US576493A - big-gar - Google Patents

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US576493A
US576493A US576493DA US576493A US 576493 A US576493 A US 576493A US 576493D A US576493D A US 576493DA US 576493 A US576493 A US 576493A
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circuit
magnet
section
gate
crossing
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61LGUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L5/00Local operating mechanisms for points or track-mounted scotch-blocks; Visible or audible signals; Local operating mechanisms for visible or audible signals
    • B61L5/04Fluid-pressure devices for operating points or scotch-blocks
    • B61L5/045Fluid-pressure devices for operating points or scotch-blocks using electrically controlled fluid-pressure operated driving means

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Train Traffic Observation, Control, And Security (AREA)

Description

(No Model.) a Sheets-Shed; ,1.
- J. S.-BIGGAR.-
ELECTRICAL CIRCUIT FOR OPERATING AUTOMATIC RAILWAY GATES- Patented-Feb. 2, 1 897.
(No Modem" v 3 Sheets-Shee 1: 2. r J. S. BIGGAR. ELECTRICAL CIRCUIT FOR OPERATING AUTOMATICRAILWAY GATES. I
Patented Feb. 2', 1897.
l-x s 3 Sheets-Shea 3.
(No Model.)
v J. s. BIGGAR; ELBGTBIUAL CIRCUIT FOR OPERATING AUTOMATIC RAILWAY GATES. No. 576,493. Patented Feb. 2, 1897.
GW A UNrrEn STATES ATENT OFFICE.
JOHN STUART BIGGAR, OF CHICAGO, ILLINOIS, ASSIGNOR TO MARY E. II. BUTTER, OF SAME PLACE.
ELECTRICAL CIRCUIT FOR OPERATING AUTOMATIC RAILWAY-GATES.
SPECIFICATION forming part of Letters Eatent No. 576,493, dated February 2, 1897'. Application filed a ry 22, 1895. Serial No. 535,764. (No model.)
To all, 1071,0122, it nmy concern: mechanism in the gates. An exhaust-pipe Be it known that I, JOHN STUART BIGGAR, A connects with the feed-pipe, and both the residing at Chicago, Cook county, Illinois, exhaust and feed pipes are provided with suithave invented an Electrical Circuit for Operable valves or cocks at a, respectively, which 5 ating Automatic Railway-Gates, of which the are so connected by a rod a that when one following is a specification. valve is open the other is necessarily closed. My invention has special reference and ap- This rod aetuates the valves through hellplication to that class of railway-gates either cranks a a whose free arms are connected of the gravity, electric, or pneumatic type to rods a a, which are operated as follows: 10 designed to be automatic in action by the Upon asuitable support I mount a guidemovements of trains upon the track, and I frame B, in which travelsaweightB, attached will describe it in connection with automatic to a piston-rod b. At one side of the guidegates, therefore, for convenience. frame I provide a catch or dog B adapted to In general terms the means consist of a project below the weight when raised. At a 15 novel disposition of electrical devices and. somewhat higher plane I arrange a similar circuits forautomatically controlling the lowdog B adapted to project above the weight ering of the gates and also for ringing an when in its lowered position. Arranged veralarm. I provide for the lowering of the gates tically below the weight is a barrel B prowhen the train approaches to within apredevided at one side with a rack of teeth Z). 2o termined distance and for the raising of the This barrel contains a compressible spring gates only after the last car has entirely B abutting at its ends, respectively, against cleared the crossing or other point, regardless the bottom of the barrel and against the pisof the length of the train, as the mechanism ton-head or disk (3 adapted to travel in the is controlled by the last truck of the last car. barrel against the tension of the spring. This 7 5 25 I also embody other novel and advantageous disk is provided with a rod adapted to bear features which will be apparent from the against the weight thereabove. description of the invention as hereinafter Mounted upon the frame are four vertical set forth; and my invention consists in the rods 0 C C C arranged in pairs on either features and details of construction hereinside of the mechanism just described. The 0 after described and claimed. rod C has a sliding weight 0, while in its path In the drawings, Figure 1 is an elevation, is arranged a trip mechanism consisting of a partly in section, of one form of gate-operatlever 0*, held in a normally horizontal posiing mechanism which is under the control tion bya spring. Opposite the ratchet-teeth of my electrical devices and operatesv in conon the barrel is a block 0 provided with 3 5 nection therewith; Fig. 2, a diagrammatic corresponding teeth. This block is kept in view of the electromagnets and circuits; Fig. normal engagement with the barrel by means 3, a detail of one of the magnets and its arof a spring, but may be released by the downmature, and Fig. 4 a diagrammatic view of a ward movement of the lever which Withdraws modified arrangement of circuit and electrothe block by the contact of the upwardly-pro- 9o 40. magnets. jeeting arm 0, bearing against a stud upon For the purpose of explaining my invention the block. An operating-rod C connects the I have selected the operating mechanism dog B to the lever and is adapted to release shown in Fig. 1, which is of the type known the former from engagement when the latter as pneumatic, but on this construction I is depressed. The rod C is provided with a 5 45 make no claim. This mechanism is under similar weight 0 adapted to strike in its decontrol of electrical devices which constitute scent a lever C", and an operating-rod C my invention, as hereinafter set forth. similar to rod 0, is adapted to actuate the Iprefer to use a tank A, communicating dog mechanism B witha suitablesource of compressed air and A device for lifting the tripping-weights is too 5o provided with a feed-pipe A, which connects provided consisting of a rocking beam D, pivwith the ordinary fluid-pressure-actuated oted in the upper portion of the guide-frame.
The ends of the beam carry similar rods I) D, having pivoted at their ends sleeves (Z (1, adapted to slide on the guide-rods O and 0 respectively. Each sleeve carries a laterallyprojecting arm 01 or 01 projecting in the path of its respective tripping-weight.
Secured to the beam at one side of its pivotal point is an arm D having its other end secured in an adjustable manner to the vertical rod b. In order to lock the beam in the position shown in Fig. 1, I provide an arm d having a shoulder adapted to engage the arm 01*. A rock-shaft D connected to suitable tread-levers on a railway-track, (not shown,) is mounted in the frame and carries an arm I) in contact with the bottom of the barrel.
Electromagnets E E are located adjacent to the weights 0 c in such position that their pivoted arm atures e c will project in the path of the weights and serve to support them when said weights are elevated by the beam mechanism.
Before proceeding to set forth the electrical circuit, appliances, &c., of which the magnets E E form a part, I will explain the operation of the mechanism above described. Assuming that a train is approaching a crossing, it will close a circuit and thereby energize magnet E, attracting its armature and allowing the weight 0 to drop. The lever C' will thereby be depressed,withdrawing the block C from engagement and simultaneously thrusting the rod a downward, opening the valve a and closing valve a, whereby air-pressure is supplied to the gate-cylinder and the exhaust closed. The gates are now lowered.
Simultaneous with the withdrawal of the block the dogmechanism B is operated by the lever and the weight B allowed to drop, being held in its lower position by the dog B The spring is thereby compressed somewhat in the barrel, and by the lowering of the rod 1) thebeam D is operated and the weight a is raised back to its normal position, while the lifting device on the other side is lowered to allow free descent of the weight 0 when it is time for it to act. When the train passes over the track-lever near the crossing, the shaft D will be rocked and the barrel forced upward against the tension of the inclosed spring. The lever C is kept in its lowered position by the dog B which is forced to the right, Fig. 1.
\Vhen the train has cleared the crossing, it will close another circuit and cause the magnet E to attract its armature, and thereby allow the weight to drop. The lever c is thereby depressed and the valve a closed and the exhaust ct opened, whereby the gate-cylinder will exhaust back through the pipe A At the same time the dog B is withdrawn and the tension of the barrel-spring will force the weight B upward and also rock the beam and carry the tripping-weight c and support it in the position shown.
Considering Fig. 2 of the drawings, I have i shown for the purposes of a full understanding of the invention a double-track railway, although my invention is applicable to a simple single-track line. That portion of track in the neighborhood of the crossing and gates is divided up into insulated sections in the following manner: At a predetermined distance from the right of the crossing, Fig. 1, say about fifteen hundred feet or more, an insulation f is interposed in the rail F, and at a distance of about, say, one hundred and fifty feet nearer the crossing insulations f f are arranged, respectively, in the rails F and G. Section f of rail F thereby becomes isolated. At either side of the crossing insulations G G form an isolated section of rail g in rail G and extending over the crossing. To the left of the crossing insulations 00 y z are provided, similar in location to ff f Section w is thus similar to f, and there are also formed rail-sections g and g in rail G. The rails H H are understood to be correspondingly provided with insulations.
A wire 1 is electrically connected to insulated section f and communicates through wire 3 with an ordinary electric bell J and battery J, back through wires 4 and 2, and thence through track-connector K, the space from rail to rail being understood to be bridged by the wheels and axles of a car as it enters uponthe section. A similar bellline extends from section 00 through wires 1 and 3, bell-wires 4and 2, and thence through the track-connector K. These circuits will be hereinafter termed for convenience the bell-circuits.
The wire 2 is connected to rail-section g and forms a portion of the main operatingcircuit composed of wires 2 and 5, branching at point 5 into two shunts, one connected to the coil of an electromagnet L, and extendin g by wires 6 and 7 to battery J The other shunt is connected to an ordinary circuitbreaker K by wire 8 and is connected by wire 8 to the coil of electromagnet E. The shunts then unite at 7 and extend to the battery and thence by wire 9 to rail F. This circuit will be hereinafter designated for convenience the right-hand main circuit.
The main wire 2 is connected to rail-section g through magnets L and E, and thence to rail F, as before. This circuit may be termed the left-hand main circuit. In both instances the wheels and axles of cars complete the circuit from opposite rails.
The wire 10 is electrically connected to section g and is a portion of a circuit which extends through the coil of magnet M, through wires 11, 6, and 7, battery J and wire 9 to rail F. This circuit may be designated the street or crossing circuit. Operating in connection with this circuit is what I term a local circuit, comprising magnet E,wires 12 and 7 to battery J and wires 9 and 13 through circuit-closer M, circuit-breaker N back to magnet E by wire 14:. The electromagnet L is provided with a pivoted armature Z, carrying at one end a wedge of insu lating material adapted to enter in between the flexible springs of the circuit-breaker K when the armature is attracted and thereby break the circuit of magnet E. It is obvious, therefore, that when any current is passing in'the main circuits, either through lines 2 or 2, it will pass through both shunts for an instant, sufficient to attract the armature of magnet E, after which the circuit in this shunt will be broken and the entire current pass through the shunt of magnet L, keeping its armature continually attracted.
The magnet M is provided with a pivoted armature m, whose free ends are adapted to operate the circuit-closer M and circuitbreaker N, respectively. The construction of these parts is detailed in Fig. 3. The circuit-breaker consists of two flexible plates or springs n a, separated by insulation, but affordin g a path for the current through studs n n on the plates, respectively, and normally in contact. On one of the free ends of the armature a point 72 of insulating material, is secured, so that as the armature is attracted the point will be rocked downward to separate the contact points or studs. The spring at is a continuation of wire 13, while spring a is connected to line 14.
The circuit-closer consists of a vertical weighted rod M, having an arm m, under which the right-hand end, Fig. 1, of the ar-' mature engages. The local circuit is normally open at points 0 0. Upon the rod M is arranged at the proper place a bar 0 of conducting material, whereby as the armature lifts the rod the bar will span the break in the circuit and complete it. In order to clock the rod in its upper position and to release it at the proper time, I provide the rod with a shoulder m in which a spring-pressed arm m engages. In order to throw this arm out of engagement, I provide a plunger m normally kept in a retracted position by a light weight and adapted to be engaged by the end of the armature, whereby the pl unger will be advanced to throw out the arm in". The rod M will then be free to drop by reason of its own gravity. In this connection it will be observed from the arrangement of the parts that when the magnet is excited the circuit breaker is actuated slightly in advance of the circuit-closer and that when it is demagnetized the bar 0 will for an instant span the points after the contact of the studs 92 n thereby momentarily completing the local circuit.
The circuits and operatin g parts being arranged as above set forth, I will now proceed to describe my method and the operation of the gates.
Assuming that a train is' approaching on the upper track from the right, Fig. 2, it will enter the insulated section f and by means of the wheels and axles of the cars will complete the bell-circuit and sound the warningalarin. As soon as the train has reached section g a circuit will be completed through the right hand main circuit, composed of wire 2, the two shunts containing, respectively, magnets L and'E, battery J and wire 9 to rail F, and thence through the axles and wheels forming a bridge connection between the opposite rails. The armature Z will therefore be attracted and the circuit through the other shunt will be broken, but not before the magnet E has become sufficiently energized to attract its armature to allow the weight 0 to drop and thus operate the gatearms in the manner before described.
It is to be noticed that the bell-circuits are so arranged that the bell is ringing continually while the train is within the danger limit on either side of the crossing. When the train is on section the bell is located in a shunt composed of wires 2, 4, 15, and 8 to point 5', where it unites with the main circuit running back to rail F.
When the train has reached the crossing and entered section 9 it will complete the crossing-circuit in a similar manner. The magnet M thereby becomesenergized and remains in that condition as long as there is a truck upon the crossing-section. The armaturemis attracted, breaking the local circuit and electrically bridging the space between points 0 O. The local circuit is therefore completed at one point but previously broken at another. When the last truck of the last car has cleared or passed over section g the crossing-circuit will be broken and magnet M thereby become demagnetized,
whereby its armature will drop and for an instant of time the local circuit will be completed. Magnet E is consequently momentarily excited and the gate mechanism caused to operate so as to raise the gates, as before described. It is to be observed that regardless of the length of the train the gates are not allowed to rise until the last truck has entirely cleared the crossing. It is also to be noticed that the armature of magnet L is still attracted and the shunt through magnet E is broken until the last truck has passed beyond section 00, whereby the weight 0 is kept in its normal position.
As shown in Fig. 2, the set of rails H II of the other track is properly connected in the circuits, so as to permit trains to operate the gate mechanism in precisely the same manner as upon the other track. It will be understood, however, that a train passing on the upper track from left to right, Fig. 2, will operate the gates the same as when going in the opposite direction.
In Fig. 4 I have shown a modified form of circuit in which the mechanism of Fig. 1 may be dispensed with, but in which fluid-pressure is supplied to the gate mechanism in the same way. The rails P P are divided up in sections 19, 29, 19 p and 19 For convenience I have omitted the bell and its circuits, as it will be obvious that a circuit similar to that shown in Fig. 2'may be provided. The section 1) forms part of a circuit composed of wires 16 and 17, through points i) o and a portion of armature p of magnet P wire 18, circuit-breaker P wire 19, through magnet R, wire 20 to battery Q by wire 21, through wires 22, 23, 24, and 25 to rail P in section 19. The circuit of which section 19 forms a part consists of wire 26 from rail P, magnets R and P wires 27 and 21 to battery, thence through wires 22, 23, and 28 to rail P. The circuit in which section 0 is interposed consists of wire 29 from rail P and the same circuit used by section 19, except that it returns to the rail by Wire 30.
The magnet V is provided with a pivoted armature V, having a wedge V of insulating material at one end and adapted to act upon the circuit-breaker P The other end of the armature is provided with a shoulder adapted to be engaged by the free end of a pivoted armature 19 The latter armature electrically bridges the space between the two separated points of buttons '0 c, which are thus connected when the magnet P is demagnetized. The armature V is kept in its normal position (shown in Fig. 4) by means of a light spring 41 which will cause the ends of the two armatures to engage when magnet P is excited. The magnet V is interposed in a high-resistance circuit composed of wires 29 and 17 from railP, Wire 38 to magnet, Wires 39,27, and 21 to battery, and thence by wires 22, 23, 24, and 30 to opposite rail P.
The magnets S and S are arranged close together with their similar poles oppositely disposed. They are provided with a common armature S preferably adjustably secured upon a connecting-rod s, which controls two valves 8 s in a manner similar to the rod a in Fig. 1. The valve 3 in the feed-pipe S is open when the valve 8 in the exhaust-pipe S is closed, and vice versa. These magnets are arranged in independent local circuits, the magnet S being arranged in a circuit composed of wires 31 and 22, battery, wire 32, circuit-breaker T, wire 32, circuit-closer T, wire 33, back to magnet. The circuit of magnet S consists of wires 34 and 22, battery, wire 35, circuit-breaker U, wire 36, circuitcloser U, and wire 37, back to magnet.
It will be understood that the construction of the circuit-closers T and U is practically identical with that detailed in Fig. 3, while their actuation by means of the armatures 7'7" is identically the same. The circuit-breakers P and U are of the ordinary construction and operate in the ordinary way.
Assuming that a train is approaching the crossing which is located at section 19 it will enter upon section 19 and complete the circuit between the rails by means of the wheels and axles. The circuit of this section being thus closed, a current will pass through magnet R and energize it, attracting its armature. The circuit-closer will complete the local circuit of magnet S at one point, but break it at another. As soon, however, as the last truck has cleared section 10 the circuit of that section will be broken and the local circuit momentarily closed, whereby the armatureS will be attracted and reciprocated to the'left, Fig. 4, and thus admit air-pressure to the gatecylinder to lower'the gates.
When the first wheelsenter section 19 the circuit of that section will be completed and the current will pass through magnets R and P The local circuit of magnet S will then be put into proper position'to be completed when the last truck-"clears the crossing or other predetermined point. Simultaneously the magnet P 'is excited and its armature attracted, thereby breaking the circuit between points '0 o. The armature V will then engage armature p and withhold it until magnet V is excited to release the parts, as hereinafter described. When the last truck clears the crossing or passes'from section 29 the local circuit of magnet S" will be'completed for an instant and the magnet willbe momentarily excited, so as to reciprocate armature S to the right, Fig. 4:, whereby the exhaustvalve will be opened and the supply-pipe valve closed to allow the gates to rise; When the train enters section'p, it will complete the circuit of magnet V, which will be energized to attract its armature andthereby release the engaging parts; 'Itis obvious that in this case also a train will properly operate the gates when going in either. direction on the same track, and, furthermore, that the operation by trains running on the other set of rails will be precisely the same. In both of the circuits herein shown I have so arranged the circuits and other parts that a single battery is suflicient for the gate-operating mechanism proper.
It will be understood that the core of .a s0- lenoid may be attached to the arm of a gravity-gate and the current through the solenoid be automatically under the control of the trains. A circuit somewhat similar to that shown in the drawings may be provided for the purpose.
Although Ihave described more or less precise forms and details of construction Ido not intend to be understood as limiting myself thereto, as I contemplate changes in form, proportion of parts, and the substitution of equivalents as circumstances may suggest or render expedient and without departing from the spirit of my invention.
I claim 1. In an automatic railway-gate system, the combination,with gate-operatin g mechanism, of two electrical circuits successively closed by the movements of a car to close and open the gate, and an intervening circuit, also closed by the car, which holds the second circuit open until the entire train has passed a predetermined point.
2. In an automatic railway-gate system,the combination, with gate-operating mechanism, of two electrical circuits successively closed by the movements of a car, electromagnets interposed in the circuits and adapted to con trol the gate-operating mechanism to close and open the gate whenever their respective circuit is closed, and an intervening circuit also closed by the car, which holds the second circuit open until the entire train has passed a predetermined point.
3. In an automatic railway-gate systennthe combination, with gate-operatin g mechanism, of a rail way-track divided into three insulated sections, the second or middle section being located at the roadway or crossing guarded by the gate, and the first and third sections being located on either side of the crossing or second section, said first and third sections being used in connection respectively with the lowering and raising of the gate, two electrical circuits connected respectively to said first and third sections and successively closed by the movements of a car to control the gateoperating mechanism to close and open the gate and an intervening circuit connected to the second or crossing section and also closed by the car, which intervening circuit holds the second circuit open until the entire train has passed a predetermined point.
4. In an automatic railway-gate system,the combination, with gate-operatin g mechanism, of a railway-track divided into three insulated sections, the second or middle section being a crossingsection extending over the road or crossing and the first and third sections being located on either side of the crossing-section, an electrical circuit connected to the first sec tion and permittedto be closed by the movements of a car, an electromagnet interposed in said circuit and adapted to permit the gateoperating mechanism to lower the gate, a second electrical circuit connected to the third section and permitted to be closed by the movements of the car, an electromagnet interposed in said last-named circuit and, when closed, adapted to permit the gate-operating mechanism to open the gate, and an intervening circuit connected to the second section of track and also closed by the car, which intervening circuit holds the second circuit open until the last truck of the car has passed 01f from the crossing or second section.
5. In an automatic railway-gate system,the combination of a railway-track having insulated sections, an electromagnet arranged in a normally open circuit which is permitted to be closed as a car enters asection, mechanism under control of the eleotromagnet for actuating the gates whereby as the magnet is excited the gate-arms will be lowered, a second electromagnet arranged in a normally open circuit and permitted to be closed only When a car leaves another section at or near the crossing, and a connection with the gate mechanism and under the control of the second electromagnet whereby as the latter is excited the gate mechanism will be operated to raise the gate-arms, but only after the last truck of the car has cleared the crossing or other predetermined point.
6. In an automatic railway-gate system,the combination of a magnet arranged in a normally open circuit, means for closing the circuit by the movement of a car upon the railway-track, mechanism for actuating the gates, a connection with the gate mechanism, and under the control of the magnet, whereby as the latter is excited the gate-arms will be lowered, a second magnet arranged in a normally open circuit, means for closing the same as a car reaches the crossing, a third magnet arranged in a local circuit and under the control of the second magnet, whereby as the second magnet is excited and then is demagnetized as the last truck clears the crossing or other point the local circuit will be momentarily completed, and a connection with the gate mechanism and under the control of the third magnet whereby as the latter is excited the gate-arms will be raised.
7. I11 an automatic railway-gate system,the combination of a railway-track having insulated sections f and 9 an electrical circuit normally open at the rails, magnets L and E interposed therein, but each arranged in its own shunt, a circuit-breaker in the shunt of magnet E, a connection between thearmature of magnet L and the circuit-breaker whereby as magnet L is excited the shuntcircuit of magnet E will be broken but only after the momentary energizing of the latter magnet, mechanism under control of magnet E for actuating the gates whereby as a car enters section f and completes the circuit magnet E will be excited and the gate-arms lowered, an electrical circuit normally open and connected with section 9 located at or near the crossing, a magnet M arranged in this circuit, a magnet E arranged in a normally open local circuit, and a circuitbreaker and a circuit-closer arranged in the local circuit and under control of magnet M whereby as a car enters section g the circuit will be completed and magnet M excited to operate the circuit-breaker and closer, thereby causing the local circuit to be momentarily closed as the last truck of the car leaves section g and a connection with the gate mechanism under control of magnet E whereby as the same is excited thus momentarily the gatearms will be raised.
JOHN STUART BIGGAR. YVitnesses:
SAMUEL E. HIBBEN, ELsIE N EMETT.
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