Redundant brake system

Abstract

In a brake system for a commercial vehicle, the commercial vehicle includes at least one steering shaft and at least one non-steering shaft, at least one pneumatic brake actuator associated with the steering shaft, at least one pneumatic brake actuator associated with the non-steering shaft, and an air handling unit. The brake system includes a redundant electro-pneumatic service brake system and an electro-pneumatic parking brake system, and the air handling unit includes two integrated pneumatic outputs configured to laterally independently actuate the pneumatic brake actuators on the steering shaft. At least one pneumatic brake actuator associated with the steering shaft is a pneumatic service brake actuator, and / or at least one pneumatic brake actuator associated with the non-steering shaft is a pneumatic spring brake actuator. The two integrated pneumatic outputs of the air handling unit include a two-channel pneumatic relay valve configured to pneumatically independently control a brake actuator on the steering shaft.

Description

Technical Field

[0001] This invention relates to a commercial vehicle braking system, including a redundant electro-pneumatic service brake system and an electro-pneumatic parking brake system. Background Technology

[0002] Autonomous operation of transport vehicles represents a new area of ​​innovation. More complex functions require specialized hardware infrastructure. Currently, commercial vehicle systems require a driver's presence and attention. However, future driver involvement in vehicle driving control tasks will decrease. Therefore, automated systems will take over more important driving functions, requiring higher levels of reliability and, consequently, different types of system redundancy. Furthermore, starting with a certain percentage of total production, for cost reasons, such vehicles will either be entirely without a driver's cab or only have an emergency cab. Accordingly, the driver interface (i.e., the brake pedal) can be simplified (e.g., eliminating pneumatic actuators) or even eliminated entirely.

[0003] The current technological situation presents the following problem: Commercial vehicles today use electro-pneumatic or drive-by-wire braking systems, where the electronic control components are implemented as single-loop controls. In the event of a malfunction in the control electronics, the driver can still control the pneumatic components of the braking system via foot, as a dual-loop pneumatic backup system remains available.

[0004] In highly automated vehicles, the driver is no longer in the control loop, or even inside the vehicle. The aforementioned braking system will be insufficient because there is no alternative to the driver controlling the brakes in the event of a failure in a single electronic control loop. Therefore, a certain degree of redundancy must be added to the braking system's control.

[0005] DE102008009043B3 discloses a redundant braking system for commercial vehicles. This system uses a parking brake integrated into the air supply unit as a redundant brake actuator. For axles without a spring-loaded parking brake chamber, the control output of the trailer control module is used as the pneumatic control input for the axle adjuster.

[0006] EP3626558B1 describes pneumatic booster valves that can control the spare port of the axle adjuster and optionally control the non-reverse input of the trailer control module. These booster valves can be controlled by a dedicated brake control ECU or an electronic parking brake unit that can receive electric braking demands, thereby eliminating the need for pneumatic devices in the cab.

[0007] EP3626559A1 relates to a redundant electro-pneumatic braking system in which the axle pressure adjusters are equipped with redundant digital communication lines to the auxiliary braking control ECU. Furthermore, these axle adjusters have redundant power supplies. This solution enables electrically controlled redundant circuits, thus eliminating the need for pneumatic devices in the cab, and the redundant braking system also provides full ESP functionality.

[0008] EP3415386A1 describes a redundant electro-pneumatic braking system in which the electronic parking brake system acts as a redundant brake by controlling the spring brake chamber on the rear axle, and the spare port of the front axle adjuster can also be controlled by the EPB (electronic parking brake) system by utilizing a reverse relay.

[0009] EP3626557B1 describes a redundant electro-pneumatic braking system in which the electronic parking brake system acts as a redundant brake by controlling a spring brake chamber on the rear axle, and the spare port of the front axle adjuster can also be controlled by the EPB system by utilizing a non-integrated electro-pneumatic booster valve.

[0010] EP3626557B1 also describes a multi-redundant braking system, which is a combination of redundant pressure regulators and redundant electronic parking brake systems. In this way, the vehicle has three independent electro-pneumatic braking systems capable of receiving electric braking demands. This eliminates the need for pneumatic devices in the cab, and allows the vehicle to continue operating autonomously even in the event of a single braking system failure.

[0011] EP2794368A1 discloses a redundant braking system for a commercial vehicle. This system uses a parking brake integrated into an air supply unit as a redundant brake actuator. For axles without a spring-loaded parking brake chamber, the air supply unit includes an additional electro-pneumatic adjuster to generate control pressure as the pneumatic control input to the axle adjuster.

[0012] EP2229302A1 illustrates a redundant braking system for a commercial vehicle. This system employs a pneumatic braking system as the main braking system and an electromechanical system as a redundant braking system. All axles are equipped with both types of brake actuators.

[0013] EP3938255A1 describes a redundant braking system in which the electronic parking brake can drive a backup port of the front axle adjuster via a reverse relay valve. Furthermore, a height selection valve, a reverse relay, or a pneumatic backup circuit for the brake pedal can all control the backup port of the front axle adjuster, thus retaining the pneumatic system in the cab.

[0014] EP3749558A1 discloses an electro-pneumatic redundant braking system employing a wheel adjuster with redundant pneumatic supply. To ensure circuit isolation, an additional service brake circuit separated by a protective valve is added, which can be used as a redundant pneumatic supply for the electro-pneumatic wheel module.

[0015] EP4116161A1 relates to a redundant braking system that employs an electronic parking brake system as the redundant braking system. An EPB module, which can be integrated into the air handling unit, includes valve assemblies with two reverse outputs and two non-reverse outputs to independently control the spare ports of the front and rear service brake regulators, the front and rear parking brake actuators, and the trailer control module, thereby achieving a redundant electro-pneumatic braking system. The EPB module (and the main brake control ECU) can receive braking requests directly from the foot brake module or the two automatic driving ECUs.

[0016] EP3452346A1 describes a redundant braking system in which the electronic parking brake can drive the rear axle parking brake chamber as a redundant braking circuit. Furthermore, a spare port of the front axle adjuster can be controlled via a pneumatic booster valve. By adding a bypass valve to this circuit, either the pneumatic output port of the foot brake module or the pneumatic output port of the booster valve can be connected to the spare port of the front axle adjuster. However, this method still retains a pneumatic device in the cab.

[0017] EP3600992A1 describes a redundant braking system in which the electronic parking brake can drive a backup port of the front axle adjuster via the pneumatic control output (yellow line) of the trailer control module. Furthermore, the backup port can be controlled by a height selection valve, a reverse relay, or a pneumatic backup circuit of the brake pedal, thus retaining the pneumatic system in the cab.

[0018] EP3600994A1 describes a redundant braking system in which an electronic parking brake is integrated into the trailer control module to achieve a redundant electro-pneumatic braking system for commercial vehicles.

[0019] EP3787942A1 discloses a redundant electro-pneumatic braking system in which the front and rear axle pressure regulators have redundant pneumatic supplies. Therefore, a third independent service brake pneumatic circuit must be added to ensure circuit isolation. The redundant axle module can receive braking demands directly from two automatic driving ECUs and optionally from a dedicated brake control ECU. A parking module, which can be integrated into the air handling unit, constitutes a redundant pair of main braking circuits. The EPB module has a reverse output to control the spring brake actuator and a non-reverse pneumatic output port as a spare port to optionally control the axle pressure regulator. The axle module can only control the service brake actuator. The parking brake actuator is controlled by a separate EPB module.

[0020] EP4001031A1 describes a braking system in which the electronic parking brake, as a redundant braking system, is equipped with dedicated yaw rate, acceleration, and wheel speed sensors to enable the redundant system to provide full ESP functionality. The parking brake module can independently control the front and rear spring brake actuators.

[0021] EP3787943A1 describes a redundant electro-pneumatic braking system in which all brake actuators are controlled by wheel pressure regulators with redundant pneumatic supplies. Therefore, a third independent service brake pneumatic circuit must be added to ensure circuit isolation. All wheel pressure regulators receive braking requests from two autonomous driving ECUs, but the wheel modules only control the service brake actuators. The parking brake actuator is controlled by a dedicated EPB module. Summary of the Invention

[0022] The purpose of this invention is to overcome the aforementioned problems in the prior art and provide a correspondingly improved braking system with appropriate redundancy, which can reliably control the braking system of commercial vehicles.

[0023] According to the invention, this objective is achieved by the commercial vehicle braking system as defined in claim 1. Advantageous embodiments of the invention are defined by dependent claims 2 to 15.

[0024] Accordingly, in the braking system according to the invention, the commercial vehicle includes at least one steering shaft and at least one non-steering shaft, at least one pneumatic brake actuator associated with the steering shaft, at least one pneumatic brake actuator associated with the non-steering shaft, and an air handling unit. The braking system is characterized by including a redundant electro-pneumatic service brake system and an electro-pneumatic parking brake system, wherein the air handling unit includes two integrated pneumatic outputs configured to independently actuate the pneumatic brake actuator on the steering shaft laterally.

[0025] This lateral independent actuation capability on the steering axis allows the brake actuators on the left and right sides of the axle (typically the front left and front right brake actuators) to be controlled independently. Accordingly, the front left brake actuator and the front right brake actuator can be controlled independently of each other by a redundant system.

[0026] The braking system according to the invention is preferably configured such that at least one pneumatic brake actuator associated with the steering shaft is a pneumatic service brake actuator, and / or at least one pneumatic brake actuator associated with a non-steering shaft is a pneumatic spring brake actuator.

[0027] The braking system according to the invention is preferably further configured such that: the two integrated pneumatic outputs of the air handling unit include dual-channel pneumatic relay valves, wherein the dual-channel pneumatic relay valves are configured to pneumatically independently control the brake actuator on the steering shaft.

[0028] Therefore, according to the present invention, in addition to the main electronic brake control unit or system (EBS), an auxiliary brake control unit, system, or function is also provided. To achieve a redundant electro-pneumatic braking system, the auxiliary brake control system can be integrated into the air handling system of the commercial vehicle to reduce system costs. The present invention describes a system in which the air handling unit includes two integrated pneumatic outputs, specifically dual-channel pneumatic relay valves, controlled by an integrated brake control device to independently actuate service brake actuators on the front axle or steering axle of the commercial vehicle. Wheel brakes on the rear axle or non-steering axle can be controlled by an integrated electronic parking brake module (EPB) via spring brake actuators.

[0029] According to one embodiment of the invention, the electronic brake control unit is also integrated into the air handling unit. Along with the electronic brake control unit, other functions, particularly vehicle dynamics control functions, can also be integrated into the air handling unit.

[0030] According to another embodiment of the invention, the braking system includes a parking brake module (PBM) integrated into the air handling unit. In an alternative or in-place embodiment, the braking system includes an electronic parking brake module (EPB) configured as a separate unit.

[0031] In other embodiments of the invention, the braking system is configured such that the air handling unit receives electronic parking brake demand signals and / or electronic service brake demand signals from an external source.

[0032] In other embodiments of the invention, the braking system is configured such that the air handling unit receives an electronic parking brake demand signal from the manual control unit and / or an electronic service brake demand signal from the foot brake sensor, to respectively meet the driver's braking needs.

[0033] According to other, alternative, or optional embodiments of the invention, the braking system includes a 3 / 2 solenoid valve and / or a pneumatic height selector valve, which are respectively configured to achieve loop separation of the main pneumatic circuit and the redundant pneumatic circuit before the brake actuator mounted on the steering shaft.

[0034] In other embodiments of the invention, the braking system is characterized in that the air handling unit is configured to control the trailer braking system using a digital trailer CAN (ISO11992) communication interface and / or a digital trailer Ethernet communication interface. Attached Figure Description

[0035] The various embodiments of the present invention will now be described in detail with reference to the accompanying drawings, in order to further illustrate the details and advantages of the present invention.

[0036] Figure 1 A first embodiment of an electro-pneumatic braking system with redundant braking control integrated into an air handling module according to the present invention is shown.

[0037] Figure 2 Another embodiment of the electro-pneumatic braking system according to the present invention, having redundant braking control integrated into the air handling module, is shown.

[0038] Figure 3 Another embodiment of an electro-pneumatic braking system with redundant braking control integrated into an air handling module according to the present invention is shown. Detailed Implementation

[0039] Figure 1 The braking system architecture of a commercial vehicle is illustrated. As shown, the vehicle includes a front axle F and a rear axle R. It should be understood that any other number of front and / or rear axles may be provided in the vehicle. Any of these axles can be a steering axle or a non-steering axle. For the purposes of this disclosure, it is assumed that the front axle F is a steering axle and the rear axle R is a non-steering axle.

[0040] The braking system includes a main electronic brake control unit or electronic braking system (EBS) 3, which constitutes and / or is part of a first (electric / electronic) braking circuit. The main EBS unit is powered by battery 1. The EBS unit electronically controls the front axle module (front axle pressure regulator) 9 and the rear axle module (rear axle pressure regulator) 10. The EBS unit also electronically controls the trailer control module 8. Furthermore, the EBS unit electronically controls the pressure control valve 11 on the front axle F. The front axle wheel brakes are actuated by a service brake chamber / actuator 12 pneumatically actuated by the pressure control valve 11. The rear axle wheel brakes employ a spring brake combination cylinder / actuator 13 pneumatically actuated by the rear axle pressure regulator 10.

[0041] When the braking system is intact, the service brakes are controlled by the EBS electronic device 3, which is the main unit.

[0042] To achieve a redundant electro-pneumatic braking system, an auxiliary braking control unit or function is provided, which can be integrated into the air handling system 4 of the commercial vehicle. The air handling unit 4 is powered by the battery 2 and constitutes and / or is part of a second (electrical / electronic) braking circuit. As shown, the air handling unit 4 supplies compressed air to relevant components of the braking system via pneumatic supply lines, among other things. Here, the air handling unit 4 includes two integrated pneumatic outputs that laterally and independently actuate pneumatic brake actuators (e.g., service brake actuator 12) on the steering shaft (e.g., the front axle F). Accordingly, the left front brake actuator 12 and the right front brake actuator 12 can be independently controlled by the redundant system.

[0043] Accordingly, Figure 1An electro-pneumatic braking system with redundant braking control integrated into the air handling module 4 is shown, which is capable of independently actuating the service brake chamber / actuator 12 mounted on the steering shaft F.

[0044] In this system, the air handling unit 4 specifically includes a dual-channel pneumatic relay valve, which is controlled by the electronic brake control unit integrated into the air handling unit 4 to independently actuate the service brake actuator 12 on the steering axle F. The dual-channel pneumatic relay valve can independently control the two pneumatic brake actuators.

[0045] Along with the electronic brake control unit, other functions (such as vehicle dynamics control) may optionally be integrated into the air handling unit 4.

[0046] The wheel brakes of the non-steering axle (e.g., the rear axle R) can be controlled by the electric / electronic parking brake module (EPB / PBM), which is also integrated into the air handling unit 4, via spring brake actuators (see [link]). Figure 1 ).

[0047] Considering the redundant electro-pneumatic braking system, in the event of a failure of the main electronic brake control unit (EBS) 3 or its power supply unit 1, the braking control function is taken over by the air handling unit 4 (i.e., the aforementioned auxiliary brake control unit or function). Here, the axle R equipped with the spring brake chamber / actuator 13 is actuated by the parking brake control, while the brake actuators 12 of the other axles F are pneumatically and independently controlled by the integrated relay valve.

[0048] If any malfunction occurs in the air handling unit 4 or its power supply unit 2, the main electronic brake control unit (EBS) 3 will control the braking system as described above under normal and intact conditions.

[0049] like Figure 1 As further shown, a so-called 3 / 2 solenoid valve 14 is provided upstream of the service brake actuator 12 associated with the steering shaft (i.e., the front axle F in this case). This valve 14 is used to achieve circuit separation between the main pneumatic circuit and the redundant pneumatic circuit. Accordingly, as Figure 1 As shown, valve 14 is controlled by a pneumatic control circuit from air preparation system 4 and / or from front axle pressure regulator 9. Valve 14 itself pneumatically controls pressure control valve 11.

[0050] Typically, a 3 / 2 solenoid valve is a key component in a pneumatic system, used to operate pneumatic actuators because it controls the flow and pressure of compressed gas or liquid. It opens or closes the air circuit based on an electrical signal. A 3 / 2 passage valve usually has three ports and two positions, and can be operated by a solenoid valve (e.g., pneumatic or electric).

[0051] As Figure 1As shown in the diagram, an alternative to the 3 / 2 solenoid valve 14 is that the circuit separation of the main pneumatic line and the redundant pneumatic line can be achieved by a so-called pneumatic height selection valve 14, which is located upstream of the service brake actuator 12 associated with the steering shaft (i.e., the front axle F in this case). Figure 2 As shown. The pneumatic height selection valve has two pneumatic inputs and one pneumatic output. The input port with the higher air pressure level (compared to the other input port) will be connected to the output port. Accordingly, Figure 2 An electro-pneumatic braking system with redundant braking control integrated into the air handling module 4 is shown, wherein the circuit separation of the main pneumatic line and the redundant pneumatic line is achieved by a pneumatic height selection valve 14.

[0052] Attached Figure ( Figures 1 to 3 The various electrical and pneumatic circuits required to realize the functions and connections of the braking system are schematically illustrated using various types of lines (solid lines, dashed lines, dotted lines, dotted-dashed lines, etc.). These include, for example, analog power supply and signal lines and digital electrical signal lines for the first, second, and third (electrical / electronic) braking circuits, respectively, and pneumatic supply lines and pneumatic control lines for the service brake and parking brake, respectively. Therefore, other features and functions of the braking system that are not explicitly discussed in this disclosure but are part of this disclosure are clearly apparent from the accompanying drawings.

[0053] Unless otherwise stated or shown in the accompanying drawings, the foregoing regarding Figure 1 The explanation, after necessary modifications, is basically applicable. Figure 2 and Figure 3 The same reference numerals are used to denote the same or corresponding features.

[0054] In the above Figure 1 and Figure 2 In some embodiments, the auxiliary braking control unit or function, including the electric / electronic parking brake module (EPB / PBM), is integrated into the air handling system 4 of the commercial vehicle. Figure 3 In the alternative embodiment shown, the electric / electronic parking brake unit (EPB) 17 is a separate unit not integrated into the air treatment module 4. This EPB unit is powered by a separate battery 18 and forms part of a third (electric / electronic) braking circuit. Battery 18 is independent of batteries 1 and 2. The EPB unit pneumatically controls the spring brake actuator 13 associated with the vehicle's rear axle R and the trailer control module 8.

[0055] therefore, Figure 3 An electro-pneumatic braking system with redundant braking control integrated into the air handling module 4 is shown, including a separate electric / electronic parking brake module (EPB) 17.

[0056] like Figures 1 to 3As shown, the air handling unit 4, which includes integrated brake control, can receive electric / electronic driving and / or parking brake demand signals from an external source 16. Figure 3 In the illustrated embodiment, a separate electric / electronic parking brake module (EPB) 17 can receive electric / electronic braking demand signals from an external source 19. The main electronic brake control system (EBS) 3 can receive electric / electronic braking demand signals from an external source 15. These braking demand signals can be generated by external electrical / electronic components, for example, for highly automated / autonomous driving (HAD).

[0057] Furthermore, the air handling unit 4, which includes integrated brake control, can receive electric / electronic parking brake demand signals from the manual control unit (HCU) 6 for parking brake, and / or from the foot brake sensor (FBS) 5 for electric / electronic service brake demand signals, to respectively meet the braking demands generated by the vehicle driver. Figure 3 In the illustrated embodiment, the independent electric / electronic parking brake module (EPB) 17 can receive an electric / electronic braking demand signal from the manual control unit 6 used for parking braking.

[0058] In addition to the functions mentioned above, the air handling unit 4 can also control the trailer braking system 7 using the digital trailer CAN (ISO11992) communication interface / protocol or the digital trailer Ethernet communication interface.

[0059] List of reference numerals

[0060] 1 power supply unit / battery

[0061] 2 power supply units / batteries

[0062] 3. Main Electronic Brake Control Unit / Brake System (EBS)

[0063] 4. Air handling unit / system

[0064] 5. Foot Brake Sensor (FBS)

[0065] 6. Manual Control Unit (HCU)

[0066] 7. Communication with the trailer braking system

[0067] 8 Trailer Control Module

[0068] 9. Front axle pressure regulator / front axle module

[0069] 10 Rear Axle Pressure Regulator / Rear Axle Module

[0070] 11. Pressure Control Module / Valve (PCV)

[0071] 12 Service brake chamber / actuator

[0072] 13 Spring Brake Combination Cylinder / Actuator

[0073] 14 3 / 2 Solenoid Valve / Pneumatic Height Selector Valve

[0074] 15 External Sources of Electric / Electronic Braking Demand Signals

[0075] 16 External sources of electric / electronic driving and / or parking brake demand signals

[0076] 17 Independent Electric / Electronic Parking Brake Units / Modules (EPB)

[0077] 18 Power supply unit / battery

[0078] 19 External Sources of Electric / Electronic Braking Demand Signals

[0079] F Vehicle front axle

[0080] R Vehicle rear axle

Claims

1. A brake system for a commercial vehicle, wherein, The commercial vehicle comprises: - at least one steering axle (F) and at least one non-steering axle (R), - at least one pneumatic brake actuator (12) associated with the steering axle (F), - at least one pneumatic brake actuator (13) associated with the non-steering axle (R), and - an air treatment unit (4), characterized in that the brake system comprises a redundant electro-pneumatic service brake system and an electro-pneumatic parking brake system, wherein the air treatment unit (4) comprises two integrated pneumatic outputs configured to be able to independently actuate the pneumatic brake actuators (12) on the steering axle (F) laterally.

2. The brake system of claim 1, wherein, The at least one pneumatic brake actuator (12) associated with the steering axle (F) is a pneumatic service brake actuator (12), and / or the at least one pneumatic brake actuator (13) associated with the non-steering axle (R) is a pneumatic spring brake actuator (13).

3. The brake system according to claim 1 or 2, characterized in that, The two integrated pneumatic outputs of the air treatment unit (4) comprise a two-channel pneumatic relay valve, wherein the two-channel pneumatic relay valve is configured to be able to independently pneumatically control the brake actuators (12) on the steering axle (F).

4. The brake system according to any one of the preceding claims, characterized in that, An electronic brake control unit is integrated into the air treatment unit (4).

5. The brake system of claim 4, wherein, Together with the electronic brake control unit, other functions, in particular vehicle dynamics control functions, are integrated into the air treatment unit (4).

6. The brake system according to any one of the preceding claims, characterized in that, The brake system comprises a parking brake module PBM integrated into the air treatment unit (4).

7. The brake system according to any of the preceding claims, characterized in that The brake system comprises an electronic parking brake module EPB (17) configured as a separate unit.

8. The brake system according to any of the preceding claims, characterized in that The brake system is configured such that the air treatment unit (4) receives an electronic parking brake demand signal from an external source (16).

9. The brake system according to any of the preceding claims, characterized in that The brake system is configured such that the air treatment unit (4) receives an electronic service brake demand signal from a foot brake sensor (5) to meet the driver's brake demand.

10. The brake system according to any one of the preceding claims, characterized in that, The brake system is configured such that the air treatment unit (4) receives an electronic service brake demand signal from an external source (16).

11. The brake system according to any of the preceding claims, characterized in that The brake system comprises a 3 / 2 solenoid valve (14) configured to enable a loop separation of a main pneumatic line and a redundant pneumatic line upstream of the brake actuators (12) mounted on the steering axle (F).

12. The brake system according to any of the preceding claims, characterized in that The brake system comprises a pneumatic high selection valve (14) configured to enable a loop separation of a main pneumatic line and a redundant pneumatic line upstream of the brake actuators (12) mounted on the steering axle (F).

13. The brake system according to any of the preceding claims, characterized in that The air treatment unit (4) is configured to be able to control a trailer brake system (7) using a digital trailer CAN (ISO 11992) communication interface.

14. The brake system of any of the preceding claims, characterized in that The air treatment unit (4) is configured to be able to control a trailer brake system (7) using a digital trailer Ethernet communication interface.

15. The brake system of any of the preceding claims, characterized in that ​

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