BRAKING SYSTEM FOR A VEHICLE

Abstract

The disclosure relates to a braking system for a vehicle having at least four brakable wheels. The braking system comprises at least four brake actuator units, each of which can be associated with one of the wheels of the vehicle, as well as a first electronic control unit and a second electronic control unit. Each brake actuator unit has its own signal line via which the relevant brake actuator unit is connected in terms of signaling to the first control unit and the second control unit, so that each of the brake actuator units can be actuated both by the first control unit and by the second control unit.

Claims

1. A Braking system for a vehicle having at least four brakable wheels, comprising at least four brake actuator units, each of which can be associated with one of the wheels of the vehicle, a first electronic control unit, and a second electronic control unit, wherein each brake actuator unit has its own signal line via which a corresponding brake actuator units from the at least four brake actuator units is connected in terms of signaling to the first control unit and the second control unit, so that each of the brake actuator units can be actuated both by the operation of the first control unit and the second control unit.

2. The braking system according to claim 1, further comprising a first power supply unit and a second power supply unit, the power supply units being independent of one another.

3. The braking system according to claim 2, wherein a first subset of the brake actuator units is coupled to the first power supply unit for the supply of power and a second subset of the brake actuator units is coupled to the second power supply unit for the supply of power.

4. The braking system according to claim 2, wherein each of the brake actuator units can optionally be coupled to the first power supply unit and to the second power supply unit for the supply of power.

5. The braking system according to claim 2, wherein the first control unit and/or the second control unit can optionally be coupled to the first power supply unit and to the second power supply unit for the supply of power.

6. The braking system according to claim 2, wherein: the first control unit is coupled to a first power supply switch for the supply of power, the first power supply switch connecting the first control unit to the first power supply unit in a first switching position and connecting the first control unit to the second power supply unit in a second switching position and/or the second control unit is coupled to a second power supply switch for the supply of power, the second power supply switch connecting the second control unit to the first power supply unit in a first switching position and connecting the second control unit to the second power supply unit in a second switching position and each of the brake actuator units is coupled to a first power supply switch or a second power supply switch for the supply of power, the first power switch connecting the relevant brake actuator unit to the first power supply unit in a first switching position and connecting the relevant brake actuator unit to the second power supply unit in a second switching position, and the second power supply switch connecting the relevant brake actuator unit to the first power supply unit in a first switching position and connecting the relevant brake actuator unit to the second power supply unit in a second switching position.

7. The braking system according to claim 1, wherein each of the brake actuator units comprises an electromechanical brake actuator.

8. The braking system according to claim 2, wherein a brake actuation unit is provided which is coupled in terms of signaling to both the first control unit and the second control unit, with the brake actuation unit comprising a brake pedal.

9. The braking system according to claim 1, wherein the first control unit and the second control unit are coupled to the signal lines of the brake actuator units via at least one gateway.

10. The braking system according to claim 1, wherein the first control unit and the second control unit are arranged adjacent to or at a distance from one another.

11. The braking system according to any of the claim 1, wherein at least one of the signal lines is a bus line.

12. The braking system according to claim 1, wherein the first control unit and/or the second control unit can be or is coupled in terms of signaling to a steering actuator unit, so that the steering actuator unit can be actuated by the first control unit and/or by the second control unit.

13. The braking system according to claim 12, wherein the steering actuator unit is a steering drive unit that can be associated with a front axle.

14. The braking system according to claim 12 wherein a steering actuation unit is coupled in terms of signaling both to the first control unit and the second control unit.

15. The braking system according to claim 1, wherein at least one driving state sensor is coupled in terms of signaling both to the first control unit and to the second control unit.

16. The braking system of claim 3, wherein the first subset and the second subset are free of intersections.

17. The braking system of claim 2, wherein: the first control unit is coupled to a first power supply switch for the supply of power, the first power supply switch connecting the first control unit to the first power supply unit in a first switching position and connecting the first control unit to the second power supply unit in a second switching position and the second control unit is coupled to a second power supply switch for the supply of power, the second power supply switch connecting the second control unit to the first power supply unit in a first switching position and connecting the second control unit to the second power supply unit in a second switching position or each of the brake actuator units is coupled to a first power supply switch or a second power supply switch for the supply of power, the first power switch connecting the relevant brake actuator unit to the first power supply unit in a first switching position and connecting the relevant brake actuator unit to the second power supply unit in a second switching position, and the second power supply switch connecting the relevant brake actuator unit to the first power supply unit in a first switching position and connecting the relevant brake actuator unit to the second power supply unit in a second switching position.

18. The braking system of claim 12, wherein the steering actuator unit is a steering drive unit that can be associated with a feedback unit that can be associated with a steering wheel.

19. The braking system according to claim 18 wherein a steering actuation unit is coupled in terms of signaling both to the first control unit and the second control unit, wherein the steering actuation unit comprises a steering wheel.

20. The braking system according to claim 12, wherein at least one driving state sensor is coupled in terms of signaling both to the first control unit and to the second control unit.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0033] The disclosure is explained below with reference to various exemplary arrangements which are shown in the accompanying drawings, in which:

[0034] FIG. 1 shows a braking system according to the disclosure in a schematic circuit diagram,

[0035] FIG. 2 is a simplified view of a variant of the braking system from FIG. 1 and

[0036] FIG. 3 shows a further variant of the braking system according to the disclosure, which is specially designed for use in autonomously or partially autonomously operated vehicles.

DETAILED DESCRIPTION

[0037] FIG. 1 shows a braking system 10 for a vehicle having a total of four brakable wheels.

[0038] The braking system 10 therefore comprises a total of four brake actuator units 12a, 12b, 12c, 12d, each of which is associated with one of the wheels of the vehicle (not shown in detail).

[0039] The brake actuator unit 12a is associated with a front-left wheel. The brake actuator unit 12b is associated with a front-right wheel. The brake actuator unit 12c is associated with a rear-left wheel and the brake actuator unit 12d is associated with a rear-right wheel.

[0040] In one exemplary arrangement, the brake actuator units 12a, 12b, 12c, 12d are constructed identically.

[0041] Each of the brake actuator units 12a, 12b, 12c, 12d comprises an electromechanical brake actuator 14a, 14b, 14c, 14d, which comprises an electric motor (not shown in detail) having a spindle drive.

[0042] By actuating the electric motor, a brake pad coupled to the spindle drive can thus be applied to an associated brake disk 16a, 16b, 16c, 16d, thus producing a braking effect.

[0043] Furthermore, each of the brake actuator units 12a, 12b, 12c, 12d is equipped with its own controller 18a, 18b, 18c, 18d, which is used to control the respectively associated electromechanical brake actuator 14a, 14b, 14c, 14d.

[0044] In addition, each of the brake actuator units 12a, 12b, 12c, 12d has a position sensor 20a, 20b, 20c, 20d by which, for example, a position of the electromechanical brake actuator 14a, 14b, 14c, 14d can be detected.

[0045] Furthermore, a rotational speed sensor 22a, 22b, 22c, 22d is provided in each of the brake actuator units 12a, 12b, 12c, 12d, by which a rotational speed of the wheel associated with the relevant brake actuator unit 12a, 12b, 12c, 12d can be detected.

[0046] The position sensors 20a, 20b, 20c, 20d and the rotational speed sensors 22a, 22b, 22c, 22d are each connected in terms of signaling to their associated controllers 18a, 18b, 18c, 18d.

[0047] The braking system 10 also has a first electronic control unit 24 and a second electronic control unit 26.

[0048] In the exemplary arrangement shown, the first electronic control unit 24 and the second electronic control unit 26 are positioned at a certain distance from one another on the vehicle. More precisely, the control unit 24 is arranged in a front region of the vehicle and the control unit 26 is arranged in a rear region, but this is not intended to be limiting.

[0049] Furthermore, a first gateway 28 is provided adjacent to the first control unit 24 and a second gateway 30 is provided adjacent to the second control unit 26.

[0050] The controller 18a is coupled to the first gateway 28 via a signal line 32. The first gateway 28 is in turn connected in terms of signaling to the first control unit 24. In addition, a signal line 34 extends from the first gateway 28 to the second control unit 26.

[0051] The controller 18a and thus the brake actuator unit 12a are thus connected in terms of signaling via separate signal lines 32, 34 to both the first control unit 24 and the second control unit 26.

[0052] The brake actuator unit 12a can therefore be actuated by the first control unit 24 and by the second control unit 26.

[0053] The controller 18b is coupled via a signal line 36 to the first gateway 28, which in turn is connected to the first control unit 24.

[0054] In addition, the first gateway 28 is connected in terms of signaling to the second control unit 26 via a signal line 38.

[0055] The controller 18b and thus the brake actuator unit 12b are therefore also connected in terms of signaling via separate signal lines 36, 38 both to the first control unit 24 and to the second control unit 26.

[0056] The brake actuator unit 12b can thus be actuated by the first control unit 24 and by the second control unit 26.

[0057] The same applies to the brake actuator units 12c and 12d on the rear axle.

[0058] The controller 18c is connected to the second gateway 30 via a signal line 40. The second gateway 30 is in turn coupled to the second control unit 26. In addition, the second gateway 30 is connected in terms of signaling to the first control unit 24 via a signal line 42.

[0059] As a result, the controller 18c and thus the brake actuator unit 12c are connected in terms of signaling via separate signal lines 40, 42 both to the first control unit 24 and to the second control unit 26.

[0060] For this reason, the brake actuator unit 12c can be actuated by the first control unit 24 and by the second control unit 26.

[0061] Furthermore, the controller 18d is connected to the second gateway 30 via a signal line 44. As already explained, the second gateway 30 is connected to the second control unit 26.

[0062] In addition, the second gateway 30 is connected to the first control unit 24 via a signal line 46.

[0063] Thus, the controller 18d and thus the brake actuator unit 12d are also connected in terms of signaling via separate signal lines 44, 46 both to the first control unit 24 and to the second control unit 26.

[0064] The brake actuator unit 12d can thus be actuated by the first control unit 24 and by the second control unit 26.

[0065] The braking system 10 further comprises a brake actuation unit 48.

[0066] The brake actuation unit 48 has a brake pedal 50 which can be actuated by a driver of the vehicle and which interacts with a simulator unit 52. The simulator unit 52 is used to generate a restoring force on the brake pedal 50.

[0067] In addition, a total of two pedal displacement sensors 54, 56 and a total of two pedal force sensors 58, 60 are provided within the brake actuation unit 48.

[0068] The pedal displacement sensors 54, 56 are designed to each detect an actuation displacement of the brake pedal 50.

[0069] The pedal force sensors 58, 60 permit an actuation force on the brake pedal 50 to be detected in each case.

[0070] The brake actuation unit 48 is connected in terms of signaling to the first control unit 24 via a signal line 62 and to the second control unit 26 via a signal line 64.

[0071] A signal generated by the brake actuation unit 48, which represents a drivers request, can therefore be taken into account in both the first control unit 24 and the second control unit 26.

[0072] The braking system 10 also comprises a parking brake switch 66 which is coupled to the first control unit 24 via a signal line 68 and to the second control unit 26 via a signal line 70.

[0073] The first control unit 24 can also be coupled to further control devices of the vehicle via a signal line 72. In particular, sensor values relating to the driving state are communicated to the first control unit 24 via the signal line 72. These relate e.g., to characteristic values of the driving dynamics such as a yaw rate.

[0074] In the same way, the second control unit 26 can be coupled to further control devices of the vehicle via a signal line 74. In particular, sensor values relating to the driving state are communicated to the second control unit 26 via the signal line 74, and these values can be the same as those already mentioned in connection with the first control unit 24.

[0075] Two mutually independent power supply units are provided for supplying power to the braking system 10.

[0076] A supply of power by a first power supply unit 76 is symbolized by dash-dotted arrows.

[0077] A supply of power by a second power supply unit 78 is symbolized by means of dashed arrows.

[0078] In the exemplary arrangement according to FIG. 1, a first power supply switch 80 and a second power supply switch 82 are also provided.

[0079] Both power supply switches 80, 82 are connected on the input side to both the first power supply unit 76 and to the second power supply unit 78.

[0080] On the output side, the first control unit 24, the first gateway 28, the brake actuator unit 12a and the brake actuator unit 12b are connected to the first power supply switch 80.

[0081] The first power supply switch 80 connects the first control unit 24, the first gateway 28 and the brake actuator units 12a, 12b to the first power supply unit 76 in a first switching position and to the second power supply unit 78 in a second switching position.

[0082] The second control unit 26, the second gateway 30, the brake actuator unit 12c and the brake actuator unit 12d are connected on the output side to the second power supply switch 82.

[0083] The second power supply switch 82 connects the second control unit 26, the second gateway 30 and the brake actuator units 12c, 12d to the first power supply unit 76 in a first switching position and to the second power supply unit 78 in a second switching position.

[0084] The brake actuation unit 48 is coupled both to the first power supply unit 76 and to the second power supply unit 78.

[0085] In the exemplary arrangement shown, the first control unit 24 is not only designed to actuate the brake actuator units 12a, 12b, 12c, 12d, but is also coupled to a steering actuator unit 86 via a signal line 84.

[0086] The second control unit 26 is also coupled to the steering actuator unit 86 via a signal line 88.

[0087] The steering actuator unit 86 can thus be actuated by the first control unit 24 and/or by the second control unit 26.

[0088] In the exemplary arrangement shown, the steering actuator unit 86 is a steering drive unit that can be associated with a front axle.

[0089] Alternatively, the steering actuator unit 86 is a feedback unit that can be associated with a steering wheel.

[0090] The first control unit 24 is also coupled via a signal line 90 to a steering actuation unit 92, which comprises a steering wheel 93.

[0091] The steering actuation unit 92 is likewise coupled to the second control unit 26 via a signal line 94.

[0092] The steering actuator unit 86 and the steering actuation unit 92 are both redundantly connected to the two power supply units 76, 78.

[0093] The braking system 10 shown in FIG. 1 is therefore a combined steering and braking system. It can also be referred to as a steering system, provided the appropriate components are available.

[0094] In normal operation, i.e. in an operating situation in which there is no defect or malfunction, the brake actuator units 12a, 12b, 12c, 12d and the steering actuator unit 86 are actuated by the first control unit 24 and/or the second control unit 26.

[0095] Signals generated by the brake actuation unit 48 and/or by the steering actuation unit 92, in particular driver requests relating to steering and braking, can be taken into account if this is necessary for the current driving operation of the associated vehicle.

[0096] At the same time, the control units 24, 26 can receive characteristic values and parameters from other controllers of the vehicle as well as sensor values detected by driving state sensors via the signal lines 72, 74 and take these into account when operating the brake actuator units 12a, 12b, 12c, 12d as well as the steering actuator unit 86.

[0097] Various failure scenarios are conceivable on the basis of this normal operation.

[0098] For example, one of the control units 24, 26 can fail.

[0099] In this case, however, all the brake actuator units 12a, 12b, 12c, 12d and the steering actuator unit 86 can be actuated by the other control unit 24, 26 in question. The braking system 10 is therefore still fully functional. This applies to both the braking function and the steering function.

[0100] Even if one of the power supply units 76, 78 fails, the braking system 10 continues to be fully functional, since it is then supplied with power by the other power supply unit 76, 78 in question. The same applies to the steering actuator unit 86.

[0101] If one of the brake actuator units 12a, 12b, 12c, 12d fails, these are obviously no longer available for producing a braking effect. In such a case, the braking system 10 works with the remaining three functional brake actuator units 12a, 12b, 12c, 12d and in this way can provide a braking power of approximately 70% compared to normal operation.

[0102] The same applies if one of the signal lines 32, 34, 36, 38, 40, 42, 44, 46 fails.

[0103] If the steering actuator unit 86 or one of the associated signal lines 84, 88 fails, the vehicle can be steered by selective braking interventions by the brake actuator units 12a, 12b, 12c, 12d. A steering function can therefore also be provided in this case.

[0104] FIG. 2 shows a variant of the braking system 10. In the following, only the differences from the arrangement in FIG. 1 will be discussed.

[0105] The signal lines 32, 34, 36, 38, 40, 42, 44, 46 are now combined to form a bus system, which is designated by 96 as a whole.

[0106] In addition, the power supply switches 80, 82 are no longer present.

[0107] In this context, the first control unit 24 is only coupled to the first power supply unit 76 and the second control unit 26 is only coupled to the second power supply unit 78.

[0108] The brake actuator units 12a, 12b, 12c, 12d are now subdivided into two subsets, with a first subset comprising the brake actuator units 12a and 12d being coupled only to the first power supply unit 76.

[0109] A second subset, which comprises the brake actuator units 12b and 12c; is only coupled to the second power supply unit 78.

[0110] Thus, if one of the energy supply units 76, 78 fails, only two of the brake actuator units 12a, 12b, 12c, 12d and one of the control units 24, 26 are available.

[0111] Otherwise, reference can be made to the explanations for the variant from FIG. 1.

[0112] Both the variant from FIG. 1 and the variant from FIG. 2 comprise a brake actuation unit 48 and a steering actuation unit 92; however, this is optional.

[0113] If neither a brake actuation unit 48 nor a steering actuation unit 92 is provided, the braking system 10 can be used exclusively in combination with an autonomous or partially autonomous driving mode of an associated vehicle.

[0114] A variant of the braking system 10 from FIG. 2 which does not require a brake actuation unit 48 or a steering actuation unit 92 is shown in FIG. 3.

[0115] All the exemplary arrangements have been described above as braking systems 10 which are designed as combined braking and steering systems. However, the components relating to the steering system, in particular the steering actuator unit 86 and the steering actuation unit 92, are to be regarded as optional. The braking system 10 can therefore also be designed as a pure braking system.