Electronically controlled external power braking system for a motor vehicle and brake request preselection device

Abstract

The invention relates to an electronically slip-controlled external power braking system (10), in particular for a motor vehicle, and a brake request preselection device (14). In conventional power-assisted braking systems (10), a driver initiates a braking request by applying a brake request control device (14) with a specified actuation distance. The actuation distance is detected by a sensor unit (64) and further processed by an engine control unit (16) into control signals that activate actuators which generate brake pressure and / or braking force at the assigned wheel brakes (24a; 24b; 56a; 56b). A power supply unit with several voltage sources (80a; 80b) and the use of a sensor unit (64) with at least one signal transmitter (66a; 66b) and an odd plurality of signal receivers (68a, 68b; 68c) is proposed, wherein each of the voltage sources (80a; 80b) supplies at least one of the signal receivers (68a; 68b; 68c) with electrical energy. The resulting redundancy for the power supply and for brake request detection eliminates the need for a hydraulic fallback system between the driver and the hydraulic wheel brakes (24a; 24b). The inventive power-assisted braking systems (10) are more cost-effective, have a more compact hydraulic unit (12), and can be used in autonomous vehicles.

Description

Technical background

[0001] The invention relates to an electronically controlled power brake system, in particular for a motor vehicle according to the features of the preamble of claim 1, and to a braking request specification device according to the features of the preamble of claim 11.

[0002] Power brake systems differ fundamentally from conventional vehicle braking systems in that, during normal operation of these systems, the driver is not involved in building up the brake pressure, but merely specifies a braking command. To do so, the driver applies an actuating travel to an actuating element of a braking command specification device. The latter is recorded by a sensor unit and fed to an electronic control unit for evaluation in the form of an electrical travel signal. From the travel signal, the control unit determines a control signal for a motor that drives a pressure generator. This pressure generator then, together with an electrically controllable pressure modulation device, supplies the hydraulic wheel brakes of the power brake system with pressure fluid at a brake pressure corresponding to the actuating travel and taking into account the slip conditions prevailing at the assigned wheels. State of the art

[0003] Electronically controlled power brake systems of the type described above are state-of-the-art. They feature a hydraulic unit for generating and / or regulating the brake pressure. This hydraulic unit consists of, among other things, a cuboid housing block, a pressure generator mounted thereon, a motor for driving this pressure generator, and an electronic control unit for demand-adapted electrical control of the motor. The electronic control unit is supplied with electrical power by a power supply unit.

[0004] Furthermore, known power brake systems feature a braking command input device with an actuating element that can be actuated by a driver with an actuating travel. As mentioned above, the actuating travel is detected by a sensor unit consisting of a signal transmitter and a signal receiver.

[0005] A corresponding hydraulic unit is disclosed, for example, in DE 10 2020 216 113 A1.

[0006] In this prior art, the brake command input device is integrated into the hydraulic block, which, however, is not a mandatory requirement for the present invention. Alternatively, it would also be conceivable to implement the brake command input device as a separate unit from the hydraulic unit.

[0007] The wheel brakes of the familiar power brake system are connected to the hydraulic unit via pressure lines. Pressure fluid connections between the wheel brakes and the brake command input device can be controlled using electrically controlled valves. Under normal operating conditions of the power brake system, these pressure fluid connections are interrupted; however, they are opened or released in the event of an electrical and / or mechanical malfunction. This enables the driver to build up braking pressure in the wheel brakes using muscle power by operating the brake command input device. In technical circles, this safety measure is referred to as a hydraulic fallback system.However, the valves and pressure medium connections required for this increase the construction effort, number of components, dimensions and costs of a hydraulic unit, especially if the brake request specification device cannot be integrated into the hydraulic unit due to space constraints.

[0008] Furthermore, a hydraulic fallback system still requires the presence of a driver to brake the vehicle in the event of a malfunction. Therefore, a hydraulic fallback system is hardly suitable for autonomous vehicles, where such a driver is lacking.

[0009] Furthermore, the familiar power braking system is supplied with electrical energy from a power supply with a voltage source. Even in the event of a failure of this voltage source, no external power is available, meaning that the vehicle can only be braked by the driver using muscle power. However, the achievable braking performance is correspondingly low.

[0010] Furthermore, the known power brake system includes a pedal travel simulator to provide the driver with pedal feedback under normal braking conditions of the power brake system. The pedal travel simulator is integrated into the brake circuit and receives hydraulic pressure fluid. To prevent pressure fluid displaced by the driver from flowing into the pedal travel simulator in the event of a malfunction and thus being unavailable to generate brake pressure in the wheel brakes, it is necessary to separate the simulator from the brake circuit. For this purpose, an electrically controlled simulator control valve is provided, which disadvantageously further increases the construction effort and cost of the hydraulic unit.

[0011] The object of the present invention is therefore to propose a power brake system whose functionality is reliably protected against mechanical and electrical malfunctions with reduced construction effort and lower costs and which can also be used in autonomously driven motor vehicles. Advantages

[0012] According to the invention, the proposed electronically controlled slip-controllable power brake system is equipped with a voltage supply unit which comprises at least two mutually independent voltage sources and which further comprises a sensor unit with an odd plurality, preferably 3, signal receivers, wherein the voltage sources of the voltage supply unit each supply at least one signal receiver with electrical energy.

[0013] Based on these features, a power braking system is provided that, due to its redundancy in power supply and braking command detection, does not require a hydraulic fallback system. The proposed power braking system therefore features wheel brakes that are hydraulically decoupled from the driver, thus eliminating the need for controllable hydraulic components, features a compact and cost-effective hydraulic unit, and allows for high flexibility in its installation in a motor vehicle body. Furthermore, a power braking system according to the invention is suitable for use in autonomously driven motor vehicles.

[0014] Further advantages or advantageous developments of the invention emerge from the subclaims or from the following description.

[0015] A further development of the invention relates to the braking command input device or its arrangement. This braking command input device can be integrated into the hydraulic unit, thus creating a compact unit that can be installed into the body of a motor vehicle with little effort, or it can alternatively be designed separately, i.e., separately from the hydraulic unit. A design separate from the hydraulic unit eliminates the need to arrange the hydraulic unit on the bulkhead of the body, i.e., the wall that separates the engine compartment from the passenger compartment of the motor vehicle, and thus allows better utilization of the limited installation space available in a vehicle body. Arranging the hydraulic unit away from the bulkhead may improve the braking performance.The crash behavior of a vehicle body and the vehicle occupants can be better protected from potential injuries caused by a hydraulic unit penetrating the passenger compartment in the event of an accident, supposedly due to body deformation. Furthermore, the installation position for the hydraulic unit can be selected independently of the position of the vehicle's steering unit, which consequently simplifies the assembly of various body variants at the vehicle manufacturer.

[0016] The proposed power brake system can be implemented as a hydraulic brake system with hydraulically actuated wheel brakes on the vehicle's axles or as a so-called hybrid brake system with hydraulic wheel brakes on a first axle and electromechanically actuated wheel brakes on a second axle. Different brake designs on the wheel brakes of a vehicle axle further increase the reliability of the power brake system.In the hybrid braking system design, the wheel brake control units of the electromechanical wheel brakes, along with one of the signal receivers, are supplied with power from one of the voltage sources, while the second voltage source supplies the unit control unit and the remaining signal receivers and is thus responsible for building up brake pressure in the hydraulic wheel brakes. This allows the brake request signals received by the signal receivers to be mutually validated. Furthermore, it ensures that even in the event of a malfunction in one of the voltage sources or a mechanical defect in the hydraulic unit, its components, or the hydraulic wheel brakes, the wheel brakes on the other axle remain available, allowing the vehicle to continue to brake safely.Braking power continues to be generated by external power, ensuring high deceleration even in the event of a malfunction. Any loss of comfort or irritation to vehicle occupants is largely avoided. drawing

[0017] Embodiments of the invention are illustrated in the drawings and explained in detail in the following description. The drawing comprises a total of six figures, in which corresponding components are provided with identical reference numerals.

[0018] Shown in: • Fig. 1 shows a first embodiment of an external power brake system according to the invention with a braking request detection device separated from the hydraulic unit, based on a schematically simplified overview representation; • Fig. 2 shows a second exemplary embodiment of an external power brake system according to the invention with a braking request detection device integrated into a hydraulic unit, also based on a schematically simplified overview representation; • Fig. 3 a braking request detection device with 2 signal transmitters and 3 signal receivers based on a cross-section along the section line XX according to Fig. 4 by a hydraulic unit with integrated braking request detection device; • Fig. 4 the braking request detection device according to Fig. 3 based on a longitudinal section through the hydraulic unit; • Fig. 5 a braking request detection device with 1 signal transmitter and 3 signal receivers based on a cross section along the section line YY according to Fig. 6 by a hydraulic unit with integrated braking request detection device; • Fig. 6 the braking request detection device according to Fig. 5 using a longitudinal section through the hydraulic unit. Description of the embodiments

[0019] Fig. Figure 1 shows a first embodiment of a power brake system (10) according to the invention, comprising a braking command input device (14) configured separately from a hydraulic unit (12). Separated in this context means that this braking command detection device (14) forms an assembly that can be installed separately from the hydraulic unit (12) in the body of a motor vehicle and is electrically connected to the hydraulic unit (12) or a unit control unit (16) of this hydraulic unit (12).

[0020] The figure shows an outline of the hydraulic unit (12). It comprises several electrically controllable components, including a brake pressure generator (20) driven by a motor (18) for supplying pressure medium to a brake circuit (22) with a total of two hydraulic wheel brakes (24a; 24b) connected to the hydraulic unit (12). A plunger piston (26) serves as the brake pressure generator (20). The plunger piston (26) is movably guided in a plunger cylinder (28) and can be driven by the motor (18) to perform an axial movement. The plunger piston (26) defines a working chamber (30) in the plunger cylinder (28) that is filled with pressure medium and whose volume decreases when the plunger piston (26) moves in the direction of pressure build-up. Conversely, pressure medium flows back into this working chamber (30) when the plunger piston (26) is driven backwards, ie in the pressure reduction direction, and the volume of the working chamber (30) consequently increases.

[0021] For wheel-individual control of the provided brake pressure, a pressure modulation device (32) comprising one electrically controllable inlet valve (34a; 34b) and one electrically controllable outlet valve (36a, 36b) per wheel brake (24a; 24b) is provided downstream of the brake pressure generator (20). The inlet valves (34a; 34b) are electrically controllable, normally open 2 / 2-way valves, while the outlet valves (36a; 36b) are designed as electrically switchable, normally closed 2 / 2-way valves.

[0022] The inlet valves (34a; 34b) are connected in parallel to one another to a pressure line (38) coming from the brake pressure generator (20). This pressure line (38) can be controlled by means of an electrically controllable, normally closed shut-off valve (40) which is arranged between the brake pressure generator (20) and the inlet valves (34a, 34b) in the brake circuit (22). Since, in the event of a necessary brake pressure reduction during a braking operation with slip control, pressure medium is released from the brake circuit (22) via the outlet valves (36a; 36b) into a reservoir (42) and is consequently no longer available for future brake pressure build-up, the pressure medium volume of the working chamber (30) decreases continuously during the operation of the power brake system (10) and must be replenished as soon as this working chamber (30) has reached a minimum volume or the plunger piston (26) has reached a defined outer reversal point.For this purpose, the connection between the brake pressure generator (20) and the hydraulic wheel brakes (24) is briefly interrupted by the shut-off valve (40), and the plunger piston (26) is actuated in parallel in the pressure reduction direction. The negative pressure that develops in the expanding working chamber (30) causes pressure medium to flow from the reservoir (42) into the working chamber (30) via an intake line (44). This intake line (44) is controlled by a loading valve (46). This loading valve (46) is a hydraulically actuated, spring-loaded seat valve that opens in the direction from the reservoir (42) to the working chamber (30) of the brake pressure generator (20) and closes off the opposite direction. A pressure sensor (48) is in contact with the intake line (44), which detects the pressure level prevailing in the working chamber (30) and sends a corresponding electrical pressure signal to the unit control unit (16).This aggregate control unit (16) is preferably mounted externally on a housing block (84; . Fig. 3) of the hydraulic unit (12) and controls or regulates the brake pressure in the brake circuit (22) by means of an electrical control of the mentioned components adapted to the braking request.

[0023] The outlet valves (36a; 36b) are directly connected to the reservoir (42) via a common return line (50). The latter is also mounted on the outside of the housing block (84, Fig. 3) of the hydraulic unit (12) and coupled thereto in a pressure-medium-conducting manner. The interior of the reservoir (42) is divided into two interconnected pressure-medium chambers (52a, 52b), with the return line (50) opening into the first pressure-medium chamber (52a), while the intake line (44) is connected to the second pressure-medium chamber (52b).

[0024] Furthermore, a rotation angle sensor (54) is provided on the hydraulic unit (12) in order to detect an angle of rotation generated by a rotor (98; Fig. 3) of the motor (18) and the rotational position of this rotor (98).

[0025] The two hydraulic wheel brakes (24a; 24b) of the power brake system (10) are arranged jointly on a first axle, preferably the front axle (VA), of a motor vehicle. A second axle, preferably the rear axle (RA), of this motor vehicle, in contrast, is equipped with electromechanical wheel brakes (56a; 56b). These each have an actuator controlled by an associated wheel brake control unit (58a; 58b). In accordance with the control signal, the actuator mechanically applies the wheel brake (56a; 56b), thus generating a desired braking effect.

[0026] To specify a braking request, the power brake system (10) is equipped with a braking request specification device (14). This braking request specification device (14) forms a structural unit that is installed spatially separate from the hydraulic unit (12) in the vehicle body and is electrically connected to this hydraulic unit (12) or its unit control unit (16). The braking request specification device (14) has an actuating element (62), for example a pedal or a lever, which can be acted upon by the driver of the motor vehicle with an actuating travel representing the braking request. This actuating travel is detected by a sensor unit (64) and transmitted to the unit control unit (16). According to the invention, the sensor unit (64) for this purpose comprises at least one signal transmitter (66a; 66b; Fig. 4) and an odd number of signal receivers (68a; 68b; 68c). In the embodiment according to Fig. 1, for example, 3 signal receivers (68a, 68b; 68c) are used, which interact with two signal transmitters (66a; 66b; Fig. 4) independently transmit travel signals to the unit control unit (16). The incoming signals are checked against each other for plausibility, allowing a faulty signal from a signal receiver (68a; 68b; 68c) to be detected and, if necessary, taken into account.

[0027] To simulate an actuation travel and an adapted reaction of the actuating element (62) on the driver, the braking command input device (58) also has a travel simulator (70). This travel simulator (70) consists of a simulator piston (72) that is accommodated in a simulator cylinder (74) and displaceably guided therein against the force of an elastic return device (76). The simulator piston (72) is coupled to the actuating element (62) of the braking command input device (60). One or more springs and / or elastomer components, optionally also in combination with one another, can be used as the return device (76).

[0028] To ensure the power supply of the power brake system (10), a power supply unit with two independent power sources (80a; 80b) is provided. A first power source (80a) supplies electrical power to two of the three signal receivers (68a; 68b) and the unit control unit (16) of the hydraulic unit (12), while the second power source (80b) serves to supply electrical power to the two wheel brake control units (58a; 58b) of the electromechanical wheel brakes (56a; 56b) and the third signal receiver (68c).

[0029] The signals from the signal receivers (68a; 68b; 68c) are fed to the assembly control unit (16) and the wheel brake control units (58), respectively. Signal lines (82) are also provided between the wheel brake control units (58) and the assembly control unit (16).

[0030] In summary, in the power brake system (10) designed according to the invention, the power supply for the devices generating the braking torque and the braking request detection are designed redundantly. The signal receivers (68) required for braking request detection are also provided redundantly, and finally, wheel brakes (24a, 24b; 56a; 56b) of different designs (hydraulic; electromechanical) are used on the various axles of the vehicle. In summary, this creates a power brake system (10) with particularly high reliability against electrical, mechanical or hydraulic malfunctions, which in particular does not require a conventional hydraulic fallback level, i.e., without a controllable pressure medium connection between the braking request input device (14) and the hydraulic wheel brakes (24a; 24b). Furthermore, a hydraulic travel simulator and its separability from the brake circuit can be dispensed with.Advantageously, this results in less construction effort for the hydraulic unit (12) and for the power brake system (10) and also saves costs and installation space.

[0031] The same applies to a Fig. 2 shows a second embodiment of the invention, which differs from the embodiment according to Fig. 1 in that the braking request specification device (14) is integrated into the hydraulic unit (12) for controlling and regulating the hydraulic brake pressure, thus not forming a separate structural unit from this hydraulic unit (12). Integrated in this context is to be understood as meaning that the travel simulator (70), the signal transmitter(s) (66a; 66b; Fig. 4) and the odd plurality of signal receivers (68a; 68b; 68c) on or in the housing block (84; Fig. 3) of this hydraulic unit (12). The actuating element (62) coupled to the simulator piston (72) of the travel simulator (70) is located opposite one of the outer sides of the housing block (84; Fig. 4) and thus enables operation by the driver. However, this embodiment requires the hydraulic unit (12) to be mounted on a bulkhead (S; Fig. 4) the body of a motor vehicle, which has an engine compartment (M; Fig. 4) from a passenger compartment (F; Fig. 4) separates.

[0032] Fig. 3 presents a cross-section along the section line XX according to Fig. 4 by a hydraulic unit (12) with integrated brake request device (14) according to Fig. 2 and uses this cross-section to illustrate the arrangement of the components.

[0033] The hydraulic unit (12) comprises the centrally arranged, cuboid-shaped housing block (84), on the Fig. 3 The engine control unit (16) is mounted on the right side of the block. The right side of the block is therefore referred to as the control unit side. A housing extension (86) can be seen on the side of the block opposite the engine control unit (16).

[0034] The side facing the observer, referred to as the flange side of the housing block (84), has in the region of its upper third a circular simulator receptacle (88), the interior of which is used to accommodate the travel simulator (70; Fig. 1) or the simulator piston (72; Fig. 1) and its reset device (76; Fig. 1) and thus forms the simulator cylinder (74). The simulator receptacle (88) ends in the form of a blind hole inside the housing block (84), with a bottom of the blind hole serving as the first support for the elastic return device (76) (see Fig. 4). On a side of the simulator receptacle (88) facing the housing extension (86), two circular signal transmitter receptacles (90a; 90b) are visible, offset upwards and downwards relative to the horizontal axis of the simulator receptacle (88). Signal receivers (68a; 68b; 68c) are arranged above, below, and between the two signal transmitter receptacles (90a; 90b) and each extend transversely to the direction of extension of the signal transmitter receptacles (90a; 90b). The signal receivers (68a; 68b) arranged above and below extend in the direction of the assembly control unit (16) and are directly connected to the control unit electronics and the first voltage source (80a) for power supply and signal transmission. The signal receiver (68c) arranged between the signal transmitter receptacles (90) extends in the opposite direction in the direction of the housing extension (86) and is connected there to the second voltage source (80b).

[0035] The signal receivers (68a; 68b; 68c) used are each pin-shaped and carry one or more magnetic field-sensitive detection electronics (94) at their ends near the signal generator receptacles (90).

[0036] Finally, the Fig. 3 shows another exemplary arrangement of the motor (18) for driving the brake pressure generator (20). The motor is located below the braking command input device (14) on the hydraulic unit (12) and comprises a rotor (98) fixedly arranged on a drive shaft (96). The rotor (98) and drive shaft (96) are rotatably accommodated inside the unit control unit (16), with an end of the drive shaft (96) facing away from the rotor (98) projecting into the housing block (84) of the hydraulic unit (12) and driving the brake pressure generator (not shown) located there, preferably via an intermediate gear (not shown). Due to its location in the unit control unit (16), the motor (18) can be contacted easily and in a space-saving manner, does not require an external motor housing, and is supplied with electrical energy by the associated first voltage source (80a).

[0037] As mentioned, a rotation angle or a rotation position of the rotor (98) is detected by means of the rotation angle sensor (54; Fig. 1). This comprises an angle signal transmitter (100) arranged at the free end of the drive shaft (96) and angle detection electronics (102) housed in the housing extension (86) on the side of the hydraulic unit (12) opposite the unit control unit (16). A contact tongue (104) penetrating the housing block (84) ensures a possible signal exchange between the angle detection electronics (102) and the electronics of the unit control unit (16).

[0038] Fig. Figure 4 shows the hydraulic unit (12) described above in longitudinal section. Among other things, the travel simulator (70) arranged in the simulator receptacle (88) or the simulator cylinder (74) can be seen, with the simulator piston (72) and the return device (76) that returns this simulator piston (72). The latter is symbolically represented as a return spring. The simulator piston (72) is connected at a piston head to the actuating element (62), a pedal in the illustrated embodiment. Also firmly connected to the simulator piston (72) are two signal transmitters (66a; 66b) that are movably received in the two signal transmitter receptacles (90a; 90b) provided to the sides of the simulator receptacle (88). These signal transmitters (66a; 66b) are each pin-shaped, extend axially parallel and at a radial distance from a longitudinal axis of the simulator piston (72) and are equipped at their free ends with a transmitter element (106a; 106b) having a magnetic field.The signal transmitters (66a; 66b) follow an axial movement of the simulator piston (72) and thus move relative to the stationary signal receivers (68a; 68b; 68c). In this case, the magnetic field-generating transmitter elements (106a; 106b) are released in their associated signal receivers (68a; 68b; 68c; . Fig. 3) each outputs a travel signal dependent on the travel of the simulator piston (72).

[0039] A basic position of the simulator piston (72) is predetermined by a cup-shaped stop sleeve (108). This stop sleeve (108) is fastened to the flange side of the hydraulic unit (12) and is thus arranged, at least in section, between the housing block (84) of the hydraulic unit (12) and the firewall S of the vehicle. In its non-actuated state, the simulator piston (72) is pressed by the return device (76) or return spring with its piston head against the inside of a sleeve base of this stop sleeve (108) until it stops. An opening is provided on the sleeve base through which the actuating element (62), which projects into the passenger compartment F of the vehicle, is coupled to the simulator piston (72).

[0040] In Fig. 5 shows a hydraulic unit (12) in cross section, which extends from the hydraulic unit to Fig. 3 in the design of the braking request setting device (14). The hydraulic unit (12) according to Fig. 5 dispenses with signal transmitters in associated signal transmitter receptacles and has three signal receivers (68a; 68b; 68c) arranged successively along the circumference of the simulator receptacle (88) on an imaginary vertical axis and an imaginary horizontal axis through the center of this simulator receptacle (88). In this example, two signal receivers (68a; 68b) are also connected to the unit control unit (16) and the first voltage source (80a), respectively, while the third signal receiver (68c) is connected to the second voltage source (80b) inside the housing extension (86).

[0041] Fig. 6 shows, comparable to the representation in Fig. 4, the embodiment according to Fig. 5 in longitudinal section. However, in this example, the function of the signal transmitter is performed by the simulator piston (72) in that it carries a signal transmitter (66) or an element having a magnetic field at its end facing away from the actuating element (62). This element having a magnetic field extends a sleeve-shaped section of the simulator piston (72), into which a piston-side end of the elastic return device (76) protrudes in sections. The element having a magnetic field is firmly connected to the simulator piston (72) and follows its actuating path. Its end protruding into the interior of the simulator receptacle (88) also acts as a stop for the simulator piston (72) at the base of the simulator receptacle (88), thus limiting the maximum possible piston stroke and preventing possible damage to the return device (76) due to undesired blocking.

[0042] Of course, changes or additions to the described embodiments are conceivable, which do not depart from the scope of protection specified by the following claims.

[0043] In this context, it should be noted that the embodiments according to the Fig. 1 and Fig. 2 each disclose a hydraulic brake circuit (22), the pressure line (38) of which between the brake pressure generator (20) and the pressure modulation device (32) can be shut off by precisely one shut-off valve (40). Downstream of this shut-off valve (40), the pressure line (38) branches into two pressure line branches (38a; 38b), each serving one of the hydraulic wheel brakes (24a; 24b). When the shut-off valve (40) closes, only a pressure reduction is possible, but no pressure build-up is possible in these hydraulic wheel brakes (24a; 24b).

[0044] Instead of a single shut-off valve (40), each pressure line branch (38a; 38b) could alternatively be equipped with an associated shut-off valve (40), thus comprising two shut-off valves in total. Should a leak occur in a line section between one of the shut-off valves (40) and an associated hydraulic wheel brake (24), two shut-off valves (40) offer the possibility of hydraulically decoupling the leaking pressure line branch (38a or 38b) by closing the associated shut-off valve (40) and continuing to pressurize the non-leaking pressure line branch (38b or 38a) with pressure fluid under braking pressure through the still-open shut-off valve. Thus, even in the event of a leak, at least one of the hydraulic wheel brakes (24a; 24b) would still be available to build up a braking effect, would support the electromechanical wheel brakes (56a; 56b) and thus increase the reliability of the power brake system (10). QUOTES CONTAINED IN THE DESCRIPTION

[0000] This list of documents submitted by the applicant was generated automatically and is included solely for the convenience of the reader. This list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions. Cited patent literature

[0000] DE 10 2020 216 113 A1

[0005]

Claims

[1] Electronically controlled power brake system (10), in particular for a motor vehicle, with a braking request specification device (14) which, for specifying a braking request, has an actuating element (62) which can be actuated to an actuating path and, for detecting this actuating path, a sensor unit (64) with a signal transmitter (66) and a signal receiver (68); with at least one brake circuit (22) for supplying hydraulic wheel brakes (24a; 24b) with a pressure medium under brake pressure; with a hydraulic unit (12) which has a brake pressure generator (20) driven by a motor (18) and an aggregate control unit (16) for controlling and regulating the brake pressure and with a voltage supply unit for supplying the power brake system (10) with electrical energy, characterized by , that the voltage supply unit comprises at least two mutually independent voltage sources (80a; 80b) and that the sensor unit (64) has an odd plurality, preferably 3, signal receivers (68a; 68b; 68c), wherein the voltage sources (80a; 80b) each supply at least one signal receiver (68a; 68b, 68c) with electrical energy. [2] Power brake system according to claim 1, characterized by that the braking request setting device (14) is integrated into the hydraulic unit (12) or forms an assembly separate from the hydraulic unit (12). [3] Power brake system according to claim 1, characterized by that the sensor unit (64) has at least two signal transmitters (66a; 66b). [4] Power brake system according to one of claims 1 to 3, characterized byin that the braking request specification device (14) comprises a travel simulator (70) with a simulator piston (72) which can be acted upon by the actuating element (62) and which is displaceably guided inside a simulator cylinder (74) against the force of an elastic return device (76). [5] Power brake system according to one of claims 1 to 4, characterized by that the at least one signal generator (66a; 66b) is formed separately from the simulator piston (72) and is coupled to the simulator piston (72) in such a way that the signal generator (66a; 66b) follows a movement of this simulator piston (72). [6] Power brake system according to one of claims 1 to 5, characterized by that the at least one signal generator (66a; 66b) is attached directly to the simulator piston (72). [7] Power brake system according to one of the preceding claims, characterized bythat the hydraulic wheel brakes (24a; 24b) are assigned to a first axle (VA) of the motor vehicle, while a second axle (HA) of the motor vehicle is equipped with electromechanically actuated wheel brakes (56). [8] Power brake system according to claim 7, characterized by , that the hydraulic wheel brakes (24a; 24b) are supplied with pressure medium via a common brake circuit (22), wherein the brake circuit (22) has a pressure line (38) with two mutually parallel pressure line branches (38a; 38b) for supplying a wheel brake (24a; 24b) with brake fluid under brake pressure, and wherein at least one shut-off valve (40) which can be electrically controlled by the unit control unit (16) is provided in order to interrupt the supply of the wheel brakes (24a; 24b) with pressure medium as required. [9] Power brake system according to claim 7, characterized bythat the unit control unit (16), a first signal receiver (68a) and a second signal receiver (68b) are assigned to a first voltage source (80a), while a third signal receiver (68c) and the wheel brake control units (58a; 58b) of the electromechanical wheel brakes (56) are assigned to a second voltage source (80b). [10] Power brake system according to claim 8, characterized by that the first signal receiver (68a) and the second signal receiver (68b) are directly contacted with the unit control unit (16). [11] Brake request specification device for specifying a braking request, comprising an actuating element (62) which can be actuated to an actuating path and a sensor unit (64) with a signal transmitter (66) and a signal receiver (68), characterized by that the braking request specification device (14) is designed according to the characterizing features of one of claims 1 to 6.

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