GB278706A - Improvements in or relating to interlocking systems for railways - Google Patents

Abstract

278,706. General Railway Signal Co., (Assignees of Henry, W. S.). Oct. 5, 1926, [Convention date]. Interlocking.-In an interlocking system which includes a traffic controlling device operated by an electric motor, a lever controlling, the circuits to the motor and an indicator showing the condition of the traffic-controlling device, and in which the motor, after completing an operating stroke of the traffic controlling device, is snubbed or braked by generating current in a closed circuit, the indicating circuit is opened by the operation of the lever and maintained open until the snubbing current energizes a relay. The traffic-controlling device may be any such device as a signal, switch-machine, a power-operated derail or point-frog. The control-lever may control two traffic controlling devices and the indication circuit may be so arranged as to be completed only when both these devices have completed their movement and the snubbing current has energized two separate relays. Fig. 1 shows an arrangement of apparatus comprising one lever L controlling the two sets of points of a cross-over road CO each operated by a switchmachine SM', SM<2> driven by an electric motor M<1>, M<2> each supplied by a separate circuit and having its own indicator circuit, including a contact 62 which is closed only when the points are in an extreme position and an indication relay IR<1>, IR<2>, and a lamp P<1>, P<2> which are alternatively put in the circuit bv the contacts 27<1>, 27<2> of the relays D<1>, D<2> which are energized by the snubbing current. In the device shown in Fig. 1, the contacts 27<1>, 27<2> are opened at each stroke of the lever L by the projections on the rod 25 which is moved downwards against the spring 26 lay the cam surface on the slide. Alternatively the circuit of the relays IR', IR<2> may be opened by an electromagnet inserted in the motor circuit so as to be energized at every operation of the motor. The resistance of this magnet is so high that with it in series, the motor does not operate; on energization of the magnet, the armature shunts the coil and the motor then operates. The switch machines are preferably of the kind described in Specification 169,795 and the line wires are provided with cross protection relays CPR', CPR<2> of known construction, for presenting operation of the apparatus by stray currents, connected in series with relays D', D<2>. The lever L is controlled by a lock-magnet LM controlled by one or a series of relays dependent upon conflicting traffic-controlling devices. Relays IR<1>, IR<2> similarly control other devices such as the signal levers for the main and diverging roads at the cross-over junction.