Parking brake of a vehicle with backup power supply and method for providing an electrical backup energy supply for a parking brake
Patent Information
- Authority / Receiving Office
- WO · WO
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2026-01-09
- Publication Date
- 2026-08-13
Smart Images
Figure EP2026050447_13082026_PF_FP_ABST
Abstract
Description
[0001] 2023P00190 DE 10.02.2025
[0002] 1
[0003] DESCRIPTION
[0004] Parking brake of a vehicle with backup power supply and method for providing an electrical backup power supply for a parking brake
[0005] The invention relates to an electropneumatic parking brake of a vehicle, in particular a commercial vehicle according to the preamble of claim 1, a method for providing an electrical backup power supply for an electropneumatic parking brake (EPB) of a vehicle according to the preamble of claim 9, and a computer program with program code that causes the parking brake (EPB) to execute the method according to claim 13.
[0006] For example, DE 10 2015 114 176 B3 discloses a generic electropneumatic parking brake and a generic method. There, the electropneumatic parking brake comprises a bistable pneumatic relay valve that can assume two safe states even in the event of a power failure: a vented first safe state, which allows the commercial vehicle to be driven, and a vented second safe state, which causes the commercial vehicle to stand still. Therefore, if the power fails in either of the two safe states, the bistable relay valve maintains the respective first or second safe state.
[0007] One problem, however, is the so-called "gray point sticking" in relation to an intermediate state between the first and second safe states of the relay valve, which occurs, for example, during an auxiliary braking function of the parking brake. In the event of a power failure when the relay valve is in such an intermediate state, a piston of the relay valve may remain in an intermediate position (grey point), resulting in an unchanged parking brake pressure for some time.
[0008] Over time, unavoidable minor leaks in the parking brake system can cause the relay valve piston to switch to either the first safe state or the second safe state. This can be particularly problematic when the commercial vehicle is in motion and then 2023P00190 DE
[0009] 2
[0010] There is a risk that the relay valve will switch to the vented second safe state and then apply the parking brake while driving, which can lead to sudden overbraking of the commercial vehicle and consequently to unstable driving conditions.
[0011] The objective is therefore to increase the safety of an electropneumatic parking brake in the event of a power failure or malfunction. This objective is achieved by an electropneumatic parking brake according to claim 1, a method according to claim 9, and a computer program product according to claim 13.
[0012] The dependent claims relate to advantageous embodiments of the subject matter of the independent claims.
[0013] General description of the invention
[0014] In a first aspect, the invention presents an electropneumatic parking brake (EPB) of a vehicle comprising a primary power supply unit, an electronic parking brake control unit supplied with electrical energy by the primary power supply unit, a valve assembly with multiple solenoid valves controlled by the electronic parking brake control unit, a spring-applied parking brake that can be vented and released by the valve assembly, and a backup system configured to bring the electropneumatic parking brake into a safe state or to switch it on, wherein the backup system comprises:
[0015] a) Detection means configured at least to detect a fault, malfunction or failure of the electronic parking brake control and / or the primary power supply unit and to generate a fault signal when they detect the fault, malfunction or failure, and
[0016] b) a storage device independent of the primary power supply unit for storing sufficient electrical energy to bring or switch the electropneumatic parking brake into the safe state, and
[0017] c) a switching device which is at least configured to supply the electrical energy to the storage device of the valve device by switching, when the switching device
[0018] c1) receives the interference signal from the detection means, or 2023P00190 DE
[0019] 3
[0020] c2) receives a switching signal for this purpose from a control unit independent of the parking brake control.
[0021] A failure, malfunction, or fault in the electronic parking brake control unit can result from a failure of the primary electrical power supply unit that provides the electronic parking brake control unit with electrical energy. A fault, malfunction, or failure of the electronic parking brake control unit can be detected by self-monitoring. In this case, the detection means can be integrated into the electronic parking brake control unit. Alternatively, a fault, malfunction, or failure of the electronic parking brake control unit can be detected, for example, by external monitoring. In at least this case, the detection means for the electronic parking brake control unit can be a separate unit.
[0022] The control unit, independent of the parking brake control, can generate the switching signal, for example, depending on whether at least a semi-autonomous or autonomous vehicle control system has a fault, malfunction, or has failed. In such a case, establishing a safe parking state or ensuring the vehicle remains stationary is particularly desirable.
[0023] The spring-applied brake preferably comprises at least one (passive) spring-applied brake cylinder, which releases and applies the spring-applied brake.
[0024] The valve assembly is then normally controlled by the electronic parking brake control unit to pressurize or vent the spring-applied brake, and in particular the at least one spring-applied brake cylinder. In the event of a power failure of the primary power supply unit or a detected fault in the parking brake control unit, the valve assembly, in particular at least one specific or selected solenoid valve of the valve assembly, is energized by the electrical energy of the storage device to establish or maintain the safe state of the vehicle. 2023P00190 DE
[0025] 4
[0026] The supply of electrical energy from the storage device to at least one solenoid valve of the valve assembly can cause the at least one solenoid valve to vent or release the spring-applied parking brake. This ensures the (particularly first) safe (released) state of the electropneumatic parking brake or the spring-applied parking brake when the vehicle is in motion and prevents the electropneumatic parking brake from automatically engaging in the event of a power failure, which could lead to dangerous instabilities. Furthermore, this also ensures the (particularly second) safe (engaged) state of the electropneumatic parking brake or the spring-applied parking brake when the vehicle is stationary and prevents the electropneumatic parking brake from releasing in the event of a power failure, which could cause the vehicle to roll away dangerously.
[0027] The vehicle's driving state can be defined as a state of motion of the commercial vehicle in which the vehicle's speed is above a predefined value of 10 km / h, 7 km / h, 5 km / h or 3 km / h, or in which the speed is greater than zero.
[0028] The standstill or halt of the vehicle can be defined as a state of the vehicle in which the speed of the vehicle is equal to or less than the predefined value of 10 km / h, 7 km / h, 5 km / h or 3 km / h, or in which the speed is close to zero.
[0029] The valve assembly of the electropneumatic parking brake can also include an inlet / outlet solenoid valve combination, in particular with an inlet solenoid valve and an outlet solenoid valve, as well as a pneumatically controlled relay valve, wherein the inlet / outlet valve combination is provided to generate a control pressure at a pneumatic control input of the relay valve.
[0030] In particular, in the case of the electro-pneumatic parking brake (EPB), the inlet / outlet valve combination can be configured to connect the pneumatic control input of the relay valve to a compressed air reservoir or a pressure sink.
[0031] In the normal case, the valve device is preferably controlled by the parking brake control to generate a control pressure for the pneumatic control input of the relay valve, in order to activate the spring-applied brake and, in particular, the at least one 2023P00190 DE, depending on the control pressure present at the pneumatic control input.
[0032] 5
[0033] The spring-applied brake cylinder is connected to the compressed air reservoir or the pressure sink. As explained above, in the event of a power failure of the primary power supply unit or a detected fault in the parking brake control, the valve assembly, in particular at least one specific solenoid valve of the valve assembly, is energized by electrical energy from the storage device in order to establish or maintain the safe state of the vehicle.
[0034] According to a preferred embodiment, the detection means may be further configured to detect a driving state or a standstill of the vehicle and to generate a driving state signal depending thereon.
[0035] The switching device can then be configured to supply the electrical energy from the storage device to at least one specific (selected) solenoid valve of the valve assembly, in particular the inlet solenoid valve or the outlet solenoid valve, wherein the selection of the at least one solenoid valve depends on the driving condition signal, i.e., in particular, on whether the driving condition or the vehicle's standstill has been detected by the detection means. The specific (selected) solenoid valve can, in particular, be an inlet solenoid valve or an outlet solenoid valve.
[0036] Alternatively, the valve assembly may include a solenoid valve with an inlet switching position and an outlet switching position. The switching device may then be configured to select or determine the inlet switching position or the outlet switching position of this solenoid valve, with this determination or selection depending on the driving condition signal, i.e., in particular, depending on whether the vehicle's driving condition or standstill has been detected by the detection means.
[0037] In particular,
[0038] a) In the detected driving state, the safe state of the electro-pneumatic parking brake (EPB) is the released state of the spring-applied parking brake, and b) in the detected standstill state, the safe state of the electro-pneumatic parking brake (EPB) is the applied state of the spring-applied parking brake. The switching device can also be configured to
[0039] a) in the detected driving state of the vehicle, the inlet-outlet solenoid valve combination is moved to a ventilation position, and um2023P00190 DE
[0040] 6
[0041] b) to switch the inlet-outlet solenoid valve combination to a venting position when the vehicle is detected to be stationary.
[0042] The switching device can be configured for further training purposes to
[0043] a) to open the intake solenoid valve and close the exhaust solenoid valve in the detected driving state of the vehicle, or to switch the solenoid valve with the intake switching position and the exhaust switching position to the intake switching position, and to
[0044] b) to close the inlet solenoid valve and open the exhaust solenoid valve when the vehicle is detected to be stationary, or to switch the solenoid valve with the inlet switching position and the exhaust switching position to the exhaust switching position.
[0045] Additionally, the switching device can be configured to supply the electrical energy of the storage device to at least one solenoid valve of the valve assembly, in particular directly, when a fault or power failure and a standstill of the vehicle are detected, wherein the (in particular second) safe state of the electropneumatic parking brake at standstill is the applied state of the spring-applied parking brake.
[0046] The supply of electrical energy from the storage device to at least one solenoid valve of the valve assembly can cause the at least one solenoid valve of the valve assembly to vent the spring-applied parking brake. This ensures the (particularly second) safe (engaged) state of the electropneumatic parking brake or the spring-applied parking brake, namely that in the event of a power failure or malfunction and when the vehicle is detected as stationary, the electropneumatic parking brake automatically engages.
[0047] According to one variant, the detection means can include the electronic parking brake control and / or a (separate) detection unit. Preferably, the detection of the vehicle's standstill and / or driving state by the detection unit and / or the electronic parking brake control occurs continuously during vehicle operation and also shortly before a power failure, so that information about the vehicle's standstill or driving state is preferably retained even after the power failure, particularly in a buffer. 2023P00190 DE
[0048] 7
[0049] The switching device can also be designed to transfer the electrical energy of the storage device
[0050] a) the electronic parking brake control of the electro-pneumatic parking brake (EPB) and / or
[0051] b) to supply at least one solenoid valve
[0052] when the power failure or malfunction and the driving condition or standstill are detected by the detection means.
[0053] The backup system may include a safety power supply unit configured to be charged by the storage device and to provide emergency power for the detection means and / or the switching device.
[0054] The storage device of the backup system may also include at least one capacitor or be designed as a capacitor.
[0055] According to one variant, a first capacitor may also be provided and configured to energize a first solenoid valve of the valve assembly, in particular an inlet solenoid valve, to switch it to a venting position when a power failure or malfunction and the vehicle's driving state are detected. Additionally, a second capacitor may be provided and configured to energize a second solenoid valve of the electropneumatic parking brake, in particular an outlet solenoid valve, to switch it to a venting position when a power failure and the vehicle's standstill are detected.
[0056] The backup system can also be a separate component or integrated into the electropneumatic parking brake.
[0057] According to a further aspect, the invention also presents a method for providing an electrical backup power supply for an electropneumatic parking brake of a vehicle, which comprises at least one primary power supply unit, an electronic parking brake control unit supplied with electrical energy by the primary power supply unit, a valve assembly with several solenoid valves controlled by the electronic parking brake control unit, and a spring-applied parking brake that can be pressurized and vented by the valve assembly, in order to provide, with the aid of the electrical backup power supply, an electropneumatic parking brake.
[0058] 8
[0059] The method includes at least the following steps: a) Detecting a fault or failure of the electronic parking brake control and / or the primary power supply unit and generating a fault signal upon detection of the fault or failure by detection means;
[0060] b) Storing sufficient electrical energy by means of a storage device independent of the primary power supply unit to bring or switch the electropneumatic parking brake into the safe state;
[0061] c) Supplying the electrical energy of the storage device to the valve device by switching a switching device when the switching device
[0062] c1) receives the interference signal from the detection means, or
[0063] c2) receives a switching signal for this purpose from a control unit independent of the parking brake control.
[0064] The detection devices can also generate a driving condition signal depending on whether they detect a driving condition or a standstill of the vehicle.
[0065] The switching device can also supply the electrical energy of the storage device to at least one specific solenoid valve of the valve assembly, the determination of the at least one solenoid valve depending on the driving condition signal.
[0066] Alternatively, if the valve assembly includes a solenoid valve having an inlet switching position and an outlet switching position, the switching device is configured to select or determine the inlet switching position or the outlet switching position of this solenoid valve, with this determination or selection depending on the driving condition signal, i.e., in particular, depending on whether the driving condition or the vehicle's standstill has been detected by the detection means. 2023P00190 DE
[0067] 9
[0068] The procedure may also include provisions that
[0069] a) in the detected driving condition, the released state of the spring-applied parking brake is used as the safe state of the electro-pneumatic parking brake, and
[0070] b) in the detected standstill, the engaged state of the spring-applied parking brake is used as the safe state of the electropneumatic parking brake.
[0071] The method can also include supplying electrical energy from the storage device to at least one solenoid valve of the valve assembly via the switching device when a power failure or malfunction and a standstill of the vehicle are detected, wherein the engaged state of the spring-applied parking brake is used as the (in particular second) safe state of the electropneumatic parking brake when the commercial vehicle is stationary.
[0072] In this case (power failure or malfunction and standstill), the supply of electrical energy from the storage device to the at least one solenoid valve of the valve assembly causes the at least one solenoid valve of the valve assembly to vent the spring brake.
[0073] As described above, at least one capacitor can also be used for the storage device. The capacitor's capacitance can be in the range of 100–300 pF, or approximately 220 pF.
[0074] Furthermore, the invention also includes a computer program with program code that causes the electropneumatic parking brake (EPB), in particular the backup system described above, to execute the method described above when the computer program is executed on a processor.
[0075] Embodiments of the invention therefore provide a backup storage device, in particular a backup energy storage device, such as at least one capacitor, which is arranged and configured to store sufficient energy to actuate the solenoid valve(s) of the electropneumatic parking brake, so that it preferably switches within a short time period (for example, within 50 ms to 100 ms). 2023P00190 DE
[0076] 10
[0077] At least one capacitor can be charged or actively discharged within milliseconds, and the capacitor's status can be transmitted to the electronic parking brake control.
[0078] Preferably, when the vehicle is stationary as detected by the detection devices and / or the electronic parking brake control, the at least one capacitor of the storage device is discharged and, in particular, held in the discharged state to prevent unintentional application of the spring-applied parking brake when the vehicle is in motion. Conversely, the at least one capacitor of the storage device is preferably charged when the vehicle is in motion. Discharge of the at least one capacitor, in the sense of a direct supply of the stored electrical energy to the at least one solenoid valve via the switching device, occurs when the power failure and the vehicle being in motion are detected by the detection devices.The electrical energy of the at least one capacitor is then preferably used for excitation or current energizing, for example, an inlet solenoid valve of the electropneumatic parking brake, in order to ventilate or keep ventilated the spring-applied brake in the driving state, thereby establishing a first safe (driving) state.
[0079] Additionally, it can be provided that the at least one capacitor of the storage device is discharged and held in the discharged state when the vehicle is in a driving state detected by the detection devices, but charged when the vehicle is stationary, also detected by the detection devices. Discharge of the at least one capacitor, in the sense of a direct supply of the stored electrical energy to the at least one solenoid valve via the switching device, occurs when the power failure and the vehicle's stationary state are detected by the detection devices. The electrical energy of the at least one capacitor is then used, for example, to excite or energize an outlet solenoid valve of the valve assembly in order to vent or keep vented the spring-applied brake when stationary, thereby establishing a second safe (parking) state.
[0080] To ensure that both safe states (parked and driving states) can be achieved in the event of a power failure or malfunction, the storage device can, for example, contain 2023P00190 DE
[0081] 11
[0082] at least one first capacitor to bring about a safe driving state and at least one second capacitor to bring about a safe standstill must be provided.
[0083] The first capacitor of the storage device can then be discharged when the vehicle is detected as stationary and charged when the vehicle is detected as moving. Conversely, the second capacitor of the storage device can be charged when the vehicle is detected as stationary and discharged when the vehicle is detected as moving.
[0084] Exemplary embodiments of the invention are described below with reference to the accompanying figures. The figures show:
[0085] Fig. 1 shows a preferred embodiment of an electropneumatic parking brake (EPB) with a backup system;
[0086] Fig. 2 is a schematic flowchart of a preferred embodiment of a method for providing an electrical backup power supply for the electropneumatic parking brake of Fig. 1; Fig. 3 is a schematic circuit diagram of a preferred embodiment of a valve assembly of the electropneumatic parking brake of Fig. 1.
[0087] Description of the exemplary implementations
[0088] Fig. 3 shows a schematic circuit diagram of a valve assembly 10 of a preferred embodiment of an electropneumatic parking brake (EPB) for a commercial vehicle. The electropneumatic parking brake (EPB) comprises, for example, a relay valve 80, an inlet solenoid valve 71, and an outlet solenoid valve 72, each here, for example, configured as a monostable 2 / 2-way solenoid valve, with a closed position and an open position. The inlet solenoid valve 71 and the outlet solenoid valve 72 are preferably normally closed (NC) valves, i.e., they switch to the closed position when de-energized and to the open position when energized.
[0089] Furthermore, a compressed air supply 61 provides working compressed air for the relay valve 80 and for the inlet solenoid valve 71 via a check valve 65, a supply connection 89 and a supply line 86. In the open position, the inlet solenoid valve 71 connects a supply line 86 to a control pressure line 85, to which a 2023P00190 DE
[0090] 12
[0091] The pneumatic control input 81 of the relay valve 80 is connected. In the open position, the outlet valve 72 connects the control pressure line 85 to a pressure sink or vent 30.
[0092] The valve assembly 10, specifically its inlet solenoid valve 71 and outlet solenoid valve 72, is controlled by an electronic parking brake control unit 60 shown in Fig. 1. This unit energizes and de-energizes the valve assembly, thereby generating a pneumatic control pressure for the control input 81 of the relay valve 80. When the inlet solenoid valve 71 is energized or activated, it vents the control input 81, and the outlet solenoid valve 72 vents the control input 81. The electronic parking brake control unit 60 is supplied with electrical current by a primary power supply unit 50, for example, a power supply unit.
[0093] The relay valve 80 is connected to spring-applied brake cylinders of a spring-applied brake via a spring-applied brake assembly 10 at an outlet 84. These cylinders are either vented via a vent or pressure sink (when stationary) or pressurized via the supply line 86 (when driving). The pressure in the control pressure line 85 is detected by a pressure sensor 76 and then monitored, for example, by the electronic parking brake control unit 60.
[0094] A first safe state of the relay valve 80 is ensured by a preload spring, which leads to a (pressureless or vented) basic position of the relay valve 80 in which the spring-applied brake is vented (standstill).
[0095] A second safe state of the relay valve 80 is stabilized by connecting the control pressure line 85, which is connected to the control input 81, to the output 84 of the relay valve 80, in order to feed the output pressure back to the control input 81 as pneumatic control pressure. This ensures that the outlet 84 and the control input 81 remain stably in the same state (vented or vented) – at least as long as the input and output solenoid valves 71, 72 are in their standard, closed position, even if a leak is present. As described above, a problem can arise in the so-called “gray point sticking” of the relay valve 80 in an intermediate state between the first safe state and the second safe state, which is assumed, for example, during an auxiliary braking function of the electropneumatic parking brake. For example, in the event of a failure of a primary power supply unit 50 of the 2023P00190 DE
[0096] 13
[0097] In the electronic parking brake control 60, in which the relay valve 80 is in such an intermediate state, it can happen that a piston of the relay valve 80 remains in an intermediate position (grey point), which leads to a parking brake pressure that remains unchanged for some time.
[0098] Over time, unavoidable minor leaks in the electro-pneumatic parking brake (EPB) can cause the piston of relay valve 80 to switch to either the first safe state or the second safe state. This can be particularly problematic when the vehicle is in motion, as there is a risk that relay valve 80 will switch to the vented second safe state, thereby engaging the electro-pneumatic parking brake (EPB) while driving. This can lead to sudden overbraking of the vehicle and consequently to unstable driving conditions.
[0099] To solve this problem, a backup system 100, schematically depicted in Fig. 1, is provided, which, as shown in Fig. 1, is implemented, for example, as a separate system. Alternatively, the backup system 100 can also be integrated into the electro-pneumatic parking brake (EPB) and, for example, be designed as a single unit with it. According to an exemplary embodiment, the backup system 100 can be integrated into a potentially existing circuit board and comprise one or more electronic components of the electronic parking brake (EPB), such as the electronic parking brake control unit 60 and / or the power supply unit 50.
[0100] For simplicity, Fig. 1 shows only the primary power supply unit 50, the electronic parking brake control unit 60, and the valve assembly 10 from Fig. 3 of the electronic parking brake (EPB). The valve assembly 10 is configured to set a pneumatic parking brake pressure in the EPB based on control inputs from the electronic parking brake control unit 60. For this purpose, the electronic parking brake control unit 60 actuates at least one solenoid valve 70 of the valve assembly 10 from Fig. 3, which in this case can be the inlet solenoid valve 71 and / or the outlet solenoid valve 72.
[0101] The backup system 100 is configured to provide an electrical backup power supply for the electro-pneumatic parking brake (EPB) such that 2023P00190 DE
[0102] 14
[0103] Even in the event of a power failure of the primary power supply unit 50 of the electropneumatic parking brake (EPB), a safe state is ensured. For this purpose, the backup system 100 comprises, for example, a detection unit 110, a storage device 120, and a switching device 140, as shown in Fig. 1.
[0104] The detection unit 110 is designed to detect a power failure of the primary power supply unit 50 and then generate a fault signal Sst. For this purpose, the detection unit 110 can be connected to the primary power supply unit 50. Furthermore, the detection unit 110 can, for example, be connected to a signal port 55 of the backup system 100, which is connected, for example, to a (vehicle) data bus 93.
[0105] The vehicle data bus 93 may contain speed signals Sv relating to the vehicle's speed. The parking brake control unit 60 and / or the detection unit 110 may be configured to detect the vehicle's state of motion (for example, driving at a speed above 7 km / h). Thus, the detection unit 110 may, for instance, be configured to recognize a stationary or driving state of the vehicle based on the speed signals Sv and generate a driving state signal Sz accordingly.
[0106] Switching signals St from an external electronic control 95 can also be present on the vehicle data bus 93, which are then controlled via the signal connection 55 into the backup system 100 and from there forwarded to the switching device 140.
[0107] The storage device 120 is configured to store sufficient electrical energy to switch or bring the electropneumatic parking brake EPB into a safe state by switching at least one solenoid valve 70 of the valve assembly 10.
[0108] Preferably, the storage device 120 provides the electrical energy for the switching device 140, which is designed to establish or disconnect a current path from the storage device 120 to the at least one solenoid valve 70. The switching device 140 is configured to supply the electrical energy of the storage device 120 to the electropneumatic parking brake EPB when 2023P00190 DE
[0109] 15
[0110] a) a failure or fault of the primary power supply unit 50 and / or the electronic parking brake control 60 is detected, for example, by the detection unit 110, which then generates the fault signal Sst and feeds it into the switching device 140, and / or if
[0111] b) The external control 95 generates the switching signal for the switching device 140. The capacity of the storage device 120 is preferably dimensioned based on the electrical energy required to energize the at least one solenoid valve 70 at least once, for example, to switch it. Furthermore, the storage device 120 can include one or more capacitors, as these can be charged and discharged quickly. For example, simulations have shown that a possible activation time of a solenoid valve 70 is in the range of 100 microseconds (or less), which is sufficient in the event of a failure of the power supply unit 50 to bring about the safe state of the electropneumatic parking brake by switching the at least one solenoid valve 70.
[0112] The following describes the operation of the electropneumatic parking brake EPB and in particular the backup system 100.
[0113] If, for example, a failure of the primary power supply unit 50 and the driving state of the commercial vehicle are detected by the detection unit 110 and / or the electronic parking brake control 60, the detection unit 110 feeds the fault signal Sst and the driving state signal Sz, which now indicates the detected driving state, into the switching device 140. Alternatively or in parallel, the external control unit 95 can feed the switching signal St into the switching device 140 via the signal connection 55. Upon receiving the fault signal Sst and / or the switching signal St, the switching device 140 then energizes or excites at least one solenoid valve 70 using the stored electrical energy of the storage device 120.
[0114] In particular, the inlet solenoid valve 71 (Fig. 3) is directly energized as "solenoid valve 70" and switched to the open position or held in the open position to create or maintain a connection between the compressed air reservoir 61 and the control input 81 of the relay valve 80, which then transmits the reservoir pressure present in the reservoir line 86 to the outlet 84 of the relay valve 80 and 2023P00190 DE
[0115] 16
[0116] so that it controls the spring brake cylinders of the spring brake, so that it remains released or releases.
[0117] This results in the electro-pneumatic parking brake (EPB) being actuated or held in the safe release state while the commercial vehicle is in motion. Preferably, this action is only performed while the vehicle is in motion. In other words, a first capacitor C1 of the storage device 120 is charged while the commercial vehicle is in motion and discharged when a power failure of the primary power supply unit 50 is detected. Active charging of the first capacitor C1 can occur, for example, when a predefined vehicle speed is exceeded (e.g., 5 km / h or 7 km / h).
[0118] The first capacitor C1 is automatically discharged, in particular, when the vehicle is detected as stationary, for example by the detection unit 110 and / or the electronic parking brake control 60, whereby it is checked whether the detected speed is approximately zero or below a predetermined speed limit. This ensures that malfunctions in the backup system 100 do not lead to the inlet solenoid valve 71 being energized and thus to an unintended release of the spring-applied parking brake.
[0119] In driving mode, the safe state is therefore the released state of the spring-applied brake. In contrast, when stationary, the safe state is the engaged state of the spring-applied brake.
[0120] In order to additionally establish the safe state of "tensioned spring brake" or a safe standstill when the commercial vehicle is stationary, a second capacitor C2 can be provided in the storage device 120.
[0121] The second capacitor C2 of the storage device 120 is preferably discharged in the driving state of the commercial vehicle detected or recognized by the detection unit 110 and / or by the electronic parking brake control 60, and charged when the commercial vehicle is stationary or detected. It can then be discharged, particularly in the event of a power failure of the primary power supply unit 50, in order to use the available backup electrical energy to directly switch the outlet solenoid valve 72 (Fig. 3) into the open position or to hold it in this position so that the spring-applied parking brake is engaged or remains engaged. 2023P00190 DE
[0122] 17
[0123] The backup system 100 therefore ensures that the electro-pneumatic parking brake (EPB) can be held in or switched to the safe driving state, even if a power failure occurs in the primary power supply unit 50 during driving. The backup system 100 therefore ensures this automatically in the event of a power failure, preferably without further interaction from the electronic parking brake control 60, which is unavailable during a power failure.
[0124] Fig. 2 shows a schematic flowchart of a preferred embodiment of a method for providing an electrical backup power supply for the electropneumatic parking brake of Fig. 1.
[0125] The procedure includes at least the following steps: In step S110, the driving condition and the failure of the primary power supply unit 50 are detected, for example by the detection unit 110.
[0126] In step S120, sufficient electrical energy is stored in a storage device 120 to switch or bring the electropneumatic parking brake EPB into the safe state or to keep it there.
[0127] In step S130, the electrical energy stored in the storage device 120 is supplied by the switching device 140 to the valve assembly 10 of the electropneumatic parking brake (EPB) when the failure of the primary power supply unit 50 and the driving state of the commercial vehicle are detected. The released state of the spring-applied parking brake is used as the safe state of the electropneumatic parking brake (EPB) in the driving state of the commercial vehicle. According to further embodiments, the exemplary capacitor of the storage device 120 is designed to provide a continuous power supply, particularly in the event of a power failure, so that no power drop occurs at the high-voltage node 75. This ensures the desired actuation of the at least one solenoid valve 70.
[0128] It is further clear that the backup system 100 is not only capable of switching a single solenoid valve 70, but that it can also be used to switch multiple solenoid valves, such as the inlet solenoid valve 71 and / or the outlet solenoid valve 72, as shown in Fig. 3. 2023P00190 DE
[0129] 18
[0130] The energy or capacitance of the exemplary capacitor 120 is sufficiently high to excite at least one solenoid valve 70 to one of its safe states. 2023P00190 DE
[0131] 19
[0132] REFERENCE MARK LIST
[0133] 10 Valve assembly
[0134] 30 Ventilation
[0135] 50 Primary power supply unit 55 Signal connection
[0136] 58 additional signal connections
[0137] 60 electronic parking brake control pC 61 compressed air supply
[0138] 65 Check valve
[0139] 70 Solenoid valve
[0140] 71 Inlet valve
[0141] 72 Exhaust valve
[0142] 76 Pressure sensor
[0143] 80 Relay valve
[0144] 81 Control input of the relay valve
[0145] 82 Vent or pressure sink
[0146] 84 Relay valve outlet
[0147] 85 Control pressure line
[0148] 86 Supply Management
[0149] 87 Spring storage connection
[0150] 89 Supply connection
[0151] 91 Preload spring
[0152] 93 Vehicle data bus
[0153] 95 external control
[0154] 100 Backup System2023P00190 EN
[0155] 20
[0156] 110 Recognition Unit
[0157] 120 storage device
[0158] 140 Switching device
[0159] EPB electropneumatic parking brake Sv speed signal
[0160] SST interference signal
[0161] Sz driving status signal
[0162] St switching signal
[0163] C1 first capacitor
[0164] C2 second capacitor
Claims
2023P00190 DE 21 PATENT CLAIMS 1. Electropneumatic parking brake (EPB) of a vehicle, comprising: a primary power supply unit (50), an electronic parking brake control (60) supplied with electrical energy by the primary power supply unit (50), a valve assembly (10) controlled by the electronic parking brake control (60) with several solenoid valves (70, 71, 72), a spring-applied brake that can be vented and de-vented by the valve assembly (10) and a backup system (100) configured to bring or switch the electropneumatic parking brake (EPB) into a safe state, characterized in that the backup system (100) comprises: a) Detection means (110, 60) configured at least to detect a fault or failure of the electronic parking brake control (60) and / or the primary power supply unit (50) and to generate a fault signal (Sst) when they detect the fault or failure, and b) a storage device (120) independent of the primary power supply unit (50) for storing sufficient electrical energy to bring or switch the electropneumatic parking brake (EPB) into the safe state, and c) a switching device (140) which is at least configured to supply the electrical energy to the storage device (120) of the valve device (10) by switching, when the switching device (140) c1 ) receives the interference signal (Sst) from the detection means (110, 60), or c2) receives a switching signal (St) from a control unit (95) that is independent of the parking brake control unit (60).
2. Electropneumatic parking brake (EPB) according to claim 1, characterized in that the valve assembly (10) comprises an inlet-outlet solenoid valve combination (71, 72) in particular with an inlet solenoid valve (71) and an outlet solenoid valve (72) as well as a pneumatically controlled relay valve (80), wherein the inlet-outlet valve combination (71, 72)2023P00190 DE 22 is intended to generate a control pressure at a pneumatic control input (81) of the relay valve (80).
3. Electropneumatic parking brake (EPB) according to claim 1 or 2, characterized in that the detection means (110, 60) are further configured to detect a driving state or a standstill of the vehicle and to generate a driving state signal (Sz) depending thereon.
4. Electropneumatic parking brake (EPB) according to claim 3, characterized in that the switching device (140) is further configured to supply at least one specific solenoid valve (70) of the valve assembly (10) with the electrical energy of the storage device (120), wherein the determination of the at least one solenoid valve (70) is dependent on the driving condition signal (Sz).
5. Electropneumatic parking brake (EPB) according to claim 3 or 4, characterized in that a) in the detected driving state, the safe state of the electropneumatic parking brake (EPB) is the released state of the spring-applied brake, and b) in the detected standstill, the safe state of the electropneumatic parking brake (EPB) is the applied state of the spring-applied brake.
6. Electropneumatic parking brake (EPB) according to claim 2 and one of claims 3 to 5, characterized in that the switching device (140) is configured to a) to switch the inlet-outlet solenoid valve combination (71, 72) to a ventilation position when the vehicle is detected as being in a driving state, and b) to switch the inlet-outlet solenoid valve combination (71, 72) to a venting position when the vehicle is detected as stationary. 2023P00190 DE 23 7. Electropneumatic parking brake (EPB) according to one of the preceding claims, characterized in that the storage device (120) of the backup system (100) comprises at least one capacitor.
8. Electropneumatic parking brake (EPB) according to one of the preceding claims, characterized in that the backup system (100) is a separate component or is integrated with other components of the electropneumatic parking brake (EPB) in a component.
9. A method for providing an electrical backup power supply for an electropneumatic parking brake (EPB) of a vehicle, comprising at least a primary power supply unit (50), an electronic parking brake control unit (60) supplied with electrical energy by the primary power supply unit (50), a valve assembly (10) controlled by the electronic parking brake control unit (60) with several solenoid valves (70, 71, 72), and a spring-applied parking brake that can be vented and released by the valve assembly (10) in order to bring or switch the electropneumatic parking brake (EPB) into a safe state by means of the electrical backup power supply, characterized in that the method comprises at least the following steps: a) Detecting (S110) a fault or failure of the electronic parking brake control (60) and / or the primary power supply unit (50) and generating a fault signal (Sst) upon detection of the fault or failure by detection means (60, 110); b) Storing (S120) sufficient electrical energy by means of a storage device (120) independent of the primary power supply unit (50) to perform bringing or switching the electropneumatic parking brake (EPB) into the safe state; c) Supply (S130) the electrical energy of the storage device (120) to the valve device (10) by switching a switching device (140) when the switching device (140) c1 ) receives the interference signal (Sst) from the detection means (110, 60), or c2) from a control independent of the parking brake control (60)2023P00190 DE 24 (95) receives a switching signal (St) for this purpose.
10. Method according to claim 9, characterized in that the detection means (110, 60) generate a driving condition signal (Sz) depending on whether they detect a driving condition or a standstill of the vehicle.
11. Method according to claim 10, characterized in that the switching device (140) supplies the electrical energy of the storage device (120) to at least one specific solenoid valve (70) of the valve assembly (10), wherein the determination of the at least one solenoid valve (70) is dependent on the driving condition signal (Sz).
12. Method according to one of claims 9 to 11, characterized in that a) in the detected driving state, the released state of the spring-applied parking brake is used as the safe state of the electropneumatic parking brake (EPB), and b) in the detected standstill, the engaged state of the spring-applied brake is used as the safe state of the electro-pneumatic parking brake (EPB).
13. Computer program comprising program code that causes the electropneumatic parking brake (EPB), in particular the backup system (100) according to any one of claims 1 to 8, to execute the method according to any one of claims 9 to 12 when the computer program is executed on a processor.