US1163720A - Railway signaling. - Google Patents

Railway signaling. Download PDF

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US1163720A
US1163720A US84672914A US1914846729A US1163720A US 1163720 A US1163720 A US 1163720A US 84672914 A US84672914 A US 84672914A US 1914846729 A US1914846729 A US 1914846729A US 1163720 A US1163720 A US 1163720A
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track
territory
relay
signal
train
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US84672914A
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Herbert A Wallace
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Hitachi Rail STS USA Inc
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Union Switch and Signal Inc
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61LGUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L23/00Control, warning, or like safety means along the route or between vehicles or vehicle trains
    • B61L23/08Control, warning, or like safety means along the route or between vehicles or vehicle trains for controlling traffic in one direction only
    • B61L23/14Control, warning, or like safety means along the route or between vehicles or vehicle trains for controlling traffic in one direction only automatically operated
    • B61L23/16Track circuits specially adapted for section blocking
    • B61L23/163Track circuits specially adapted for section blocking using direct current

Definitions

  • My invention relates to railway signaling, and particularly to signaling for two or more parallel tracks on bridges or other 10- calities where it is desirable, for purposes of safety, to limit the number of trains which may simultaneously occupy a given territory, such, for example, as the territory in the middle of a bridge span or a railway station.
  • Figure 1 is a diagrammatic view showing two parallel tracks over which traffic moves in 0pposite directions, and one form of signaling system embodying my invention for preventing more than one train from occupying a restricted territory.
  • Fig. 2 is a View showing two parallel tracks over which tratlic moves in the same direction, and one form of signaling system embodying my invention for preventing more than one train on either track from occupying a restricted territory.
  • W and E designate two parallel railway tracks over which traflic moves in opposite directions as indi catcd by the arrows.
  • AB is a restricted territory, that is, a territory in which only a limited number of trains are allowed at one time.
  • this territory may be the middle of a bridge span between two piers 10, 10.
  • only one train is permitted in the restricted territory at a time, that is, if a train'occupies track WV between A and B, then a train on track E must not enter this territory.
  • I provide signals and signal-controlling means such as I will now describe.
  • the rails of track VJ within the restricted territory are electrically separated from the adjacent portions by insulations 2 at points A and B, and form part of a track circuit which also includes a source of current 6, here shown as being a battery, and a track relay T. with a similar track circuit which includes the rails of the restricted territory, a battery b and a track relay T
  • a preliminary section eX- tending to the rear from the restricted territory, which sections are designated BD and AC respectively, and each of these preliminary sections is provided with a track circuit comprising the track rails, a
  • Track E is provided battery 6, and a track relay, which latter relays are designated T and T respectively.
  • the limitations of these preliminary track circuits are determined by insulations 2 at the points C and D.
  • each signal S and S I provide a signal relay, which relays are designated R and R respectively, and each of which relays is controlled by the track relay of the preliminary track circuit for the other track.
  • the circuit for signal relay R is from battery 3 through wires 4 and 5, contact 6 of relay T wires 7 and 29, relay R common wire 0 to battery 3.
  • relay R is closed only when preliminary section A-G is unoccupied.
  • Signal relay R is provided with a similar circuit which is controlled by contact 6 of track relay T of preliminary section B D.
  • Each of the signals S and S is con trolled by the corresponding signal relay K or R and also by both track relays T and T of the track circuits in the restricted territory.
  • the circuit for the control of signal S is from battery 3 through wires '1 and 14-, contact 15 of track relay T wire 16, contact 17 of track relay T, wire 18, contact 19 of relay R wire 20, signal S wire 21 and common wire 0 to battery 3.
  • the circuit for signal S is similar, being controlled by relays R T and T
  • the track relays for the preliminary sections may also, if desired, be employed to control other signals for their own tracks.
  • the circuit for each signal relay R and R is provided with means for removing the corresponding relay from the control of the track relay for the opposite preliminary section, and this means is controlled by the other signal relay.
  • the means for removing relay R from the control of track relay T is a shunt around contact 6 of the latter relay, which shunt comprises wire '8, back contact 9 of signal relay R and wire 10.
  • the circuit for signal relay R is provided with a shunt around contact 6 of track relay T, which shunt comprises wire 11, back contact 12 of relay R and wire 13.
  • Fig. 2 I have here shown two. parallel tracks E and E over which ways moves in the same direction, this direction being indicated by the arrow.
  • the space between points A and B is restricted territory in which only one train is to be allowed at a time, either on'one track or the other.
  • Each track is provided with a track circuit comprising the rails between A. and- B, the track relays for these track circuits being designated T and T.
  • T and T the track relays for these track circuits.
  • For each track I also provide a preliminary section C-A extending to the rear from the restricted territory, which preliminary sections are also provided with track circuits comprising track relays T and T respectively.
  • Traffic into the restricted territory on track E is governed by a signal S and traflic into the same territory on track E is governed by a signal S
  • Signal S is controlled by both relays T and T for territory AB, the circuit being from battery 3 through wires 22 and 23, contact 2% of relay T wire 25, contact 26 of relay T, wire 27, signal S wire 28 to battery.
  • a train in territory A"B on either track will hold signal S at stop Signal S is likewise controlled by both relays T and T for the restricted territory, and also by contact 30 of relay T for the preliminary section of track E;
  • signal S will be held at stop by a train in the restricted territory on either track and also by a train in the preliminary section on track E.
  • I have also shown two signals S and S for the preliminary sectionsof tracks E and E which signals are controlled in the usual manner by relays T and T for their respective tracks.
  • Theoper'ation of the system shown in Fig. 2 is as follows: A train on track E entering preliminary'section CA places signal S at stop'but hasno eftecton signals S and S Then'as this train enters restricted territory A -B'it places both signals S and S at stop and "holds them in that position until it leavesthe territory, so that no other train on either track is permitted to enter this territory until the first train leaves. A train on track E entering preliminary section CA places signal Stat stop and also signal S Then as the train enters the restricted territory AB it controls signals S and S in the same Way that these signals are con trolled by a train on the other track. Assume now that two trains simultaneously occupy the preliminary sections of the two tracks respectively. The train on track E would hold signal S at stop so that the other train could not enter the restricted territory, whereas signal S would remain at proceed so that the first train (the one on track E) would be permitted to enter the re stricted territory.
  • sufiicient apparatus for the control of the signals to accomplishthe desired purpose, namely, to prohibit the presence of more than one train in the restricted territory at one time. It is understood, however, that if desired the signals may in addition be con trolled by other means in accordance with the principles of any known forms of block signaling.
  • a railway having two or more tracks, a restricted territory thereon, signals for the several tracks for governing the passage of trains into said restricted territory, and means controlled by a train with in said territory on any track for causing all of said signals to indicate stop.
  • a railway having two or more tracks over which traflic moves in opposite directions, a restricted territory on said railway, signals fonthe several tracks for governing the passage of trains into said restricted territory, and means controlled by a train within said territory on any track for causing all of said signals to indicate stop.
  • a railway having two parallel tracks over which traffic moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a signal relay for each of said signals, a preliminary track circuit for each track extending to the rear from said territory and including a track relay, means for controlling each signal relay by the track relay of the preliminary track circuit for the other track, and manually controllable means for at least one of said signal relays for removing such signal relay from control by the track relay by which it is normally controlled.
  • a railway having two or more tracks, a restricted territory on said railway, signals for the several tracks for governing traitic into the restricted territory, means controlled by a train within said territory on any track for causing all of said signals to indicate stop, and means controlled by a train approaching said territory for causing the said signals for other tracks to indicate stop.
  • a railway having two or more tracks, a restricted territory on said railway, signals for the several tracks for governing tratlic into the restricted territory, and means controlled by a train on one of said tracks approaching said territory for causing the signals for the other tracks to indicate stop.
  • a railway having parallel tracks over which traflic moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into the restricted territory, and means controlled by a train on each track approaching said territory for causing the signals for the other tracks governing traflic into said territory to indicate stop.
  • a railway having two parallel tracks over which trafiio moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a signal relay for each of said signals, a preliminary track circuit for each track extending to the rear from said territory and including a track relay, and means for con trolling each signal relay by the track relay of the preliminary track circuit for the other track.
  • a railway having two parallel tracks over, which traffic moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a signal relay for each of said signals, a preliminary track circuit for each track extending to the rear from said territory and including a track relay, means for controlling each signal relay by the track relay of the preliminary track circuit for the other track, and means controlled by a signal relay when operated by a train on the other track for removing the other signal relay from control by the track relay by which it is normally controlled. 4
  • a track circuit for each track comprising the track rails in the restricted territory and a track relay, and a preliminary track circuit for each track extending to the rear from 5 said territory and including a track relay,
  • a railway having two parallel tracks thereon, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a preliminary track circuit forone track extending to the rear from said territory and including a track relay, and means for controlling the signal for the other track by the track relay of the said preliminary track circuit.
  • a railway having two parallel tracks thereon, a restricted territory on said railway, a signalfor each track'for governing the passage of trains into said territory, a preliminary track circuit for one track extending to the rear from said territory and lncludmg a track relay, track 011- cuits for the tracks including the rails inthe restricted territory and track relays and means for controlling each signal by the track relays for both of the track circuits of the restricted territory, and for controlling the signal for one track by the track relay of the preliminary track circuit for the other track.
  • a railway having parallel tracks, a restricted territory on said railway, signals for thetracks, and means governed by trains 011 said tracks for controlling said signals to limit the number of trains which may simultaneously occupy said territory.

Description

H. A. WALLACE.
RAILWAY SIGNALING.
APPLICATION man JUNE 23.1914.
1,163,720. Patented 1160. 14, 1915.
2 SHEETS-SHEET l.
INVENTOR H. A. WALLACE.
RAILWAY SIGNALING.
APPLICATION FILED JUNE 23.1914.
1,163,729, Patented Dec. 14, 1915.
2 SHEETS-SHEET 2.
Qf u 1 N'T I 2; Q Qlz 5L E L a WITNESSES N INVENTOR a c/ siam.
COLUMBIA PLANOGRAPH C0,, WASHINGTON, u. c.
HERBERT A. WALLACE, OF NEW YORK, N.
Y., ASSIGNOR TO THE UNION SWIICH &
SIGNAL COMPANY, OF SWISSVALE, PENNSYLVANIA, A CORFORATION OF PENN- SYLVANIA.
RAILWAY SIGNALING.
Specification of Letters Patent.
Patented Dec. 1%, 1915.
Application filed June 23, 1914. Serial No. 846,729.
To all whom it may concern:
Be it known that I, HERBERT A. WVALLAGE, a citizen of the United States, residing at New York, in the county of New York and State of New York, have invented certain new and useful Improvements in Railway Signaling, of which the following is a specification.
My invention relates to railway signaling, and particularly to signaling for two or more parallel tracks on bridges or other 10- calities where it is desirable, for purposes of safety, to limit the number of trains which may simultaneously occupy a given territory, such, for example, as the territory in the middle of a bridge span or a railway station.
I will describe several forms of signaling embodying my invention, and will then point out the novel features thereof in claims.
In the accompanying drawings, Figure 1 is a diagrammatic view showing two parallel tracks over which traffic moves in 0pposite directions, and one form of signaling system embodying my invention for preventing more than one train from occupying a restricted territory. Fig. 2 is a View showing two parallel tracks over which tratlic moves in the same direction, and one form of signaling system embodying my invention for preventing more than one train on either track from occupying a restricted territory.
Similar reference characters refer to similar parts in each of the views.
Referring first to Fig. 1, W and E designate two parallel railway tracks over which traflic moves in opposite directions as indi catcd by the arrows. AB is a restricted territory, that is, a territory in which only a limited number of trains are allowed at one time. For example, this territory may be the middle of a bridge span between two piers 10, 10. In the form of my invention shown herein, only one train is permitted in the restricted territory at a time, that is, if a train'occupies track WV between A and B, then a train on track E must not enter this territory. To thus limit the number of trains in the restricted territory, I provide signals and signal-controlling means such as I will now describe.
cated adjacent the entrance end of the territory, and trai'iic into the same territory on track E is similarly governed by a signal S also located adjacent the entrance end of the territory. The rails of track VJ within the restricted territory are electrically separated from the adjacent portions by insulations 2 at points A and B, and form part of a track circuit which also includes a source of current 6, here shown as being a battery, and a track relay T. with a similar track circuit which includes the rails of the restricted territory, a battery b and a track relay T Each track is also provided with a preliminary section eX- tending to the rear from the restricted territory, which sections are designated BD and AC respectively, and each of these preliminary sections is provided with a track circuit comprising the track rails, a
Track E is provided battery 6, and a track relay, which latter relays are designated T and T respectively. The limitations of these preliminary track circuits are determined by insulations 2 at the points C and D.
For each signal S and S I provide a signal relay, which relays are designated R and R respectively, and each of which relays is controlled by the track relay of the preliminary track circuit for the other track. For example, the circuit for signal relay R is from battery 3 through wires 4 and 5, contact 6 of relay T wires 7 and 29, relay R common wire 0 to battery 3. Hence, relay R is closed only when preliminary section A-G is unoccupied. Signal relay R is provided with a similar circuit which is controlled by contact 6 of track relay T of preliminary section B D.
Each of the signals S and S is con trolled by the corresponding signal relay K or R and also by both track relays T and T of the track circuits in the restricted territory. For example, the circuit for the control of signal S is from battery 3 through wires '1 and 14-, contact 15 of track relay T wire 16, contact 17 of track relay T, wire 18, contact 19 of relay R wire 20, signal S wire 21 and common wire 0 to battery 3. The circuit for signal S is similar, being controlled by relays R T and T The track relays for the preliminary sections may also, if desired, be employed to control other signals for their own tracks.
For a reason which will appear hereinafter, the circuit for each signal relay R and R is provided with means for removing the corresponding relay from the control of the track relay for the opposite preliminary section, and this means is controlled by the other signal relay. As here shown, the means for removing relay R from the control of track relay T is a shunt around contact 6 of the latter relay, which shunt comprises wire '8, back contact 9 of signal relay R and wire 10. Similarly, the circuit for signal relay R is provided with a shunt around contact 6 of track relay T, which shunt comprises wire 11, back contact 12 of relay R and wire 13.
The operation of the apparatus thus far described, is as follows: If an eastbound train on track E enters preliminary section C A, the'consequent opening oftrack relay T opens the circuit for signal relay R so that signal S changes to stop indication and thus prohibits the entrance of a westbound train into the restricted territory A-B. As the eastbound train enters the restricted territory AB, the consequent opening of track relay T opens the circuits for both signals, thus holding signal S at stop andplacing signal S at stop. This condition of the signals is maintained until the train leaves the restricted territory, when both signals return to proceed position unless one or the other of the prelimi nary sections is occupied.
If, while the eastbound train occupies preliminary section CA, a westbound train should enter preliminary section BD, the consequent opening of track relay T would not cause signal relay R to open because contact 6 of this track relay is shunted by contact 12' of relay R which is already open; hence, signal S would continue to indicate proceed, thus allowing the eastbound train to enter the restricted territory.
It is sometimes desirable that when two trains approach the restricted territory at substantially the same time, one of them should be given preference over the other as to entrance into the territory. To permit of such selection, I provide a shunt around contact 6 of each track relay T and T which shunts include respectively normally open, manually operable circuit controllers K and K. Assume now that it is desirable to give preference to westbound trains; circuit controller K would be closed by an operator, thereby removing signal relay R from the control of track relay T Then if an eastbound train should enter section CA, it
would not affect either signal and would be permitted to enter the restricted territory Aj-B unless a westbound train has in the which train is first to enter its preliminary section.
Referring now to Fig. 2, I have here shown two. parallel tracks E and E over which trafic moves in the same direction, this direction being indicated by the arrow. As inF i g. 1, the space between points A and B is restricted territory in which only one train is to be allowed at a time, either on'one track or the other. Each track is provided with a track circuit comprising the rails between A. and- B, the track relays for these track circuits being designated T and T. For each track I also provide a preliminary section C-A extending to the rear from the restricted territory, which preliminary sections are also provided with track circuits comprising track relays T and T respectively. Traffic into the restricted territory on track E is governed by a signal S and traflic into the same territory on track E is governed bya signal S Signal S is controlled by both relays T and T for territory AB, the circuit being from battery 3 through wires 22 and 23, contact 2% of relay T wire 25, contact 26 of relay T, wire 27, signal S wire 28 to battery. Hence, a train in territory A"B on either track will hold signal S at stop Signal S is likewise controlled by both relays T and T for the restricted territory, and also by contact 30 of relay T for the preliminary section of track E;
the circuit for this signal is apparent and need not be traced. Hence, signal S will be held at stop by a train in the restricted territory on either track and also by a train in the preliminary section on track E. I have also shown two signals S and S for the preliminary sectionsof tracks E and E which signals are controlled in the usual manner by relays T and T for their respective tracks.
Theoper'ation of the system shown in Fig. 2 is as follows: A train on track E entering preliminary'section CA places signal S at stop'but hasno eftecton signals S and S Then'as this train enters restricted territory A -B'it places both signals S and S at stop and "holds them in that position until it leavesthe territory, so that no other train on either track is permitted to enter this territory until the first train leaves. A train on track E entering preliminary section CA places signal Stat stop and also signal S Then as the train enters the restricted territory AB it controls signals S and S in the same Way that these signals are con trolled by a train on the other track. Assume now that two trains simultaneously occupy the preliminary sections of the two tracks respectively. The train on track E would hold signal S at stop so that the other train could not enter the restricted territory, whereas signal S would remain at proceed so that the first train (the one on track E) would be permitted to enter the re stricted territory.
In this application I have shown only sufiicient apparatus for the control of the signals to accomplishthe desired purpose, namely, to prohibit the presence of more than one train in the restricted territory at one time. It is understood, however, that if desired the signals may in addition be con trolled by other means in accordance with the principles of any known forms of block signaling.
Although I have herein shown and described only two forms of signaling system embodying my invention, it is understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.
Having thus described my invention, what I claim is:
1. In combination, a railway having two or more tracks, a restricted territory thereon, signals for the several tracks for governing the passage of trains into said restricted territory, and means controlled by a train with in said territory on any track for causing all of said signals to indicate stop.
2. In combination, a railway having two or more tracks over which traflic moves in opposite directions, a restricted territory on said railway, signals fonthe several tracks for governing the passage of trains into said restricted territory, and means controlled by a train within said territory on any track for causing all of said signals to indicate stop.
3. In combination, a railway having two parallel tracks over which traffic moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a signal relay for each of said signals, a preliminary track circuit for each track extending to the rear from said territory and including a track relay, means for controlling each signal relay by the track relay of the preliminary track circuit for the other track, and manually controllable means for at least one of said signal relays for removing such signal relay from control by the track relay by which it is normally controlled.
t. In combination, a railway having two or more tracks, a restricted territory on said railway, signals for the several tracks for governing traitic into the restricted territory, means controlled by a train within said territory on any track for causing all of said signals to indicate stop, and means controlled by a train approaching said territory for causing the said signals for other tracks to indicate stop.
5. In combination, a railway having two or more tracks, a restricted territory on said railway, signals for the several tracks for governing tratlic into the restricted territory, and means controlled by a train on one of said tracks approaching said territory for causing the signals for the other tracks to indicate stop.
6. In combination, a railway having paral lel tracks over which traiiic moves in opposite directions, a restricted territory on said railway, signals for said tracks, and means governed by trains on said tracks for controlling said signals to limit the number of trains which may simultaneously occupy said territory.
7. In combination, a railway having parallel tracks over which traflic moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into the restricted territory, and means controlled by a train on each track approaching said territory for causing the signals for the other tracks governing traflic into said territory to indicate stop.
8. In combination, a railway having two parallel tracks over which trafiio moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a signal relay for each of said signals, a preliminary track circuit for each track extending to the rear from said territory and including a track relay, and means for con trolling each signal relay by the track relay of the preliminary track circuit for the other track.
9. In combination, a railway having two parallel tracks over, which traffic moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a signal relay for each of said signals, a preliminary track circuit for each track extending to the rear from said territory and including a track relay, means for controlling each signal relay by the track relay of the preliminary track circuit for the other track, and means controlled by a signal relay when operated by a train on the other track for removing the other signal relay from control by the track relay by which it is normally controlled. 4
10. In combination, a railway having two parallel tracks over which tratfic moves in opposite directions, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a signal relay for each of said signals,
a track circuit for each track comprising the track rails in the restricted territory and a track relay, and a preliminary track circuit for each track extending to the rear from 5 said territory and including a track relay,
means for controlling each signal relay by the track relay of the preliminary track circuit for the other track, and means for controlling each signal by the track relay for each track circuit in the restricted territory.
11. In combination, a railway having two parallel tracks thereon, a restricted territory on said railway, a signal for each track for governing the passage of trains into said territory, a preliminary track circuit forone track extending to the rear from said territory and including a track relay, and means for controlling the signal for the other track by the track relay of the said preliminary track circuit.
12. In combination, a railway having two parallel tracks thereon, a restricted territory on said railway, a signalfor each track'for governing the passage of trains into said territory, a preliminary track circuit for one track extending to the rear from said territory and lncludmg a track relay, track 011- cuits for the tracks including the rails inthe restricted territory and track relays and means for controlling each signal by the track relays for both of the track circuits of the restricted territory, and for controlling the signal for one track by the track relay of the preliminary track circuit for the other track.
13. In combination, a railway having parallel tracks, a restricted territory on said railway, signals for thetracks, and means governed by trains 011 said tracks for controlling said signals to limit the number of trains which may simultaneously occupy said territory.
14. In combination, a railway having parallel tracks, a restricted territory on said railway, signals for the tracks, and means .5
Copies of this patent may be. obtained for five cents each, by addressing the Commissioner of Patents.
Washington, I). C. I
US84672914A 1914-06-23 1914-06-23 Railway signaling. Expired - Lifetime US1163720A (en)

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