A braking system for railroad freight trains and a novel relay valve for use in the system are disclosed. The relay valve permits the brake system to be configured so that the requirement for expensive control valves is minimized. The novel relay valve is interposed between the control valve and a number of brake cylinders. Upon a signal from the control valve, the relay valve delivers brake air to the cylinders from a pre-charged reservoir or other source. The novel relay valve includes primary and secondary flow valves to cause air to be delivered to the brakes in a controlled manner. An exhaust valve arrangement in the relay valve permits the brakes to be released.
An electronic pneumatic brake system for trains which significantly improves brake cylinder pressure build-up time and facilitates essentially instantaneous and simultaneous braking on all cars of the train. The electronic pneumatic brake system includes electronic pneumatic control valves on the cars which individually control the braking on each car or a pack of cars and which are regulated by an electronic pneumatic controller on each car that receives electronic braking and release signals by way of wireless communication from an electronic head end unit on the lead locomotive, or where no head end unit is provided in the locomotive, receives pneumatic braking signals through the brake pipe.
An electronic pneumatic brake system for trains which significantly improves brake cylinder pressure build-up time and facilitates essentially instantaneous and simultaneous braking on all cars of the train. The electronic pneumatic brake system includes electronic pneumatic control valves on the cars which individually control the braking on each car or a pack of cars and which are regulated by an electronic pneumatic controller on each car that receives electronic braking and release signals by way of wireless communication from an electronic head end unit on the lead locomotive, or where no head end unit is provided in the locomotive, receives pneumatic braking signals through the brake pipe.
