WO2018130481A1

WO2018130481A1 - Braking system for a motor vehicle

Info

Publication number: WO2018130481A1
Application number: PCT/EP2018/050325
Authority: WO
Inventors: Harald Biller; Jochen Zimmermann; Rüdiger BRIESEWITZ; Jochen Beuss; Christian Courth; Dieter Dinkel; Stefan Drumm; Robert Grimm; Roland Caspari
Original assignee: Continental Teves Ag & Co. Ohg
Priority date: 2017-01-11
Filing date: 2018-01-08
Publication date: 2018-07-19
Also published as: DE102017222450A1

Abstract

The invention relates to a brake system for a motor vehicle, having hydraulically actuatable wheel brakes (8a-8d), which are associated with wheels of a first and a second vehicle axle, an electrically actuatable inlet valve (6a-6d) and an electrically actuatable outlet valve (7a-7d) for each wheel brake (8a-8d), a first electrically controllable pressure-providing device (5), which is separably hydraulically connected to a brake supply line (13) by means of a first separating valve (26), to which brake supply line the wheel brakes (8a-8d) are connected, a second electrically controllable pressure-providing device (2), which is separably hydraulically connected to the brake supply line (13) by means of a second separating valve (23), wherein an electrically actuatable axle separation valve (40) is arranged in the brake supply line (13) in such a way that, when the axle separation valve is closed, the brake supply line (13) is hydraulically divided into a first and a second line section (13a, 13b), wherein the first line section (13a) is hydraulically connected to the wheel brakes (8a, 8b) of the second vehicle axle (HA) and to the second pressure-providing device (2) and the second line section (13b) is hydraulically connected to the wheel brakes (8c, 8d) of the first vehicle axle (VA) and to the first pressure-providing device (5), a first electrical device (100), which controls the first pressure-providing device (5), a second electrical device (110), which controls the second pressure-providing device (2), a single-circuit master brake cylinder (80), which can be actuated by means of a brake pedal (1) and which is hydraulically connected to the brake supply line (13), and a simulation device (3), which is operatively connected to the master brake cylinder (80).

Description

Brake system for a motor vehicle

The invention relates to a brake system for a motor vehicle according to the preamble of claim 1.

From DE 10 2013 217 954 AI a brake system with two electrically controllable pressure sources and a tandem master cylinder for a motor vehicle with four hydraulically actuated wheel brakes is known. The brake system comprises in addition to individual wheel inlet and exhaust valves a Kreistrennventil and four separating valves for the separation of the Tan ^¬ the master brake cylinder and the electrically controllable

Pressure sources from the intake valves. The circular selector valve is designed to be normally closed and separates the brake system into two brake circuits during normal operation of the brake system, wherein the two front wheel brakes are assigned to the first brake circuit and the two rear wheel brakes to the second brake circuit. In the first brake circuit, brake pressure is built up exclusively from the first pressure source and in the second brake circuit exclusively in front of the second pressure sources. The tandem master cylinder comprises two pressure chambers, each of the pressure chambers is assigned to exactly one of the brake circuits. Furthermore, the brake system ^¬ includes a central control unit, a first pressure source associated with the first control unit and the second pressure source associated second control and Re ^¬ geleinheit. The first and second control and regulating units are each used to control the corresponding pressure source. By means of the central control and regulating unit, the Kreistrennventil is actuated. Further details about which of the three control units the other valves operated or. are not disclosed in DE 10 2013 217 954 AI. Also, the document does not mention how the electrical allocation and power supply of the three control and gel units and their associated components is executed.

It is an object of the present invention, bereitzu ^¬ provide a suitable for highly automated driving Brake system which is simple in construction and therefore inexpensive, but which provides the availability necessary for the highly automated driving, as high as possible without intervention of the driver. However, the brake system should be able to be operated in a so-called last fallback by the power of the driver.

This object is achieved by a brake system according to claim 1. The invention is based on the idea to provide a brake system with hydraulically actuated wheel brakes which are associated with wheels of a first vehicle axle and wheels of a second vehicle axle, an electrically actuated intake valve per wheel brake and an electrically actuated exhaust valve per wheel to set wheel individual brake pressures, a first electrically controllable Pressure supply device which is hydraulically connected separably via a first isolation valve to a brake supply line to which the wheel brakes are connected, a second electrically controllable pressure supply means which is hydraulically connected via a second isolation valve to the brake supply line, wherein arranged in the brake supply line, an electrically actuated axial disconnect valve is that the brake supply line hydraulisch in a first and a second line section when the axial disconnect valve is closed h is separated, wherein the first line section is hydraulically connected to the wheel brakes of the second vehicle axle or their inlet valves and the second line section with the wheel brakes of the first vehicle axle or their Inlet valves is hydraulically connected. In this case, the second pressure-providing device is hydraulically connected via the second separating valve to the first line section and the first pressure-providing device is hydraulically connected via the first separating valve to the second line section. The brake system further comprises a first electrical ^¬ A device with electrical and / or electronic elements, which drives the first pressure supply device and a second electrical device having electrical and / or electronic elements, which drives the second pressure-supplying ^¬ provision device. For a driver-actuated fallback level, a single-circuit master cylinder which can be actuated by means of a brake pedal and which is hydraulically connected to the brake supply line and which is operatively connected to a simulation device is furthermore provided.

The invention offers the advantage that the brake system is simple and compact, yet it is suitable both for highly automated driving and for direct hydraulic actuation of the wheel brakes by the driver.

Preferably, the first and the second electrical device are electrically independent of each other, so that an electrical or electronic fault in one of the electrical devices does not lead to a failure of both electrical devices.

The two electrical devices are electrically independent of each other in the sense that failure of the first electrical device does not cause failure of the second electrical device, and vice versa, i. the two electrical devices are galvanically isolated.

The inlet and outlet valves are preferably of the second controlled electrical device which also controls the second pressure supply device. This offers the advantage that the brake system has a high availability with regard to the provision of brake functions in which all wheel brakes, possibly with different wheel brake pressures, are actuated in order, for example, to ensure a short braking distance and to maintain steerability of the motor vehicle. Thus, in a fault-free condition of the brake system wheel-individual wheel brake pressures can be adjusted by the first electrical means by means of the first Druckbereitstel ^¬ treatment device provides a (central) brake pressure and the second electrical device by means of the intake and exhaust valves modulates the wheel wheel individual pressures. But device also in case of failure of the first Druckbereitstellungs- or the first electrical device can be adjusted on each individual wheel wheel brake by the second electrical device by means of the second Druckbe ^¬ riding position means and the intake and exhaust valves performs braking with wheel-individual wheel brake pressures.

Preferably, the first pressure supply device is driven exclusively by the first electrical device and the second pressure supply device and the inlet and outlet valves are preferably driven exclusively by the second electrical device. Thus, for further redundancy in the components, e.g. can be dispensed with double controllable valves with two independent valve coils or on a pressure supply device with two electrically independent electric motors.

Preferably, in the braking position, a first electrical partition and a second electrical partition are provided, wherein the first and the second electrical partition are electrically independent of each other. The first pressure delivery device and the first electrical device is associated with or associated with the first electrical partition, and the second pressure providing device, the second electrical device and the inlet and outlet valves are associated with or belong to the second electrical partition.

The first isolation valve is preferably controlled by means of the first electrical device and / or supplied with electrical energy. So can in case of failure of the second

Pressure supply device, the first electrical device to open the first isolation valve and actuate the wheel brakes by means of the first pressure supply device. In order to dispense with a double controllable valve and other control lines, the first isolation valve is particularly preferably driven exclusively by the first electrical device or supplied with electrical energy. Particularly preferably, the first isolation valve belongs to the first electrical partition or is assigned to this. The second isolation valve is preferably activated by means of the second electrical device and / or supplied with electrical energy. So can in case of failure of the first

Pressure supply device, the second electrical device to open the second isolation valve and actuate the wheel brakes by means of the second pressure supply device. In order to dispense with a double controllable valve and other control lines, the second isolation valve is particularly preferably driven exclusively by the second electrical device or supplied with electrical energy. Particularly preferably, the second isolation valve belongs to the second electrical partition or is assigned to it.

The first and the second isolation valve are preferably designed to be normally closed, in order, for example, in the event of a failure of all electrical .

b

Energy sources of the brake system to allow the penetration of the driver to the wheel brakes without pressure medium is moved to one of the pressure supply device or flows into the pressure medium reservoir.

Preferably, the brake system comprises a first pressure sensor, which is assigned to the first pressure supply device, and a second pressure sensor, which of the second

Pressure supply device is assigned.

Preferably, the first electrical device electrical and electronic components for signal processing or evaluation of the first pressure sensor for the first Druckbe ^¬ riding provision means and the second electrical device comprises electrical and electronic components for Sig ^¬ nalbearbeitung or evaluation of the second pressure sensor for the second pressure supply device comprises.

Preferably, the first pressure sensor, advantageously exclusively, connected to the first electrical device and is, advantageously exclusively, counted from the latter ^¬ and the second pressure sensor is advantageously exclusively, connected to the second electrical device and advantageously exclusively, this evaluated.

The pressure chamber of the master brake cylinder is preferably hydraulically connected to the brake supply line via a third isolation valve and a fourth isolation valve which is hydraulically connected downstream of the third isolation valve. Thus, the hydraulic connection between master cylinder and brake supply line can be separated in two independent ways, namely by two independent valves. Particularly preferably, third and fourth isolation valve are normally open to open at Failure of all electrical energy sources of the brake system to allow the penetration of the driver on the wheel brakes.

According to one embodiment of the invention, the third

Disconnect valve controlled by the first electrical device and / or supplied with electrical energy, while the fourth isolation valve is controlled by means of the second electrical direction and / or ^¬ supplied with electrical energy. Alternatively, it is preferred that the fourth isolation valve is controlled and / or supplied with electrical energy by means of the first electrical device, while the third ^isolation valve is actuated by means of the second electrical device and / or supplied with electrical energy. To dispense with double controllable valves and other Ansteuer ^¬ lines, particularly preferably the respective (third or fourth) isolation valve is particularly preferably driven exclusively by the respective electrical device or supplied with electrical energy. Particularly preferably, the respective isolation valve belongs to the corresponding electrical partition or is assigned to this, which also belongs to the electrical control device which controls the isolation valve. Alternatively, it is preferred that the pressure chamber of the main ^¬ brake cylinder is hydraulically connected via a single master brake cylinder-separating valve with the brake supply line. In this case, the master cylinder isolating valve is designed to be double controllable, advantageously the master brake cylinder isolating valve comprises two independent valve coils for actuation (of the valve). Particularly preferably, the Hauptbremszylin ^¬ der-separating valve is controlled by means of both the first electrical device and the second electrical device and / or supplied with electrical energy. The pressure chamber of the master cylinder is preferably hydraulically connected to the first line section of the brake supply line.

The second pressure supply device preferably comprises a suction connection, which is connected to a pressurized medium storage container which is under atmospheric pressure, and a pressure connection, wherein for adjustment or regulation of the pressure provided by the second pressure supply device

Pressure overflow valve is provided, via which the pressure port is hydraulically connected to the suction port. That is, the spill valve of the second pressure READY ^¬ averaging means is connected in parallel. This offers the advantage that different types of pressure sources can be used for the two pressure supply devices. While the first pressure supply device should be designed for precise and dynamic adjustment or adjustment of the pressure provided by it, the second pressure supply device can be designed more cost-effective, since a precise and dynamic adjustment of the pressure provided by it by means of the overflow valve is possible. Particularly preferably, the overflow valve is designed to be normally open. This is possible because the second pressure supply device can be separated from the brake supply line via the second separating valve, in order to prevent a flow of pressure medium to the pressure medium reservoir. Particularly preferably, the overflow valve is designed to be adjustable in order to ensure precise adjustment or regulation of the pressure provided by the second pressure supply device.

The overflow valve is preferably activated by means of the second electrical device and / or with electrical Energy supplied. So can in case of failure of the first

Pressure supply device set the second electrical device by means of the second pressure supply device and the spill valve precise pressure curves at the wheel brakes. In order to dispense with a double controllable valve and other control lines, the spill valve is particularly preferably driven exclusively by the second electrical device or supplied with electrical energy. Particularly preferably, the overflow valve belongs to the second electrical partition or is assigned to it.

The second pressure supply device is preferably formed by a piston pump, particularly preferably by a radial piston pump. This type of pump, tried and tested for many years in automotive brake systems, can be used in the

Brake system can be used, since by means of the overflow valve, a pressure relief or pressure reduction can be performed with sufficient speed and precision to provide the above-mentioned main brake functions in case of failure of the first pressure supply device can. Piston pumps are inexpensive to produce and are based on known technologies, so that their use also represents a very low development risk for the brake system. Preferably, the axial disconnect valve is normally open, so that the actuation of the / all wheel brakes by means of

Master cylinder or one of the pressure supply facilities, the axis separating valve does not need to be controlled. The axis separating valve is preferably by means of the first

electrical device driven and / or supplied with electrical energy. So can in case of failure of the second

Pressure supply device or the second electrical device, the first electrical device by means of the first Pressure supply device and the axial release valve act on the wheel brakes with achsindividuelle brake pressures. As a result, the locking order of the axles and the steerability can be maintained. In order to dispense with a double-check-controllable valve as well as further drive lines, which is particularly preferred Achstrennventil eventually driven from ^¬ of the first electrical device or supplied with electric power. The axial disconnect valve particularly preferably belongs to the first electrical partition or is assigned to it.

The Achstrennventil is arranged such that, when ge ^¬ schlossenem Achstrennventil the brake supply line is hydraulically separated into a first line portion and a second line portion, the first line ^¬ portion with the second pressure supply device and the inlet valves of the wheel brakes of the rear axle of the

Motor vehicle is connected and the second line section is connected to the first pressure supply device and the inlet valves of the wheel brakes of the front axle of the motor vehicle. Thus, in the event of a failure in the second electrical partition, the axle brake pressure at the rear axle can be kept constant by the first electrical device and modulated at the front axle.

According to one embodiment of the invention, the simulation device is hydraulically connected to the master brake cylinder, in which connection a parallel connection of two simulator release valves is arranged, wherein one of simulator latorfreigabeventile is controlled by the first electrical device and / or supplied with electrical energy, while the other of Simulatorfreigabeventile is controlled by the second electrical device and / or supplied with electrical energy. Particularly preferred are the two Simulatorfreigabeventile normally closed executed, for example, in case of failure of all electrical energy sources of the brake system to allow the penetration of the driver to the wheel brakes, without pressure medium is moved into the simulation device. To be able to dispense with double controllable valves and other control lines, the one of the simulator release valves is particularly preferably controlled exclusively by means of the first electrical device and / or supplied with electrical energy, while the other of the simulator release valves exclusively controlled by the second electrical device and / or with electrical energy is supplied.

Alternatively, the simulation device is hydraulically connected to the master brake cylinder, wherein a single, more preferably normally closed, Simu ^¬ latorfreigabeventil is disposed in this connection. The simulator release valve is designed to be double controllable and is by means of both the first electrical device and the second

controlled electrical device.

According to a development of the invention, the master brake cylinder or the simulation device is assigned at least two sensors for detecting a respective driver brake request variable. It is one of the sensors with the first electrical

Device connected and is evaluated by this, and the other of the sensors is connected to the second electrical device and is evaluated by this. Thus, a driver brake request can be independently recognized by each of the electrical devices and braking can be carried out by means of the corresponding pressure-limiting device. In order to reduce costs and redundancy (eg connecting lines), the two sensors are particularly preferably each connected exclusively to the corresponding electrical device and are evaluated by this.

To face a zelfehler to increase the availability of the braking system A ^¬ further, preferably the first electrical device from a first source of electrical energy supplied and supplies the second electric device from a second electric power source which is independent of the first electrical energy source. The first energy source is particularly preferably part of the first electrical partition, the second energy source is part of the second electrical partition. Advantageously, the first electrical energy source supplies the first electrical partition, ie all electrical components of the first electrical partition, with electrical energy, while the second electrical energy source supplies the second electrical partition, ie all electrical components of the second electrical partition, with electrical energy.

Preferably, a wheel speed sensor is provided for each of the wheel brakes, wherein the wheel speed sensors are connected to the second electrical device and are evaluated by the latter. Thus, the second electrical device can set the wheel-specific brake pressures in accordance with the situation. To reduce costs and redundancy (eg connecting lines), the wheel speed sensors are particularly preferably connected exclusively to the second electrical device and are evaluated by the latter. The wheel speed sensors particularly preferably belong to the second electrical partition. Preferably, a driving dynamics sensor is provided, which is connected to the first electrical device and is evaluated by this. Thus, the first electrical device can adjust the axle-specific brake pressures in accordance with the situation. To reduce costs and redundancy (eg connecting cables) the driving dynamics sensor is particularly preferably exclusively connected to the first electrical device and is evaluated by this. The vehicle dynamics sensor system particularly preferably belongs to the first electrical partition.

According to one embodiment of the invention, a second wheel speed sensor is provided for each of the wheel brakes, the second Raddrehzahlsensoren the first electrical partition belongs or is associated and, in particular exclusively, connected to the first electrical device and are evaluated by this, the control quality of to increase axle-specific brake pressure. To reduce costs and redundancy (e.g., interconnections), the second wheel speed sensors are most preferably exclusively connected to and evaluated by the first electrical device.

According to one embodiment of the invention, the second

Pressure supply device by a piston pump, advantageously a radial piston pump, formed with a suction connection and a pressure port, wherein the pressure connection via the overflow valve to the suction port is hydraulically connected. The overflow valve is thus connected in parallel to the second pressure supply device.

Preferably, the first pressure supply device by a cylinder-piston assembly with a hydraulic

Pressure chamber formed, the piston by an electromechanical actuator for a brake pressure build-up and for a

The brake pressure reduction is reduced.

The brake system preferably comprises a pressure medium reservoir which is under atmospheric pressure. The brake system preferably comprises at least four hydraulically actuable wheel brakes.

Preferably, the brake system per wheel brake comprises an inlet valve and an outlet valve for adjusting wheel-specific brake pressures, which from the brake supply pressure in the

Are derived in the non-actuated state, the intake valves, the brake supply pressure to the wheel brakes and the exhaust valves block a flow of pressure fluid from the wheel brakes.

Particularly preferably, all the exhaust valves are connected via a ge ^¬ my same hydraulic connection with the pressure at atmospheric pressure fluid reservoir.

Preferably, in a fault-free condition of the brake system, the first electrical device by means of the first leads Druckbe ^¬ riding provision means by actuation of the wheel brakes, wherein the second electrical device by means of the intake and exhaust adjusting wheel-individual wheel brake pressures.

Preferably, in the event of a failure in the first electrical partition, e.g. a failure of the first pressure supply device or the first electrical energy source or the first electrical device, the second electrical

Device by means of the second pressure supply device and the intake and exhaust valves braking with rad ^¬ individual wheel brake by. In the event of a failure in the second electrical partition, for example a failure of the second pressure supply device or the second electrical energy source or the second electrical device, the first electrical device preferably leads by means of the first pressure supply device and the axle disconnect valve braking with achsinduellen wheel brake.

In this case, to maintain the maneuverability and stability of the vehicle is particularly preferably the axis ^¬ brake pressure at the rear axle held constant while the Achsbremsdruck is modulated on the front axle.

The invention offers the advantage that even after a serious error, such as failure of one of the electrically controllable pressure supply devices or one of the electrical devices, the most important braking functions can be performed autonomously or by an autopilot function, in particular to build up delay, the blocking order of the vehicle axles to maintain and prevent destabilization at high delays, as well as to maintain steerability. For this purpose, wheel-individual and at least individual brake circuit-specific pressures are necessary and the setting of respective precise brake pressure curves including pressure build-up, pressure reduction and pressure maintenance. The brake system is thus particularly suitable for the realization of highly automated driving functions, but offers a driver-actuated rear ^¬ fallebene. The invention also offers the advantage that the brake system even if one of the two redundant electric pressure providing means, for example due to a failure of its associated source of electric power or its associated electric driving device or a mechanical error or leakage in the pressure supply ^¬ positioning device itself, can maintain the main residual braking functions, but while the number of redundantly running components is minimized. Thus, the master cylinder can be executed in a single circle. Also need neither the sensors nor the wheel pressure control valves (intake and exhaust valves) are redundant.

The brake system according to the invention is therefore particularly suitable for the realization of highly automated driving functions.

Further preferred embodiments of the invention will become apparent from the subclaims and the following description with reference to figures.

It shows schematically

Fig. 1 shows an embodiment of an inventive

Brake system.

Fig. 1 shows schematically an embodiment of a brake system according to the invention for a motor vehicle with four hydraulically actuated wheel brakes 8a, 8b, 8c, 8d. For example, the wheel brake 8a is associated with the left rear wheel (RL), the wheel brake 8b with the right rear wheel (RR), the wheel brake 8c with the left front wheel (FL) and the wheel brake 8d with the front right wheel (FR). The wheel brakes 8a, 8b are assigned to the rear axle HA and the wheel brakes 8c, 8d to the front axle VA. The brake system comprises a means of a brake pedal 1 be ^¬ tätigbaren, single-circuit skin brake cylinder 80, connected to the master cylinder 80, hydraulic simulation ^¬ means 3, a first electrically controllable pressure ^¬ provision device 5, a second electrically controllable pressure supply device 2, an under-atmospheric pressure medium reservoir 4, wheel-individual

Brake pressure modulation valves, which are designed as an intake valve 6a-6d and an exhaust valve 7a-7d per wheel brake, a first electronic control unit 12 and a second electronic control and regulating unit 112. The electronic control units serve, for example, for controlling the electrically actuated components of

Brake system for powering electrical components of the brake system and / or for evaluating signals from sensors of the brake system, which will be explained in more detail below.

The first electrically controllable pressure supply device 5 is designed as a hydraulic cylinder-piston arrangement (or a single-circuit electro-hydraulic actuator (linear actuator)) whose piston 36 can be actuated by a schematically indicated electric motor 35 with the interposition of a rotationally-translational gear 39 likewise shown schematically. in particular can be moved back and forth to build up a pressure in a pressure chamber 37 and. The piston 36 limits the pressure chamber 37 of the Druckbereitstel ^¬ lling device 5. To control the electric motor, a rotor position of the electric motor 35 detected, only sche ^¬ matically indicated rotor position sensor 44 is provided.

To the pressure chamber 37 of the first electrically controllable pressure supply device 5, a system pressure line section 38 is connected. The line section 38 is connected via an electrically actuated, preferably normally closed, first isolation valve 26 with a brake supply line 13, via which all input terminals of the inlet ^¬ valves 6a-6d are connected to the pressure chamber 37 of the first electrically controllable pressure supply device 5. By the first isolation valve 26, the hydraulic connection between the pressure chamber 37 of the first electrically controllable pressure supply device 5 and the brake supply line 13 (and thus the input ports of the intake valves 6a-6d) controlled open and shut off. , ₀

Pressure chamber 37 is, regardless of the operating state of the piston 36, connected via a (suction) line 42 to the pressure medium reservoir 4. In line 42 a closing in the direction of the pressure medium reservoir 4 check valve 53 is arranged. A suction of pressure medium in the pressure chamber 37 is thus possible by a return of the piston 36 with the separating valve 26 closed. The cylinder-piston assembly 5 has no sniffer holes. The first pressure supply device 5 is a

high-performance printing plate, in the error-free

Brake system realizes the normal brake function with maximum comfort and maximum dynamics.

The second electrically controllable pressure supply device 2 is advantageously designed as a two-circuit Ra ^¬ dialkolbenpumpe whose two printed pages are connected together ^¬ . A single-circuit radial piston pump is also conceivable. It has a suction port 28 which is connected via a hydraulic connection 41 to the pressure medium ^¬ reservoir 4 in connection, and a pressure port 27. The pressure port 27 of the second pressure provisioning ^¬ device 2 is connected to the brake supply line 13 so that the input terminals of the intake valves 6a 6d are connected to the pressure port 27 of the second pressure supply device 2.

The second pressure supply device 2 is assigned to a spill valve 32, the control of a

Pressure limitation and pressure reduction can realize. For this purpose, the pressure port 27 of the second pressure supply device 2 via the overflow valve 32 to the suction port 28 and thus the pressure medium reservoir 4 is connected. The overflow valve 32 is designed to be normally open, and advantageously analog adjustable executed. By means of the overflow valve 32, the pressure provided by the second pressure supply device 2 for the wheel brakes can be limited or reduced. According to the example, a parallel connection of the normally open, analogously controllable overflow valve 32 and a pressure medium reservoir 4 to closing check valve 63 is arranged between the second Druckbereitstel ^¬ treatment device 2 and the pressure fluid reservoir 4.

The second pressure supply device or piston pump 2 is also associated with a (second) isolation valve 23, which is arranged hydraulically in series with the overflow valve 32. The second isolation valve 23 is designed to be normally closed.

If necessary, the separating valve 23 can be closed in order to avoid a pressure reduction / pressure medium discharge from the brake supply line 13 via the overflow valve 32 into the pressure medium reservoir 4.

According to the embodiment, the isolation valve 23

arranged hydraulically in series with the second pressure ^{supply ¬ device} 2. Correspondingly, the second pressure ^¬ providing apparatus 2 via the (second) release valve 23 is hydraulically connected to the brake supply line 13 and with the first conduit section 13a.

The brake pedal operable master cylinder 80 is designed as a single circuit and thus comprises a single hydraulic pressure chamber 88, which is bounded by a master brake cylinder piston 89 which is mechanically connected to the brake pedal 1. The master cylinder 80 or its pressure chamber 88 is connected via a hydraulic connection 85 to the brake supply line 13, advantageously the first line section 13a. In the hydraulic connection 85, ie between master brake cylinder 80 and brake supply line 13, a third isolation valve 81 and a fourth isolation valve 82 downstream of the third isolation valve are arranged. The separation ^¬ valves 81, 82 are connected in series. Third and fourth isolation valve 81, 82 are designed to be normally open.

Piston rod 24 couples the pivotal movement of the brake pedal 1 as a result of a pedal operation with a translational movement of the master brake cylinder piston 89, whose actuation travel is detected by a preferably redundantly designed displacement sensor 25. As a result, the corresponding piston travel signal is a measure of the brake pedal actuation angle. It represents a braking request of a driver. To the driver's braking requirement, a further sensor 20 is provided, which detects an independent piston stroke of the physical quantity which character- the driver's braking intention, cha ^¬. This can be eg a force sensor or a pressure sensor.

Simulation device 3 has in a housing a simulator piston 31, which separates a hydraulic chamber 34 from a simulator rear chamber 30. Simulator piston 31 is supported by an elastic element 33 arranged in the simulator rear chamber 30 (eg simulator spring) on the housing. Simulation ^{¬ device} 3 and its hydraulic chamber 34 is hydraulically connected to the pressure chamber 88 of the skin brake cylinder 80. In the hydraulic connection between master brake cylinder 80 and simulation device 3, a first simulator release valve 83 and a second simulator release valve 84 are arranged. The simulator enable valves 83, 84 are connected in parallel. The Simulatorfreigabeventile 83, 84 are executed normally closed. The simulation device 3 can be switched on and off by means of the simulator release valves 83, 84. The simulation device 3 gives the driver a pleasant brake pedal feel when at least one of the isolation valves 81, 82 is closed and at least one of the simulator release valves 83, 84 is open.

The brake system thus includes additional hydraulic penetration (by the driver) as a second fallback level in the event of a double fault, e.g. a failure of first and second pressure providing means 2, 5.

As already mentioned, the brake system comprises per each hydraulically actuable wheel brake 8a-8d an inlet valve 6a-6d and an outlet valve 7a-7d, which are hydraulically interconnected in pairs via center connections and connected to the wheel brake 8a-8d. The inlet valves 6a-6d are each connected in parallel with a brake supply line 13 to the opening, unspecified check valve. The off ^¬ gear connections of the exhaust valves 7a-7d are connected via a ge ^¬ my same return line 14 with the pressure fluid supply reservoir. 4 The input ports of all inlet valves 6a-6d can be supplied by the brake supply line 13 with a pressure of the first pressure supply ^{¬ device} 5 or, for example, in case of failure of the first pressure supply device, from the second pressure supply device 2, or, for example in case of failure of both pressure supply device 2, 5, is provided by the master cylinder 80. In the brake supply line 13, an electrically actuated, advantageously normally open Achstrennventil 40 is arranged, through which the brake supply line 13 in a first line section 13 a, which (for example via the second separating valve 23) with the second Druckbereitstellungs- Device 2 is connected, and a second line section 13 b, which (for example, via the first isolation valve 26) is connected to the first pressure supply device 5, can be separated. Here, the first pipe portion 13a is hydraulically connected to two of the intake valves, namely, the intake valves 6a and 6b, and the second pipe portion 13b is hydraulically connected to the remaining intake valves, namely, the intake valves 6c and 6d. By closing the Achstrennventils 40, the brake system is thus hydraulically separated or split into two (partial) brake circuits I and II. In the first brake circuit I, the second pressure ^{supply device} 2 is connected to only the wheel brakes 8a and 8b of the rear axle, and in the second brake circuit II the first pressure supply device 5 is connected to only the wheel brakes 8c and 8d of the front axle.

The brake system comprises each brake circuit I or II a pressure sensor ^¬ : a first pressure sensor 19, which of the first

Pressure supply device 5 is assigned, and a second pressure sensor 49, which is associated with the second pressure supply device 2. Advantageously, the pressure sensors are connected close to the respective pressure supply device, which is advantageous for operation and self-diagnosis.

A pressure relief of the brake system or the wheel brakes in the release position is ensured by the Schnüffelloch in the master cylinder 80. According to the example, the brake system for leakage monitoring comprises a level measuring device 50 for determining a pressure medium level in the pressure medium reservoir 4. According to the example, the brake system comprises an electric parking brake (EPB) on the wheels of the rear axle HA. This can be integrated in the hydraulic wheel brakes, so-called integrated electric parking brake (IPB).

Each wheel, for example, a first wheel speed sensor and an independent second wheel speed sensor (or a redundant wheel speed sensor) assigned (not shown in detail in Fig. 1), the signals for brake control functions with wheel-individual brake pressures, eg for anti-lock control functions (ABS), are needed. The first wheel speed sensors are shown schematically as block 56 and the second wheel speed sensors as a block 66. The brake system remains for example in accordance with a driving dynamics sensor system ^¬ 60 is connected or comprises such. The driving dynamics sensor 60 comprises at least one measuring device for detecting one or more of the following variables:

• longitudinal acceleration, in particular vehicle longitudinal acceleration;

• lateral acceleration, in particular Fahrzeugquerbeschleu ^¬ nigung;

Yaw rate;

• Steering angle.

According to the example, the components 2, 5, 6a-6d, 7a-7d, 32, 23, 40 and 26 (and the sensors 19, 49) are arranged in a first module, eg in a first hydraulic control unit HCU1, during the master brake cylinder 80 with the simulation device 3 and the valves 81-84 (and the sensors 25, 20) is arranged in a separate, second module 200, eg in a second hydraulic control unit. The hydraulic control unit HCU1 is associated with the first electronic control unit (ECU) 12, which is shown very schematically. The first module (HCU1) and first ECU 12 are advantageously designed in known manner as a first electro-hydraulic unit (HECU).

The second hydraulic control unit 200 is assigned its own, the second electronic control unit (ECU) 112. These preferably form a second unit, namely a second electro-hydraulic unit (HECU).

Alternatively, an arrangement of the components 2, 3, 5, 80, 6a-6d, 7a-7d, 32, 23, 40, 26 and 81-84 in a common module, i. in a common hydraulic control unit (HCU) conceivable. It may then be associated with an electronic control unit (ECU) or several electronic control units (ECU).

To supply the brake system with electrical energy, a first electrical energy source 57, for example, a first electrical system, and one of the first energy source independent, second elekt ^¬ cal energy source 67, eg a second electrical system, are provided.

To control the brake system, a first electrical device 100 with electrical and / or electronic

Elements (e.g., microcontrollers, power parts, valve drivers, other electronic components, etc.) and a second electrical device 110 having electrical and / or electronic elements (e.g., microcontrollers, power parts, valve drivers, other electronic components, etc.). The first electrical device 100 and the second electrical device 110 are electrically independent. The first electrical device 100 controls the first one

Pressure supply device 5 on, the second electrical Device 110 controls the second pressure ^{supply ¬} device.

The intake and exhaust valves 6a-6d, 7a-7d are driven by the second electrical device 110.

For electrical connection, connection and supply of the individual electrical or electrically operable, controllable, evaluable or similar. Components of the brake system, for example, a first electrical partition A and a second electrical partition B are provided, wherein the first and the second electrical partition are electrically independent of each other. In the figures, those electrical components associated with the first electrical partition A are indicated by an arrow A, while those electrical components associated with the second electrical partition B are indicated by an arrow B are marked.

The first pressure supply device 5 and the first electrical device 100 are assigned to the first electrical partition A or belong to this, and the second pressure supply device 2, the second electrical

Means 110 and the inlet and outlet valves 6a-6d, 7a-7d are associated with or belong to the second electrical partition. The first isolation valve 26 is, advantageously ^¬ finally, driven by the first electrical device 100 and supplied with energy. Isolation valve 26 belongs to the first electrical partition A. The axial disconnect valve 40 is likewise actuated, advantageously exclusively, by the first electrical device 100 or supplied with energy. Axial disconnect valve 40 belongs to the first electrical partition A.

The overflow valve 32 and the second isolation valve 23 are, advantageously exclusively, driven by the second electrical device 110 or supplied with energy. The valve 23, 32 thus belongs to the second electrical partition B.

The third isolation valve 81 is for example in accordance with exclusively driven vorteilhaf ^¬ ingly from the first electrical device 100, while the fourth cut-off valve 82, by way of advantageous ^¬ legally exclusively, is driven by the second electric device 110th Isolation valve 81 thus belongs to the first partition A, separating valve 82 of the second partition B. A reverse assignment / control is also possible.

Simulator release valve 83 is for example in accordance with, Advantageous ingly exclusively, driven by the first electric device 100 while simulator release valve 84, part way only legally driven before ^¬ from the second electrical device 110th A reverse assignment / control is also possible. Simulator release valve 83 thus belongs to the first partition A, simulator release valve 84 of the second partition B.

By way of example, the first electrical energy source 57 supplies the electrical partition A with energy and the second electrical energy source 67 supplies the electrical partition B.

The first electrical device 100 and thus the partition A is also advantageously associated with one of the sensors 20, 25 for detecting braking demand, for example the sensor 20. The other of the sensors for detecting brake demand, for example the sensor 25, is assigned to the other, ie the second electrical device 100 or the partition A. The electrical and / or electronic elements of one of the electrical devices 100 or 110 are distributed to the two electronic control and regulation units 12, 112, for example. The electrical equipment 100 includes a part 100-a in the ECU 12 and a part 100-b in the ECU 112. The electrical equipment 110 includes a part 110-a in the ECU 12 and a part 110-b in the ECU 112.

Thus, each of the electronic control and regulating units 12, 112 comprises two independent (electrically separated) printed circuit boards, wherein only elements of the first electrical device 100 are arranged on the one circuit board and only elements of the first electrical device 110 on the other circuit board.

The ECU 12 includes the portion 100-a of the first electrical device 100 (partition A) and the portion 110-a of the second electrical device 110 (partition B).

The part 100-a of the electrical device 100 is supplied by the first electric power source 57. The part 110-a of the electronics 110 is supplied by a second electrical energy source 67.

The part 100-a of the first electrical device 100 includes, for example, the electrical and electronic components and valve coils for controlling the valves 26 and 40 (partition A). It further comprises the electrical and electronic components for controlling the electric motor 35 of the first pressure supply device 5 (partition A). For this purpose, the part 100-a of the first electrical device 100 in FIG ECU 12, the electrical and electronic components for signal processing or evaluation of the sensor 44 of the electric motor 35 of the first pressure supply device 5 (Partition A).

Preferably, the valves 26 and 40 are equipped with a single on ^{¬ control} coil, so that the valves 26 and 40 are driven only by the first electrical device 100 (partition A).

The part 100-a of the first electrical device 100 in ECU 12 further comprises the electrical and electronic components for signal processing or evaluation of the pressure sensor 19 for the first pressure-providing device 5.

The signals of the wheel speed sensors 56 are supplied to the first electrical device 100 or the part 100-a of the first electrical device 100 in the ECU 12. The first electrical device 100 or the part 100-a of the first electrical device 100 in ECU 12 receives the signal from a human-machine interface (HMI) 55, e.g. a switch to enable or disable a driving dynamics control function (ESC) or similar. fed. Depending on this, in the part 100-a of the electrical device 100, the signals of the vehicle dynamics sensor system 60 are evaluated and taken into consideration for the printing position.

The part 110-a of the second electrical device 110 in ECU 12 includes the electrical and electronic components for controlling the electric motor of the second Druckbereitstel ^¬ treatment device 2. It further includes the electrical and electronic components and valve coils for controlling the valves 23 and 32 and the Raddruckregelventile 6a-6d and 7a-7d. Conventional valves with a single drive coil are preferably used, so that the valves 6a-6d and 7a-7d (and 23, 32) can only be actuated by the second electrical device 110 (partition B).

The part 110-a of the second electrical device 110 in ECU 12 further comprises the electrical and electronic components for signal processing or evaluation of the pressure sensor 49 for the second pressure-providing device 2.

The part 110-a of the second electrical device 110 in ECU 12 further comprises electrical and electronic components for controlling the electric parking brakes (IPB) of the rear axle HA. In Fig. 1 corresponding control lines 70 are indicated.

The part 110-a of the second electrical device 110 or the second electrical device 110 is, for example, the signal of a human-machine interface 54 (HMI), e.g. a switch for actuating the electric parking brake (IPB, EPB), which is arranged on the wheels of the rear axle HA supplied.

According to the example, the signals of the second wheel speed sensors 66 are provided to the second electrical device 110 or the part 110-a.

The part 110-a of the second electrical device 110 in ECU 12 is connected to a data bus 68, e.g. a CAN bus, connected. The part 100-a of the first electrical device 100 in ECU 12 is connected to a data bus 58, e.g. a CAN bus, connected.

The first and the second data bus 58, 68 are advantageously independent of each other. As already mentioned, part of the electronics in ECU 112 belongs to the first electrical device 100, another part of the electronics in ECU 112 belongs to the second electrical device 110. Accordingly, the part 100-b of the first electrical device 100 becomes ECU 112 (Part A) supplied from the first electric power source 57 and the part 110-b of the second electrical device 110 in ECU 112 (Partition B) from the second electric power source 67th

Likewise, the portion 100-b of the first electrical device 100 in ECU 112 is connected to the data bus 58, while the portion 110-b of the second electrical device 110 in ECU 112 is connected to the data bus 68.

The parts 100-a, 100-b of the first electrical device 100 are thus connected to each other via the data bus 58, since they are spatially arranged in different ECUs 12 and 112. Accordingly, the parts 110-a, 110-b of the second electrical device 110 are connected to one another via the data bus 68.

The part 100-b of the first electrical device 100 in ECU 112 includes the electrical and electronic components as well as valve coils for driving the valves 81 and 83.

The part 100-b of the first electrical device 100 also includes the electrical and electronic components for signal processing or evaluation of the force or pressure sensor 20.

The part 100-b of the first electrical device 100 in ECU 112 is, for example, for transmitting the signals from sensor 20 directly via a signal connection line or communication line 71 to the part 100-a of the first one electrical device 100 is connected in ECU 12.

The part 110-b of the second electrical device 110 in ECU 112 includes the electrical and electronic components as well as valve coils for driving the valves 82 and 84.

The part 110-b of the second electrical device 110 also includes the electrical and electronic components for signal processing or evaluation of the displacement sensor 25.

The two units of each hydraulic unit HCU1 or 200 and electronic control unit 12 and 112 are preferably mounted on the bulkhead or the chassis, which is indicated schematically by the block 59.

In the following, exemplary methods for operating the brake system are described: a) Error-free case of the brake system

Here both partitions A and B are error free and fully functional, i. e.g. the two pressure supply devices 2, 5 and the two electrical devices 100, 110 and all valves and sensors.

A requested brake pressure is provided by means of the first pressure supply device 5 (primary pressure actuator) after opening the first isolation valve 26 by activation by means of the first electrical device 100. Thus, braking with all wheel brakes 8a-8d and optionally (jointly) controlled brake pressure is possible (4-wheel Brakes). Wheel-specific pressure controls are possible by means of the inlet and outlet valves 6a-6d, 7a-7d, which are controlled by the second electrical device 110. Based on the information of the wheel speed sensors 66

(Partition B) and the driving dynamics sensor 60 (Partition A), the pressure controls are performed with the highest precision, dynamics and control quality. b) failure in partition A, e.g. Failure of the first pressure supply device 5, the first electrical device 100 or the first energy source 57:

Since the second electrical device 110 controls the second pressure supply device 2, the overflow valve 32 and the second isolation valve 23, by activating the pressure supply device 2 and opening the second

Separating valve 23, the second pressure supply device 2 are connected to all wheel brakes 8a-8d and so built up brake pressure on all wheel brakes and by means of the spill valve 32 also (jointly) are regulated (4-wheel brakes). The first pressure supply device 5 is hydraulically separated via the normally closed isolation valve 26, which is e.g. is advantageous in the case of a leakage in the pressure supply device 5.

Wheel-individual pressure controls, in particular anti-lock control, are also possible by means of the inlet and outlet valves 6a-6d, 7a-7d, since these are actuated by the second electrical device 110 and the signals of the wheel speed sensors 66 are present to the second electrical device 110 (partition B ). Thus, the second electrical partition B or the second electrical device 110 quasi unchanged as known ABS regulations (ABS: anti-lock braking system) perform and together with the ability to build up brake pressure, all

Realize residual braking functions. c) failure in partition B, e.g. Failure of the second

Pressure supply device 2, the second electrical device 110 or the second energy source 67:

Since the first electrical device 100, the first Druckbe ^¬ riding provision device 5, the first isolation valve 26 and the Achstrennventil drives 40, by activating the

Pressure supply device 5 and opening the first

Separating valve 26, the first pressure supply device 5 are connected to all wheel brakes 8a-8d and so brake pressure to the wheel brakes 8a-8d constructed and also (jointly) are regulated (4-wheel brakes). The controllability of the axial isolating valve 40 makes it possible to set different pressures on an axle-by-axle basis. This is done e.g. after an axis-multiplexing process. For this purpose, the driving dynamics data of the sensor system 60 are used, which is assigned to the first electrical device 100 (partition A). Thus, the blocking order of the axes can be maintained and unwanted destabilization can be avoided at higher delays.

The performance of these control strategy (case c)) with respect to brake power, not on the level of the FEH ^¬ lerfreien system. However, it is sufficient for the described error case to ensure the residual braking functions. ₄

A special feature of the exemplary brake systems is the asymmetry, wherein

An electric partition B by means of eight Raddruckmodu ^¬ latorventilen (inlet valves 6a-6d and exhaust valves 7a-7d) and a pressure supply device. 2

4-wheel braking and wheel-specific pressure control even after a failure in the other electrical partition A, e.g. the first electrical device 100 or its electrical energy source 57, can perform, and

Another, independent electrical partition A by means of another pressure supply device 5 and at least one axial disconnect valve 40 (and optionally further valves) 4-wheel braking and individual axle pressure control even after a failure in the partition B, e.g. the second electrical device 110 or its electrical power source 67, can perform.

The exemplary braking systems provide the redundancy necessary for the realization of highly automated driving functions in order to implement autonomous braking requirements. Even after a serious error, such as a failure of the first power supply 57 of the partition A or the first pressure supply device 5, the brake system is able to continue to implement certain residual braking functions autonomously or controlled by an autopilot. The most important residual brake functions of the brake system are:

Build up delay;

Adhere to the blocking order of the axes and avoid unwanted destabilization at higher delays;

Steerability maintained to allow the (car) pilot also braked evasive maneuvers. The invention offers the advantage that the number of redundant components is kept as small as possible. Neither the intake and exhaust valves for wheel-individual brake pressure control nor the sensors for wheel-specific brake pressure control functions (such as anti-skid control, vehicle dynamics control etc.) are designed to be redundant.

The wheel pressure control actuators used in the system (eg valve coils of the inlet and outlet valves) and sensors are advantageously partitioned with the two redundant pressure supply devices 2, 5 by distributing the non-redundant components to the two redundant pressure supply devices 2, 5 such that in case of failure of a redundant pressure supply device, the remaining pressure supply device with the help of their associated components continue to ensure the primary functions. The failure refers to one

Pressure supply facilities on the various error possibilities such. Failure of a redundant electrical supply, a redundant arithmetic unit or a redundant hydraulic pressure provider.

Claims

Brake system for a motor vehicle with

Hydraulically actuatable wheel brakes (8a-8d) which are assigned to wheels (FL, FR) of a first vehicle axle (VA) and wheels (RL, RR) of a second vehicle axle (HA),

• an electrically operable inlet valve (6a-6d) and electrically actuated outlet valve (7a-7d) for each wheel brake ^¬ (8a-8d) for adjusting wheel-individual brake pressures ^¬,

A first electrically controllable pressure supply device (5), which is hydraulically connected separably via a first separating valve (26) to a brake supply line (13) to which the wheel brakes (8a-8d) are connected,

A second electrically controllable pressure supply device (2), which is separably hydraulically connected to the brake supply line (13) via a second separating valve (23),

wherein in the brake supply line (13) an electrically actuated axle disconnect valve (40) is arranged such that when the axial disconnect valve is closed, the Bremsver ^¬ sorgungsleitung (13) in a first and a second line section (13a, 13b) is hydraulically separated, the first line section ( 13a) with the wheel ^¬ brakes (8a, 8b) (HA) of the second vehicle axle hyd ^¬ raulisch, and the second line portion (13b) to the wheel brakes (8c, 8d) of the first vehicle axle (VA) is hydraulically connected, and wherein the second pressure-providing device (2) is hydraulically connected to the first line section (13a) via the second separating valve (23) and the first print-ready device Positioning device (5) via the first separating valve (26) to the second line section (13b) is hydraulically connected,

• a first electrical device (100) with

electrical and / or electronic elements, which activates the first pressure supply device (5),

• a second electrical device (110) with

electrical and / or electronic elements, which controls the second pressure supply device (2),

• one by means of a brake pedal (1) operable

Master brake cylinder (80) which is hydraulically connected to the brake supply line (13), and

A simulation device (3), which is operatively connected to the master brake cylinder (80),

characterized in that

the master cylinder (80) is designed as a single circuit.

Brake system according to claim 1, characterized in that the pressure chamber of the master cylinder (80) via a third separating valve (81) and a third separating valve hydraulically downstream, fourth separating valve (82) with the

Brake supply line (13) is hydraulically connected.

Brake system according to claim 1, characterized in that the pressure chamber of the master cylinder (80) via a single master cylinder isolation valve with the brake supply ^¬ line (13) is hydraulically connected, wherein the master cylinder-separating valve is designed to be double controlled.

Brake system according to one of the preceding claims, characterized in that the second Druckbereitstellungssein- direction (2) a suction port (28) which is connected to a pressurized medium reservoir (4) which is under atmospheric pressure and a pressure port (27), wherein an overflow valve (32) for adjusting or regulating the pressure provided by the second pressure supply device (2) ) is provided, via which the pressure port (27) to the suction port (28) is hydraulically connected.

Brake system according to one of the preceding claims, characterized in that the axial separation valve (40) is designed to be normally open.

Brake system according to one of the preceding claims, characterized in that the first and the second electrical device (100, 110) are electrically independent of each other, wherein the inlet and outlet valve (6a-6d, 7a-7b) of the second electrical device (110 ).

Brake system according to claim 6, characterized in that the first pressure supply device (5) is driven exclusively by the first electrical device (100) and the second Druckbereitstellungssein ^¬ direction (2) and the inlet and outlet valve (6a-6d, 7a-7d) are driven exclusively by the second electrical device (110).

Brake system according to one of the preceding claims, characterized in that the axial disconnection valve (40), in particular exclusively, by means of the first electrical device (100) is driven.

Brake system according to one of the preceding claims, characterized in that the first separating valve (26), in particular ^¬ sondere is exclusively controlled by the first electrical device (100).

10. Brake system according to one of the preceding claims, characterized in that the second separating valve (23), in particular ^¬ special exclusively, by means of the second electrical device (110) is driven.

11. Brake system according to one of the preceding claims, when dependent on claim 2, characterized in that the third separating valve (81), in particular exclusively, by means of the first electrical device (100) is driven and the fourth separating valve (82), in particular exclusively, is driven by the second electrical device (110), or vice versa.

12. Brake system according to one of the preceding claims, when appended to claim 3, characterized in that the master cylinder isolating valve by means of both the first electrical device (100) and the second electrical device (110) is driven.

13. Brake system according to one of the preceding claims, when referred back to claim 4, characterized in that the overflow valve (32), in particular exclusively, by means of the second electrical device (110) is driven.

14. Brake system according to one of the preceding claims, characterized in that the simulation means (3) connected hyd ^¬ raulisch with the master brake cylinder (80) being arranged in this connection is a parallel connection of two, in particular normally closed, Simulator release valves (83, 84), one of the simulator free gabeventile (83), in particular exclusively, by means of the first electrical device (100) is driven, while the other of the simulator release valves (84), in particular exclusively, by means of the second

electrical device (110) is driven.

Brake system according to one of claims 1 to 13, characterized in that the simulation means (3) connected hyd ^¬ raulisch with the master brake cylinder (80), wherein a single, in particular normally closed, simulator release valve is arranged in this connection, which is designed double-controllable and by means of both the first electrical device (100) and the second electrical device (110) is driven.

Brake system according to one of the preceding claims, characterized in that the master brake cylinder (80) or the simulation means (3) at least two sensors (20, 25) are supplied ^¬ arranged for detecting each of a driver's braking request size, wherein the one of the sensors (20), in particular exclusively, is connected to the first electrical device (100) and is evaluated by this, and the other of the sensors (25), in particular exclusively, connected to the second electrical device (110) and is evaluated by this.

Brake system according to one of the preceding claims, characterized in that the first electrical device (100) is supplied by a first electrical energy source (57) and the second electrical device (110) is supplied by a second electrical energy source (67), which of the first electrical energy source (57) is independent. Brake system according to one of the preceding claims, characterized in that a wheel speed sensor is provided for each of the wheel brakes (8a-8d), wherein the wheel speed sensors (66), in particular exclusively, are connected to the second electrical device (110) and are evaluated by the latter ,

19. Brake system according to one of the preceding claims, characterized in that a driving dynamics sensor (60) is seen ^¬ before, which, in particular exclusively, with the first electrical device (100) is connected and is evaluated by this.

20. Brake system according to one of the preceding claims, characterized in that a first pressure sensor (19), which is assigned to the first pressure supply device (5), and a second pressure sensor (49) which is assigned to the second pressure supply device (2) are provided , wherein the first pressure sensor, in particular exclusively, is connected to the first electrical device (100) and is evaluated by the latter and the second pressure sensor, in particular exclusively, is connected to the second electrical device (110) and is evaluated by the latter.