Patent GB-191104882-A (GB)
Title: Improvements in Signalling and Speed Controlling Apparatus for Railway Trains.
Inventor: DAMMOND WILLIAM HUNTER
IPC: B61L3/10
Filed: 1911-02-27
Granted: 1912-02-22
Abstract: 4882. Dammond, W. H. Feb. 27. Electrical systems, automatic; track apparatus actuating signals on trains and for stopping trains; miniature signals.-Signals or speedcontrolling apparatus on a train are maintained normally in ' clear ' position by a closed local circuit passing through a circuit - breaker operated by a rotating and rising contacting member for engaging fixed track ramps and through the contacting member and through contacts on the gravity-actuated signal-controlling means; at a ramp, the local circuit is broken, and, if a clear signal is to be transmitted, current is supplied from the ramp through the contacting member, but not through the circuit-breaker and contacts on the signalcontrolling means, to the signal magnet. Fig. 2 shows arrangement of ramps for giving various signals on the train such as ' distant ' at the ramp D', first home at the ramp h<1>, second home at ramps H<1>, d<1> and h<2>, d<2>; manuallycontrolled circuits as at the first home ramp may be used throughout, or automatic control as shown may be adopted. Fig. 1 shows the engine apparatus in normal position. The magnet E holds the whistle valve closed and is in parallel with the magnet M<1> controlling the signal g. The valve may be put out of action by a switch S, which in this position cuts out the magnet M<1>, thus preventing replacement of the signal g but causing a bell a to sound, indicating that the clear signal may be received by resetting the switch S. For this purpose, part of the conductor 12 is replaced by the conductor 19. The contacting member W<1> comprises metallic insulated segments w<8> shown in heavy lines connected to the divided periphery w<7> and running past a fixed block w<10>: Normally the connexions are spaced to maintain connexion between the brushes b', b<3>, but if the wheel W<1> is broken, the circuit is no longer completed, and a danger signal is given. The circuit keeping the home signal y at ' clear ' is from battery G by wire 3, contacts of armature A<2> of the signal magnet M<2>, wire 4, circuit-breaker B<2>, through the insulated contacting member W<2>, magnet M<2>, and wires 7, 2. The circuit to the magnet M<1> is from battery G, by wire 3, contacts of armature A<2>, wire 8, contact of armature A', wire 9, circuit-breaker B\ contacting member W', wire 12, to magnet M' and wires 13, 2. These circuits are normally closed, but when a ramp is reached the circuitbreakers are opened and the magnets M', M<2> drop their armatures unless current is received from the ramp through the contacting-member W<2> by wire 6 to magnet M<2> and earthing-wheel W<5>, or through a similar circuit to magnet M'. If no current is received from the ramps, the signals move to ' danger ' and remain so until the ramp circuit is completed, the engine circuit for the distant signal being broken at both the armatures A', A<2>, and that for the home signal at armature A<2> only. The whistle is sounded when magnets E, M' are de-energized, but may be stopped by placing the switch S to support the armature of the former, in which position a bell a is put in circuit to be sounded when the clear signal is to be given. The switch S is then replaced to normal position, and the semaphores are reset by the current from the ramps. For the purpose of allowing a train to move forward beyond a danger signal point, the additional semaphore c connected to home semaphore y and the covering-plate F controlled by magnets M<3>, M<4> are used. Either magnet M<3>, M<4> is able to hold the armature A<3>. Additional circuit-breakers B<4> control the circuit from battery G through armature A<2>, wire 4, cucuit-breakers B<2>, B<4> to magnet M<4>. Thus the magnet M<4> is not energized from battery G when the home semaphore y is at danger. The circuit of the magnet M<3> is from battery G, by conductor 22, additional circuit-breaker B<3>, wire 24, armature A<3>, to magnet M<3>. If the train with signals at clear reaches the distant-signal ramp, the signal g goes to danger but the plate F is held up by magnet M<4>. At the home-signal ramp, the home signal y and the additional signal c go to danger, and the shutter F falls when the wheel W<1> is lifted, but is reset when it falls again. At ramps d', H<1>, the signals y, c may be set to clear by current from a battery through a hand-operated switch J, to indicate that the train may proceed to the ramps d<2>, h<2>.