US1059828A - System for vehicle control. - Google Patents

System for vehicle control. Download PDF

Info

Publication number
US1059828A
US1059828A US72385312A US1912723853A US1059828A US 1059828 A US1059828 A US 1059828A US 72385312 A US72385312 A US 72385312A US 1912723853 A US1912723853 A US 1912723853A US 1059828 A US1059828 A US 1059828A
Authority
US
United States
Prior art keywords
alarm device
signal
train
vehicle
track
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US72385312A
Inventor
John T Cade
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
FEDERAL SIGNAL Co
FED SIGNAL Co
Original Assignee
FED SIGNAL Co
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by FED SIGNAL Co filed Critical FED SIGNAL Co
Priority to US72385312A priority Critical patent/US1059828A/en
Application granted granted Critical
Publication of US1059828A publication Critical patent/US1059828A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61LGUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L3/00Devices along the route for controlling devices on the vehicle or vehicle train, e.g. to release brake, to operate a warning signal
    • B61L3/02Devices along the route for controlling devices on the vehicle or vehicle train, e.g. to release brake, to operate a warning signal at selected places along the route, e.g. intermittent control simultaneous mechanical and electrical control
    • B61L3/08Devices along the route for controlling devices on the vehicle or vehicle train, e.g. to release brake, to operate a warning signal at selected places along the route, e.g. intermittent control simultaneous mechanical and electrical control controlling electrically

Definitions

  • This invention relates to vehicle or train control systems and has for its object to eliminate certain dangers to railway traffic which have lately impressed themselves upon I the-mindset the public and those actively interested in the installation apparatus of this character.
  • the control of the train is nottaken from the engine driver but provision is made to make him exercise increased care against proceeding when travel is dangerous without full knowledge and realization of his act. It will be understood that travel is dangerous when conditions are such as those now usually indicated by the warning condition of a signal.
  • the automatic stop is eliminated and in its place there is provided a special alarm device de-' signed to be automatically operated whenever the engine driver proceeds when travel is dangerous or when he enters a danger Zone of the track, unless, having noted the danger condition of the track, he performs some act that will forestall the operation of the alarm device after having retarded or brought his car or train under control.
  • This alarm device is distinct in its action or appeal from that of the bell whistle or other signal usually carried on a train or vehicle, being designed and arranged to attract the attention of the occupants of the vehicle or train other than the vehicle operators, such as the engine driver and fireman of a steam locomotive or the motorinan of an electric car or train.
  • the alarm de-' vice is also preferably designed and arranged to attract the attention of such operators of the vehicle or train in addition to that of the occupants, such as the passengers and such as the train crew other than the operators.
  • the control of the train is left with the engine driver, but he is induced to exercise increased watchfulness and is made to realize the consequences of his act when entering or about to enter a danger zone of the track.
  • a signal is employed to indicate to the engine driver when travel is dangerous and it is arranged to give its warning at the entering end of a track zone when travel in such zone is dangerous.
  • the signal with which the alarm device is associated may be a full'stop or a cautionary signal. In either case, when the signal gives its warning indi cation, it is to; be understood that the track zone guarded by the si al is dangerous or is a danger zone as these terms are herein used.
  • the invention may be embodied in various forms. It is not restricted to any special type of alarm device nor any special type of signal. This alarm device may be stationed on the trackway or it may be located on the'engine or at otl1'er ⁇ points on the train. Nor is the,invention to be restricted to any special means for controlling or operating the signal or alarm device.
  • Figure l is a diagrammatic representation of the system.
  • Fig. 2 isa side elevation showing a car on'which is mounted a treadle for cutting out the alarm device and a lever operating to retard the car and controlling the treadle.
  • 1, 2 and 3 are track sections insulated from each other, track sections 1 and 2 being provided with the usual track circuits in the former of which is the track magnet 4, and in the latter of which is the track magnet 5.
  • the 6 is a signal of the semaphore type located on the trackway at the entering end 'of track section 1 and arranged to stand normally at safety.
  • the signal is shown as operated by a solenoid 91:01 other type of motor, the circuit of which is normally closed and extends from generator 7, through wire 8, solenoid 9, wire 10, contact point -11, contact finger 12 of magnet 14, and wire 15 back to generator 7."
  • 16 and 17 are two contact rails on the trackway connected, respectively, by wires 18 and 19 with contact points 20 and 21 which are normally in electrical connection by means of the contact.22 carried on the blade of the semaphore 6.
  • Magnet 23 is normally energized by a circuit which ineludes generator 7, wire 24, contact rail 17,
  • thiscircuit is elosed when the semaphore is in safety position and broken when the semaphore is in danger position.
  • 27 is an alarm device preferably located on the trackway in proximity to the semaphore 6. It may be embodied in various forms and it may address itself to'the intelligence in any suitable manner, audible or other- 35 of magnet 23, wire 36, contact point 37,
  • This circuit is normally open at three points, namely, at contacts 29, 30, at contact finger 35 and at-contaet finger 38.
  • Contact rail 17 is connected with wire 25 through wire40, 'contact finger 41 of magnet 5, contact 42, wire 43, contact finger 44 of magnet 23, contact point 45 and wire 56.
  • the 46, 47 and 48,. are three 'cars of a train traveling on the track in the direction of the arrow.
  • a trcadle 49 mounted on the car 46 is a trcadle 49 arranged to operate a shoe 50 capable of bridging the contactrails 16 and 17 and thereby connect them electrically together.
  • an arm 51 Connected with the treadle is an arm 51 which operates a link 52 having a' slot through which passesa pin on the lever 54.
  • This lever controls the motive power or brakes, or both, of the vehicle or train and mustbe first pulled back to re tard the vehicle or train before the shoe may be depressed.
  • the shoe 44 is normally elevated abovethe contact rails and is de-.
  • lever 54 may be operated independently of, or without depressing, the shoe 44.
  • the alarm device does not operate because when the train reaches tracksection 2, it merely deenergizes magnet ,5 and closes at contact finger 38 only one of the three breaks normally in the circuit of the alarm device 27 heretofore pointed out, and because whenlhe train passes on to track section 1, it merely deenergizes track magnet 4, thereby breaking the signal circuit and permitting the semaphore to drop to danger position.
  • the train has passed beyond track section 1 and the track portion guarded by the signal, the signal returns to safety position with the circuits and devices in normal condition.
  • the alarm device is cut out and without having depressed the shoe 50, will pass on to track section 2.
  • the magnet '23 will bc-deenergized because the semaphore 6 has broken the circuit of this magnet at contacts 20, 21 and 22 by its movement to danger position. This causes two of the breaks in the circuit of the alarm dev ce, namely, the break at contact finger and the break at contacts 29, 30. hen,
  • the invention may be associated with a signal standing normally at danger as well as to one standing at satelvf also with a signal located on the vehicle as well as on the trackway and also with a'signal whose indication is given otherwise than by changes in position.
  • danger condition of a signal or semaphore means a cantionary or any condition other than safety
  • a vehicle control system the combination of a signal; an alarm device operable when the signal is in a predetermined condition of indication; vehicle controlled means for operating the alarm device when the signal is in saidcondition of indication; means for preventing the operation of the alarm device; and provisions for retarding the vehicle and arranged to control said last mentioned means.
  • the combi- 30 nation of a signal located on the trackway an alarm device operable when the signal is in a predetermined condition of'indicationy vehicle cimtrolled means for operating the alarm device when the signal isin'said condition of indication; means for preventing the operation of the alarm device;and pro: "isions for retarding the vehicle and arranged to control said last mentioned means.
  • a signal guarding a portion of the track a track circuit controlling said slgnal; an 'alarm device operable when the v slgnalis in a predetermined condition of 'inv dicat o'n; a tack circuiticontrollmg'said alarm device; means for preventing the operation of the alarm device; and provisions for retarding the vehicle and arranged to control said last mentionedmeans,
  • a vehicle control system the comhination of an alarm device distinct in its action from that of the signals usually carried on a vehicle or train and designed and arranged to-attlact the aflcntionof occupants 1 5 of the vehicle or train other than the operators thereof; vehicle conlrollcd means for operating the alarm device; means on the vehicle for preventing the operation of the alarm device: and provision.-; for retarding the vehic e and arranged to control said last mentioned means.
  • the combination ot'an alarm device; vehicle controlled means for operating the alarm device; means on the vehicle for preventing the operation of the alarm device; provisions-for ['(ltill'(ling the vehicle and arranged to controlsaid lnsl mentioned means; and a signal controlling the operation of the alarm d( vice.
  • a. vehicle control system the combination of an alarm device distinct in its action from that of the signals usually carried ona vehicle or train and designed and arranged to attract the attention of occupants of the vehicle or train other than the operators thereof; vehicle controlled means for operating the alarm device; means'for preventing the operationof the alarm device; and provisions for retarding the vehicle and arranged to control said last mentioned means.
  • a signal guarding a ortion of the track a track circuit co'ntro ing said signal; an alarm device operable when the signal is in a predetermined condition of indication; a track circuit controllin said alarm device; means for preventing t e operation of the alarm device; and provisions for retarding the vehicle and arranged to control said last mentioned means.

Description

J T. GADB. SYSTEM FOR VEHICLE CONTROL.
APPLICATION FILED OUT 4 Patented Apr. 22, 1913.
JOHN T. CADE, OF ARCOLA, NEW
JERSEY, ASSIGNOR TO FEDERAL SIGNAL COMPANY,
A CORPORATION OF NEW YORK.
SYSTEM FOR VEHICLE CONTROL.
Specification of Letters Patent.
Patented Apr. 22, 1913.
Application filed October 4, 1912. Serial No. 723,853.
T o alf'whom it may concern Be it known that I, JOHN T. CADE, a citizen of the United States, and a resident of Arcola, county of Bergen, and State of New Jersey, have invented certain new and use ful Improvements in Systems for Vehicle Control, of which the following is a specification.
This invention relates to vehicle or train control systems and has for its object to eliminate certain dangers to railway traffic which have lately impressed themselves upon I the-mindset the public and those actively interested in the installation apparatus of this character.
Recently it has been especially realized that many accidents upon railways are due to the fact thatengine drivers, for one reason and another, pass the ordinary semaphore signal while in its danger position in disregard of traffic regulations. It is found that such action of engine drivers is frequently due less to a voluntary disregard of the signal than to a failure to note or realize its danger indication. Heretofore, it has been proposed to meet this condition by providing train stops to positively and automaticall; stop the train when the engine driver passes or attempts to pass the signal in the danger or stop position. But a train stop is objectionable for reasons peculiar to of systems and .itself. In the first place it takes from the engine driver his own control of his train under certain conditions and makes him liable to rely upon the automatic stop instead of himself to avoid accidents. This tends to lessen that feeling of responsibility, watchfulness and care which it is essential topreserve in the engine driver. Furthermore, the automatic stop is not well adapted to efficient conduct of traffic where such traffic is carried on under the usual widely varying conditions of ordinary railway operation. A signal sometim's stands at danger when it is desirable for traffic reasons that it be passed if this is. done with full realization by the engine driver of his act. A stoppage of the train under such conditions by an automatic stop would serve no useful purpose but "Ollld be a hindrance to trafiic.
In the present invention the control of the train is nottaken from the engine driver but provision is made to make him exercise increased care against proceeding when travel is dangerous without full knowledge and realization of his act. It will be understood that travel is dangerous when conditions are such as those now usually indicated by the warning condition of a signal. In accordance with this invention, therefore, the automatic stop is eliminated and in its place there is provided a special alarm device de-' signed to be automatically operated whenever the engine driver proceeds when travel is dangerous or when he enters a danger Zone of the track, unless, having noted the danger condition of the track, he performs some act that will forestall the operation of the alarm device after having retarded or brought his car or train under control. If he has noted the danger to travel, on the track ahead, and finds it advisable to proceed, notwithstanding, he is at liberty to do so provided he performs some act that will cut out the alarm device from operation after he has retarded or brought his car or train under control. But if, with inattention and lack of watchfulncss, he proceeds when travel is dangerous or into the danger zone, he will fail to attend to the cutting out of the alarm device and it will operate and thereby cause others, and preferably him also, to realize what is taking place. The cutting out or forestalling the operation of the alarm device is effected through preventive means under the control of other provisions which, when operated, serve to retard the vehicle or train. This alarm device is distinct in its action or appeal from that of the bell whistle or other signal usually carried on a train or vehicle, being designed and arranged to attract the attention of the occupants of the vehicle or train other than the vehicle operators, such as the engine driver and fireman of a steam locomotive or the motorinan of an electric car or train. The alarm de-' vice is also preferably designed and arranged to attract the attention of such operators of the vehicle or train in addition to that of the occupants, such as the passengers and such as the train crew other than the operators. Thus the control of the train is left with the engine driver, but he is induced to exercise increased watchfulness and is made to realize the consequences of his act when entering or about to enter a danger zone of the track.
In the. preferred arrangement a signal is employed to indicate to the engine driver when travel is dangerous and it is arranged to give its warning at the entering end of a track zone when travel in such zone is dangerous. It isobvious that the signal with which the alarm device is associated may be a full'stop or a cautionary signal. In either case, when the signal gives its warning indi cation, it is to; be understood that the track zone guarded by the si al is dangerous or is a danger zone as these terms are herein used.
The invention may be embodied in various forms. It is not restricted to any special type of alarm device nor any special type of signal. This alarm device may be stationed on the trackway or it may be located on the'engine or at otl1'er \points on the train. Nor is the,invention to be restricted to any special means for controlling or operating the signal or alarm device.
The invention is shown in one of its various embodiments in the accompanying drawings.
Figure l is a diagrammatic representation of the system. Fig. 2 isa side elevation showing a car on'which is mounted a treadle for cutting out the alarm device and a lever operating to retard the car and controlling the treadle.
- Referring now to this particular embodiment of the invention, as shown in the drawings, 1, 2 and 3 are track sections insulated from each other, track sections 1 and 2 being provided with the usual track circuits in the former of which is the track magnet 4, and in the latter of which is the track magnet 5.
6 is a signal of the semaphore type located on the trackway at the entering end 'of track section 1 and arranged to stand normally at safety. The signal is shown as operated by a solenoid 91:01 other type of motor, the circuit of which is normally closed and extends from generator 7, through wire 8, solenoid 9, wire 10, contact point -11, contact finger 12 of magnet 14, and wire 15 back to generator 7."
16 and 17 are two contact rails on the trackway connected, respectively, by wires 18 and 19 with contact points 20 and 21 which are normally in electrical connection by means of the contact.22 carried on the blade of the semaphore 6. Magnet 23 is normally energized by a circuit which ineludes generator 7, wire 24, contact rail 17,
to which it is, connected, wire 19, contacts 2], 22 and 20, wire 18, contact rail 16, wire 25, connected 'with contact rail 16, magnet 23, wire 26 back to generator 7. It will be seen that thiscircuit is elosed when the semaphore is in safety position and broken when the semaphore is in danger position. 27 is an alarm device preferably located on the trackway in proximity to the semaphore 6. It may be embodied in various forms and it may address itself to'the intelligence in any suitable manner, audible or other- 35 of magnet 23, wire 36, contact point 37,
contact finger 38 of track magnet 5 and wire 39 back to generator 7. This circuit is normally open at three points, namely, at contacts 29, 30, at contact finger 35 and at-contaet finger 38. Contact rail 17 is connected with wire 25 through wire40, 'contact finger 41 of magnet 5, contact 42, wire 43, contact finger 44 of magnet 23, contact point 45 and wire 56.
46, 47 and 48,. are three 'cars of a train traveling on the track in the direction of the arrow. Mounted on the car 46 is a trcadle 49 arranged to operate a shoe 50 capable of bridging the contactrails 16 and 17 and thereby connect them electrically together. Connected with the treadle is an arm 51 which operates a link 52 having a' slot through which passesa pin on the lever 54. This lever controls the motive power or brakes, or both, of the vehicle or train and mustbe first pulled back to re tard the vehicle or train before the shoe may be depressed. The shoe 44 is normally elevated abovethe contact rails and is de-.
signed to be depressed into contact there withby the engine driver on the car 46 but he is unable to perform this act until the lever 54 has been pulled back to retard the car. It will be seen that the lever 54 may be operated independently of, or without depressing, the shoe 44.
The operation of the system is as follows:
\Vhen the train approaches and passes the semaphore 6 while the semaphore is in safety position, the alarm device does not operate because when the train reaches tracksection 2, it merely deenergizes magnet ,5 and closes at contact finger 38 only one of the three breaks normally in the circuit of the alarm device 27 heretofore pointed out, and because whenlhe train passes on to track section 1, it merely deenergizes track magnet 4, thereby breaking the signal circuit and permitting the semaphore to drop to danger position. When .the train,has passed beyond track section 1 and the track portion guarded by the signal, the signal returns to safety position with the circuits and devices in normal condition. ,If the signal is in.danger position and thci' engine driver, having noted this fact, desires to pass the signal notwithstanding its danger indication, he must first pull back his lever 54 to bring his train under control and thereby release his treadle. \Vhen the treadlc has been thus released, the engine driver then depresses the shoe 50 into connection with contact rails 16 and 17. This closes the circuit of the magnet '23. which -was broken at contacts 20, 21 and 22 when the signal moved from safety position, and thereby keeps the circuit of the alarm device open at contact finger 35. lVhen the train proceeds on to track section 2, t deenergizes track magnet 5 and drops contact fingers 38 and 41. Magnet 23 is so constructed as. to have a slow release so that, when the train passes off of section 3 and on to track section 2 andbcyond contact rails 16 and 1?, contac finger *1 will have dropped before contact fingers and. 44- are able to drop. By this arrangement, magnet 23 remains energized when the train is on track section 2 and the alarm device is cut out by the 'break in its circuit at contact finger 35 and remains cut out. When the train is on track section 2, the circuit of magnet may be traced from generator 7, through wire 24, contact rail 17, wiredO, contact finger 41, contact point 42, wire 43, contact finger 44, contactpoint 45, wire 56, magnet 23, wire 26 back to generator 7. Thus, the operation of the alarm device may be prevented bythe action of the engine driver after he has retarded his train. If, however, the signal isat danger and the engine driver fails-to note its indication, he will fail to see ,that
' the alarm device is cut out and without having depressed the shoe 50, will pass on to track section 2. Under this situation, the magnet '23 will bc-deenergized because the semaphore 6 has broken the circuit of this magnet at contacts 20, 21 and 22 by its movement to danger position. This causes two of the breaks in the circuit of the alarm dev ce, namely, the break at contact finger and the break at contacts 29, 30. hen,
therefore, the tram having passed on to track section 2 deiinergvzes track magnet 5,
. and drops contact finger 38, it closes the remaining break in the circuit of the alarm device and the latter is set in operation. Thus the negligent act of the engine driver is; known to other persons on the train who may oper rte the engine'whistlc or apply this emergency brake. It is'th'is possibility of thus set-ting the-alarnr device in operation that is calculated to make the engine. driver attentive and watchful of his signals so that he" may not unknowingly pass a signal at danger position or enter a danger xone.
The invention may be associated with a signal standing normally at danger as well as to one standing at satelvf also with a signal located on the vehicle as well as on the trackway and also with a'signal whose indication is given otherwise than by changes in position.
The term danger condition of a signal or semaphore, as herein shown, means a cantionary or any condition other than safety,
1. In a vehicle control system, the combination of a signal; an alarm device operable when the signal is in a predetermined condition of indication; vehicle controlled means for operating the alarm device when the signal is in saidcondition of indication; means for preventing the operation of the alarm device; and provisions for retarding the vehicle and arranged to control said last mentioned means.
2. In a vehicle control system, the combi- 30 nation of a signal located on the trackway; an alarm device operable when the signal is in a predetermined condition of'indicationy vehicle cimtrolled means for operating the alarm device when the signal isin'said condition of indication; means for preventing the operation of the alarm device;and pro: "isions for retarding the vehicle and arranged to control said last mentioned means.
3. In a railway control system, the combination of a signal guarding a portion of the track; a track circuit controlling said slgnal; an 'alarm device operable when the v slgnalis in a predetermined condition of 'inv dicat o'n; a tack circuiticontrollmg'said alarm device; means for preventing the operation of the alarm device; and provisions for retarding the vehicle and arranged to control said last mentionedmeans,
4. In a railway control-system, the c'ombination of a signal located on the trackway and guarding a portion of the track; a track circuit controllingsald signal; an alarm device operable when the signal is in apredetermiued condition ofindication; a track circuit controlling said alarm device; means for preventing the operation of the alarm device; and provisions for retarding the vehicle and arranged tq control said last mentioned means.
5. In a vehicle control system, the comhination of an alarm device distinct in its action from that of the signals usually carried on a vehicle or train and designed and arranged to-attlact the aflcntionof occupants 1 5 of the vehicle or train other than the operators thereof; vehicle conlrollcd means for operating the alarm device; means on the vehicle for preventing the operation of the alarm device: and provision.-; for retarding the vehic e and arranged to control said last mentioned means.
6. In a vehicle control system, the combination ot'an alarm device; vehicle controlled means for operating the alarm device; means on the vehicle for preventing the operation of the alarm device; provisions-for ['(ltill'(ling the vehicle and arranged to controlsaid lnsl mentioned means; and a signal controlling the operation of the alarm d( vice.
7. In a. vehicle control system, the combination of an alarm device distinct in its action from that of the signals usually carried ona vehicle or train and designed and arranged to attract the attention of occupants of the vehicle or train other than the operators thereof; vehicle controlled means for operating the alarm device; means'for preventing the operationof the alarm device; and provisions for retarding the vehicle and arranged to control said last mentioned means.
8. In a vehicle control system, the combination of an alarm device located on the trackway; vehicle controlled means for operatmg the alarm device; means for preventing the operation of the alarm device;-
alarm'device; and provisions for retarding .the vehicleoperable independently of an arranged to control said last. mentioned means.
10. In a vehicle control system, the combination of an alarm device located on the trackway; vehicle controlled means for operating the alarm device; means on the vehiole for preventing the operation of the alarm device; and provisions for retarding the ve- I hicle and arranged to control said last mentioned means. i
11. In a railway control system, the combination of a signal guarding a ortion of the track; a track circuit co'ntro ing said signal; an alarm device operable when the signal is in a predetermined condition of indication; a track circuit controllin said alarm device; means for preventing t e operation of the alarm device; and provisions for retarding the vehicle and arranged to control said last mentioned means. 7
In testimony whereof, I have signed my name to this specification, in the presence of two subscribing witnesses.
- 7 JOHN T. CADE. \Vitnesses:
Ina G. GILMORE, WORTHINGTON CAMPBELL.
US72385312A 1912-10-04 1912-10-04 System for vehicle control. Expired - Lifetime US1059828A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US72385312A US1059828A (en) 1912-10-04 1912-10-04 System for vehicle control.

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US72385312A US1059828A (en) 1912-10-04 1912-10-04 System for vehicle control.

Publications (1)

Publication Number Publication Date
US1059828A true US1059828A (en) 1913-04-22

Family

ID=3128077

Family Applications (1)

Application Number Title Priority Date Filing Date
US72385312A Expired - Lifetime US1059828A (en) 1912-10-04 1912-10-04 System for vehicle control.

Country Status (1)

Country Link
US (1) US1059828A (en)

Similar Documents

Publication Publication Date Title
JP4084491B2 (en) Vehicle abnormal impact reporting device
US1059828A (en) System for vehicle control.
US1140356A (en) System for vehicle control.
US1231846A (en) Vehicle-control system.
US1064441A (en) System for vehicle control.
US1202266A (en) Vehicle control system.
US1533632A (en) Automatic derail signal
US1316263A (en) Train-control system
US1187586A (en) Electric railway-signal and appertaining mechanism.
US1082095A (en) Train control and signal system for double-track railways.
US1068614A (en) Automatic block system.
US1759404A (en) Train control
US1601427A (en) Continuous inductive train control
US605941A (en) Electric block-signal system for railways
US855727A (en) Electric signaling system.
US1789274A (en) Automatic train-control system
US928273A (en) Block system for railways.
US1744012A (en) Automatic train-control system of the permissive type
US560359A (en) Device for railway signaling or other purposes
US1200270A (en) Automatic car-stop.
US1703844A (en) Train control
US1121254A (en) System for operating railroad traffic.
US1155478A (en) Safety apparatus for railway-trains.
US1767578A (en) Automatic train-control system
US756957A (en) Electric safety system for railways.