Electro-Pneumatic Brake Device with Automatic Ventilation of the Spring Brake

An electropneumatic brake device of a motor vehicle, comprising:

• a) an electropneumatic parking brake circuit having spring-loaded brake cylinders and a parking brake control device with a pneumatic control connection, wherein the parking brake control device is configured to release the spring-loaded brake cylinders when the pneumatic control connection is aerated and to apply the spring-loaded brake cylinders when the pneumatic control connection is ventilated;
• b) at least one service brake circuit that comprises service brake cylinders that consume compressed air, and at least one compressed air reservoir at reservoir pressure that provides the compressed air for the service brake cylinders;
• c) an electropneumatic first valve device that is controlled by an electronic controller by way of a signal and is configured, based on the signal of the electronic controller, to remove compressed air from the at least one compressed air reservoir and to supply the compressed air to the service brake cylinders, a pressure sink and/or a compressed air consumer;
• d) a pneumatically controllable second valve device that is configured to connect the pneumatic control connection of the parking brake control device to a pressure sink in at least a first switching position,
• e) wherein the pneumatically controllable second valve device is controlled directly or indirectly by the reservoir pressure prevailing in the at least one compressed air reservoir such that the second valve device second valve device assumes the first switching position when the reservoir pressure falls below a reservoir pressure limit value, and
• f) the electronic controller is configured to automatically generate the signal independently of a driver of the motor vehicle actuating the at least one service brake circuit.