An air braking system for a vehicle can include an air compressor, a reservoir, a first air line, a brake hub, a second air line, a control valve, a release valve, and a third fluid line. The first line can place an outlet of the compressor in fluid communication with an inlet of the reservoir. The brake hub can have a chamber in fluid communication with the outlet of the reservoir via the second line. The control valve can selectively open and close the second air line. The release valve can be in fluid communication with the chamber and having an outlet. The third line can place the outlet of the release valve in fluid communication with an inlet of the compressor.

The invention relates to a compressed-air supply system for operating a pneumatic installation in a pneumatic system of a vehicle, comprising: a compressed-air feed; a compressed-air connection point to the pneumatic installation; a venting connection point to the environment; a pneumatic main line between the compressed-air feed and the compressed-air connection point, which pneumatic main line has an air dryer; a venting valve, which is arranged on the pneumatic main line and is designed as a pilot valve and has a pilot connection point; a compressor having at least one compressor stage; and, in addition to the pneumatic main line, a pilot valve and a pneumatic pilot channel that connects the pilot valve to the pilot connection point of the venting valve. With respect to the compressed-air supply system, according to the invention, a pressure-holding pneumatic reservoir device is connected to the pilot connection point, which reservoir device is designed to provide a control pressure for the pilot connection point, in particular independently of a pressure in the pneumatic main line during venting of the pneumatic system, and the pressure-holding pneumatic reservoir device has at least one separate pilot pressure accumulator, which can be pneumatically connected to the pilot connection point via the control line.

A twin chamber air dryer for a pneumatic system of a commercial vehicle comprises: a supply inlet port, a supply outlet, a compressor control outlet, and an exhaust outlet; a first desiccant cartridge and a second desiccant cartridge, to be operated alternately; a toggling valve assembly for switching between the first and second desiccant cartridges; a pneumatically controlled purge valve switchable between a blocking basic position and an activated position; and a solenoid valve assembly. The solenoid valve assembly comprises a directional control solenoid valve for receiving an electrical direction control signal and controlling the toggling valve assembly, a regeneration solenoid valve for receiving an electrical regeneration control signal and providing pressurized air in regeneration phases of the desiccant cartridge, and a governor solenoid valve for receiving an electrical governor control signal and controlling the purge valve and a compressor mode.

A non-return valve device has at least part of a flow channel for a fluid and a movable cord-like sealing element arranged in the flow channel. The sealing element is configured such that it can be moved at least partially between a closed position and an open position, wherein, in the open position, a fluid flow is permitted through the flow channel, whereas in the closed position, the fluid flow through the flow channel is blocked by form-fitting engagement with the sealing element.

A bypass for an air dryer having an inlet, a prefiltration stage having a drain valve to purge contaminants, a pair of inlet valves in communication with the prefiltration stage to control the flow of compressed air through the desiccant towers, and an outlet coupled to the pair of desiccant towers. The bypass may be a bypass valve that is normally open to the outlet when the air dryer is unpowered and pilotable to be a closed to allow air to flow to the prefiltration stage when the air dryer is powered. The bypass may be a three-way valve that is normally coupled to the outlet and that may be piloted to connect to the prefiltration stage when the dryer is powered. The bypass may also be a check valve that opens in response to pressure in the inlet to allow compressed air to flow directly to the outlet.

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.

A pneumatic device (1) has at least one venting path (10) for venting the pneumatic device (1) in an outflow direction (R1). The venting path (10) includes a first volume (12), through which a flow can pass, a first compressed-air passage (14), and a sealing mechanism (18). The first compressed-air passage (14) pneumatically connects the first volume (12) to a pressurized part (16) of the pneumatic device (1). The sealing mechanism (18) changes between a normal state (Z1) and a sealing state (Z2). In the normal state (Z1) a flow can pass through the first compressed-air passage (14) both in the outflow direction (R1) and in an oppositely directed inflow direction (R2). In the sealing state (Z2) a flow can pass through the first compressed-air passage (14) only in the outflow direction (R1).

A purge valve with an integrated safety function, suitable for an air-drying device. In the purge valve a purge-valve body forms a first exhaust passage for connecting an inlet line to an outlet line. A purge-valve piston is arranged inside the purge-valve body to control a flow of exhaust air through the first exhaust passage upon reception of a purge signal. The purge-valve piston comprises a through opening being configured to form a second exhaust passage for connecting the inlet line to the outlet line. A valve member is arranged in the through opening and is configured to control a flow of exhaust air through the second exhaust passage. The valve member is configured to be actuated by pressurized air when a pressure value in the inlet line exceeds a threshold actuation pressure.

A compressed air supply apparatus for heavy vehicles includes a service reservoir, an air dryer in communication with the service reservoir, a purge reservoir in communication with the air dryer, a compressor for delivering compressed air through the air dryer preferentially to the purge reservoir and then to the service reservoir and a controller. The controller interrupts the charge cycle of the compressor in response to a moisture accumulation value being equal to or exceeding a wetness threshold value and the pressure in the service reservoir being within a predetermined pressure range. The controller then initiates a modified purge cycle of the air dryer, which includes iteratively regenerating the air dryer with air from the purge reservoir until at least one of the moisture accumulation value is less than the wetness threshold value and the pressure in the service reservoir is outside the predetermined pressure range.

An arrangement for a utility vehicle includes at least one air dryer unit and a regulating unit, wherein the air dryer unit and the regulating unit are designed in each case as separate units. The air dryer unit has at least one air dryer module, in particular an air dryer cartridge, at least one discharge valve and at least one control line for the pneumatic control of the discharge valve. At least one connecting line is provided in the air dryer unit with connection to the air dryer module. The connecting line leads directly to a consumer non-return valve for the air dryer unit, which is arranged outside of the air dryer unit, wherein the connecting line can be used at least partially bi-directionally and/or can be or is connected to a bi-directionally usable line section.