Parking brake valve assembly with monostable and fault-tolerant design

Abstract

The invention relates to a parking brake valve assembly (1) for an electronically controllable pneumatic brake system (210) of a commercial vehicle (202), the parking brake valve assembly comprising: a first compressed air path (2) receiving a reserve pressure (pV, pV1, pV2), which has a first monostable valve unit (6) for providing a first parking brake pressure (pF1); a second compressed air path (4) receiving a reserve pressure (pV, pV1, pV2), which has a second monostable valve unit (8) for providing a second parking brake pressure (pF2); and a first shuttle valve (10), The invention comprises a first shuttle valve interface (10.1) connected to a first compressed air path (2) and receiving a first parking brake pressure (pF1), a second shuttle valve interface (10.2) connected to a second compressed air path (4) and receiving a second parking brake pressure (pF2), and a third shuttle valve interface (10.3) connectable to a spring-accumulated brake cylinder (220a, 220b, 220c, 220d), wherein the first shuttle valve (10) always adjusts the higher of the first parking brake pressure (pF1) and the second parking brake pressure (pF2) at the third shuttle valve interface (10.3). The invention also relates to a brake system (202) and a commercial vehicle (210).

Description

Technical Field

[0001] The invention relates to a parking brake valve assembly for an electronically controllable pneumatic brake system of a vehicle, in particular a commercial vehicle. The invention also relates to an electronically controllable pneumatic brake system and a vehicle. Background Art

[0002] In vehicles, especially commercial vehicles, with a pneumatic brake system, especially in the form of an electronic brake system (EBS) or an anti-lock brake system (ABS), a control unit (ECU) can actuate an electropneumatic valve, for example an electropneumatic switching valve connected upstream of a relay valve, in order to regulate a brake pressure, which is then pneumatically transmitted to the brake cylinders of the service brakes of the brake system as a function of the requested target deceleration of the vehicle. Modules that integrate such units are often referred to as axle modulators.

[0003] In a braking system for a vehicle train with a tractor and trailer, the braking system has a trailer control unit, also called a trailer control valve (TCV), which is configured to pneumatically control a predefined vehicle target deceleration of the tractor via interfaces, also called "yellow" and "red" couplings, namely a trailer brake pressure interface and a trailer supply pressure interface. The trailer is supplied with supply pressure from a reservoir provided for this purpose in the tractor via the trailer supply pressure interface, while the corresponding brake pressure is controlled via the trailer brake pressure interface.

[0004] Braking systems of the type mentioned above have a parking brake unit as a further component or module, also known as an electropneumatic handbrake (EPH). Such parking brake units are usually operated with a so-called spring accumulator, i.e. a brake device which brakes one or more axles of the vehicle based on spring force. In the vented state, the brake is released, in the exhausted state, the brake is applied. In the unpressurized state, the respective vehicle is braked. In order to activate the parking brake unit, an electrical switch is usually provided in the cab of the tractor, via which a corresponding signal can be output to an electronic control unit, which then switches one or more electropneumatic valves so that the spring accumulator is either exhausted or ventilated.

[0005] In order to park the motor vehicle train, the parking brake unit (i.e. the electropneumatic handbrake) can also be used as an additional brake in special cases. That is, in addition to the normal service brake, the spring accumulator is at least partially exhausted so that it can be used additionally or alternatively for braking. For example, in the case of pure auxiliary braking, braking is only performed by the spring accumulator in the tractor and the service brake in the trailer. In the case of pure auxiliary braking, the service brake in the tractor is not confirmed. Alternatively, a redundant mode can also be implemented, for example, in the event of failure of the rear axle circuit, the spring accumulator can be used instead of the service brake. The front axle can still be braked with the service brake, and the trailer can also be braked with the service brake.

[0006] The parking brake valve assembly of the type described above and related to the present invention is used in such parking brake units or as such parking brake units when the parking brake valve assembly is integrated into a module. Usually, such parking brake valve assemblies work together with a relay valve to increase the pilot pressure volume provided by the pilot control unit. A typical parking brake valve assembly in the form of a parking brake module is disclosed in the applicant's patent document DE 10 2012 000435 A1. The module disclosed in the document has a relay valve, which supplies the pilot control pressure via a pilot control unit consisting of a 2 / 3-way valve and a 2 / 2-way valve. The relay valve increases the pilot control pressure volume and provides it to a spring accumulator interface, where one or more spring accumulator brake cylinders can be connected. A similar module is also disclosed in the applicant's patent document EP 2254779 B1. Another example of a similar type is disclosed in the patent document DE 10 2007 047 691 A1.

[0007] In addition, other systems are also known, such as systems including a bistable valve in the pilot control unit. Examples of this are disclosed in patent documents DE 10 2017 002 715 A1 or DE 10 2017 002 714 A1 of the applicant.

[0008] There is also an integrated approach of integrating the parking brake unit with the trailer control valve. Such a system is described in patent document DE 10 2017 002 953, for example.

[0009] In modern electronically controllable pneumatic brake systems, in particular for autonomous commercial vehicles, it is important to provide measures for safely decelerating the commercial vehicle in the event of a brake system failure. This involves the use of fully redundant brake systems, partially redundant brake systems or simply different levels in the brake system, so that in the event of a failure of the first level, the brake system can continue to operate at least to a limited extent in the second level.

[0010] However, if a double fault occurs, for example involving both the primary and redundant braking systems, there is a risk that the commercial vehicle can no longer brake in a controlled manner. For this situation, it is necessary to provide a system that allows the vehicle to be decelerated safely.

[0011] For example, patent document DE 10 2014 013 756 B3 discloses a system specifically for high residual availability. The document discloses a vehicle electrical equipment with an at least partially electric brake and steering device, which includes an electric or electromechanical steering device connected to a steering transmission mechanism, and includes an electronic steering control device and an electric steering regulator and a service brake device. As a service brake device, patent document DE 10 2014 013 756 B3 proposes an electropneumatic service brake device, including an electropneumatic service brake valve device, an electronic brake control device, an electropneumatic modulator and a pneumatic wheel brake actuator, wherein the electronic brake control device electrically controls the electropneumatic modulator to generate a pneumatic brake pressure or a brake control pressure for the pneumatic wheel brake actuator for each wheel, each axle or each vehicle side. The electropneumatic service brake valve device has a service brake operating mechanism and also has an electric brake value transmitter in the electrical channel of the electric service brake circuit that can be operated by the service brake operating mechanism. An electronic evaluation device is also provided which receives the actuation signal and feeds a brake request signal to an electronic brake control device in dependence on the actuation signal, and further comprises at least one pneumatic channel in at least one pneumatic service brake circuit, wherein by actuating the service brake actuation mechanism based on the driver's brake request, at least one control piston of the service brake valve device is loaded with a first actuation force and the control piston allows, in response thereto, the generation of a pneumatic brake pressure or brake control pressure for the pneumatic wheel brake actuator. The electronic evaluation device of the electropneumatic service brake valve device also comprises an electronic control device for generating a second actuation force independent of the driver's brake request, which second actuation force acts on the control piston in the same direction or opposite direction relative to the first actuation force when there is a brake request independent of the driver's request. The electropneumatic service brake device is supplied with electrical energy by a power source which is independent of a second power source which supplies electrical energy to the electropneumatic service brake valve device. This ensures that at least one of the two systems is always operational as far as possible. The electric or electropneumatic steering device is supplied with energy by the second power source. This makes it possible to achieve a high residual availability. However, the system is complex and cannot be easily implemented in every commercial vehicle.

[0012] Patent document DE 10 2016 005 318 A1 discloses a system for providing redundancy of an electro-pneumatic control. The system disclosed in the document uses a bypass valve to transfer a control pressure according to the failure of a subsystem, so as to supply the circuit that fails electrically at least pneumatically. This also increases the residual availability. Patent documents DE 10 2016 010462 A1 and DE 10 2016 010 464 A1 disclose similar systems.

[0013] Furthermore, patent document DE 10 2016 010 463 A1 discloses a system and a method in which, if a failure or defect is detected in the electronic control of the wheel brakes of the brake system, a pilot control valve is electrically controlled by a redundant signal. The system thus attempts to prevent wheel locking.

[0014] Patent documents DE 10 2017 002 716, DE 10 2017 002 718, DE 10 2017 002 719 and DE 10 2017 002 721 disclose systems that generate redundancy pneumatically. Here, various regulated brake pressures (e.g. front axle brake pressure, rear axle brake pressure or trailer brake pressure) are used to provide redundant pressure for these failed systems (e.g. front axle brake circuit, rear axle brake circuit, parking brake circuit or trailer brake circuit). This creates a lower pneumatic redundancy level, thereby also achieving high residual availability.

[0015] Furthermore, there are systems which include a trailer, see for example patent document DE 10 2016 010 461 A1. Summary of the invention

[0016] Against this background, the object of the present invention is to provide a parking brake valve assembly of the aforementioned type which is improved in terms of safety, in particular to provide a parking brake valve assembly which does not maintain the released state in the event of a serious double fault, but provides a solution which allows a controlled braking of the vehicle. In this way, the vehicle should be able to be brought into a safe state in a controlled manner and prevented from rolling away, even in the event of a fault, such as a power failure, in which electrical braking is no longer possible.

[0017] The present invention solves the technical problem in the aforementioned type of parking brake valve assembly in the following manner: a first compressed air path for receiving a first or second reserve pressure is provided, which has a first monostable valve unit for providing a first parking brake pressure; a second compressed air path for receiving the first or second reserve pressure is provided, which has a second monostable valve unit for providing a second parking brake pressure; a first shuttle valve is also provided, which has a first shuttle valve interface connected to the first compressed air path and receiving the first parking brake pressure, a second shuttle valve interface connected to the second compressed air path and receiving the second parking brake pressure, and a third shuttle valve interface connected to or connectable to a spring-energy storage brake cylinder, wherein the first shuttle valve always regulates the higher of the first parking brake pressure and the second parking brake pressure at the third shuttle valve interface.

[0018] According to the invention, the higher of the first parking brake pressure and the second parking brake pressure is always regulated at the third shuttle valve interface which is directly or indirectly connected to one or more spring-accumulator brake cylinders or can be directly or indirectly connected thereto. Only this pressure, i.e. the higher of the two parking brake pressures, is used to ventilate the correspondingly connected spring-accumulator brake cylinder. One or more spring-accumulator brake cylinders can be directly connected to the third shuttle valve interface, i.e. the volume pressure for ventilating at least one spring-accumulator brake cylinder is directly regulated at the third shuttle valve interface. On the other hand, it is also conceivable and preferred that a relay valve is first connected to the third shuttle valve interface, which relay valve then increases the volume of the pressure received from the third shuttle valve interface and provides the increased volume pressure to one or more spring-accumulator brake cylinders. The core idea is that the shuttle valve is driven by two independent compressed air paths designed as monostable. Each of the first compressed air path and the second compressed air path is monostable, i.e., returns to a switching state in the absence of current, and is not designed as bistable as is conventional in the prior art, i.e., the switched state is maintained even in the absence of current. However, as long as one of the first compressed air path and the second compressed air path provides parking brake pressure, i.e., the first parking brake pressure or the second parking brake pressure, the spring-accumulator brake cylinder remains ventilated and thus released. Only when both compressed air paths do not provide any parking brake pressure will the spring-accumulator brake cylinder be exhausted and thus compressed.

[0019] This arrangement provides, for example, a way to couple the first compressed air path to the first brake circuit and the second compressed air path to the second brake circuit, so that, for example, the spring-accumulator brake cylinder is only switched in the event of a failure of both brake circuits. This improves the safety of the vehicle equipped with the parking brake valve assembly. In the event of a severe double fault, in which both the first brake circuit and the second brake circuit fail, i.e. the first compressed air path and the second compressed air path no longer provide any parking brake pressure, the vehicle equipped with the parking brake valve assembly brakes automatically. It may also be preferred to couple the first compressed air path to the operating stage of the brake system and the second compressed air path to the redundant stage. The spring-accumulator brake cylinder is only switched in the event of a failure of both the operating stage and the redundant stage.

[0020] According to a first preferred embodiment, the first monostable valve unit is switched by a first electronic control unit and the second monostable valve unit is switched by a second electronic control unit. The first electronic control unit and the second electronic control unit are preferably independent of each other. For example, the first electronic control unit is the control unit of the central module and the second electronic control unit is the control unit of an axle modulator, such as a front axle modulator or a rear axle modulator. It is also conceivable that the second electronic control unit is the control unit of an integrated parking brake module. Other control units may also be used. For example, the first electronic control unit is the electronic control unit of the front axle brake circuit and the second electronic control unit is the electronic control unit of the rear axle brake circuit. It is also conceivable and preferred that the first electronic control unit is the operating level and the second electronic control unit is the redundant level.

[0021] It is furthermore preferably provided that the first monostable valve unit is supplied with power by a first voltage source and the second monostable valve unit is supplied with power by a second voltage source. With regard to the first voltage source and the second voltage source, the same applies as described with regard to the first electronic control unit and the second electronic control unit. It is preferred in this regard that the first voltage source is, for example, assigned to the front axle brake circuit and the second voltage source is assigned to the rear axle brake circuit. The first voltage source and the second voltage source are preferably independent of one another. It is also conceivable that the first voltage source is assigned to the operating stage and the second voltage source is assigned to the redundancy stage.

[0022] According to another preferred embodiment, the first monostable valve unit has a first switching valve and a second switching valve, which are connected to each other in a pressure-conducting manner so that the first parking brake pressure is regulated only when the first switching valve and the second switching valve are energized, and the second monostable valve unit has a third switching valve and a fourth switching valve, which are connected to each other in a pressure-conducting manner so that the second parking brake pressure is regulated only when the third switching valve and the fourth switching valve are energized. In this way, safety can be further improved. A failure of one of the first switching valve and the second switching valve or one of the third switching valve and the fourth switching valve is sufficient to cause one of the first compressed air path and the second compressed air path to become pressure-free. At the same time, both valves must be energized to regulate the corresponding parking brake pressure. This ensures that the spring accumulator pressure will not be regulated when one of the valves is not switched or the valve is switched incorrectly, but in fact the spring accumulator pressure will be regulated only when the corresponding switching signal is provided to the first switching valve and the second switching valve or the third switching valve and the fourth switching valve, thereby ensuring that the corresponding superior control unit and / or voltage source works normally.

[0023] It is preferably proposed here that the first switching valve is configured as a first 2-position 3-way valve, the second switching valve is configured as a second 2-position 3-way valve, the third switching valve is configured as a third 2-position 3-way valve, and the fourth switching valve is configured as a fourth 2-position 3-way valve, wherein the first 2-position 3-way valve and the second 2-position 3-way valve are pneumatically connected in series, and the third 2-position 3-way valve and the fourth 2-position 3-way valve are pneumatically connected in series. This achieves a particularly simple wiring method, which is configured as a monostable state and results in that the valves in series must always be switched in order to regulate the first parking brake pressure or the second parking brake pressure.

[0024] It is also preferred that the first switching valve has a first switching valve interface for receiving a reserve pressure, a second switching valve interface connected to the second switching valve interface, and a third switching valve interface connected to the exhaust end, wherein, in the first switching position where power is supplied, the first switching valve interface is connected to the second switching valve interface, and in the second switching position where there is no current, the second switching valve interface is connected to the third switching valve interface. This is also preferably applicable to the second switching valve, the third switching valve, and the fourth switching valve. Therefore, it is preferably proposed that the second switching valve has a fourth switching valve interface connected to the second switching valve interface, a fifth switching valve interface connected to the first shuttle valve interface, and a sixth switching valve interface connected to one or the exhaust end, wherein, in the first switching position where power is supplied, the fourth switching valve interface is connected to the fifth switching valve interface, and in the second switching position where there is no current, the fifth switching valve interface is connected to the sixth switching valve interface. Similarly, it is also preferred to provide the following arrangement for the second compressed air path. The third switching valve has a seventh switching valve interface for receiving the reserve pressure, an eighth switching valve interface connected to the fourth switching valve interface, and a ninth switching valve interface connected to one or the exhaust end, wherein in the first switching position with power, the seventh switching valve interface is connected to the eighth switching valve interface, and in the second switching position without power, the eighth switching valve interface is connected to the ninth switching valve interface. Finally, the fourth switching valve preferably also has a tenth switching valve interface connected to the eighth switching valve, an eleventh switching valve interface connected to the second shuttle valve interface, and a twelfth switching valve interface connected to one or the exhaust end, wherein in the first switching position with power, the tenth switching valve interface is connected to the eleventh switching valve interface, and in the second switching position without power, the eleventh switching valve interface is connected to the twelfth switching valve interface.

[0025] In another preferred embodiment, it is proposed that the first compressed air path is connected to an exhaust valve, in particular a single exhaust valve, for exhausting the first shuttle valve connection and the second compressed air path is connected to exhausting the second shuttle valve connection. Through the exhaust valve, the switching valve, the first shuttle valve or the second shuttle valve connection can be exhausted individually to exhaust the spring-accumulator brake cylinder connected to the third shuttle valve connection and thus brake the vehicle. Therefore, preferably, a single exhaust valve is provided for both the first compressed air path and the second compressed air path. The exhaust valve is preferably configured so that it has a nonlinear exhaust characteristic curve. Preferably, the exhaust valve allows the first shuttle valve connection or the second shuttle valve connection and thus the third shuttle valve connection to be exhausted from a release pressure corresponding to the parking brake pressure, which is sufficient to release the spring-accumulator brake cylinder connected to the third shuttle valve connection, with a first gradient to a partial brake pressure, and allows the first shuttle valve connection or the second shuttle valve connection to be exhausted from the partial brake pressure to the full brake pressure with a second gradient, wherein the first gradient is greater than the second gradient. If the spring-accumulator brake cylinders are exhausted in this way through the exhaust valve, they are not immediately directly connected, but present a nonlinear exhaust characteristic curve. The nonlinear exhaust characteristic curve is configured such that the first shuttle valve interface or the second shuttle valve interface or the third shuttle valve interface is first exhausted from the release pressure to the partial brake pressure with a first gradient. The release pressure is preferably the minimum pressure required to completely release the spring-accumulator brake cylinder connected to the third shuttle valve interface. According to the present embodiment, the exhaust from this release pressure to the partial brake pressure is very fast. The partial brake pressure is preferably designed so that the vehicle is only partially braked but not completely braked. Therefore, braking should have occurred, but the axle will not be locked immediately. From the partial brake pressure that performs partial braking until the full brake pressure at which the spring-accumulator brake cylinder is completely exhausted in a corresponding manner and thus fully compressed, exhaust is performed with a second gradient. The second gradient is smaller than the first gradient, so that braking from the partial brake pressure to the full brake pressure occurs more slowly. In this way, a safe deceleration of the vehicle can be provided and the risk of immediate locking of the axle can be overcome. Here, the first gradient and the second gradient do not need to be constant. On the contrary, the first gradient and the second gradient can also define a nonlinear exhaust characteristic curve. Specifically, it is preferred that the average gradient when exhausting the shuttle valve from the release pressure to the partial brake pressure is greater than the average gradient when exhausting the shuttle valve from the partial brake pressure to the full brake pressure. Preferably, the first gradient and the second gradient are constant. The first gradient is preferably equal to 1.2 to 100 times, preferably 1.2 to 20 times, the second gradient.

[0026] In a particularly preferred embodiment, the exhaust valve has a pressure limiter and a throttle, which is arranged in parallel with the pressure limiter and allows overflow of the pressure limiter. It is also possible to provide two or more pressure limiters and two or more throttles for each pressure limiter. By providing a pressure limiter and a throttle that allows overflow of the pressure limiter, a nonlinear exhaust characteristic curve can be provided in a simple manner. For example, exhaust of the shuttle valve from release pressure to partial brake pressure is mainly achieved by the pressure limiter, while exhaust of the shuttle valve from partial brake pressure to full brake pressure is mainly achieved by the throttle.

[0027] According to another preferred embodiment, the parking brake valve assembly also has a trailer valve unit for providing a trailer pressure. The trailer pressure can be a trailer parking brake pressure or a trailer reserve pressure, in particular when the parking brake valve assembly is used in an American brake system variant. The trailer valve unit can be used to actuate not only the spring-accumulated brake cylinder of the tractor but also the trailer at the same time. In the case that the parking brake valve assembly according to the embodiment described here is to be connected to the spring-accumulated brake cylinder of the vehicle, the spring-accumulated brake cylinder for the trailer can also be connected via the trailer valve unit. In this case, the trailer is also braked.

[0028] Preferably, the trailer valve unit is connected to the first compressed air path and the second compressed air path. In this way, it can obtain the same function as the shuttle valve.

[0029] It is also preferred that the trailer valve unit receives the first trailer pilot pressure from the first compressed air path and the second trailer pilot pressure from the second compressed air path and always regulates the higher of the two as the trailer pressure. The pressure regulated via the first compressed air path and the second compressed air path is used not only to actuate the spring-loaded brake cylinder of the tractor but also to brake the trailer via the trailer valve unit.

[0030] In this regard, it is preferred that the trailer valve unit has a first monostable trailer switching valve connected to the first compressed air path and a second monostable trailer switching valve connected to the second compressed air path. The trailer valve unit is also designed to be monostable and can be controlled in unison with the monostable first and second compressed air paths.

[0031] Furthermore, it is preferably proposed that the first trailer switching valve is configured as a first 2 / 3-way trailer switching valve, and the second trailer switching valve is configured as a second 2 / 3-way trailer switching valve. In this regard, the first trailer switching valve and the second trailer switching valve are configured identically to the switching valves of the first monostable valve unit and the second monostable valve unit. The same parts can be used here, thereby reducing costs.

[0032] It is preferably proposed that the first trailer switching valve has a first trailer switching valve interface connected to the second switching valve interface, a second trailer switching valve interface connected to the second shuttle valve, and a third trailer switching valve interface connected to one or the exhaust end. The second trailer switching valve preferably has a fourth trailer switching valve interface connected to the eighth switching valve interface, a fifth trailer switching valve interface connected to the second shuttle valve, and a sixth trailer switching valve interface connected to one or the exhaust end. In this way, the first trailer switching valve and the second trailer switching valve are connected to the first compressed air path and the second compressed air path, and then connected to the second shuttle valve on their side, similar to the switching valves of the first monostable valve unit and the second monostable valve unit. Subsequently, the higher of the pressures regulated here is always transmitted through the second shuttle valve, in this case specifically transmitted to the trailer. In this way, the same functions that have been provided for the tractor can also be implemented on the trailer.

[0033] In a second aspect, in an electronically controllable pneumatic brake system for a vehicle, in particular a commercial vehicle, comprising a first electronic control unit and a second electronic control unit, wherein the first electronic control unit and the second electronic control unit are designed so that they can at least partially replace each other in the event of a fault, the object mentioned at the beginning is solved by a parking brake valve assembly according to one of the above preferred embodiments of the parking brake valve assembly according to the first aspect of the invention, wherein the first electronic control unit is connected to the first monostable valve unit for providing a first switching signal thereto, and the second electronic control unit is connected to the second monostable valve unit for providing a second switching signal thereto. It should be understood that the parking brake valve assembly according to the first aspect of the invention and the electronically controllable pneumatic brake system according to the second aspect of the invention have identical and similar sub-aspects as the sub-aspects specifically set out in the dependent claims. In this regard, reference is made to the above content in its entirety.

[0034] If a trailer valve unit is provided, the electronically controllable pneumatic brake system according to the second aspect of the present invention preferably further proposes that the first trailer switching valve is controlled by the second electronic control unit, the second trailer switching valve is controlled by the first electronic control unit, and other switching signals are provided by them accordingly. In this way, cross switching can be achieved. Alternatively, preferably, the first trailer switching valve is controlled by the first electronic control unit, and the second trailer switching valve is controlled by the second electronic control unit.

[0035] In a third aspect, the object mentioned at the outset is achieved by a vehicle, in particular a commercial vehicle, comprising an electronically controllable pneumatic brake system according to one of the above-mentioned preferred embodiments of the electronically controllable pneumatic brake system according to the second aspect of the present invention. It should be understood that the vehicle according to the third aspect of the present invention also has the same or similar sub-aspects as the first two aspects of the present invention. In this regard, reference is made to the above content in its entirety.

[0036] The following will describe the embodiments of the present invention in conjunction with the accompanying drawings. These drawings may not necessarily represent the embodiments to scale, but these drawings may be drawn in a schematic and / or slightly deformed form for the purpose of illustration. In view of the supplement of the teachings that can be directly seen in the figures, reference is made to the relevant prior art. It should be taken into account here that various modifications and changes can be made to the form and details of the embodiments without departing from the general concept of the present invention. The features disclosed in the specification, drawings and claims of the present invention can basically improve the present invention in a separate form or in any combination. In addition, all combinations of at least two of the features disclosed in the specification, drawings and / or claims fall within the scope of the present invention. The general concept of the present invention is not limited to the exact form or details of the preferred embodiments shown and described below, nor is it limited to objects that are restricted compared to the objects claimed for protection in the claims. Within the measurement range proposed by the present invention, values ​​within the specified limits should also be disclosed as limits and can be used arbitrarily and claimed for protection. For simplicity, the same or similar parts or parts with the same or similar functions are marked with the same figure marks below. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] Further advantages, features and details of the present invention are explained by the following description of preferred embodiments with reference to the accompanying drawings; in which:

[0038] Figure 1 A first embodiment of a parking brake valve assembly is shown;

[0039] Figure 2 A second embodiment of a parking brake valve assembly is shown;

[0040] Figure 3 A nonlinear exhaust characteristic curve diagram is shown;

[0041] Figure 4 A third embodiment of a parking brake valve assembly is shown; and

[0042] Figure 5 An electronically controllable pneumatic brake system is shown. DETAILED DESCRIPTION

[0043] An electronically controllable pneumatic brake system 210 for a vehicle 200, in particular a commercial vehicle 202 (see Figure 5 ) of the parking brake valve assembly 1 (see Figure 1 ) has a first compressed air path 2 and a second compressed air path 4. A reserve pressure pV is supplied to both the first compressed air path 2 and the second compressed air path 4. It can also be provided that the first compressed air path 2 is supplied with a first reserve pressure pV1 and the second compressed air path 4 is supplied with a second reserve pressure pV2, for example, as will be referred to below Figure 5Detailed description. A first monostable valve unit 6 is provided in the first compressed air path 2, and a second monostable valve unit 8 is provided in the second compressed air path 4. The corresponding pressure can be regulated by switching the first monostable valve unit 6 or the second monostable valve unit 8. In the first compressed air path 2, the first parking brake pressure pF1 can be regulated by switching the first monostable valve unit 6, and in the second compressed air path 4, the second parking brake pressure pF2 can be regulated by switching the second monostable valve unit 8. The first compressed air path 2 and the second compressed air path 4 are connected to a first shuttle valve 10, which is configured to always regulate the higher of the first parking brake pressure pF1 and the second parking brake pressure pF2 into the parking brake pressure line 11. The parking brake pressure line 11 can then be directly or indirectly connected to the spring-accumulator brake cylinders 220a, 220b, 220c, 220d on their side, as in principle referred to. Figure 4 and Figure 5 As shown and further described below.

[0044] The first shuttle valve 10 is constructed as a so-called select-high-ventil and has a first shuttle valve interface 10.1 connected to the first compressed air path 2 to receive the first parking brake pressure pF1, a second shuttle valve interface 10.2 connected to the second compressed air path 4 to receive the second parking brake pressure pF2, and a third shuttle valve interface 10.3, which is constructed to always regulate the higher of the first parking brake pressure pF1 and the second parking brake pressure pF2 and is connected to the parking brake pressure line 11 for this purpose.

[0045] In this embodiment, the first monostable valve unit 6 has a first switching valve 12 and a second switching valve 14. Both switching valves 12 and 14 are monostable and both are Figure 1 The first switching position shown in is without current, in which the two switching valves exhaust the first compressed air path 2 and thus also exhaust the first shuttle valve interface 10.1. Specifically, the first switching valve 12 is configured as a first two-position three-way valve 13. The first switching valve 12 has a first switching valve interface 12.1 that receives a reserve pressure pV or a first reserve pressure pV1, a second switching valve interface 12.2, and a third switching valve interface 12.3 that is connected to the exhaust end 7. The second switching valve interface 12.2 is connected to the second switching valve 14. The second switching valve 14 is configured as a second two-position three-way valve 15. The second switching valve 14 has a fourth switching valve interface 14.1 that is connected to the second switching valve interface 12.2 and receives the pressure regulated thereby, a fifth switching valve interface 14.2, and a sixth switching valve interface 14.3, and the sixth switching valve interface 14.3 is in turn connected to one or the exhaust end 7. In Figure 1In the embodiment shown, the fifth switching valve port 14.2 is directly connected to the first shuttle valve port 10.1 via a corresponding line. However, it can also be provided that other elements are present here so that the fifth switching valve port 14.2 is only indirectly connected to the first shuttle valve port 10.1. The first switching valve 12 and the second switching valve 14 are pneumatically connected in series.

[0046] Both switching valves (i.e., the first switching valve 12 and the second switching valve 14) are connected to the first electronic control unit ECU1, which provides them with a first switching signal S1. That is, the first switching valve 12 and the second switching valve 14 switch together and receive the same first switching signal S1. In the first switching position of the first switching valve 12 without current, the second switching valve interface 12.2 is connected to the third switching valve interface 12.3, so that the reserve pressure pV cannot be conducted through the first switching valve 12. Only when the first switching valve 12 is switched from Figure 1 The first switching position shown switches to a second switching position in which the first switching valve connection 12.1 is connected to the second switching valve connection 12.2 ( Figure 1 (not shown), the reserve pressure pV can be conducted from the first switching valve interface 12.1 to the second switching valve interface 12.2 and provided to the fourth switching valve interface 14.1 accordingly. Figure 1 In the first switching position without current shown, no pressure is still regulated at the first shuttle valve connection 10.1, because the fourth switching valve connection 14.1 is closed and the fifth switching valve connection 14.2 is connected to the sixth switching valve connection 14.3, so that the first shuttle valve connection 10.1 is connected to one or the exhaust port 7 via the second switching valve 14. Only when the second switching valve 14 is also switched to the second switching position ( Figure 1 2), the pressure regulated by the first switching valve 12 is transmitted through the second switching valve 14 and regulated as the first parking brake pressure pF1 at the first shuttle valve port 10.1. That is, both the first switching valve 12 and the second switching valve 14 must be switched in order to regulate the first parking brake pressure pF1 at the first shuttle valve port 10.1.

[0047] The second compressed air path 4 is designed similarly, so that here too, what has already been said above in connection with the first compressed air path 2 applies accordingly.

[0048] The two switching valves (i.e., the third switching valve 16 and the fourth switching valve 18) in the second compressed air path 4 in the second monostable valve unit 8 are connected to the second electronic control unit ECU2, which provides them with a second switching signal S2. That is, the third switching valve 16 and the fourth switching valve 18 switch together and receive the same second switching signal S2. In the first switching position of the third switching valve 16 without current, the eighth switching valve interface 16.2 is connected to the ninth switching valve interface 16.3, so that the reserve pressure pV cannot be conducted through the third switching valve 16. Only when the third switching valve 16 is switched from Figure 1 The first switching position shown switches to a second switching position in which the seventh switching valve port 16.1 is connected to the eighth switching valve port 16.2 ( Figure 1 (not shown), the reserve pressure pV can be conducted from the seventh switching valve interface 16.1 to the eighth switching valve interface 16.2 and provided to the tenth switching valve interface 18.1 accordingly. Figure 1 In the first switching position without current shown, no pressure is still regulated at the second shuttle valve connection 10.2, because the tenth switching valve connection 18.1 is closed and the eleventh switching valve connection 18.2 is connected to the twelfth switching valve connection 18.3, so that the second shuttle valve connection 10.2 is connected to one or the exhaust port 7 via the fourth switching valve 18. Only when the fourth switching valve 18 is also switched to the second switching position ( Figure 1 2), the pressure regulated by the third switching valve 16 is transmitted through the fourth switching valve 18 and regulated as the second parking brake pressure pF2 at the second shuttle valve port 10.2. That is, both the third switching valve 16 and the fourth switching valve 18 must be switched in order to regulate the second parking brake pressure pF2 at the second shuttle valve port 10.2.

[0049] The first electronic control unit ECU1 and the second electronic control unit ECU2 are preferably independent of each other and are, for example, assigned to two different modules in the electronically controllable pneumatic brake system 210. Preferably, the first electronic control unit ECU1 is powered by a first voltage source Q1, and the second electronic control unit ECU2 is powered by a second voltage source Q2. The first voltage source Q1 and the second voltage source Q2 are also preferably independent of each other.

[0050] In this way, it can be ensured that as long as one of the first electronic control unit ECU1 and the second electronic control unit ECU2 or one of the first voltage source Q1 and the second voltage source Q2 is working properly, at least one of the first parking brake pressure pF1 and the second parking brake pressure pF2 can be regulated, so that when one of the two electronic control units ECU1 and ECU2 is working, the parking brake pressures pF1 and pF2 are regulated on the third shuttle valve interface 10.3, in which case the spring-accumulator brake cylinders 220a to 220d are kept released. Only when the first electronic control unit ECU1 or the first voltage source Q1 and the second electronic control unit ECU2 or the second voltage source Q2 fail and thus no longer provide or correctly provide the first switching signal S1 and the second switching signal S2, the first compressed air path 2 and the second compressed air path 4 are vented, and thus the spring-accumulator brake cylinders 220a to 220d are also vented and the vehicle 200 is braked.

[0051] Figure 2 A second embodiment of a parking brake valve assembly 1 is shown, wherein the same and similar elements are numbered with Figure 1 The same reference numerals are used. In this regard, reference is made to the above contents in their entirety. The following particularly emphasizes the differences with the first embodiment ( Figure 1 )’s difference.

[0052] The second embodiment is similar to the first embodiment ( Figure 1 ) is mainly different from the above in that an exhaust valve 20 is provided.

[0053] exist Figure 2 In the embodiment shown, the exhaust valve 20 is formed by a pressure limiter 22 and a throttle 24 arranged in parallel therewith, which allows overflow of the pressure limiter 22. The pressure limiter 22 itself is in turn connected to one or the exhaust port 7.

[0054] The combination of the exhaust valve 20 with the pressure limiter 22 and the throttle 24 allows a nonlinear exhaust gas characteristic curve E to be realized in a simple manner (see Figure 3 ). If the electronically controllable pneumatic brake system 210 fails and causes the first electronic control unit ECU1 and the second electronic control unit ECU2 to fail, so that the first switching signal S1 and the second switching signal S2 are no longer provided, the first compressed air path 2 and the second compressed air path 4 are connected to the exhaust valve 20 via the second switching valve 14 and the third switching valve 18 and thus exhausted. Then, the pressure limiter 22 first allows the pressure to be increased with a gradient G1 (see Figure 3) is exhausted to the partial brake pressure pLT, and once the boundary pressure (in this case the partial brake pressure pLT) is reached, the first shuttle valve port 10.1 and the second shuttle valve port 10.2 are exhausted to the full brake pressure pLV (which can preferably correspond to the ambient pressure) through the throttle 24, wherein this process is completed with a second gradient G2.

[0055] from Figure 3 It can be seen in particular that the first gradient G1 is much greater than the second gradient G2. At time t1 when both the first electronic control unit ECU1 and the second electronic control unit ECU2 fail and no longer provide the first switching signal S1 and the second switching signal S2, the third shuttle valve interface 10.3 is exhausted with the first gradient G1, wherein the first parking brake pressure pF1 or the second parking brake pressure pF2 (which can correspond to the reserve pressure pV) drops to the partial brake pressure pLT. If the partial brake pressure is reached (time t2), the pressure drops from the partial brake pressure pLT to the full brake pressure pLV with the second gradient G2. The full brake pressure pLV is then reached at time t3. From Figure 3 It can be seen that the time interval between the second moment t2 and the third moment t3 is much longer than the time interval between the first moment t1 and the second moment t2, that is, about 15.5 times longer. Figure 3 It can also be seen that the first gradient G1 is approximately 20 times greater than the second gradient G2, wherein the first gradient G1 is also nonlinear, while the second gradient G2 is substantially linear. More specifically, the first gradient G1 is formed according to an exponential function, wherein Figure 3 In the example shown, the average value of the first gradient G1 is about 4.2. Other magnitudes and ratios are also preferred, such as coefficients of 10 or greater. It is important that the first parking brake pressure pF1 or the second parking brake pressure pF2 is quickly exhausted to the partial brake pressure pLT to quickly achieve partial braking of the vehicle 200 and thus partial deceleration of the vehicle 200, and then the partial brake pressure pLT is slowly exhausted to the full brake pressure pLV to prevent the axles VA and HA from locking and the vehicle 200 from decelerating uncontrollably.

[0056] from Figure 1 and Figure 2The first pressure sensor 26 and the second sensor 28 can also be seen in FIG. The first pressure sensor 26 is arranged between the second switching valve 14 and the first shuttle valve 10, and then detects the first parking brake pressure pF1 regulated by the second switching valve 14. The second pressure sensor 28 is arranged between the fourth switching valve 18 and the first shuttle valve 10, and then detects the second parking brake pressure pF2 regulated by the fourth switching valve 18. The first pressure sensor 26 provides a first pressure signal SP1 to the first electronic control unit ECU1, and the second pressure sensor 28 provides a second pressure signal SP2 to the second electronic control unit ECU2. In this way, the first electronic control unit ECU1 and the second electronic control unit ECU2 can know whether the first switching valve 12 and the second switching valve 14 or the third switching valve 16 and the fourth switching valve 18 are working correctly, and whether the first parking brake pressure pF1 or the second parking brake pressure pF2 is actually regulated when the first switching signal S1 or the second switching signal S2 is output.

[0057] Figure 4 A third embodiment of the parking brake valve assembly 1 is shown. Figure 1 , Figure 2 ) are still marked with the same reference numerals, so that the above content is fully referenced. The following also particularly describes the first two embodiments ( Figure 1 , Figure 2 )’s difference.

[0058] Third embodiment ( Figure 4 ) and the first embodiment ( Figure 1 ) is that a trailer valve unit 30 is provided. The trailer valve unit 30 is used to control the trailer pressure pA, which can then be provided to the trailer (not shown) connected thereto via the trailer control valve 212. In this way, the trailer and the tractor can be braked in coordination. Since some trailers do not have spring-loaded brake cylinders but must be actively braked by positive brake pressure, an inverter may need to be provided in the trailer control valve 212. However, these embodiments are already known in principle and will not be described in detail below.

[0059] according to Figure 4 In the third embodiment shown, the trailer valve unit 30 is integrated into the parking brake valve assembly 1. In principle, it should be understood here that the first and second embodiments ( Figure 1 , Figure 2 ) valves need not be doubled, but only six switching valves are used in total, which can save two valves compared to doubling. For this reason, the trailer valve unit 30 is also integrated into the first compressed air path 2 and the second compressed air path 4.

[0060] Specifically, the first switching valve 12 and the third switching valve 16 are used as common switching valves for both the parking brake pressures pF1, pF2 and the trailer pressure pA. A first trailer pilot control line 40 leading to the first monostable trailer switching valve 32 is branched between the first switching valve 12 and the second switching valve 14 in the first compressed air path 2. In a similar manner, a second trailer pilot control line leading to the second monostable trailer switching valve 34 is branched between the third switching valve 16 and the fourth switching valve 18. The first monostable trailer switching valve 32 is assigned to the first compressed air path 2, and the second monostable trailer switching valve 34 is assigned to the second compressed air path 4.

[0061] Accordingly, when the first monostable trailer switching valve is Figure 4 The first switching position shown is switched to the second switching position ( Figure 4 (not shown), the first monostable trailer switching valve receives the pressure regulated by the first switching valve 12. When the first monostable trailer switching valve 32 also receives the pressure regulated by the first switching valve 12, the first monostable trailer switching valve 32 receives the pressure regulated by the first switching valve 12. Figure 4 The first switching position shown is switched to the second switching position ( Figure 4 In a similar manner, the second monostable trailer switching valve 34 receives the pressure regulated by the third switching valve 16, and when the second monostable trailer switching valve 34 is switched to the second switching position ( Figure 4 When the pressure is received from the third switching valve 16, the second shuttle valve 36 regulates the pressure received from the third switching valve 16. Then, the second shuttle valve 36 regulates the higher of the first trailer pilot pressure pAV1 and the second trailer pilot pressure pAV2 as the trailer pressure pA.

[0062] Specifically, the first monostable trailer switching valve 32 is configured as a first 2 / 3-way trailer switching valve 33. It has a first trailer switching valve interface 32.1 connected to the first trailer pilot control line 40, a second trailer switching valve interface 32.2 connected to the second shuttle valve 36 (more specifically, to the fourth shuttle valve interface 36.1), and a third trailer switching valve interface 32.3 connected to one or the exhaust end 7. Figure 4 In the illustrated first, de-energized switching position, the first monostable trailer switching valve 32 connects the second trailer switching valve port 32.2 to the third trailer switching valve port 32.3, thereby exhausting the fourth shuttle valve port 36.1. Figure 4 In a second switching position (not shown), the first trailer switching valve port 32 . 1 is connected to the second trailer switching valve port 32 . 2 , so that the first trailer pilot pressure pAV1 is controlled.

[0063] In a similar manner, the second monostable trailer switching valve 34 is constructed as a second 2 / 3-way trailer switching valve 35. It has a fourth trailer switching valve interface 34.1 connected to the second trailer pilot control line 32. In addition, it also has a fifth trailer switching valve interface 34.2 connected to the second shuttle valve 36 (more precisely, to the fifth shuttle valve interface 36.2) and a sixth trailer switching valve interface 34.3 connected to one or the exhaust port 7. Furthermore, in Figure 4 In the illustrated first, de-energized switching position of the second monostable trailer switching valve 34, the fifth trailer switching valve port 34.2 is connected to the sixth trailer switching valve port 34.3, so that the fifth shuttle valve port 36.2 is ventilated. Figure 4 In the second switching position of the second monostable trailer switching valve 34 (not shown), the fourth trailer switching valve port 34.1 is connected to the fifth trailer switching valve port 34.2, so that the second trailer pilot pressure pAV2 is regulated at the fifth shuttle valve port 36.2. Then, the second shuttle valve 36 regulates the higher of the first trailer pilot pressure pAV1 applied to the fourth shuttle valve port 36.1 and the second trailer pilot pressure pAV2 applied to the fifth shuttle valve port 36.2 at the sixth shuttle valve port 36.3, that is, as the trailer pressure pA.

[0064] In line with the first monostable valve unit 6 and the second monostable valve unit 8, the first monostable trailer switching valve 32 and the second monostable trailer switching valve 34 are also connected to the first electronic control unit ECU1 and the second electronic control unit ECU2. In this regard, the first monostable trailer switching valve 32 associated with the first compressed air path 2 is also controlled by the first electronic control unit ECU1 and switched by the first switching signal S1. In a similar manner, the second monostable trailer switching valve 34 associated with the second compressed air path 4 is controlled by the second electronic control unit ECU2 and in particular switched by the second switching signal S2.

[0065] from Figure 4 Another peculiarity can be seen in the figure, which will be described below.

[0066] The third shuttle valve 44 and the fourth shuttle valve 46 are pneumatically connected downstream of the first shuttle valve 10. Specifically, the higher of the first parking brake pressure pF1 and the second parking brake pressure pF2 is always regulated at the third shuttle valve port 10.3, which is connected to both the seventh shuttle valve port 44.1 of the third shuttle valve 44 and the tenth shuttle valve port 46.1 of the fourth shuttle valve 46 via the T-piece 34. The third shuttle valve 44 also has an eighth shuttle valve port 44.2 and a ninth shuttle valve port 44.3. The third shuttle valve is configured as a select-high-ventilator and the higher of the pressures applied to the seventh shuttle valve port 44.1 and the eighth shuttle valve port 44.2 is always regulated at the ninth shuttle valve port 44.3. The ninth shuttle valve port 44.3 is connected to the spring-accumulator brake cylinder 220a to vent or exhaust it.

[0067] In a similar manner, the fourth shuttle valve has an eleventh shuttle valve port 46.2 and a twelfth shuttle valve port 46.3 in addition to the tenth shuttle valve port 46.1, wherein the fourth shuttle valve 46 is configured to always adjust the higher of the pressures applied to the tenth shuttle valve port 46.1 and the eleventh shuttle valve port 46.2 at the twelfth shuttle valve port 46.3. The twelfth shuttle valve port 46.3 is connected to the spring-accumulator brake cylinder 220b to ventilate or exhaust it.

[0068] The eighth shuttle valve port 44.2 and the eleventh shuttle valve port 46.2 are connected to the parking brake relay valve 48 on their side, and the parking brake relay valve is supplied with pressure by the first reserve pressure pV1 and the second reserve pressure pV2 and receives the parking brake control pressure pSP as control pressure. The parking brake control pressure pSP is provided by other units such as a parking brake switch, a parking brake module, and is referred to Figure 5 Provided by the rear axle relay valve 214, in order to ventilate and release the spring-accumulator brake cylinders 220a, 220d in normal driving operation. However, the spring-accumulator brake cylinders 220a to 220d can also be used for additional braking or charged by an anti-compound function through the rear axle relay valve 214. In this way, the first parking brake pressure pF1 or the second parking brake pressure pF2 regulated by the parking brake valve assembly 1 can be over-controlled, so that if the parking brake valve assembly 1 does not work or does not work correctly, or the vehicle 200 is in a parking state without power, the spring-accumulator brake cylinders 220a to 220d can be ventilated and released as necessary.

[0069] Figure 5 An electronically controllable pneumatic brake system 210 is shown for a vehicle 200, wherein the vehicle 200 is designed as a commercial vehicle 202 and has a front axle VA and a rear axle HA and a second rear axle HA2. Figure 4 and Figure 5 By comparison, it can be seen that the parking brake valve assembly 1 ( Figure 4 ) implemented in Figure 5 In the electronically controllable pneumatic brake system 210 shown, the same and similar elements are still marked with the same reference numerals, so that the above content is fully referenced.

[0070] The electronically controllable pneumatic brake system 210 has a central module 222 which is connected to an autonomous driving unit 226 via a vehicle bus 224. In this case, the central module 224 is supplied with power by a first voltage source Q1.

[0071] In addition, the electronically controllable pneumatic brake system 210 has a first primary modulator 228 configured to control the front axle VA and including a first electronic control unit ECU1, and a second primary modulator 230 configured to control the rear axle and including a second electronic control unit ECU2. The first primary modulator 228 and the second primary modulator 230 are both connected to the autonomous driving unit 226 via the vehicle bus 224 and receive the electronic brake request signal SB therefrom, and they convert these electronic brake request signals to regulate the front axle brake pressure pBVA and the rear axle brake pressure pBHA. To this end, the first primary modulator 228 receives the first reserve pressure pV1 from the first compressed air reservoir 3, and the second primary modulator 230 receives the second reserve pressure pV2 from the second compressed air reservoir 5. The first primary modulator 228 is connected to the first voltage source Q1, and the second primary modulator 230 is connected to the second voltage source Q2. In addition, the first primary modulator 228 pneumatically controls the front axle relay valve 232, and the second primary modulator 230 pneumatically controls the rear axle relay valve 214. The front axle relay valve 232 and the rear axle relay valve 214 are themselves non-intelligent.

[0072] In order to indicate the redundancy level, a first secondary modulator 234 and a second secondary modulator 236 are also provided to receive the first reserve pressure pV1 or the second reserve pressure pV2 on their side. The first secondary modulator 234 and the second secondary modulator 236 are pneumatically constructed and have electromagnetically switchable valves (not shown), but they are not intelligent themselves. They are pneumatically connected to the brake value transmitter BST, which regulates the corresponding pressures on the first secondary modulator 234 and the second secondary modulator 236, which can then be converted by the first secondary modulator 234 and the second secondary modulator 236. The first secondary modulator 234 and the second secondary modulator 236 are pneumatically connected to the first primary modulator 228 and the second primary modulator 230, so that in the case of redundancy, the first primary modulator 228 and / or the second primary modulator 230 are pneumatically controlled when the first primary modulator 228 and / or the second primary modulator 230 fail. The corresponding electromagnetic switching valves in the first secondary modulator 234 and the second secondary modulator 236 are respectively cross-controlled, that is, in the case of failure of the first primary modulator 228, the first secondary modulator 234 pneumatically connected to the first primary modulator 228 for controlling the front axle VA receives an electrical switching signal for its electromagnetically switchable valve from the second primary modulator 230. In the case of failure of the second primary modulator 230, the second secondary modulator 236 pneumatically connected to the second primary modulator 230 for controlling the rear axle HA, HA2 receives a switching signal for its electromagnetically switchable valve from the first primary modulator 228.

[0073] In the event that both the first primary modulator 228 and the second primary modulator 230 fail, they do not output any of the above-described forms of the first switching signal S1 and the second switching signal S2, so that the first parking brake pressure pF1 and the second parking brake pressure pF2 are no longer regulated, and if necessary, the trailer pressure pA is no longer regulated. As a result, the spring-accumulator brake cylinders 220a to 220d of the vehicle 200 are exhausted and then compressed, and the trailer is braked if necessary. In this way, further redundancy is introduced in the event that both the first primary modulator 228 and the second primary modulator 230 fail. In this case, the vehicle 200 can still be braked in a controlled manner, preferably with reference to Figure 3 The nonlinear exhaust gas characteristic curve E is described. List of reference numerals (component of the description)

[0074] 1 Parking brake valve assembly

[0075] 2 First compressed air path

[0076] 3 First compressed air reservoir

[0077] 4 Second compressed air path

[0078] 5 Second compressed air reservoir

[0079] 6 First monostable valve unit

[0080] 7 Exhaust end

[0081] 8 Second monostable valve unit

[0082] 10 First shuttle valve

[0083] 10.1 First shuttle valve interface

[0084] 10.2 Second shuttle valve interface

[0085] 10.3 Third shuttle valve interface

[0086] 11 Parking brake pressure line

[0087] 12 First switching valve

[0088] 12.1 First switching valve interface

[0089] 12.2 Second switching valve interface

[0090] 12.3 Third switching valve interface

[0091] 13 1 / 2 3-way valve

[0092] 14 Second switching valve

[0093] 14.1 Fourth switching valve interface

[0094] 14.2 Fifth switching valve interface

[0095] 14.3 Sixth switching valve interface

[0096] 15 Second 2-position 3-way valve

[0097] 16 Third switching valve

[0098] 16.1 Seventh switching valve interface

[0099] 16.2 The eighth switching valve interface

[0100] 16.3 Ninth switching valve interface

[0101] 17 Third 2-position 3-way valve

[0102] 18 Fourth switching valve

[0103] 18.1 Tenth switching valve interface

[0104] 18.2 Eleventh switching valve interface

[0105] 18.3 Twelfth switching valve interface

[0106] 19 Fourth two-position three-way valve

[0107] 20 Exhaust valve

[0108] 22 Voltage Limiter

[0109] 24 throttle

[0110] 26. First pressure sensor

[0111] 28 Second pressure sensor

[0112] 30 Trailer valve unit

[0113] 32 First monostable trailer switching valve

[0114] 32.1 First trailer switching valve interface

[0115] 32.2 Second trailer switching valve interface

[0116] 32.3 Third trailer switching valve interface

[0117] 33 First and second position three-way trailer switching valve

[0118] 34 Second monostable trailer switching valve

[0119] 34.1 Fourth trailer switching valve interface

[0120] 34.2 Fifth trailer switching valve interface

[0121] 34.3 Sixth trailer switching valve interface

[0122] 35 Second 2-position 3-way trailer switching valve

[0123] 36 Second shuttle valve

[0124] 36.1 Fourth shuttle valve interface

[0125] 36.2 Fifth shuttle valve interface

[0126] 36.3 Sixth shuttle valve interface

[0127] 40 First trailer pilot control circuit

[0128] 42 Second trailer pilot control circuit

[0129] 43 T-piece

[0130] 44 Third shuttle valve

[0131] 44.1 Seventh shuttle valve interface

[0132] 44.2 Eighth shuttle valve interface

[0133] 44.3 Ninth shuttle valve interface

[0134] 46 Fourth shuttle valve

[0135] 46.1 Tenth shuttle valve interface

[0136] 46.2 Eleventh shuttle valve interface

[0137] 46.3 12th shuttle valve interface

[0138] 48 Parking brake relay valve

[0139] 200 vehicles

[0140] 202 Commercial vehicles

[0141] 210 Electronically controlled pneumatic brake system

[0142] 212 Trailer Control Valve

[0143] 214 Rear axle relay valve

[0144] 220a, 220b, 220c, 220d Spring-accumulated brake cylinder

[0145] 222 Central Module

[0146] 224 Vehicle Bus

[0147] 226 Autonomous Driving Unit

[0148] 228 First Primary Modulator

[0149] 230 Second Primary Modulator

[0150] 232 Front axle relay valve

[0151] 234 First secondary modulator

[0152] 236 Secondary Modulator

[0153] BST Braking Value Transmitter

[0154] E Exhaust characteristic curve

[0155] ECU1 First electronic control unit

[0156] ECU2 Second electronic control unit

[0157] G1 first gradient

[0158] G2 First Gradient

[0159] pA trailer pressure

[0160] pAV1 First trailer pilot pressure

[0161] pAV2 Second trailer pilot pressure

[0162] pF1 First parking brake pressure

[0163] pF2 Second parking brake pressure

[0164] pLT Partial brake pressure

[0165] pLV full brake pressure

[0166] pSP parking brake control pressure

[0167] pV Reserve pressure

[0168] pV1 First reserve pressure

[0169] pV2 Second reserve pressure

[0170] Q1 First voltage source

[0171] Q2 Second voltage source

[0172] S1 First switching signal

[0173] S2 Second switching signal

[0174] SB Electronic brake request signal

[0175] SP1 First pressure signal

[0176] SP2 Second pressure signal

[0177] VA front axle

[0178] HA rear axle

Claims

1. A parking brake valve assembly (1) for an electronically controllable pneumatic brake system (210) of a vehicle (200), the parking brake valve assembly comprising: a first compressed air path (2) receiving a first or second reserve pressure (pV, pV1, pV2), the first compressed air path having a first monostable valve unit (6) for providing a first parking brake pressure (pF1); a second compressed air path (4) receiving the first or second reserve pressure (pV, pV1, pV2), the second compressed air path having a second monostable valve unit (8) for providing a second parking brake pressure (pF2); as well as A first shuttle valve (10), the first shuttle valve having a first shuttle valve interface (10.1) connected to the first compressed air path (2) and receiving the first parking brake pressure (pF1), a second shuttle valve interface (10.2) connected to the second compressed air path (4) and receiving the second parking brake pressure (pF2), and a third shuttle valve interface (10.3) connectable to a spring-accumulator brake cylinder (220a, 220b, 220c, 220d), wherein the first shuttle valve (10) always adjusts the higher of the first parking brake pressure (pF1) and the second parking brake pressure (pF2) at the third shuttle valve interface (10.3), It is characterized in that the first monostable valve unit (6) is switched by a first electronic control unit (ECU1), and the second monostable valve unit (8) is switched by a second electronic control unit (ECU2).

2. The parking brake valve assembly (1) according to claim 1, wherein: The first monostable valve unit (6) is powered by a first voltage source (Q1), and the second monostable valve unit (8) is powered by a second voltage source (Q2).

3. The parking brake valve assembly (1) according to claim 1 or 2, wherein: The first monostable valve unit (6) has a first switching valve (12) and a second switching valve (14), which are connected to each other in a pressure-conducting manner so that the first parking brake pressure (pF1) is regulated only when the first and second switching valves (12, 14) are energized, and The second monostable valve unit (8) has a third switching valve (16) and a fourth switching valve (18) which are connected to one another in a pressure-conducting manner so that the second parking brake pressure (pF2) is controlled only when the third and fourth switching valves (16, 18) are energized.

4. The parking brake valve assembly (1) according to claim 3, wherein: The first switching valve (12) is configured as a first 2 / 3-way valve (13), the second switching valve (14) is configured as a second 2 / 3-way valve (15), the third switching valve (16) is configured as a third 2 / 3-way valve (17), and the fourth switching valve (18) is configured as a fourth 2 / 3-way valve (19), wherein: The first and second 2 / 3-way valves (13, 15) are pneumatically connected in series, and the third and fourth 2 / 3-way valves (17, 19) are pneumatically connected in series.

5. The parking brake valve assembly (1) according to claim 3, wherein: The first switching valve (12) has a first switching valve interface (12.1) for receiving a reserve pressure (pV, pV1, pV2), a second switching valve interface (12.2) connected to the second switching valve (14), and a third switching valve interface (12.3) connected to an exhaust end (7), wherein in a first switching position in which power is supplied, the first switching valve interface (12.1) is connected to the second switching valve interface (12.2), and in a second switching position in which power is not supplied, the second switching valve interface (12.2) is connected to the third switching valve interface (12.3); The second switching valve (14) has a fourth switching valve interface (14.1) connected to the second switching valve interface (12.2) of the first switching valve (12), a fifth switching valve interface (14.2) connected to the first shuttle valve interface (10.1), and a sixth switching valve interface (14.3) connected to the exhaust end (7), wherein in a first switching position with power on, the fourth switching valve interface (14.1) is connected to the fifth switching valve interface (14.2), and in a second switching position without power on, the fifth switching valve interface (14.2) is connected to the sixth switching valve interface (14.3); The third switching valve (16) has a seventh switching valve interface (16.1) for receiving a reserve pressure (pV, pV1, pV2), an eighth switching valve interface (16.2) connected to the fourth switching valve (18), and a ninth switching valve interface (16.3) connected to the exhaust end (7), wherein in a first switching position in which power is supplied, the seventh switching valve interface (16.1) is connected to the eighth switching valve interface (16.2), and in a second switching position in which no power is supplied, the eighth switching valve interface (16.2) is connected to the ninth switching valve interface (16.3); The fourth switching valve (18) has a tenth switching valve interface (18.1) connected to the eighth switching valve interface (16.2) of the third switching valve (16), an eleventh switching valve interface (18.2) connected to the second shuttle valve interface (10.2), and a twelfth switching valve interface (18.3) connected to the exhaust end (7), wherein, in a first switching position in which power is supplied, the tenth switching valve interface (18.1) is connected to the eleventh switching valve interface (18.2), and in a second switching position in which no power is supplied, the eleventh switching valve interface (18.2) is connected to the twelfth switching valve interface (18.3).

6. The parking brake valve assembly (1) according to claim 1 or 2, wherein: The first compressed air path (2) is connected to an exhaust valve (20) for exhausting the first shuttle valve port (10.1), and the second compressed air path (4) is connected to an exhaust valve (20) for exhausting the second shuttle valve port (10.2).

7. The parking brake valve assembly (1) according to claim 1 or 2, wherein: The first compressed air path (2) is connected to a single exhaust valve for exhausting the first shuttle valve port (10.1), and the second compressed air path (4) is connected to a single exhaust valve for exhausting the second shuttle valve port (10.2).

8. The parking brake valve assembly (1) according to claim 6, wherein: The exhaust valve (20) has a pressure limiter (22) and a throttle (24), wherein the throttle (24) is arranged in parallel with the pressure limiter (22) and allows overflow of the pressure limiter (22).

9. The parking brake valve assembly (1) according to claim 1 or 2, further comprising a trailer valve unit (30) for providing a trailer pressure (pA).

10. The parking brake valve assembly (1) according to claim 9, wherein: The trailer valve unit (30) is connected to the first and second compressed air paths (2, 4).

11. The parking brake valve assembly (1) according to claim 10, wherein: The trailer valve unit (30) receives a first trailer pilot pressure (pAV1) from the first compressed air path (2) and a second trailer pilot pressure (pAV2) from the second compressed air path (4), and always regulates the higher of the first or second trailer pilot pressure (pAV1, pAV2) as the trailer pressure (pA).

12. The parking brake valve assembly (1) according to claim 9, wherein: The trailer valve unit (30) comprises a first monostable trailer switching valve (32) connected to the first compressed air path (2) and a second monostable trailer switching valve (34) connected to the second compressed air path (4).

13. The parking brake valve assembly (1) according to claim 12, wherein: The first monostable trailer switching valve (32) is configured as a first 3 / 2-way trailer switching valve (33), and the second monostable trailer switching valve (34) is configured as a second 3 / 2-way trailer switching valve (35).

14. The parking brake valve assembly (1) according to claim 5, wherein: The trailer valve unit (30) for providing a trailer pressure (pA) comprises a first monostable trailer switching valve (32) connected to the first compressed air path (2) and a second monostable trailer switching valve (34) connected to the second compressed air path (4), wherein: The first monostable trailer switching valve (32) has a first trailer switching valve interface (32.1) connected to the second switching valve interface (12.2), a second trailer switching valve interface (32.2) connected to the second shuttle valve (36), and a third trailer switching valve interface (32.3) connected to one or the exhaust end (7), and The second monostable trailer switching valve (34) has a fourth trailer switching valve interface (34.1) connected to the eighth switching valve interface (16.2), a fifth trailer switching valve interface (34.2) connected to the second shuttle valve (36), and a sixth trailer switching valve interface (34.3) connected to one or the exhaust end (7).

15. An electronically controllable pneumatic brake system (210) for a vehicle (200), the electronically controllable pneumatic brake system comprising: a first electronic control unit (ECU1) and a second electronic control unit (ECU2), wherein the first and second electronic control units (ECU1, ECU2) are designed such that they can at least partially replace each other in the event of a fault; and A parking brake valve assembly (1) according to any one of claims 1 to 14, wherein the first electronic control unit (ECU1) is connected to a first monostable valve unit (6) for providing a first switching signal (S1) to the first monostable valve unit, and the second electronic control unit (ECU2) is connected to a second monostable valve unit (8) for providing a second switching signal (S2) to the second monostable valve unit (8).

16. A vehicle (200) comprising the electronically controllable pneumatic brake system (210) according to claim 15.

17. The vehicle (200) of claim 16, wherein: The vehicle (200) is a commercial vehicle (202).

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