Patent GB-190208066-A (GB)
Title: Improvements in or relating to Block-signal Systems for Railways.
Inventor: BOULT ALFRED JULIUS
Filed: 1902-04-07
Granted: 1902-08-07
Abstract: 8066. Boult, A. J., [Miller, A. C., Miller, H. V., Price, J. D., Failing, G., and Council, W. H.]. April 7. Signalling and communicating between trains; signals on engines &c. ; signals, lamp ; contacts, electric.- Relates to block signalling systems in which both train-carried signals and signals on the line at the block junctions are employed. Fig. 1 shows diagrammatically the arrangement and connections of the track apparatus, and Fig. 5 the apparatus on the train. A relatively - short insulated rail section b<2>, b<3> is employed for each track rail b<4>, b<5> at the block junction. The' danger' and ' clear' lamp signals E', E<2>, Fig. 5, are connected in circuit a', a<2>, through the wheels &c. E', with a local battery E and the contacts a<4>, a<6> of the polarized armature E<3>, one or other of the lamps being illuminated according to the position of the armature. The armature carries a coil E' of relatively-low resistauce connected to the leads a<8>, a<10> of the relatively high resistance magnets E<5>, E<6>, which are energized both by the battery Q and by the track battery S, the connections of the latter being through the leads a<2>, a<14> from, say, insulated engine and tender connections E<7>, E<8>, when the latter bridge the rails b<4>, b<2>, &c. The circuit of the battery S is controlled by a polechanger I, Fig. 1, the position of the armature E<3>, and consequently the signal given on the train, depending on the direction of the current received from the battery S. The clear,' ' caution,' and 'danger' signals 55, 56, 57, Fig. 1, on the line are adapted to be illuminated by storage batteries C, which may be fed from primary batteries P, the lamp circuit being completed only on the approach of a train, by the dropping of the armature D<6> of the magnet D<5>, which is energized by the battery D of the preceding section. The battery and lamp circuits are controlled by electromagnets N, and polechanging electromagnets M, energized, respectively, by the track batteries A and train signal batteries S. The main track batteries T, connected to the advance ends of the rail sections b<4>, b<5>, energize the pole-changing magnets H<5>, R<6>. The magnets H<5> actuate the ordinary contact-making armature H<4>, but the magnet H<6> is reversely wound, and serves to produce consequent poles, which, in conjunction with the coil I' on the polarized armature I, produce a differential action on the armature, to close it or hold it open as required. The current through the coil I<4> from the battery L is always in the same direction, while that through the main track magnets H<5>, H<6> reverses. The whole current from the main track battery is employed to close the armature H<4>, and then a portion of the current is shunted through the reversely-wound coil H<6>. The armature I constitutes a pole-changer and circuit-changer for the signal batteries. When a train approaches a section fully cleared in advance, it receives two 'clear' signals by the lamps E<2>, 55, the lamp 55 being cut out and the danger' lamp 57 switched in when the train enters a section. If, then, a second train approaches the second block section in the rear, it receives a ' danger' signal by the lamp E<1> and a 'caution' signal by the lamp 56, the latter signal being replaced by the ' danger' signal 57 when the train enters the section. The block sections may be lengthened by the interposing relay sections F<1>, Fig. 5, provided with track equipments comprising the track magnets and armatures H<5>, H<6>, H<4>, I, &c., and a switchman's lamp signal illuminated by the battery D of the section iu the rear. Fig. 10 shows a copper rail bond for electrically connecting two adjacent rail sections. The ends of the bond 115 are made concave and somewhat flattened, and are passed through holes in the webs of the adjacent rails 117. They are then bent back on themselves to form wedges 116, which are driven tightly into position, the free ends 118 being finally bent back against the webs, as shown. Fig. 11 shows a stand for the line signals. The casing on the hollow standard 118 is divided into six chambers containing the lamps W, G, R, similar pairs of lamps being connected in parallel to their leads 125, 127, 129, so that, in case of one lamp failing, the whole signal will not fail. The casing may be provided with a lens 123, or each chamber may have a separate lens.