A pneumatic device (1) for a brake system (100) includes a housing (3) for receiving electronic components. The housing is in fluid communication with the environment during operation of the pneumatic device (1). An exhaust path (15) having an exhaust port (17) and being in fluid communication with the housing (3) exhausts the pneumatic device (1) to the environment (5) via the exhaust port (17). An exhaust element (10) associated with the exhaust path (15) includes a liquid impermeable but gas permeable barrier between the housing (3) and the environment (5). The pneumatic device may be included in a brake system having such a pneumatic device, a commercial vehicle, and/or a method for assembly thereof.

A compressed air supply system for supplying compressed air to a pneumatic system is disclosed. The compressed air supply system comprises a compressed air input port, a compressed air output port and a vent port, a pneumatic main pipe arranged between the compressed air input port and the compressed air output port, a pneumatic vent pipe arranged between the compressed air output port and the vent port and connected to the pneumatic main pipe, a purge valve arranged in the pneumatic vent pipe for venting the compressed air supply system, a regeneration valve for controlling a regeneration flow of compressed air through an air dryer arranged in the main pipe, a governor valve for generating a pressure signal, and a first and a second pneumatic control pipe.

In a method and a device for compressed air preparation in motor vehicles, ambient air is drawn in and compressed by a compressor (2), dried in a downstream air dryer (4, 4′) and delivered to compressed air consumers (storage tanks 14, 16). The air dryer (4, 4′) is regenerated with system air stored in a regeneration reservoir (30, 30′), passed via the air dryer (4, 4′) and vented via an associated vent valve (22). In predetermined operating states, a switch is made between a delivery phase and a regeneration phase via an electrically controlled governor (36, 36′). The delivery phase of the compressor takes place at least when compressed air consumption is high, and the regeneration phase takes place in the stationary mode at the idling speed of the drive motor, to keep the delivery phases short and to have sufficient time available for regeneration.

The present invention provides a system that automatically purges contaminants from an air pressure tank when the emergency brakes of a vehicle are set. In one preferred embodiment, the system comprises a valve comprising an input port, an exhaust port, and a control port. The input port is in fluid connection with a drain on the pressurized air tank, and the control port is in fluid connection with an emergency brake line of the vehicle. When the emergency brakes are engaged, the valve is open such that the input port and the exhaust port are in fluid connection operable for air and contaminants from the pressurized air tank to be expelled from the pressurized air tank through the exhaust port. When the emergency brakes are not engaged, the valve is closed such that the input port and exhaust port are not in fluid connection.

An air dryer having a heater element associated with its valves to prevent freezing at cold temperatures. The air dryer includes a temperature sensor and an electronic controller that reads the temperature sensor during normal operations and selectively opens and closes certain of the valves when the temperature falls below a predetermined threshold to enter a safe mode that avoids freezing of the valves during operation. If an exhaust valve is open when safe mode is entered, the corresponding inlet valve is closed, both of the exhaust valves are closed, and the other inlet valve if opened. If an exhaust valve is not open, both inlet valves are opened and both exhaust valves are closed.

A drain valve for a compressed air brake system of a vehicle comprises a valve housing defining a valve chamber open at one end and a drain aperture at the opposite end. A poppet has a poppet body at least partially received in the valve chamber and provided with a seal. The poppet is slidable between a closed position in which the poppet and the seal contact the inner wall of the valve housing around the drain aperture thereby closing the drain aperture, and an open position moved away from the drain aperture. A spring urges the poppet to the closed position. The poppet and the seal are incorporated in a single multi-component injection molded plastic part comprising at least two components. The poppet body is formed of a first plastic component and the seal is formed of a second plastic component partially embedded in the first plastic component.

Compressed air supplied into a housing is expanded for reducing air humidity in the housing in response to the expansion of the compressed air. As a result, it is possible in a simple manner for a component to be operated in a dry environment. The component can be dried and condensation on the component can be prevented.

An oil separator includes a heating device that heats liquid stored in a liquid storage portion, a connecting pipe that connects the liquid storage portion to an external device that utilizes oil, an opening/closing device that selectively opens and closes the flow path of the connecting pipe, and a determination device that determines whether the liquid stored in the liquid storage portion should be delivered to the external device. The opening/closing device is configured to open the flow path of the connecting pipe when the determination device determines that the liquid accumulated in the liquid storage portion should be delivered to the external device.

The operation of an air compressor is controlled to control engine performance to thereby improve the performance of the vehicle. A compressor (4) driven by an engine (3) of a vehicle and supplying compressed air to loads (51-54) is controlled by an ECU (2). A loaded state and an unloaded state of the compressor (4) are switched between each other according to the requirements from the loads (51-54). When the vehicle requires braking force, the compressor (4) is set to the loaded state irrespective of the requirements from the loads (51-54).

A compressed-air treatment system and operating method are disclosed. The compressed-air treatment system has a first valve unit configured to charge a control line for a compressor with pressure and a pressure regulator valve unit configured to release pressure from a feed line, A control port of the pressure regulator valve unit is connectable to a second valve unit. A regeneration line which has a check valve for regeneration and which is utilized for a regeneration of a dryer cartridge is connected directly to the control line. During a filling operation the compressed-air treatment system is configured to release leakage air of the regeneration check valve via the first valve unit to surroundings. The filling operation is an operating state in which the compressor is activated to perform a supply of compressed air to a vehicle compressed-air system.