Patent GB-190718527-A (GB)
Title: Improvements in or relating to Railway Signalling Apparatus.
Inventor: NEALE GEORGE
Filed: 1907-08-16
Granted: 1908-08-13
Abstract: 18,527. Neale, G. Aug. 16. Miniature signals; contacts, electric.-A signalrepeating indicator on the engine is operated by electric current collected from a track contact, the direction of the current being reversed by the movement of the signal levers in the cabin, in which a repeating-indicator of the same type is provided. The indicator consists of two permanent magnets F, F', Fig. 4, each having a pair of coils G, G<1> and an armature H, H<1>. The armatures, which are pivoted on a rod K, have attached plates J, J', the faces of which are coloured in two parts, the first white and green, the second white and red, of which the white parts are normally in view through spec tacles in the indicator casing, The coils are oppositely wound, so that, when a current is sent in one direction through the indicator, the attraction of one magnet for its armature is increased, and the other releases its armature, which then falls and exposes a red or green plate according to the direction of current flow. In falling, the armatures also close a local circuit to sound a bell to warn the driver that the indicator has been operated. The armatures are replaced by pulleys down the slide R, the pivoted lever S then returning the plates to their normal positions. Instead of having disks of different colours, a miniature semaphore arm may be operated to fall with the safety' signal, the 'danger' signal in this case being given by a bell alone. To distinguish between different classes of signals, an additional pair of coils T, placed one above the other, is attached to the frame, and a spindle consisting of two pieces of soft iron or steel t, t<1>, Fig. 4<a>, brazed together and provided with wing-pieces t<2>, t<3>, placed between them so that currents in opposite directions revolve the spindle one way or the other. The coils T may be brought into circuit in parallel with the coils F, F<1>, and certain known classes of signals, for instance 'home' signals, may only send sufficient current through the indicator to turn this compound spindle and cause a red or green disk attached thereto on a threecoloured plate to replace the normally visible white disk, an additional window being provided in the casing for this purpose. An additional audible signal is placed in connexion with these disks to be operated therewith. The distant signals operate both indicators. The track circuits for operating the indicator are shown in Fig. 1 ; a contact-piece D' on the end of the signal lever closes the circuit in one direction or the other, from the centre of the battery B through the cabin repeating-instrument E', which is a duplicate of the engine instrument, the insulated track contact e, the engine brush c, and the line-wire of the indicator, the return being through earth to one end or the other of the battery B. A branch circuit leads through a current indicator x, and a high resistance f to earth, this indicator showing the signalman whether he has sent current in the right direction for the signal required, before the other branch is completed by the entrance of the train into the section.