Patent GB-190714150-A (GB)
Title: Improvements in or relating to Electrical Signalling Apparatus.
Inventor: MOORE EDWARD ERNEST
Filed: 1907-06-19
Granted: 1908-04-09
Abstract: 14,150. Moore, E. E., and Powles, W. June 19. I n d i c a t o r s or annunciators. - A block signalling- instrument is described, by means of which three distinct indic a t i o n s may be given in any order over one line-wire by the use of momentary c u rrents. Fig. 1 shows the receiving- apparatus, which according to the Provisional Specification may also be used as a repeating-a p p a r a t u s. Fig. 3 shows another form which may be used as a repeat signal mechanism in the sending-cabin. Fig. 6 shows diagrammatically the complete apparatus at a cabin, and Fig. 7 shows another arrangement for the sending portion. A polarized armature A, Fig. 1, carries fans induced. with opposite polarities by permanent magnets A<5>, and is free to move in the field of the steel pole-pieces of the electro-magnets A, A<1> to take up one of two positions according to the polarity of the residual magnetism of the pole-pieces. Two flags A<6>, A<7>, fixed to the armature axles work behind a screen, the flag A<7> carrying two indications and the flag A<6>, only one, which, when lowered, comes in front of whichever of the indications of the flag A<7> is showing. The connexions to the magnets A, A<1> is through a relay comprising two electromagnets oppositely wound, having non-polarized armatures B<2>, B<3>, Fig. 6, at each end. The armature B<2> is so adjusted by a spring that it is only attracted by-a a strong current of predetermined strength, while the armature B<3> responds to weak currents. The repeating-instrument in the transmitting-stations consists of two oppositelywound magnets C, C<1>, Fig. 3, having an armature C<3> at one end so adjusted as to be attracted on to the pin C<3> only by a strong current. When this armature is attracted, the flag C<7> is released and falls to show its indication through the aperture in the screen. At the other end of the magnets are placed two soft-iron armatures C<5>, C<6>, induced with magnetism of opposite polarity by the permanent horseshoe magnet C<7>. When a current is sent through the electro-magnets, only one of the armatures is attracted to the magnet C<1> and repelled from the magnet C<1>. Two arms C<8>, C<9> are attached to the armatures, so that, when either armatures is attracted to the magnet C, it releases the weight D or D<1> to which are attached the flags D<2>, D<3>, and thus brings one of these flags into view. It is arranged that a positive current brings the flag D<3> and a negative-current the flag D<2>into view, but with a strong current of either kind, the flag C<4> drops in front of these. Whichever flag appears will remain in view until the transmitting commutator is turned; the rod D' is then moved, pushing the rod D<5> along ; the pins D<4>, D<7> make contact with projections E, E', or E<2> on the flags, and these are mechanically replaced, the projections E<4> at the same time engaging the projections E<5> to return the armatures C<5>, C<6>. Fig. 6 shows a complete transmitting - apparatus, the receiving - apparatus being similar, the commutator which is included being that described in Specification No. 15,677, A.D. 1903, [Abridgment Class Railway signals &c.]. The commutator has three positions. In the first, on depression of the plunger, contacts F<7>, F<8> and G<1>, G' are connected and thus a negative current from the batteries K, K<1> is sent to line, returning through earth to the contact F<6> after operating the dial F. In the second, contacts G, F<9> and F<4>, F<7> are connected and contact H, H<1> is opened and thus a positive current from the battery K alone is sent to line, the return being through earth to the dial F. In the third, contacts F<8>, F<9> and G<2>, F' are connected and contact H, H<1> is opened and a negative current from the battery K<1> alone is sent to line. The necessary indications are thus given on the dial F, and at each movement of the commutator the levers D', D<5> are operated, returning the flags ready for the next indication when the plunger isagain depressed. The currents passed to line operate a similar instrument at the receiving-stations, arriving at contact F<8> and proceeding through contact H, H<1>, electromagnet A<1>, and electro-magnets B, B<1> to earth at contact F<6>. If a weak negative current is received, the flag A<6> is shown and the armature B<3> makes contact at B<5>. If a weak positive current is received, the flag A<3> is moved away and only the armature B3 will be attracted, making contact at B<5> as before and completing a circuit through the zinc of the battery K, armature B<3>, contact B<8>, back contact of B<2>, bell signal F<3> electro-magnet A, and back to battery K, thus bringing the indication M<3> into view. When a strong positive current is received, both armatures are attracted ; a local circuit is then completed through the copper of battery K<1>, contact B<6>, armature B<2>, bell F<8>, and magnet A to the battery K<1>, thus bringing the indicator M<4> into view. The commutator may be replaced by three separate plungers N, N<1>, M<2>, Fig. 7, arranged at the ends of levers fulcrumed on pins N<3>, N<4>, N<5> with back and front contacts, extra contacts insulated from the plungers being also provided. The receiving-instrument P is as before. When the plunger N, for instance, is depressed, a strong positive current from the batteries P<1>, P<2> is sent to line through the plunger N, pin N<3>, contacts P<4>, pin N<4>, contact P<5>, and pin N<5>. Similarly the depression of plunger N' sends a weak positive current, and the depression of plunger N<2> a weak negative current to line, and when either of the plungers is depressed the receiver P is disconnected from line N<3>. For ordinary signalling the bell signals and the repeating dials may be omitted.