Patent GB-191210208-A (GB)
Title: Improvements relating to Automatic Block-signalling Systems for Railways.
Inventor: WHITE ALFRED ERNEST
IPC: B61L3/22
Filed: 1912-04-30
Granted: 1912-12-19
Abstract: 10,208. White, A. E., [Carson, H.]. April 30. Electrical systems, automatic and non-automatic; single-track systems; recording signals; track apparatus actuating signals on trains.-' Danger,' ' caution,' and ' clear' signals relating to the track in advance and in the rear of the train are given and recorded on the locomotive by the use of duplicate apparatus energized from train-carried sources of energy and controlled by track relays which serve to connect insulated short sections of the track rails, to insert resistance between such sections or to disconnect them according to the state of the track, these short sections serving to complete the signal circuit between insulated wheels of the locomotive. The track relay 14 of the section C controls two armatures connected to the rail 12, which is not divided into insulated sections as is the rail 11, but each rail has short lengths of insulated rail 11<c>, 11<d>, 12<c>, 12<d> connected to contacts of the relays. The armature 14<a> controls the circuits of advance sections and the armature 14<b> those of rear sections. When the relay is energized, the short sections 11<c>, 11<d>, 12<c>, 12<d> are connected to the main sections of rails 11, 12 through the front contacts of the relay, and when the relay is de-energized the contacts 11<d>, 12<d> are insulated from the rails 11, 12, and contacts 11<c>, 12<c> are connected to the rails 11, 12 through resistances 21<1>, 21. The circuit between the wheels 27, 27<1> and the insulated wheels 26, 26<1> when at the rails 11<c>, 11<d>, 12<c>, 12<d>, thus depends upon the state of the track, and relays 32, 33, 32<1>, 33<1> control the engine signals accordingly. A manually-operated switch 25 may, however, be used to control the relay 14, independently of the trains. The apparatus for front and rear signals is duplicated and may be changed over for reverse running of the locomotive by the switch 51 attached to the reversing lever 52. For forward running, the generator 30 supplies the relays 32, 33 which ara normally both energized and the 'clear' lamp 35 is lighted and the magnet 39 is energized. When resistance is inserted between contacts 11<c> and the rail 11 while the wheels 26, 27 pass, the relay 32 drops its armature but the relay 33 remains closed, and the caution' lamp 36 and magnet 38 are energized. When the contact between the wheels 26, 27 is broken at the short rails, the relays 32, 33 both open and the danger lamp 37 and magnet 40 are energized and at the same time the brakecontrolling magnet 50 is de-energized by the dropping of the armature of relay 33. The switch 51 prevents de-energization of the magnet 50 when the danger' signal is given from the rear of the train. A handoperated switch 60 for releasing the brakes is provided. The recording-apparatus comprises the magnets 38, 39, 40, 38<1>, 39', 40<1>, 61, each controlling a stylus marking two travelling bands, one 70 driven by clock-work and the other, 71, driven by the locomotive wheels through a gearing so connected to the reversing lever 52, to permit reverse running of the locomotive to move the paper forwards. The back of the paper 71 is blackened so as to transfer any marks to the paper 70.