Brake booster control device for an electrically controllable brake booster and modulation device for at least one hydraulic brake system component

Abstract

Brake booster control device (10) for an electrically controllable brake booster, with a first connection device (10a, 10b) by means of which the brake booster control device (10) can be connected to a vehicle bus system (12) such that at least one first signal (b1 to b9) transmitted via the vehicle bus system (12) can be received; and a brake booster control device (10c), by means of which a desired brake booster mode of the brake booster can be determined taking into account at least the at least one received first signal (b1 to b9) and a brake booster control signal corresponding to the determined desired brake booster mode can be output to the brake booster, so that the brake booster can be controlled by means of the brake booster control signal into an actual brake booster mode corresponding to the desired brake booster mode; characterized in that by means of the first connection device (10a, 10b) at least one first information and / or control signal (b1 to b9) output by a modulation device (14) for at least one hydraulic brake system component to the vehicle bus system (12) can be received as the at least one first signal (b1 to b9), wherein the brake booster control device (10c) is designed, after receiving the at least one first information and / or control signal (b1 to b9), to define the target brake booster mode as the at least one first signal (b1 to b9), at least taking into account the at least one first information and / or control signal (b1 to b9).

Description

[0001] The invention relates to a brake booster control device for an electrically controllable brake booster and an electrically controllable brake booster. The invention also relates to a modulation device for at least one hydraulic brake system component and a hydraulic unit. Furthermore, the invention relates to a braking system for a vehicle. State of the art

[0002] DE 103 27 553 A1 describes an electromechanical brake booster. The brake booster is connected, for example, via a vehicle bus, to a sensor for detecting the pedal force acting on a piston rod. Furthermore, the braking system equipped with the electromechanical brake booster also includes several hydraulic braking system components, such as pumps, switching valves, high-pressure switching valves, wheel inlet valves, and wheel outlet valves. Disclosure of the invention

[0003] The invention provides a brake booster control device for an electrically controllable brake booster having the features of claim 1, an electrically controllable brake booster having the features of claim 7, a modulation device for at least one hydraulic brake system component having the features of claim 8, a hydraulic unit having the features of claim 15 and a brake system having the features of claim 16. Advantages of the invention

[0004] The present invention enables communication between the brake booster control device and the modulation device, by means of which the functionality of at least one of the two devices can be optimized with respect to the other of the two devices. The present invention thus provides communication modules that, together with the software and hardware of the brake booster control device and / or the modulation device, open up expanded application potential.

[0005] For example, by means of the communication between the brake booster control device and the modulation device, which can be implemented based on the present invention, the energy consumption / energy requirement of at least one of the two devices can be reduced. Likewise, by means of the communication between the brake booster control device and the modulation device, the haptics of a brake actuating element, such as pedal haptics, can be improved. The haptics of the brake actuating element conventionally result from the properties of the hydraulic brake system and the brake booster. By means of the targeted interaction of the brake booster and the hydraulic brake system, in particular the brake booster and a hydraulic brake system with ESP function, which can be implemented by means of the present invention, the haptics of the brake actuating element can be further improved.

[0006] As explained in more detail below, driving comfort can also be increased by means of the present invention.

[0007] The present invention can be easily implemented by implementing a data protocol in the modulation device and / or the brake booster control device for the interaction of the devices and / or for optimizing their overall functions with associated algorithms. Thus, the use of the present invention is not associated with significant costs.

[0008] In an advantageous embodiment, at least one second information and / or control signal can additionally be defined for the modulation device by means of the brake booster control device, which can be specifically output to the modulation device via the vehicle bus system by means of the first connection device. Thus, the advantageous brake booster control device can not only optimize its own functionality with respect to the at least one first information and / or control signal from the modulation device, but can also additionally output information to the modulation device and / or advantageously affect the functionality of the modulation device.

[0009] For example, the at least one second information and / or control signal that can be determined by the brake booster control device is at least one status bit and / or a handshaking signal. Using the status bit, the brake booster control device can inform the modulation device that a standard / advantageous mode of operation of the brake booster control device can be assumed. The handshaking signal can be used to excite the modulation device to output a response signal within a specific time interval. The brake booster control device can thus check itself whether the modulation device is in a state suitable for communication.

[0010] Furthermore, the at least one second information and / or control signal that can be determined by the brake booster control device can include a brake actuation state, a brake pressure variable, a braking distance variable, a desired vehicle deceleration, and / or a desired braking torque. The variables listed here are conventionally provided to the brake booster control device by means of at least one sensor. By transmitting at least one of the provided variables to the modulation device, the receiving modulation device can additionally optimize the functioning of the at least one hydraulic brake system component controlled by it.

[0011] Alternatively or in addition, the at least one second information and / or control signal that can be determined by the brake booster control device can include information regarding an active pressure buildup carried out by the brake booster without a driver braking request. This easily ensures that the modulation device can optimize its own functionality with regard to the active pressure buildup carried out by the brake booster, even though the driver does not request deceleration of the vehicle.

[0012] Furthermore, the at least one second information and / or control signal that can be determined by means of the brake booster control device can include information regarding a driver braking request exceeding the maximum achievable gain of the brake booster and / or a request for hydraulic brake boosting by means of the at least one hydraulic brake system component. In this case, the at least one hydraulic brake system component can preferably be excited to hydraulic brake boosting by means of the modulation device receiving the information regarding the driver braking request exceeding the maximum achievable gain of the brake booster and / or the request for hydraulic brake boosting.Thus, even in a situation where the brake booster cannot independently perform the brake boost, for example, as specified by the driver, hydraulic brake pressure boosting can still be achieved using at least one hydraulic brake system component. This ensures improved braking comfort for the driver.

[0013] The advantages described in the preceding paragraphs are also guaranteed in an electrically controllable brake booster with such a brake booster control device.

[0014] In an advantageous embodiment of the modulation device, the second information and / or control signal output by the brake booster control device to the vehicle bus system can be received as the at least one signal by means of the second connection device. After receiving the second information and / or control signal, the hydraulic control device is configured to define the at least one desired operating mode as the at least one second signal, at least taking the second information and / or control signal into account. Thus, the functioning of the modulation device in interaction with the brake booster control device can also be optimized.

[0015] The at least one first information and / or control signal that can be determined by the hydraulic control device can also be at least one status bit and / or a handshaking signal. Thus, the modulation device can not only inform the brake booster control device of its own standard functionality using the status bit, but can also check the brake booster control device's communication capability using the handshaking signal.

[0016] Furthermore, the at least one first information and / or control signal that can be determined by means of the hydraulic control device can include wheel brake cylinder operating point information, wheel pressure estimation information, wheel pressure measurement information, brake pressure estimation information, brake pressure measurement information, maximum deceleration estimation information, friction coefficient information, and / or road gradient information. In particular, when the modulation device is designed to execute an ESP function, the information listed here is conventionally output to the modulation device.By means of the advantageous embodiment of the present invention described here, the information provided to the modulation device can also be passed on to the brake booster control device, whereby the brake booster control device can optimize the control of the brake booster taking into account the forwarded information.

[0017] As an alternative or in addition, the at least one first information and / or control signal that can be determined by means of the hydraulic control device can comprise vehicle standstill information and / or a request to reduce brake booster. In this case, the brake booster control device is preferably designed, after receiving the vehicle standstill information and / or the request to reduce brake booster, to set the target brake booster mode such that the brake booster can be excited to reduce brake booster. In this way, the energy consumption of the brake booster can be reduced.

[0018] Likewise, the at least one first information and / or control signal that can be set by the hydraulic control device can include a permission and / or a request to increase the brake booster. Advantageously, after receiving the permission and / or the request to increase the brake booster, the brake booster control device is configured to set the target brake booster mode such that the brake booster can be excited to increase the brake booster.

[0019] Furthermore, the at least one first information and / or control signal that can be determined by the hydraulic control device can comprise volume shift information regarding a brake fluid volume to be shifted from a master brake cylinder and / or regarding a brake fluid volume returned to the master brake cylinder. Furthermore, after receiving the volume shift information, the brake booster control device can be configured to set the target brake booster mode such that the brake booster can be excited to a corresponding increase in brake force amplification. As explained in more detail below, the haptics of a brake actuating element, such as a pedal haptics, can also be improved in this case.

[0020] The advantages described here are also guaranteed with a hydraulic unit which comprises at least one hydraulic brake system component and a corresponding modulation device.

[0021] Furthermore, the described advantages can also be realized by means of a braking system with such a brake booster control device / a brake booster equipped therewith and a correlating modulation device / a hydraulic unit designed therewith. Short description of the drawings Further features and advantages of the present invention will be explained below with reference to Fig. 1, which shows a schematic representation of embodiments of the brake booster control device and the modulation device. Embodiments of the invention

[0022] Fig. 1 shows a schematic representation of embodiments of the brake booster control device and the modulation device.

[0023] The Fig.The brake booster control device 10 schematically illustrated in Figure 1 is designed to control an electrically controllable brake booster (not shown). The brake booster control device that can be controlled / operated by the brake booster control device can, for example, be an electromotive / electromechanical brake booster. An electromotive brake booster has the advantages that it does not require hydraulics near a driver's foot, functions without a pneumatic vacuum supply, and also functions when the vehicle engine is switched off. However, the brake booster control device 10 described below is not limited to interaction with an electromotive brake booster. Instead, the brake booster control device 10 can interact with any brake booster that is (largely) electronically tunable / controllable and / or electrically operable.

[0024] The brake booster control device 10 can, in particular, be designed as a subunit of the electrically controllable brake booster. However, the brake booster control device 10 can also be designed as a compact unit that can be arranged separately from the electrically controllable brake booster. The brake booster control device 10 can thus be designed with a great deal of design freedom.

[0025] The brake booster control device 10 comprises a first connection device 10a and 10b, by means of which the brake booster control device 10 can be connected to a vehicle bus system 12 such that at least one first signal b1 to b9 transmitted via the vehicle bus system can be received. The first connection device 10a and 10b can, for example, have a data output 10a and a data input 10b. However, the first connection device 10a and 10b can also be designed as a single, compact unit.

[0026] The brake booster control device 10 also has a brake booster control device 10c, by means of which a target brake booster mode of the brake booster can be defined taking into account the at least one received signal b1 to b9, and a brake booster control signal (not shown) corresponding to the defined target brake booster mode can be output to the brake booster. Preferably, the brake booster can be controlled by means of the brake booster control signal into an actual brake booster mode corresponding to the target brake booster mode. In particular, a target rotation angle and / or a target rotational speed of a motor of the brake booster can be defined as the target brake booster mode and controlled by means of a supply current as a brake booster control signal.

[0027] Advantageously, at least one first information and / or control signal b1 to b9 output by a modulation device 14 for at least one hydraulic brake system component to the vehicle bus system 12 can be received as the at least one signal b1 to b9 by means of the first connection device 10a and 10b. After receiving the at least one first information and / or control signal b1 to b9, the brake booster control device 10c is designed to define the target brake booster mode as the at least one signal b1 to b9, at least taking into account the at least one first information and / or control signal b1 to b9. The brake booster device 10 can thus be optimized in its functionality with regard to an operating mode and / or information provided by the modulation device 14.

[0028] The brake booster control device 10 and the modulation device 14 can thus communicate with each other in such a way that the functioning of at least the brake booster control device 10 / the brake booster can be optimized. By means of a further development described in more detail below, the functioning of the modulation device 14 / of the at least one hydraulic brake system component controlled thereby can also be improved by means of the communication between the devices 10 and 14. As explained in more detail below, for example, the energy consumption of at least one of the devices 10 and 14 can be reduced by means of the communication that can be implemented between the devices 10 and 14. Furthermore, the communication that can be implemented between the brake booster control device 10 and the modulation device 14 makes it easier for the driver to operate a brake actuating element, such as a brake pedal.Furthermore, the communication between the devices 10 and 14 can be used for a rapid and convenient brake pressure build-up in at least one brake circuit of a brake system equipped with the devices 10 and 14, as will be described in more detail below.

[0029] The vehicle bus system 12, via which the devices 10 and 14 are connected to each other, can be, for example, a CAN bus. However, it should be noted that the vehicle bus system 12 can be configured in a way that is not limited to a CAN bus.

[0030] The modulation device 14 can, in particular, be an ESP device. However, the designability of the modulation device 14 is not limited to this embodiment. Instead of or as a supplement to an ESP function, the modulation device 14 can also be designed to perform an ABS function and / or a tracking controller function. The modulation device 14 can be designed both as a (structural) subunit of a hydraulic unit and as a compact unit that can be arranged separately from the hydraulic unit. The modulation device 14 can be connected / is connected to the vehicle bus system 12 by means of a second connection device 14a and 14b, which is also designed, for example, as a data output 14a and a data input 14b. Thus, at least one second signal a1 to a7 transmitted via the vehicle bus system 12 (to the modulation device 14) can be received.

[0031] The modulation device 14 also has a hydraulic control device 14c, by means of which at least one desired operating mode of the at least one (not shown) hydraulic brake system component (of the brake system equipped with devices 10 and 14) can be determined taking into account the at least one received second signal a1 to a7. The at least one hydraulic brake system component can be, for example, a changeover valve, a high-pressure switching valve, a wheel outlet valve, a wheel inlet valve, and / or a pump. By means of the hydraulic control device, at least one hydraulic control signal (not shown) corresponding to the at least one determined desired operating mode of the at least one hydraulic brake system component can be output to the at least one hydraulic brake system component.The at least one output hydraulic control signal can, for example, be an operating current / supply current of the at least one hydraulic vehicle brake system component. For example, the at least one hydraulic control signal can be used to control / determine the opening state of at least one valve and / or the pumping power of at least one pump. However, the design of the at least one hydraulic brake system component interacting with the modulation device 14 is not limited to the exemplary embodiments listed here and the hydraulic control signals mentioned.

[0032] The at least one hydraulic brake system component can be controlled by means of the hydraulic control signal into at least one actual operating mode corresponding to the at least one desired operating mode. Thus, the modulation device 14 can advantageously be used to selectively reduce or increase a brake pressure in at least one wheel brake cylinder of the brake system equipped with the devices 10 and 14 by means of the at least one hydraulic brake system component.

[0033] The hydraulic control device 14c is additionally designed to determine the at least one first information and / or control signal b1 to b9 for the brake booster control device 10. Using the second connection device 14a and 14b, the at least one first information and / or control signal b1 to b9 can then be output specifically to the brake booster control device 10 via the vehicle bus system 12. Thus, the modulation device 14 can forward information to the brake booster control device 10 and / or adapt the functionality of the brake booster control device 10 to its own requirements.

[0034] In an advantageous development, at least one second information and / or control signal a1 to a7 can additionally be defined for the modulation device 14 by means of the brake booster control device 10c, which can be output to the modulation device 14 in a targeted manner via the vehicle bus system 12 by means of the data output 10a of the first connection device 10a and 10b. Thus, the brake booster control device 10 can additionally be designed to output / forward information to the modulation device 14 and / or to further optimize the functioning of the modulation device 14.

[0035] In this case, at least the second information and / or control signal a1 to a7 output by the brake booster control device 10 to the vehicle bus system 12 can preferably also be received as the at least one second signal a1 to a7 by means of the second connection device 14a and 14b. In this case, the hydraulic control device 14c, after receiving the second information and / or control signal a1 to a7, is designed to define the at least one desired operating mode as the at least one second signal a1 to a7, at least taking into account the second information and / or control signal a1 to a7. The modulation device 14 can thus also optimize its own mode of operation with respect to information transmitted by the brake booster control device 10 and / or a current operation of the brake booster control device 10.

[0036] The advantageous interaction of devices 10 and 14 can be easily realized by implementing a data protocol for coordinating the functions of devices 10 and 14 with associated algorithms. Thus, no (significant) costs are required to implement the advantageous interaction of devices 10 and 14. Instead, the advantageous communication between devices 10 and 14 can be achieved, for example, by means of simple programming of the devices.

[0037] While conventional brake booster controls and hydraulic unit controls operate independently, i.e., are only implemented in stand-alone mode, additional functional potential can be exploited through the electronic cooperation realized by devices 10 and 14. In particular, the brake booster, at least one pump, and / or at least one valve can be used (cooperating / coordinated with one another) to achieve improved braking comfort, reduced energy consumption, and / or an improved brake actuation feel (pedal feel).

[0038] The devices 10 and 14 can, for example, exchange safety signals a1, a2, b1, and b2 with each other. For example, the at least one second information and / or control signal a1 to a7 that can be defined by the brake booster control device 10c can be at least one status bit a1 and / or one handshaking signal a2. Accordingly, at least one status bit b1 and / or one handshaking signal b2, which can be defined by the hydraulic control device 14c as the at least one first information and / or control signal b1 to b9, can also be forwarded to the brake booster control device 10 via the vehicle bus system 12.

[0039] The status bit a1 of the brake booster control device 10, which can be forwarded to the modulation device 14, can, for example, indicate that the brake booster control device 10 is in a functional state (iBooster_OK). Accordingly, the status bit b1, which can be output by the modulation device 14 and forwarded to the brake booster control device 10 via the vehicle bus system 12, can also indicate that the modulation device 14 is reliably in a functional state (ESP_OK). Each of the status bit signals a1 and b1 can each have a data volume of 1 bit. Thus, information advantageous for the interaction of the two devices 10 and 14 can be reliably transmitted using a comparatively low amount of forwarded data.In a further development, the at least one status bit signal a1 and b2 can also describe a function executed by the output device 10 or 14. This can be achieved by extending the status bit signal a1 or b2 to a data volume of up to 65 bits.

[0040] By means of the handshaking signal a2 / handshake signal / monitoring signal output by the brake booster control device 10, the modulation device 14 can be excited to output a response signal within a specific time interval. The brake booster control device 10 thus has the option of actively checking the communication capability and / or response time of the modulation device 14 by determining the time elapsed until the response signal from the modulation device 14 was received. Accordingly, the modulation device 14 can also determine, by means of the handshaking signal b2 / handshake signal / monitoring signal output to the brake booster control device 10, whether a response signal from the brake booster control device 10 can be received within a specific time interval and, therefore, whether sufficient communication and response capability of the brake booster control device 10 can be expected.The modulation device 14 can thus also actively determine whether the brake booster control device 10 responds to the handshaking signal b2 in such a way that it makes sense to coordinate the functioning of the modulation device 14 with the information and / or control commands of the brake booster control device 10. Each of the signals a2 and b2 (ESP_Counter, iBooster_Counter) can have a data volume between 1 ub and 7 ub. The devices 10 and 14 can thus ensure that they only adapt their functioning to one another when this is advantageous.

[0041] The devices 10 and 14 can also be configured for an exchange of data, measured variables, estimated variables, and / or information. For example, the at least one second information and / or control signal a1 to a7 that can be determined by means of the brake booster control device 10c comprises a brake actuation state a3 (brake actuation or non-actuation of the brake actuation element), a brake pressure variable a4, a braking distance variable (adjustment distance of a brake actuation element and / or an input rod), a desired vehicle deceleration (specified by a driver and / or an automatic speed control device), and / or a desired braking torque (specified by the driver and / or the automatic speed control device).The states and variables listed here are conventionally output to the brake booster control device 10 by means of at least one sensor for determining the braking force of a possible actuation of a brake actuation element, such as a brake pedal. By forwarding the output states and / or variables via signals a3 and a4, the modulation device 14 can also take the forwarded states and / or variables into account when controlling the at least one hydraulic brake system component. Thus, the functioning of the at least one hydraulic brake system component can also be optimized with respect to the states and / or variables listed here.

[0042] The brake actuation state a3 can, for example, be a soft BLS signal indicating that the driver is (currently) braking (BLS_iBooster). A data volume of 1 bit is sufficient to transmit the brake actuation state a3. The brake pressure value a4 can also be communicated to the modulation device 14 using a comparatively small transmitted data volume, e.g., a data volume of 1 sw. This is done, for example, by an iBooster driver brake pressure signal (iBooster Driver Pressure, iBooster_Driver).

[0043] Furthermore, the at least one second information and / or control signal a1 to a7 that can be defined by the brake booster control device 10c can include information a5 relating to an active pressure buildup carried out by the brake booster without a driver braking request. Thus, whenever the brake booster carries out an active pressure buildup despite the driver not actuating the brake actuating element, the brake booster control device 10 can inform the modulation device 15 of this using information a5. This is possible using a transmitted data volume of just 1 bit (e.g., via an ActPressure signal).In this way, it is possible to prevent the modulation device 14 from interpreting the simultaneous detection of a non-actuation of the brake actuation element by the driver and a resulting brake pressure build-up in at least one brake circuit as a fault in a sensor and / or a data evaluation device of the modulation device 14. Since such a misinterpretation is conventionally often associated with a functional limitation of the modulation device 14, these misinterpretations and functional limitations, which occur comparatively frequently in the prior art, can be reliably avoided by forwarding the information a5. Optionally, the brake booster control device 10 can also output a verification signal a6 to the modulation device 14 before outputting the information a5, which indicates that the signal subsequently output by the brake booster control device 10 to the modulation device 14, such asThe information a5 is valid. Using a verification signal a6 (Replace pDriver from Pedal Stroke / Replace_pVor) of just 1 bit, a beneficial safety function can be implemented.

[0044] Furthermore, the at least one first information and / or control signal b1 to b9, which can be determined by means of the hydraulic control device 10c, can comprise wheel brake cylinder operating point information b3, brake pressure estimation information, brake pressure measurement information, maximum deceleration estimation information, friction coefficient information, and / or road gradient information. Typically, these estimated and / or measured values / quantities / information relating to an operating point of at least one wheel brake cylinder of the braking system, a wheel pressure present at at least one wheel brake cylinder, and / or a brake pressure / pre-pressure / circuit pressure in at least one brake circuit of the braking system are output to the modulation device 14 for controlling the at least one hydraulic brake system component.By forwarding the values / quantities / information listed here, the functionality of the brake booster control device 10 can also be optimized with regard to the forwarded values / quantities / information. A transmitted data volume of 1 sw is often sufficient for forwarding the values / quantities / information listed here. For example, the information on the estimated or measured maximum wheel pressure (maximum of wheel pressure) can thus be forwarded comparatively easily and quickly from the modulation device 14 to the brake booster control device 10 (pEstRadMax).

[0045] However, devices 10 and 14 may not only be designed to exchange information with each other. Likewise, at least one of devices 10 and 14 may also be designed to specifically trigger the other of the two devices 10 and 14 to perform a specific function, thereby achieving improved overall functionality of the two devices 10 and 14.

[0046] As described below using an example, the brake booster control device 10 can also control the modulation device 14 to effect a brake boost that would otherwise be carried out by means of the brake booster control device 10 / the brake booster: For example, the at least one second information and / or control signal a1 to a7 that can be determined by the brake booster control device 10c can include information a6 regarding a driver braking request that exceeds the maximum achievable boost of the brake booster and / or a request for hydraulic brake boosting by means of the at least one hydraulic brake system component. The brake booster control device 10 outputs, for example, as information a7, a brake booster failure signal or a brake booster limited signal (iBooster Pressure Limit Signal, Runout Pressure Signal) to the modulation device 14. Information a7 can also be output if the brake booster can no longer build up any further brake pressure, but the driver requests a brake pressure that cannot be achieved by the brake booster used as the sole auxiliary means.A transmitted data volume of 1 sw is sufficient as information a7. Thus, in the event of a functional impairment of the brake booster, in particular in the event of a brake booster failure, the existing situation can be detected by the modulation device 14 using a data protocol and at least partially compensated for by an active brake force assistance measure using at least one hydraulic brake system component. For example, the modulation device 14 can take the received information a7 into account when determining the at least one target operating mode of the at least one hydraulic brake system component such that hydraulic brake force amplification can be carried out using the at least one hydraulic brake system component.Thus, despite the impaired functionality or failure of the brake booster, the driver can still be assisted during vehicle deceleration by the brake pressure built up in at least one wheel brake cylinder by the at least one hydraulic brake system component. This ensures advantageous braking comfort even in the event of a brake booster failure.

[0047] The functioning of the brake booster can also be optimized by means of some first information and / or control signals b4 to b9 output by the modulation device 14 to the brake booster control device 10: The at least one first information and / or control signal b1 to b9, which can be defined by the hydraulic control device 14c, can also include vehicle standstill information b4 and / or a request b5 to reduce brake booster. For example, a 1-bit vehicle standstill signal (Vehicle_standstill signal) can be output to the brake booster control device 10 as information b4. A signal with a transmitted data volume of 1 bit (e.g., an ABS_allWheels signal) can also be transmitted for the request / permission b5 to reduce brake booster. In both cases, after receiving the signals b4 and b5, the brake booster control device 10 can (re)define the target brake booster mode such that the brake booster controlled by the brake booster control signal is controlled to reduce brake booster.Thus, in situations where the driver requests higher brake boost than required, for example, when the vehicle is stationary, when friction coefficients are low, and / or when ABS is activated on all wheels of the vehicle, the brake booster can be reduced. This reduces the energy consumption of the brake booster without reducing braking comfort for the driver. In particular, the vehicle's standstill, which can be reliably detected by the modulation device 14 and in which high brake pressures are not required, can be used to save a significant amount of energy. As soon as the vehicle is stationary, the brake booster can easily be increased again.

[0048] Accordingly, the brake boost can also be reduced in ABS mode to save a significant amount of energy. By reducing the brake boost in ABS mode, unwanted pedal movements can also be reliably prevented or limited. Thus, the advantageous communication between devices 10 and 14 also ensures improved braking comfort for the driver.

[0049] Furthermore, the at least one first information and / or control signal b1 to b9, which can be defined by means of the hydraulic control device 10c, can additionally include a permission b6 and / or a request b7 for brake boosting. The signal b6 can thus also be rewritten as a brake booster enable signal. For example, the brake booster control device 10 can be excited by the signal b6 to control the brake booster to actively build up pressure. A transmitted data volume of 1 bit is also sufficient for the signal b6. The signal b6 can also be an active pressure buildup control signal (ESP_Reduced signal), for example.

[0050] By means of the brake pressure build-up request b7, the wheel brake pressure present in at least one wheel brake cylinder of the vehicle equipped with devices 10 and 14 can be increased quickly and conveniently. Due to its deflection, the electrically controllable brake booster is better suited than a hydraulic brake system component designed as a pump at low circuit pressures to quickly, precisely, and conveniently build up / increase the brake pressure in at least one wheel brake cylinder. This is advantageous for many comfort and safety functions that are often present in an ESP system. This allows actuations such as a brake assist system, hill descent control, and / or roll-over mitigation to be carried out more quickly and conveniently.By designing a suitable data protocol and evaluating it, this can also be done with a high level of security.

[0051] As explained above, the interaction of devices 10 and 14 can reduce the energy consumption of a brake booster and / or allow the brake pressure buildup by the brake booster to be carried out more quickly and conveniently than with hydraulic brake pressure buildup. The data protocols and algorithms required for this purpose can be easily implemented in at least one of devices 10 and 14. Thus, improved braking comfort for the driver can be ensured at a low additional cost.

[0052] However, the interaction of devices 10 and 14 can also further improve the haptics of a brake actuation element (brake pedal). This is possible if hydraulic control device 14c is additionally configured to define volume displacement information b8 or b9 relating to a brake fluid volume to be displaced from a master brake cylinder and / or relating to a brake fluid volume returned in the master brake cylinder as the at least one first information and / or control signal b1 to b9.For example, after receiving volume shift information b8 regarding a brake fluid volume to be shifted from the master cylinder, which volume is requested by the modulation device 14, the brake booster control device 10 can redefine the target brake booster mode such that a corresponding actual volume of brake fluid is forced out of the master cylinder by means of an increased pressure exerted on at least one master cylinder piston and / or an increased displacement travel of the at least one master cylinder piston. A transmitted data volume of 4 bytes may be sufficient for the volume shift information b8.

[0053] Accordingly, volume shift information b9 relating to a brake fluid volume returned to the master cylinder, for example, by means of a pump, can also be output to the brake booster control device 10. In this case, the brake booster control device 10 can adapt the target brake booster mode to the volume shift information b9 such that, despite the additional brake fluid volume returned to the master cylinder, a standard / advantageous brake actuation / pedal feel is ensured for the driver. A transmitted data volume of between 8 bits and 16 bits is sufficient for the volume shift information b9.

Claims

[1] Brake booster control device (10) for an electrically controllable brake booster, with a first connection device (10a, 10b) by means of which the brake booster control device (10) can be connected to a vehicle bus system (12) such that at least one first signal (b1 to b9) transmitted via the vehicle bus system (12) can be received; and a brake booster control device (10c), by means of which a desired brake booster mode of the brake booster can be determined taking into account at least the at least one received first signal (b1 to b9) and a brake booster control signal corresponding to the determined desired brake booster mode can be output to the brake booster, so that the brake booster can be controlled by means of the brake booster control signal into an actual brake booster mode corresponding to the desired brake booster mode; characterized by, that by means of the first connection device (10a, 10b) at least one first information and / or control signal (b1 to b9) output by a modulation device (14) for at least one hydraulic brake system component to the vehicle bus system (12) can be received as the at least one first signal (b1 to b9), wherein the brake booster control device (10c) is designed, after receiving the at least one first information and / or control signal (b1 to b9), to define the target brake booster mode as the at least one first signal (b1 to b9), at least taking into account the at least one first information and / or control signal (b1 to b9). [2] Brake booster control device (10) according to claim 1, wherein by means of the brake booster control device (10c) at least one second information and / or control signal (a1 to a7) for the modulation device (14) can be additionally defined, which can be output in a targeted manner to the modulation device (14) by means of the first connection device (10a, 10b) via the vehicle bus system (12). [3] Brake booster control device (10) according to claim 2, wherein the at least one second information and / or control signal (a1 to a7) that can be determined by means of the brake booster control device (10c) is at least one status bit (a1) and / or a handshaking signal (a2). [4] Brake booster control device (10) according to claim 2 or 3, wherein the at least one second information and / or control signal (a1 to a7) which can be determined by means of the brake booster control device (10c) comprises a brake actuation state (a3), a brake pressure variable (a4), a braking distance variable, a desired vehicle deceleration and / or a desired braking torque. [5] Brake booster control device (10) according to one of claims 2 to 4, wherein the at least one second information and / or control signal (a1 to a7) which can be determined by means of the brake booster control device (10c) comprises information (a5) relating to an active pressure build-up carried out by means of the brake booster without a driver braking request. [6] Brake booster control device (10) according to one of claims 2 to 5, wherein the at least one second information and / or control signal (a1 to a7) which can be determined by means of the brake booster control device (10c) comprises information (a7) relating to a driver braking request exceeding a maximum achievable gain of the brake booster and / or a request for hydraulic brake boosting by means of the at least one hydraulic brake system component, so that the at least one hydraulic brake system component can be excited to hydraulic brake boosting by means of the modulation device (14) receiving the information (a7) relating to the driver braking request exceeding the maximum achievable gain of the brake booster and / or the request for hydraulic brake boosting. [7] Electrically controllable brake booster with a brake booster control device (10) according to one of the preceding claims. [8] Modulation device (14) for at least one hydraulic brake system component, with a second connection device (14a, 14b) by means of which the modulation device (14) can be connected to a vehicle bus system (12) in such a way that at least one second signal (a1 to a7) transmitted via the vehicle bus system (12) can be received; and a hydraulic control device (14c), by means of which at least one desired operating mode of the at least one hydraulic brake system component can be determined taking into account at least the at least one received second signal (a1 to a7) and at least one hydraulic control signal corresponding to the at least one determined desired operating mode can be output to the at least one hydraulic brake system component, so that the at least one hydraulic brake system component can be controlled by means of the hydraulic control signal into at least one actual operating mode corresponding to the at least one desired operating mode; characterized by , that by means of the hydraulic control device (14c) the at least one first information and / or control signal (b1 to b9) for the brake booster control device (10) according to one of claims 1 to 6 can additionally be determined, which can be output in a targeted manner to the brake booster control device (10) via the vehicle bus system (12) by means of the second connection device (14a, 14b). [9] Modulation device (14) according to claim 8, wherein the second information and / or control signal (a1 to a7) output by the brake booster control device (10) to the vehicle bus system (12) can be received as the at least one second signal (a1 to a7) by means of the second connection device (14a, 14b), wherein the hydraulic control device (14c) is designed, after receiving the second information and / or control signal (a1 to a7), to define the at least one desired operating mode as the at least one second signal (a1 to a7) at least taking into account the second information and / or control signal (a1 to a7). [10] Modulation device (14) according to claim 8 or 9, wherein the at least one first information and / or control signal (b1 to b9) that can be determined by means of the hydraulic control device (14c) is at least one status bit (b1) and / or a handshaking signal (b2). [11] Modulation device (14) according to one of claims 8 to 10, wherein the at least one first information and / or control signal (b1 to b9) which can be determined by means of the hydraulic control device (14c) comprises wheel brake cylinder operating point information (b3), wheel pressure estimation information, wheel pressure measurement information, brake pressure estimation information, brake pressure measurement information, maximum deceleration estimation information, friction coefficient information and / or road gradient information. [12] Modulation device (14) according to one of claims 8 to 11, wherein the at least one first information and / or control signal (b1 to b9) which can be determined by means of the hydraulic control device (14c) comprises vehicle standstill information (b4) and / or a request (b5) to reduce a brake booster, so that the brake booster control device (10), after receiving the vehicle standstill information (b4) and / or the request (b5) to reduce the brake booster, is designed to determine the desired brake booster mode such that the brake booster can be excited to reduce the brake booster. [13] Modulation device (14) according to one of claims 8 to 12, wherein the at least one first information and / or control signal (b1 to b9) which can be determined by means of the hydraulic control device (14c) comprises a permission (b6) and / or a request (b7) to increase the brake force booster, so that the brake booster control device (10), after receiving the permission (b6) and / or the request (b7) to increase the brake force booster, is designed to set the target brake booster mode such that the brake booster can be excited to increase the brake force booster. [14] Modulation device (14) according to one of claims 8 to 13, wherein the at least one first information and / or control signal (b1 to b9) which can be determined by means of the hydraulic control device (14c) comprises volume displacement information (b8, b9) relating to a brake fluid volume to be displaced from a master brake cylinder and / or relating to a brake fluid volume fed back into the master brake cylinder, so that the brake booster control device (10) is designed, after receiving the volume displacement information (b8, b9), to determine the desired brake booster mode such that the brake booster can be excited to a corresponding increase in the brake force boost. [15] Hydraulic unit with at least one hydraulic brake system component and a modulation device (14) for the at least one brake system component according to one of claims 8 to 14. [16] Braking system for a vehicle with a brake booster control device (10) according to one of claims 1 to 6 or a brake booster according to claim 7; and a modulation device (14) for at least one brake system component of the brake system according to one of claims 8 to 14 or a hydraulic unit according to claim 15.

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