US1889458A - Railway traffic controlling system - Google Patents

Railway traffic controlling system Download PDF

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US1889458A
US1889458A US552884A US55288431A US1889458A US 1889458 A US1889458 A US 1889458A US 552884 A US552884 A US 552884A US 55288431 A US55288431 A US 55288431A US 1889458 A US1889458 A US 1889458A
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relay
switch
signal
circuit
contact
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US552884A
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Sedgwick N Wight
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SPX Corp
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General Railway Signal Co
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B61RAILWAYS
    • B61LGUIDING RAILWAY TRAFFIC; ENSURING THE SAFETY OF RAILWAY TRAFFIC
    • B61L21/00Station blocking between signal boxes in one yard
    • B61L21/06Vehicle-on-line indication; Monitoring locking and release of the route

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  • This invention relates to detector an'dtime looking for switch machines of railway systems. D Y
  • the safety afforded by the locking of power operated track switches is based on the premise, that if the signals associated with a ar ticular switch have assumed the stop position for a predetermined time, usually slightly in excess of the time required for a train to come to a stop from its maximum sp'eed,it will be safe to operate the switch in that the train will either have come to a stop will be oc-" cupying the detector locking circuit or will have passed entirely over the switch points.
  • thermal relay As a time measuring device it is-convenient to use a thermal relay, but if such a thermal relay is used it is important that such relay shall have returned to its "normal cool condition before it is again called upon to carry out its time measuring function, and in accordance with the present invention the ther mal relay is proposed to be put into service upon placing a signal in the stop posit on,
  • FIG. 1 illustrates conventionally an em bodiment of the invention as applied to a smgle switch machine for operating a track switch, which has associated therewith signals for governing traffic in either direction,
  • Fig. 2 illustrates the signal control relay in its deenergized condition, illustratingthe manner in which the contact segmentmay be locked in its abnormal condition by the back contact of the signalcontrol relay.
  • FIG. 1 the track rails 1 of the railway system have been shown divided into insulating sections by insulating' joints 2.to facilitate track circuiting, of which only the detector track'circuit containing the detector 1931.
  • this detector track circuit signifying the passage of a train over the switch points of track switch S.
  • This track switch S may be operated by a suitable power o erated switch machine SM, which in turn is controlled by the switch machine control relay WVZ.
  • the movement of traiiic toward the switch points is governed by the main entering signal 8 and the take siding signal 8,
  • thermal relay TR which thermal relay TR is mechanically co-ordinated with the back contact 10 of the signal control relay SZ through the medium of a sector 26.
  • This thermal relay TR con- "trols and is controlled by the signal relay SZ 5 and in turn alsocontrol's the lock relay LR.
  • These relays SZ and lVZ are controlled from a central dispatchers oifice DO through the levers WL and SL, respectively, all in a manner more clearly pointed out in connection with the operation of the system.
  • the signal control lever SL is now in its right-hand position, signifying east boundtraific, and main tains the signal relay SZ in itsright hand energized position through the following cirsuit z beginning at the terminal (rli) of the central office battery, signal lever SL, wire i2, relay SZ, wire 18, thermal element l4: (this thermal element is one of the usual bimetallic type comprising two metals which have different temperature coefficients of expansion welded together so that the'uni'tary 1 i structure bends in accordance with change in temperature, this element 1 1 bending upwardly in response to heating of the same), wires 15 and 16 back to the midpoint C of the central office battery.
  • the signals 7 and 8 may be cleared ifthe switch S assumes the proper position, this through the medium of wires 43 end 44 in a manner readily understood from the drawing.
  • the track switch S cannot be operated'until a predetermined pe iod of time has elapsed after the signals 7, assume the stop position, and that afteroperation of the switch machine and its associated track switch S these, sig- 1181s,)? any one 01 them cannot be cleared until the thermal relay TR has returned to It should also be noted that the switch machine SM cannot be operated unless the detector track relay TB is energized, this by reason of the fact that the front contact 37 of thetraclr ""relay Tincluded inthe operating circuits of the switch machine SM. The switch machine mayor course be returned to its normal position by the closure of its normal operating circuit including the normal wire Nprovid- ""ing, of course, that conditions are otherwise proper.
  • a track switch of a railway system a switch machine for operating said switch, a plurality of signals associated with said switch for governing movement of traffic over said switch, and a relay having a contact which if its attracted position closes a circuit for clearing any one of said signals and when its control circuit is open and said contact assumes itsretracted position it closes a circuit for controlling saidswitch machine, whereby said switch machine cannot be operated unless all of said signals are at stop.
  • a track switch of a railway system a switch machine for operating said switch, a signal associated with said switch for governing movement of traflic over said switch, a relay having a contact which if in its attracted position closes a circuit for clearing said signal and when in its retracted position closes a circuit for controlling said switch machine, and timing means for delaying the movement of said contactto said retracted position, whereby said switch machine cannot be operated until after a lapse of time after said signal has been put to stop.
  • a trackswitch of a railway system a switchmachine foroperating said switch, a plurality of signals associated with said switch for governing movement of trafiic over said switch, a relay having a contact which if in its attracted position-closes a circuit for clearing any one of said signals and when in its retracted position closes a circuit for controlling said switch machine, and timing means for delaying the movement of said contact to said retracted position, whereby said switch machine cannot be operated until said signals have been at stop for a predetermined period of time.
  • control relay for controlling said signal to permit clearing of said signal only when said control relay is energized, a time element device rendered active to energize said lock relay a predetermined time after being energized, a circuit for said time element device including a back contact of said control relay,
  • a track switch a switch machine for operating said track switch, a signal for governing movement of traflic over said track switch, a signal relay which if energized permits clearing of said signal, a switch machine relay for controlling said switch machine, two levers, two line circuits, one lever for controlling the energization of said signal relay over one line circuit and the other lever for controlling the energization of said switch machine relay over the other line circuit, and a contact in th control circuit of said switch machine relay closed only it said signal control relay is deenergized.
  • a track switch a switch machine for operating said track switch, a signal for governing movement of trafiic over said track switch, a signal relay which it energized permits clearing of said signal, a
  • switch machine relay for controlling said switch machine, two levers, one for energizing said signal relay and the other for energizing said switch machine relay, and a contact in the control circuit of said switch machine relay closed only if said signal control relay is deenergized and has been deenergized for a predetermined period of time.
  • a track switch of a railway system a switch machine for operatin g said switch, a signal associated with said switch for governing movement of traflic over said switch, a thermal relay having a normal cool condition and an active heated condition, a circuit which must be closed to cilect operation of said switch and closed only it said thermal relay has been caused to assume its heated condition, and a circuit for said signal which can be closed only it said thermal relay assumes its normal cool condition.
  • a track switch a switch machine for operating said track switch, a signal for governing movement of trafiic over said track switch, a signal relay which if energized permits clearing of said signal, a switch machine relay for controlling said switch machine, two levers, two line circuits, one lever for controlling the energization of said signal relay over one line circuit and the other lever for controlling the energization of said switch machine relay over the other line circuit, and a contact in the control circuit of said switch machine relay closed only if said signal control relay is deenergized.
  • a track switch a switch machine for operating said track switch, a signal for governing movement of traflic over said track switch, a signal relay which if energized permits clearing of said signal, a switch machine relay for controlling said switch machine, two levers, one for energizing said signal relay and the other for energizing said switch machine relay, and a contact in the control circuit of said switch machine relay closed only if said signal control relay is deenergized and has been deenergized for a predetermined period of time.

Description

Nov. 29, 1932. 5, w|GHT RAILWAY TRAFFIG CONTROLLING SYSTEM Filed July 24, 1931 Patented Nov. 29, 1932 UNITED sures PATE T SEIDGXTICK N. WIGHT, OI ROCHESTER, NEW YORK, ASSIGNOR To GENERAL RAILWAY SIGNAL COMPANY, or ROCHESTER, NEW YORK RATILWAY TRAFFIC CONTROLLING sYsrnii/I Application fired my 24,
This invention relates to detector an'dtime looking for switch machines of railway systems. D Y
The safety afforded by the locking of power operated track switches is based on the premise, that if the signals associated with a ar ticular switch have assumed the stop position for a predetermined time, usually slightly in excess of the time required for a train to come to a stop from its maximum sp'eed,it will be safe to operate the switch in that the train will either have come to a stop will be oc-" cupying the detector locking circuit or will have passed entirely over the switch points.
As a time measuring device it is-convenient to use a thermal relay, but if such a thermal relay is used it is important that such relay shall have returned to its "normal cool condition before it is again called upon to carry out its time measuring function, and in accordance with the present invention the ther mal relay is proposed to be put into service upon placing a signal in the stop posit on,
and this signal or any other associated signal "cannot again be cleared until the thermalrelay has returned to its normalcold condition.
Other objects, purposes and characteristic features of the presentinventien'will in part be obvious from the accompanyin drawing and will in part be pointedout hereinafter.
In describing the invention in detail reference will be made to the accompanying drawing, in which Fig. 1 illustrates conventionally an em bodiment of the invention as applied to a smgle switch machine for operating a track switch, which has associated therewith signals for governing traffic in either direction,
over either of two routes establishable by such track switch; and i Fig. 2 illustrates the signal control relay in its deenergized condition, illustratingthe manner in which the contact segmentmay be locked in its abnormal condition by the back contact of the signalcontrol relay.
Referring to Fig, 1 the track rails 1 of the railway system have been shown divided into insulating sections by insulating' joints 2.to facilitate track circuiting, of which only the detector track'circuit containing the detector 1931. Serial no. 552,884; I
track relay T and the track battery 3 has been illustrated, this detector track circuit signifying the passage of a train over the switch points of track switch S. This track switch S may be operated by a suitable power o erated switch machine SM, which in turn is controlled by the switch machine control relay WVZ. The movement of traiiic toward the switch points is governed by the main entering signal 8 and the take siding signal 8,
signaling system, as conventionally shown by the home relays H and H Associated with the signal control relay SZ is a thermal relay TR which thermal relay TR is mechanically co-ordinated with the back contact 10 of the signal control relay SZ through the medium of a sector 26. This thermal relay TR con- "trols and is controlled by the signal relay SZ 5 and in turn alsocontrol's the lock relay LR. These relays SZ and lVZ are controlled from a central dispatchers oifice DO through the levers WL and SL, respectively, all in a manner more clearly pointed out in connection with the operation of the system.
- Operation As shown in the drawing the signal control lever SL is now in its right-hand position, signifying east boundtraific, and main tains the signal relay SZ in itsright hand energized position through the following cirsuit z beginning at the terminal (rli) of the central office battery, signal lever SL, wire i2, relay SZ, wire 18, thermal element l4: (this thermal element is one of the usual bimetallic type comprising two metals which have different temperature coefficients of expansion welded together so that the'uni'tary 1 i structure bends in accordance with change in temperature, this element 1 1 bending upwardly in response to heating of the same), wires 15 and 16 back to the midpoint C of the central office battery.
Attention is directed to the fact that the thermal element 14 is now assuming its normal cooled position in engagement with its back contact, and that this element will be bent upwardly in response to the heating by its coil 17 surrounding the element 1 1- With the circuit just traced complete and energized the polar contact 18 will assume its right hand position and the neutral contact 10 will assume its raised position, so that the following circuit for the signal 8 is closed :beginning at the terminal of a suitable way station battery, front contact 10 of the relay SZ, wire 20, polar contact 18 of the relay SZ, wire 21, front contact 24 of relay H switch machine contact 22 closed only when the switch machine assumes its main track position, wire 23, mechanism of the signal 8 to the other terminal of said battery.
It is of course understood that it would be hazardous to permit the operator at the central oflice D0 to move his signal 8 to the stop position and immediately thereafter operate the switch machine SM, this because an approaching train moving at high speed might arrive at the switch S before it had completed its stroke or might be caused to take the siding at high speed and be derailed. For this reason, it is proposed in accordance with the present invention to require the lapse of a predetermined period of time after the signal 8, or any one of the other signals, has been operated to the stop position before the switch points may be operated. I
Let us now assume that the operator wishes to move the switch machine SM to the take siding position. If he moves his switch ma chine lever L to the dotted position, si nifying the take siding position, no response will take place for the circuit for the relay NZ is open at the front contact 25 of the lock relay LR. Let us, however, assume that the operator leaves his switch machine control lever L in the dotted position and then operates his signal lever SL to the intermediate stop position. This movement of the lever SL to the neutral stop position effects deenergization of the relay SZ and in turn ef fects opening of the energizing circuit for the semaphore signal 8, this by dropping of the contact 10 of the relay SZ. With this contact 10 of the relay SZ released it will engage the upper segment 26 of the angle lever or sector 26, thereby closing the following circuit for the coil 17 of the thermal relay TR:beginning at the terminal of the way station battery, back contact 10 of the relay SZ, sector 26 of the angle lever 26, wire 27, coil 17 of the thermal relay TR to the other terminal of the way station battery.
The closure of this circuit will of course heat the coil 17 and after the lapse of a predetermined time, say one to four minutes, the sector 26 will have been rotated in a right hand direction until the contact 10 drops from the segment 26 upon the segment 20 these segments being insulated from each other by insulation 26 This new position of contact 10 is shown in Fig. 2 of the drawing. Under this condition of the contact 10 the following circuit for the lock relay LR is completed :beginning at the terminal contact 10 of the relay SZ, sector 26 wire 28, winding of the lock relay L to the other terminal of the way station battery.
The completion of this circuit will close the contact 25 of relay LR, and since the lever WL assumes its dotted position the switch machine relay N Z will be energized through the following circuit :beginning at the ter minal of the central ofiice battery, lever WL in the dotted position, line wire 30, front contact 25 of the relay LR, wire 31, winding of the relay VIZ, wires and 16, back to the midpoint of the central office battery.
The completion of this circuit will of course operate the polar contact 35 of the relay Z to its left hand position and will effect closure of the neutral contact 36 of this relay lVZ, so that the switch machine SM may be operated to its take siding position through the following circuit :beginning at the terminal of the way station battery, front contact 37 of the track relay T, wire 38, neutral contact 36 of the relay lVZ, polar contact 35 of the relay NZ assuming its dotted position, reverse wire B through the motor of the switch machine to the other terminal of the way station battery. The completion of this circuit will of course operate the switch machine SM to its take-sid ing position upon the consummation of which the circuit will be broken by suitable means within the switch machine (not shown).
Let us now assume that the operator wishes to clear the starting signal 7", that is, wishes to set up west bound traiiic off of the side track of the passing siding PS. To accomplish this he will move his signal lever SL to its left hand dotted position, but the signal relay SZ cannot be energized until the thermal relay TR has again cooled sullicicntly to cause the thermal blade 14 to engage its cooperating back contact, after which the signal relay SZ will be energized to its left hand dotted position and complete the following circuit for the signal 7 :-beginning at the terminal (-1-), front contact 10 of the relay SZ, wire 20, polar contact 18 assrming its left-hand position, wire 40, front contact 39 of the relay H the switch machine contact 41 assuming its take-siding position, wire 4-2,
iii)
its normal cooledposit-ion.
"bound train oil? of the side track of passing siding PS.
Similarly, the signals 7 and 8 may be cleared ifthe switch S assumes the proper position, this through the medium of wires 43 end 44 in a manner readily understood from the drawing.
It is thus noted that the track switch S cannot be operated'until a predetermined pe iod of time has elapsed after the signals 7, assume the stop position, and that afteroperation of the switch machine and its associated track switch S these, sig- 1181s,)? any one 01 them cannot be cleared until the thermal relay TR has returned to It should also be noted that the switch machine SM cannot be operated unless the detector track relay TB is energized, this by reason of the fact that the front contact 37 of thetraclr ""relay Tincluded inthe operating circuits of the switch machine SM. The switch machine mayor course be returned to its normal position by the closure of its normal operating circuit including the normal wire Nprovid- ""ing, of course, that conditions are otherwise proper.
Applicant has thusshown-and described one rather specific embodiment of the present invention, but it is desired to be understood that the particular embodiment se lected has iot been selected for the purpose of showing the scope of the invention or the exact construction preferably employed in practicing the invention, but has been -selccted for the purpose' of facilitating a description of the underlying principles of the invention, and the manner in which these principlesmay be employed in practicing V the same; and it is further desired'to be 1111 derstood that certain modifications and additions may be made to the invention as illustrated to adapt it to the particular problems encountered in practicing the same, all
without departing from the spirit or scope of the invention or the idea of means underlying the same, except as demanded by the scope of the following claims.
What I claim as new is I 1. In combination, a track switch of a rail way system, a switch machine for operating said switch, a signal associated with said switch for governing movement of traffic over said switch, and a relay having a contact which if in its attracted position closes a circuit for clearing said signal and when its control circuit is open and said contact assumes its retracted position it closes a circuit for controlling said switch machine, whereby said switch machine cannot be operated unless said signal is at stop.
2. In combination, a track switch of a railway system, a switch machine for operating said switch, a plurality of signals associated with said switch for governing movement of traffic over said switch, and a relay having a contact which if its attracted position closes a circuit for clearing any one of said signals and when its control circuit is open and said contact assumes itsretracted position it closes a circuit for controlling saidswitch machine, whereby said switch machine cannot be operated unless all of said signals are at stop.
' 3. In combination,a track switch of a railway system, a switch machine for operating said switch, a signal associated with said switch for governing movement of traflic over said switch, a relay having a contact which if in its attracted position closes a circuit for clearing said signal and when in its retracted position closes a circuit for controlling said switch machine, and timing means for delaying the movement of said contactto said retracted position, whereby said switch machine cannot be operated until after a lapse of time after said signal has been put to stop.
'4. In combination, a trackswitch of a railway system, a switchmachine foroperating said switch, a plurality of signals associated with said switch for governing movement of trafiic over said switch, a relay having a contact which if in its attracted position-closes a circuit for clearing any one of said signals and when in its retracted position closes a circuit for controlling said switch machine, and timing means for delaying the movement of said contact to said retracted position, whereby said switch machine cannot be operated until said signals have been at stop for a predetermined period of time.
5. The combination with a track switch of a railway system, of a switch'machine for operating said switch, a signal associated with said switch for governing movement of traflic over said switch, a lock relay which if deen- 'ergized prevents operation of said switch, a
control relay for controlling said signal to permit clearing of said signal only when said control relay is energized, a time element device rendered active to energize said lock relay a predetermined time after being energized, a circuit for said time element device including a back contact of said control relay,
7 element device for normally preventing a back' contact of said control relay from assuming its retracted position but which upon being energized for a predetermined period of time will allow it to assume such retracted position and energized only upon deenergization of said control relay, and a circuit for said lock relay including said back contact of said control relay. 7. The combination with a track switch of a railway system, of a switch machine for operating said switch, a signal associated with said switch for governing movement of traii'ic over said switch, a lock relay which it deenergized prevents operation of said switch, acontrol relay for controlling said signal to permit clearing of said signal only when said control relay is energized, a time element device for normally preventing a back contact of said control relay "from assuming its retracted position but which upon being energized for a predetermined period of time will allow it to assume such retracted position and energized only upon deenergization of said control relay, a circuit for said locl: relay including said back contact of said control relay, and means for deenergizi said time element device such predeterai ned period of time after being energized.
8. The combination with a track sw tch of a railway system, of a switch machine for operating saic switch, a signal associated ith said switch for governing movement of traflic over said switch, a lock relay which if deenergized prevents operation or" said switch, control for controlling signal to permit clearing of said signal only when said control relay is energized, latch for preventing a contact of said control relay assuming its retracted posi ion, a time element device for operating said latch to its active n O11-lltl1lllg position, a circuit for said time element device closed when said control relay is deenergized and said latch assumes its latching position, and a circuit for said lock relay closed only when the contact of said control relay assumes its retracted position.
9. In combination, a track switch, a switch machine for operating said track switch, a signal for governing movement of traflic over said track switch, a signal relay which if energized permits clearing of said signal, a switch machine relay for controlling said switch machine, two levers, two line circuits, one lever for controlling the energization of said signal relay over one line circuit and the other lever for controlling the energization of said switch machine relay over the other line circuit, and a contact in th control circuit of said switch machine relay closed only it said signal control relay is deenergized.
10. In combination, a track switch, a switch machine for operating said track switch, a signal for governing movement of trafiic over said track switch, a signal relay which it energized permits clearing of said signal, a
switch machine relay for controlling said switch machine, two levers, one for energizing said signal relay and the other for energizing said switch machine relay, and a contact in the control circuit of said switch machine relay closed only if said signal control relay is deenergized and has been deenergized for a predetermined period of time.
11. The combination with a track switch of a railway system, of a switch machine for operating said switch, a signal associated with said switch for governing movement of traffic over said switch, a lock relay which if deenergized prevents operation of said switch, a control relay for controlling said signal to permit clearing of said signal only when said control relay is energized, a circuit for said lock relay closed only it said signal control relay is deenergized and a thermal relay assumes its active heated condition, and a circuit t r said signal control relay closed only when said thermal relay assumes its normal inactive condition, whereby it is assured that said thermal relay has been sufficiently cooled before it is again called upon to function.
12. In combination, a track switch of a railway system, a switch machine for operatin g said switch, a signal associated with said switch for governing movement of traflic over said switch, a thermal relay having a normal cool condition and an active heated condition, a circuit which must be closed to cilect operation of said switch and closed only it said thermal relay has been caused to assume its heated condition, and a circuit for said signal which can be closed only it said thermal relay assumes its normal cool condition.
In testimony whereof I affix my signature.
SEDGVIICK N. WIGHT.
DISCLAIMER 1,889,458.Sedgwiclc N. Wight, Rochester, N. Y. RAILWAY TRAFFIC CONTROLLING SYSTEM. Patent dated November 29, 1932. Disclaimer filed February 23, 1934, by the assignee, General Railway Signal Company.
Hereby enters this disclaimer to claims 9 and 10 of said Letters Patent, which are in the following Words, to wit:
9. In combination, a track switch, a switch machine for operating said track switch, a signal for governing movement of trafiic over said track switch, a signal relay which if energized permits clearing of said signal, a switch machine relay for controlling said switch machine, two levers, two line circuits, one lever for controlling the energization of said signal relay over one line circuit and the other lever for controlling the energization of said switch machine relay over the other line circuit, and a contact in the control circuit of said switch machine relay closed only if said signal control relay is deenergized.
10. In combination, a track switch, a switch machine for operating said track switch, a signal for governing movement of traflic over said track switch, a signal relay which if energized permits clearing of said signal, a switch machine relay for controlling said switch machine, two levers, one for energizing said signal relay and the other for energizing said switch machine relay, and a contact in the control circuit of said switch machine relay closed only if said signal control relay is deenergized and has been deenergized for a predetermined period of time.
[Ofiicial Gazette March 27, 1.934.]
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