A pneumatic brake system (110) for a commercial vehicle (1) has one spring brake (27), a protection valve (56), a parking brake unit (30), a network of pipelines (40), at least a first (4) and a second (5) tank with compressed air and a relay valve (19) for the parking brake unit (30). A first subnetwork of pipelines (40a) comprises pipelines configured to be pressurized at all times. A second subnetwork of pipelines (40b) comprises at least one pipeline configured to be non-pressurized when the parking brake function is applied. The first subnetwork (40a) comprises pipelines establishing fluid communication between the tanks (4, 5) and the parking brake unit (30), wherein the direction of air flow in these pipelines is by at least one thereto associated valve (50). A method for managing an air flow to an air-actuated spring brake (27) of a pneumatic brake system (110) is disclosed.

A control valve for automatic compressed-air brakes forms a brake cylinder pressure in at least one connected brake cylinder in accordance with a pressure difference between a pressure in a continuous main air line of a train and a stored reference pressure, which is drawn from the pressure of the main air line, comprising valve means for drawing a control pressure from the pressure of the main air line in order to produce a brake cylinder pressure for applying to the brake cylinder. A first piston system provides the control pressure from the pressure of the main air line and a valve mechanism for producing the brake cylinder pressure, wherein a short-stroke first piston system actuates the accelerating element in the same valve housing interacts with a second piston system for actuating the valve mechanism, the second piston system being of longer stroke in relation to the first piston system.

An electronically controllable pneumatic brake system in a vehicle includes wheel brakes for braking respective wheels of the vehicle. Wheel brakes of at least one vehicle axle include spring-loaded cylinders for implementing a pneumatic parking brake in a parking brake braking circuit of the vehicle. The brake system further includes an electronically controllable monostable bypass valve, wherein the monostable bypass valve is disposed between a manually operated parking brake valve and the spring-loaded cylinders. The monostable bypass valve controls, in a first switching position, a bypass control pressure based on an actuation pressure produced by the parking brake valve to implement a manually specified parking brake force. The monostable bypass valve further controls, in a second switching position, a bypass control pressure depending on a venting pressure prevailing in a bypass vent connection to implement an electrically specified parking brake force.

An automatic braking system and method are provided for controlling the automatic operation of a pneumatic (air) brake system installed on commercial highway vehicles and the like, particular heavy trucks and buses. When a possible collision is detected or an object is detected in proximity to at least one side and/or end of the vehicle, the system automatically operates the existing, factory installed air braking system of the vehicle to avoid a collision or mitigate the collision impact by concurrently pressurizing each of the rear and front pneumatic service brakes of the vehicle. Pressing the existing vehicle brake pedal deactivates the automatic braking system, thereby permitting the driver to take over control of braking at any time.

In order to provide a pneumatic system for motor vehicles, which system is lightweight and environmentally friendly and furthermore flexible with respect to further developments and adaptations to modern vehicle systems, the invention proposes a pneumatic system for motor vehicles, comprising at least one compressed air reservoir, a compressor, a valve unit that can be controlled by a control unit and a pipe system, in order to supply compressed air that has been generated by means of the compressor and stored in the compressed air reservoir to an operable actuator.

An electropneumatic parking brake device is for supplying air to and exhausting air from spring-loaded accumulator brake cylinders of an electronically controllable pneumatic braking system for a vehicle and includes a parking brake valve unit with a reservoir port for receiving reservoir pressure from a parking brake reservoir. The parking brake valve unit sets a parking brake pressure at a spring-loaded accumulator port depending on a parking brake signal. A non-return valve is arranged between the parking brake valve unit and the parking brake reservoir to prevent compressed air from flowing back from the parking brake valve unit to the reservoir. A bypass valve is provided which can be switched to supply air to and exhaust it from the spring-loaded accumulator port. The bypass valve is activated and switched independently of the parking brake valve unit.

When a brake system on a commercial vehicle, lateral acceleration and/or yaw of the vehicle are monitored and compared to a first predetermined threshold. If the first predetermined threshold is exceeded, a precharge command is sent to the brake system to precharge one or more air chambers by temporarily deactivating a modulator valve and activating an antilock traction relay valve in order to charge the air chambers up to a level permitted by the modulator valve. Upon detecting a panic braking event, a command signal is sent to the brake system to release the precharged air to facilitate braking.

A control valve includes a diaphragm with a flow path with a predetermined cross-section from a brake pipe to a first side of the diaphragm and another flow path having another predetermined cross-section from a second side of the diaphragm to atmosphere. A dump valve prevents flow from the brake pipe to atmosphere. A method for operating a control valve includes supplying brake pipe air to a first side of a diaphragm through a flow path having a predetermined cross-section and permitting or preventing reference air flow to atmosphere through another flow path having another predetermined cross-section. The method further includes supplying reference air to a dump valve that prevents brake pipe air flow to atmosphere.

An electropneumatic valve unit (100, 200) for a vehicle brake system has a plurality of valve sections (102; 104; 106; 108; 204; 206) integrated into a single valve housing (101). The plurality of valve sections (102; 104; 106; 108; 204; 206) includes a front axle redundancy section (102) configured to provide a redundant supply or control pressure for controlling brakes associated with a front axle of a vehicle or a tractor, and a trailer control section (104; 204) for providing supply and/or control pressure to a trailer connected to the tractor. The redundant supply or control pressure for controlling brakes associated with the front axle of the vehicle at the front axle redundancy section (102) is derived from an output pressure of the trailer control section (104; 204).