US2330532A

US2330532A - Centralized traffic controlling system for railroads

Info

Publication number: US2330532A
Application number: US417134A
Authority: US
Inventors: Sedgwick N Wight
Original assignee: General Railway Signal Co
Current assignee: SPX Corp
Priority date: 1941-10-30
Filing date: 1941-10-30
Publication date: 1943-09-28
Anticipated expiration: 1960-09-28

Description

2 Sheets-Sheet 1 S. N. WIGHT Filed Oct. 30,- 1941 CENTRALIZED TRAFFIC CONTROLLING SYSTEM FOR RAILROADS Sept. 28, 1943.

2 She ts-Sheet 2 ATl'OR NEY S. N. WIGHT Filed 001;. 30, 1841 CENTRALIZED TRAFFIC CONTROLLING SYSTEM FOR 'RAILRADS Sept. 28, 1943.

1 ,5 w 5 KO Patented Sept. 28, 1943 CENTRALIZED TRAFFIC/CONTROLLING. srsTEM on RAILROADS Sedg'wickN. Wighultochester, N. Y., assignor to General Railway Signal Company, Rochester,

1 Application em ers, 1941, saw No. 417,134

19 Claims. (01. 2463) The present invention relates to the remote control of signals on a railway' system and'to means for indicating when trains pass such signals, and more particularly to means for giving such indications without the employment of the usual detector track circuit.

It is very common practice to have a track circuit known in signal parlance as a detector track circuit for indicating when a train passes over the points of a track switch and passes by the. signals associated therewith. On many of the railway systems provided with signals which are controlled in accordance'with trafiic conditions no such detector track circuits arepr'esent and one of the principle features of the present invention resides in the provision of "circuits and apparatus for manifesting themovement of a train over the switch points of a track switch without the employment of either the usual de tector track circuit or the employment of a track instrument. More specifically, it is proposed to manifest such passage of a train over the switch points and to transmit an indication of such movement of the train by the signal to a distant control oifice by taking into consideration'the position the track switchis assuming at the time, the fact whether or not a particular signal is clear, and the fact whether 'the main track, the passing siding or the first portion of'a'single track section adjacent such passing siding is then occupied or unoccupied. Inother words, it isproposed to take a largehumber of facts into consideration and to determine from these facts whether or not there is a train-moving over the switch points and by'such construction avoid the necessity of providing additional insulating joints in the track rails and the additional track battery and track relay which would be necesa sary if the movement of the train over the switch points were to be ascertained by the employment of a detector track circuit. Another feature of the present invention resides in'theprovision of means for continuing theindication of a train movement over the switch points, ordiin the provision of novelsigna'ls which are 'no'r-' mally dark and which if illuminated instruct the traincrewto operate the'track switch'to the'fside track position and which assume a more favor- Other objects, purposes and characteristic features of the present invention will be pointed out in the specification hereinafter and will in part be understood when this specification is read in connection with the attached drawings, of which:

Fig. 1 shows one form of the present invention; and

inventionf I V Structure Fig. 1

Referring to Fig. l of the. drawings the apparatus illustratedin the lower left-hand corner comprises the apparatus locatedin the central officeCO; whereas the apparatus illustratedin the upper right-handcorner is ,located in the fieldFS, these-apparatuses being. connected by line wires it, H and i8, and common return wire C. ,In the actual tracklayout including a passingsiding PS the track rails. have been shown divided r into sections by insulating joints ii! p: which the;v section of the side track has been designated- 5. and the sections of; the main track from left tcfright havebeen designated 3, 4,1'

and 2, of which the sections I and constitute the main siding section of the passing siding and theisections z and 3 each constitute a section of a single track stretch. Additional insulating joints diandjumpers l 2.are employed to extend the track circuit of the main'siding section over the foulingportions of the side track. The left-v hand end of the passing siding isprovided with a track switch S103, and the. right-handend is provided with a track switch 5205., These, track switches may be power operated and controlled from the office, if desired, but in the disclosure illustrated these track switches are presumably operated by hand by a suitable means, not shown, and inaccordance with instructions transmitted able aspect in response to operation ofsaid track switch to such side track position.

through the medium of the wayside signals governing trafficonto and oh of the main siding sectionand side track. Each of the sections of main track are track circuited by apparatusv including a track batteryB and.a track relay lf',.;which track batteries and track relays are provided with reference; characters having a prefix ,corre:

spending to -.the number of the track section in which theyare located. yThat is, track section; ,3 is provided with a trackbattery (not shown) and a track relay 3T, track section 3 is provided with a track battery 43 and a track relay 4T, track section I is provided with a track battery IB and a track relay 1T, and track section 2,,is

provided with a battery (not illustrated) and a track relay 2T.

Fig. 2 shows a modified form of the present Four signals are provided for each track switch to govern the movement of traffic thereover. For the track switch Swl the east-bound signals have been designated S2 and 82A for governing traffic off of the main siding section and side track respectively and into the single track section. The signals for governing the movement of traflic over the tra'ckswitch Szul in a westwardly direction and .into the passing siding PS have been designated SI for the main siding section and SIA for the side track. Similarly, the signals for governing east-bound trafiic over thetrackswitch Sw3 have been designated S4 and "S4'Aan'd the signals for governing west-bound traffic over this track switch S203 have been designated S3 .and i S3A. These signals may be-dfany suitable construction such as semaphore signals, multiple unit light signals, or multiple'aspect light signals of the search-light type, having a movable spectacle color screen, but for convenience semaphore I signals only .have been. illustrated .for the main siding l section and search -light type signals only have been illustrated for the side track. The signals S l, S2, .SZ'A, S3, 83A and 54 .are preferably threesposition signals indicating green, yellow and red signifying clear, caution and danger, respectively, but for convenience their control circuits have only been shown conventionally to illustrate :under what conditions a signal is held at danger or stop and under what conditions it may indicate .proceed. Signals SiA and SEA are preferably two-position three-condition signals which normally assume the stop position "dark'condition and which may be operated to the illuminated condition manually from the-'central-cfiice. and which are operated to-the proceed position by operation of their associated track'switch'to the'side track position. Since the apparatus at each end of the passing siding'is identical the apparatus at the east end of "the passing siding-only'hasbeen shown in considerable detail, theappara-tus-at the west endhaving to a largeextent'beenomitted and the control and indication line wires for the west 'end *have. for convenience, been illustrated by a dotted line 15.

The track switch S10! is provided with point detector contacts 'CSiol and CSwZ, which contacts assume one or the other extreme position when the trac'kswitchassumes thecorresponding extreme normal or reverse position and is'l'ocked, or if desired these contacts CSw'! and'CSzD? "may be the 'usual switch box contacts which merely manifests the'position of the switch. These confacts have been illustrated 'in their normal main trackjposition. The'signalsSl, S'IA,'S2 andSZA are controlled by "the switch instruction relay SIR! and the signal direction relay DR'GI and also'in accordancewith the position assumed by the track switch Swl as reflected by'the switch box contacts 'CSw'l'. and also, except "for signal SIA. are controlled'in accordance with traffic conditions in advance. Some of the control contacts for governing these si nals in accordance with traific conditions inadvanceha've for convem'ence been omitted. The switch instruction reIaySIRI is controlled overthe line wire [6 and the common return wire "C, whereas the signal direction and control 'relay DRGI is controlled over line wire "I"? and the same common return wireC.

Referring now -to the apparatus in the ofiice, the track layout in the new has been shown in miniaturein'the .oflic'eby the conventional showing of a passing siding ps. At the east "end of this miniature passing siding ps has been illustrated a track occupancy indicating lamp 08!, a similar lamp 083 having been illustrated at the left-hand end of this miniature passing siding ps. These OS lamps CS1 and 053, which have been provided to manifest track occupancy at the switch points, are respectively lighted whena trainmoves over 'the pointsof the track switches 'Swi and Sw3,-and-are controlled by the indication relays OSRI and OSRE, respectively.

The switch instruction relay SIR! is controlled by the switch instruction lever SILI, the switch iinstructionlever SIL3 controlling a similar switch instruction relay not illustrated. The signal lever 'SGL3 controls a relay (not shown) similar to signal relay DRGI. As conventionally shown the OS indicating relays OSRI and OSR3 are double winding relays of which the upper winding of relay OSRI is controlled from the field over the line wire 3 and the lower winding comprises a portion of a stick circuit including the stick contactBB is controlled by .the signal lever controlled contact 35 The purpose of these indication relays OSRI and OSR3 will bemore specifically pointed out in connection with the operation of the system.

Operation Fig. 1

Under normal tramc conditionsthatis when there are no trains around and none expected to reach that portionof the railway system, .all of "the signals will-be heldat stop manually from the controlofilce C0, the signals SIAand 54A being dark signals their lamps being held deenergized manually and the track switches will assume their normal main track position, as illustrated. :Under this -condition all of the circuits will be deenergized and open except the circuit for the switch instruction relay SIR! which will be energized bycurrent of positive polarityand .thevarious track circuits which will be ener-gizedandunshunted and their track relays will assume'the energized attracted position.

Letus-now'assume thatthere is a west-bound train'm'oving from right to left somewhere beyond the section 2 in the single track-stretch extending eastwardly -from the passing siding PS. Let us further assume that the operator in the central ofiice CO-desires to clear'the signal S! at the field station ES to allow the train under consideration to move into the main siding section of the I'passing'siding-PS. Inorder to clear the signal Si, assuming clear traific conditions ahead, for governingwest-bound traffic over the main siding sections -l and 4 the operator will leave the switch instruction lever SILI in its right-hand position tom'aintain closed the energizing circuit passing from the terminal of the battery BB through the contact of this lever SILI, through line wire "l6, through the winding of 'the switch instruction relaySIRl, back through the common return wire C to the mid-point of the battery BB. Also to allow only a west-bound train tolmove over the track switch Swl the operator will move the direction signal lever DGL! to its left-hand position to close an energizing circuit for the direction signal relay DRGI which may be traced from the terminal minus of the battery BB through the contact of lever DGLI through line wire 17, through the winding of signal relayDRGl, and back'over the common return wire C. The closure of these circuits will cause current of positive-and negative polarity to flow through the windings of the relays SIR! and DRGI respectively, thereby causing the polar rectional relayDRGI assuming itsleft-hand position, 'through front" contact 24 of this same relay, through polarcontact 25 of switch instruction relay SIRI assuming its right-hand position, through front contactifi of this same relay, and through switch box contact 03202 assuming its main track position, tothe common return'wire (3, connected to themid-point of the field battery. If the block in advance of the signal S3 had been occupied then trafiic conditions in advance of the si nal SI would have reflected caution trafiic conclitions and the signal SI would have assumed its caution position, in which position the signal contact C I assumes itsintermediate position and is also closed. 7

Let us now assume that the west-bound train enters upon the track section 2 and causes deenergization of the trackrelay ET. This produces no immediate result, for even though it closes-its back contact 32 this contact is included in otherwise open circuits and produces no current flow. Let us now assume that the westbound train passes the clear signal SI and treads upon the track circuit including the track relay IT, which occurs when the west-bound train passes over the points of the track switch Swl. This causesdeenergization of the track relay IT and the closure of its back contact 29 With the back contact 29 closed and with the contact blade C'I assuming either the clear or the caution position an energizing circuit for the upper winding of the indicationrelay OSRI may be traced as follows: beginning at the terminal plus of the batteryBB, contact 35 of the signal lever DGL! assuming its left-hand'position, the upper winding of the relay OSRI, back contact 29 of track relay IT, signal contact CI-of the signal SI assuming its clear or caution position, and over the common return wire C and to the midpoint. of the battery BB. This circuit is only momentarily closed because the dropping of the track relay IT causes the signal SI to be operated toitsstop position by the opening of front contact .22 of the track relay IT. During this momentary closure of the circuit for theupper wind- I ing of the relay OSRI, just-traced, this indication relay OSRI will be operated toits energized position and will then be maintained energized through a stick circuit including the contact 35 of, the signal lever DGLI and the stick contact 30' of this relay OSlP-A, so that this relay will remain energized until its stick circuit has been broken by manual movement ofthe lever DGLI. With the indication relay OSRI energized and its front contact 3l closed the indicating lamp 08! at the east end of the miniature track layout is energized and illuminated and manifests to the operator that the west-bound train has moved over the points of the track switch SwI. As soon as the operator has been informed of the movement of the west-bound train over the points of the track switch SwI he will return his signal lever DGLI to its normal middle position which causes the interruption of the stick circuit for the relay OSRI .by the opening of contact of the traced as follows: beginning at the terminal signal lever 'DGLI and will cause deenergization of the signal .relay DR(3rI.,- The breaking of this stick circuit for the relay OSRI; will, ofcourse, cause this relay to assume its .deenergized retracted position in which position the front contact 31 of this relay is open. I

Let .us now. assume that all of the apparatus has been returned to its normal condition and that a similar westebound train is'now approaching and that the operator desires this trainto move into the side track 5 of the passing siding PS; 7 In orderto. accomplish this the operator will operate his direction signal lever DGLI to the left,signifying,that west-bound trafficis to move over the track switch SwI, and which results in energization of the signal relay'DRGI to its left-hand position. The operator will simultaneously operate his: switch instruction lever SILII to .the left-hand position which signi fies thereverse position for theswitch and results in energization of the switch instruction relay SIRI to its left-hand energized position. With both of the relaysSIRI and DRGI energized to the left an energizing circuit for thelamp in the search-light signal SlA.is.c1osed which may be of a suitable source of current located at the field station, front contact 40 of the relay SIRI, polar contact dI of this same relay assuming its left-hand position, front contact 42 of the relay DRGI, and polar contact 43 of this same relay assuming its left-hand position through the lamp of the signal SIA to theother terminal ()f of said source of current. The normally dark signal SIA is now lighted and displays by a color, such as. red, the letter S instructing the :train crew to operate the track switch Swl to its reverse position- As soon as this track switch has been.

reversed and the switch box contact CSwZ has been moved to its lower position a circuit for the mechanism of the signal 'SIA, which maybe traced as follows, is closed: beginning at the terminal the mechanism of signal SIA, polar contact 45 of the relay DRGl' assuming its left-hand position, neutral contact 46 of this same relay,-switch box contact CS w2 tothe other terminaliC) of this same source of current. The flow of current in this circuit will operate the mechanismof the signal SIA to its proceed posi tion causing it to emit a proceed lightbeam, such as yellow, informingthe engineer that he may move his train intothe siding ,5. I ,:Let us nowiobserve howthe movement of the train into the side track is indicated in the central o ifice. With the track switch assuming its:

relay IT is 'deenergized causing closure or its I back contact 29 unless it was already closed by strain on the main track. If there was a waiting east-bound train on the main siding section the closure of the prepared circuit took place when the track switch SwI was operated to the takesidingposition by the train crew of thewestbound train. This closure of the last of the three contacts 29 CSwI and 32 results in closureof the prepared circuit hereto-fore mentioned, which I may be traced as follows: starting at the terminal of the battery BB, contact 35 of the lever DGLI assuming its left-hand position, upper winding of the indicating relay OSRI, line Wire f8, back contact 29 of the track relay IT; switch box contact CSw'l, back contact 32 of the track relay 2T, to the common return wire C connected to the mid-point of the battery BB. The completion of this circuit will, of course'cause energizati'on of the indicating relay OSRl, which relay will then remain energized through a stick circuit including its stick contact 35 As soon asth'e train has fully entered the side track 5 theoperator may extinguish theindicating lamp OS! by returning the signal lever DGLI to its middle normalpcsiti'on. The operator will, of

course, also return his switch instruction lever SILT to its normal right-hand position as soon as he is informed that the train has passed the tak'e siding signal 85A, and the train crew will have standing instructions to always return the track switch to the normal main track position 'as soon as a train which passed into or out of the side track has completed its movement.

Let us now assume that there is an east-bound 'tr'ainmoving in the mainsiding section t of the passing siding PS and that the operator wishes this train to continue its movement into the single track stretch including the main track section 2. In order to allow the movement of the east-bound. train into the section 2' the oper ator in the central ofiice will leave the switch instruction lever SI-Ll in its right-hand position and'will move the signal lever DGLI into its right-hand position, signifying east-bound trafiic. With both of these levers assuming the righthand positions the relays SIRI andDRGl at the field station will assume their right-hand energized position. With the relays SIR'I and SRGI' both energized to the right and with the track switch Swl returned to its main track position, a proceed circuit for the signal S2 is closed which may be traced as follows: beginning at the line wire 55 which is controlled in accordance with traflic conditions in advance and is connected to-either thefiplus or the minus terminal ofthe field battery depending upon whether traf- -fic conditions in advance of the signal S2 are clear or caution respectively, through the front contact 51 of the track relay 2T, through the mechanism of the signal 'SZ, through'polar contact 23 -of relay DRGI assuming its right-hand position, through the neutral contact 2 3 of this same relay, through polar contact 25 of the relay SIR! assuming its right-hand position, through neutral front contact 26 of the relay SIRI, through switohbox contact CSw2,to the common return wire C, connected to the mid-point of said field battery. The east-bound train may now proceed into the section 2 at either high speed or at caution speed depending upon whether the signal S2 is indicating clear or caution which depends on 'tra'ffic conditions in advance.

Let us now observe how the operator in the central ofice is informed of the movement of the'east-bound train over the points of the track switch Swl. As the east-bound train passes over the insulating joints 19 adjacent the track battery IB, the track relay IT is deenergized causing closure of its back contacts 29 The closure of contacts 29 will prepare a circuit for the indication relay OSR! which circuit is still open at another pointand which will be traced hereinafter. It should be observed that since the signal S2 is in either its clear or its caution position its semaphore contact C2 is closed which prepares said circuit at another point. As the east-bound train now passes the signal S2, this signal indicating either clear or caution, the track relay'2T is deenergized causing closure of its back contact 32 which results in closure of the following circuit: beginning at the terminal of. the battery BB in the central oflice, contact 35 of the lever DGLI assuming its righthand position, upper winding of the indicating relay 0333!, line wire 18, back contact 29 of track relay HT, semaphore contact C2 of the signal S2, back contact 32 of the track relay 2T, to the common return wire C connected to the mid-point of the battery BB. The closure of this circuit will of course result in the energizestion of the indicating relay OSRI and in the i1- lumination of the indicating lamp OSI. Shortly after dcenergization of the track relay 2T the circuit for the upper winding of the indicating relay OSRI will be broken at the semaphore contact C2 of the signal $2. This will, however, not cause deenergization of the indicating relay OSRI because this relay is held up through its stick circuit including the stick contact 30 As soon as the operator has been informed of the movement of the train past the signal S2 he will return his signal lever DGLI to its middle position thereby causingdeenergization of the signal relay DRGI and extinguishment of the indicating lamp OS! sothat the signal S2 will not be returned to proceed when the east-bound train gets beyond the control track circuits for the signal S2. The operator in the central oflice is therefore informed of the movement of the east-bound train over the switch points of the track switch Swl.

Let us now assume that there is an east-bound train standing on the section 5 of the side track of the passing siding PS and that the operator wishes this train to proceed into the single track section 2. In order to accomplish such movement of the east-bound train the operator will move his switch instruction lever SE! to its left-hand position and move his signal direction lever DGL! to its right-hand position, which will cause the relays SIR! and DRGI at the field station to assume their left-hand energized position and their right-hand energized position, respectively. It should be remembered that the signal SEA is normally a dark signal which signifies to the train crew that they may not operate .the track switch to the reverse position. With the relays SIR! and DRGI energized to the left and to the right, respectively, the following circuit for the lamp in the signal 52A is closed: starting at the terminal of the field battery, front contact 48 of the relay SIRI, polar contact 4: of this same relay assuming its left hand position, front contact 42 of the relay DRGl, contact 453 of this same relay assuming its right-hand position, the search-light lamp for the signal SZA to the other terminal of the field battery. The illumination of this signal SZA will display in the red the letter S which instructs the train crew to operate the track switch Swl to its reverse position. As soon as manual operation of the switch Swl to its reverse position has been completed and the switch box contact CSwZ has been operated to its lower position the following circuit for the mechanism of the signal SZA is closed: beginning at the terminal or of the field battery, depending upon trafiic conditions in advance, line wire 50 front contact 51 of the track relay 2T, mechanism of the signal S2A, polar conta'c't 45 of the relay DRGJ assuming its right-hand position, neutral contact 46 of this same relay and switch box contact CSwZ assuming its side track or lower position to the common return wire C connected to the mid-point of the field battery (not shown). The signal S2A will now indicate either clear or caution (green or yellow) depending on traffic conditions in advance and the east-bound train may'move off of the side track 5 and into the single-track stretch 2 in response to the proceed indication of the signal SZA. r

Let us now observe how the operator in the central ofiice is informed of this movement of the east-bound train oil of the side track and into the track stretch 2. As the train passesover the insulating joints H) at the east end of the track section 5 of. the side track it causes shunting and deenergization of the track relay lT which'causes closure of back contact 29 of this track relay. This prepares a circuit for the indicating relay OSRI which circuit will be traced when closed. As the east-bound train now proceeds over the track switch Swl, and assuming traihc conditions in advance to be clear, as it passes the insulating joints to adjacent the 'signal SZA it will cause shunting and deenergization of the track relay 2T. This results in closure of back contact 32 of this track relay and 010- sure of the prepared energizing circuit for the indicating relay O-SRI which may be traced as follows: starting at the terminal of the battery BBjcontact 35 of the lever DGLI assuming its right-hand position, upper winding of the indicating relay OSRI, line wire I8, back contact 29 of the track relay IT, switch box contact 0810!, back contact 32 of the track relay 2T to the common return wire C connected .to the midpoint'of the battery BB. The'closure of this circuit will of course result in the energization of the indicating relay OSRI, which relay upon assuming its energized position will close the stick circuit including the stick contact 30 The indicating lamp OS is of course now energized and informs the operator that the east-bound train has proceeded into the single track section 2. The operator may now return his signal lever DGLI to its middle position and the switch instruction lever SILI to its normal right-hand position so that the signal SZA will again become a dark signal to prevent a second train following the east-bound train just considered. The train crew will of course return the track switch Swi to its normal main track position in accordance with standinginstructions.

It is of course understood that the method of transmitting controls and indications to and from the field station with respect tothe oflice depends on local conditions and it should be understood that a code type centralized trafiic controlling system such as shown in the patent to Hailes and Brixner No. 2,259,561 granted October 21, 1941, may be used instead of the unit line wire construction shown, if desired.

Structure of Fig. 2

In Fig. 2 of the drawings has been illustrated a modified form of the present invention. It will be observed that in the structure of Fig. 1 the main siding section of the passing siding PS is provided with insulating joints IE] near the mid-point of this main siding section, whereas in Fig. 2 a center fed track circuit including only a battery-4B-IB connected across the mid-point of this main track is shown. In other words, in

the Fig. 12' structure the additional insulating a directional stick relay SR2 having a. back ooh-' I I tact 55 included inseries with the switch box contact C810! is employed inthe Fig. 2 structure.

Aside'from the differences 'just-mentioneivand. theiprovision of circuits "for the directional stick] relay SR2, the structures of Fig. '1 and Fig. 2 are identical, and therefore like parts and devices have been designated by like reference characters.

ril stick relay saz is provided with a pick:

up' circuit which'may be traced from the terminal plus of'thefield battery, back contact 56 of the track relayfilT, back Icontactj'fl. of the track relay 2T, semaphore contacts C2 "or (32A depending upon whether the signal S2 or thesig nal SZA is assuming a proceed position and wind-.

, ing of the stick relay SR2 and'back to the other terminal of the field battery. The stick contact 58 of the track relay 2'1 and stick con-,

ing and to the terminal minus It will. be readily observed that if an'e'astbound train which just passed off of the side track 5 over the fouling section andinto the single track section 2 should still bevstanding on the track section 2 and hold'the track relay 2T deenergized, and also assuming that the train crew has not yet, possibly for lack of time, returned the track switch Sw'l to its main track position the de-energization of the track relay IT-by the movement of either a west-bound train off of the siding or an east-bound train moving 01f of the track section 3 and over the track switch $103,

tact 59 of the stick relay SR2, through its windwhich might possibly cause deenergization of the.

track relay IT, that no movement of th train over the switch points of switch Swl will be indicated in the central office by illumination ofthe indicating lamp OSI in the Fig. 2 structure even if the track relay IT did drop, because the energizing circuit'for the indicating relay OSRI, which otherwise would have been completed, will not be completed by reason of the open back contact 55 of the directional stick relay SR2. In

order to get a more clear understanding of this feature of the modification illustrated in Fig. 2 a few train operations will be considered.

'Let us assume that there is an east-bound train at the east end of'section 5 of the side track of passing siding PS and that there is also a westbound train on the west. endv of this section 5 which could, for instance, bea work train which backed into this section. As the crew of the eastbound train in'res'ponse to the appearance of the letter S on the signal SZA operates the track switch Szcl to the reverse position the switch'box contact CSwl is closed, itbeing of course understood that the operator has operated his levers SILI and DGLI to the left and right, respectively. This will of course cause the signal SIA 1 case. This will ,cause dropping of the track relay IT followed by dropping of the track relay ET and since the switch box contact C810! and the back contact55 of the directional stick relay SR2 (see Fig. 2) are now closed a pick-up circuit for the indicating relay OSRi is completed which is readily traced in the drawings. This will cause the illumination of the indicating lamp OS! in the central ofiice to inform the operator that the east-bound train has moved off of the side track and out of the passing siding PS. It is of course understood that movement of the east-bound train out or the passing siding PS will result in the energization of the directional stick relay SR2 after the indicating relay OSR! was energized. This energization of the directional stick relay SR2 is somewhat delayed because this relay SR2 is slow acting, this directional stick relay SR2 being picked up through its pick-up circuit closed while the track relays IT and 2T are deenergized and so long as the contact CZA of the signal SZA remains closed. The directional stick relay SR2 when once up is of course stuck up through a stick circuit including the back contact 58 of the track relay 2'1 and remains stuck up so long as the east-bound train is in the track section 2.

Let us now assume that the operator returns his signal lever DGLI back to its normal and middle position resulting in the extinguishment or the indicating lamp OS! and for some reason or'other, as for instance in order to set up a signal indication for the east-bound train to make a back-up move into the main siding section of the passing siding PS, returns the lever DGLI to either extreme position. Let us assume that the train crew has not yet had time to return the track switch Swi to its normal main track position. If now the west-bound train moves off of the passing siding PS and into the single track section 3 and if such movement results in the deenergization of the track relay lT,'this movement of the west-bound train will not cause an indication to be given reflecting the movement of a train over the switch points at the east end of the passing siding PS, because the back contact 55 of the directional stick relay SR2 is now open. In other words, even though a center fed track circuit is employed on the main siding section of the passing siding PS hav- ..g the same as, for instance, by the employment of a code type communicating system instead of a unit line wire .control and indication system, without departing from the spirit or scope of the invention except as demanded by the scope of.

the following claims.

What Iclaim as new is 1. In combination with a railway track including a passing siding consisting of a side track and a main siding section adjacent thereto and connected to two single track stretches by two ing a track relay at each end thereof and of such construction that both track relays are deenergized if a train enters either end of the track circuit the indications of train movement over the points of a track switch will only be given for that end at which a train actually passes over the points of the track switch.

The applicant has thus provided a rather simple centralized trafiic controlling system together with means for positively instructing the train crew to operate a track switch by hand and has further provided means for indicatin the movement of a train over the points of a track switch without the employment of the usual detector track circuit and its additional track battery, track relay and insulating joints.

Having thus shown and described several specific embodiments of applicants invention it is desired to be understood that these embodiments have been selected for the purpose of disclosing the nature of the invention and the functions which it performs and it is desired to be understood that Various modifications, changes and additions may be made to adapt the invention to the particular problem encountered in practictrack switches; signals associated with each of said track switches for governing the movement of traffic in both directions over such track switches; a first track circuitincluding a source of current and a track relay for the main siding section and extending from one pair of switch points to the other pair of switch points of said track switches; a track circuit including a track relay for an adjacent section of each of said single track stretches; and means for each track switch controlled by contacts reflecting the .conditions of said first track circuit, by contacts of the track relay for the adjacent track section of the adjacent single track stretch, by contacts of the adjacent track switch and by contacts of the signals associated therewith, for manifesting when a train moves over such particular track 7 switch.

2. In combination with a railway track including a passing siding consisting of a side track and a main siding section arranged side by side and connected to two single track stretches by two track switches; signals associated with one of said track switches for governing the movement of traffic in both directions over such track switch; a first track circuit including a source of. current and a track relay for and extending substantially half the length of the main siding section; a second track circuit including a source of current and a track relay for an adjacent section of the single track stretch associated with said one track switch; and means controlled by contacts reflecting the conditions of the two track relays, said one track switch and certain of the signals associated with said one track switch for manifesting when a train moves over said one track switch.

3. In combination with a railway track including a passing siding consisting of a side track and a main siding section adjacent thereto connected to two single track stretches by two track switches; signals associated with each of said track switches for governing the movement of trafic in both directions over such track switches, a center fed mainsiding section track circuit including a source of current connected across the rails near themiddle of the main siding section and a track relay at each .end of said main siding section; a track circuit including a track relay for an adjacent section of each of said single trackstretches; and means for each track switch controlled by contacts of such track switch, by contacts reflecting the conditions of the track relays adjacent that track switch and by contacts controlled by the adjacent signals, for manifesting when a train moves over that particular track switch. h

4. In combination with :a railway track including a passing siding consisting of amain siding section and a side track in multiple connected to two single track stretches by track switches; signals associated with one of said track switches for governing the movement of traffic in both directions over'such track switch; a firsttracl:

circuit including a source of current connected a'crossthe rails near a mid-point of said main siding section and a track relay nearsaid one track switch; a track'c'ircuit including a'source of current and a track relay for an adjacent section of thesingle track stretchassociate'dwith said-one track switch; and means controlled by contacts reflecting the conditions of the two track relays-said one track switch and certain of the signals associated with said one track switch for manifesting when a trainmoves over said one track switch.

' 5; In combinationwith a railway track including a passing siding consisting of a main siding and a side track in multiple therewithconnected to two single track stretches by trackswitches; signals associatedwith one of said trackswitches for governing themovement of traflic-in both directions .over suchtrack switch; "insulating jointsnear the middle'of saidmain-siding to divide it into twot'siding sections; a'first trackcircuit including a source of/current connected acrosscthe track rails near said insulating joints but a direction toward one iof said track switches and a track relay connected across the track rails ofthe main "siding section adjacent saidbne, track switch; a track circuit including a sourceof currentand a track relay ioran-iadjacent section of the single 'track .stretch associateduwith said one track. switch; and means controlled by contacts reflecting the conditions of the two track relays, said one track switch and certainoi said signals associated with aid one tract: switch for manifesting when a train moves oversaidone track switch. j s 6, In-combination with a railway trackincluding amassing siding consisting of a main siding and a side track in multiple therewith connected to'two single track stretches by track switches; signals associated with one of said track switches for governing the movement of trafficin both directions over such track switch;. insulating joints; near the middle ofv said main siding for dividing it into'two siding sections; a firstfltrack circuit including a source of current connected acrossthe track rails near said insulatingjoints but in a direction toward. one; of said track switches and a track relay connected across the track railsof the main siding section adjacent said one track switch; a track circuit including asource'of current and a track relay Vforan adjacent section of the single track stretch associated with said one track switch; and means controlled by contact reflecting. the conditions of the two track relays, the position assumed by aid one track switch and the conditions of certain of said signals associated with said one track switch for momentarily-closing a circuit' to momentarily manifest the movement of a train over said onetrack switch. v .v

"7. ln combination with a railway track including. a passing siding consisting of a side track and a'rnain siding section adjacent thereto and .conn'ected to two single track stretches by two track "switches; signals associated with each of said track switches for governing the movement of traffic in both directions over such track switches; a first track circuit including a source'of current and track relay means for the main siding section andextending from one pair of switch points to the other pair of switch points of said track switches; a track circuit including a track relay for an adjacent section of each of said single track stretches; and means for each track switch including a stick relay and including con- 8; Incombination' with a railway track including a passing siding consisting of a main siding section and aside track arranged inmu'lt'iple and connected to two 'single track stretches by two track switches;- signals associated with each of said track switches for governing the movement of traffic in both direction over such track switches; a-centerfe'dmain trackcircuit including a source of current connected across thetrack rails near the middle of the main siding section and a track relay at eachen'd of said ma'in' siding section; a second track circuit including a track relay for an adjacent section of each otsaids'inglc track stretches; and means ior'each track switch including astick-relay and including contacts reflectingthepositions of the c associated track switch; contacts refiecting the conditions of the adjacenttrack relays and cone tactslrefiect'ing. the conditions of the 'signalsas sociated with that track switch, for manifesting when a train moves over the 'points of such par ticular switch.

9 In combination with a railway track including' a passing siding consistingof amainsiding section and aside track arranged in multiple and connected to two single track stretches'by two track switches; signals associated with each ofxsaid track switches fongovernin-gthe movement of trafiic in both directions over such track switches; a first trackcircuit including a source of; current and a track relay for the main siding section and extendin from one pair of switch points to, the other'pair; oflswitch points ofsaid track switches; a second track circuit including a-track relay for an'adjacent section of each of said single track stretches; a stick relay having a pick-up circuit closed momentarily as a train moves over one of said track switches in a direction into the adjacent single track stretch and having astick circuit including a back contact of thetrack relay of the said adjacent section of said adjacent single track stretch; and means. including said stick relay and also including contacts reflecting the positions of said one track switchand the conditions of the signals and track relays adjacent to said one track switch for manifesting when a train moves over said particular ciated with one of said track switches for governing the movement of traflic in both directions over such track switch; a first track circuit including a source of current and a track relay for the main siding section; a second track circuit including a source of current and a track relay for an adjacent section of the single track stretch associated with said one track switch; and'circuit means including three circuits for manifesting the movement of a train over said one track switch of which the first includes contacts closed when the signal governing trafiic in one direction over'said one track switch in its. normal position indicates clear and the track relay for the main siding section assumesits deenergized position, of: which the a second circuit includes contacts closed-when the-signal for governing traffic in the opposite direction oversaid one track switch in its normal position indicates clear and both the track relay for the main track and the siding section relay for an adjacent ticn of the adjacent single track stretch, assume their deenergized position, and the third circuit ofwhich includes contacts closed: when said one iracl; switch assumes its reversed position and both; the track relay forthe main siding section and the trackrelay for said adjacent section ofsaid adjacent single track stretch assume their; deenergizedposition.

ll. In combination with a. railway track in cluding a passing siding consisting of a main. siding section and a sidetrackarrangedfin multiple therewith and connected togtwo; single track stretches by track switches; signals associated with one of. said track switchesv for governing the movement of traffic inbotn directions oven such trackswitch; a first track circuit including a source of current and a trackrelay for the. main siding section; a second track circuit in: cluding a source of current and a track :relay. for an. adjacent section. of the single track stretch adjacent said one track switch; circuit: means including three circuits. for manifesting; the movement of a train over said one track switch of which the first includes contacts closed: when the signal governing trafiic-in one direction: over said one track switch in its normal position indicates clear and the track relay for the main siding section assumes its deenergized position, of which the second. circuit includes contacts closed when the signal for governing trafiic in the opposits direction over said? one track switch in its normal position indicates clear and both the track relay for the main siding section and the track relay for an adjacent section of the adjacent single track stretch assume their deenergized position, and the third circuit of" which includes contacts closed when said one track switch assumes its reversed position and boththe track relay for themain siding section and the track relay for saidadjacent section of said-adjacent single track stretch assume their deenergized position; a local control office; line circuits connecting said ofiiceand said one track switch; means at said control oiiice for controlling" said signals over said linecircuits; and indication means at said office controlled by said circuit means and over said line circuits.

12. In combination with a railwaytrack; including a passing siding consisting of a main siding section and a side track arranged side by side and connected to two single trackstretches by two track switches; signals associated with each of said track switches for governing the movement of traffic in both directions over such track switches; a first track circuit including a source of current and a track relay for the main siding section and extending from one pair of switch points to the other pair of switchpoints of said track switches; a track circuit including a second track relay for anadjacent section of each of said single track stretches; a stick relay for each track switch having a. pick-up circuit closed when a train moves over-the associated track switch in a direction toward theadjacent single track stretch and having a stick circuit including a contact closed so long as said adjacent section. ofsaid adjacent single 'track stretch is occupied; and circuit means including three circuits for each traclcswitclrfor manifesting the imavlement" of: a. trainvover such track switch of which; the firstv includes, contacts closed: when. the, signal gprer-ningztraific in one direction oversaid one track switch: its normal; position indicates clear and: the track; relay for the main sidin section assumes, its; deenergized position, of; which the. second: circuit includes contacts; closed,- when; th signal.- fcr: gov r ing trafiic; in, t e no site dii ection; Otter uchrack. swit h in, thenormai coa ti n:indicates-decre d o h the track relay; for nelmain sidin e ion; nd the; traclsrelalltor an. a iacen-t section. of th adjacent, single. track stretch assume their deenergized position, n hehird circuit: of. whi h includes; contacts closed when such; track, switch; assumes; its 1382'. verse p siti n/ aid stick: relay assumes its en-- ergizemposition, and both theqtrack relayfor the ainsidingsectionand the. trackrelayror said dia ent section of said a iacent; single track; stretchassume; their deenergized position.

13.. combination. with a. railway track. imuding :a gassing: siding; consisting orza main idin sectionandca side track connected to two sin le track. stretches bytwotrack switches; Sig nalsrassociated with each of said: track switches for goyemmg' the incitement ofi trafiic in botln directionsorer such. track switches; a first trackcirciu'tcincluding aisource or? current and a track relay; tor the; main; siding section and extending from: one pair oiiiswitch. points to the other pain on switch points of: said track switches; a track' circllitincludingg asecond track relay for an adja cent sectionzofi eachofisaid single track stretches: asticir relay'for; each track switch and having a pickrup; circuit. closed when a train moves over the associated track switchdn a direction toward the aduacent single track stretch and having a stick circuit including a contact of thetrack relityflfi the .track circuit. of said adjacent section of said; adjacent single trackstretch; circuit means: including three-circuits for each track switchgformanifesting the movement ofa; train over: such trackswitch of which the first includes contacts-closed: when the signal governing tr-aflic in one direction. over said one track switch in itsinormal position indicates clear and thetrack relay: for the-main siding section assumes its deenerglzed; position, of. which the second circuit incllldescontacts; closed when the signal for governingrtrafiic inethe opposite direction over such track switch: in the normal position indicates clear and: both the track rela for the main siding-:sectionrand' the track relay for an adjacent section of the adjacent single track' stretch assume their .deenergized position, and the third circuit of? which includes contacts closed when such ttrack'iswitch assumes its reversed position, said. stick relay. assumes its deenerg-izedposition, and both the track relayfor the main siding section. and? the track relay: for said-adjacent section of said adjacent single track stretch assume-their deener-gized position; a local office; line circuitsdoonnecting said office' andysuchtrack switch; means at said control office for controllin said signals over said line circuits;- and indication-means at said-office controlled by'said circuit means and oversaid-line circuits.

1A; In combinationwith a -ailway track .including a passing siding consisting of a main siding section and a side track connectedto two single tracki stretches by two trackswitches; signels associated with. each-cf said track switches fme'gouerning the movementiof traffic in botlrdinecticns over such\ track switches; a first track cincuittiincludhigza source: oficurrent and a track relay- :or -the;.smaim siding: section: and extending from one pair of switch points to the other pair of switch points of said track switches; a track circuit including a track relay for an adjacent section of each of said single track stretches; a stick relay having a pick-up circuit closed inomentarily as a train moves over one of said track switches in a direction into the adjacent single track stretch and having a stick circuit include. ing a back contact of the track relay of; the track circuit of said adjacent section of said adjacent single track stretch; and means including said stick relay and also including contacts reflecting the positions of said one track switch and the conditions of the signals and track relays adjacent to said one track switch for manifesting when a train moves over said particular track switch. a v

15. In combination; a track switch connecting either a main siding section or a side track toa single track switch, a signal for governing trailic oil of the side track into the single track stretch including a movable color screen, a cover glass having operating instructions thereon which are visible only when light is emitted from said cover glass and an electric incandescent lamp back of said color screen and cover glass and giving instructions to operate said track switch to the side-track position; a central ofiice remote from said track switch; an electro-responsive device for governing the operation of said color screen in accordance with trafi'ic conditions in advance and displaying a danger indication when said electro-responsive device assume the deenergized position; control means including a control circuit extending from said ofiice to said track switch for governing the illumination of said lamp; and contacts in the control circuit of said electro-responsive device closed only when said track assumes the side track position; whereby upon illumination of said lamp by an operator at said office when said track switch assumes the main position causes said signal to indicate danger and display said instructions to operate the track switch to the side track position and whereby upon operation of said track switch to the side track position said signal assumes a more favorable position if trafiic condi-' tions in advance are favorable.

16. In combination, a track switch for connecting the main siding section or the side track of a passing siding to a single track stretch, a multiple aspect signal for instructing the train crew to operate said track switch to the side track position and to govern the movement of traffic off of said side track and into said single track stretch in accordance with conditions of trafic in said single track stretch, a central oflice, a line circuit extending from said oflice to said track 17. In combination, a track switch for connecting the main siding section or the side track of a passing siding to a single track stretch, a multiple aspect signal for instructing the train crew to operate saidtrack switch to the side track position and to govern the movement of traffic off of said side track and into'said. single track stretch in accordance with conditions of trafic in said single track stretch, .a central office, a

line circuit extending from said office to said nal to display a proceed aspect effective only-if said line circuit is energized, traiiic condition in said single track stretch are favorable and said track switch assumes the side track position.

i 18. In combination, a track switch for connecting the main siding section or the sidetrack of a passing siding to a single track stretch, a multiple aspect take-siding signal for instructing the train I crew to operate said track switch to the side track position and to govern the movement of traific off of said single track stretch and into the side track of said passing siding, a central oiiice,.a line circuit extending from said oflice to said track switch, means for controlling said takesiding signal through the medium of said line.

circuit from said central ofiice to display an aspect instructing the train crew to operate said track switch from its main siding position to its side track position, and means for causing said signal to display a proceed aspect efiective only if said line circuit is energized and said track switch assumes the side track position.

19.In combination, a track switch for connecting the main siding section or the side track of a passing siding to a single track stretch, a multiple aspect take-siding signal including a movable spectacle multi-color screen and an electm-responsive device for operating said spectacle and a normally extinguished electric lamp back of said screen for instructing the train crew to operate said track switch to'the side track position by the illumination of said lamp and to govern the movement of traiiic off of said single track section and into the side track of said passing siding in accordance with the position assumed by said spectacle, a central ofiice, a line circuit extending from said oilice to said track switch, means partly in said ofiice and partly at said track switch for illuminating the lamp of said take-siding signal by energizing said line circuit to display an aspect instructing the train I crew to operate said track switch from its main siding position to its side track position, and means for controlling said electro-responsive de.

vice to display a proceed aspect effective only if.

said line circuit is energized and said track switch assumes the side track position.

SEDGWICK N. WIGHT.