US3876171A - Railway signalling system - Google Patents

Railway signalling system Download PDF

Info

Publication number
US3876171A
US3876171A US341664A US34166473A US3876171A US 3876171 A US3876171 A US 3876171A US 341664 A US341664 A US 341664A US 34166473 A US34166473 A US 34166473A US 3876171 A US3876171 A US 3876171A
Authority
US
United States
Prior art keywords
signal
electro
antenna
inductor
coil
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
US341664A
Inventor
Michael S Birkin
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.)
British Railways Board
Original Assignee
British Railways Board
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 British Railways Board filed Critical British Railways Board
Priority to US341664A priority Critical patent/US3876171A/en
Application granted granted Critical
Publication of US3876171A publication Critical patent/US3876171A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B61—RAILWAYS
    • B61L—GUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L3/00—Devices along the route for controlling devices on the vehicle or train, e.g. to release brake or to operate a warning signal
    • B61L3/02—Devices along the route for controlling devices on the vehicle or train, e.g. to release brake or to operate a warning signal at selected places along the route, e.g. intermittent control simultaneous mechanical and electrical control
    • B61L3/08—Devices along the route for controlling devices on the vehicle or train, e.g. to release brake or to operate a warning signal at selected places along the route, e.g. intermittent control simultaneous mechanical and electrical control controlling electrically
    • B61L3/12—Devices along the route for controlling devices on the vehicle or train, e.g. to release brake or to operate a warning signal at selected places along the route, e.g. intermittent control simultaneous mechanical and electrical control controlling electrically using magnetic or electrostatic induction; using radio waves
    • B61L3/121—Devices along the route for controlling devices on the vehicle or train, e.g. to release brake or to operate a warning signal at selected places along the route, e.g. intermittent control simultaneous mechanical and electrical control controlling electrically using magnetic or electrostatic induction; using radio waves using magnetic induction

Definitions

  • a railway signalling system comprises a permanent magnet positioned on a railway track at a point preceding a multi-aspect signal, an electro-inductor and an antenna positioned adjacent the magnet, means for energizing the electro-inductor with a dc supply and the antenna with high frequency signal in dependence upon the current aspect of the signal.
  • a detector is carried by a railway vehicle for detecting the fields produced by the magnet, electro-inductor and antenna and provides a warning to a driver of the train corresponding to the current aspect of said signal.
  • the present invention relates to an improved railway signalling system of the kind in which train borne indicators provide an automatic warning of the signal aspect to the driver of the train.
  • the indicators are controlled by devices located between the rails of the track.
  • a railway signalling system comprising a permanent magnet positioned on a railway track at a point preceding a multi-aspect signal, an electro-inductor and an-antenna means positioned adjacent said magnet, means for energizing said electro-inductor with a dc. supply and said antenna means with high frequency signal in dependence upon the current aspect of the signal, detector means carried by a railway vehicle fordetecting the fields produced by said magnet, electro-inductor and antenna means and to provide a warning to a driver of the train corresponding to the current aspect of said signal.
  • FIG. 1 is a plan view of a length of railway track in which the track mounted transmitting portion of a signalling system is positioned between the rails.
  • FIG. 2 is a schematic diagram of the detection and cab signalling equipment carried by the train.
  • FIGS. 3 and 4 are circuit diagrams of two possible arrangements of the electro-inductor and a track coil mounted on the railway track.
  • FIG. 5 is a circuit diagram of an alternative embodiment for the track mounted antenna.
  • a permanent magnet and an electro-inductor 11 are laid between the rails 12 of a railway track.
  • This combination of a permanent magnet and an electro-inductor forms the basis of a known railway automatic warning system.
  • Colour light railway signals commonly have four aspects, namely one green, two yellow and one red. The green aspect alone is lit to indicate that the line ahead is clear, and in this situation the electro-inductor is not energized by a suitable d.c. source.
  • Detecting equipment carried by a train detects the magnetic fields of both the permanent magnet and the electro-inductor and when the latter is energized and its field is detected, equipment carried by the train automatically registers that a signal with a green aspect is being approached and consequently no braking action is required by the driver.
  • the electromagnet When however the two cautionary aspects, single or double yellow or the red stop aspect is lit, the electromagnet is not energized.
  • the detecting equipment carried by the train registers this fact and operates an appropriate warning indicator on the train and unless appropriate action is taken by the driver, operates the train brakes.
  • a loop antenna 13 of suitable size and of one or more turns is laid between the rails 12 adjacent the magnet and electro-inductor.
  • the electro-inductor 11 is fed from a rectified a.c. supply and the antenna 13 is fed from an appropriate transmitter as will be described below, and the two elements can be energized or not as required as will be described.
  • the table below shows how each of the two elements 11 and 13 is energized in dependence' upon the aspect of the signal being approached by the train.
  • the detect-' ing equipment activates an appropriate warning in the drivers cab which in certain cases must be acknowledged by the driver.
  • the equipment could be used to give suitable indication such as numerical indication of speed permitted.
  • the train equipment detects first the permanent magnet 10 and then the energized-electro inductor 11, the antenna 13 being unenergized.
  • the train equipment detects first the permanent magnet-10, then the antenna 13 which' is energized with an HR, carrier, the electro inductor 11 being unenergized.
  • a detector 14 carried by the train detects the presence of the permanent magnet 10 and actuates a logic unit 15 which operates a display, alarm and acknowl edgment unit.
  • the detection of the presence of a permanent magnet sets the logic unit 15 into a state such that if neither an energized electro-inductor 11 nor an energized antenna 13 are detected within a certain time interval, an audible warning sounds on a horn 1 6.
  • the driver may acknowledge the warning by pressing an acknowledgment button 17 which is illuminated by the unit 15, which will cause the horn 16 to cease; if the driver doesv not do this, the train brakes will be automatically applied.
  • a receiving aerial 19 carried by the train detects a carrier signal from the energized track loop antenna 13 within the stated time interval, in place of a detection induc- 3 bythe detector 14 of an energized electro-inductor, this signal is fed to a selector relay 20 via a band-pass filter 2i, amplifier 22 ahd detector 23, causing relay contacts 24 to switch over and connect an acknowledgrnentbutton 25 to the logic unit lSQ
  • the logic unit 5 causes'a'n audible warning to sound on the horn 16 and the driver must acknowledge this warning of a double yellow aspect by means of the press button 25 which is illuminated by unit 15, otherwise the brakes will be automatically applied.
  • the relay ' is reset by a signalfrom the logic unit 15 when the detector 14 detects the presence of the next permanent magnet 10, causing the logic unit 15 to again be connected to the acknowledgment button 17.
  • the display unit is more complex than that shown in FIG. 2, and ineludes a facility for the acknowledgment and display of agreen aspect.
  • the logic unit 15 would require enhancing also, so that a second time interval is available, if bothithe permanent magnet 10 and electro inductor 11 have been detected, within which the presence ofa carrier signalfr om the loop antenna 13 may be detected in order that the train equipment might differentiate betweenthe green and 5th aspect conditions.
  • FIGS illustrates an alternative arrangement in which a carrier signal gen'erator34 consisting of a power supplyirni-t '35 on oscillator 36 and a power amplifier 37 is' p os'iti oned closely adjacent to the antenna 13, being coupled to it via a matching transformer 38.
  • a carrier signal gen'erator34 consisting of a power supplyirni-t '35 on oscillator 36 and a power amplifier 37 is' p os'iti oned closely adjacent to the antenna 13, being coupled to it via a matching transformer 38.
  • relay contacts 27 in the supply leads 26 for the electro inductor l1 closeto "energize the electro l inductor 11 when the signal aspect is green and when it is desired to exhibit the 5th aspect.
  • a ferrite rod antenna of known'eonstruction can be employed to transmitth'e carrier signal to the pick-up coil 19.
  • a frame antenna which may be of prin td circuit constructiom could be used.
  • This frame antenna could, be incor'poratedinto' the structure of the housing forthe generatorunit 34.
  • the 5th aspect referred to in the Specification in which both the electro-inductor 11 and the antenna 13 are energized is intended for use with very high speed trains in order to extend the signalling range.
  • Very high speed trains clearly require a considerably longer distance in'which to brake from maximum speed'to rest than do trains whose maximum speed is considerably less.
  • the 5th signal aspect is intended for use in such situations, to indicate to the driver of a very highspeed train that'it is safefor'the train to travel at its maximum speed since the track ahead is clear for at least the necessarymaximum braking distance.
  • a railway signalling system comprising:
  • detector means carried by a railway vehicle for detecting the fields produced by said magnet, by said electro-inductor and by said antenna means to provide a warning to adriver of the train corresponding to the present aspect of saidsignal, said detector means including a first and second in- .ductive pick-upcoil, said first pickup coil being adapted to detect the static magnetic field produced by the permanent magnetand by said electro-inductor, and said second pick-up coil being adapted to detect the high frequency alternating V magnetic field produced by said antenna, I said first coil being connected by way of a logic unit to a first and second alarm means, first acknowledgement means for said second alarm means, saidsecond coil being connected to a relay coil whose contacts connect said logic unit to a second alternative acknowledgment means for said second alarm means, said logic unit in response to detection by said first pick-up coil of a signal from said permanent magnet along actuating said second alarm means to thereby require the train driver to operate said firstacknowledgment means

Landscapes

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

Abstract

A railway signalling system comprises a permanent magnet positioned on a railway track at a point preceding a multi-aspect signal, an electro-inductor and an antenna positioned adjacent the magnet, means for energizing the electro-inductor with a d.c. supply and the antenna with high frequency signal in dependence upon the current aspect of the signal. A detector is carried by a railway vehicle for detecting the fields produced by the magnet, electro-inductor and antenna and provides a warning to a driver of the train corresponding to the current aspect of said signal.

Description

United States Patent [1 1 Birkin [111 3,876,171 [451 Apr. s, 1975 RAILWAY SIGNALLING SYSTEM [75] Inventor: Michael S. Birkin, London, England [73] Assignee: British Railways Board, London,
England [22] Filed: Mar. 15, 1973 [211 App]. No.: 341,664
OTHER PUBLICATIONS Davies et 211., Bournemouth Line Cab Signalling, Railway Gazette, July 18, 1969, pp. 545, 546, 549.
Primary Examiner-Robert S. Ward, Jr.
Assistant E.\'aminerReinhard J. Eisenzopf Attorney, Agent, or Firm'-'Pol1ock, Philpitt & Vande Sande [57] ABSTRACT A railway signalling system comprises a permanent magnet positioned on a railway track at a point preceding a multi-aspect signal, an electro-inductor and an antenna positioned adjacent the magnet, means for energizing the electro-inductor with a dc supply and the antenna with high frequency signal in dependence upon the current aspect of the signal. A detector is carried by a railway vehicle for detecting the fields produced by the magnet, electro-inductor and antenna and provides a warning to a driver of the train corresponding to the current aspect of said signal.
5 Claims, 5 Drawing Figures PMENTEUAF 75 876, l 71 sziznlqgs FIGI.
KBELL /7 3 FIGZ. 77
AWN/76 ACKNOWLEDGE [BUTTONS /B.F? FILTER DETECTOR\ I J N 23 pd 4p Pd 1 LOGIC UNITJ l5 Q; 22
W x i J DETECTOR SELECTOR RELAY saw 2 or '3 mQE RAILWAY SIGNALLING SYSTEM The present invention relates to an improved railway signalling system of the kind in which train borne indicators provide an automatic warning of the signal aspect to the driver of the train. The indicators are controlled by devices located between the rails of the track.
According to the present invention there is provided a railway signalling system comprising a permanent magnet positioned on a railway track at a point preceding a multi-aspect signal, an electro-inductor and an-antenna means positioned adjacent said magnet, means for energizing said electro-inductor with a dc. supply and said antenna means with high frequency signal in dependence upon the current aspect of the signal, detector means carried by a railway vehicle fordetecting the fields produced by said magnet, electro-inductor and antenna means and to provide a warning to a driver of the train corresponding to the current aspect of said signal.
A preferred embodiment of the present invention will now be described with reference to the accompanying drawings in which:
FIG. 1 is a plan view of a length of railway track in which the track mounted transmitting portion of a signalling system is positioned between the rails.
FIG. 2 is a schematic diagram of the detection and cab signalling equipment carried by the train.
FIGS. 3 and 4 are circuit diagrams of two possible arrangements of the electro-inductor and a track coil mounted on the railway track.
FIG. 5 is a circuit diagram of an alternative embodiment for the track mounted antenna.
As shown in FIG. 1, a permanent magnet and an electro-inductor 11 are laid between the rails 12 of a railway track. This combination ofa permanent magnet and an electro-inductor forms the basis of a known railway automatic warning system. Colour light railway signals commonly have four aspects, namely one green, two yellow and one red. The green aspect alone is lit to indicate that the line ahead is clear, and in this situation the electro-inductor is not energized by a suitable d.c. source. Detecting equipment carried by a train detects the magnetic fields of both the permanent magnet and the electro-inductor and when the latter is energized and its field is detected, equipment carried by the train automatically registers that a signal with a green aspect is being approached and consequently no braking action is required by the driver.
When however the two cautionary aspects, single or double yellow or the red stop aspect is lit, the electromagnet is not energized. The detecting equipment carried by the train registers this fact and operates an appropriate warning indicator on the train and unless appropriate action is taken by the driver, operates the train brakes.
In addition in the arrangement according to the present invention a loop antenna 13 of suitable size and of one or more turns is laid between the rails 12 adjacent the magnet and electro-inductor. I
The electro-inductor 11 is fed from a rectified a.c. supply and the antenna 13 is fed from an appropriate transmitter as will be described below, and the two elements can be energized or not as required as will be described.
A train passing along the rails 12 of the track in the direction of the arrow A, carries detecting equipment for detecting the fields produced by each of the three elements 10, 11 and 13. The table below shows how each of the two elements 11 and 13 is energized in dependence' upon the aspect of the signal being approached by the train.
Signal Aspect Permanent Elcctro- Antenna magnet inductor Red energized Yellow energized Double Yellow energized energized Green energized v energized 5th aspect energized energized energized aspects indicate the safe maximum speed at which the train should be driven.
Depending upon which combination of energized/not energized states of the three elements exists, the detect-' ing equipment activates an appropriate warning in the drivers cab which in certain cases must be acknowledged by the driver.
For use with other signalling systems, the equipment could be used to give suitable indication such as numerical indication of speed permitted. I
For a green aspect, the train equipment detects first the permanent magnet 10 and then the energized-electro inductor 11, the antenna 13 being unenergized. For a double yellow aspect the train equipment detects first the permanent magnet-10, then the antenna 13 which' is energized with an HR, carrier, the electro inductor 11 being unenergized.
For yellow and red aspectsneither the electro tor 11 or the antenna 13 is energized.
A detector 14 carried by the train detects the presence of the permanent magnet 10 and actuates a logic unit 15 which operates a display, alarm and acknowl edgment unit. The detection of the presence of a permanent magnet sets the logic unit 15 into a state such that if neither an energized electro-inductor 11 nor an energized antenna 13 are detected within a certain time interval, an audible warning sounds on a horn 1 6. The driver may acknowledge the warning by pressing an acknowledgment button 17 which is illuminated by the unit 15, which will cause the horn 16 to cease; if the driver doesv not do this, the train brakes will be automatically applied.
If an energized electro-inductor 11 is also detected by the detector l4within the stated time interval, indicatingagreen signal aspect, a further signal is sent to the logic unit 15 which causes a bell 18 to ring briefly and the logic unit 15 is reset. No acknowledgment action by the driver is necessary.
If a receiving aerial 19 carried by the train detects a carrier signal from the energized track loop antenna 13 within the stated time interval, in place of a detection induc- 3 bythe detector 14 of an energized electro-inductor, this signal is fed to a selector relay 20 via a band-pass filter 2i, amplifier 22 ahd detector 23, causing relay contacts 24 to switch over and connect an acknowledgrnentbutton 25 to the logic unit lSQThe logic unit 5 causes'a'n audible warning to sound on the horn 16 and the driver must acknowledge this warning of a double yellow aspect by means of the press button 25 which is illuminated by unit 15, otherwise the brakes will be automatically applied. The relay 'is reset by a signalfrom the logic unit 15 when the detector 14 detects the presence of the next permanent magnet 10, causing the logic unit 15 to again be connected to the acknowledgment button 17.
' l 'or'a-train fitted to'receive the 5th aspect, the display unit is more complex than that shown in FIG. 2, and ineludes a facility for the acknowledgment and display of agreen aspect. The logic unit 15 would require enhancing also, so that a second time interval is available, if bothithe permanent magnet 10 and electro inductor 11 have been detected, within which the presence ofa carrier signalfr om the loop antenna 13 may be detected in order that the train equipment might differentiate betweenthe green and 5th aspect conditions.
.ElGSg and 4 show alternative feed circuits for the electro-inductor l1 and the antenna 13. In FIG. 3, the electro-inductor 11 is fed by a cable 26 directly from a rectifiedac. supply, a relay switch 27 being included in,-th e, cable 26 which is closed wherever the inductor ll is. to bev energized. Similarly the antenna 13 is fed with a signal from an oscillator 28, for example a signal of 68 KHz frequency, by way of a cable 29. A relay sw;i,tch ,30,,is includedin the cable 29.
1'll' -E,lG;'4,' anarrangement is shown in which a common cable 31 is employed in place of the two separate cables 26 and 29 shown in FIG. 3. In this arrangement, a capacitor 32 connected in parallel with the coil of the elecitro-indu'ctor -1l; ensures that the high frequency signa'l'from the oscillator 28 does not affect the electroinductor-r'similarly a capacitor 33 in series with the an ten'na' .13, prevents the dc. signal from --the electroinductor supply from passing through the antennar13.
FIGS illustrates an alternative arrangement in which a carrier signal gen'erator34 consisting of a power supplyirni-t '35 on oscillator 36 and a power amplifier 37 is' p os'iti oned closely adjacent to the antenna 13, being coupled to it via a matching transformer 38. In this way the use of'lon'g lengths of high quality feed cablebetween the carrier generator 34 and the antenna 13 is a'v'oidedfflhe a;c. supply to the carrier generator 34 passes along a feed cable 39 and is switched by'means of'a relay contact 40, whi'chcon'tact is arranged to be closedwh'en" the signal aspect 'is' double yellow, and when it isdesiredftoexhibitthe 5th aspect." v
Similarly relay contacts 27 in the supply leads 26 for the electro inductor l1 closeto "energize the electro l inductor 11 when the signal aspect is green and when it is desired to exhibit the 5th aspect.
Asian alternative to using a loop antenna 13 in the arrange ent s hown in FIG. 5, a ferrite rod antenna of known'eonstruction can be employed to transmitth'e carrier signal to the pick-up coil 19.
As a further alternative, a frame antenna, which may be of prin td circuit constructiom could be used. This frame antenna could, be incor'poratedinto' the structure of the housing forthe generatorunit 34.
The 5th aspect referred to in the Specification in which both the electro-inductor 11 and the antenna 13 are energized, is intended for use with very high speed trains in order to extend the signalling range. Very high speed trains clearly require a considerably longer distance in'which to brake from maximum speed'to rest than do trains whose maximum speed is considerably less. The 5th signal aspect is intended for use in such situations, to indicate to the driver of a very highspeed train that'it is safefor'the train to travel at its maximum speed since the track ahead is clear for at least the necessarymaximum braking distance.
lclaim:
1. A railway signalling system comprising:
a permanent magnet positioned on a railway track at a-point preceding a multi-aspect signal,
an electro-induc'tor and'an antenna'means positioned in sequence directly following said magnet in the intended direction of movement of a train along said track,
means for energising said electro-inductor with a die.
supply and said antenna means with a high frequency signal in dependence upon the present aspect of the signal, detector means carried by a railway vehicle for detecting the fields produced by said magnet, by said electro-inductor and by said antenna means to provide a warning to adriver of the train corresponding to the present aspect of saidsignal, said detector means including a first and second in- .ductive pick-upcoil, said first pickup coil being adapted to detect the static magnetic field produced by the permanent magnetand by said electro-inductor, and said second pick-up coil being adapted to detect the high frequency alternating V magnetic field produced by said antenna, I said first coil being connected by way of a logic unit to a first and second alarm means, first acknowledgement means for said second alarm means, saidsecond coil being connected to a relay coil whose contacts connect said logic unit to a second alternative acknowledgment means for said second alarm means, said logic unit in response to detection by said first pick-up coil of a signal from said permanent magnet along actuating said second alarm means to thereby require the train driver to operate said firstacknowledgment means to prevent automatic application of the train brakes, said logic unit in response to detection by said first pickup coil of a signal from said permanent magnet followed subsequently by detection by said second pick-up coil of a signal from said antenna means controlling said relay unit to operate and thereby controlsaid logic unit to actuate said second alarm means to thereby require the driver to operate the secondacknowledgment means to prevent automaticapplic ation of the train brakes and detection by said first pick-up coil of a signal from said per- I manent magnet followed subsequently by a signal from said electro-in'du'ctor controlling said logic unit-to actuate said first alarmmeans, which requires no acknowledgment action by the driver.
2". A signalling system as-claimed in claim wherein a single feed cable .is used to connect said electroinductoritosaid d.c. supp'ly' and'said antenna means to said high frequency signal source, and wherein a first filter is connected to said electro-inductor to block said said antenna means is in the form of a closed loop of one or more turns.
5. A signalling system as claimed in claim 1 wherein 5 said antenna means is in the form of a ferrite rod.
UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION PATENT NO. I 3,876, 171 DATED April 8, 1975 INVENTOR(S) Michael S. Birkin It is certified that error appears in the above-identified patent and that said Letters Patent are hereby corrected as shown below:
Foreign Applicatiofi Priority Data March 17, 1972 Great Britain. 12642/72 Sigrted and sealed this 10th day of June 1975.
(SEAL) Attest: v
C. MARSHALL DANN RUTH C. MASON Commissioner of Patents and Trademarks Attesting Officer

Claims (5)

1. A railway signalling system comprising: a permanent magnet positioned on a railway track at a point preceding a multi-aspect signal, an electro-inductor and an antenna means positioned in sequence directly following said magnet in the intended direction of movement of a train along said track, means for energising said electro-inductor with a d.c. supply and said antenna means with a high frequency signal in dependence upon the present aspect of the signal, detector means carried by a railway vehicle for detecting the fields produced by said magnet, by said electro-inductor and by said antenna means to provide a warning to a driver of the train corresponding to the present aspect of said signal, said detector means including a first and second inductive pick-up coil, said first pick-up coil being adapted to detect the static magnetic field produced by the permanent magnet and by said electro-inductor, and said second pick-up coil being adapted to detect the high frequency alternating magnetic field produced by said antenna, said first coil being connected by way of a logic unit to a first and second alarm means, first acknowledgement means for said second alarm means, said second coil being connected to a relay coil whose contacts connect said logic unit to a second alternative acknowledgment means for said second alarm means, said logic unit in response to detection by said first pick-up coil of a signal from said permanent magnet along actuating said second alarm means to thereby require the train driver to operate said first acknowledgment means to prevent automatic application of the train brakes, said logic unit in response to detection by said first pick-up coil of a signal from said permanent magnet followed subsequently by detection by said second pick-up coil of a signal from said antenna means controlling said relay unit to operate and thereby control said logic unit to actuate said second alarm means to thereby require the driver to operate the second acknowledgment means to prevent automatic application of the train brakes, and detection by said first pick-up coil of a signal from said permanent magnet followed subsequently by a signal from said electro-inductor controlling said logic unit to actuate said first alarm means which requires no acknowledgment action by the driver.
2. A signalling system as claimed in claim 1 wherein a single feed cable is used to connect said electro-inductor to said d.c. supply and said antenna means to said high frequency signal source, and wherein a first filter is connected to said electro-inductor to block said high frequency signal and a second filter is connected to said antenna to block said d.c. signal.
3. A signalling system as claimed in claim 1 wherein the high frequency signal source is positioned at the track side adjacent said antenna means.
4. A signalling system as claimed in claim 1 wherein said antenna means is in the form of a closed loop of one or more turns.
5. A signalling system as claimed in claim 1 wherein said antenna means is in the form of a ferrite rod.
US341664A 1973-03-15 1973-03-15 Railway signalling system Expired - Lifetime US3876171A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US341664A US3876171A (en) 1973-03-15 1973-03-15 Railway signalling system

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US341664A US3876171A (en) 1973-03-15 1973-03-15 Railway signalling system

Publications (1)

Publication Number Publication Date
US3876171A true US3876171A (en) 1975-04-08

Family

ID=23338528

Family Applications (1)

Application Number Title Priority Date Filing Date
US341664A Expired - Lifetime US3876171A (en) 1973-03-15 1973-03-15 Railway signalling system

Country Status (1)

Country Link
US (1) US3876171A (en)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4301899A (en) * 1980-04-21 1981-11-24 General Electric Company System for automatically controlling an electrically propelled traction vehicle traversing a gap in wayside source of power
GB2356277A (en) * 1999-11-13 2001-05-16 Intelligent Cab Systems Ltd Train protection
GB2369913A (en) * 2000-11-29 2002-06-12 Antony Bannister Train protection system
FR2834955A1 (en) * 2002-01-21 2003-07-25 Regie Autonome Transports SYSTEM FOR CONTROLLING THE TRAFFIC OF A PUBLIC TRANSPORT VEHICLE ON A GUIDANCE LANE

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1857186A (en) * 1927-10-17 1932-05-10 Nat Safety Appliance Co Train control system
US1886062A (en) * 1928-06-12 1932-11-01 Sprague Frank Julian Train control
US1917372A (en) * 1928-08-01 1933-07-11 Associated Electric Lab Inc Train stop and cab signal system
US1964819A (en) * 1926-12-27 1934-07-03 Regan Safety Devices Co Inc Train control system
US3272981A (en) * 1963-04-04 1966-09-13 Gen Signal Corp Intermittent inductive transmission system

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1964819A (en) * 1926-12-27 1934-07-03 Regan Safety Devices Co Inc Train control system
US1857186A (en) * 1927-10-17 1932-05-10 Nat Safety Appliance Co Train control system
US1886062A (en) * 1928-06-12 1932-11-01 Sprague Frank Julian Train control
US1917372A (en) * 1928-08-01 1933-07-11 Associated Electric Lab Inc Train stop and cab signal system
US3272981A (en) * 1963-04-04 1966-09-13 Gen Signal Corp Intermittent inductive transmission system

Cited By (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4301899A (en) * 1980-04-21 1981-11-24 General Electric Company System for automatically controlling an electrically propelled traction vehicle traversing a gap in wayside source of power
GB2356277A (en) * 1999-11-13 2001-05-16 Intelligent Cab Systems Ltd Train protection
GB2369913A (en) * 2000-11-29 2002-06-12 Antony Bannister Train protection system
FR2834955A1 (en) * 2002-01-21 2003-07-25 Regie Autonome Transports SYSTEM FOR CONTROLLING THE TRAFFIC OF A PUBLIC TRANSPORT VEHICLE ON A GUIDANCE LANE
WO2003066407A1 (en) * 2002-01-21 2003-08-14 Regie Autonome Des Transports Parisiens System for controlling public transport vehicle traffic on a guide track

Similar Documents

Publication Publication Date Title
US2762913A (en) Railway train proximity warning system
CA2073581A1 (en) Cab signalling system utilizing coded track circuit signals
US3544788A (en) Position indication and control system for rail vehicle
US3876171A (en) Railway signalling system
US1816628A (en) Train stopping and speed controlling mechanism
US5735491A (en) Method and apparatus for detecting an approaching train by detecting a brake system status signal
US3359416A (en) Continuous rail track circuits
US3045112A (en) Vehicle control system
US1803292A (en) Automatic signal for automobiles
US2554056A (en) Multiple frequency intermittent inductive cab signal and automatic train control system
US2059160A (en) Automatic cab signal system
DE69132716T2 (en) ELECTRONIC DEVICE FOR AVOIDING CRASHES BETWEEN VEHICLES
US3167282A (en) Railroad warning device
GB1352416A (en) Track communications for continuous rail
GB2356277A (en) Train protection
GB1452894A (en) Indication apparatus
US2816219A (en) Coded railway signaling system
GB2320601A (en) Safety system for railways
US2607000A (en) Multilane traffic warning circuit
JP3570965B2 (en) Signal beginning warning device
FR2262836A1 (en) Alerting system for vehicle driver approaching hazard - has radio signal emitter in hazard zone car operating car alarms
US3046393A (en) Apparatus for the control of highway crossing signals
US3638014A (en) Vehicle track block signal apparatus
US1301949A (en) Signal.
US397270A (en) Electric railway-signal