Abstract: A railroad grade crossing warning device designed to operate at un-guarded grade crossings without the need for expensive train detection sensors. The system utilizes the sound of an approaching locomotive horn or whistle to activate a warning at a grade crossing. The preferred device is self contained and is powered by solar panel and storage battery to provide a flashing strobe warning on the approach of a train.

Abstract: A railway switch machine including a first fluid operated actuator for switching the movable points of the rails between two extreme positions for establishing respective routes of travel for railway vehicles, valve device coupled to the first fluid operated actuator to selectively open or to close a passageway coupled to opposite sides of a pressure differential responsive movable member of the first fluid operated actuator whereby when the valve device closes passageways wherein a fluid pressure differential may be established across the movable member to operate said first fluid operated actuator to thereby switch the movable points of the rails and when the first valve device opens the passageway, fluid may be directly exchanged between either side of the 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 of the rails, a locking device and a second fluid operate