FLUID BRAKE CONTROL SYSTEM

摘要

A fluid brake control system is disclosed having an improved quick service and accelerated release control device having valves operable when rendered effective to locally reduce the brake pipe pressure to accelerate a brake application signal through a train and at other times to apply fluid to the brake pipe for accelerating the release of brakes of a train. The control device comprises a housing containing a fluid pressure differential operated abutment subject to actuation from a normal position by differences in pressure between respective brake pipe and reference fluid pressure chambers on opposite sides of the abutment. Two quick service valves of the ball poppet type are provided on one side of the abutment that are spring biased in the direction of the abutment against their valve seats to normally closed positions and have operating push rods longitudinally disposed between the associated ball poppet valves and one side of the abutment. A ball poppet valve on the other side of the abutment is also normally closed and is opened by movement of the abutment in the other direction for delivering fluid from an emergency reservoir to the brake pipe for providing accelerated release.