Patent GB-190926687-A (GB)
Title: An Improved Method and Means for Actuating Electro Mechanical Fog Signals for Railways.
Inventor: LOWTHIAN GEORGE
IPC: B61L3/10
Filed: 1909-11-17
Granted: 1910-06-09
Abstract: 26,687. Lowthian, G. Nov. 17. [Addition to 2973/07.] Track apparatus actuating signals on trains ; miniature signals. -Modifications in the apparatus described in the parent Specification, comprise a method of and means for actuating miniature signals in the cab, there are a pair of signals for each outdoor signal, the first of which is operated to fall to danger by the mechanical closure of a local circuit, while the second is operated to show " l i n e clear " and to replace the first by current taken up from the track, the communication between track and train being through a series of oscillating tumblers distributed over the width of the engine and operated, one half for each direction of running, by fixed track contacts, as described in the above-mentioned Specification. The train indicators consist of three pairs of signals 4, 5, Figs. 3 and 4, for home, distant, and starting signals, the danger arms 4 being attached to disks 8 mounted loose on spindles 6, and the " line clear " arms 5 to disks 7 fast on the spindle 6. The arms 4 are held up by attachment to armatures 14 of electro-magnets 13 placed in the local circuit, and fall to the horizontal position when the circuit is broken, further movement being prevented by contacting shoulders 10, 11 of the disks 7, 8. The arms 5 are operated through gearing 19, 20, from the armatures 17 of electro-magnets 16 on the line circuit, and, when the magnets are energized, the arms 5 are lifted to show through the apertures 3 and at the same time to remove the danger signal from view. They are held in this position by pawls 21 on a stop spindle 9, which pawls enter recesses 23 in disks 22 on the spindle 6. They are released by a vertically movable bar 33 provided with tappets 33<a>, which engage the counter-weights 30 of the pawls and release them, the rod being actuated from the armature 34 of an electro-magnet 35. An advance home indicator is given by a flag 24, which is operated from the armature 27 of an electro-magnet 26, which armature is connected to the spindle 9, and, when operated, places the flag 24 in view through an aperture 25, a ring 31 on the spindle 9 keeping the pawl 21 out of action during this movement. To return the danger arms 4 push studs 36, Fig. 6, are provided in the indicator casing 2, being normally held out by springs 38. The pin 39 of the stud is adapted to bear against a pin 41, which in turn bears on the short arm 14<a> of the armature 14. An audible signal is given at each actuation by a bell 44 having two hammers, one actuated on breakage of the local circuit and the other on completion of the line circuit. The engine contacts are arranged across the frame as described in the parent Specification, being attached to a cross-girder 52, Fig. 9. There are now provided five contacts on either side, and to carry them five levers 61 are mounted on spindles 56 between plates 54 attached to the girder 52, the levers being provided with terminals and lace holes 59. The levers 61 have shoulders 65 bearing against the girder flange, and consist of side plates held apart by distance-pieces 64 and carrying bolts 68 on which are loosely hung the runners 66, which have shoulders 71 for contacting with the distance-pieces 64. Springs 72, 73 are provided tp steady the motion when the runners are actuated by the line bars, which are constructed as before. The runners are operative when trailing, and, when lifted in this position, their shoulders 71 contact with the pieces 64 and lift the corresponding levers 61. Wooden blocks 76 on the levers carry contact springs 77 for contacting with screwed studs 80 bolted to the plates 54. The runners 66 consist of side plates 69 filled in with an insulating filling 90, on which a shoe 67 is supported by a bolt 91 which also acts as a terminal. Three of the runners on either side correspond to the home, distant, and starting signals, and the warning- bell circuit is led through all their contacts so that the bell is rung when either is actuated. The circuit for each danger-signal magnet 14 is led through the corresponding runners for both directions of running, and the wires from each corresponding pair run to the " line clear " magnets through a terminal board arranged at one side of the frame. The circuits for the pair of runners which actuate the " advance home " signal are normally open at the contacts 77 and are so arranged that either runner will close the circuit of the magnet 26. The fifth pair of levers are for actuating a warning bell, as described in the parent Specification, when an outdoor signal is about to be overrun, and do not require contacts 77, as the operating-current is taken from the line. The magnet 35 for returning the arms is energized from a line bar placed just beyond the starting signal, through the " advance home signal runners, the line bar being electrified when the starting signal is put to " line clear." The home signal may be repeated at the " advance home " indication by an additional line bar, but the indication will be only temporary, as the pawl 21 is held out by the pin 32. A short distance before the release line bar another bar is placed in line with the distant signal runner, which bar is electrified with the release bar to ensure that the distant signal shall have been put to safety so that its danger signal will be replaced and held in position. All the engine circuits are. led through an out-of-action switch as described in the parent Specification. In the case of level-crossings, one set of semaphores may be used to show the position of the gates.