. Locomotive engineering : a practical journal of railway motive power and rolling stock . the exhaust openinginto the atmosphere by which the com-pressed air is allowed to escape. .5 is acircuit breaker, worked by a pin on theside of the piston rod, being so arrangedas to break the circuit operating thecautionary signal whenever the home sig-nal assumes the danger position. The operation of the signal may be ex-plained as follows ; Supposing the signalto be in the danger position, and that thesignal circuit, or the one energizing themagnet, had just been closed by the track-circuit relay. The
. Locomotive engineering : a practical journal of railway motive power and rolling stock . the exhaust openinginto the atmosphere by which the com-pressed air is allowed to escape. .5 is acircuit breaker, worked by a pin on theside of the piston rod, being so arrangedas to break the circuit operating thecautionary signal whenever the home sig-nal assumes the danger position. The operation of the signal may be ex-plained as follows ; Supposing the signalto be in the danger position, and that thesignal circuit, or the one energizing themagnet, had just been closed by the track-circuit relay. The current would thenflow through the magnet I\l, causing thearmature A to be attracted. This pressesthe valve )from its seat, at the same timeseating the valve ], closing the exhaustand allowing air from the supply pipe5 to flow along the passages E and Fvatothe cylinder behind the piston P, forcingit through the cylinder the length of itsstroke and clearing the signal. As thepiston was pressed down, the spring of thecircuit breaker would be released, the cir-. FiG. 9. cuit closed, and, if the next succedingblock was clear, the cautionary signalwould also assume the All Clear or Safety position. A diagram representing a piece of track,divided into several block sections, with thenecessary signals and the several electriccircuits, is shown in Fig. 7. The uppersignal, with the pointed end, on each pole,is the home signal ; the lower one, withthe end notched, is the cautionary signal,showing the condition of the next succeed-ing block ahead. An engine is supposedto be in Block 2, the signals of the severalblocks being shown in the position theywould assume in consequence of this blockbeing occupied. In Block i we find that,as there is no train or part of a train inthis block, the current from the battery isflowing through the rails of the block andenergizing the relay, the armature being held up and the signal circuit energizes the magnet of the home-signal cylinder, an
Size: 1480px × 1689px
Photo credit: © Reading Room 2020 / Alamy / Afripics
License: Licensed
Model Released: No
Keywords: ., bookcentury1800, bookdecade1890, booksubjectrailroa, bookyear1892
