US2697778A

US2697778A - Railway traffic controlling apparatus

Info

Publication number: US2697778A
Application number: US285208A
Authority: US
Inventors: Charles M Hursh
Original assignee: Westinghouse Air Brake Co
Current assignee: Westinghouse Air Brake Co
Priority date: 1952-04-30
Filing date: 1952-04-30
Publication date: 1954-12-21
Anticipated expiration: 1971-12-21

Description

Dec. 21, 1954 c. M. HURSH RAILWAY TRAFFIC CONTROLLING APPARATUS Filed April 50, 1952 2 Sheets-Sheet 1 n N a z 7 L n? Eh M m #J m n U 7 w 5 6H z N M S 5 7 w E E 9 u m w m XE m 9 2 M r $l F i P 1. V w Z 5 A W w A m r 2 w hwfi f F W u /W ngm y 9 B Fig, la;

INVENTOR.

@harles M Harsh By no .LM. m I

.EIIS A CITORNEY 2 Sheets-Sheet 2 Slfiatian D llllllll I- INVENTOR. Charles M Hans-I2 Dec. 21, 1954 c. M. HURSH RAILWAY TRAFFJ IC CONTROLLING APPARATUS Filed April 30, l952 Dll I 5110 5 1N6? fiz G Fig: 112.

RAILWAY TRAFFIC CONTROLLING APPARATUS Charles M. Hursh, Turtle Creek, Pa., asssignor to Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application April 30, 1952, Serial No. 285,208

13 Claims. (Cl. 246-26) My invention relates to railway trafiic controlling apparatus. More particularly, my invention relates to apparatus of the type which is known as traffic locking apparatus, by means of which, traffic governing devices, such, for example, as signals for any given stretch of railway track are in part manually controllable, for governing trafiic movements in both directions, and by means of which the traffic governing devices, after being controlled for governing traffic movements in one direction or the other over the stretch of railway track, cannot be controlled for governing trafiic movements in the opposite direction while the stretch of track is occupied by a train, or while a traffic governing device such, for example, as a signal, is controlled for authorizing a train to proceed in the former direction onto the stretch of track.

The form of apparatus embodying my invention, as shown in the accompanying drawings, requires joint action by persons at two different control stations, one for each end of a corresponding stretch of railway track, for manually controlling traffic governing devices for directing trafiic movements in either direction over the stretch of railway track. Each of the two control stations is provided with manually operable traffic control means, such, for example, as a trafiic lever, and with one or more manually operable signal control devices such, for example, as signal levers, for controlling signals for governing traflic movements onto the corresponding end of the stretch of railway track.

In some forms of traffic locking apparatus, a trafiic control circuit arrangement has been employed in which polar traific control relays are energized in series by current of one polarity or the other in a cicuit which includes a plurality of track relay contacts, one for each of a plurality of track sections into which an associated stretch of track is divided, and in which the traffic control circuit is controlled from only one control station. With such an arrangement, the polar traffic control relays are deenergized while any one of the track sections of the associated stretch of track is occupied. The contacts of one or more of the polar traffic control relays can therefore at times become misplaced by an induced surge of foreign current while the trafiic control circuit is open due to occupancy of the stretch of track by a train.

An object of my invention is the provision of novel and improved traffic locking apparatus in which a change of polarity of energization of the polarized trafiic control relays for an associated stretch of railway track can be effected only by joint action of persons at two different control stations, one for each end of the associated stretch of railway track, and only while the stretch of track is unoccupied, and while trafiic governing devices such, for example, as signals for governing traflic movements onto the stretch of track in opposite directions are controlled to stop such traific movements.

A feature of my invention for accomplishing this object is the provision of a block indication control circuit including a neutral block indication relay for a given or first one of the two control stations connected in series with a polarized block indication relay for the other or second control station, and including manually controllable traflic control means for the given control station for controlling the polarity of energization of the polarized 'block indication relay for the other control station, and

also including front contacts of locking andtrack relays for the associated stretch of track.

Another feature of my invention for accomplishing the I object stated is the provision of a polarized traffic con- United States Patent ICC trol relay for each of the two control stations connected in multiple with each other in a traffic control circuit which includes neutral and polar contacts of the polarized block indication relay and which also includes contacts which are manually controllable from the second control station.

Another object of my invention is the provision of means for keeping the polarized traffic control relays energized, and for preventing reversal of the polarity of energizing current supplied to the polarized trafiic control relays while the associated stretch of track is occupied by a train or while signal control apparatus is in condition for controlling a signal to display a proceed indication for a train to enter the associated stretch of track.

A feature of my invention for accomplishing this object is the provision of retaining circuit means for the polarized traffic control relays including a back neutral contact of the polarized block indication relay and a front neutral and normal and reverse polar contacts of the polarized trafiic control relay for the second control station.

Still another object of my invention is the provision of suitable indication means for each of the control stations which can be controlled to inform the leverman or dispatcher at the corresponding control station when the leverman or dispatcher at the other control station desires to change the direction of traffic movements, and to show, at other times, the direction of trafiic movements for which the apparatus is set up, and to also display a track occupancy indication if the stretch of track is occupied by a train or if one of the signals for governing trafiic movements onto the stretch of track at the opposite end is controlled for displaying a proceed indication.

A feature of my invention for accomplishing this object is the provision of indication means for each of the two control stations controlled by the manually operable traffic control means and by the polarized traffic control relay and also by the block indication relay for the corresponding end of the stretch of railway track.

I shall describe one form of apparatus embodying my invention, and shall then point out the novel features thereof in claims.

In the accompanying drawings, Figs. 1a and lb, when placed side by side, withFig. 1a on the left, constitute a diagrammatic view showing one form of apparatus embodying my invention for a stretch of main railway track a-d which is provided with signals for governing traific movements in opposite directions onto the stretch of main track; including a polarized trafiic control relay for each end of the stretch of track, connected in multiple with each other and normally energized by current of normal polarity; including a neutral block indication relay for a given or first end of the stretch of track connected in series with a polarized block indication relay for the other or second end of the stretch of track; and including indication means for each end of the stretch of track controlled by means including the trafiic control and block indication relays for the corresponding end of the stretch of track.

Similar reference characters refer to similar parts in the drawings.

Referring further to the drawings, a stretch of main railway track a-d is shown provided with signals, designated by the reference characters RA2 and RB2 for governing traffic movements onto the stretch of track in a given direction, from left to right, as shown in the drawings, which I shall assume is the eastbound direction, and is also provided with signals, designated by the reference characters LA4 and LB4, for governing trafiic movements onto the stretch of track in the opposite or westbound direction. As shown in the drawings, the stretch of main railway track ad is connected adjacent its end a by a switch 1 with an auxiliary track, designated by the reference character X, and is connected adjacent its other end d by a switch 3 with a second auxiliary track Z. A signal, designated by the reference character L2, is provided for governing westbound trafiic movements over switch 1 in its normal and reverse positions, and a signal, designated by the reference character R4, is provided for governing eastbound trafiic movements over switch 3 in its normal and reverse positions.

The signals may be of any suitable design such, for example, as the well-known searchlight type. Eachof the signals is provided with a mechanism, designated by the reference character G preceded by the reference character dor the corresponding signal, which is operable from a normal or zdeenergiaed position to one or more proceed positions. While eachmechanism G is deenergized, the corresponding signal displays a stop indication, and when Ytone of the mechanisms .6 tiszrnoved to a proceed position, the corresponding signal displays a proceed indication.

.Signal contactsndesignated by thezreference characters g and y, are operated in conjunction with each signal mecha- -nism G, :and arenormally closed-while the corresponding mechanism-G is in the :deenergized position, but are arrangedso thatcontact ;g :be opened when mechanism G. is moved to its clear proceed position and contact y will be opened twhen mechanism is moved to an approach proceed position.

.Operated in conjunction with switch 1 is a normal switch'contact, designated by the-reference character lt-nw, which is closed while switch 1 is in the normal position for traffic movements along the main track .a-d, as shown in the drawings, {but becomes opened when switch 1 is moved to its reverse position for traffic movements to or from auxiliary track ,X. A reverse switch contact, designated by the reference character lrw, is open while switch 11 is in the normal position, and becomes closed when switch 1 liS moved to the reverse position. Contacts 3nw and 3rw are operated similarly to contacts lnw and lrw, respectively, in conjunction with switch .3.

In .order to simplify the drawings, each track, comprising two parallel series of track rails, .is represented by a single line.

The stretch of track ta d is divided by insulated joints 7 into sections designated by .the reference characters 1T, 2T and 3T. Each of the track sections is provided'with a track circuit including a suitable source or current such, for example, as a battery :8, connected across the rails adjacent one end of the section, and a traffic responsivetrack relay, designated by the reference character R preceded by the reference character for the corresponding section, connected across the rails adjacent the opposite end of the section.

A given or first control station, designated by the reference character A, and a second control station, designated by the reference character D, .are associated with the west and east ends, respectively, of the stretch of railway track .a..d

A signal lever, designated by the reference character 2V, .a traffic lever, designated by the reference character SFV, and indication means shown as lamps, designated by the reference characters SBFK, SNK and SRK, are provided at control station A. A signal lever, designated by the reference character 4V, a traffic lever, designated by the reference character .6FV, and indication means shown as lamps, designated by the reference characters 6BFK, 6NK and 6RK, .are provided at control station D.

Each of the signal and trafiic levers has a normal control position, designated by the reference character 11, in which it is shown in the drawings, and has .a reverse control position, designated by the reference character r to the right of its position n. Each of the signal levers 2V and 4V has also .a second reverse control position 7 to the left of its position n.

Contacts operated in conjunction with the levers 2V, 4V, SFV and GFV are represented on the drawings by circles, in which are placed reference characters to show the positions of the respective levers in which the contacts are closed. Contact 52 of lever 2V, for example, shown in Fig. 1a of the drawings, is closed only while lever 2V is in the r position, as indicated by the reference character r in the circle for this contact. Contact 9 of lever 2V, as another example, is closed only while lever 2V is in the n position, as indicated by the reference character 21 in the circle for this contact.

A polar traflic lever repeater relay, designated by the reference character SFP, is controlled by lever SFV so that the polar contacts of relay SFP are in their normal position while lever SFV is in its 11 position, and are moved to their reverse position when lever SFV is moved to its r position. A polar trafiic lever repeater relay, designated by the reference character GE, is similarly controlled by lever 6FV.

A time locking stick relay, designatedby the reference character ZAS, for station A, is controlled by the contacts of signals RAZand RB2 and by contact f lever 2V.,and also by a contact of track relay 1TR and by a contact of a time element device, shown as a time element relay designated by the reference character 2TB. Relay 2TB also is controlled by the contacts of signals RA2 and RB2 and by contact 9 of lever 2V, and is controlled by a back contact of relay 2A8. A time locking stick relay, designated by the reference character 4A5, and a time element device, designated by the reference character 4TB, for station D, are controlled similarly to relays 2A8 and 2TE, respectively, for control station A.

A traffic locking stick relay, designated by the reference character ZES, for station A, is controlled by relays 2A8 and lTR. A traffic locking stick relay, designated by the reference character 4WS, for station D, is controlled by relays 4A8 and STR.

A neutral block indication relay, designated by the reference character 213?, for control station A, is normally energized in series with a polarized block indication relay, designated by the reference character 4BP, for control station D, over a circuit which includes front contacts of relays ZES, ZTR and 4WS. The polarity of energization of relay 4BP in this circuit is controlled by normal and reverse contacts of relay SFP.

A polarized traffic control relay, designated by the reference character SFR, for station A, is controlled in multiple with a polarized traflic control relay, designated by the reference character 6FR, for station D, over a circuit which includes polar contacts of relay 6P1 and neutral and polar contacts of relay 481 When relay 4BP becomes deenergized because of deenergization of one of the relays 2E5, ZTR and 4WS, relays SFR and 61 R are retained energized by current of the polarity by which they were last previously energized in a circuit which includes a back neutral contact of relay 4BP and neutral and polar contacts of relay 61 R.

Signal mechanisms RAZG and RBZG are controlled by contacts of lever 2V and switch 1 and also by a front neutral contact and a normal polar contact of relay SFR. Signal mechanisms LA4G and LB4G are controlled by contacts of lever 4V and switch 3 and by front neutral and reverse polar contacts of relay tiFR.

A flasher relay, designated by the reference character SFL, is provided for station A, having a contact 58 which is repeatedly opened and closed a predetermined number of times per minute while relay EFL is energized. A similar flasher relay 6FL is provided for station D.

Electric current for energizing the various control circuits at station A may be supplied from any suitable source such, for example, as a battery, designated by the reference character Q, and having terminals B and N, as shown in Fig. la. Electric current for energizing the indication lamps SBFK, BNK and 5RK can be supplied from any suitable source such, for example, as a battery, designated by the reference character EQ, having terminals desginated by the reference characters EB and EN, as shown in Fig. la. Similar sources of current, designated by the reference characters IQ and lEQ, are shown in Fig. lb for station D.

Having described, in general, the arrangement and control of the various parts of one form of apparatus embodying my invention, I shall now describe the circuits and operation in detail.

As shown in the drawings, all parts of the apparatus are in the normal condition, that is, all track sections are unoccupied, and therefore all track relays are energized; each of the switches 1 and 3 is in its normal position for traffic movements along the main stretch of track a-d; each of the signal mechanisms is deenergized, and is therefore in the stop position; each of the levers 2V, 4V, 5FV and 6FV is in its n position; relays 2A8, 2E8, 2BP, SFL, 4AS, 4WS and 6FL are energized; relays SFP, SFR, 6FP, 4B? and 6FR are energized by current of normal polarity; relays 2TB and 4TB are deenergized; normal indication lamps, designated by the reference characters SNK and 6NK are lighted; and indication lamps SBFK, SRK, 6BFK and 6RK are unlighted.

Relay ZAS, shown in Fig. la, is energized by a stick circuit passing from terminal B of battery Q, through contacts y and g of signal RA2, contacts y and g of signal RB2, contact 9 of lever 2V, front point of contact 10 of relay 2AS, and the winding of relay 2AS to terminal N. Relay 4AS, shown in Fig. 1b, is energized by 5 a stick circuit which is similar to the stick circuit just traced for relay 2AS.

Relay 2ES, shown in Fig. 1a, is energized by both a pickup and a stick circuit, the pickup circuit passing from terminal B, through contacts 17 and 18 of relays 2A8 and lTR, respectively, and the winding of relay 2E5 to terminal N. The stick circuit for relay 2ES is the same as the pickup circuit just traced except that it includes contact 19 of relay 2ES instead of contact 18 of relay 1TR. Relay 4W8 is energized by a pickup and a stick circuit which are similar to the pickup and stick circuits just traced for relay 2ES.

Relay SFP is energized by a normal control circuit passing from terminal B, through contact 23 of lever 5FV, and the normal control winding 24 of relay SFP to terminal N. Relay 6FP is energized by a similar normal control circuit passing from terminal 1B, through contact 27 of lever 6FV, and winding 28 of relay 6FP to terminal 1N.

Relays 2BP and 4BP are energized by a circuit passing from terminal B, through the winding of relay 2BP in multiple with a resistor I, contact 31 of relay SFP in the normal position,

contacts

32, 33 and 34 of relays 2ES, 2TR and 4WS, respectively, in the normal direction through the winding of relay 4BP, and contact 35 of relay SFP closed in the normal position, to terminal N.

Relays SFR and 6FR are energized in multiple with each other by current of normal polarity in a normal pickup circuit passing from terminal 1B, through contact 36 of relay 6FP closed in the normal position,

contacts

37 and 38 of relay 4BP, the winding of relay SFR in multiple with the winding of relay 6FR and a resistor I, contact 39 of relay 4BP, and contact 40 of relay 6FP closed in the normal position to terminal IN.

The resistors t are connected in multiple with the windings of relay 2BP and relay 6FR in order to make these relays slow releasing.

With relay SFR energized by current of normal polarity, indication lamp SNK is lighted by a circuit passing from terminal EB, through contact 48 of relay SFR, contact 49 of relay 5FR closed in the normal or lefthand position, and lamp SNK to terminal EN. Lamp 6NK for station D is lighted by a circuit which is similar to the circuit just traced for lamp SNK.

Flasher relay SFL is connected directly across terminals B and N, and is therefore constantly energized, and its contact 58 is repeatedly opening and closing. Flasher relay 6FL is connected directly across terminals 1B and 1N, and is therefore constantly energized, and its contact 63 is repeatedly opening and closing.

I shall assume that, with apparatus embodying my invention as shown in the accompanying drawings, an eastbound train is to move past signal RA2 onto the stretch of main track a-d. A leverman or dispatcher at station A will therefore move lever 2V to its r position, thereby opening its contact 9 and deenergizing relay 2AS. Lever 2V, upon reaching its r position, closes its contact 52, thereby completing a circuit for energizmg signal mechanism RA2G, this circuit passing from terminal B, through contact 52 of lever 2V, contacts 53 and 54 of relay SFR, contact lnw of switch 1, and signal mechanism RA2G to terminal N. Mechanism RA2G will therefore be moved to an approach proceed position.

When relay 2AS becomes deenergized, its contact 17 opens the pickup and stick circuits for relay 2ES, causing relay 2ES to also be deenergized. With relay ZES deenergized, its contact 32 opens the circuit previously traced for relays 2BP and 4BP, causing these relays to also in turn be deenergized.

With relay 2BP deenergized, indication lamp SBFK becomes steadily lighted by a circuit passing from terminal EB, through the back point of contact 62 of relay 2BP, and lamp SBFK to terminal EN. Lamp 6BFK will also be steadily lighted by a similar circuit controlled by relay 4BP. With relay 4BP deenergized, its contact 38 will be open in the normal pickup circuit previously traced for relays SFR and 6FR, but relays 5FR and 6FR will now remain energized by a normal stick circuit passing from terminal 1B, through contact 44 of relay 4BP, contact 45 of relay 6FR closed in the normal position, contact 46 of relay 6FR, windings of relays SFR and 6FR in multiple with a resistor t, and contact 47 of relay 6FR closed in the normal position, to terminal 1N.

Lamps SNK and 6NK will therefore remain lighted while lamps SBFK and 6BFK are steadily lighted. With lamps 6BFK and 6NK thus lighted, the leverman or dis patcher at the control station D will be informed that the leverman or dispatcher at control station A has controlled an east-bound signal to display a proceed indication for a traffic movement onto the stretch of track lld, or that the stretch of track a-d is occupied by an eastbound train.

If, now, the leverman or dispatcher at control station A should decide to stop the eastbound train at signal RA2, he will return lever 2V to the n position, thereby opening, at its contact 52, the circuit previously traced for mechanism RA2G of sginal RA2, and causing the signal mechanism to be returned to the stop position. When lever 2V reaches the n position, time element relay 2TB will become energized by a circuit passing from terminal B, through contacts y and g of signal RA2, contacts y and g of signal RB2, contact 9 of lever 2V, the back point of contact 10 of relay 2A8, and the winding of relay 2TE to terminal N. Upon the lapse of a measured period of time, relay 2TE will close its contact 12, thereby completing a pickup circuit for relay 2AS, this circuit passing from terminal B, through contacts y and g of signal RA2, contacts y and g of signal RB2, contact 9 of lever 2V, contact 12 of relay 2TB, and the winding of relay 2AS to terminal N. Relay 2AS, upon becoming energized by this pickup circuit, will again complete its stick circuit previously traced.

With relay 2AS again energized, relay 2ES will become energized by its pickup circuit previously traced, and will again complete its stick circuit, also previously traced. With relay 2ES again energized, its contact 32 will again complete the circuit previously traced for relays 2BP and 4BP.

-With relays 2BP and 4BP again energized, the circuits through the back points of contacts of these relays will be opened, thereby deenergizing indication lamps 5BFK and 6BFK. With relay 4BP again energized, the normal stick circuit traced for relays SFR and 6FR will be opened, but these relays will now again be energized by the normal pickup circuit previously traced for these relays.

With only indication lamps SNK and 6NK lighted, the leverman or dispatcher at each of the control stations A and D will know that the apparatus is now again in the normal condition.

If, instead of deciding to hold the eastbound train at signal RA2, the leverman or dispatcher at control station A, after controlling signal RA2 to display a proceed indication, permits the train to proceed onto the stretch of track ad and then, while the train is on section 1T, returns lever 2V to the n position, relay 2AS will become energized by a second pickup circuit which Is the same as the pickup circuit previously traced except that it includes contact 11 of relay lTR instead of contact 12 of relay 2TE.

Although relay 2AS is now again energized, relay 2E5 cannot become energized because contact 18 of relay lTR 18 open, and therefore contact 32 of relay 2ES remains open in the circuit for relays 2BP and 4BP, so that indication lamps SBFK and 6BFK will remain steadily lighted. When the train enters section 2T, relay 2TR will become deenergized, and therefore its contact 33 will open the circuit for relays 2BP and 4BP at another pomt.

When the train leaves section 1T, relay 2ES will become energized by its pickup circuit previously traced, and will therefore close its contact 32, but relays 2BP and 4BP will remain deenergized because contact 33 of relay 2TR is open.

If a leverman or a dispatcher at station D should inadvertently attempt to arrange for a' westbound train to enter the stretch a-d while a signal is controlled at station A for an eastbound train to enter this stretch, or while an eastbound train occupies the stretch between points a' and 0, he will move lever 6FV to its r position.

Relay 6FP will then become energized by a reverse control circuit passing from terminal 1B, through contact 29 of lever 6FV, and reverse control winding 30 of relay 6FP to terminal 1N.

' With relay 6FP thus energized by current of reverse polarity, its

contacts

36 and 40 will be moved to the reverse position out of correspondence with

contacts

37 and 39 of relay 4BP, thereby opening the normal pickup circuit previously traced for relays SFR and 6FR through these contacts. This will have no effect upon the energization of relays'SFR and 6FR, however, since contact 38.0f relay 4BP is already. open in 'thiscirciiit, and the normal stick circuit for relays SFR and 6FR is closed through. the back .pointof contact 44 of relay 4BP. Relays SFR and 61 R will therefore remain energized .by current of normal polarity, and with relays 23F and 4131 still deenergized; indication lamps SBFK and 6BFK will remain steadily lighted. With relays SFR and 6FRstill energized by current of..norrnal polarity, normal indication lamps SNK and 6NK will also remain lighted.

The leverman or dispatcher at control station D will be. thereby informed that a westbound tralfic movement onto the stretch of track a d cannot be authorized at this time because. a signal has been controlled to display a proceed indication ror an eastbound traific movement, or because an eastbound train already occupies this stretch of track. He will therefore return lever 6FV to the n position, and. will either hold the eastbound train atsig'nal R4 or will control signal R4 to display a proceed indication for authorizing the trainto continue in the eastward direction. The control of signal R4 is not a part of my invention, and is therefore not shown in fhe drawings.

If the leverman or dispatcher at control stationD controls signal R4 to display a proceed indication and the train accordingly continues its eastbound movement, relay 4AS will continue energized by its stick circuit. The pickup circuit for relay 4WS will be opened at contact 21 of .relay 3TR when the train enters section 3T, but relay.4WS will remain energized by its stick circuit previously described. When the train leaves section 2T, relays ZBP and 4BP will again be energized by thenormal control circuit previously traced. With relay 4BP again energized, relays SFR and GFR will again be energized bythe normal pickup circuit previously traced for these relays, and the normal stick circuit traced for these relays will again be pen- I,shall now assume that all parts of the apparatus are again in theno'rmal condition, and that the leverman or dispatcher at control station .D wishes to authorize a westbound train to enter the stretch of main track a-'d. He will, therefore, move traffic lever 6FV to its r position, and will thereby again complete the reverse ener? gizing circuit for relay 6FP.

Contacts

36 and 40 of relay 6EP will therefore be moved out of correspondence with

contacts

37 and 39 of relay 4BP, causingrelays 5BR and GFR to be deenergized. Since relay 4BP is now energized, its back contact 44 isv open in the normal stick circuit previously traced for relays. SFR and 6FR. With relay SFR deenergized, a circuit will becompleted for controlling indication lamp SBFK to display a flashing light indication, this circuit passing from terminalEB, through contact 58 of flasher relay SFL, contact 59 of relay SFR, contact 60 of relay SFR closed in the normal position, contact 61 of relay SFP closed. in

the normal position, front point of contact 62 of relay ZBP, and lamp SBFK to terminal EN. Lamp 6BFK will also be controlled by a similar circuit to display a flashing light indication. With. indication lamp SBFK displaying a flashing light indication, the leverman or dispatcher at control station A will be informed that the levermanor dispatcher at control station D Wishes to arrange for a westbound train to proceed over the stretch of track ad.

If the conditions at control station A are suitable for such a movement, the leverman or dispatcher at control station A will then move his lever SFV to the 7 position, thereby completing a reverse energizing circuit for relay 5FP which is similar to thereverse energizing circuit previously traced for relay 6FP. With relay SFP energized by its reverseenergizing circuit, contacts '31 and 35 of relay SFP will be moved to the reverse position, so that relays ZBP and 4BP will be energized by a circuit which is similar to the circuit previously traced for these relays except that it includes the contacts 31 and 35 of relay SFP in their reverse position instead of in the normal position.

Relay 4BP will therefore be energized by current of reverse polarity, so that its reverse contacts will be closed in correspondence with the reverse contacts of relay 6FP. Relays SFR and GFR will therefore now be energized by current of reverse polarity passing from terminal 1B, through contact 36 of relay 6FP closed in thereverse positiom. contacts .41 and not relay. 4BP', windings of relays SFR and 6FR in multiple with each other and 8 with .a resistor. I, contact 43 of relay 4BP, and contact 40 of relay 6FP closed in the reverse position, to terminal 1N. With relays SFR and 6FR again energized, contacts 59 and .64, respectively, of these relays will again be opened, causing indication lamps SBFK and 6BFK to become extinguished.

With relays :BR and 61 R energized by current of reverse polarity, the polar contacts 49 and 51, respectively, of these relays will be opened in the normal position and become closed in .the reverse position, thereby extinguishing lamps SNK and eNK. Lamp SRK will now be energized by a circuit passing from terminal EB, through contact 48 of relay .SFR, contact 49 of relay SFR closed in the reverse position, and lamp SRK to terminal EN. Lamp oRK .will also be energized by a similar circuit. With lamps SNK and 6NK extinguished and lamps SRK and GRK lighted, the leverman or dispatcher at each of the control stations A and D will know that the traffic locking apparatus is now in condition for a westbound train to move over the stretch 'of track ad.

The leverman or dispatcher at control station D will then move lever 4V to its f position, thereby opening its contact '13 and deenergiz'ing relay 4AS. When lever 4V reaches the 1 position, a circuit will be completed for energizing mechanism LA4G, this circuit passing from terminal 113, through contact 55 of lever 4V,

contacts

56 and 57 of relay 'GFR, contact 311w of switch 3, and mechanism LA4G 'to terminal 1N. Mechanism LA4G will therefore be moved to an approach proceed position, causing its contact y to become opened. With relay 4A8 deenergized, its contact 20 will open the circuit for relay 4W5, causing relay 4 WS to be deenergized.

With relay 4W8 deenergized, its contact 34 will open the reverse control circuit for relay 4BP, causing relays 2BP.and 4BP to he deenergized. The reverse pickup circuits for relays SFR and 6FR will now be opened at contact 41 of relay 4BP, but these relays will remain energized by the reverse stick circuit passing from terminal 113, through contact 44 of relay 4BP, contact 47 of relay 61 R closed in the reverse position, windings of relays SP5. and 6H? in multiple with each other and with a resistor 1, Contact 46 of relay 61 R, and contact 45 of relay 6FR in the reverse position, to terminal 1N.

With relays ZBP and 48? deenergized, lamps SBFK and '6BFK will be steadily lighted, by the circuits previously described through the back points of contacts 62 and 67, respectively, of these relays. With relays SFR and GFR still energized, by their reverse stick circuit, lamps SRK and 6RK will'remain energized. The leverman or dispatcher at control station A will therefore be informed that the leverman or dispatcher at control station D has controlled a signal to display a proceed indication fora westbound train to'enter the stretch azl, or that the westbound train has already entered, and occupies, this stretch. The'operationof the apparatus as the westbound train proceeds will'then be similar to the operation of the apparatus previously described for an eastbound train.

I shall next assume *thanafter the westbound train has left the stretch of track a-"d, the leverman or dispatcher at control station A desires to authorize an eastbound train to'moveover section a'-d. He will therefore return lever 'SFV to its n position. Relay SFP will then again be energized by its normal control circuit, causing its contacts'31'and'35 tobe-mov'ed to the normal position. Relay'dBP willtherefore again become energized by current of normalpolarity.

With relay 4BP energized by current of normal polarity, its polar contacts will be moved out of correspondence with the polar contacts of relay 6FP, causing relays SFR and GFR to bedeenergized. Indication lamps SBFK and GEEK will therefore again display'a flashing indication as'previously described, except that their circuits will include reverse contactsof the PP and FR relays instead of'normal contactsof these'relays, and lamps SRK and 6RK will'be extinguished. With lamp-GBFK displaying a flashing indication, the leverman or dispatcher at control station 'D will be informed that the leverman or dispatcher at control station A wishes to arrange for an eastbound trafiic'movement over the stretch of track ad.

If conditions are suitable at control station D, the leverman ordispatcher atcontrol station D will return lever GFV to its 11 position, and relaysSFR and 6FR will thena'gaih become energized by current of' normal polarity. Indication'la'mps "SBFK aridfiBFK will therefore be extinguished, and lamps SNK and 6NK will again be lighted as previously described. The leverman or dis patcher at control station A will thus be informed that the tralfic locking apparatus is in condition. for him. to control an eastbound signal to display a proceed indication for an eastbound train to move onto the stretch of track a-d.

I have described the operation of the apparatus embodying my invention as shown in the accompanying drawings, for a few typical trafiic movements, and it is believed that in view of such description taken with the accompanying drawings, the operation of the apparatus for any other possible traffic movement can be readily traced without further detailed description.

Although I have herein shown and described only one form of apparatus embodying my invention, it ,is-understood that various changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

1. In railway traffic controlling apparatus for a stretch of railway track which is provided with a first signal adjacent a given or first end of said stretch for governing traific movements in a given direction onto said stretch and with a second signal adjacent the opposite or second end of said stretch for governing traffic movements in the opposite direction onto said stretch, including a first control station for said first end of said stretch and a second control station for said second end of said stretch, and including a first trafiic control device and a first signal control device for said first control station and a second traffic control device and a second signal control device for said second control station, each of said control devices manually operable to a normal and a reverse condition, the combination comprising, a neutral block indication relay and a first polarized traific control relay for said first control station, a polarized block indication relay and a second polarized trafiic control relay for said second control station, a first contact controlled in conjunction with said first signal to be closed only while said first signal is controlled to display a stop indication, a second contact controlled in conjunction with said second signal to be closed only while said second signal is controlled to dispay a stop indication, a trafiic responsive contact normaly closed but becoming opened in response to cocupancy of said stretch of track by a train, means including said first and second contacts and said traific responsive contact and also including normal and reverse pole changing contacts controlled by said first manually operable traific control device for energizing said polarized block indication relay by current of normal or reverse polarity in series with said neutral block indication relay, means controlled by a front neutral and a normal polar contact of said polarized block indication relay and by a normal contact of said second traffic control device or by a front and a reverse polar contact of said polarized block indication relay and by a reverse contact of said second tralfic control device for energizing said traffic. control relays by current of normal or reverse polarity respectively, means including a reverse contact of said first signal control device and a normal polar contact of said first trafiic control relay for controlling said first signal to display a proceed indication, means including a reverse contact of said second signal control device and a reverse polar contact of said second traific control relay for controlling said second signal to display a proceed indication,

and indication means controlled by said block indication relays and by said tralfic control relays and also by said ,trafiic control devices.

2. In railway tralfic controlling apparatus for a stretch of railway track which is provided with a first and a second signal adjacent a given or first end and the opposite or second end respectively of said stretch of railway track for governing trafiic movements in opposite directions onto said stretch of track, including a first and a second control station for said first and second ends respectively of said stretch of track, and including a first trafiic control device and a first signal control device for said first control station and a second traffic control device and a second signal control device for said second control station, each of saidcontrol devices manually operable to a normal and a reverse condition, the combination comprising, a first polarized traffic control relay for said are control station, a polarized block indication relay and in. conjunction with said signalsv to be; closed only while said signals are controlled to display a stop indication, a traflic responsive contact normally closed but becoming opened in response to occupancy of said stretch of track by a train, means. including said trafiic. lockingcontact means and said traffic. responsive contact and also pole changing contacts controlled by said first traffic control device for energizing said polarized block indication. relay by current of normal or reverse polarity, means controlled by av front neutral: contact of said block indication relay and by normal and reverse polar contacts of said block indication. relay in correspondence; with normal and reverse contacts: respectively of said second traffic control; device for energizing said trafiic control relays by current of normal or reverse polarity respectively, means. including a reverse contact of said first signal control device and a normal polar contact of said first tralfic control relay for controlling said first signal to display a proceed indication, and means including a reverse contact of said second signal control device and a reverse polar contact: of said second traffic control relay for controlling said second signal to. display a proceed indication.

3. In combination, a stretch of railway track, a first and a second signal adjacent the. opposite ends of said stretch of railway track for governing trafiic movements in opposite directions. onto said stretch of track, a first and a second control station for said stretch of railway track, normal and reverse manually controllable traffic control contacts and a reverse manually controllable signal control contact for each of said control stations, a first polarized .traffic control relay for said first control station, a polarized block indication relay and a second polarized traffic control relay for said second control station, trafiic locking contact means closed only if said signal control contacts are. open, traffic responsive contact means normally closed but becoming opened in response to occupancy of said stretch of track by a train, means including said trafiic locking contact means and said trafiic responsive contact means and also said normal and reverse traffic control contacts for said first control station for energizing said polarized block indication relay by current of normal and reverse polarity respectively, means controlled by a front neutral contact of 'said block indication relay and by normal and reverse polar contacts of said block indication relay in correspondence with said normal and reverse tratfic control contacts respectively for said second control station for energizing said trafiic control relays by current of normal and reverse polarity respectively, means controlled by said signal control contact for said first control station and by a normal polar contact of said first polarized traffic con trol relay for controlling said first signal to display a proceed indication, and means controlled by said signal control contact for said second control station and by a reverse polar contact of said second polarized traffic control relay for controlling said second signal to display a proceed indication.

4. In combination, a stretch of railway track, a first and a second signal adjacent the opposite ends of said stretch of railway track for governing traffic movements in opposite directions onto said stretch of track, normal and reverse manually controllable traffic control contacts and a manually controllable signal control contact for each end of said stretch of track, a first polarized traffic control relay for a given or first end of said stretch of track, a polarized block indication relay and a second polarized trafiic control relay for the opposite or second end of said stretch of track, trafiic locking contact means 'closedonly if said signal control contacts are open, traffic responsive contact means normally closed but becoming opened in response to occupancy of said stretch of track by a train, means including said traffic locking contact means and said trafiic responsive contact means and also said normal and reverse traffic control contacts for said first end of said stretch of track for energizing said polarized block indication relay by current of normal and reverse polarity respectively, means controlled by a front neutral contact of said block indication relay and by normal and reverse polar contacts of said block indication relay in correspondence with said normal and reverse traffic control contacts respectively for said second end of said stretch of track for energizing said trafiic control relays by current of normal and reverse polarity respectively, means controlled by said signal control contact for said first end of said stretch and by a normal polar contact of said first polarized trafiic control relay for controlling said first signal to display a proceed indication, and means controlled by said signal control contact for said second end of said stretch and by a reverse polar contact of said second polarized trai'fic control relay for controlling said second signal to display a proceed indication.

5. In combination, a stretch of railway track, a first and a second signal adjacent the opposite ends of said stretch of railway track for governing trafiic movements in opposite directions onto said stretch of track, normal and reverse manually controllable traffic control contacts and a manually controllable signal control contact for each end of said stretch of track, a first polarized traffic control relay for a given or first end of said stretch of track, a polarized block indication relay and a second polarized trafiic control relay for the opposite or second end of said stretch of track, traffic locking contact means controlled in conjunction with said signals to be closed only if said signals are controlled to indicate stop, means including said trafiic locking contact means and said normal and reverse traffic control contacts for said first end of said stretch of track for energizing said block indication relay by current of normal and reverse polarity respectively, means controlled by a front neutral contact of said block indication relay and by normal and reverse polar contacts of said block indication relay in correspondence with said normal and reverse trafiic control contacts respectively for said second end of said stretch of track for energizing said trafiic control relays by current of normal and reverse polarity respectively, means controlled by said signal control contact for said first end of said stretch and by a normal polar contact of said first trafiic control relay for controlling said first signal to display a proceed indication, and means controlled by said signal control contact for said second end of said stretch and by a reverse polar contact of said second trafiic control relay for controlling said second signal to display a proceed indication.

In combination, a stretch of railway track, a first and a second signal adjacent the opposite ends of said stretch of railway track for governing trafiic movements in opposite directions onto said stretch of track, normal and reverse manually controllable traffic control contacts and a manually controllable signal control contact for each end of said stretch of track, a first polarized trafiic control relay for a given or first end of said stretch of track, a polarized block indication relay and a second polarized trafiic control relay for the opposite or second end of said stretch of track, trafiic responsive contact means normally closedbut becoming opened in response to occupancy of said stretch of track by a train, means including said trafiic responsive contact means and said normal and reverse trafiic control contacts for said first end of said stretch of track for energizing said block indication relay by current of normal and reverse polarity respectively, means controlled by a front neutral contact of said block indication relay and by normal and reverse polar contacts of said block indication relay in correspondence with said normal and reverse tratfic control contacts respectively for said second end of said stretch of track for energizing said traffic control relays by current of normal and reverse polarity respectively, means controlled by said signal control contact for said first end of said stretch and by a normal polar contact of said first trafiic control relay for controlling said first signal to display a proceed indication, and means controlled by said signal control contact for said second end of said stretch and by a reverse polar contact of said second trafiic control relay for controlling said second signal to display a proceed indication.

7. In combination, .a stretch of railway track, a first and a second signal adjacent the opposite ends of said stretch of railway track for governing traific movements in opposite directions onto said stretch of track, normal and reverse manually controllable trafiic control contacts and a manually controllable signal control contact for each end of said stretch of track, a first polarized trafiic control relay for a given or first end of said stretch of track, a polarized bloclg indication relay and a second polarized traffic control relay for the opposite or second end of said stretch of track, traffic responsive contact means normally closed but becoming opened in response to occupancy of said stretch of track by a train, means including said trafiic responsive contact means and said normal and reverse trafiic control contacts for said first end of said stretch of track for energizing said block indi-' cation relay by current of normal and reverse polarity respectively, means controlled by a front neutral contact of said block indication relay and by normal and reverse polar contacts of said block indication relay in correspondence with said normal and reverse trafiic control contacts respectively for said second end of said stretch of track for energizing said traffic control relays by current of normal and reverse polarity respectively, means controlled by said signal control contact for said first end of said stretch and by a normal polar contact of said first traffic control relay for controlling said first signal to display a proceed indication, means controlled by said signal control contact for said second end of said stretch and by a reverse polar contact of said second trafiic control relay for controlling said second signal to display a proceed indication, and retaining circuit means for said trafiic control relays including a back contact of said block indication relay in series with a front neutral contact and a normal or a reverse polar contact of said second trafiic control relay.

8. In combination, a stretch of railway track, a first and a second signal adjacent the opposite ends of said stretch of railway track for governing tralfic movements in opposite directions onto said stretch of track, normal and reverse manually controllable trafiic control contacts and a manually controllable signal control contact for each end of said stretch of track, a first polarized trafiic control relay for a given or first end of said stretch of track, a polarized block indication relay and a second polarized tratfic control relay for the opposite or second end of said stretch of track, traffic locking contact means controlled in conjunction with said signals to be closed only if said signals are controlled to indicate stop, means including said traffic locking contact means and said normal and reverse tratfic control contacts for said first end of said stretch of track for energizing said block indication relay by current of normal and reverse polarity respectively, means controlled by a front neutral contact of said block indication relay and by normal and reverse polar contacts of said block indication relay in correspondence with said normal and reverse traific control contacts respectively for said second end of said stretch of track for energizing said traific control relays by current of normal and reverse polarity respectively, means controlled by said signal control contact for said first end of said stretch and by a normal polar contact of said first traffic control relay for controlling said first signal to display a proceed indication, means controlled by said signal control contact for said second end of said stretch and by a reverse polar contact of said second traffic control relay for controlling said second signal to display a proceed indication, and retaining circuit means for said traffic control relays including a back contact of said block indication relay in series with a front neutral contact and a normal or a reverse polar contact of said second trafiic control relay.

9. In combination, a stretch of railway track, a first and a second signal adjacent the opposite ends of said stretch of railway track for governing trafiic movements in opposite directions onto said stretch of track, trafiic control means for each end of said stretch of track each manually operable to a normal and a reverse condition, a polarized block indication relay, trafiic locking contact means controlled in conjunction with said signals to be closed only if said signals are controlled to display the stop indication, traffic responsive contact means normally closed but becoming opened in response to occupancy of said stretch of track by a train, block indication circuit means including said trafiic locking contact means and said trafiic responsive contact means and controlled by said traffic control means for a given or first end of said stretch of track for energizing said block indication relay by current of normal and reverse polarity, means for effecting operation of said signal for said first end of said stretch for displaying a proceed indication controlled by means including a front neutral contact and a normal polar contact of said block indication relay and said trafiic control means for said second end of said stretch in its normal condition, and means for eifecting operation of said signal for said second end of said stretch for displaying a proceed indication controlled by means including a front neutral contact and a reverse polar contact of said block indication relay and said traflic control means for said second end of said stretch in its reverse condition.

10. In combination, a stretch of railway track, a first and a second signal adjacent the opposite ends of said stretch of railway track for governing trafiic movements in opposite directions onto said stretch of track, trafiic control means for each end of said stretch of track each manually operable to a normal and a reverse condition, a polarized block indication relay, traflic locking contact means controlled in conjunction with said signals to be closed only if said signals are controlled to display the stop indication, trafiic responsive contact means normally closed but becoming opening in response to occupancy of said stretch of track by a train, block indication circuit means including said trafiic locking contact means and said traflic responsive contact means and controlled by said trafiic control means for a given or first end of said stretch of track for energizing said block indication relay by current of normal and reverse polarity, a first and a second polarized traflic control relay for said first end of said stretch and the opposite or second end of said stretch respectively, means including a front neutral contact of said block indication relay and a normal or a reverse polar contact of said block indication relay in series with a normal or a reverse contact respectively controlled by the trafiic control means for said second end of said stretch for energizing said traffic control relays by current of normal or reverse polarity respectively, retaining circuit means for said traffic control relays including a back contact of said block indication relay in series With a front neutral contact and a normal or a reverse polar contact of said second trafiic control relay, means including a normal polar contact of said first trafiic control relay for controlling said first signal to display a proceed indication, and means including a reverse polar contact of said second traffic control relay for controlling said second signal to display a proceed indication.

11. In combination, a stretch of railway track, a first signal adjacent a given or first end of said stretch and a second signal adjacent the opposite or second end of said stretch for governing traffic movements in opposite directions onto said stretch, first and second trafiic control means for said first and second ends respectively of said stretch each manually operable to a normal and a reverse condition, traflic locking contact means controlled in conjunction with said signals to be closed only While said signals are controlled to display a stop indication, traffic responsive contact means normally closed but becoming opened in response to occupancy of said stretch of track by a train, a neutral block indication relay, a polarized block indication relay, block indication circuit means including said traffic locking contact means and said traffic responsive contact means and controlled by said first traific control means for energizing said polarized block indication relay by current of normal and reverse polarity in series with said neutral block indication relay, a first and a second polarized traffic control relay for said first and second ends respectively of said stretch, normal and reverse control circuits for said trafiic control relays controlled by normal and reverse contacts respectively of said polarized block indication relay and said second trafiic control means and also controlled by a front neutral contact of said polarized block indication relay, traific indication control circuit means for each end of said stretch each including normal and reverse polar contacts of the corresponding traffic control relay in series with normal and reverse contacts respectively of the corresponding traffic control means and also controlled by a back contact of the corresponding trafiic control relay and by a front contact of the corresponding block indication relay, other indication control circuit means for each end of said stretch each controlled by a back contact of the corresponding block indication relay, still other indication control circuit means for each end of said stretch each controlled by front and polar contacts of the corresponding trafiic control relay, means including a normal polar contact of said first trafiic control relay for controlling said first signal, and means including a reverse polar contact of said second tratfic relay for controlling said second signal.

12. In combination, a stretch of railway track, a first signal adjacent a given or first end of said stretch and a second signal adjacent the opposite or second end of said stretch for governing traflic movements in opposite directions onto said stretch, first and second trafiic control means for said first and second ends respectively of said stretch each manually operable to a normal and a reverse condition, traffic locking contact means controlled in conjunction with said signals to be closed only while said signals are controlled to display a stop indication, trafiic responsive contact means normally closed but becoming opened in response to occupancy of said stretch of track by a train, a neutral block indication relay, a polarized block indication relay, block indication circuit means including said trafiic locking contact means and said tratfic responsive contact means and controlled by said first traflic control means for energizing said polarized block indication relay by current of normal and reverse polarity in series with said neutral block indication relay, a first and a second polarized traffic control relay for said first and second ends respectively of said stretch, normal and reverse control circuits for said trafiic control relays controlled by normal and reverse contacts respectively of said polarized block indication relay and said second trafiic control means and also controlled by a front neutral contact of said polarized block indication relay, traific indication control circuit means for each end of said stretch each including normal and reverse polar contacts of the corresponding trafiic control relay in series with normal and reverse contacts respectively of the corresponding trafiic control means and also controlled by a back contact of the corresponding traffic control relay and by a front contact of the corresponding block indication relay, means including a normal polar contact of said first trafiic control relay for controlling said first signal, and means including a reverse polar contact of said second trafiic relay for controlling said second signal.

13. In combination, a stretch of railway track, a first signal adjacent a given or first end of said stretch and a second signal adjacent the opposite or second end of said stretch for governing traffic movements in opposite directions onto said stretch, first and second trafiic control means for said first and second ends respectively of said stretch each manually operable to a normal and a reverse condition, tratfic locking contact means controlled in conjunction With said signals to be closed only while said signals are controlled to display a stop indication, traflic responsive contact means normally closed but becoming opened in response to occupancy of said stretch of track by a train, a polarized block indication relay, block indication circuit means including said trafiic locking contact means and said trafiic responsive contact means and controlled by said first traflic control means for energizing said block indication relay by current of normal and reverse polarity, a first and a second polarized traific relay for said first and second ends respectively of said stretch, normal and reverse control circuits for said traffic relays controlled by normal and reverse contacts respectively of said block indication relay and said second trafiic control means and also controlled by a front neutral contact of said block indication relay, means including a normal polar contact of said first traific relay for controlling said first signal, and means including a reverse polar contact of said second trafiic relay for controlling said second signal.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 2,271,510 Allen Feb. 3, 1942 2,354,023 Ihrig July 18, 1944 2,586,458 Failor Feb. 19, 1952