Emergency portion for brake control valve

Abstract From the Canadian patent

An upgraded railway freight car brake control valve device comprises a novel emergency valve portion that embodies therein a minimum number of simple and inexpensive poppet valves, one of which is a double seated valve that replace, yet perform the same functions heretofore performed by more expensive slide type valves which slide valves and the flat, seats upon which they slide as they are shifted from one position to another, in their manufacture require a considerable amount of accurate machining thus increasing the cost of the valve device or which they arc an important part.