Patent GB-191115281-A (GB)
Title: Improvements in and relating to Railway Cab-signalling.
Inventor: MARTIN RICHARD HARINGTON
IPC: B61L3/12
Filed: 1911-06-30
Granted: 1912-06-27
Abstract: 15,281. Martin, R. H. June 30. Electrical systems, automatic; track apparatus actuating signals on and other than on trains.- A permanent magnet is provided to control the armature placed between magnetic collector arms on the engine, being positioned to hold the armature normally off ', but to carry it to the ' on ' position after it has passed a certain critical position, and to hold it closed. Two or three armatures may be utilized in a single collector to give several signals. A track magnet may also be provided to act on and be acted on by the train. The armature A', Fig. 2, may be rectangular and controlled by an adjustable horse-shoe magnet P<1> placed out of centre so that the pole P<3> normally attracts the armature. When the collector arms C<3>, C<4> are energized by a track magnet, the armature is brought into alinement, and then held in that position by the magnet P<1>, the lines of force now passing through the arms A<2>, A<3> represents the critical position. The signal given by the armature is then prolonged until the armature is reset. Instead of placing the magnet P<1> as shown, two magnets at an angle may be used. The contact closed by the armature may consist of a light spring S'‹, Fig. 4, on an arm S', and an adjustable platinum point S<9> on an arm S<6> of a lever S<1> adjustably held by a screw S<5> and spring. S<4>. Arms S<6>, S<7> are insulated and in circuit with the signal indicator through screws S<11>, S<12>. The armature may also be a hollow rectangle A<7>, Fig. 6, turning about a core A<8> held on supports A<9>, A<10>. The armature spindle may also carry a lower armature A<6>, Fig. 7, held between the poles of a magnetic controlling-apparatus consisting of permanent magnet poles P<6>, P<7> to which are clamped yokes P<9>, P<10> carrying cores P<11> ... P<14> carrying pole-pieces P<15>...P<18> When the armature A<7> is moved past the critical position, the armature A<6> is attracted and held by the poles P<16>, P<17>. The armatures may be returned mechanically or pneumatically from the cab, or by electro - magnets P<19>... P<22>. Additional central poles may be provided to give a normal position, with two ' on ' positions; or polarized poles with electro-magnetic windings may be placed to control the armature A<7>, supported to allow of two positive indications. In addition, the armature may carry a magnetizing-coil and be controlled by a non- polarized electro-magnet. A light spring on the armature spindle may complete one of two pairs of contacts, or the armature A<6> may itself close the circuits by contacting with its controlling- magnets. The armature spindle may be mounted in a vacuum tube T', Fig. 9, the contacts being made by the spring H<1> contacting with wires T3, T<4>. The tube is fitted between fixed and spring-pressed sockets T<5>, T<6>, and the wires T<3>, T<4> led to plates T<10>, T<11> on the ends of the tubes. To obtain more than two signals, three armatures A<7>, Fig. 10, are placed between collector arms C<3>, C<4> and pole-pieces C<10>, C<11>, the centre one movable in either direction, and the side ones in one direction only. Two track magnets, one in advance of the other, are used, the polarity of which can be reversed, and the armatures are so placed in circuit with the indicators as to give four distinct signals by the closing of the four contacts. The track devices may be controlled by track circuits or by treadles to give signals automatically; or these devices may be capable of being acted on by apparatus carried by the train. For this purpose, the yoke of the track magnet M<1>, Fig. 13, is reduced at M<6> and provided with horns M<7>, M<8>, between which is an armature M<9> on a fixed core M<10> and associated with a second armature as shown in Fig. 7. The last vehicle of the train carries a removable plate M<11>, which, in passing the track magnet, increases the flux therein to turn the armature to control the circuit of that or any other track magnet. The armature may be reset on the operation of an armature further ahead. The brake-van and engine carry the plates M" and have levers for raising or turning them, " tell-tale " disks being provided projecting from the sides to show when the plate is operative. The armature may alternatively be operated by a decrease in flux caused by two longitudinal plates passing over the magnet poles.