Vehicle braking equipment

Abstract

This invention relates to a vehicle braking device, comprising at least one brake adjustment system having a brake pressure adjuster, the brake pressure adjuster establishing hydraulic brake pressure upon braking request, the brake pressure enabling operation of wheel brakes, and the brake adjustment system being fixed to the vehicle body via retainers. According to the invention, an analysis unit (23) is provided to identify retainer failure, the analysis unit acquiring sensor signal curves (S) from internal sensors (17) installed in the brake adjustment system (BRS1, BRS2). ist In the analysis unit (23), signal comparison is performed, and the acquired sensor signal curve (S) is compared. ist ) and reference signal curve (S Ref The comparison was performed using the acquired sensor signal curve (S). ist ) relative to the reference signal curve (S Ref When there is a significant deviation (ΔS), the analysis unit (23) generates a retainer damage signal (S). HS ).

Description

Technical Field

[0001] The present invention relates to a braking device for a vehicle, and a method for identifying failure of a retainer / fixture in such a braking device. Background Technology

[0002] The vehicle's braking system can be implemented as a brake-by-wire system, in which there is no mechanical connection between the brake pedal and the brake adjustment system, but only an electrical signal connection. The brake adjustment system generates hydraulic braking pressure upon receiving a braking request (from the driver or the driving dynamics control unit), and this hydraulic braking pressure controls the vehicle's brakes.

[0003] Such a braking system can have two braking adjustment systems to provide a backup stage: a main braking adjustment system and a secondary braking adjustment system. In the event of a failure in the main braking adjustment system, the secondary braking adjustment system will assume the function of the main braking adjustment system. To minimize structural space requirements and reduce the number of components, these two braking adjustment systems can be fixed to the vehicle body using a common retaining element.

[0004] For safety reasons, it is essential to avoid simultaneous failure of both brake adjustment systems. This simultaneous failure occurs if the retaining elements for both brake adjustment systems are damaged, leading to tearing or leakage at the hydraulic connection after a period of time.

[0005] A device for evaluating the condition of a vehicle chassis is known from DE 10 2010 038 971 A1. A method for use in an electronic brake adjustment system is known from DE 102006 051 261 A1. A method for communication between two hydraulic brake adjustment systems in a braking system is known from DE 10 2020 206 436 A1. Summary of the Invention

[0006] Therefore, the object of the present invention is to provide a braking device in which damage to a retaining member can be easily identified, and at least one braking adjustment system is fixed to the vehicle body by means of the retaining member.

[0007] This invention is based on a braking device having at least one brake adjustment system with a brake pressure adjuster. The brake pressure adjuster establishes hydraulic brake pressure in the event of a braking request, which actuates the wheel brakes. The brake adjustment system is fixed to the vehicle body via a retainer. According to the invention, retainer failure, for example due to damage or loosening of the threaded connection between the retainer and the vehicle body, can be easily identified by equipping the braking device with an analysis unit that acquires sensor signal curves from internal sensors installed in the brake adjustment system. The analysis unit has a comparator module in which signal comparison is performed, wherein the acquired sensor signal curve is compared with a reference signal curve. If the acquired sensor signal curve deviates significantly from the reference signal curve, the analysis unit generates a retainer damage signal. This allows information to be sent to the user or workshop, for example based on warning lights, prompt text, or entries in service memory, so that the damage can be addressed.

[0008] Comparing the acquired sensor signal curve with a reference signal curve can be achieved by comparing internal and external sensor curves. Alternatively, a time-based comparison of the internal sensors can be performed (low amplitude before failure, high amplitude after failure). In another alternative, sensor values ​​in two braking adjustment systems can be compared based on vibration patterns (e.g., identical vibration before failure, reverse vibration after failure, amplitude, etc.). The above comparisons can also be applied to conventional ESC systems. These ESC systems are also not connected to the pedal but have retainers that may fail.

[0009] In common practice, various internal sensors are installed in brake regulation systems. The primary function of these internal sensors is to monitor the operation of the brake regulation system. Exemplarily, such internal sensors can be level sensors for the hydraulic fluid reservoirs of the brake regulation system. Alternatively and / or additionally, internal sensors can be acceleration sensors, based on which the driving dynamics control device manipulates the brake regulation system to implement braking interventions in driving dynamics. According to the present invention, such sensors within the brake regulation system are also used in a dual-function manner to identify retaining failure.

[0010] It should be emphasized that the present invention is not limited to the retaining member that supports both the main brake adjustment system and the auxiliary brake adjustment system as described at the beginning of the specification, but can also be applied to a retaining member that supports only a single brake adjustment system.

[0011] In a particularly preferred embodiment, the braking device can be implemented as a brake-by-wire system, providing a main brake adjustment system and a secondary brake adjustment system. In the event of a failure in the main brake adjustment system, the secondary brake adjustment system assumes the function of the main brake adjustment system. Preferably, both brake adjustment systems are jointly fixed to a retaining member.

[0012] For reliable analysis of sensor signals generated by internal sensors, the following approach is preferred: the analysis unit can be additionally connected to an external sensor, preferably an acceleration sensor, not installed in the brake adjustment system. This external sensor generates a vibration signal based on vehicle vibrations during operation. With the aid of the external sensor, correction of the sensor signal curve generated by the internal sensor can be performed. For example, before performing signal comparison, the vehicle vibration signal can be subtracted from the sensor signal curve of the internal sensor in the analysis unit. This results in a corrected sensor signal curve. Therefore, the corrected sensor signal curve eliminates the vibration component caused by vehicle vibrations. In this case, signal comparison can be performed in the analysis unit using the corrected sensor signal curve.

[0013] Alternatively and / or additionally, the analysis unit can only check for retainer failure if the vehicle vibration detected by external sensors is below a threshold. This prevents the erroneous generation of retainer damage signals due to excessive vehicle vibration, such as in situations with particularly rough road conditions. Otherwise, there is a risk that the sensor signal curves obtained from internal sensors would no longer be convincing regarding retainer damage due to excessively high vehicle vibration components. Furthermore, the analysis unit can also consider regulated conditions, such as ABS braking. Here, the vibration of the device after retainer failure is significantly different from the vibration before failure.

[0014] As described above, in the comparator module of the analysis unit, signal comparison is performed between the signal from the internal sensor and a reference signal. According to one embodiment, the reference signal curve can be the signal curve of the internal sensor, which occurs during normal driving operation and when the components are intact. The reference signal curve can be stored in the analysis unit as a theoretical value.

[0015] In another embodiment, internal sensors can be installed in the main brake adjustment system and the auxiliary brake adjustment system, respectively. These two internal sensors can be integrated in case of retainer failure. In this case, the sensor signal curves of the two internal sensors can be compared with each other in the analysis unit. Therefore, the sensor signal curve of one sensor forms a reference signal curve for the sensor signal curve of the other sensor. Attached Figure Description

[0016] The invention is described in detail below with reference to the accompanying drawings, wherein:

[0017] Figure 1 A braking device installed in a vehicle according to a first embodiment is shown;

[0018] Figure 2 The signal curves of the internal sensors of the braking device are shown;

[0019] Figures 3 to 5 The illustration shows a parallel according to another embodiment. Figure 1 A comparable view. Detailed Implementation

[0020] Figure 1 The diagram illustrates a schematic of a braking device installed in a vehicle, to the extent necessary for understanding the invention. This braking device is implemented as a brake-by-wire system, more specifically having a main brake regulating system BRS1 and a secondary brake regulating system BRS2. Each of the two brake regulating systems BRS1 and BRS2 has a brake pressure adjuster (not shown), such as a piston pump or impeller pump. Upon a braking request, the brake pressure adjuster generates hydraulic braking pressure, which is used to operate the vehicle's wheel brakes B1 to B4. Figure 1 In this configuration, two brake adjustment systems, BRS1 and BRS2, ​​are equipped with hydraulic fluid containers 1. These containers are positioned above the main brake adjustment system BRS1 and connected to both systems. The main brake adjustment system BRS1 is connected to the auxiliary brake adjustment system BRS2 via hydraulic lines 5. An additional hydraulic line 7 extends from the auxiliary brake adjustment system BRS2 to the wheel brakes B1 to B4.

[0021] Each of the two brake adjustment systems, BRS1 and BRS2, ​​has a controller 9, 11. The controllers 9, 11 of both brake adjustment systems BRS1 and BRS2 are electrically connected to the electronic brake pedal 13. Furthermore, the controller 11 of the secondary brake adjustment system BRS2 can be electrically controlled by the driving dynamics control device 15. In the event of a failure in the primary brake adjustment system BRS1, the secondary brake adjustment system BRS2 assumes the functions of the primary brake adjustment system BRS1.

[0022] The two brake adjustment systems BRS1 and BRS2 are not directly fixed to the vehicle body 19, but are fixed by means of a separate retainer 21, on which the two brake adjustment systems BRS1 and BRS2 are fixed. The retainer 21 is connected to the vehicle body 19 via a threaded connection structure 22, while the two brake adjustment systems BRS1 and BRS2 are mounted on the retainer 19 via a threaded connection structure 24.

[0023] exist Figure 1The system includes an analysis unit 23 for identifying retaining failures, and this unit is connected to a sensor 17 within the brake adjustment system. Figure 1 In this configuration, internal sensor 17 is a liquid level sensor. The function of this liquid level sensor is to monitor the liquid level of the hydraulic fluid in the hydraulic fluid container 1. This is achieved by analyzing the sensor signal curve S of internal sensor 17. ist The analysis unit 23 identifies retention failure. For this purpose, the analysis unit 23 stores a reference signal curve 25 from the internal sensor 17, which is formed during normal driving operation with the retention 21 intact. Signal comparison is performed in the comparator module 27 of the analysis unit 23, where the acquired sensor signal curve S... ist Compared with the reference signal curve S stored in the analysis unit 23 Ref Compare them.

[0024] Figure 2 The reference signal curve S is shown as an example in the time chart on the left. Ref This reference signal curve is formed under the condition that component 21 remains intact during normal driving operation. The current sensor signal curve S of internal sensor 17 is shown in the time graph on the right. ist For the sake of simplicity, in Figure 2 The two signal curves S Ref and S ist They are shown as continuous sine waves, respectively. In reality, these two signal curves S... Ref and S ist It consists of multiple superimposed sine waves with different frequencies and amplitudes. In the two signal curves S... Ref and S ist In the comparison, Figure 2 A noticeable deviation ΔS can be observed, which may occur, for example, in cases of retainer failure or loosening of threaded connections 22 and 24. In the presence of such a noticeable deviation ΔS, analysis unit 23 generates a retainer failure signal S. HS The fault signal of the retainer is used to inform the user or workshop, for example, through a warning light, information text, or an entry in the service memory.

[0025] Figure 3 The second embodiment is shown, and its basic structure and operation are substantially the same as those of the foregoing embodiments. Figure 1 compared to, Figure 3The braking device has an acceleration sensor as an internal sensor 17, which is installed in the control unit 11 of the secondary brake adjustment system BRS2. The acceleration sensor is signal-connected to the analysis unit 23 and the driving dynamics control device 15. Based on the lateral and / or longitudinal acceleration obtained by the acceleration sensor, the driving dynamics control device 15 controls the secondary brake adjustment system BRS2 to perform dynamic braking intervention. Figure 3 In the example, the analysis unit 23 detects retention failure based on the lateral and / or longitudinal acceleration acquired by the acceleration sensor 17.

[0026] Regarding the reliable identification of such retainer failure conditions, Figure 3 The analysis unit 23 is additionally connected to an external sensor 29, preferably an acceleration sensor, which is not installed in the brake adjustment systems BRS1 and BRS2. This external sensor acquires vehicle vibrations during operation. Due to the vehicle vibrations, the external sensor 29 generates a vehicle vibration signal S. F .exist Figure 3 In the analysis unit 23, a subtraction element 31 is included. Before performing signal comparison in the comparator module 27, the sensor signal curve S from the internal sensor 17 is analyzed. ist Subtract vehicle vibration signal S F Thus, the corrected sensor signal curve S is obtained. mod The corrected sensor signal curve eliminates the vibration component caused by vehicle vibration. Corrected sensor signal curve S mod It is fed to comparator module 27. There, as... Figure 1 As shown, signal comparison is performed. When the deviation ΔS is significantly large, a retainer damage signal S is generated. HS Using the cleaned and corrected sensor signal curve S mod This can prevent the erroneous generation of retainer damage signals S caused by excessive vehicle vibration. HS .

[0027] The external sensor 29 can be installed in various other components of the vehicle, such as in the airbag controller. Exemplarily, the external sensor 29 can be a 3D sensor, a longitudinal or lateral acceleration sensor, or a liquid level sensor.

[0028] Figure 4 An alternative embodiment is shown, which also avoids the erroneous generation of a retainer damage signal S (due to excessive vehicle vibration). HS . Figure 4 The embodiments are basically the same as Figure 1 The implementation is consistent with the previous one. (And) Figure 1 The difference is that, in Figure 4In this configuration, comparator module 27 only begins signal comparison when the vehicle vibration detected by external acceleration sensor 29 is below a threshold. This prevents the erroneous generation of a retainer damage signal S due to excessive vehicle vibration—for example, in cases of particularly rough road conditions. HS .

[0029] exist Figure 5 In this embodiment, an internal sensor 17, serving as an acceleration sensor, is installed in each of the controllers 9 and 11 of the braking adjustment systems BRS1 and BRS2. In this case, the sensor signal curves S of the two internal sensors 17... ist1 S ist2 The signals are compared in the comparator module 27 of the analysis unit 23. Therefore, the analysis unit 23 does not store the reference signal curve as in the first embodiment. Instead, it stores the sensor signal curve S of the internal sensor 17. ist1 A sensor signal curve S was formed for another internal sensor 17. ist2 The reference signal curve. In the two sensor signal curves S ist1 S ist2 When there is a significant deviation ΔS between the two components, the analysis unit 23 generates a retainer damage signal S. HS .

[0030] List of reference numerals in the attached diagram:

[0031] 1. Hydraulic fluid container

[0032] 5. Hydraulic circuit

[0033] 7. Hydraulic circuit

[0034] 9, 11 Controllers

[0035] 13 Electronic brake pedal

[0036] 15. Driving dynamics control device

[0037] 17 Internal Sensors

[0038] 19. Body

[0039] 22 Threaded connection

[0040] 23 Analysis Unit

[0041] 24 Threaded connection

[0042] 25 benchmarks

[0043] 27 Comparator Module

[0044] 29 External Sensors

[0045] 31 Subtractors

[0046] BRS1 Main Brake Adjustment System

[0047] BRS2 auxiliary braking adjustment system

[0048] B1 to B4 wheel brakes

[0049] S ist Sensor signal curve

[0050] S Ref Reference signal curve

[0051] ΔS deviation

[0052] S mod Corrected sensor signal curve

[0053] S F Vehicle vibration signal

[0054] S HS Retainer damage signal

Claims

1. A braking device for a vehicle, the braking device comprising at least one brake regulating system (BRS1, BRS2), the at least one brake regulating system having a brake pressure adjuster, the brake pressure adjuster establishing a hydraulic brake pressure in the presence of a braking request, the brake pressure being used to operate wheel brakes (B1 to B4), wherein, The brake adjustment system (BRS1, BRS2) is fixed to the vehicle body (19) via a retainer (21). Its features are, For the purpose of identifying a failure of the retaining element, there is provided an evaluation unit (23) which obtains a sensor signal curve (S ist ) from an internal sensor (17) installed in the brake regulation system (BRS1, BRS2). Signal comparison is performed in the analysis unit (23), wherein the acquired sensor signal curve (S) is compared. ist ) and reference signal curve (S Ref Compare the obtained sensor signal curves (S) with the obtained sensor signal curves (S). ist ) relative to the reference signal curve (S Ref When there is a significant deviation (ΔS), the analysis unit (23) generates a retainer damage signal (S). HS ), in, Reference signal curve (S) Ref ) is the signal curve of the internal sensor (17) that appears during normal driving operation with the retaining element (21) intact, or An internal sensor (17) is installed in each of the two braking adjustment systems (BRS1, BRS2). The sensor signal curves of the two internal sensors (17) are compared with each other in the analysis unit (23), so that the sensor signal curve (S) of one internal sensor (17) is compared with the sensor signal curve (S). ist1 ( ) forms a reference signal curve for the sensor signal curve of another internal sensor (17).

2. The braking device according to claim 1, characterized in that, The internal sensor (17) installed in the brake regulation system (BRS1, BRS2) is the level sensor of the hydraulic fluid container (1) of the brake regulation system (BRS1, BRS2).

3. The braking device according to claim 1 or 2, characterized in that, The sensor (17) installed in the brake adjustment system (BRS1, BRS2) is an acceleration sensor, and the driving dynamics control device (15) uses the acceleration sensor to control the brake adjustment system (BRS1, BRS2) to implement braking intervention.

4. The braking device according to claim 1 or 2, characterized in that, The braking device is implemented as a brake-by-wire system, wherein the brake adjustment system (BRS1) forms the main brake adjustment system and additionally provides the auxiliary brake adjustment system (BRS2). When the main brake adjustment system (BRS1) fails, the auxiliary brake adjustment system assumes the function of the main brake adjustment system (BRS1). The two brake adjustment systems (BRS1, BRS2) are jointly fixed on the retainer (21).

5. The braking device according to claim 1 or 2, characterized in that, The analysis unit (23) is additionally connected to an external sensor (29) not installed in the brake adjustment system (BRS1, BRS2). In the event of vehicle vibration during operation, the external sensor generates a corresponding vehicle vibration signal (S). F Before performing signal comparison, the analysis unit (23) analyzes the sensor signal curve (S) from the internal sensor (17). ist Subtract the vehicle vibration signal (S) from the input. F Therefore, a corrected sensor signal curve (S) is formed. mod The corrected sensor signal curve eliminates vibration components belonging to vehicle vibration. mod Perform a signal comparison.

6. The braking device according to claim 5, characterized in that, The analysis unit (23) checks for retainer failure only when the vehicle vibration detected by the external sensor (29) is below a threshold, thereby preventing the erroneous generation of a retainer damage signal (S) due to excessive vehicle vibration. HS ).

7. A method for identifying retention failure in a braking device according to any one of claims 1-6, The sensor signal curve (S) is obtained from the internal sensor (17) installed in the brake adjustment system (BRS1, BRS2). ist ), The acquired sensor signal curve (S) ist ) and reference signal curve (S Ref Compare the obtained sensor signal curves (S) with the obtained sensor signal curves (S). ist ) relative to the reference signal curve (S Ref If there is a significant deviation (ΔS), the analysis unit (23) generates a retainer damage signal (SHS). in, Reference signal curve (S) Ref The signal curve of the internal sensor (17) appears during normal driving operation with the retaining element (21) intact. or An internal sensor (17) is installed in each of the two braking adjustment systems (BRS1, BRS2). The sensor signal curves of the two internal sensors (17) are compared with each other in the analysis unit (23), so that the sensor signal curve (S) of one internal sensor (17) is compared with the sensor signal curve (S). ist ( ) forms a reference signal curve for the sensor signal curve of another internal sensor (17).

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