US1770364A - Train-dispatching system for railroads - Google Patents

Description

July 8, 1930. s. N. WIGHT TRAIN DISPATCHING SYSTEM FOR RAILROADS Filed Oct. 13, 1927 3 Sheets-Sheet l O o L July 8, 1930. s. N. WIGHT TRAIN DISPATCHING SYSTEM FOR RAILROADS 1927 3 Sheets-Sheet 2 Filed Oct. 13

TTORNEY July 8, 1930.

s. N. WIGHT TRAIN DISPATGHING SYSTEM FOR RAILROADS Filed Oct. 13, 1927 3 Sheets-Sheet 3 ATTONEY Patented July 8, 1930 hit? SEDGWICK N. WIGHT, OF ROCHESTER, NEW YORK, ASSIGNOR TO GENERAL RAILVV'AY SIGNAL COMPANY, OF ROCHESTER, NE'W YORK TRAIN-DISPATCHENG SYSTEM F013, IRATLROADS Application filed October 13, 1927. Serial No. 225,925.

This invention relates to train dispatching systems of the way side signal indicating type.

In accordance with the present invention it is proposed to so organize the circuits for controlling a distant switch machine and the sig nals associated therewith over a single line circuit, such as shown in my prior application Ser. No. 120,423, filed July 3, 1926, that a continuing visual and a momentary audible signal is given when a train enters the detector track circuit associated with the track switch operated by such switch machine, to give a momentary visual and audible signal when the switch machine is started and when it has completed its operating stroke in response to indicating current transmitted over the same line circuit as that used for controlling such switch machine and signals.

More specifically, it is proposed to carry the control circuit connecting the dispatchers oflice and the distant track switch through contacts which are open when the detector track circuit associated with such track switch is occupied, so that the continuity of the circuit may be ascertained at the dispatchers office, to sound an audible signal when the continuity of this line circuit is first broken at a point remote from the dispatchers office, and to momentarily break this line circuit at the beginning and again at the end of each operating cycle of the switch machine.

Other objects, purposes and characteristic features of the invention are in part obvious from the accompanying drawings and will in part be pointed out in the description thereof hereinafter.

In describing the invention in detail reference will be made to the accompanying drawings in which Fig. 1 shows the circuits at the distant way station as well as those located in the dis patchers oflice of one embodiment of the pres ent invention.

Fig. 2 shows a modified form of the invention in which the circuits have been simplified to the extent of eliminating one of the relays.

Fig. 3 shows another modification,further simplifying the circuit arrangement by the omission of another relay; and

Fig. 4 shows still another modification in which separate sources of current are used for the control and indication circuits.

Stmocttfre F 2 9. J.Referring to Fig. 10f

the drawings the dotted rectangle DO represents the dispatchers office, from which the switch machines and signals at both ends of a plurality of passing sidings of a railway system are controlled. In this dispatchers ofiice is located a control board, preferably having a miniature track layout associated therewith, of which one passing siding of the miniature track layout and two levers L and L for controlling the switch machine and signals at opposite ends of the corresponding siding only have been illustrated. At the ends of the siding of the miniature track layout shown, are provided indicating lamps 5 and 6, which are used for indicating the occupancy of the detector or fouling track circuits associated with the track switch at the ends of the corresponding passing siding of the railway system. There is associated with each lever a line relay LR, a bell relay BR and a secondary bell relay SBR; and there are also provided manually operable switches 7 or push buttons 7 and 8'for each lever. Only one audible signal or hell BL. has been illus trated, which is in practice connected in a,

circuit arrangement so that if any one of the bell relays BB is energized while its secondary bell relay SBR is de-energized this bell BL will sound. Any number of such audible signals may be used one for each group of levers, which levers may be divided in groups depending on local conditions and the number of bells desired to be used-in a particular 7 is only conventional and reference may be made to my prior application above referred to, if desired, for a more complete showing. The control relay Z is controlled from the dispatchers oflice D0 in a manner as more readily explained in the operation of the system. This control relay Z, through its neutral contact 12 and polar contact 13, is adapted to permit clearing of any one of the signals 1, 1 2 and 2 through circuits including the contacts closed in accordance with the position of the track switch, either through contacts operated by the switch machine or contacts in the usual switch boX associated with such track switch, and the conditions of energization of home relays, the energization of which home relays depends upon trathc conditions ahead of thesignal to be operated. In the particular arrangement shown the track switch 13 has associated therewith the usual detector track circuit including the track battery 15 and the track relay T, of which the latter is shown conventionally by a dotted line. In order to indicate at the dispatchers oh'ice whether the switch machine SM is assuming an extreme normal or reverse position or whether it is assuming some intermediate position a switch machine relay WVP has been provided, which relay, among other things, controls signaling or OS-ing relay OS. It is be lieved that the present invention can be most readily described by explaining the operation of the system illustrated in Fig. 1.

Operation Fig. 1.Under normal conditions, that is when all of the four signals 1, 1 2 and 2 are held at stop and when the lever L is in its neutral position the relays LR, BB and SEE in the tower are all doenergized, as shown, and the audible signal BL is silent and the indicatin lamp 6 is extinguished At the distant passing siding SD, of which the tracl: switch 155 and the signals associated therewith may be controlled by this lever L, the control relay Z is die-energized as shown, but the relays T and OS are in their normal energized condition. The home relays 2H and 1H have been shown in their normal energized condition on the assumption that traflic condi tions in the single track section 0 as well as on the main track of the passing siding SD are clear, that is, these track sections are not occupied.

In order to simplify the illustration of the system shown in Fig. 1, the positive side of a suitable source of current has been designated B, the negative side of this source of current has been designated N and the neutral point of this source has been designated C. This source of current preferably comprises a battery although a direct current generator of the Edison three wire type may be used, if desired. Further, alternating current may be used equally as well as direct current although in that event more line circuits are required because two independent circuits are necessary to operate a three position alternating current relay.

If the train dispatcher moves the lever L in a clockwise direction he energizes the control relay Z toward the right through the following circuit :beginning at the terminal contact 21, wires 22, 23 and 24-, contacts 25-26 wires 27, 28 and 29, winding of the relay LR, line wire 30, contact 31 of the relay OS, wire 32, winding of the control relay Z, to common wire C (not shown) connected to the midpoint of said battery. The completion of this circuit causes the relay LR and Z to assume their energized position, and it the dispatcher continues his movement of the lever L to its extreme position the circuitjust traced is broken at the contacts 2526 but is reestablished through wires 33,

and 35 and the stick contact 36 of the relay LR. It is thus seen that movement of the lever L toward its normal position completes a pick up circuit for the line relay LR and that the line relay LR is maintained energized through a stick circuit if the lever L is moved to the extreme normal position.

In this connection it should be noted that the relay BR and the indicating lamp 6 will not be momentarily energized while current is applied to the relay LR and the line circuit 30 while the contact 36 01"" this relay LP.-

is still in its lowermost position, because the circuit for the indicating lamp 6 and the relay BB is at that time open by reason of the contacts 3738 not having yet been closed, this because the relay LR is suili ciently quick acting to have assumed the energized position before the lever L has been moved to its extreme position.

Energization of the control relay Z to its right hand position will operate the switch machine SM to the normal straight track position, if it has not already assumed that position, and will permit clearing of the starting signal 2 through the following circuit beginning at the terminal B of a suitable battery, neutral contact 1:2, control relay Z. wire 40, polar contact 18, wire il, contacts l24:8 of the switch machine closed only when it assumes its normal position, wire 44, signal mechanisms (not shown) of the starting signal 2, wires and 46, front contacts l7 of the home relay 2H to the common return wire 0.

Let us now assume that a train moving from left to right on the main track of siding SD accepts the starting signal 2. and proceeds into the single track section 0. As soon as this train treads upon the detector track circuit associated with switch 1S, the track in. T is Clo-energized thereby dropping its front contact as and breaking the energizing circuit tor the relay OS, which in turn due to dropping of a contact 31 opens the line circuit for the relay Z heretofore traced. This opening of the line circuit, however, will not effect de-energizati-on of the control relay Z because the following supplemental circuit 1 will maintain the relay Z to the position to which it was just energized :--starting at the battery 50, wire 51, polar contact 52 of the control relay Z, wire 53, neutral contact 54 of the controlrelay Z, wire 55, contact 31 of the relay OS, wire 32, winding of the control relay 2 through a common wire O to back contact 56 of th relay OS, wire 57 to the neutral point of the battery 50. The opening of the line circuit at the contact 31 just mentioned, however, will effect de-energization of the line relay LP. located in the dispatchers ofiice DO, and dropping of this line relay LR will complete an energizing circuit for the bell relay BR as follows beginning. at the-terminal B contacts 20-21 of the lever L, Wires 23, 33 and 34:, contact 36 of the relay LR in its lower position, wires 58 and 59, winding of the relay BR, wires60 and 61, push button contact 7, wires 62 and 63, contacts 37-38, to common return wire O connected to the midpoint of said battery. vVith the relay BR energized the following circuit for the audible signal BL is complet ed :beginning at the terminalB, winding of the audible signal BL, wire 65, contact 66 of the relay SBR in the de-energized con dition, wire 67 front contact 68 of the relay BB, wires 69 and 61, contact 7, wires 62 and 63, contact '37-38, to the common return wire C. The circuit just completed causes the bell BL to sound, but this circuit is only momentarily completed, because as soon asit assumes its energized condition the circuit for the bell BL is broken at the contact 66 of the relay S33. If cesired the switch -7 may be left open, in which "event no audible signals will be given. The circuit for the secondary bell relay SBB may be traced as follows :-beginning at the terminal'B, contact 2021, wires 22, 23, 33, 70 and 71, contact 72 of the relay BR, wire 73, winding of the relay SBR, to the common return wire C. It is thus noted that upon entering of the train in question upon the detector track circuit causes the bell BL to be sounded momentarily. This entering of the train upon the detector track circuit and its breaking of the line circuit also causes the indicating lamp 6 to be energized, this through the following circuit remembering that the contact of the relay LR is in its de-energized condition so long as the track relay T is down beginning at the terminal B, contacts 20-21, wires 22, 23, 33 and 34, contact 36 in its lower position, wires 58 and '75, indicating lamp 6, wires 76 and 63, through, contacts 3738, to the common return wire C Al though the bell BL is only momentarily sounded the lamp 6 will remain lighted so long as the detector track circuit remains occupied. Also, although with switch 7 open no audible signal is given, the lamp 6 is nevertheless illuminated.

In the dispatching of train movements it is usually important to know only when a certain track section is being occupied rather than how long is occupied, and if the dispauc'hor has taken account of the illumination of the lamp 6 he may operate the lever L toward the neutral position to a point where contacts 3T-38 are opened. It the lever is moved to a position where contacts 20 and 25 are both bridged by their respective contacts 21 and 26 the relay LR will be rendered nonstick and this relay and the relay Z will be reenergized as soon as the detector track circuit is cleared, thus allowing a following.

train to proceed. This, by opening of contacts 37-38 also cancels the visual indication by extinguishing the lamp 6.

As soon as the train in question has moved entirely into the single track section O the detector track relay T is again energized,

,t iereby rte-energizing the relay OS and breaking the stick circuit for the control relay Z and reclosing the line circuit at the front Contact 31 of relay OS. Since the line relay LR, and also the relay Z connected in series therewith, were heretofore, with the lever L in its extreme right-hand position,

energized through a stick circuit including a the sticlrco itact 36 of relay LR the reclosing of contact 31 will not cause the line relay LE.- to pick up, nor will the line circuit 30 thereafter be energized, and the control relay Z will remain-in its de-energized normal 7 condition. In this connectionit is desired to point out that the train dispatcher may close the manually operable switch 8 momentarily and thereby again pick up the line relay LR which will cause. energization of the control relay Z and the clearing of signal 2 as soon as the train in question has advanced sulficiently far into the single track section O.

I This later procedure would be followed-in the event that it is desired to have a second train I follow the train in question into or out of the single track section O. It is thus seen that the arrangement automatically allows only the first of several following trains to pass the switch location for each act by the dispatcher of clearing a slgnal, thus making the signals in fact stick slgnals, if desired.

' It is believed unnecessary to specifically completed its operating stroke. During this time the relay OS will be energized from the negative terminal of the battery 80, or in other words the relay OS will have its polarity reversed at the beginning of the operation of switch machine SM, and will again have its polarity reversed when the switch machine SM has completed its operating stroke. This reversal of polarity of current applied to the relay OS will cause it to be momentarily de-energized when the switch machine is started and when it has completed its operating stroke. It is thus seenthat starting of the switch machine will deenergize the relay LR- connected in a stick, and will momentarily sound the bell BL and illuminate the indicating lamp 6 continuously until either the lever L is moved to its neutral position or the push button 8 is closed, and that if the push button 8 is closed during the operation of the switch machine SM, the relay LR will pick up, extinguishing the lamp 6, and then momentary audible and visual signal is given when the switch machine has completed. its operating stroke.

Attention is directed to the fact that movement of the lever L in a counterclockwise direction will not effect energization of the control relay Z in the event that the lever L is at that time in the left hand or counterclockwise position, because contacts 22 are connected to the negative terminal N of the battery through wire 81 and contacts 82 closed only when lever L assumes the neutral or clockwise position. This feature is merely an interlock between the levers associated with a passing siding, and has very little relation to the present invention, and is more particularly pointed out in another application (to-pending with the present application.

lli oclificcl construction (Fig. 2) .The of invention shown in Fig. 2 of the drawings is exactly the same as that shown in Fig. 1 as far as the waystation or trackway apparatus is concerned, and for this reason the tower equipment only has been shown in the drawing. Generally speaking this tower apparatus is exactly the same as that shown Fi 1 except that the relay BR i-een entirely omitted, the bell BL being ed and the secondary bell relay SEE bein directly controlled by the back contact 2361-72 of the line relay LR, which contact rries out the functions of the consystem shown in Fig. In other words, the directly energized by S TQ of the line relay LR. circuit for the audible signal BL is, short interval of delay, again broken in response to lifting of the contact 66 of the secondary bell relay SBR. Obviously, the manually operable switch 7 is omitted because this switch is a part of the hell relay BR and has been omitted with it. This modified form of the construction functioning in exactly the same way as that shown in Fig. 2 of the drawing, except that the audible signal cannot be cut out in the same manner as it is in the arrangement shown in Fig. 1, namely by the opening of the switch 7.

i zfodificd construction 3).The modified form of the invention shown in Fig. 3 of the drawings is exactly the same as that shown in Fig. 2, except that the secondary bell relay SBR is entirely omitted, and the bell BL is connected in series with the indicating lamp 6. This bell BL may be either of the vibratory type which sounds so long energized or may be a bell of thesingle stroke type which sounds only when current first applied thereto. if a bell of the vibratory type is used it will of course sound as long as the indicating lamp is illuminated, and if a single stroke bell is employed a single tap is sounded when the lamp 6 is illuminated after which the audible signal ceases. It is of course apparent that this bell BL may have two gongs associated therewith one of which is sounded upon the application of energy to its winding and the other of which is sounded when this energy is cut off.

Modified constmactz'on (Fig. .t).ln Fig. i of the drawings has been shown another embodiment of the present invention in which the line circuit 30 has been entirely isolated from the circuits for giving a visual and audible indication. It has been found expedient to use a higher voltage for the line circuit 30 than that commercially expedient for the control of the indicating lamp 6 and the bell BL. Indicating lamps of small candle power are usually designed and constructed to operate on a rather low voltage, such as 6 volts, this by reason of the diameter of filament required in a lamp of extremely low candle power and high volt- On the other hand, the line circuit 80, which may be from 10 to miles long, will increase the circuit resistance to such an extent that a much higher voltage than this is desirable for operating the control relay Z controlled through this line circuit. In View of these various facts. it is proposed in accordance with the invention as shown. in Fig. 4, to employ a high voltage battery, indicated by the terminals B, N and C, for the line circuit 30, and to employ the low voltage battery 90 for the visual and audible indicating circuits.

The circuit arrangement shown in Fig. 4, as far the line circuit and its control is concerned, is exactly the same as that shown in Fig. 2 of the drawings, and for this reason like parts and circuit portions have been designated by'like reference characters. The control and indication circuits are however slightly different, and are entirely insulated from the line circuit Instead of providing the line relay LR with'a single stick contact 36-72, there is also provided a contact 85,

which in its raised position energizes the secondary bell relay SBR, and when in its retracted position applies current to the bell BL and to the indicating lamp 6, this on the assumption that the secondary bell relay SBR has not yet assumed its deenergized position.

It should be noted that if the lever L is moved to either extreme position that the line relay LR is energized and after a short interval of time completes an energizing circuit for the secondary bell relay SBR which may be traced as follows beginning at the battery 90 having its one'terminal connected to the common return wire C, wire 84, front contact 85 of the line relay LR, wire 86, winding of the bell relay SBR, wire 87 connected to the common return wire 0. With the secondary bell relay SBR energized and its front contact 99 attracted the energizing circuit for the bell BL is partially completed at this contact 88, but no current can flow thereto because the contact 85 of line relay LR is still in its attracted condition thus opening the circuit for the bell BL at this contact 85. If now, the line relay LR is de-energized, possibly because the relayOS at the distant way station is de-energized, (see Fig. 1) the contact 85 of the line relay LR dropsand closes an energizing circuitfor the bell BL, as follows :beginning at the positive terminal of the battery 90, wire 84, contact 85 of the line relay LR when in its retracted position, wires 89 and 91, front contact 88 of the secondary bell relay SBR, wire 92, winding of the bell BL to the common return wire G connected to the other side of the battery 90. This energizing circuit will only remain closed for a very short period of time, because the dropping of contact 85 also deenergizes the secondary bell relay SBR and thereby opens the bell circuit at the contact 88. The indicating lamp 6 will, however, remain illuminated so long as the lever L is in one extreme position and the line relay LR is de-energized. This energizing circuit for the indicating lamp 6 may be traced as follows :starting at the battery 90, wire 84, back contact 85 of the line relay LR, wires 89 and 75, lamp 6, wire 76, through contacts 37-38, to the common return wire C connected to the other side of the battery 90. Attention is especially directed to the fact that the bell BL can only be sounded in response to de-energization ofthe line relay LR, this because the bell BL-can only be energized while the contact 88 of relay SBR is in its attracted position and the contact 85 of the line relay LR is in its detracted position, and this can only transpire immediately after de-energization of the line relay LR. This feature is very important in that it avoids the momentarily sounding of the audible signal BL due to movement of the lever L very quickly from its neutral to an extreme position. For instance, if, in the arrangement shown in Fig, 2 of the drawings, the lever L is moved very quickly from its neutral to an extreme position current may-momentarily flow to the bell BL while the contact, 36-72 is still in its retracted position. In the arrangement shown in Fig. 4 such momentarily ringing of the bell BL is impos sible even though the lever L is moved from an intermediate to an extreme position at the quickest possible rate.

Having thus shown several specific types of systems embodying the invention and having described the functions of the systems rather specifically, although the devices included in these systems have been shown con- 7 ventionally, it is desired to be understood that,

the systems shown have been selected for the purpose of exemplifying the invention rather than showing its scope or showing the exact circuit arrangements preferably employed in practicing the same and that various changes, modifications and additions may be made to adapt the invention to the particular railway signaling system to which the invention is to be applied, all without departing from the scope of the present inventionor the idea of means underlying the same, except as demanded by the scope of the following claims.

What I claim is: q 7

1. In a system of'remote' control'for traffic controlling apparatus for railroads, the combination with a single line circuit for coni trolling a distant traflic controlling device from a local tower, of a line relay connected in series in said circuit and located at said tower, a lever at said tower for applying electricalenergy to said line circuit, means for Opening said circuit at said distant trafic controlling device when a certain indication is to be transmitted, and means for continuously visually indicating and momentarily audibly indicating the opening of said line circuit at said distant traflic controlling 7 device.

2. In a system of remote control for traffic controlling apparatus for railroads, the combination with a single line circuit for controlling a distant traffic controlling device from a local tower, of a line relay connected in series in said circuit and located at said a tacts when said lever is moved to an extreme position.

3. In a system of remote control for traffic controlling apparatus for railroads, the combination with a single line circuit for controlling a distant traffic controlling device from a local tower, of a line relay connected in series in said circuit and located at said tower, a lever at said tower for applying electrical energy to said line circuit, means for opening said circuit at said distant traffic controlling device when a certain indication is to be transmitted, front contacts for said line relay, contacts for said lever for closing a pickup circuit for said line relay including said line circuit when said lever is moved partially toward an extreme position and for closing a stick circuit for said line relay including said line circuit and said front contacts when said lever is moved to an extreme position, and a manually operable switch for shunting said front contacts to render said relay non-stick.

a. In a train dispatching system; the combination with a distant track switch; a switch machine for operating said track switch; and of control and indicating means for controlling operation of said switch machine and for indicating the passage of a train over said track switch comprising: a single line circuit connecting a local oli ice and said distant track switch including a control relay located at said track switch and an indicating line relay located at said ofiice, a lever at said tower which if moved in one direction will first close a pick-up circuit for said line relay including said control relay, will then close a stick circuit for said line relay including said control relay and a front contact of said line relay, and will then close at one point an indicating circuit which may be closed at another point upon de-energization of said line relay.

5. In a train dispatching system; the combination with a distant track switch; a switch machine for operating said track switch; and of control and indicating means for controlling operation of said switch machine and for indicating the passage of a train over said track switch comprising: a single line circuit connecting a local olfice and said distant track switch including a control relay located at said track switch and an indicating line relay located at said olfice, a lever at said tower which if moved in one direction will first close a pick-up circuit for said line relay including said control relay, will then close a stick circuit for said line relay including said control relay and a front contact of said line relay and will then close at one point an indicating circuit which may be closed at another point by upon de-energization of said line relay, and manually operable means for shunting the front contact of said line relay.

6. In a train dispatching system; the combination with a distant track switch; a switch machine for operating said track switch; and of control and indicating means for controlling operation of said switch machine and for indicating the passage of a train over said track switch comprising: a single line circuit connecting a local office and said distant track switch including a control relay located at said track switch and an indicating line relay located at said office, a lever at said tower which if moved in one direction will first close a pick-up circuit for said line relay including said control relay, will tien close a stick circuit for said line relay including said control relay and a front contact of said line relay and will then close at one point an indicating circuit which may be closed at another point upon de-energization of said line relay, and a circuit in multiple with said indicating circuit including an audible signal.

7. In a train dispatching system; the combination with a distant track switch; a switch machine for operating said track switch; and in series, control and indicating means for controlling operation ofsaid switch machine and for indicating the passage of a train over said tIZLCi switch comprising: a single line circuit connecting a local office and said distant track switch including in series a control relay locatec. at said track switch and an indicating line relay located at said ofiice, means for opening said line circuit at said track switch upon the passing of a train over said track switch, a lever at said tower which if moved in one direction will first close said line circuit and will then close at one point in indicating circuit which is completed at another point upon de-energization of said line relay, whereby if said lever is moved in said direction said indicating circuit is not completed upon said movement of said lever unless said line circuit is open at another point as at said track switch.

8. In a train dispatching system; the combination with a distant track switch; a switch machine for operating said track switch; and of control and indicating means for controlling operation of said switch machine and for indicating the passage of a train over said track switch comprising: asingle line circuit connecting a local otlice and said distant track switch including in series a control relay located at said track switch and an inclicating line relay located at said office, means for opening said line circuit at said track switch upon the passing of a train over said track switch, an auXliary relay having an energizing circuit including a front contact of said indicating line relay, and an audible signal having an energizing circuit including a front contact of said auxiliary relay and a back contact of said indicating relay whereby said audible signal is only sounded momentarily upon deenergization of said indicating relay.

9. In a system of remote control for traffic controlling apparatus for railroads, the combination with a distant traffic controlling device; of a control relay at and controlling said distant device; a lever at a local ofiice; a line relay in said ofiice; a line circuit including contacts on said lever closed when said lever assumes a semi-extreme or an extreme position, said line relay and said control relay in series with a source of current; a track relay near said traiiic controlling device controlling contacts in said line circuit to cause de-energization of said line relay upon dropping of said track relay; indicating means at said office rendered active upon closure of an indicating circuit; said indicating circuit including back contacts of said line relay and contacts on said lever closed only when said lever assumes an extreme position; whereby since the line relay is energized before said lever completes said indicating circuit upon movement of said lever toward an extreme position a momentary false indication will not be given by said indicating means, but said indicating means will respond todropping of said track relay.

10. In a system of remote control for traffic controlling apparatus for railroads; the combination with a distant railway signal; of a normally closed track circuit including a track relay adjacent said signal; a control relay for clearing said signal; a line relay located at a local dispatchers oflice; a lever in said dispatchers ofice; contacts controlled by said lever to first complete a circuit including said control relay, the winding of said line relay, a line wire, contacts closed when said track relay is energized, and a source of current, and then close a circuit including said control relay, the Winding of said line relay, said line wire, contacts closed when said track relay is energized, said source of current and front contacts of said line relay upon movement of said lever from its normal position; indicating means rendered active whensaid line relay is de-energized; whereby movement of said lever first closes a pick-up circuit and then closes a stick circuit for said line relay and control relay, and said signal will not again clear after having been put to stop by a passing train unless the dispatcher again operates said lever.

11. In a system of remote control for traffic cont-rolling apparatus for railroads; the combination with a distant railway signal; of a normally closed track circuit including a track relay adjacent said signal; a control relay for clearing said signal; a line relay located at a local dispatchers otfice; a lever in said dispatchers oflice; contacts controlled by said lever to complete a circuit including said control relay, the Winding of said line relay, a line wire, contacts closed when said track relay is energized, and a source of cur- SEDGWICK WIGHT.

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