Patent GB-191414189-A (GB)
Title: Improvements in or relating to Railway Safe-running Devices.
Inventor: ANGUS ARTHUR REGINALD
IPC: B61L3/10
Filed: 1913-04-17
Granted: 1914-07-17
Abstract: 14,189. Angus, A. R. Feb. 13, 1913, [Convention date]. Electrical systems, automatic; track apparatus actuating signals on trains and other than on trains, and for stopping trains.-In systems in which trains moving in different directions along a track have different poles of generators on the trains in contact with track ramps to which are connected polarized relays controlling circuits which include other track ramps for actuating signals or train-controlling apparatus on other trains, current passes from one of the track contacts through a switching- instrument which secures a connexion, either through a resistance only, or through contacts which test the position of another track instrument.. The train is warned or stopped if any track switching-instrument fails to complete its required movements, in which case either no current or a current too small or too large passes in the train circuit and puts in action the signals or stopping-devices thereon. Resistances are inserted in the circuits of the ramps and of the polarized relays and of the contacts controlled by the armatures thereof, and are so arranged that the resistance of the track circuit when the train is in contact with any ramp, if the track is clear, is such that a current of normal value passes through the circuit and gives a clear signal, and in order to ensure that the apparatus on the train is correctly set for movement in a particular direction over the track, the resistance included in the track circuits from the ramps for one direction of running is less than that for the other direction, and the resistance of the train circuit is adjusted so as to keep the total resistance approximately constant. Means such as are described in Specification 9090/13 are provided at turntables and reversing loops to ensure correct setting of the engine switches. Fig. 1 shows the apparatus carried by a train, and Fig. 2 shows the track circuits for a single track system of signalling on trains. The apparatus carried on the train includes a relay magnet 34 in series with a source of energy 32 and two reversing-switches 100, 41, the former of which is operated by hand, and the latter by the reversing-gear of the engine. The relay 34 controls the circuits of magnets controlling the clear-signal whistle 63, the dangersignal whistle 26, and the valve 22 actuating brake-valve and throttle-valve operating-devices and the miniature signal 28. These latter circuits are normally closed through contacts 9, 11, 12 on the shoe 10, but are broken at these contacts when the shoe contacts with the ramps, and substitutional circuits are completed by the relay 34 if current of a normal value passes through its coils. The switches 41, 100 are provided with resistances 64, 65 which are so connected that, for, say, a down journey, the positive pole of the generator 32 is connected to the shoe 10 without either resistance 64, 65 in circuit, and for an up journey, the negative pole is connected to the shoe with one of the resistances in series. On a down journey, with the arrangement of track circuits shown in Fig. 2, in which the parts are shown in the position occupied when the section is clear, the train shoe first makes contact with the warning contact 1, and a circuit is completed from the generator 32 over ramp 1, contact 83, wire 93, and resistance 91, which is in parallel with the resistance 89 and coil 95 of the switching-instrument Y, to earth. The armature 74 is moved by the coil 95 to the open position, and the above circuit from the wire 93 passes over the resistance 89 and afterwards divides through the coil 95 and resistance 90. Under these circumstances, the normal current passed in the train circuit, and the line-clear signal is actuated. If the armature 74 fails to move, a large current passes, and if the armature 73 is in the open position owing to the occupation of the section bv a train, then the above circuit is open at the contact 83 and no current passes in the train circuit, and in both cases the danger signals are actuated. On reaching the contact 2, the engine circuit is completed through the coils of the polarized relay 251 and resistance 257. The armature 253 is moved to contact 255 and completes the circuit over the contacts 83, wire 93, resistance 89, resistance 90, and coil 95 arranged as above, the current being of a normal value. This tests the position of armatures 73, 74 and gives a clear signal if they are in proper positions. At the contact 3, the train circuit is completed over the resistance 85 and the coil 97, which are shunted by the resistance 86, to earth. The coil 97 moves the armature 73 to ' open ' position, and the coil 97 is put in parallel with the resistance 87, both being in series with the resistance 85. Under these circumstances, the current in the engine circuit is normal, and the line-clear signal is given if the armature 73 has moved. The section is thus blocked to other trains entering the section from either end, since the contacts 83, 84 are both open, and a warning signal will be given at contacts 1, 6, and a stop signal at contacts 2, 5. The first train then passes through the section and, at the contact 4, completes its circuit through the coil 96 and resistance 92 in parallel to earth. The coil 96 moves the armature 74 to ' closed ' position, and the circuit to the resistance 92 is broken. The current is of normal value if the armature has moved, thus testing the operation thereof. At the contact 5, the circuit of the relay 261 is closed through the resistance 267, but the current is in such a direction that the armature is not moved, and the resistances are such as to give normal current in the circuit. At the contact 6, the circuit passes over the contact 84 and wire 104 to the coil 98 in parallel to the resistance 88, and the armature 73 is moved to closed position and cuts out the resistance 88. The resistance of the coil 98 alone is such that normal current passes in the circuit, thus giving a line-clear signal if the parts of the apparatus have moved to the lineclosed position, leaving the section ready for the passage of another train in either direction. The operation of the system for an up train is somewhat similar to that for a down train, but the opposite pole of the generator being connected to the shoe 10 through a resistance 64 or 65, the current passing through the magnets is reversed in direction and, if the track resistances are the same, is diminished in magnitude. For instance, an up train reaching contact 6 completes a circuit over contact 84 and wire 104 to the coil 98 and earth, but contrary to action of a down train, the armature 73 is now moved to 'open' and puts the resistance 88 in parallel to the coil 98, and this arrangement in series with the resistance on the train is such as to give a normal current in the train circuit. At the contact 5, the relay 261 receives current in such a direction as to close its contacts 265 and test the above circuit. At contact 4, the relay 96 is caused to move its armature 74 to ' open ' and to put the resistance 92 in parallel to the coil 96, the resistance 64 or 65 in series therewith giving a normal current. Thus resistances in the track circuit, which are adjusted to give a normal current on a journey in one direction and actuate clear signals on a train, are such as to give a danger signal if a train proceeds over the line in reverse direction without changing over its train-circuit connexions. In a modified arrangement, resistances are connected in series with the coils of the switching-instruments and are shunted bv the armatures. A system is also described in which the sections are arranged to overlap and the circuits between instruments at the ends of a section are carried over contacts on the intervening instrument. Fig. 5 shows a system in which only one line-wire is necessary, quick-acting relays 214, 215 being inserted in the circuit so as to cut out the switching- instruments at the rear end when a train is over the first or last contact in a section. Resistances may be arranged as desired to keep the current within the predetermined limits, if all is in order, but are not shown on the drawing. While a train moving on an up journey is over contact 1, current passes through magnet 214, line-wire 220, armature 222, and coil 96. The armature of magnet 214 cuts out the coil 97 from the circuit, and coil 96 puts the armature 74 to 'open' position. At contact 2, a similar circuit is made, but includes also coils 251 and contact 255. At contact 3, the coil 98 is energized and puts the armature 73 to ' open ' position. At contact 4, coil 95 puts the armature 74 to ' closed ' position. At contact 5, an ineffective circuit is made through coils 261 and resistance 267. At contact 6, the circuit includes the relay 215 (which cuts out the coil 96), armature 218 of relay 214, and coil 97, which resets the armature 73 to closed position.