Fluidically operated railway switch machine

A railway switch machine comprising, fluidically actuating means for switching movable points of rails between two extreme positions, valve means coupled to said fluidically operated actuating means for selectively controlling fluid flow in a pair of passageways each of which is coupled to opposite sides of a pressure differential responsive movable member of said fluidically operated actuating means whereby when said valve means connects a source of fluid pressure to said passageways between said opposite sides of said fluidically operated actuating means so that a fluid pressure differential is established across said pressure differential responsive movable member to operate said fluidically operated actuating means to thereby switch the movable points of the rails from one extreme position to the other extreme position and when said valve means interconnects said passageways between said opposite sides of said fluidically operated actuating means fluid is directly exchanged between either side of said movable member such as to permit the movable points of the rails to be moved from one extreme position to the other extreme position by the passage of a railway vehicle trailing the movable points, said valve means includes an integrally formed bypass and directional valve means having a movable valve member which is adapted to assume a first position of the movable valve member to establish a fluid passage between opposite sides of said pressure differential responsive movable member whereby to permit said exchange of fluid between opposite sides of said pressure differential responsive movable member and which is adapted to assume another position of the movable valve member to prevent direct fluid connection between opposite sides of said pressure differential responsive movable member, and resiliently-loaded latching means cooperatively associated with said fluidically operated actuating means for latching the movable points of the rails in either of the two extreme positions so that the springiness of the movable points or vibration caused by passing railway vehicle is incapable of causing the movable points of the rails to assume an intermediate position between the two extreme positions.