ELECTROPNEUMATIC BRAKE SYSTEM, VEHICLE, METHOD FOR OPERATING AN ELECTROPNEUMATIC BRAKE SYSTEM WITH AN EMERGENCY RELEASE VALVE UNIT, USE OF AN EMERGENCY RELEASE VALVE UNIT IN AN ELECTROPNEUMATIC BRAKE SYSTEM

Description

[0001] The invention relates to an electropneumatic braking system according to the preamble of claim 1. The invention further relates to a vehicle with an electropneumatic braking system of the type mentioned above, a method for operating an electropneumatic braking system with an emergency release valve unit and a use of an emergency release valve unit in an electropneumatic braking system.

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

[0003] Such concepts already exist that advantageously implement emergency braking using a parking brake system. In particular, such emergency braking is achieved by venting at least one spring brake cylinder, which results in the application of at least one spring brake cylinder and a corresponding emergency braking.

[0004] For example, DE 10 2019 131 930 A1 describes an electropneumatic parking brake module for an electronically controllable pneumatic brake system for a vehicle, comprising 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 and designed to control a spring-loaded pressure at the parking brake connection as a function of a control pressure, and a pilot valve arrangement receiving the supply pressure for providing the control pressure, wherein the pilot valve arrangement has a holding valve which opens when de-energized and a bistable valve which can be switched between a first ventilation position and a second ventilation position.According to the approach disclosed in DE 10 2019 131 930 A1, the holding valve, which opens without current, can generate a failure braking in the event of a fault or power failure by automatically venting the control pressure.

[0005] DE102019131110A1 relates to a method and a device for the safe emergency stopping of a commercial vehicle with an electronically controllable pneumatic braking system with spring brake cylinders on at least one axle. The electronically controllable pneumatic braking system comprises a service brake system and at least one first redundancy system. In the event of a first fault in the service brake system, the vehicle is braked by the redundancy system. The electronically controllable braking system further comprises an unthrottled venting path and a throttled venting path for venting the spring brake cylinders. The method is characterized by the steps of: determining a second fault in the redundancy system, and in response thereto: automated throttled venting of at least one of the spring brake cylinders via the throttled venting path for slow, safe stopping of the vehicle.

[0006] Restoring a vehicle to a drivable condition after a failure braking operation remains problematic. This typically requires applying emergency release pressure to vent at least one applied spring brake cylinder. Applying emergency release pressure in this manner generally requires a relatively high level of time and / or equipment expenditure, and in particular, manual intervention. It is therefore desirable to improve the release of a parking brake system. In particular, providing emergency release pressure should be possible in a reliable manner and with minimal effort.

[0007] This is where the invention comes in, the object of which is to provide an improved electropneumatic braking system that enables the improved provision of an emergency release pressure.

[0008] The object is achieved by the invention in a first aspect with an electropneumatic braking system of claim 1. The invention is based on an electropneumatic braking system for a vehicle, preferably a commercial vehicle, comprising a parking brake system with a parking brake valve unit which is designed to control a parking brake pressure at at least one spring-loaded connection as a function of a pilot pressure, wherein the parking brake valve unit has a pilot unit which controls the pilot pressure to a pilot path as a function of an electronic parking brake signal. The parking brake valve unit has an additional brake pressure connection which is or can be connected pneumatically to the pilot path for controlling an emergency release pressure, wherein the control of the emergency release pressure at the additional brake pressure connection causes the parking brake pressure to be controlled at at least one spring-loaded connection.The electropneumatic braking system further comprises a first control unit configured to provide the electronic parking brake signal to the parking brake valve unit.

[0009] According to the invention, the electropneumatic braking system is characterized in that it comprises an emergency release valve unit. The emergency release valve unit is configured to receive a service brake pressure provided by a service brake system and effective for service braking, or a pressure derived from the service brake pressure, and to provide an emergency release pressure at the auxiliary brake pressure connection in response to a received electronic emergency release signal.

[0010] The invention is based on the finding that providing an emergency release pressure is advantageous for releasing the spring brake cylinders, particularly when the vehicle is to be moved after a failure braking by the parking brake system. The invention includes the finding that the emergency release pressure can advantageously be provided in an electronically controlled manner by an emergency release valve unit designed to provide emergency release pressure as a function of a received electronic emergency release signal. In this way, the otherwise required manual effort for providing the emergency release pressure to release the spring brake cylinders can be reduced, or preferably even avoided.

[0011] By receiving a service brake pressure effective for service braking or a pressure derived from the service brake pressure and using it to provide the emergency release pressure, a system independent of the parking brake system can be used to provide the emergency release pressure. This is particularly advantageous if the first control unit and / or the parking brake system is unavailable due to a fault or power failure.

[0012] By using the service brake pressure or a pressure derived from the service brake pressure, it is further advantageously achieved that this pressure can only be made available to the emergency release valve unit when the service brake system is also actuated. This advantageously ensures that the parking brake system or the spring brake cylinders are not accidentally released due to a simple malfunction, for example, in a valve of the emergency release valve unit.

[0013] Advantageous further developments of the invention can be found in the dependent claims and specify in detail advantageous possibilities for realizing the concept explained above within the scope of the task and with regard to further advantages.

[0014] Particularly preferably, the service brake pressure or the pressure derived from the service brake pressure is provided as emergency release pressure at the auxiliary brake pressure connection. In other preferred developments, the service brake pressure is provided as emergency release pressure at the auxiliary brake pressure connection by a valve, preferably a pneumatically controlled main valve, controlling a reservoir pressure as an emergency release pressure at the auxiliary brake pressure connection depending on the service brake pressure and / or the electronic emergency release signal.

[0015] In a preferred development, it is provided that the electronic emergency release signal is provided by a further control unit. Preferably, the emergency release valve unit is pneumatically connected or connectable to a service brake system. Particularly preferably, the emergency release valve unit has a service brake connection that can be connected to a part of the service brake system that carries service brake pressure, in particular an axle modulator, for receiving a service brake pressure. Preferably, the additional brake pressure connection is an emergency release connection. In other developments, the brake pressure connection can alternatively be another connection, preferably an anti-compound connection.

[0016] In a preferred embodiment, the additional control unit is a service brake control unit assigned to the service brake system. Such embodiments advantageously ensure that the emergency release valve unit can be activated if the first control unit assigned to the parking brake system has failed. Such a failure of the first control unit can occur, for example, due to a fault and / or a power failure.

[0017] The invention is further developed in that the first control unit is supplied with electrical energy by a first energy supply, and the further control unit is supplied with electrical energy by a second energy supply that is independent of the first energy supply. In such developments, it is advantageously achieved that the emergency release valve unit can still be controlled by the further control unit even if the first energy supply has failed, for example because a fault leading to a power failure has occurred in the first energy supply and the first control unit. Preferably, the first energy supply has a first battery and / or the second energy supply has a second battery. Particularly preferably, the first energy supply is a first battery and / or the second energy supply is a second battery.

[0018] Within the scope of a preferred development, it is provided that the emergency release valve unit has an emergency release pressure sensor which is designed to determine the emergency release pressure provided by the emergency release valve unit. The function of the emergency release valve unit can advantageously be checked by means of an emergency release pressure sensor. Preferably, the emergency release pressure sensor is pneumatically connected to the main connection of the emergency release valve unit and / or to the first emergency release valve connection. Preferably, the emergency release pressure sensor is designed to provide a corresponding emergency release pressure signal, preferably to the further control unit. Preferably, the emergency release pressure sensor is arranged in the emergency release valve unit and / or the emergency release module or the structural unit.

[0019] It is advantageous that the pilot control unit is designed to be pneumatically self-locking. In In a preferred development, the pilot control unit has a compensation valve between a supply path of the parking brake valve unit and the control path, which compensation valve is preferably pneumatically switchable via a compensation control connection which is pneumatically connected to the control path. In In a particularly preferred embodiment, the compensation valve is throttled and has a first throttle between a first compensation valve connection and a second compensation valve connection, and / or a second throttle between the second compensation valve connection and a third compensation valve connection. By means of a pneumatically self-holding pilot control unit, in particular by means of a compensation valve, a control connection of the pneumatically actuated main valve can advantageously be permanently ventilated by a one-time or briefly applied emergency release pressure, since the compensation valve can establish a pneumatic connection between a supply path and the control connection. The compensation valve is preferably switched via a pneumatic compensation control path.In this way, the spring-loaded brake cylinders can be released permanently or over a longer period by briefly applying the emergency release pressure, preferably in the form of a service brake pressure. The pilot control unit preferably has a first pilot control valve configured to controllably pneumatically connect the supply path to the pilot control path. The pilot control unit preferably has a second pilot control valve configured to controllably pneumatically connect the pilot control path to a vent port.

[0020] Within the scope of a preferred development, the emergency release valve unit comprises a 3 / 2-way valve, preferably a 3 / 2-way solenoid valve. The 3 / 2-way valve has a first emergency release valve connection for providing the emergency release pressure, a second emergency release valve connection for receiving the service brake pressure or the pressure derived from the service brake pressure, and a third emergency release vent connection. The 3 / 2-way valve is designed to pneumatically connect the first emergency release valve connection to the second emergency release valve connection in a first emergency release valve position, and to pneumatically connect the first emergency release valve connection to the emergency release vent connection in a second emergency release valve position. The first emergency release valve connection is preferably pneumatically connectable to the additional brake pressure connection. In particular, in the first emergency release valve position, the emergency release vent connection is blocked.In particular, the second emergency release valve connection is blocked in the second emergency release valve position. Particularly preferably, the 3 / 2-way valve is designed as a solenoid valve that can be controlled in response to an electronic emergency release signal.

[0021] The invention is further developed in that the emergency release valve unit has an emergency release pilot arrangement which, depending on the electronic emergency release signal, controls the service brake pressure or the pressure derived from the service brake pressure as the emergency release pilot pressure, and has an emergency release main valve arrangement which, depending on the emergency release pilot pressure, controls a supply pressure as the emergency release pressure at the main connection. Preferably, the emergency release valve unit has a supply connection for receiving the supply pressure. Preferably, the emergency release main valve arrangement has a pneumatically switchable main valve. Preferably, the main valve is designed as a 3 / 2-way valve, with a first main valve connection for providing the emergency release pressure, a second main valve connection for receiving the supply pressure, and a third main valve vent connection.Preferably, the main valve is configured to pneumatically connect the first main valve port to the second main valve port in a first main valve position and particularly preferably to block the main valve vent port. Preferably, the main valve is configured to pneumatically connect the first main valve port to the main valve vent port in a second main valve position and particularly preferably to block the second main valve port.

[0022] The emergency release valve unit preferably has a pneumatic self-holding path that pneumatically connects a main valve control port of the main valve to the main port of the emergency release valve unit and / or a first main valve port of the main valve. By means of the pneumatic self-holding path, the emergency release valve unit can advantageously achieve pneumatic self-holding, through which a briefly applied service brake pressure leads to a permanent provision of an emergency release pressure. In this way, the at least one spring-loaded brake cylinder can be permanently released after a single application of the service brake pressure or the pressure derived from the service brake pressure.

[0023] Preferably, the emergency release pilot control arrangement comprises a pilot valve that can be controlled by the electronic emergency release signal. Particularly preferably, the pilot valve is designed as a 2 / 2-way valve, preferably as a 2 / 2-way solenoid valve.

[0024] The invention is further developed in that the emergency release pilot control arrangement has a holding valve which is designed to selectively hold the emergency release pilot control pressure, in particular at the main valve control connection, as a function of the emergency release signal. The pilot control valve is preferably designed as a 3 / 2-way valve, preferably as a 3 / 2-way solenoid valve. The holding valve is preferably designed as a 2 / 2-way valve, preferably as a 2 / 2-way solenoid valve. The holding valve is preferably arranged and designed to hold the modulated emergency release pilot control pressure at a main valve control connection of the main valve. Particularly preferably, the electronic emergency release signal comprises a first emergency release signal for the pilot control valve and / or a second emergency release signal for the holding valve.

[0025] Within the scope of a preferred further development, it is provided that the emergency release valve unit is arranged in the parking brake valve unit or is combined with the parking brake valve unit to form a structural unit or is designed as an independent emergency release module.

[0026] In a second aspect, the invention further provides a vehicle having an electropneumatic braking system according to the first aspect of the invention, wherein the electropneumatic braking system comprises a service braking system. In a preferred development, the vehicle, preferably the electropneumatic braking system, has a further control unit for providing the electronic emergency release signal.

[0027] In a preferred development, it is provided that the vehicle is a tractor-trailer combination with a towing vehicle designed as a commercial vehicle and a trailer, wherein the electropneumatic braking system has a first emergency release valve unit, which is assigned to a first parking brake valve unit for a towing vehicle parking brake circuit of the towing vehicle and is switchable as a function of an electronic vehicle emergency release signal, and a second emergency release valve unit, which is assigned to a second parking brake valve unit for a trailer parking brake circuit of the trailer and is switchable as a function of an electronic trailer emergency release signal. Particularly preferably, the electronic vehicle emergency release signal and the electronic trailer emergency release signal are provided by the further control unit.

[0028] In a preferred development of the vehicle, it is provided that the first parking brake valve unit and the second parking brake valve unit are designed as a common, multi-channel parking brake valve unit.

[0029] In a third aspect, the invention further provides a method for operating an electropneumatic brake system to achieve the object, comprising the steps of: receiving, by an emergency release valve unit, a service brake pressure effective for service braking or a pressure derived from the service brake pressure; providing an electronic emergency release signal; and receiving the electronic emergency release signal by the emergency release valve unit; providing an emergency release pressure by the emergency release valve unit as a function of the received electronic emergency release signal, which is effective for at least one spring brake cylinder; receiving the emergency release pressure by a parking brake valve unit. In a preferred development of the method, it is provided that the electronic emergency release signal is provided by a further control unit.In a preferred development of the method, the additional control unit is different from a control unit assigned to the parking brake valve unit. In a preferred development of the method, the service brake pressure or the pressure derived from the service brake pressure or a reservoir pressure is provided as the emergency release pressure.

[0030] In a fourth aspect, the invention further provides for the use of an emergency release valve unit in an electropneumatic brake system to achieve the object, wherein the electropneumatic brake system comprises a parking brake system with a parking brake valve unit which is designed to control a parking brake pressure at at least one spring-loaded connection as a function of a pilot pressure, wherein the parking brake valve unit comprises a pilot unit which controls the pilot pressure to a pilot path as a function of an electronic parking brake signal, wherein the parking brake valve unit comprises an additional brake pressure connection which is pneumatically connected or connectable to the pilot path for controlling an emergency release pressure, wherein the control of the emergency release pressure at the additional brake pressure connection causes the parking brake pressure to be controlled at at least one spring-loaded connection, and comprises a first control unit,which is designed to provide the electronic parking brake signal to the parking brake valve unit, wherein the emergency release valve unit receives a service brake pressure provided by a service brake system and effective for service braking, or a pressure derived from the service brake pressure, and provides an emergency release pressure at the additional brake pressure connection depending on a received electronic emergency release signal. In a preferred development of the use, it is provided that the electronic emergency release signal is provided by a further control unit.

[0031] It should be understood that the electropneumatic braking system according to the first aspect of the invention, the vehicle according to the second aspect of the invention, the method for operating an electropneumatic braking system according to the third aspect of the invention, and the use of an emergency release valve unit in an electropneumatic braking system according to the fourth aspect of the invention have the same and similar sub-aspects, as set out in particular in the dependent claims. Therefore, for the development of one aspect of the invention, reference is also made to the developments of the other aspects of the invention.

[0032] Preferably, the electropneumatic braking system within the scope of the method according to the third aspect of the invention and / or within the scope of the use according to the fourth aspect of the invention is designed according to at least one of the above-described preferred developments of an electropneumatic braking system according to the first aspect of the invention.

[0033] Embodiments of the invention will now be described with reference to the drawings. These are not necessarily intended to represent the embodiments to scale; rather, the drawings are schematic and / or slightly distorted where this is useful for explanation. With regard to additions to the teachings immediately apparent from the drawings, reference is made to the relevant prior art. It should be noted that various modifications and changes to the form and detail of an embodiment can be made without departing 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 further developing the invention, both individually and in any combination.Furthermore, all combinations of at least two of the features disclosed in the description, the drawings and / or the claims fall within the scope of the invention. The general idea of ​​the invention is not limited to the exact form or detail of the preferred embodiments shown and described below, or limited to an object that would be limited compared to the object claimed in the claims. In specified dimensioning ranges, values ​​lying within the stated limits are also intended to be disclosed as limit values ​​and to be used and claimed as desired. For the sake of simplicity, the same reference numerals are used below for identical or similar parts or parts with identical or similar functions.

[0034] Further advantages, features and details of the invention will become apparent from the following description of the preferred embodiments and from the drawings, which show: Fig. 1 a vehicle in the form of a commercial vehicle with a preferred embodiment of an electropneumatic braking system, Fig. 2 a first embodiment of an emergency release valve unit for an electropneumatic brake system according to the first aspect of the invention, Fig. 3 a second embodiment of an emergency release valve unit for an electropneumatic brake system according to the first aspect of the invention, Fig. 4 a third embodiment of an emergency release valve unit for an electropneumatic brake system according to the first aspect of the invention, Fig. 5 a fourth embodiment of an emergency release valve unit for an electropneumatic brake system according to the first aspect of the invention, Fig. 6 a first embodiment of a parking brake valve unit for an electropneumatic brake system according to the first aspect of the invention, Fig. 7 a second embodiment of a parking brake valve unit for an electropneumatic brake system according to the first aspect of the invention, and in Fig. 8 a vehicle in the form of a tractor-trailer combination with a further preferred embodiment of an electropneumatic braking system.

[0035] Fig. 1 schematically shows a vehicle 200 in the form of a commercial vehicle 201 with a preferred embodiment of an electropneumatic braking system 202. The electropneumatic braking system 202 has a service braking system 510 and a parking braking system 520. The parking braking system 520 has a parking braking valve unit 24 with at least one spring-loaded connection 21 for providing a parking braking pressure pPB to spring-loaded brake cylinders 442. In the present case, the vehicle 200 has four spring-loaded brake cylinders 442, each assigned to a rear wheel. Furthermore, the service braking system 510 has two service braking cylinders 445, each assigned to a front wheel 221.

[0036] The spring brake cylinders 442 are designed here as combination brake cylinders 446, i.e. they each have a service brake chamber 444 which is assigned to the service brake system 510 and can be actuated by means of a service brake pressure pB.

[0037] To receive the service brake pressure pB, the service brake chambers 444 are each pneumatically connected to a service brake pressure connection 486 of an axle modulator 484. The electropneumatic brake system 202 has a further control unit 420, which is designed as a service brake control unit 421 for controlling the service brake system 510. In the present case, the further control unit 420 is connected to the axle modulator 486 for signal control purposes.

[0038] As shown here, the axis modulator 486 and the further control unit 420 are advantageously structurally integrated into a central module 480.

[0039] The electropneumatic brake system 202 further comprises a parking brake valve unit 24 configured to control the parking brake pressure pPB. To provide the parking brake pressure pPB to the spring brake cylinders 442, the parking brake valve unit 24 has at least one spring brake connection 21 pneumatically connected to the spring brake cylinders 442.

[0040] The electropneumatic brake system 202 has a first control unit 410 which is connected to the parking brake valve unit 24 in a signal-carrying manner for providing an electronic parking brake signal SF for the purpose of control.

[0041] By controlling the parking brake pressure pPB as a function of the electronic parking brake signal SF at the spring brake connection 21, the spring brake cylinders 442 are ventilated, and a wheel brake (not shown here) is released. However, if the spring brake cylinders 442 are vented, i.e., if the parking brake pressure pPB drops below a minimum value, the spring brake cylinders 442 are applied, and the wheels, in this case the rear wheels 222, are braked by the wheel brakes (not shown here).

[0042] Such venting of the spring brake cylinders 442 can occur, in particular, during a failure or emergency braking. Such a case occurs, for example, if an exception error FA or a power failure FS occurs in the first control unit 410. In such a case, the vehicle 200 can no longer be moved easily because the spring brake cylinders 442 are applied and ventilation via the parking brake valve unit 24 is not possible due to the failure of the first control unit 410.

[0043] A power failure FS occurs, for example, when the first control unit 410 is no longer supplied with electrical energy E. In this case, the first control unit 410 is electrically connected to a first power supply 780 for the purpose of supplying electrical energy E. In this case, the further control unit 420 is electrically connected to a second power supply 782 for the purpose of supplying electrical energy E.

[0044] The electropneumatic brake system 202 has an emergency release valve unit 1. The emergency release valve unit 1 is configured to provide an emergency release pressure pN to the parking brake valve unit 24.

[0045] The emergency release valve unit 1 is pneumatically connected via a main connection 26, at which the emergency release pressure pN is controlled, to an additional brake pressure connection 38 in the form of an emergency release connection 84 of the parking brake valve unit 24 for providing the emergency release pressure pN.

[0046] The emergency release valve unit 1 is pneumatically connected to the service brake system 510, in this case to the axle modulator 480, via a service brake connection 27 to receive the service brake pressure pB. In other embodiments, the received pressure can be a pressure pB' derived from the service brake pressure pB.

[0047] The emergency release valve unit 1 is presently connected to the further control unit 420 in a signal-carrying manner for receiving an electronic emergency release signal SN.

[0048] The parking brake valve unit 24 and the first control unit 410 can, as shown here, be structurally integrated as a parking brake module 39.

[0049] The emergency release valve unit 1 and the parking brake module 39 can advantageously be structurally integrated into a single unit 36, as indicated here by dashed lines. In alternative embodiments, the emergency release valve unit 1 can be designed as a structurally independent emergency release module 37.

[0050] Fig. 2 shows a first emergency release valve unit 1 for a preferred embodiment of an electropneumatic brake system. In the present case, the emergency release valve unit 1 has a 3 / 2-way valve 120 in the form of a 3 / 2-way solenoid valve 122. The 3 / 2-way valve 120 has a first emergency release valve connection 120.1, which is pneumatically connected to a main connection 26 for providing the emergency release pressure pN. The 3 / 2-way valve 120 has a second emergency release valve connection 120.2, which is pneumatically connected to a service brake connection 27 for receiving the service brake pressure pB or the pressure pB' derived from the service brake pressure pB. The 3 / 2-way valve 120 has a third emergency release vent connection 120.3, which vents to the environment. In a first emergency release valve position 120A of the 3 / 2-way valve 120, the first emergency release valve connection 120.1 is pneumatically connected to the second emergency release valve connection 120.2 in order to provide a service brake pressure pB provided at the service brake connection 27 as an emergency release pressure pN at the main connection 26. In a second emergency release valve position 120B, the first emergency release valve connection 120.1 is pneumatically connected to the emergency release vent connection 120.3, in particular in order to vent the main connection 26 and connections pneumatically connected thereto.

[0051] By means of a further control unit 420, which can be assigned to a service brake system 510 (not shown here), an electronic emergency release signal SN can be provided at an electronic control connection 120.4 of the 3 / 2-way valve 120 in order to switch the 3 / 2-way valve 120 to the first emergency release valve position 120. In the non-activated state, i.e., when no electronic emergency release signal SN is present at the control connection 120.4, the 3 / 2-way valve 120 is in the second emergency release valve position 120B.

[0052] Fig. 3 shows a second preferred embodiment of an emergency release valve unit 1. In contrast to the one shown in Fig. 2 In the first embodiments of the emergency release valve unit 1 shown, the second emergency release valve unit 1 has an emergency release pressure sensor 94, which is pneumatically connected to the main connection 26. The emergency release pressure sensor 94 is designed to determine the emergency release pressure pN output at the first emergency release valve connection 120.1 and, depending on the determined emergency release pressure pN, to provide a corresponding electronic emergency release pressure signal SPN. In the present case, the emergency release pressure sensor 94 is connected to the further control unit 420 in a signal-carrying manner in order to provide the electronic emergency release pressure signal SPN to the further control unit 420.

[0053] In embodiments with an emergency release pressure sensor 94, the function of the emergency release valve unit 1, in particular the 3 / 2-way valve 120, can advantageously be controlled.

[0054] Fig. 4 shows a third preferred embodiment of an emergency release valve unit 1. In contrast to the one shown in Fig. 3 In the second embodiment of the emergency release valve unit 1 shown here, the emergency release valve unit 1 shown here has an emergency release pilot control arrangement 130 and an emergency release main valve arrangement 140. The emergency release pilot control arrangement 130 comprises a pilot valve 132, which is arranged in an emergency release pilot control path 131 and is designed here as a 2 / 2-way valve 133 in the form of a 2 / 2-way solenoid valve 134. The pilot valve 132 is controllable via an electronic emergency release signal SN. The emergency release main valve arrangement 140 comprises a pneumatically switchable main valve 142, which is designed as a 3 / 2-way valve 143. The pneumatically switchable main valve 142 has a main valve control port 142.4, which is pneumatically connected to the emergency release pilot path 131 for receiving an emergency release pilot pressure pNV. The pilot valve 132 is arranged in the emergency release pilot path 131 between the service brake port 27 and the main valve control port 142.4.

[0055] In In a first valve position 132A of the pilot valve 132, a second pilot valve connection 132.2 connected to the service brake connection 27 is pneumatically connected to a first pilot valve connection 132.1 connected to the main valve control connection 142.4 in order to provide the service brake pressure pB as emergency release pilot pressure pNV at the main valve control connection 142.4. In In a second valve position 132B of the pilot valve 132, the service brake port 27 is pneumatically separated from the main valve control port 142.4. The pilot valve 132 is configured to switch to the first valve position 132A depending on the electronic emergency release signal SN.

[0056] The emergency release valve unit 1 additionally has a supply connection 29 for receiving a supply pressure pV.

[0057] The emergency release main valve arrangement 140 has a main path 141 that pneumatically connects the supply port 29 to the main port 26 and in which the main valve 142 is arranged. The main valve 142 is embodied here as a 3 / 2-way valve 143. The main valve 142 comprises a first main valve port 142.1, which is pneumatically connected to the main port 26 to provide the emergency release pressure pN. The main valve 142 comprises a second main valve port 142.2, which is pneumatically connected to the supply port 29 to receive the supply pressure pV. The main valve 142 comprises a third main valve vent port 142.3, which vents to the environment. In a first main valve valve position 142A of the main valve 142, the first main valve connection 142.1 is pneumatically connected to the second main valve connection 142.2, and preferably the main valve vent connection 142.3 is blocked.In the first main valve position 142A, the supply pressure pV is thus provided as emergency release pressure pN at the main connection 26.

[0058] In a second main valve position 142B of the main valve 140, the first main valve port 142.1 is pneumatically connected to the main valve vent port 142.3, and preferably the second main valve port 142.2 is blocked. Consequently, in the second main valve position 142B, the supply port 29 is pneumatically separated from the main port 26.

[0059] The main valve 142 is pneumatically controllable via the pilot valve 132 such that when an emergency release pilot pressure pNV is applied to the main valve control port 142.4 by the pilot valve 132 in its first valve position 132A, the main valve 142 switches to the first main valve switching position 142A.

[0060] The emergency release valve unit 1 further comprises a pneumatic self-holding path 150, which pneumatically connects the first main valve connection 142.1 to the main valve control connection 142.4. By means of the pneumatic self-holding path 150, the emergency release pressure pN output by the main valve 142 at the first main valve connection 142.1 can advantageously be provided as the emergency release pilot pressure pNV at the main valve control connection 142.4, advantageously independently of the service brake pressure pB provided at the service brake connection 27. With a pneumatic self-holding path 150, it is advantageously possible, upon a one-time, in particular brief, provision of the service brake pressure pB at the main valve control connection 142.4, to subsequently permanently control the emergency release pressure pN at the main connection, even if the service brake pressure pB is no longer provided.

[0061] In Fig. 5 A further preferred, fourth embodiment of an emergency release valve unit 1 is shown. The emergency release valve unit 1 differs from the one shown in Fig. 4 illustrated emergency release valve unit 1 in that the emergency release pilot control arrangement 130 has a further pilot valve 132' in the form of a 3 / 2-way valve 135 and additionally a holding valve 137. The further pilot valve 132' and the holding valve 137 are pneumatically arranged in series in the emergency release pilot control path 131. The further pilot valve 132' is in the form of a 3 / 2-way solenoid valve 136 and can be controlled via a first electronic emergency release signal SN1. The further pilot valve 132' has, in contrast to the Fig. 4 The pilot valve 132 shown additionally has a vent connection 132.3 which is pneumatically connected to the first pilot valve connection 132.1 in the first valve position 132A.

[0062] The holding valve 137 is presently in the form of a 2 / 2-way valve 138, namely a 2 / 2-way solenoid valve 139, and is controllable via a second electronic emergency release signal SN2. The holding valve 137 has a first valve position 137A, in which the holding valve 137 is pneumatically open, i.e., it pneumatically connects the main valve control port 142.4 to the pilot valve 132. The holding valve 137 has a second valve position 137B, in which the holding valve 137 pneumatically separates the main valve control port 142.4 from the pilot valve 132.

[0063] By means of the emergency release pilot control arrangement 130 shown here with a pilot control valve 132 designed as a 3 / 2-way valve 135 and a holding valve 137, an emergency release pilot control pressure pNV applied to the main valve control connection 142.4 can advantageously be controllably vented in order to terminate the modulation of the emergency release pressure pN at the main connection 26. For this purpose, the holding valve 137 is advantageously switched to the first valve position 137A and the pilot control valve 132 to the second valve position 132B so that the main valve control connection 142.4 is vented via the vent connection 132.3.

[0064] Emergency release valve units 1 supplied by a supply pressure pV, in particular those in Fig. 4 shown, third emergency release valve unit 1 and the one in Fig. 5 The fourth emergency release valve unit 1 shown advantageously enables a permanent control of an emergency release pressure pN, in particular even when the service brake pressure pB is no longer present at the service brake connection 27.

[0065] According to the Fig. 4 und Fig. 5 In the emergency release valve units 1 shown, the service brake pressure pB is not provided directly as the emergency release pressure pN, but rather a pressure pB' derived from the service brake pressure pB in the form of the reservoir pressure pV, which is provided as a function of the service brake pressure pB output at the service brake connection 27.

[0066] Fig. 6 shows a preferred parking brake valve unit 24 for an electropneumatic brake system 202. An emergency release valve unit 1, here the one in Fig. 3 The second embodiment of an emergency release valve unit 1 shown is connected via its main connection 26 for providing the emergency release pressure pN to an additional brake pressure connection 38 of the parking brake valve unit 24. The additional brake pressure connection 38 is designed here as an emergency release connection 84.

[0067] The parking brake valve unit 24 has a supply pressure path 70. The parking brake valve unit 24 is designed to control a parking brake pressure pBP at at least one spring-loaded connection 21 as a function of an electronic parking brake signal SF.

[0068] The supply pressure path 70 is pneumatically connected to a first compressed air supply 6 and a second compressed air supply 7 via a supply shuttle valve 49 to receive a supply pressure pV. The supply shuttle valve 49 is designed as a select-high shuttle valve, so that the one of the first compressed air supply 6 and the second compressed air supply 7 is connected to the supply pressure path 70 in which the higher supply pressure pV prevails, and the other compressed air supply 6, 7 is blocked.

[0069] The supply pressure path 70 is divided into a supply branch 74, a control branch 76, and a compensation path 86. The compensation path 86 pneumatically connects the supply pressure path 70 to a pilot control path 47.

[0070] A compensation valve 80 is arranged in the compensation path 86. The compensation valve 80 is designed as a 3 / 2-way valve 81. The compensation valve 80 has a first compensation valve connection 80.1, which is pneumatically connected to the supply pressure path 70. The compensation valve 80 has a second compensation valve connection 80.2, which is pneumatically connected to the compensation path 86. The compensation valve 80 has a third compensation valve connection 80.3, which is pneumatically connected to a vent line 44. The vent line 44 is connected to a vent connection 3, which vents to the environment.

[0071] The compensation valve 80 has a compensation valve control port 80.4, which is pneumatically connected to the second compensation valve port 80.2 via a compensation control path 83. Pneumatic control is preferably implemented via the compensation control path 83. A pressure present at the second compensation valve port 80.2, in particular a pilot pressure pSV, is provided to the compensation valve control port 80.4 via the compensation control path 83.

[0072] In a second switching position 80B of the compensation valve 80, the first compensation valve connection 80.1 is pneumatically connected to the second compensation valve connection 80.2, and preferably the third compensation valve connection 80.3 is blocked. In the second switching position 80B, the supply pressure path 70 is thus pneumatically connected to the compensation path 86 and thus to the pilot control path 47. In a first switching position 80A of the compensation valve 80, the second compensation valve connection 80.2 is pneumatically connected to the third compensation valve connection 80.3, and preferably the first compensation valve connection 80.1 is blocked. In the first switching position 80A, the compensation path 86 and thus the pilot control path 47 are thus pneumatically connected to the vent connection 3.

[0073] In the present case, the compensation valve 80 has a first throttle 67 between the first compensation valve connection 80.1 and the second compensation valve connection 80.2. The first throttle 67 advantageously has a nominal diameter that is smaller than the compensation path 86 and / or the supply pressure path 70. In the present case, the compensation valve 80 has a second throttle 68 between the second compensation valve connection 80.2 and the third compensation valve connection 80.3. The second throttle 68 advantageously has a nominal diameter that is smaller than the compensation path 86 and / or the vent line 44.

[0074] When the compensation valve 80 is switched to the second switching position 80B via the compensation control path 83, the supply pressure pV is provided to the compensation valve control port 80.4 via the compensation control path 83 in order to hold the compensation valve 80 in the second switching position 80B. In this state, an emergency release pressure pN or pilot control pressure pSV, which is applied once via the additional brake pressure port 38 and held in the pilot control path 47 by the check valve 85, is maintained. If a pressure drop should occur due to leaks in the pilot control path 47, the supply pressure pV is adjusted in a compensating manner via the compensation valve 80, in particular via the throttle 27.

[0075] In the present case, the parking brake valve unit 24 has a main valve unit 34. The main valve unit 34 comprises a pilot control unit 8 and a pneumatically actuated main valve 18. The pilot control unit 8 is designed to provide a pilot pressure pSV at a control port 18.3 of the pneumatically actuated main valve 18 as a function of the electronic parking brake signal SF. The pneumatically actuated main valve 18 is designed to control the parking brake pressure pBP, which is provided at the spring-loaded port 21, at a main port 18.2 as a function of this parking brake control pressure pPS. The pneumatically actuated main valve 18 is designed here as a relay valve 20.

[0076] The pilot control unit 8 has a first pilot valve 41 and a second pilot valve 42, each designed as a 2 / 2-way solenoid valve. By means of the first pilot valve 41, in an open position 41A, the supply pressure pV from the supply pressure path 70 can be provided to the pilot control path 47 as pilot pressure pSV. The pilot control path 47 is arranged between the first pilot valve 41 and the second pilot valve 42 and is or can be pneumatically connected to the control port 18.3 of the main valve 18. By means of the second pilot valve 42, the pilot pressure pSV can be maintained in the pilot control path 47, or the pilot control path 47 can be vented in a controllable manner.

[0077] By switching the first pilot valve 41 to a blocking position 41B, the pilot pressure pSV can be captured or held in the pilot path 47, in particular at the control port 18.3, for permanent actuation. The second pilot valve 42 is also in a blocking position 42B. Corresponding to the design of the pilot unit 8 with a first pilot valve 41 and a second pilot valve 42, the electronic parking brake signal SF comprises a first electronic parking brake signal SF1 for controlling the first pilot valve 41 and a second electronic parking brake signal SF2 for controlling the second pilot valve 42. By switching the second pilot valve 42 to an open position 42A, the pilot path 47 can be pneumatically connected to the vent line 44 to vent the control port 18.3.

[0078] The pilot control path 47 is additionally pneumatically connectable to an auxiliary brake pressure connection 38 and / or to an anti-compound connection 82. By means of the auxiliary brake pressure connection 38, the emergency release pressure pN can be provided to the pilot control path 47 and in particular to the control connection 18.3 in order to control a parking brake pressure pBP at the spring brake connection 21 independently of the pilot control unit 8. In particular, by means of the auxiliary brake pressure connection 38, the mobility of the commercial vehicle 201 can be restored in a controlled manner in the event of a failure of the brake system 202 or a similar fault that leads to venting of the spring brake cylinders 442. Advantageously, a check valve 85 is arranged at the auxiliary brake pressure connection 38, which opens in the direction of the control connection 18.3 and closes in the opposite direction.By means of the check valve 85, an uncontrolled escape of the pilot pressure pSV via the additional brake pressure connection 38 can advantageously be prevented. Also, by means of the check valve 85, a once-activated emergency release pressure pN can be permanently captured or held in the pilot path 47 for the permanent ventilation of the spring-loaded connection 21 and thus for the release of at least one parking brake cylinder.

[0079] By means of the anti-compound connection 82, an additional parking brake pressure pSZ can be provided to the pilot control path 47 and in particular to the control connection 18.3 in order to control a parking brake pressure pBP at the spring-loaded connection 21 independently of the pilot control unit 8. In particular, the additional parking brake pressure pSZ can be provided by a service brake function (not shown here) in order to implement an anti-compound function.

[0080] The electropneumatic valve arrangement 1 further advantageously has a selector valve 88 arranged in the pilot control path 47, which is designed as a select-high valve. The selector valve 88 has a first selector valve connection 88.1 connected to the anti-compound connection 82, a second selector valve connection 88.2 connected to the auxiliary brake pressure connection 38, and a third selector valve connection 88.3 connected to the control connection 18.3. The selector valve 88 is designed to connect the one of the first selector valve connection 88.1 and the second selector valve connection 88.2 to which the higher pressure is applied to the third selector valve connection 88.3.

[0081] The electropneumatic valve arrangement 1 has a pressure sensor 64 which is pneumatically connected to the spring-loaded connection 21 for determining the parking brake pressure pBP.

[0082] The electropneumatic valve assembly 1 has an electronic control unit 99, which is connected to the electronic components of the electropneumatic valve assembly 1 in a signal- and / or power-carrying manner. In particular, the first pilot valve 41 and the second pilot valve 42 are electrically connected to the electronic control unit 99 for control. The pressure sensor 64 is also electrically connected to the electronic control unit 99.

[0083] Such a parking brake valve unit 24 as shown here is particularly preferably suitable for use with the first emergency release valve unit 1 or the second emergency release valve unit 1, since due to the compensation valve 80 a parking brake pressure pB which is controlled once as an emergency release pressure pN leads to a permanent control of a parking brake pressure pPB at the spring-loaded connection 21.

[0084] Fig. 7 shows a second parking brake valve unit 24. The second parking brake valve unit 24, in contrast to the first parking brake valve unit 24, does not have a compensation valve 80 and has a further pilot control unit 8' with a further pilot control path 47'. The further pilot control unit 8' differs from the one in Fig. 6 The pilot control unit 8 shown is distinguished by the fact that it has a bistable valve 72, via which both the ventilation and the venting of the further pilot control path 47' takes place. The further pilot control unit 8' further has a pilot control holding valve 76, which is pneumatically connected in series with the bistable valve 72 in the further pilot control path 47'. With the pilot control holding valve 76, the pilot control pressure pSV can be held at the control connection 18.3 of the pneumatically actuated main valve 18.

[0085] The second parking brake valve unit 24 is preferably suitable for use with an emergency release valve unit 1 that enables permanent control of an emergency release pressure pN, particularly preferably with the third emergency release valve unit 1 or the fourth emergency release valve unit 1. Since the second parking brake valve unit 24 does not have a compensation valve 80 or similar pneumatic holding function, an emergency release valve unit 1 with a self-holding path 150 can advantageously provide this pneumatic holding function instead.

[0086] Fig. 8 shows a vehicle 200 in the form of a tractor unit 206 with a towing vehicle 203 designed as a commercial vehicle 201 and a trailer 204 pulled by it.

[0087] The vehicle 200 has an electropneumatic braking system 202 according to the invention, with a first emergency release valve unit 1.1 assigned to a first parking brake valve unit 24.1, and a second emergency release valve unit 1.2 assigned to a second parking brake valve unit 24.2. The first parking brake valve unit 24.1 is assigned to a first number M1 of spring-loaded brake cylinders 442 arranged in the towing vehicle 203 and is pneumatically connected thereto via a towing vehicle parking brake circuit 240. The second parking brake valve unit 24.2 is assigned to a second number (two) of spring-loaded brake cylinders 442 arranged in the trailer 204 and is pneumatically connected thereto via a trailer parking brake circuit 242.

[0088] The first parking brake valve unit 24.1 and the second parking brake valve unit 24.2 are each connected in a signal-carrying manner to a first control unit 410, which is assigned to the parking brake system 520.

[0089] In preferred embodiments, the first parking brake valve unit 24.1 and the second parking brake valve unit 24.2, as indicated here by dashed lines, are designed as a common, multi-channel parking brake valve unit 24.3

[0090] The emergency release valve units 1.1, 1.2 are each signal-carryingly connected to a further control unit 420, which in this case is assigned to a service brake system 510. The further control unit 420 is configured to provide an electronic vehicle emergency release signal SNA to the first parking brake valve unit 24.1. The further control unit 420 is further configured to provide an electronic trailer emergency release signal SNB to the second parking brake valve unit 24.2. By providing the electronic vehicle emergency release signal SNA and the electronic trailer emergency release signal SNB, all spring brake cylinders 442 can be released and a driveable state of the vehicle 200 can be established. List of reference symbols (part of the description)

[0091] 1 Emergency release valve unit 1.1, 1.2 First, second emergency release valve unit 3 Vent connection 6 First compressed air supply 7 Second compressed air supply 8, 8 Pilot control unit 18 Main valve 18.2 Second main connection 18.3 Main valve control connection 20 Relay valve 21 Spring-loaded connection 24 Parking brake valve unit 24.1, 24.2 First, second parking brake valve unit 26 Main connection of the emergency release valve unit 27 Service brake connection of the emergency release valve unit 24.3 Common parking brake valve unit 29 Supply connection of the emergency release valve unit 34 Main valve unit 36 ​​Assembly unit 37 Emergency release module 38 Additional brake pressure connection 39 Parking brake module 41 First pilot control valve 41A Open position of the first pilot valve 41B Blocking position of the first pilot valve 42 Second pilot valve 42A Open position of the second pilot valve 42B Blocking position of the second pilot valve 44 Vent line 47, 47' Pilot path 49 Supply shuttle valve 64 Pressure sensor 67 First throttle 68 Second throttle70Supply pressure path 72Bistable valve 74Supply branch 76Control branch 80Compensation valve 80AFirst switching position of the compensation valve 80BSecond switching position of the compensation valve 80.1First compensation valve connection 80.2Second compensation valve connection 80.3Third compensation valve connection 813 / 2-way valve 82Anti-compound connection 83Compensation control path 84Emergency release connection 80.4Compensation valve control connection 85Check valve 86Compensation path 88Selector valve 88.1First selection valve connection 88.2Second selection valve connection 88.3Third selection valve connection 94Emergency release pressure sensor 99Electronic control unit 1203 / 2-way valve 120AFirst Emergency release valve position of the 3 / 2-way valve 120B Second emergency release valve position of the 3 / 2-way valve 120.1 First emergency release valve connection of the 3 / 2-way valve 120.2 Second emergency release valve connection of the 3 / 2-way valve 120.3 Emergency release vent connection of the 3 / 2-way valve 120.4 Control connection of the 3 / 2-way valve1223 / 2-way solenoid valve 130Emergency release pilot control arrangement 131Emergency release pilot control path of the emergency release pilot control arrangement 132Pilot valve of the emergency release pilot control arrangement 132AFirst valve position of the pilot control valve 132BSecond valve position of the pilot control valve 132.1First pilot control valve connection 132.2Second pilot control valve connection 132.3Vent connection of the pilot control valve 1332 / 2-way valve, pilot control valve designed as a 2 / 2-way valve 1342 / 2-way solenoid valve, pilot control valve designed as a 2 / 2-way solenoid valve 1353 / 2-way valve, pilot control valve designed as a 3 / 2-way valve 1363 / 2-way solenoid valve, pilot control valve designed as a 3 / 2-way solenoid valve 137 Holding valve 137A First valve position of the holding valve 137B Second valve position of the holding valve 138 2 / 2-way valve, holding valve designed as a 2 / 2-way valve 139 2 / 2-way solenoid valve, holding valve designed as a 2 / 2-way solenoid valve 140 Emergency release main valve arrangement 141 Main path of the emergency release main valve arrangement142 Main valve of the emergency release main valve arrangement 142A First main valve valve position 142B Second main valve valve position 142.1 First main valve connection 142.2 Second main valve connection 142.3 Main valve vent connection 142.4 Main valve control connection 143 3 / 2-way valve, main valve designed as a 3 / 2-way valve 150 Self-holding path, self-holding path of the emergency release main valve arrangement 200 Vehicle 201 Commercial vehicle 202 Electro-pneumatic braking system 203 Towing vehicle 204 Trailer 206 Tractor / trailer combination 221 Front wheel 222 Rear wheel 240 Towing vehicle parking brake circuit 242 Trailer parking brake circuit 410 First control unit 420 Further control unit 421 Service brake control unit 442 Spring brake cylinder 444Service brake chamber 445Service brake cylinder 446Combination brake cylinder 480Central module 484Axle modulator 486Service brake pressure connection 510Service brake system 520Parking brake system 780First energy supply 782Second energy supply EEnergy FAException error FSPower failure M1, M2First, secondNumber of spring brake cylinders pBService brake pressure pNemergency release pressure pNVemergency release pilot pressure pPBParking brake pressure pSVPilot pressure pSZAuxiliary parking brake pressure pVReservoir pressure SVehicle emergency release signal SFElectronic parking brake signal SF1, SF2First, second electronic parking brake signal SNElectronic emergency release signal SN1, SN2First, second electronic emergency release signal SNAVehicle emergency release signal SNTBrailer emergency release signal SPNEmergency release pressure signal

Claims

1. Electropneumatic brake system (202) for a vehicle (200), preferably a commercial vehicle (201), comprising: a parking brake system (520) which has a parking brake valve unit (24) designed to adjust a parking brake pressure (pPB) at at least one spring-loaded connection (21) on the basis of a pilot control pressure (pSV), wherein the parking brake valve unit (24) comprises a pilot control unit (8) which, on the basis of an electronic parking brake signal (SF), adjusts the pilot control pressure (pSV) on a pilot control path (47), wherein the parking brake valve unit (24) has an additional brake pressure connection (38) which is pneumatically connected or connectable to the pilot control path (47) for introducing an emergency-release pressure (pN), wherein the introduction of the emergency-release pressure (pN) at the additional brake pressure connection (38) effects the adjustment of the parking brake pressure (pPB) at at least one spring-loaded connection (21), and a first control unit (410) designed to provide the electronic parking brake signal (SF) to the parking brake valve unit (24), characterized by an emergency-release valve unit (1) which is designed to receive a service brake pressure (pB), provided by a service brake system (510) and effective for a service braking process (BB), or a pressure (pB') derived from the service brake pressure (pB), and to provide an emergency-release pressure (pN) at the additional brake pressure connection (38) on the basis of a received electronic emergency-release signal (SN).

2. Electropneumatic brake system (202) according to claim 1, characterized in that the electronic emergency-release signal (SN) is provided by a further control unit (420).

3. Electropneumatic brake system (202) according to claim 2, characterized in that the further control unit (420) is a service brake control unit (421) assigned to the service brake system (510).

4. Electropneumatic brake system (202) according to claim 2 or 3, characterized in that the first control unit (410) is supplied with electrical energy (E) by a first energy supply (780), and the further control unit (420) is supplied with electrical energy (E) by a second energy supply (782) which is independent of the first energy supply (780).

5. Electropneumatic brake system (202) according to any of the preceding claims, characterized by an emergency-release pressure sensor (94) which is designed to determine the emergency-release pressure (pN) provided by the emergency-release valve unit (1).

6. Electropneumatic brake system (202) according to any of the preceding claims, characterized in that the pilot control unit (8) is designed to be pneumatically self-holding.

7. Electropneumatic brake system (202) according to any of the preceding claims, characterized in that the emergency-release valve unit (1) comprises a 3 / 2-way valve (120), preferably a 3 / 2-way solenoid valve (122), which has a first emergency-release valve connection (120.1) for providing the emergency-release pressure (pN), a second emergency-release valve connection (120.2) for receiving the service brake pressure (pB) or the pressure (pB') derived from the service brake pressure (pB), and a third emergency-release ventilation connection (120.3), wherein, in a first emergency-release valve position (120A), the 3 / 2-way valve (120) pneumatically connects the first emergency-release valve connection (120.1) to the second emergency-release valve connection (120.2), and, in a second emergency-release valve position (120B), pneumatically connects the first emergency-release valve connection (120.1) to the emergency-release ventilation connection (120.3).

8. Electropneumatic brake system (202) according to any of claims 1 to 6, characterized in that the emergency-release valve unit (1) comprises an emergency-release pilot control arrangement (130) which, on the basis of the electronic emergency-release signal (SN), adjusts the service brake pressure (pB) or the pressure (pB') derived from the service brake pressure (pB) as emergency-release pilot control pressure (pNV), and comprises an emergency-release main valve arrangement (140) which has a pneumatically switchable main valve (142) and which, on the basis of the emergency-release pilot control pressure (pNV), adjusts a supply pressure (pV) as the emergency-release pressure (pN) at the main connection (26).

9. Electropneumatic brake system (202) according to claim 8, characterized in that the emergency-release valve unit (1) comprises a pneumatic self-holding path (150) which pneumatically connects a main valve control connection (142.4) of the main valve (142) to the main connection (26) and / or a first main valve connection (142.1) of the main valve (142).

10. Electropneumatic brake system (202) according to claim 8 or 9, characterized in that the emergency-release pilot control arrangement (130) comprises a pilot control valve (132) which can be controlled by means of the electronic emergency-release signal (SN).

11. Electropneumatic brake system (202) according to any of claims 8 to 10, characterized in that the emergency-release pilot control arrangement (130) comprises a holding valve (137) which is designed to selectively hold the emergency-release pilot control pressure (pNV) on the basis of the emergency-release signal (SN).

12. Electropneumatic brake system (202) according to any of the preceding claims, characterized in that the emergency-release valve unit (1) is arranged in the parking brake valve unit (24), or is combined with the parking brake valve unit (24) to form a modular unit (36), or is designed as an independent emergency-release module (23).

13. Vehicle (200), preferably commercial vehicle (201), comprising an electropneumatic brake system (202) according to any of the preceding claims, wherein the electropneumatic brake system (202) comprises a service brake system (510).

14. Vehicle (200) according to claim 13, wherein the vehicle (200) is a tractor arrangement (206) which has a towing vehicle (203), in the form of a commercial vehicle (201), and a trailer (204), characterized in that the electropneumatic brake system (202) comprises a first emergency-release valve unit (1.1) which is assigned to a first parking brake valve unit (24.1) for a towing vehicle parking brake circuit (220) of the towing vehicle (203) and is switchable on the basis of an electronic vehicle emergency-release signal (SNA), and comprises a second emergency-release valve unit (1.2) which is assigned to a second parking brake valve unit (24.2) for a trailer parking-brake circuit (222) of the trailer (204) and is switchable on the basis of an electronic trailer emergency-release signal (SNB).

15. Method for operating an electropneumatic brake system (202) comprising an emergency-release valve unit (1) according to any of claims 1 to 12, comprising the steps of: receiving, via the emergency-release valve unit (1), a service brake pressure (pB) effective for a service brake (BB) or a pressure (pB') derived from the service brake pressure (pB), providing an electronic emergency-release signal (SN), and receiving the electronic emergency-release signal (SN) via the emergency-release valve unit (1), providing an emergency-release pressure (pN) via the emergency-release valve unit (1) on the basis of the received electronic emergency-release signal (SN), which pressure is effective for at least one spring-loaded brake cylinder (442), receiving the emergency-release pressure (pN) via a parking brake valve unit (24).

16. Use of an emergency-release valve unit (1) in an electropneumatic brake system (202), wherein the electropneumatic brake system (202) comprises a parking brake system (520) having a parking brake valve unit (24) which is designed to adjust a parking brake pressure (pPB) at at least one spring-loaded connection (21) on the basis of a pilot control pressure (pSV), wherein the parking brake valve unit (24) comprises a pilot control unit (8) which, on the basis of an electronic parking brake signal (SF), adjusts the pilot control pressure (pSV) on a pilot control path (47), wherein the parking brake valve unit (24) comprises an additional brake pressure connection (38) which is pneumatically connected or connectable to the pilot control path (47) for introducing an emergency-release pressure (pN), wherein the introduction of the emergency-release pressure (pN) at the additional brake pressure connection (38) effects the adjustment of the parking brake pressure (pPB) at at least one spring-loaded connection (21), and comprises a first control unit (410) which is designed to provide the electronic parking brake signal (SF) to the parking brake valve unit (24), wherein the emergency-release valve unit (1) receives a service brake pressure (pB) which is provided by a service brake system (510) and is effective for a service brake (BB), or a pressure (pB') derived from the service brake pressure (pB) and, on the basis of a received electronic emergency-release signal (SN), provides an emergency-release pressure (pN) at the additional brake pressure connection (38).