This disclosure relates to an air brake system for a vehicle having a front set of wheels having a front air brake and a rear set of wheels having a rear air brake. The air brake system comprises a front air brake cylinder included in the front air brake, and a rear air brake cylinder included in the rear air brake. A foot valve having a first side and a second side is included. A primary air tank is pneumatically connected with the second side of the foot valve, and a secondary air tank is pneumatically connected with the first side of the foot valve. A rear relay valve is pneumatically connected with second side of the foot valve and is pneumatically connected with the rear brake cylinder. A front relay valve is pneumatically connected with the first side of the foot valve and pneumatically connected with the front brake cylinder.

Park Brake Automatic Application System (PBAAS) for a vehicle includes at least one electronically controlled air valve (ECAV) and an electronic controller. The electronic controller is responsive to at least one input signal to generate a control signal which controls the ECAV when the PBAAS is activated. The ECAV is responsive to the control signal to interrupt a flow of pressurized air to the supply port of a park brake valve by closing a normally open port. Concurrent with the closing, the ECAV opens a normally closed port to provide a flow path to cause pressurized air to be exhausted from a park brake air chamber.

Park Brake Automatic Application System (PBAAS) for a vehicle includes at least one electronically controlled air valve (ECAV) and an electronic controller. The electronic controller is responsive to at least one input signal to generate a control signal which controls the ECAV when the PBAAS is activated. The ECAV is responsive to the control signal to interrupt a flow of pressurized air to the supply port of a park brake valve by closing a normally open port. Concurrent with the closing, the ECAV opens a normally closed port to provide a flow path to cause pressurized air to be exhausted from a park brake air chamber.

An air disc brake system for a heavy-duty vehicle comprising an axle. A spindle is attached to an end portion of the axle. At least a portion of an air disc brake assembly is supported by the spindle. A suspension beam has an axle support portion connectable with the axle. An end portion of the suspension beam is spaced from the axle support portion for attachment with the heavy-duty vehicle. The suspension beam may pivot about the end portion of the suspension beam. An actuator actuates the air disc brake assembly. The actuator has a movable member to actuate the air disc brake assembly. Structure is associated with the suspension beam for supporting at least a portion of the actuator. A surface defines an opening in the suspension beam through which the movable member may extend or that may receive and support a portion of the actuator.

An air disc brake system for a heavy-duty vehicle comprising an axle. A spindle is attached to an end portion of the axle. At least a portion of an air disc brake assembly is supported by the spindle. A suspension beam has an axle support portion connectable with the axle. An end portion of the suspension beam is spaced from the axle support portion for attachment with the heavy-duty vehicle. The suspension beam may pivot about the end portion of the suspension beam. An actuator actuates the air disc brake assembly. The actuator has a movable member to actuate the air disc brake assembly. Structure is associated with the suspension beam for supporting at least a portion of the actuator. A surface defines an opening in the suspension beam through which the movable member may extend or that may receive and support a portion of the actuator.

A method for adjusting brake pressures of a motor vehicle includes actuating, by a control unit, while taking into account determined dynamic state variables of wheels that are to be braked, a pressure control valve with an inlet valve for ventilating and with an outlet valve for venting the brake pressure line that is controlled by the pressure control valve. The control times of the outlet valve are determined depending on control of the inlet valve.

A brake control system includes first and second brake control units for controlling braking of first and second bogies of a rail car. The brake control units include relay valves for controlling pressurized air flow from a main reservoir to brake cylinder pipes. A bypass conduit connects an outlet of a first brake control module to an outlet of a second brake control module. A fail-safe valve moves between open and closed positions. In the closed position, the fail-safe valve prevents a flow of the pressurized air between the brake control units. The fail-safe valve provides a first pilot pressure to a first relay valve upon a failure of the first brake control unit and provides a third pilot pressure to the second relay valve in response to a failure of the second brake control unit.

A braking system for a vehicle includes an indicator device provided to reliably indicate a state of a parking brake of the system, while being simple, convenient, and economical. The system includes a body that delimits a service brake pressure chamber and/or a parking brake pressure chamber, a parking brake movable relative to the body, an unlocking part for unlocking the parking brake connected to the parking brake pressure chamber and accessible from outside the body, and a parking brake indicator device. The indicator device is configured to receive a position of the unlocking part via a state pipe and an indicator of supply and/or the venting of the service brake pressure chamber and/or of the parking brake pressure chamber. This information is processed in to detect and indicate an engaged state or a disengaged state of the parking brake.

An electropneumatic trailer control-valve unit for a vehicle includes a storage port for coupling a store of compressed air for a trailer, a brake-pressure port, and a brake-pressure pilot-control unit configured to output at least one first control pressure. The electropneumatic trailer control-valve unit further includes a brake-pressure main-valve unit configured to receive the first control pressure and to output a brake pressure at a brake-pressure port, a trailer operating-pressure port configured to receive a trailer operating pressure; and a pneumatically switched trailer protection valve with a protection-valve control port which is connected to the trailer operating-pressure port for receiving the trailer operating pressure. The trailer protection valve switches from a first switching position into a second switching position if the trailer operating pressure exceeds a predetermined first threshold value.

An electropneumatic trailer control-valve unit for a vehicle includes a storage port for coupling a store of compressed air for a trailer, a brake-pressure port, and a brake-pressure pilot-control unit configured to output at least one first control pressure. The electropneumatic trailer control-valve unit further includes a brake-pressure main-valve unit configured to receive the first control pressure and to output a brake pressure at a brake-pressure port, a trailer operating-pressure port configured to receive a trailer operating pressure; and a pneumatically switched trailer protection valve with a protection-valve control port which is connected to the trailer operating-pressure port for receiving the trailer operating pressure. The trailer protection valve switches from a first switching position into a second switching position if the trailer operating pressure exceeds a predetermined first threshold value.