Patent GB-191325518-A (GB)
Title: Improvements in and relating to the Control of Trains, Railroad Vehicles and the like.
Inventor: CORTEZ-LEIGH FREDERICK AUGUSTU
IPC: B61L3/08
Filed: 1913-11-07
Granted: 1914-11-09
Abstract: 25,518. Leigh, F. A. Cortez-, and Parkinson, H. Nov. 7. Electrical systems, automatic; track apparatus for stopping trains. -The track rail is divided by insulation bonds J, J<2>, J<4>, &c., Fig. 1, into block sections with a short testing-portion X, X<1>, &c. provided by an additional insulation bond J<1>, J<3>, &c. at the beginning of each block. The track relays control the position of a track stop adapted to break a frangible tube on the train and admit air to the brake-pipe under ' danger ' conditions. The position of the track stop is indicated in the signal cabin electrically by connexion with a commutator on the track-stop spindle and to an indicator in the cabin and a polarized relay which controls a local circuit to ring a bell under ' danger ' or ' out of order ' conditions. Each short testing-section X, X<1>, &c. is provided with a track relay A, a battery G, and a thermal regulator T, and each main section Y, Y', &c. is provided with a track relay B, a battery G', and a thermal regulator T'. The tongues E, F of the relays A are mechanically connected, and the tongues E control the circuits of batteries P and magnets S<1>, which when energized retain the track stops S in the inoperative position. Normally with no train on the sections the relay A of the testing-section X is energized, and the contact E<1> is therefore tongue E, contact E<1>, resistance R, magnet S', is thus closed from the battery P through relay tongue E, contact E', resistance R, magnet S<1>, indicator magnet K and battery P. The stop S is thus inoperative. When a train enters the testing-section X travelling from left to right, the relay A is de-energized, and the tongue E falls, but the circuit of the train-stop magnet S' is still closed through the circuit from battery P through relay tongue E, contact E<2>, holding- magnet M, contact B' of track relay B (the section Y being unoccupied), stop magnet S', indicator magnet K to battery P. The energized magnet M lifts its armature, and retains a closed circuit for the magnet S' as shown when the train passes on to the main section Y. If a second train enters the testing-section X while the first train is still in the section Y or the testing-section X', it will be stopped by the stop S, because the circuit of the magnet S' is then broken at the contact B', the tongue E being also on the contact E<2>. The track relay B is de-energized in the usual way by the train wheels on the section Y, or, if the train has passed on to the next testing-section X', by the consequent short-circuiting of the relay A of that section, which drops its armature and breaks the circuit of the relay B of section Y at the contact F' of relay A of section X'. When the train stop S is in the ' safety ' or normal position with the circuits as shown in Fig. 1, a commutator N on the spindle of the track stop closes a circuit from the positive pole of the battery P to the commutator N and indicator I in the signal cabin, polarized relay O, tongue of indicator magnet K, commutator N back to the negative pole of the battery P. The current weakens the permanent magnet of the relay O, and the armature is dropped, and the local bell circuit not closed. If the stop is raised to ' danger,' the commutator N rotates, and the tongue of the indicator magnet K drops. A circuit is then closed from the positive pole of the magnet P through commutator N, tongue of indicator magnet K, polarized relay O, indicator I, commutator N back to the negative pole of the battery P. The reverse current causes the signal cabin indicator I to indicate ' up ' and also strengthens the effect of the permanent magnet of the relay O, so that it closes the local bell circuit to ring the bell. If the track stop should rise without the current in the stop magnet being interrupted, or if the current in the stop magnet is interrupted without the stop rising, the commutator N and tongue of the relay K are in such relative positions that no current flows through the indicator I, which indicates ' wrong.' At the same time, the permanent magnet of the relay O is sufficient to raise the armature, and the local bell circuit is closed. The track stop 9, Figs. 2 and 3, is secured to a casting 7, which revolves on a hollow spindle 10 fixed in brackets 11. The stop magnet 12 is fixed to the spindle, and its armature 14 is pivoted on an arm 13 fixed to the spindle 10. The armature carries a fork 15 provided with a roller 16 running in a groove 17 in the casting 7, and thereby retains the stop in the lowered position when the magnet is energized. When the magnet is de-energized, the roller 16 moves downward and out of the slot 17, and the casting 7 turns on the spindle 10 to raise the stop to the operative position. A frangible glass tube 24, Fig. 7, is carried on the train and is secured to a tube connected to the brake-pipe. A washer 31 with a small hole prevents too rapid application of the brakes, and wire-gauze 32 covers the hole in the washer to prevent broken glass from being sucked into the tube by the inrush of air. The track stop may cause the brakes to be applied, or steam shut off, or a whistle blown by any convenient means.