second drive wheel (75) in a sliding manner. The first drive wheel (65) and the second drive wheel (75) are driven synchronously to actuate the first actuation actuator (6). As a result, the second actuation actuator (7) remains unacted. In order to actuate the second actuation actuator (7), the second drive wheel (75) is driven while the first drive wheel (65) is stationary relative to the second drive wheel (75). As a result, the friction clutch slides and the first actuation actuator (6) remains unacted.

14. A braking system (110) for a motor vehicle, comprising: At least one input unit (113, 114) is used to transmit braking requirements; At least two braking devices (1, BU), each of which is provided with a wheel speed sensor unit (121) configured to provide a wheel speed (P) to the associated braking device (1, BU); wherein each of the braking devices (1, BU) includes a brake actuator (4) having at least one electric actuation motor (41, 42), characterized in that each of the braking devices (1, BU) is provided with a wheel brake control unit (120, BC) for controlling the corresponding brake actuator (4), wherein the wheel brake control unit (120, BC) is configured to control the brake actuator (4) in consideration of the wheel speed (P) provided by the associated wheel speed sensor unit (121), and is also configured to control the brake actuator (4) in consideration of an alternative wheel speed (EP) for the wheel speed (P) provided by the associated wheel speed sensor unit (121).

15. The braking system (110) according to claim 14, characterized in that, The braking system (110) is configured to operate in accordance with the method according to any one of claims 1 to 13.

16. The braking system (110) according to claim 14 or 15, characterized in that, The braking device (1, BU) is connected to the central control unit (112), which is configured to be connected to the at least one input unit (113, 114), and the wheel braking control unit (120, BC) is connected to the central control unit (112).

17. The braking system (110) according to any one of claims 14 to 16, characterized in that, The braking device (1, BU) includes an actuating device (5) and a braking component (32) connected to the actuating device (5). The braking component (32) can be adjusted by the actuating device (5) along an axis (A) and can engage with a reverse braking component (2). The actuating device (5) has a first actuating driver (6) and a second actuating driver (7), the second actuating driver (7) being connected in series to the first actuating driver (6). The first actuating driver (6) has a rotatably driven first drive wheel (65), and the second actuating driver (7) has a rotatably driven second drive wheel (75), the second drive wheel being coaxial with the first drive wheel (65). A clutch device (8, 9) is arranged between the first drive wheel (65) and the second drive wheel (75). The clutch device (8, 9) is preferably configured as a friction clutch (8, 9) having a friction element (8), which can be connected to a reverse friction element (9) in a frictionally locked manner during clutch engagement.

Images