Patent GB-190201446-A (GB)
Title: Improvements in Electrically Signalling on and Stopping Trains on Railways, and Apparatus for that Purpose.
Inventor: IMRAY OLIVER
Filed: 1902-01-18
Granted: 1903-01-17
Abstract: 1446. Imray, O., [Pfirmann, H., and Wendorf, M.]. Jan. 18. Signalling and communicating between trains; signals on engines &c. ; stopping engines &c. ; indicators and repeaters, point &c.-Relates to electric means for actuating an audible or visible signal on, and applying the brakes of, a locomotive, when it approaches in dangerous proximity to another locomotive, or to a misplaced switch &c. The bell or other signal e, and the magnet v, which controls the brake w, are connected to the battery b through the armature of the relay d. The relay coils are arranged in a main circuit including the battery a, the commutator c, the contact brush &c. q, and the conducting-rail r arranged between the ordinary rails n, the ordinary rails and engine frame &c. forming part of the return connection. When the locomotive approaches another locomotive similarly equipped, within a prescribed distance, depending on the resistance of the rail r and the adjustment of the relays d, the relay of each locomotive is actuated and closes the circuit of the battery b through the bell e and the electromagnet v, the electromagnet attracting its armature s and releasing the brake w. At branches or " dead ends " &c., contacts arranged on the points are adapted to connect the conducting. rail r with the ordinary rails, in such a manner that a locomotive or train will be stopped if it approaches misplaced points, or is in danger of running into another train &c. A contact-lever in the signal cabin enables the signalman to connect the rails r, n, to stop a train in case of an obstacle on the line. Switches 55, 56 are provided for cutting out the bell e and magnet v. To ensure an effective operative current through the main circuit in all conditions of running, the commutator c is oscillated from one of the axlesfor example, by the eccentric o on the axle l, Fig. 1. Several arrangements are described for ensuring an operative connection when the locomotive is stopped. In the arrangement shown in Fig. 10, the commutator c is geared to a governor 9, which, while in motion, holds up the crosshead 11 carrying the insulated contacts 12, 13. When the locomotive stops, the crosshead falls, and the circuit of the battery a is then established through r, 16, 12, a, 13, 18, 20, d, 17, n. In the arrangement shown in Fig. 14, the cylinder 31 is pivoted at 50 on the disc 32 fixed to the commutator, and is provided with two piston discs 40, separated by a spring 42, and mounted on the rod 33, 43, connected to the crank 39, which is driven by a belt from one of the axles. Two hooks 35, 36 are adapted respectively to engage with the notches 44, 45 in the disc 32. The spring 42 is compressed, as shown, when the rod 33 moves to the left. Near the limit of this movement, a projection on the arm 34 disengages the hook 35 from the notch 44, and the spring 42 then acts to rotate the commutator past its " dead point," to its other extreme 'position, where it is held by the hook 36. A similar operation in the reverse direction takes place on the movement of the rod 33 to the right. In a modification, the hooks are replaced by stoppins on the disc 32. In another modification, the crank 39 is driven by toothed and chain gearing, and the hooks 35, 36 are replaced by a single hook actuated by a cam on the crank spindle.