An airbrake retention system and method for controlling air flow within an airbrake system, including the steps of: receiving, with a computer system comprising one or more processors, train control data associated with stopping on a grade; determining, with a computing system comprising one or more processors, an air retention controller within a railcar brake system to control air pressure release based on the train control data; communicating, with a computing system comprising one or more processors, an air control signal, the air control signal comprising information associated with a retainer valve of the braking assembly; and controlling, with a computing system comprising one or more processors, the retainer valve to adjust from a first state to a second state based on the air control signal to control air flow between the reservoir and the air braking assembly.

A compressed-air braking system (DBA*) for a motor vehicle, includes a compressed-air supply device (1) with a compressor (2) and several brake circuits which are connected to the compressed-air supply device (1) via a multi-circuit protection valve (7) and include at least one parking brake circuit with parking brake cylinders (25.1, 25.2). In order to reduce the operating noise of the compressed-air braking system (DBA*) occurring in particular on venting of the parking brake cylinders (25.1, 25.2), it is provided that the parking brake cylinders (25.1, 25.2) can be vented, per wheel or per vehicle axle, alternately either to the surrounding atmosphere or into an additional reservoir (31) via a respective quick-venting valve (29) connected to a connecting line (28) and a changeover valve (30) arranged downstream thereof.

A compressed-air braking system (DBA*) for a motor vehicle, includes a compressed-air supply device (1) with a compressor (2) and several brake circuits which are connected to the compressed-air supply device (1) via a multi-circuit protection valve (7) and include at least one parking brake circuit with parking brake cylinders (25.1, 25.2). In order to reduce the operating noise of the compressed-air braking system (DBA*) occurring in particular on venting of the parking brake cylinders (25.1, 25.2), it is provided that the parking brake cylinders (25.1, 25.2) can be vented, per wheel or per vehicle axle, alternately either to the surrounding atmosphere or into an additional reservoir (31) via a respective quick-venting valve (29) connected to a connecting line (28) and a changeover valve (30) arranged downstream thereof.

A pre-filling device for a braking system. The pre-filling device includes a pre-filling channel, a pre-filling pressure being inside the channel when the braking system is in a rest and hydro-boost position, and a mechanical valve configured to be opened following a transition from the rest and hydro-boost position to a working position of the braking system; and a hydraulic valve cooperating with the mechanical valve setting the pre-filling pressure inside the channel. The hydraulic valve includes in a first area, facing the mechanical valve, a hole communicating with the channel, and in a second area, hydraulically isolated from the first area, a preloaded resilient element in a chamber held at atmospheric pressure. The hydraulic valve is configured to be connected or not to be connected, by a reciprocating movement inside the channel, to a hydro-booster device and to keep a predetermined pre-filling pressure upon varying of the hydro-boost pressure.

A pre-filling device for a braking system. The pre-filling device includes a pre-filling channel, a pre-filling pressure being inside the channel when the braking system is in a rest and hydro-boost position, and a mechanical valve configured to be opened following a transition from the rest and hydro-boost position to a working position of the braking system; and a hydraulic valve cooperating with the mechanical valve setting the pre-filling pressure inside the channel. The hydraulic valve includes in a first area, facing the mechanical valve, a hole communicating with the channel, and in a second area, hydraulically isolated from the first area, a preloaded resilient element in a chamber held at atmospheric pressure. The hydraulic valve is configured to be connected or not to be connected, by a reciprocating movement inside the channel, to a hydro-booster device and to keep a predetermined pre-filling pressure upon varying of the hydro-boost pressure.

An electropneumatic parking brake system for a utility vehicle includes a precontrol module configured to control at least a first control pressure. The precontrol module has a precontrol store connection configured to receive a store pressure from a compressed air device and at least one precontrol valve combination. The electropneumatic parking brake system further includes at least one manually actuatable sliding valve connected to a valve store connection and having a parking brake connection. The parking brake connection is ventilated in a first switching position of the sliding valve and a parking brake pressure at the parking brake connection is controllable in a second switching position of the sliding valve. The sliding valve has a first pneumatic control connection at which the first control pressure is configured to be controlled in order to pneumatically switch the sliding valve.

An electropneumatic valve arrangement is for actuating a parking brake function of an electropneumatic brake system of a commercial vehicle, with a pilot control unit, which modulates a pilot pressure in dependence on an electronic parking brake signal, and which is configured to be self-holding, wherein the pilot pressure can bring about a modulation of a parking brake pressure at least at one spring accumulator connection or can be modulated as such. The valve arrangement also has an emergency release connection with an emergency release path for optionally inputting an emergency release pressure, which brings about the modulation of the parking brake pressure at the at least one spring accumulator connection.

A braking system for an air brake vehicle includes a source of working pressure and a source of vacuum pressure. The system includes at least one brake actuator having a first chamber for receiving the working pressure, a second chamber for receiving the vacuum pressure; and a push rod that moves linearly in response to pressure in the first chamber and second chamber. A brake assembly is mechanically connected to the push rod for applying friction to a wheel end of a vehicle in response to the linear movement of the push rod.

A braking system for an air brake vehicle includes a source of working pressure and a source of vacuum pressure. The system includes at least one brake actuator having a first chamber for receiving the working pressure, a second chamber for receiving the vacuum pressure; and a push rod that moves linearly in response to pressure in the first chamber and second chamber. A brake assembly is mechanically connected to the push rod for applying friction to a wheel end of a vehicle in response to the linear movement of the push rod.

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.