Patent GB-190913254-A (GB)
Title: Improved Apparatus for Signalling upon Railways.
Inventor: MILLER DONALD JOHN GUNN
IPC: B61L3/10
Filed: 1909-06-07
Granted: 1910-01-20
Abstract: 13,254. Miller, D. J. G., and Spence, W. H. June 7. Track apparatus actuating signals on and other than on trains; miniature signals.-Signals are given on engines by means of insulated track ramps, placed at different heights for different signals, which are adapted to be energized from the cabin to complete circuits through the engine apparatus to prevent a danger signal, which is otherwise given mechanically, from being given either visually or audibly to the driver, and to give a visual safety signal in the cab. Indicators in the cabins also notify the passage of a train over the ramps. The track apparatus consists of ramps 12, 13, 14 for 'distant,' 'home' and 'starting' signals respectively, each having a connexion to switches 17 in the cabin, the connexion passing through an electro-magnet 22 which, when current flows, attracts its armature 24 to exhibit the signal 25 through the aperture 26. The first switch 17 is connected through a bell 23, a battery 19, and a main switch 18, to the running-rails. The switches must be actuated successively to energize the ramps. Alternatively, the magnets 22 and the bell 23 may be omitted and the switches 17 may be the ordinary operating-levers, and may each be connected into circuit to avoid the necessity for successive actuation. Further, the system may be used in connexion with automatic track signals, which are operated by solenoids and reset from track contacts by placing a pair of mercury cups on the signal post in circuit with each signal ramp and providing the semaphore with a fork which dips into the cups and completes the circuit when the semaphore is placed at "line clear." The engine apparatus, Fig. 5, consists of a shoe 1 mounted on a rod 2, which carries indication boards at the top, as shown, to indicate the signal being passed, and a tappet 4 which governs the movement of the semaphore 3, which it normally holds vertical. When the shoe rises on a ramp, the counterweighted semaphore is allowed to rise, but, if the solenoid 6 is energized by current from the ramp, is held in the ' safety' position by the tappet 5 on the rod of the solenoid plunger. If the solenoid is not energized, the signal rises to 'danger' ; a bell 7 is rung by a hammer 8 at each actuation of the signal. The semaphore may be held out of operative position by pulling down a lever pivoted to its spindle which lever is normally in the signal circuit. Interlocking points and signals.-At points, two ramps may be provided, each connected to a terminal of a switch operated from the points operating rod so that the ramps are alternatively energized according to the position of the points. The "branch" ramp on the train may have included in its circuit an electro-magnet operating a signal similar to the cabin signal shown in Fig. 3. Audible signals.-An audible danger' signal may be given on the engine when the shoe is raised by a projection 49, Fig. 7, moving the spring-held lever 50 out of the position in which it locks the counterweighted rod 46 attached,to the spindle of a steam whistle 48. The rod is then raised and the whistle sounded if the solenoid 53 is not energized from the ramp. If the solenoid is energized, the catch 54 is held up against the spring 55, and the rod 46 is held. If an engine is stopped on a ramp, the driver may stop the whistle by setting the lever 46 behind the catch X, and the lever is returned to normal when the solenoid is energized and a 'safety' signal given.