摘要 |
An improved simplified emergency brake valve device including a relay valve portion responsive to brake pipe pressure reduction at an emergency rate for actuating a logic valve portion which, in turn, when actuated, causes operation of a vent valve portion via which the brake pipe is opened to atmosphere for effecting reduction of brake pipe pressure at an emergency rate at the succeeding car in the train, thereby propogating such reduction of brake pipe pressure throughout the train for effecting an emergency brake application thereon. |