Reliable parking brake valve arrangement with a changeover switch in series

Description

[0001] The invention relates to a parking brake valve arrangement for a pneumatic braking system of a commercial vehicle, comprising at least one first parking brake valve unit and at least one second parking brake valve unit, wherein the first parking brake valve unit is controlled by a first parking brake signal and can be switched from a first switching position to a second switching position, and the second parking brake valve unit is controlled by a second parking brake signal and can be switched from a first switching position to a second switching position. The invention further relates to a parking brake module for a pneumatic braking system of a commercial vehicle, comprising a parking brake reservoir connection for receiving reservoir pressure, a spring brake connection for providing parking brake pressure, and a parking brake valve arrangement as described above. The invention further relates to a commercial vehicle and a trailer.

[0002] Safety concepts are of paramount importance in electropneumatic braking systems for modern vehicles. Particularly in vehicles with automated or semi-automated driving functions, concepts for initiating emergency braking in the event of a fault or power failure in a control unit significantly contribute to the safety of the vehicle, its occupants, and other road users. Such concepts enable the vehicle to be brought to a safe stop in the event of a fault or power failure.

[0003] Basically, there are concepts that implement a fail-safe braking system using the service brake system and those that implement it using a parking brake system. Braking systems often implement both concepts to create two or more fallback levels based on the different concepts. Concepts based on a parking brake system have the advantage that by venting a pre-tensioned spring-applied brake cylinder, the vehicle can be brought to a secure stop without the need to pressurize a brake actuator with compressed air.

[0004] DE 10 2019 131 930 A1 already describes an electropneumatic parking brake module for an electronically controlled pneumatic braking system for a vehicle with a supply connection for receiving a supply pressure, at least one parking brake connection for connecting at least one parking brake cylinder, a main valve unit receiving the supply pressure, which is designed to control a spring pressure at the parking brake connection depending on a control pressure, and a pilot valve arrangement receiving the supply pressure for providing the control pressure, wherein the pilot valve arrangement has a bistable valve that is switchable between a first venting position and a second venting position, and a control unit for providing first and second switching signals at the pilot valve arrangement.

[0005] In the electropneumatic parking brake module shown in DE 10 2019 131 930 A1, the pilot valve arrangement has a monostable holding valve pneumatically connected in series with the bistable valve and arranged in a control line of the main valve unit, wherein the holding valve is open in an open position when de-energized, and the control unit is configured to hold the holding valve in the holding position to maintain the control pressure by means of the first switching signal, and a selection valve unit is arranged in the control line between the holding valve and a control port of the main valve unit, with a first selection valve port for receiving an additional control pressure provided at an additional brake pressure port, wherein the selection valve unit has a backstop characteristic at the first selection valve port such thatthat the first selection valve port opens in one flow direction from the auxiliary brake pressure port via a third selection valve port to the control port and closes against the flow direction.

[0006] A solution for venting spring-applied brake cylinders is disclosed in DE 10 2017 005 757 A1. The solution disclosed therein utilizes a pilot valve unit and a main valve unit, the pilot valve unit comprising an electromagnetic solenoid valve in the form of a bistable valve. In the solution disclosed therein, the main valve unit is formed by a relay valve. Depending on the switching position of the electromagnetic bistable valve, a control pressure is applied to the main valve unit, which then correspondingly controls a volumetric pressure for the spring-applied brake cylinders. A bistable valve is defined as a solenoid valve that has two stable switching positions, in particular a stable venting position and a stable venting position.For this purpose, energizing a first electromagnet can move the solenoid valve's armature into a first position, placing the solenoid valve in the venting position. Energizing a second electromagnet then moves the solenoid valve's armature into a second position, placing the solenoid valve in the venting position. If no other force acts on the armature, or if it can be mechanically and / or magnetically locked in these positions, the respective switching position is stable, as it can be maintained without further energizing.

[0007] A braking system with a further parking brake device of the same type is disclosed in DE 103 36 611 A1. It discloses a pressure-medium-operated braking system for a vehicle with a parking brake function, in which, as a result of manual actuation of an electric parking brake signal transmitter, at least one wheel brake of the braking system can be actuated without actuation of a brake pedal via an actuator that can be pressurized with the pressure medium. Based on this, a pressure-medium-operated braking system for a vehicle is disclosed in which a fixed-bar brake function, actuated via an electric signal transmitter, can be integrated with minimal effort while complying with the relevant safety regulations for braking systems.This is achieved by providing a parking brake module in which an electronic control unit and a valve assembly electrically actuated by the electronic control unit are integrated, wherein the electronic control unit activates the parking brake function upon receiving an electrical actuation signal from the parking brake signal transmitter requesting activation of the parking brake function, and wherein the electronic control unit controls the pressure medium application to the actuator within the framework of the parking brake function by means of the electrically actuated valve assembly.

[0008] Furthermore, such a system is also known, for example, from DE 10 2015 008 377 A1. The system disclosed therein comprises a parking brake module of a parking brake device with which the application of pressure medium to at least one brake actuator can be controlled. The parking brake module has an electronic control unit, at least one solenoid valve actuated by the control unit, a pressure medium quantity-increasing valve for applying pressure medium to the at least one brake actuator, and at least one pressure medium inlet through which pressure medium can be supplied to the parking brake module. The parking brake module has an emergency release pressure medium connection and a double check valve.The parking brake module has a first pressure medium line with which the emergency release pressure medium connection is fluidically connected via a check valve to the supply inlet of the pressure medium volume boosting valve in such a way that pressure medium flows through this first pressure medium line from the emergency release pressure medium connection to the pressure medium volume boosting valve if the pressure applied to the emergency release pressure medium connection is greater than the pressure applied to the supply inlet of the pressure medium volume boosting valve.The parking brake module has a second hydraulic line to which the emergency release hydraulic connection or another hydraulic connection of the parking brake module is fluidically connected to an inlet of the double check valve such that hydraulic fluid flows through this second hydraulic line from the emergency release hydraulic connection to the double check valve if the pressure at the emergency release hydraulic connection is greater than the pressure at the inlet of the double check valve. Alternatively, hydraulic fluid flows through this second hydraulic line from the other hydraulic connection to the double check valve if the pressure at the other hydraulic connection is greater than the pressure at the inlet of the double check valve.

[0009] To expand functionality and, in particular, to be able to vent and thus release the corresponding spring-applied brake cylinders of the parking brake regardless of whether a fault occurs at any of the various levels, be it the operational level or a redundancy level of the braking system, it is desirable that the spring-applied brake cylinders can be controlled via two independent paths for both venting and pressurizing. This should increase the range of functions and operational readiness of the vehicle, so that the highest possible level of functionality can be maintained even in the event of one or more faults in the braking system.

[0010] In a first aspect of the invention, the problem is solved by a parking brake valve arrangement of the first-mentioned type, in which the first parking brake signal and the second parking brake signal are independent of each other, and in which the first parking brake valve unit and the second parking brake valve unit are pneumatically connected in series between a parking brake reservoir port and a parking brake working port in such a way that the parking brake working port can be both vented and vented independently of the switching position of one parking brake valve unit by switching the other parking brake valve unit.

[0011] In this way, a parking brake valve arrangement is created that can be switched between a venting position and a releasing position (i.e., a release and a clamping position) by two independent signals: the first parking brake signal and the second parking brake signal. For example, if the first parking brake valve unit is controlled to be in a first switching position, the second parking brake valve unit can still be switched to its first and second switching positions by providing the second parking brake signal. In this case, for example, the parking brake working port is vented in the first switching position of the second parking brake valve unit, and vented in the second switching position. The same applies in the other case.

[0012] The parking brake reservoir connection can, for example, supply pressure from a parking brake circuit directly or, if necessary, via a changeover valve or a check valve. Alternatively, the parking brake reservoir connection can also supply parking brake pressure from a parking brake module or circuit already present in the vehicle. In this case, the parking brake valve assembly can serve to either direct the pressure supplied at the parking brake reservoir connection to the parking brake working connection or to vent it. The parking brake working connection is preferably connected to one or more spring-applied brake cylinders. The spring-applied brake cylinders can be located in the towing vehicle or in a trailer. Therefore, the parking brake valve assembly can also be implemented in a trailer.

[0013] The invention utilizes the fact that, through the proposed interconnection of the first and second valve units, both venting and venting of the parking brake working connection is possible, independent of the switching position of the other parking brake valve unit. Only switching of one parking brake valve unit is required at a time, regardless of the switching position of the other parking brake valve unit.

[0014] This allows the parking brake working port to be both vented and vented, regardless of whether, for example, the first or second parking brake valve unit can be switched on functionally, and thus the spring brake cylinders connected to the parking brake working port can be released or tightened independently of the functionality of one of the first and second parking brake valve units.

[0015] In a first preferred embodiment, the first parking brake valve unit is connected to the parking brake reservoir port and receives reservoir pressure from it. Preferably, the second parking brake valve unit can also be connected to the parking brake working port and control a parking brake working pressure at this port. As mentioned above, one or more spring-applied brake cylinders can then be connected to the parking brake working port. One or more downstream valves, such as a downstream relay valve or the like, can also be connected to the parking brake working port. A downstream relay valve can be advantageous if the parking brake working pressure provided by the second parking brake valve unit is to be amplified by volume before being supplied in amplified form to one or more spring-applied brake cylinders.

[0016] Preferably, the first parking brake signal is provided by a first signal source and the second parking brake signal by a second signal source, wherein the first and second signal sources are independent of each other. Preferably, the first and second signal sources are supplied from two independent voltage sources. For example, the first signal source is a central module of an electronically controlled pneumatic braking system, while the second signal source is a redundancy module of the electronically controlled pneumatic braking system, wherein the central module and the redundancy module are supplied from two independent voltage sources. The redundancy module can, for example, be integrated with a parking brake module, a trailer control module, or the like.

[0017] The central module can also be integrated with one or more axle modulators or other modules. It is also conceivable that the first and / or second parking brake signal is provided by a higher-level unit, such as an autonomous driving unit, an electronic steering unit, an air conditioning system, or the like. Furthermore, it is possible that one or both of the first and second parking brake signals can be provided manually, for example, via switches in the cockpit or a manually operated valve.

[0018] In a preferred embodiment, the first and second parking brake valve units are connected via a first valve line and a separate second valve line to implement a changeover function. This allows the first and second valve lines to alternately function as venting and venting lines. For example, if the second parking brake valve unit is in the first switching position, the first valve line could act as the venting line and the second as the venting line, with the first parking brake valve unit switched accordingly. By switching the second parking brake valve unit, it is then possible to switch between the first and second valve lines, connecting each to the parking brake working port.In such a case, the first parking brake valve unit can, for example, be designed to reverse the pneumatic venting of the first and second valve units. For instance, in the first switching position of the first parking brake valve unit, the first valve line is vented and the second valve line is vented. In the second switching position of the first parking brake valve unit, however, the first valve line is vented and the second valve line is vented.

[0019] For example, it is provided that the first parking brake valve unit can be used to selectively pressurize and vent either the first or the second valve line. For example, in the first switching position of the first parking brake valve unit, the first valve line is pressurized while the second valve line is vented, and in the second switching position of the first parking brake valve unit, the second valve line is pressurized while the second valve line is vented.

[0020] Preferably, the second parking brake valve unit can be used to selectively connect either the first valve line or the second valve line to the parking brake working port.

[0021] According to a preferred embodiment, the first parking brake valve unit is or comprises a 4 / 2-way valve with a first parking brake valve port, a second parking brake valve port, a third parking brake valve port, and a fourth parking brake valve port. Preferably, in the first switching position, the first parking brake valve port is connected to the second parking brake valve port, and the third parking brake valve port is connected to the fourth parking brake valve port. In the second switching position, preferably the first parking brake valve port is connected to the fourth parking brake valve port, and the third parking brake valve port is connected to the second parking brake valve port. Thus, the connection of the respective ports is reversed in the first and second switching positions.cross-connected, so that part of a two-way switching circuit can be implemented.

[0022] In a further preferred embodiment, the first parking brake valve unit comprises or consists of a first switching valve and a second switching valve. Preferably, both the first and the second switching valve are designed as 3 / 2-way valves. Both the first and the second switching valve are controlled and switched by means of the first parking brake signal. In this way, they are combined into a parking brake valve unit. The first parking brake valve unit and the second parking brake valve unit can also be referred to as the first and second parking brake valves, whereas in the described embodiment, the first and the second switching valve can then be considered the first and second valve parts of the first parking brake valve. Since the first and second switching valves are switched together by the first parking brake signal, they can also be combined and referred to as a single valve.By connecting the first and second switching valves, which are preferably designed as 3 / 2-way valves, a functionality can be achieved that corresponds to that of the described 4 / 2-way valve.

[0023] According to a further preferred embodiment, the second parking brake valve unit is or comprises a 3 / 2-way valve. The 3 / 2-way valve forming the second parking brake valve unit preferably has a fifth parking brake valve port, a sixth parking brake valve port, and a seventh parking brake valve port. In the first switching position, the fifth parking brake valve port is preferably connected to the sixth parking brake valve port, and in the second switching position, the seventh parking brake valve port is connected to the sixth parking brake valve port. The 3 / 2-way valve is preferably switched between the two switching positions by the second switching position.

[0024] Preferably, the parking brake valve assembly is configured so that the first parking brake signal is pneumatic or electrical, and / or the second parking brake signal is pneumatic or electrical. An electrical signal can be provided directly by a higher-level electronic control unit, which in turn generates or receives and transmits the signal. A pneumatic signal can be provided, for example, by electronically switchable solenoid valves, or by one or more manually operated spool valves. This is particularly preferred when the parking brake valve assembly is used in a trailer vehicle.

[0025] In a preferred embodiment of the parking brake valve arrangement, the first parking brake valve unit and / or the second parking brake valve unit is bistable. Preferably, the first parking brake valve unit and / or the second parking brake valve unit is electromagnetically bistable. For example, the first parking brake valve unit and / or the second parking brake valve unit is designed as a double solenoid valve with two stable magnetic detent poles. This can be achieved either by arranging two permanent magnets at opposite ends such that the armature is held in corresponding end positions, or by equipping the armature itself with corresponding magnetic components to hold it in both end positions. This can be achieved by one or two coils.These designs are known to experts, and for further details, reference is made to the relevant specialist knowledge.

[0026] In a second aspect, the invention solves the aforementioned problem by means of a parking brake module for a pneumatic braking system of a commercial vehicle, comprising a parking brake reservoir connection for receiving reservoir pressure, a spring accumulator connection for providing parking brake pressure, and a parking brake valve arrangement according to one of the aforementioned preferred embodiments of a parking brake valve arrangement according to the first aspect of the invention.

[0027] While the parking brake valve assembly may be designed to be integrated into an existing system, module, or arrangement, the parking brake module according to the second aspect of the invention is preferably designed to be used as a standalone unit. In addition to the features and functions described below, the parking brake module according to the second aspect of the invention may also include further functions, such as, in particular, all or some of the known functions of conventional parking brake modules for pressurizing and venting spring-applied brake cylinders. The parking brake module according to the second aspect of the invention may be located in both the towing vehicle and a trailer.Preferably, the parking brake working connection is connected to the spring brake connection, either directly or via one or more valves, such as a relay valve, as will be described in more detail below.

[0028] In a preferred embodiment of the parking brake module, it comprises a first pilot unit connected to the parking brake reservoir and receiving reservoir pressure from it. The first pilot unit is switchable to control a first control pressure, and this first control pressure is used to switch at least the first parking brake valve as the first parking brake signal. According to this embodiment, the first control pressure thus constitutes the first parking brake signal, making it a pneumatic first parking brake signal. Therefore, according to this embodiment, the first parking brake valve unit is pneumatically switched based on the first control pressure provided by the first pilot unit.

[0029] In a preferred embodiment of the parking brake module, it has a second pilot control unit, wherein the second pilot control unit is connected to the parking brake reservoir connection and receives reservoir pressure from it, wherein the second pilot control unit is switchable to control a second control pressure, and wherein the second control pressure is used to switch at least the second parking brake valve unit as a second parking brake signal. According to this embodiment, the second parking brake signal is also a pneumatic signal and is generated by the second control pressure. The second parking brake valve unit is therefore pneumatically switchable, and the second parking brake signal is pneumatically supplied by the pilot control unit.

[0030] In a preferred embodiment of the parking brake module, it comprises a first electronic control unit. The first electronic control unit preferably serves to control the first pilot control unit, but can also serve to directly control the first parking brake valve unit if the first parking brake valve unit is electrically switchable and the first parking brake signal is an electrical switching signal. Furthermore, the parking brake module preferably comprises a second electronic control unit for controlling the second pilot control unit or for directly controlling the second parking brake valve unit. The first and second electronic control units are preferably integrated into the parking brake module, but can also be arranged externally. The first and second electronic control units are preferably supplied from different and independent voltage sources.

[0031] In a preferred embodiment, the first or second parking brake signal is a manual pneumatic pressure applied to a hand-operated valve. Such a hand-operated valve can be integrated into or connected to the parking brake module. Preferably, the hand-operated valve is a manually actuated slide valve. Such hand-operated valves are particularly useful in trailers to allow the first and / or second parking brake signal to be manually applied, especially from outside the trailer. This enables manual venting and de-energizing of the spring brake cylinders.

[0032] It is further preferred that the parking brake module includes a relay valve which is connected to the parking brake reservoir port to receive the reservoir pressure and which is connected to the parking brake valve assembly. This relay valve receives the parking brake operating pressure from the parking brake valve assembly at a control port and, in response to receiving the parking brake operating pressure, controls the parking brake pressure at the spring brake port. The relay valve thus preferably serves to amplify the parking brake operating pressure by volume and then output it as the amplified parking brake pressure. This is particularly advantageous when one or more spring brake cylinders, which require a larger volume, are connected to the spring brake port.

[0033] In such an arrangement, a holding valve is preferably also provided, which is arranged between the parking brake valve arrangement and the relay valve, for locking in or out the parking brake working pressure.

[0034] According to a third aspect of the invention, the aforementioned problem is solved by a commercial vehicle with an electronically controlled pneumatic braking system and a parking brake module according to one of the preferred embodiments of a parking brake module described above, as described in the second aspect of the invention. It should be understood that the parking brake module according to the second aspect of the invention and the commercial vehicle according to the third aspect of the invention have the same and similar sub-aspects, as set forth in particular in the dependent claims. It can also be provided that the commercial vehicle has an electronically controlled pneumatic braking system and a parking brake valve arrangement according to the first aspect of the invention, which then preferably integrates the further devices or modules of the electronically controlled pneumatic braking system.

[0035] In a fourth aspect of the invention, the invention solves the aforementioned problem by means of a trailer with an electronically controlled pneumatic braking system and a parking brake module according to one of the preferred embodiments of a parking brake module described above in accordance with the second aspect of the invention, or by means of a parking brake valve arrangement according to the first aspect of the invention. The same applies to the trailer according to the fourth aspect of the invention as already stated above in accordance with the third aspect of the invention.

[0036] Embodiments of the invention are now described below with reference to the drawings. These drawings are not necessarily intended to represent the embodiments to scale; rather, where this is helpful for clarification, the drawings are presented in a schematic and / or slightly distorted form. With regard to additions to the teachings directly apparent from the drawings, reference is made to the relevant prior art. It should be noted that numerous modifications and changes concerning the form and detail of an embodiment can be made without deviating from the general idea of ​​the invention. The features of the invention disclosed in the description, the drawings, and the claims can be essential for the further development of the invention, both individually and in any combination.Furthermore, the invention encompasses all combinations of at least two of the features disclosed in the description, the drawings, and / or the claims. The general idea of ​​the invention is not limited to the exact shape or detail of the preferred embodiments shown and described below, nor is it limited to an object that would be restricted compared to the object claimed in the claims. Where specified dimensioning ranges are given, values ​​lying within the stated limits are also disclosed as limit values ​​and may be used and claimed as desired. For the sake of simplicity, identical or similar parts, or parts with identical or similar functions, are used below as reference numerals.

[0037] Further advantages, features and details of the invention will become apparent from the following description of the preferred embodiments and from the drawings; these show in: Fig. 1 a first embodiment of a parking brake valve arrangement according to the first aspect of the invention; Fig. 2 a second embodiment of a parking brake valve arrangement according to the first aspect of the invention; Fig. 3 a first embodiment of a parking brake module according to the second aspect of the invention; Fig. 4 a second embodiment of a parking brake module according to the second aspect of the invention; Fig. 5 a third embodiment of a parking brake module according to the second aspect of the invention; Fig. 6 a fourth embodiment of a parking brake module according to the second aspect of the invention; Fig. 7 a fifth embodiment of a parking brake module according to the second aspect of the invention; Fig. 8 a sixth embodiment of a parking brake module according to the second aspect of the invention; and Fig. 9 a seventh embodiment of a parking brake module according to the second aspect of the invention.

[0038] First, the following will be used as a starting point Figuren 1 and 2A parking brake valve assembly 1 is described in two different basic embodiments. The parking brake valve assembly 1 comprises a first parking brake valve unit 2 and a second parking brake valve unit 4. The first parking brake valve unit 2 and the second parking brake valve unit 4 are connected in series. The first parking brake valve unit 2 is connected to a parking brake reservoir port 6 (not specified here) and receives reservoir pressure pV from it. The second parking brake valve unit 4 is connected to a parking brake working port 8 (not specified here) and provides a parking brake working pressure pFA at it. The parking brake working pressure pFA can vary between ambient pressure and a higher or high pressure required to release spring-applied brake cylinders (in the Figuren 1 and 2(not shown) is suitable for releasing spring-applied brake cylinders. The first and second parking brake valve units 2, 4 are connected in series between the parking brake reservoir port 6 and the parking brake working port 8. A first valve line 10 and a second valve line 12 run parallel to each other between the first and second parking brake valve units 2, 4.

[0039] Specifically, in the Fig. 1 In the illustrated embodiment, the first parking brake valve unit 2 is formed by a 4 / 2-way valve 200, which has a cross-connection. In the illustrated embodiment shown here, the first parking brake valve unit 2 has ( Fig. 1 ) a first parking brake valve connection 2.1, a second parking brake valve connection 2.2, a third parking brake valve connection 2.3, and a fourth parking brake valve connection 2.4. The first parking brake valve unit 2 can be switched back and forth between a first switching position 2A and a second switching position 2B, but is spring-loaded and biased into the first switching position 2A. By triggering a first parking brake signal SF1 at the first parking brake valve unit 2, the first parking brake valve unit 2 is switched from the first switching position 2A, which is in Fig. 1 shown, in the second in Fig. 2 The first parking brake signal SF1 can be either electrical or pneumatic, depending on the specific design of the first parking brake valve unit 2. In the first switching position 2A of the first parking brake valve unit 2, the first port is connected to the second parking brake valve port 2.1, 2.2, and the third port is connected to the fourth parking brake valve port 2.3, 2.4. In the second switching position 2B of the first parking brake valve unit 2, the first parking brake valve port 2.1 is connected to the fourth parking brake valve port 2.4, and the second parking brake valve port 2.2 is connected to the third parking brake valve port 2.3. In the Fig. 1 In the specific embodiment shown, the first parking brake valve connection 2.1 is connected to the parking brake reservoir connection 6, and the third parking brake valve connection 2.3 is connected to a vent 3. The second parking brake valve connection 2.2 is connected to the first valve line 10, and the fourth parking brake valve connection 2.4 is connected to the second valve line 12. In the first switching position 2A ( Fig. 1 The first valve line 10 is therefore pressurized with the supply pressure pV, while the second valve line 12 is vented. If the first parking brake valve unit 2 is switched to the second switching position 2B, the connections are crossed over, so that the second valve line 12 is then pressurized with the supply pressure pV, while the first valve line 10 is vented.

[0040] The second parking brake valve unit 4 is located in the Fig. 1 In the illustrated embodiment, a 3 / 2-way valve 202 has a fifth parking brake valve connection 4.1, a sixth parking brake valve connection 4.2, and a seventh parking brake valve connection 4.3. The 3 / 2-way valve 202, which forms the second parking brake valve unit 4, is also spring-loaded in a first switching position 4A and can be switched to the second switching position 4B by providing a second switching signal SF2, which can again be electrical or pneumatic. Fig. 1 not shown. In the Fig. 1 In the first switching position 4A shown, the fifth parking brake valve connection 4.1 is connected to the seventh parking brake valve connection 4.2, while in the second switching position 4B, the seventh parking brake valve connection 4.3 is connected to the sixth parking brake valve connection 4.2. In the Fig. 1 In the switching position of the first and second parking brake valve units 2, 4 shown, the sixth parking brake valve port 4.2 is connected to the vent 3, while the seventh parking brake valve port 4.3 is closed. The sixth parking brake valve port 4.2 is connected to the parking brake working port 8 and controls the parking brake working pressure pFA. By switching the second parking brake valve unit 4 to the second switching position 4B, the parking brake working port 8 can therefore be vented in the embodiment shown here.

[0041] If, for example, the second parking brake valve unit 4 remains in the first switching position 4A, as in Fig. 1 If the parking brake signal SF2 is no longer applied, the parking brake working port 8 can still be vented. For this purpose, the first parking brake valve unit 2 must be switched on so that the pressure between the first and second valve lines 10, 12 is reversed. The second valve line 12 is no longer connected to the vent 3 and the first valve line 10 is no longer pressurized with the supply pressure pV, but rather the other way around. In this case, the second valve line 12 is pressurized with the supply pressure, and the fifth parking brake valve port 4.1 receives the supply pressure, which is then supplied to the... Fig. 1 The first switching position 4A of the second parking brake valve unit 4, as shown, is forwarded to the sixth parking brake valve port 4.2 and controlled there at the parking brake working port 8. Therefore, regardless of the respective switching positions of the first and second parking brake valve units 2, 4, the parking brake working port 8 can be vented or vented by switching either of the first or second parking brake valve units 2, 4.

[0042] In Fig. 2 is a to Fig. 1 An alternative switching position is shown in which the first parking brake valve unit 2 is not formed by a 4 / 2-way valve 200, but by a first switching valve 14 and a second switching valve 16, each configured as a 3 / 2-way valve. The first switching valve 14 has a first switching valve port 14.1, a second switching valve port 14.2, and a third switching valve port 14.3. In a first in Fig. 2 In the switching position 2A of the first parking brake valve unit 2 shown, the first switching valve port 14.1 is connected to the second switching valve port 14.2. In the second Fig. 2 In switching position 2B (not shown), the first switching valve port 14.1 is connected to the third switching valve port 14.3. In the Fig. 2 In the illustrated embodiment, the first switching valve port 14.1 is connected to the parking brake reservoir port 6 and thus corresponds to the first parking brake valve port 2.1. The second switching valve port 14.2 is connected to the second valve line 12 and thus corresponds to the fourth parking brake valve port 2.4. The third switching valve port 14.3 is connected to the first valve line 10 and thus corresponds to the second parking brake valve port 2.2. A second switching valve 16 is provided to change the venting and purging positions of the first and second valve lines 10 and 12. The second switching valve 16 has a fifth switching valve port 16.1, which is connected to the vent 3 and thus corresponds approximately in functionality to the third parking brake valve port 2.3. The second switching valve 16 also has a fifth switching valve port 16.The second switching valve 16 has two ports, one connected to the first valve line 10 and one to the second valve line 12. The second switching valve 16 can selectively close or vent the fifth and sixth switching valve ports 16.2 and 16.3, thus maintaining or venting the pressure in the first and second valve lines 10 and 12, respectively. The first switching valve 14 can either close the second or third switching valve port 14.2 and 14.3, thus maintaining the pressure in the corresponding first or second valve line 10 and 12, or pressurize the second or third switching valve port 14.2 and 14.3 with a supply pressure pV, thus correspondingly pressurizing the first or second valve line 10 and 12.The interconnections of the first and second switching valves 14, 16 are chosen such that, as long as the first parking brake signal SF1 is not provided and the first parking brake valve unit 2 is in the first in . Fig. 2 In the switch position 2A shown, the second valve line 12 is pressurized and the first valve line 10 is vented. When the first parking brake signal SF1 is provided, the switch position changes to the one shown. Fig. 2 The second switching position 2B, not shown, in which the first valve line 10 is pressurized with supply pressure pV and the second valve line 12 is connected to the vent 3 and thus vented.

[0043] In this way, a changeover circuit is achieved by the first and second parking brake valve units 2, 4, which, as in the Figuren 1 and 2The invention demonstrates that the device can be used in both the towing vehicle and the trailer, particularly for the actuation and de-energizing of spring-applied brake cylinders. According to the invention, the first and second parking brake signals SF1 and SF2 are provided by independent sources: the first parking brake signal SF1 is provided by a first signal source Q1, and the second parking brake signal SF2 is provided by a second signal source Q2. These first and second signal sources Q1 and Q2 can be electrical or pneumatic.

[0044] The further Figuren 3 bis 9 We now show specific embodiments of a parking brake module 100 in which the parking brake valve arrangement 1 according to the present invention is used. Only the parking brake valve arrangement 1 according to the first illustration in each case is shown as an example. Fig. 1 The illustrated embodiment is shown, wherein in all embodiments the Figuren 3 bis 9 It should be understood that the parking brake valve arrangement 1, as in Fig. 2 can be shown to be trained, and likewise always that which is in the Figuren 3 bis 9 The 4 / 2-way valve 200 shown can be replaced by the first and second switching valves 14, 16, which are described in relation to the Figuren 1 and 2 was described.

[0045] In Fig. 3 A parking brake module 100 is shown, which includes a first electronic control unit ECU1, forming a first signal source Q1. The parking brake module 100 includes a spring brake connection 102, which is arranged in a housing 104 of the parking brake module 100. The spring brake connection 102 is formed here by the parking brake working connection 8, and thus the parking brake valve arrangement 1 is directly connected to the spring brake connection 102 and directly controls the parking brake working pressure pFA as the parking brake pressure pF at this connection. The first electronic control unit ECU1 acts in the Fig. 3 The illustrated embodiment includes a first pilot control unit 110, which is essentially designed like known pilot control units of known parking brake modules. The first pilot control unit 110 comprises an inlet-outlet valve unit 112 with an inlet valve 113 and an outlet valve 114. The inlet valve 113 is designed as a 2 / 2-way valve with a first inlet valve port 113.1 and a second inlet valve port 113.2, wherein the first inlet valve port 113.1 is connected to the parking brake reservoir port 6 and receives reservoir pressure pV. The second inlet valve port 113.2 is connected to the first parking brake valve unit 2 and provides a first control pressure p1 to it, which here represents the first parking brake signal SF1. By providing a first switching signal S1 by the first electronic control unit ECU1, the inlet valve 113 can be opened into the second parking brake unit 2. Fig. 3 The valve is brought to the switching position not shown, in which the first control pressure p1 is controlled. When de-energized, the inlet valve 113 is in a closed switching position. The outlet valve 114 is designed as a 3 / 2-way valve and has a first outlet valve port 114.1, a second outlet valve port 114.2, and a third outlet valve port 114.3. The first outlet valve port 114.1 is connected to the first parking brake valve unit 2, the second outlet valve port 114.2 is connected to the vent 3, and the third outlet valve port 114.3 is connected to the first valve line 10. The third outlet valve port 114.3 could also be connected to the second valve line 12, depending on which of the first and second valve lines 10 and 12 are to be pressurized during normal operation. In the de-energized state, Fig. 3 In the switching position shown, the first outlet valve port 114.1 is connected to the third outlet valve port 114.3, so that the pressure released in the first valve line 10 is returned as the first control pressure p1. This is intended to achieve self-holding of the first parking brake valve unit 2. The pressure released by this unit into the first valve line 10 is returned via the outlet valve 114. By providing the second switching signal S2, the outlet valve 114 can be moved into a venting position in which the first control pressure p1 can be released via the vent 3.

[0046] The second parking brake valve unit 4 is located in the Fig. 3 In the illustrated embodiment, a manual valve 130 is connected, which can be designed, in particular, as a spool valve. Here, the manual valve 130 forms the second signal source Q2. The manual valve 130 is shown adjacent to the parking brake module 100, but can also be located away from it, particularly on the outside of a trailer. The manual valve 130 has a first manual valve connection 130.1, a second manual valve connection 130.2, and a third manual valve connection 130.3. The first manual valve connection 130.1 is connected to the second parking brake valve unit 4 and provides a manual pressure pM to it, which here represents the second parking brake signal SF2. The second manual valve connection 130.2 is connected to the parking brake reservoir connection 6 and receives reservoir pressure pV. However, the second manual valve connection 130.2 could also be connected separately from the parking brake reservoir connection 6 to a reservoir pressure source.The in . Fig. 3 The connection shown merely illustrates that both the parking brake reservoir connection 6 and the second manual valve connection 130.2 are supplied from the same compressed air reservoir. The third manual valve connection 130.3 is connected to a vent 3. By moving the manual valve 130 to the second in Fig. 3 In the switching position not shown, the manually controlled pressure pM can therefore be vented, so that the second parking brake valve unit 4 falls spring-loaded into the first switching position 4A, which in Fig. 3 shown.

[0047] In the normal operating condition of the vehicle, in which a parking brake module 100 is installed according to Fig. 3 Once installed, the first switching signal S1 should be provided to move the first parking brake valve unit 2 into the second one. Fig. 3 to bring to the switching position not shown, so that the first valve line 10 is vented. The pressure released in the first valve line 10 is returned via the unswitched outlet valve 114 and is maintained as the first control pressure p1, so that the first parking brake valve unit 2 remains in the second switching position 2B. At the same time, the hand valve 130 is in the Fig. 3 shown switch position, so that the manual pressure pM is controlled, which moves the second parking brake valve unit 4 into the second in Fig. 3 The switch position 4B (not shown) activates, allowing the supply pressure pV to be controlled from the first valve line 10 and the parking brake pressure pF to be released. This allows the spring brake cylinders connected to the spring brake port 102 to be vented and released. Now, when the vehicle is parked, the second switching signal S2 opens the outlet valve 114 into the second position. Fig. 3 The switch position not shown is moved so that the first control pressure p1 is vented and the first parking brake valve unit 2 is moved to the first switch position 2A as shown. Fig. 3 The first valve line 10 is then depressurized. The spring brake connection 102 is also vented via the second parking brake valve unit 4, so that the spring brake cylinders connected to the spring brake connection 102 are vented and compressed. Now, an operator can vent the manually controlled pressure pM by actuating the hand valve 130, so that the second parking brake valve unit 4 also engages the first. Fig. 3 The switch position shown, 4A, is activated so that both the first and second parking brake valve units 2, 4 are engaged. Fig. 3 The switch positions shown are assumed. In these positions, it can be seen that the supply pressure pV is controlled via the second and fourth parking brake valve connections 2.3, 2.4 into the second valve line 12 and from there via the fifth parking brake valve connection 4.1 and the sixth parking brake valve connection 4.2 at the spring brake connection 102, so that subsequently the spring brake cylinders connected to the spring brake connection 112 can be vented and thus released.

[0048] The in Fig. 4 The embodiment shown is based on the one described in Fig. 1 The illustrated embodiment is such that identical and similar elements are provided with the same reference numerals, and only the differences will be discussed below. In contrast to the embodiment according to... Fig. 3 The inlet-outlet valve unit 112 is formed by a single bistable valve 118, which has two electromagnetic detent positions and thus provides electromagnetic bistability. The bistable valve 118 has a first bistable valve port 118.1, which is connected to the parking brake reservoir port 6 and receives reservoir pressure pV; a second bistable valve port 118.2, which is connected to the first parking brake valve unit 2 and can control the first control pressure p1 to embody the first parking brake signal SF1; and a third bistable valve port 118.3, which is connected to the vent 3. By switching the bistable valve 118 based on a third switching signal provided by the first electronic control unit ECU1, either the first control pressure p1 can be supplied or vented.

[0049] In the first embodiment according to Fig. 3 A first pressure sensor 160 is already shown, which provides a first pressure signal SD1 to the first electronic control unit ECU1. The first pressure signal SD1 represents the pressure present in the first valve line 10. The first pressure signal SD1 can therefore be used to verify the plausibility of the controlled parking brake pressure pF and also to verify the switching positions of the first and second parking brake valve units 2, 4. In addition to this first pressure sensor 116, the parking brake module 100 comprises, according to Fig. 4 The system also includes a second pressure sensor 162, which provides a second pressure signal SD2 to the first electronic control unit ECU1. The second pressure signal SD2 represents the pressure controlled at the parking brake working port 8, in the embodiment shown here the parking brake working pressure pFA. This signal can also be used for plausibility checks and to determine the switching positions of the valves.

[0050] The in Fig. 5 The illustrated embodiment of the parking brake module 100 is based on the previous embodiment, so that identical and similar elements are provided with the same reference numerals and, in this respect, reference is made in full to the above description. The first parking brake valve unit 2 is in accordance with the one described in Fig. 3 as shown in the embodiment, as is the first pilot control unit 110, which provides the first control pressure p1 to the first parking brake valve unit 2.

[0051] In contrast to the previous embodiments, the second parking brake valve unit 4 is not actuated by a manual pressure pM, but by a second control pressure p2, which in the embodiment shown here ( Fig. 5 ) the second parking brake signal SF2. A second pilot control unit 120 is provided to supply the second control pressure p2. The second pilot control unit 120 is controlled by a second electronic control unit ECU2, here by a fourth switching signal S4. The second pilot control unit 120 is bistable, preferably electromagnetically bistable, and comprises a further bistable valve 122 with a further first bistable valve port 122.1, a further second bistable valve port 122.2, and a further third bistable valve port 122.3. The further first bistable valve port 122.1 is connected to the parking brake reservoir port 6 and receives reservoir pressure from it. The further second bistable valve port 122.2 is connected to the second parking brake valve unit 4 and provides the second control pressure p2 at it. The further third bistable valve port 122.3 is connected to the vent 3. By alternately switching the further bistable valve 122, the second control pressure p2 can therefore be provided or vented.

[0052] In the Fig. 5 In the illustrated embodiment, a third and a fourth pressure sensor 163, 164 are further provided, both of which detect the pressure controlled at the parking brake working connection 8 and accordingly provide third and fourth pressure signals SD3, SD4 representing this to the first electronic control unit ECU1 and the second electronic control unit ECU2 respectively.

[0053] Even though the parking brake module 100 is shown here as a single unit, it should be understood that the individual subgroups, comprising in a first subgroup the first electronic control unit ECU1, the first pilot control unit 110 and the first parking brake valve unit 2 together with the first and third pressure sensors 160, 163, can form a single unit, and a second subgroup comprising the second electronic control unit ECU2, the second pilot control unit 120, the second parking brake valve unit 4 and the fourth pressure sensor 164 can form a second independent unit.

[0054] The in Fig. 6 The embodiment shown is based on the one described in Fig. 4 and in Fig. 5 The embodiment shown, wherein identical and similar elements are provided with the same reference numerals, so that full reference is made to the above description. In the embodiment shown Fig. 6 In the illustrated embodiment, the first pilot control unit 110 is provided for the first parking brake valve unit 2, which here according to Fig. 4 is equipped with the bistable valve 118 and the second pilot unit 120 is provided for the second parking brake valve unit 4, which is equipped with the further bistable valve 122 according to Fig. 5 is provided. According to the exemplary embodiments shown in the Fig. 3 bis 6 What they have in common is that the second parking brake valve unit 4 is directly connected to the spring brake connection 102, and thus the parking brake working connection 8 forms the spring brake connection 102 or is directly connected to it. In the embodiments now to be described, Fig. 7 bis 9 A relay valve 140 is provided in each case, which is connected between the parking brake working port 8 and the spring brake port 102, thus amplifying the parking brake working pressure pFA by volume and then controlling it as the parking brake pressure pF.

[0055] The in Fig. 7 The parking brake module 100 shown includes, as an additional special feature, the already existing Fig. 1 A known parking brake valve arrangement 1, wherein the 4 / 2-way valve 200, which forms the first parking brake valve unit 2, is bistable and can therefore be switched electromagnetically bistable between the first and second switching positions 2A, 2B by providing a fifth switching signal, which can be supplied by the second electronic control unit ECU2. The fifth switching signal S5 thus forms the first parking brake signal SF1. Likewise, the 3 / 2-way valve, which forms the second parking brake valve unit 4, is also bistable, likewise electromagnetically bistable, and can be switched between the first and second switching positions 4A, 4B by a sixth switching signal S6, so that the sixth switching signal, which is supplied by the first electronic control unit ECU1, represents the second parking brake signal SF2.The first and second parking brake signals SF1, SF2 are in the embodiment shown here (. Fig. 7 ) also electrically. The relay valve 140 is designed according to conventional relay valves and has a relay valve supply port 140.1, which is connected to the parking brake supply port 6 and receives supply pressure pV, a relay valve working port 140.2, which is connected to the spring brake port 102 and controls the parking brake pressure pF, a relay valve vent port 140.3, which is connected to a vent, and a relay valve control port 140.4, which receives the parking brake working pressure pFA.

[0056] As a further difference from the previous embodiments, a holding valve 150 is provided, which is arranged between the parking brake valve assembly 1 and the relay valve 140, for locking or unlocking the parking brake working pressure pFA. Once the parking brake working pressure pFA has been released, the holding valve 150 can be opened into the Fig. 7 The switching position not shown can be moved by providing a seventh switching signal S7, so that the holding valve 150 is then in the closed position. Fig. 7 The switching position not shown is in which the parking brake working pressure pFA is locked in at the relay valve control port 140.4. Consequently, the parking brake pressure pF is controlled, regardless of the switching positions of the first and second parking brake valve units 2, 4.

[0057] As a further special feature, the parking brake module 100 in the embodiment shown here includes an anti-compound port 170, as is essentially known in the prior art. A release pressure pZ can be controlled at the anti-compound port 170, in particular manually. Furthermore, a changeover valve is provided to control either the release pressure pZ or the parking brake working pressure pFA at the relay valve control port 140.4. This changeover valve is designed as a select-high valve to control the higher of the release pressure pZ and the parking brake working pressure pFA at the relay valve control port 140.4.

[0058] Furthermore, a fifth and sixth pressure sensor 165, 166 are provided, wherein the fifth pressure sensor provides a fifth pressure signal SD5 to the second electronic control unit ECU2 and the sixth pressure sensor 166 provides a sixth pressure signal SD6 to the first electronic control unit ECU1, each representing the parking brake pressure pF.

[0059] The in Fig. 8 The illustrated embodiment represents a mixture of the embodiment according to Fig. 7 and Fig. 4 The parking brake valve arrangement 1 initially corresponds to that shown in the diagram. Fig. 4 The first parking brake valve unit 2 also includes the first pilot unit 110 with the bistable valve 118, which is controlled by the first electronic control unit ECU1 via the third switching signal S3. The second parking brake valve unit 4 is in turn controlled by a manual pressure pM, which can be provided, for example, by a hand valve 130 or by another unit. Downstream of the parking brake valve assembly 1 are the holding valve 150, the changeover valve 172, and the relay valve 140, as described in relation to Fig. 7 described. Identical and similar elements are marked with the same reference symbols, so that the above description is fully referenced.

[0060] The in Fig. 9 The embodiment shown is essentially based on the one described in Fig. 8 in the illustrated embodiment, wherein the second parking brake signal SF2 is not generated by the manual pressure pM, but by the second control pressure p2, as shown in Fig. 5 known, formed. Just as from Fig. 5 The second control pressure p2 is provided by the further bistable valve 122, which is part of the second pilot control unit 120 and is controlled by the fourth switching signal S4 from the second electronic control unit ECU2. Identical and similar elements are again designated with the same reference numerals, so that the above description applies in full. REFERENCE MARK LIST (Part of the description)

[0061] 1 Parking brake valve assembly 2 First parking brake valve unit 2.1 First parking brake valve connection 2.2 Second parking brake valve connection 2.3 Third parking brake valve connection 2.4 Fourth parking brake valve connection 2A First switching position 2B Second switching position 3 Vent 4 Second parking brake valve unit 4.1 Fifth parking brake valve connection 4.2 Sixth parking brake valve connection 4.3 Seventh parking brake valve connection 4A First switching position 4B Second switching position 6 Parking brake reservoir connection 8 Parking brake working connection 10 First valve line 12 Second valve line 14 First switching valve 14.1 First switching valve connection 14.2 Second switching valve connection 14.3 Third switching valve connection 16 Second switching valve 16.1 Fourth switching valve connection 16.2 Fifth switching valve connection 16.3 Sixth switching valve connection 100 Parking brake module 102 Spring accumulator connection 104 Housing 110 First pilot control unit 112 Inlet-outlet valve unit 113 Inlet valve 113.1. First inlet valve connection 113.2 Second inlet valve connection 114 Exhaust valve 114.1 First exhaust valve connection 114.2 Second exhaust valve connection 114.3 Third exhaust valve connection 118 Bistable valve 118.1 First bistable valve connection 118.2 Second bistable valve connection 118.3 Third bistable valve connection 120 Second pilot unit 122 Further bistable valve 122.1 Further first bistable valve connection 122.2 Further second bistable valve connection 122.3 Further third bistable valve connection 130 Manual valve 130.1 First manual valve connection 130.2 Second manual valve connection 130.3 Third manual valve connection 140 Relay valve 140.1 Relay valve - reservoir connection 140.2 Relay valve - working connection 140.3 Relay valve vent connection 140.4 Relay valve control connection 160 First pressure sensor 162-166 Second to sixth pressure sensor 170 Anti-compound connection 172 Changeover valve 2004 / 2-way valve 2023 / 2-way valve ECU1 First electronic control unit ECU2 Second electronic control unit p1 First control pressure p2 Second control pressure pF Parking brake pressure pFA Parking brake working pressure pM Manual pressure pV Reservoir pressure Q1 First signal source Q2 Second signal source S1-S7 First to seventh switching signal SD1-SD6 First to sixth pressure signal SF1 First parking brake signal SF2 Second parking brake signal.

Claims

1. Parking brake valve assembly (1) for a pneumatic brake system of a commercial vehicle, comprising at least one first parking brake valve unit (2) and at least one second parking brake valve unit (4), the first parking brake valve unit (2) being controlled by a first parking brake signal (SF1) and being switchable from a first switching position (2A) to a second switching position (2B), and the second parking brake valve unit (4) being controlled by a second parking brake signal (SF2) and being switchable from a first switching position (4A) to a second switching position (4B), the first parking brake signal (SF1) and the second parking brake signal (SF2) being independent of one another, and characterized in that the first parking brake valve unit (2) and the second parking brake valve unit (4) are pneumatically connected in series between a parking brake supply terminal (6) and a parking brake working terminal (8) in such a way that the parking brake working terminal (8) can be both ventilated and vented, independently of the switching position (2A, 2B, 4A, 4B) of one parking brake valve unit (2, 4), by switching the relevant other parking brake valve unit (2, 4).

2. Parking brake valve assembly (1) according to claim 1, wherein the first parking brake valve unit (2) is connected to the parking brake supply terminal (6) and receives supply pressure (pV) therefrom.

3. Parking brake valve assembly (1) according to claim 1 or claim 2, wherein the second parking brake valve unit (4) is connected to the parking brake working terminal (8) and modulates a parking brake working pressure (pFA) at said terminal.

4. Parking brake valve assembly (1) according to any of the preceding claims, wherein the first parking brake signal (SF1) is provided by a first signal source (Q1) and the second parking brake signal (SF2) is provided by a second signal source (Q2), wherein the first signal source (Q1) and the second signal source (Q2) are independent of one another, in particular are supplied from two independent voltage sources.

5. Parking brake valve assembly (1) according to any of the preceding claims, wherein, in order to implement a changeover switching function, the first parking brake valve unit (2) and the second parking brake valve unit (4) are connected to one another via a first valve line (10) and a second valve line (12) which is separate therefrom.

6. Parking brake valve assembly (1) according to claim 5, wherein, by means of the first parking brake valve unit (2), selectively the first valve line (10) or the second valve line (12) can be pressurized with supply pressure (pV) and vented.

7. Parking brake valve assembly (1) according to claim 5 or claim 6, wherein, by means of the second parking brake valve unit (4), selectively the first valve line (10) or the second valve line (12) can be connected to the parking brake working terminal (8).

8. Parking brake valve assembly (1) according to any of the preceding claims, wherein the first parking brake valve unit (2) is a 4 / 2-way valve (200) comprising a first parking brake valve terminal (2.1), a second parking brake valve terminal (2.2), a third parking brake valve terminal (2.3) and a fourth parking brake valve terminal (2.4), wherein in the first switching position (2A), the first parking brake valve terminal (2.1) is connected to the second parking brake valve terminal (2.2), and the third parking brake valve terminal (2.3) is connected to the fourth parking brake valve terminal (2.4), and in the second switching position (2B), the first parking brake valve terminal (2.1) is connected to the fourth parking brake valve terminal (2.4), and the third parking brake valve terminal (2.3) is connected to the second parking brake valve terminal (2.2).

9. Parking brake valve assembly (1) according to any of the preceding claims 1 to 7, wherein the first parking brake valve unit (2) comprises a first switching valve (14) and a second switching valve (16), each of which is designed as a 3 / 2-way valve, wherein both the first switching valve (14) and the second switching valve (16) are controlled by means of the first parking brake signal (SF1).

10. Parking brake valve assembly (1) according to any of the preceding claims, wherein the second parking brake valve unit (4) is a 3 / 2-way valve (202) comprising a fifth parking brake valve terminal (4.1), a sixth parking brake valve terminal (4.2) and a seventh parking brake valve terminal (4.3), wherein in the first switching position (4A), the fifth parking brake valve terminal (4.1) is connected to the sixth parking brake valve terminal (4.2), and in the second switching position (4B), the seventh parking brake valve terminal (4.3) is connected to the sixth parking brake valve terminal (4.2).

11. Parking brake valve assembly (1) according to any of the preceding claims, wherein the first parking brake signal (SF1) is pneumatic or electric and / or the second parking brake signal (SF2) is pneumatic or electric.

12. Parking brake valve assembly (1) according to any of the preceding claims, wherein the first parking brake valve unit (2) and / or the second parking brake valve unit (4) is of bistable design.

13. Parking brake module (100) for a pneumatic brake system of a commercial vehicle, comprising a parking brake supply terminal (6) for receiving supply pressure (pV), a spring-loaded terminal (102) for providing a parking brake pressure (pF), and a parking brake valve assembly (1) according to any of claims 1 to 12.

14. Parking brake module (100) according to claim 13, comprising a first pilot control unit (110) which is connected to the parking brake supply terminal (6) and receives supply pressure (pV) therefrom, wherein the first pilot control unit (110) is switchable in order to modulate a first control pressure (p1), wherein the first control pressure (p1) for switching at least the first parking brake valve unit (2) is modulated as a first parking brake signal (SF1) thereat.

15. Parking brake module (100) according to claim 13 or claim 14, comprising a second pilot control unit (120) which is connected to the parking brake supply terminal (6) and receives supply pressure (pV) therefrom, wherein the second pilot control unit (120) is switchable in order to modulate a second control pressure (p1), wherein the second control pressure (p2) for switching at least the second parking brake valve unit (4) is modulated as a second parking brake signal (SF2) thereat.

16. Parking brake module (100) according to claim 14, comprising a first electronic control unit (ECU1) for controlling the first pilot control unit (110).

17. Parking brake module (100) according to claim 15, comprising a second electronic control unit (ECU2) for controlling the second pilot control unit (120).

18. Parking brake module (100) according to any of claims 13 to 17, wherein the first parking brake signal (SF1) or the second parking brake signal (SF2) is a manual pneumatic pressure (pM) of a hand valve (130).

19. Parking brake module (100) according to any of claims 13 to 18, comprising a relay valve (140) which is connected to the parking brake supply terminal (6) for receiving supply pressure (pV), and which is connected to the parking brake valve assembly (1) and receives, at a control terminal (140.4), the parking brake working pressure (pFA) from the parking brake valve assembly (1) and, in response to receiving the parking brake working pressure (pFA), modulates the parking brake pressure (pF) at the spring-loaded terminal (8).

20. Parking brake module (100) according to claim 19, comprising a holding valve (150) for locking in or locking out the parking brake working pressure (pFA), which holding valve is arranged between the parking brake valve assembly (1) and the relay valve (140).

21. Commercial vehicle comprising an electronically controllable pneumatic brake system and a parking brake module (100) according to any of claims 13 to 20.

22. Trailer comprising an electronically controllable trailer brake system and a parking brake module (100) according to any of claims 13 to 20.