US2095044A - Railway traffic controlling apparatus - Google Patents

Description

Oct. 5, 1937. H. c. vANTAssEL RAILWAY TRAFFIC CONTROLLING APPARATUS Y INVENTOR yC. Vanzssel.

Filed OCQ. 18, 1935 g2 HIS ATTORNEY 'Ocf- 5, 1937 H. c.' vANTAs'sx-:L

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed oct. 18.` .1955

2 sheets-she# 2 -HIS ATTORNEY Patented Oct. 5, 1937 UNITED STATES RAILWAY TRAFFIC CONTROLLING APPARATUS Harry C. Vantassel, Swissvale, Pa., assignor to The Union Switch & Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application October 18, 1935, Serial No. 45,612

14 Claims. f (Cl. 246-134) My invention relates to railway traic controlling apparatus, and more particularly to apparatus which will give maximum protection to traiiic movements over non-track circuited sections of a track layout.

The apparatus of my invention is an improvement over that disclosed in the copending applications Serial No. 125,659, led July 29, 1926, by Herbert A. Wallace for Railway traic controlling apparatus; Serial No. 313,772, filed October 20, 1928, by Howard A. Thompson for Multiple `control apparatus; and Serial No. 416,061, led December 23, 1929, by Howard A; Thompson for Multiple control apparatus.

In the accompanying drawings, Figs. 1 and 2 are y diagrammatic views showing alternative forms of circuits and apparatus, each embodying my invention.

Similar reference characters refer to similar parts in each of the views.

Referring rst to Fig. 1, the reference characters la and lb designate the rails of a stretch of railway track designated Y, the rails of which are divided by insulated joints 2 to form track sections T, IT, and 3T, respectively. Each track section is provided with the usual track circuit including a track battery 3 and a track relay designated R with a prefix designating the section to which it belongs. A siding Z is connected with section 3T through the medium of a switch designated W3. Y

The stretch of track Y is provided for normal traic movements from left to right, while a similar stretch of track X is provided for normal traic movements from right to left, a crossover having associated switches WI and Wla being provided to permit trame movements between tracks X and Y. Signals L4A and L4B are provided for directing traic movements toward the leit over switch Wl'a in its normal position and over switches Wla and WI in their reverse position, respectively; while signals R2A and R2B are provided for directing traflic movements toward the right over switch WI in its normal position and over switches WI and WI a in their reverse positions, respectively. The slow speed signals LtA, LtB, and L2 are provided for directing traine movements toward the left over switch W3 normal, switch W3 reversed and over switch WI normal, respectively. The slow speed signal R4 is providedfor directing traffic movements toward the right over switch Wla normal. The stretch of track X is provided with two track circuited sections AIT and A2T, respectively. The portion of the crossover between sections IT and AIT includes a non-track circuited section U, and therefore other means, as will appear hereinafter, is provided to provide protection for traic movements between tracks X and Y.

'The movement of traffic over tracks X, Y, and

Z is under the control of an operator and is effected by means of the interlocked signal control levers V2 and Vt and the switch control levers VI and V9. These levers are of a type commonly employed in power interlocking practice and each is provided with an electric lock controlled by a lock magnet M identied by a numerical suiiix corresponding to the lever it controls. In addition, track repeating stick relays ITPS and AITPS, and route locking relays IES and IWS are provided for controlling the lever locking. A local source of direct current is provided for energizing the various relays and magnets, but to simplify the drawings, only the terminals of the source have been shown, these bearing the references B and C to designate the supply and common return terminals, respectively, of the source. Relay lTPS is normally energized and has a pick-up` circuit which may be traced from terminal B of the local source of current, front ycontact il of the track relay ITR, relay ITPS, front contact l2 of relay IWS, contact NL of lever V2, to the other terminal C of the source. A stick circuit for relay ITPS is also closed, and may be traced from terminal B, contact II of relay ITR,

'the winding and front contact 32 of relay ITPS to terminal C.

Relay AITPS is normally energized, and has a pick-up circuit which may be traced from terminal B over front contact I3 of the track relay AITR, relay AI'I'PS, front contact I4 of relay IES in multiple with normally closed contact N332 of switch lever VI contact NR of signal lever Vt to terminal C. A stick circuit for relay AITPS is also closed, and may be traced from terminal B, contact I3 of relay AITR, the winding and front contact i2 oi relay AITPS to terminal C. Route locking relay IES has a pick-up circuit which may be traced from terminal B, contact Ld of signal lever V2, front contact I5 of relay ITPS, contact NI of lever VI and back contact 35 of relay AITPS in multiple, relay IES to terminal .C. Relay IES is normally energized over its stick circuit, which may be traced from terminal B, contact Ld cf lever V2, front contact Iii and winding of relay` EES to terminal C. Relay ViWS hasy a lpick-up circuit which may be traced from terminal B over contacts Rb of lever V4 and N323 or lever Vi in multiple, contact 3l of relay AiTPS, back contact 33 of relay ITPS, relay I WS to terminal C. Relay IWS is normally energized lover its stick circuit, which may be traced from terminal B over contacts Rb of lever V4 and Nm3 of lever VI, in, multiple, front contact 41 and winding of relay iWS to terminal C.

The signal lever lock magnets M2 and M4 are held energized over circuits including contact 4 of the track relay TR and 5 of the track relay AZTR, respectively, as is obvious from the drawings, so that their locking dogs I'I and I8 are held Y VY50 f contacts ofjthe signal'lever used'in the control i f' Yoftengagement with theirr'locki'ng segmentsV f I9V and 20, respectively.' These levers Aare there'- 1'0 Y Y 4 traced from'terminal B, front contact'25 of relay Y Vfore normally free'to be moved by the operator. VThe switch lever lock-magnetsY MI and M3are also 'energized,Y so that their respective locking dogs 2I and 22 are held out oiv engagement Ywith the notchesof'their respective segments 23V and 24; 'The switchcontrol'levers VI. and V3 are ac-V cordingly alsognormally'fr'ee to be Ymoved by the operator- The circuit formagnet MI may be IWS, front contact'26 of relay I TPS,'back contact 36 of Va. time element mechanism A4'I'E, magnet v MI, backV contact 3I `of asecond timeelement f VVmechanism A2TE, front. contact-[2lv of s relay AYIT'PS, frontcontactZ of relay IES, to terminal C.V Thercircuit Vfor magnet M3 mayV be .traced 'Y from terminal kB', frontfcontacts 29 and 30 of 40"and-381w hich Ymay be closedjat times'to bridge Y 'relays` STR and IES,"respectively, magnet M3, to

terminal C. The 'timer elementmechanismAZTE is provided with av'pairof normally open contacts contact/s4 and,35 inthe circuitsforrma'gnet M2 Y* Yand 'relayjfIES respectively, f Timef'elementmechanism A4TE Yhas similar contacts 4I and 39j Y which may beV closed at times tobridge contacts Sand 33 in thecircuits'formagnet M4 and relay IW S, respectively. Y

' Vploye'd 'has no bearing on the present invention,YY

`nonef'of ther-signal'cir'cuits have been shown.'v it 'is believed sufficient toQexplainjthat, asV in ordi-VV Vnarypractice, when signal lever V2 jis moved Yto.` Y 1 its R'positiomsignal RZA or RZB will be cleared dependingron Vwhether switches WI and WIa are WIVV and WIa and switch machine SM3 @for .con-VVV TheV circuits employedV inV theV control of. theV several' signals shown may comprise anyone ofVY several wellknown arrangements, but since the particular arrangement of ,signalrcircuits emf in'thernormal or reversezposition', respectively,

.and that/'signal'LZ will be cleared when switches W I 'and' WIor are in their .normal position Vand- Ylever V2Vis moved to the Lposition. In a similar l manner, when signal'lever V4 is moved to its R Vposition and switches WI andV Wla. are intheir Vnormal position, signal R4.,will` becleared, and

s'ignal"L4A"orV LB will 4be `cleared'when signal lever V4isrmovedrtogits1i position, depending on whether switches WIfandfrWIa are in thegnorm'al or reverse position',respectively.` VAs none fof the circuits embodied in the present'invention'employ of signals LBA and LGB, the'leverforrcontrolling Vthese signals has notV been shown.

` VVAs'thejcirc'zuits vemployed to control switch machines VSMI and SMIa for controlling Yswitches Y' Vvtrolling','switchW3 Vform Vno Vpart of the present invention, they have Valso been omitted from the drawings. YIt is believed suflicient to explain that when switch control leverVI is moved toposition Y o, N, Yasc shown, the switchmachines SMI and'SMlI'a will be operated to move their'switches'to the'V normalvposition', and that similarly when lever, VI Vis moved-to position R, itwill be eie'ctive lto VcauseY the Yswitch ma'clfiinesY VtoV move'switches WI and WIa', to their reverse position. In asimilar manner, movement of lever V3 controls the Voperation of switch machine SMB Ito move switchrW3` to normal ortofreverse. Y io Itis believed 'that an Vunderstanding ofthein-V vention `canr'best'be obtained byY describing the Y various operations which occur, during the control of traiiic movements. For vthis purpose, it will first ,beassumedrthat switches WI and WI a ofw the crossover are in their normal position, as

Y shown, Vand that thegoperator moves signal lever' V2 toV the R position to clear signal RZA'to permit a traflic movement Vfrom left to rightvover trackl Y Y. Asle'ver`V V2" is moved Yfrom position Ngthe v1 pick-up circuit for relay ITPS is opened atcontact NL of lever V2, but relay II'PS'Y remains Y picked Yup, over its stick circuit. When lever'V2 "'is'movedlbe'yond position contact Ld opens the pick-up and stick circuits for relay IES.V Relay vIES accordingly releases, and its front Acontact I6 opens'a second pointY in its own stick circuit .`..k Y Y RelayV IES also, 'at front contactV I4, opens lonej i of the two multiple paths inthe--pick-up circuit Y for relay A ITPS, and at its front contact 28, opens' the circuit for lock magnet MI. Magnet MI ace-v cordingly releases vand drops itsV locking dogf2l into,.thewnormalnotch of; segment 23, therebyf 1ocking.,svvitcl'i"leverVIk against movement. Re-

lay YI ES likewise, atg` its `frontfcontact ,30,Yopens1. 20 f the circuit forlock magnet M3, which releases and drops its locking dog 22 into the normal notch of itsV segment 24, therebylocking switch control YIf now an approachingtrain enters section T,

lever VV2 beyond Yitsfindicfation position d. `In this position Vthe signal circuits are open,Y the signal leversbeing arranged inaccOrdanCeWith ment or the lever irom'itsj Rt'o its d position or i the usual practiceV so thata cleared signal may- ,beV V;

returned to its stop position manually by a movef ,ci y Y I fromA its L to its oposition, as'the case may be.

If now a'train accepts thefcleared signal R2A,

and enters sectiOnIT, track relay -I'IR releases f and, at back contact 34,.'closesV an obvious circuitjV forV magnet M2 Ywhich again picks up' and'lwith- .draws the locking dog'II from the notch Vin segment I9, enabling the operator to return lever VV2VA Y to its'norm'al position N. Relay ITR 1also,.at its I'IPS. Relay ITPS then'releases, its front,V conf Vtact32 opening a'second point in its stickY circuit, its front Contact l5 opening a second point inthe pick-up circuitfor relay IES', and its back 'contact 33 'closingra pointin Va pick-up circuit forrelay IWS. Front `Contact, 26 of relaycITPS openfsa second point in the circuit for lever lock magnet vfr'ont'conta'ct I l, opens'th'e stickV circuit for'relay MI thereby preventing movement of switches WI and'wlja through the medium Yof switch lever vlY l Y i ,While section IT is occupied. Switch lever V3 controlling-switch W3 Vremains locked because relay IES is still deenergized.

When the train enters section 3T, track relayV STR releases and,at front contact`29,;opens a second point in the circuit for rmagnet'M3, thereby preventingmovem-ent ofl switch W3Y while sectionV IT,'t'rack relay YI'IR" again picks'up, and e v assuming the operator'tofhavel restored @signal lever'VZto its normal positiomgat front contact 7' Y,

I I `again completesA the Vpick-up circuit Vjfor relay- I'I'PS.V When relay ITPS picksfup, its ffrontc'on-LY traced for relayIESQwhile its front contact26 4tact I5 completes the pick-upV circuit previously,

closes one of the twopoints opened in the circuit for magnet MI. `When relay IES picks up, Vits ToY front contact 28 completes the circuit for magi" Vnet ,MI which aocordinglypicks upto withdraw Relay locking dog 2I to unlock. switch lever VI.

IESalso, at front'contact 3U closes one of the Y two points openedvin the circuit Vfor magnet M3,

tion 3Tis1occupied. When the Ytrainvacates secso that this magnet can pick up to withdraw its locking dog 22 to unlock switch lever V3 as soon as the train vacates section 3T. It will therefore be seen that when signal R2A is cleared, relay IES functions as an ordinary route locking relay.

It will now be assumed that switch lever VI has been reversed and that accordingly switches WI and and WIa are in their reverse position, and that signal lever V2 is moved to its R position to clear signal R2B for a traffic movement from left to right from track Y to track X over the crossover. If now a train moves past signal R2B and enters section IT, track relay ITR releases and effects the release of relay ITPS. The circuit changes effected by the release of relay ITPS are the same as already described, magnet MI releasing to lock switch lever VI. Relay IES also releases and performs the same circuit changes as already described, except that, since lever VI is in its R position, its contact Ry in multiple with front contact 30 of relay IES is closed. Lock magnet M3 therefore remains energized and lever V3 is left free to be moved by the operator, this being permissible because the route which has been established does not include switch W3.

With lever VI in its R position, one branch of the pick-up circuit previously traced for relay AITPS will be open at contact N032 of lever VI and, on account of relay IES being deenergized, the other branch of this circuit will be open at contact I4 of relay IES. Relay AITPS will, however, remain energized over its stick circuit.

When the train vacates section IT, if the train is short enough to be wholly included within section U, track relay ITR will pick up before relay AI TR releases, and these relays will for a time fail to show the presence of the train on the crossover track. The switch locking however remains effective even though the operator has in the meantime restored signal lever V2 to position N, because relay IES will not pick up when relay ITPS picks up, as in the case of the movement over switch WI normal previously described due to the fact that the pick-up circuit for relay IES is now open at Contact NI of switch lever VI, this lever being now in its reverse position. `Relay IES will therefore remain released after the train vacates section IT, thus holding the circuit for lock magnet MI open at front Contact 28 while the train remains wholly within section U, and switches WI and WIa: therefore remain locked. When the train enters section AIT, track relay AITR releases and, at its front contact I3, opens the stick circuit for relay AITPS. When relay AITPS releases, its front contact 21 opens a second point in the circuit for magnet MI to prevent MI from picking up as long as section AIT remains occupied, and its back contact 35 which is in multiple with contact NxI completes the pick-up circuit for relay IES. When relay IES picks up, its front contact I4 closes to prepare a pick-up circuit for relay AITPS and its front contact 28 closes one point in the circuit for magnet MI. Front Contact I4 of relay IES is included in the pick-up circuit of relay AITPS in order to insure that even though relay AITR is deenergized but a short time due to the high Speed movement of a short motor car over the crossover, relay AITPS will remain deenergized until relay IES is picked When the train vacates section AIT, relay AITR again picks up and at front contact I3 closes the prepared pick-up circuit for relay AITPS. .Relay AITPS then picks up and at front contact 21 completes the circuit for magnet MI, which, in turn, picks up to withdraw its locking dog ZI to enable the operator to again move switch lever VI to effect movement of switches WI and WIa.

It will be observed that lock magnet M2 of signal lever V2 is energized as long as the approach section T is unoccupied and that therelfore free movement of the lever to any of its several positions is at such time possible. If the operator moves lever V2 to the R position to clear signal R2A or R2B and then attempts to return the lever to its N position after approach section T has become occupied, locking dog Il of magnet M2 will at the time be in engagement with a notch of its segment I9 and so will prevent the immediate restoration of lever V2 beyond position d. When contact Ld becomes closed, relay IES will pick up provided relay ITPS is energized and lever VI is normal, closing contact 28 to energize magnet MI. It is to be understood, however, that lever VI can be moved only when lever V2 is in position N owing to the f customary mechanical locking arrangement effective between levers V2 and VI and that lever VI is locked mechanically by lever 'V2 when V2 is in other than its N position. It will be evident,

therefore, that when signal RZA is put to stop 38 and 4I), its back contact 3l opens the circuit from terminal B, contacts Ld, I5 and 38, relay ,Y

IES to terminal C. Relay IES, therefore, picks up and at front contact 28 again closes a point in the circuit for magnet MI. The time element mechanism A2TE may now be restored to normal to close back contact 3'I to complete the circuit for magnet MI to unlock switch lever VI at the end of a predetermined time interval. In practice this time interval is made such that a train approaching in section T will either be brought to a stop before entering section IT, or if unable i to stop will enter section IT and cause contact 23 to yopen before contact 3l closes so as to maintain the locking effective until the train vacates section IT.

It will Vnext be assumed that a train accepts signal R2B and enters section IT, and that lever V2 is then restored to position N, but that the train does not enter section AIT but backs of section IT with a View to making a subsequent movement over track Y under the control of signal RZA. Relay IES having been released, magnet MI is deenergized to lock lever VI so that switches WI and WIal cannot be restored to normal. The locking may be released in this instance by Operation of the time release mechanism'AZVTE Vtorclosecontact 3.8VVV thereby energizing Y Y j relay IES torclose contact 28, andby then Yrestoring mechanism AZTE tojnormal to'close Contact 31 to'complete the circuit for magnet MI thereby vreleasing the locking ofv lever VI sogthat switches `WI and WIa may be restored to normal to per- Vmit signalRZA to be cleared to eifectithedesired Ytrain movement. rIt will Yberevident, therefore, Y thatV the apparatus of my invention providesV complete time locking protection againstY theA m'ove; ment of switches WI and WIa when aftrainY oc- Vcupies thernon-track circuited sectionvU'.

My apparatus can also be Yemployed to jadvantagerto protect Ytrainmovements over a crossover in "which section `IT adjoins section'AIT,

' .but which is so infrequently usedthat the crossover track may becom'e'heavily coated with rust (vso as to interfere vvwith theV proper shunting of*v the track circuitsbylight-'weight equipment; asV Y 270 vit willV be Yevident that relay IESwill'maintain f; Vthelocking.effective while'thertrain is uponthe crossover andfuntil itreaches the Vclean rails of 'theV` main YVtrack portion ofgs'ectionlAI'Irrto shuntY Vthet'rack'relay A'ITR. l

The route locking and time element lrelease 'ciri cuits -havingto do Withfa trafic'movement to the YV'left ,iro'mj track to: l trackv Y over the crossover f involve theoperationof'relays AITPS andY IWS and' time element mechanismalI'I'E and are sim'- ilar to Yandfunction in the samev manner as the corresponding'circuits f for Ythe ,opposite direction oneresult of clearing signal R2AV is to release relay'IEStolock switchlever V3jas already-pointed havingto do withV a corresponding;`traflio move- VAment tothe left overtrackV X are differently 'ar-v ranged. Thus route Ylocking relay IWS -is preventedfromjreleasing when lever V4 is moved to' the left teclear signal LA by reason of the connection from terminalBzover contact Nm3 when switch lever VIv is in vits normalposition, so that Y relayi IWS ,does not control'the locking 'circuits' Vfortracl: YV when switches YWI and W:Ia are nort- 0f relayV IWs wiirpe simuarto'that of relay InsV V-blV'Signal lever V2. f Y

mal. ',ItV will Vbe apparentfhowever that when switch lever'VI isin Vits reverse rposition and sigi.

nal lever VilVA has been moved to its L position to clear signal LGB Vfor a crossover move the control In Fig. 2 I have illustrated 'my inventionV appliedto the same track arrangement as employed in Fig. 1 and'involving thejsa'me` trackfrelays,Y jY

traclrepeating'relays,and Wayside signal equipment.Y The invention, as shown inFig. 2,y contemplates the remote control ,of the switches and signals either over-'1a Vdirect Wire system orV Y through the medium Yof anyone of; the e' well j YVknown centralized/traino controlY systems. In

this form ofY my invention'iremote controlled switch control relays IX and IY, 3X and SY-andY remote controlled signal control'relaysRZHS and vLiHS take the place .of the signal Vlevers employed inthe form Yof the invention illustrated in Fig. Y1, while approach locking relays IELS andV IWLS take'the `'place of .lever locking; Va'nd'emer- Vgency release relays; IER, ,and 2ER.',.and4T thermal Y ATTE. Y

place of the time element mechanisms A2TE and In Fig. 2, in4 order toVV prevent unduly complieating the Vdrawings,contactsof various ofthe relays employedl'ar in Vsortieinstances.not 'ad Y jacent their relay, but in each such -instance a reference character corresponding tothe relayV to'. which a'.V contact belongs isassociated ,withfl Y the contact in addition to thel usual reference numeral given to such contact.

"I'he control of switchesWI anclWl/Tlul and ,ofV Y switch W3 in Fig. 2 is effected by means of Vpolarized switch controlYV relays IWR andSWR..V 'I he Ynormal control circuit 'for Y relay IWR maybe traced from terminalV B, Contact 43 of `relay IWLS, contacts 25, 2 5, 21, and 28 of relays IWS,

BZTE,y respectively, back contact? 5 of reverse switch control relay. IX, front Contact] of "nor-1V mal switch controlk relay JY, relay 'IWR, frontY Y, contact A8 oirelay IY, back Contact 9'of relay yIX e to terminal C,"this circuit ,beingY completedwhenY relay IY; is energized andrelay IX is deenergized,

i to energize relay IWR in the normal direction.

The reverse control circuit forrelayfIWlR,` is'sirniil Y lan/but includes frontcontacts 6 and Sand back` VI'IPS, AI'IPS, and IES, respectively,V back 'con-lf tactM of the emergency release relay IER,-back contacts 66 and 51 of Y'thermal relays BATErandf relay IWR in the Vreversefdirection when'relay-1Xk Y isenergized and relay IY is deen-ergized;k Conl"tacts 25 to'23V arethe same' as Vthe contacts bearing the same references'in Figflf,v and Ycontacts `IS o andG'I correspond in function to ' contacts 35 and 31 in Fig. 1; and it follows Ythat relay IWR is dethese' contacts under conditions corresponding to the locking of lever VIiloy magnet MI in. Fig. 1, while Contact lItas will hereinafter appear,"opens to deenergize relay IWR under conditions corre-.-

Contact v44 is a .ch'eclr'fcontact which Vinsures that relay'IER isdeenergized beforeV the' locking is" released. Thelocal Vcircuits by -means energized Vbythe opening offene or 4another'of .spondingtothe: lockingoi VleverA VI Yby lever 'V2' in'Figl 1.

of which relay IWR controls the switch machines Y SMI 'andSMIa have been omitted to simplify'the i' drawings, but it is tobe understood that switches Y. Y

WI and WIaare caused to moveto normalorrtoYV reverse when relayIWRis energized in its normalor reverser-direction', respectively, and areY Y locked againstoperation WhenrelayV IWR is` dern energized;

A polar switch indication .relay IKR. isas'soci-fV ated with switches WI and Wla in the usualV manner, and it is'to Vbe'uriderstood Ythat relay IKRis energized to close its polar contactsrto the left when switches WI and Wld are locked normal andl to the right whenthe switches are locked `A similar arrangement is providedfor the con` trolY of switch W3rby relay SWR, the circuit for.V

relay SWR, like the circuit of lock magnet M3 of Fig. 1, including contacts 29 and 30 of relaysASTR and IES, contact 3U'b`eing shunted byav 'Contact 55 'of relay IKR which takesthe place of Contact R21/V' 'of Figjl and is closed whenfswitches Wl'and Wla are reversed. Thecircuits for, relaysrITPSand AITPSf`are-the'sameasin Fig. V1 except that the 'pick-'up circuits include Vback contactsS and ISf 'of signal control relays R2HS and LGI-IS, respectively, Vinstead V'ofthe lever contacts NL andlNR, Y

similarV to those employed in Fig. l except that polar contacts'M and 'I6 of relay IKR are substituted for lever :contacts NI andY Nm3, the cir- Y'and contact I4A in the circuit of relay AITPS is Y Y shunted'by normal contact I3 of relay IKR in place of Vlever Contact N312.'Y Likewise the circuits for the route locking relays YIES andV IWS 'areY cuits of Fig. 2'also including front contacts 53 J5 VlofY closed over back contact 62 of relay ITPS. Re#V and 54 of approach locking relays IELS and IWLS in place of contacts Ld and Rb of the signal levers, and contacts 58 and GS of time element relays B2TE and BliTE in place of contacts 38 and 39 of time element mechanisms A2TE and AIITE.

Approach locking relay IELS is normally energized and has three pick-uprcircuits, one of which may be traced from terminal B, contacts R2BI and R2AI closed by signals RZB and RZA, respectively, in the stop position, front contact 5I of an approach relay RQAR which is a repeater of track relay TR, back contact 5I] of thermal time element relay ZTE, relay IELS, to terminal C. The second pick-up circuit is similar to that just traced except that it includes back contact 52 of relay ITPS which bridges contact 5I when relay ITPS is deenergized. The third pick-up circuit includ-es contact EI of a stick relay 2TES controlled by relay ZTE. Relay IELS has a stick circuit which may be traced from terminal B,

, contacts RZBI and RAI, front contact 5l and Cil Winding ofA relay EELS to terminal C. Relays 2TE and ZTES serve to pick-up relay IELS in the eventy signal RZA or RZB is put to stop when there is a train approaching in section T and relay RZAR is consequently deenergized, as will hereinafter be pointed out. Relays IWLS, ITE and TES are provided with circuits similar to those of relays IELS but which are controlled by contacts L4AI and LlBI closed by signals LIA and L4B, respectively, in their stop position, and by relays AITPS and LAAR, the latter relay being a repeater of track relay AZTR.

It is believed that a clear understanding of the form of the invention shown in Fig. 2 can best be obtained by describing the various .operations which occur during the usual traffic movements. It will first be assumed that the operator has energized the signal control relay REI-IS in order to clear signal R2A for a train movement over track Y from left to right with switch WI normal. The circuits for clearing the signals form no part of the present invention and these circuits have therefore not been shown. It is believed sufficient to explain that these circuits are controlled in such a manner that either signal REA or RZB may be cieared depending upon the position of the polar contacts cf relay iKR and hence upon the position of switches WI and WI a, of the cross.- over, when relay RZHS is energized.

When the relay RI-IS is picked up, signal R2A moves to its proceed position, and signal contact RZAI, which is closed only when signal REA is at stop, opens the circuits for the approach locking relay IELS. Relay IELS accordingly releases and at its front contact 53 opens the circuits for route locking relay IES. Relay IES then releases, and its front Contact 28 opens the circuit foi` switch control relay I WR, so that theoperation of relay IWR through the medium of the remote controlled relays IX and lY is prevented, thereby locking switches WI and WIa against movement. Since the switches WI and W la are normal, the polar contacts of relay IKR will be to the left, as shown, so that contact 'I3 of relay IKR is closed to bridge contact I4, thereby preventing relay IES from interfering with the control of relay AITPS when the route set up does not involve track X. Contact 55 of relay IKR is open, and since contact 30 of relay IES is also open, relay SWR is deenergized to lock switch W 3.

lWhen the approaching train enters section IT, relays ITR and ITPS release, causing signal R2A to return to stop to close contact RZAI, whereupon the pick-up circuit for relay IELS becomes lay IELS picks up, closing contact 55 in the circuit of relay IES, but relay IES remains deenergized because contact I5 of relay ITPS is now open. As soon as the train enters section 3T, track relay STR releases andrat its front contact 29 opens another point in the circuit for relay 3WR. Relay R21-IS may now be released by the operator to close back contact 45 so that relay ITPS will pick up when the train vacates section IT, and then since contact 14 of relay IKR in the pick-up circuit for relay IES is closed, the closing of contact I5 of relay I'IPS will cause relay IES tc again become energized, closing contact 23 in the circuit for relay IWR to release the locking for switches WI and Wla. When the train vacates section 3T, relay 3TR will pick up to close contact 29 in the circuit for relay SWR to release the locking for switch W3.

It will'now be assumed that switches WI and Wla have been reversed and that relay R21-IS has been. energized to` clear signal RZB. YWhen the signal clears, contact RQBI opens the circuits for relay IELS and this relay releases, opening contact 53 to deenergize relay IES. The

route set up in this case does not include secrv tion 3T and the operation of switch W3 is not interfered with by the release of .relay iES because contact 55 of relay IKR is now closed to v the right bridging contact i of relay IES in the circuitfor relay SWR.

When the train vacates section iT, ifY it is short enough to be wholly included within the section U, track relay ITR will pick upA before relay AITR releases as pointed out in connection with Fig. 1. If the operator releases R21-IKS, relay ITPS will pick up when the train vacates section IT but relay IES will remain deenergized because its pick-up circuit is open at contact 'M` of relay IKR, and switches WI and WIa will remain locked by relay IES as long as the train remains wholly vWithin section U. When the train enters section AIT, relay AITR releases,

deenergizing relay AITPS to open contact 21 in the circuit for relay IWR and closing back contact 35'to complete the pick-up circuit for relay IES. When relay 'IES picks up its front contact I4 closes to prepare a pick-up circuit for relay AITPS and its front contact 28 closes one point in the circuit for relay IWR.

When the train vacates section AIT, relays AITR and AITPS pick up. Relay AITPS then closes contact 2'I'to complete the circuit for re-l lay IWR to release the locking for switches WI and Wla.

If the operator clears signal RZA or RZB and then returns the signal to its stop position manually, the operations which follow will depend on which route has been set up and also upon the condition of the approach section T. If section 'I' is unoccupied. and the operator releases relay RZHS to manually return signal RZA or RZB to stop, the pick-up circuit `for relay IELS becomes closed over contacts RZB! and RZAI and contact 5I of relay RZAR as Soon as the signal returns to its stop position. Relay IELS will then pick up and if switches WI and Wla are normal,` contact 'IIIv of relay IKR will be closed so that relay IES will pick up and the release of the switch locking will be obtained Vwithout delay. If, however, the switches WI and WIa are in their reverse position, contact 14 of relay IKR will be open, and to pick up relay IES to release the switch locking it will be necessary for the operator to energize the remote con- 'whichfmay be 'traced from terminalgB; contacts Contact B2i of relay IES- to Yterminal C. lt jisf'rto *Y Y Vbe; Il lnderst'ool that 'theV contactsV of the thermalY Y the end fof a predeterminedV heating period closes 1 5 its front'gcon'tactV 6 8Vb ridging contacts I4 and'35 f 2o;re1 ay'B 2'rE., after', a predetermined cooling pe;

'-rrorrnal'v position; andl back contact f6] f ag'ain *j fcloses to place the'relayL IWR'under f remote 'controlled relays V,I X V'and IY.'

C; Rela-y ZI'ES picksup, opening the circuit'for contact59 to Ycomplete' Vitsfstick circuit. Relay bridges contactsSI and '6 2in"th e pick-up circuit` for-relay IELSY. Relay 2TE@ i s nowideenergized,

1 pleteits stick circuitand 55,51 to releaserelay ZTES.

- lIt will-{next beassumedgtlia 1 Y, A operator deenergizes-relayzlitZHS; butf thatY the train 'doesnot Vjenter section A I Tr'but backsv out of (50v section "ITVYwith alviewV to making a subsequent VYrelaycIES'willhavebeen"deenergizedjand will The switches will therefore remainloked, Vsub-i Y Vv7 0"operation o f c trackand over the crossover and invclvingrelays f -relayshereinishownjare of {the bi-metallic type L ,and completing thefpick-'up Circuit for VrelayV IES.' v Relay IESthen picks up, completing y its Y. Vstick circuit, as VVwill be V clear from the Vdrawings;k I Yand atits backcontact 2;open sV the' circuit'for 1 riod Vthe vcontacts fofYV relay 132] TE restoreto'their ogntrol :or

' 25 j 1f i the approach -secuoniT is occupied; ifiays Y 45 relay-'ZTE and closing .front Contact 58 tovbrid'ge ZTES also closes lts'fifront contactjl which pletes :the pick-'up 'circuit forA relay; IELSyWhich fthen picks up, closing; front contact 5'I` to comopening back contact.V

'Y :-remains`obecause Contact 14 of re1ay `IKR isfopen.

' ,Y .j fjectgtoi manual release aftera timeldelayxbythe the emergency relay IER as alreadyj f L third s ection,} respectively;A in accordance with v thepositioniofthe crossover switches, meanso'r-f: ments fromjrigh t to'left over the upper stretch of Y" i e I Y meme Y Y Y Y trolled emergency; release relay` IER. When 'ref tionirithesame mannerlasthe correspondingrelay IER picks upf the thermalg time Velement YYrelay ABZI'E .becomes energized over a circuit and theirrnanner of operation will therefore bef clear 'without further Y explanation. Y Since,Y VhowV ever, the1upper stretchof track is not provided with 'a vswitch correspondingrtojW3 the route lockingIrelay I WS sprevented from releasing when contactj` 16"of relay IKR is Vin its normal position, and it follows that as in'Fig'. 1, relay IWS does not" fswitches WI fand Wlarare normal,VY It will' be. apparent, however, that when the relay YIKR; is Y Vin its reverse position andrelay LIIHS is picked up w o to clear signal LIB for a crossover move the opera# tion of relay IWS will be similar toi that ofrrelfayY 1' 1 IES as hereinbefore described. ff Y it will be'clear from theforegoin forms of Vmy invention'lerein illustrated provide fulltime locking protectionAVA against the opra- Y tion of vswitches WE- and Wld ifaftrainmoves over vention", itisunderstood that various changes andV modications mayY be made therein, within thej scope' Yof the appended'claims withoutdepartg ,ingrrirom'th'e' spirit andscopeof myfinvention;Y y' Havingthus described my invention, what I' L: l airn 'isp-' `v Y* tion of track adjoiningfoneof said sections,'=a j` f 1 crossover includingV track'switche's and extendin Y Lbetween saidfadjacent sections, 1a normallyY ener Yincluded- Yin Ya' locking circuit. *for said switches,

two signals including onelior' governigfrtraing movements over the routerextending from onefad jacentV section over the crossover tothe otheriand f fypone for governing train movements Yover the routeYV .extending from said-onefsection to saidY third VVsection,v YmeansY for Aeffecting the release 'of said if route lookngrelaywhen eithersignal is cleared; means including Vthe v.track relayj for saidone ad?Y 1 jacent s ection,forenergizingrsaid route locking?v relay rendered eiectiveswhen Ythe train; vacates rrrsaid one, adjacent s ectinipr'ovided VVthe route railway track each provided with,atia;ck circuit', I

including a normally energized track relayre' normallyrenergized route locking'relay;V having two'signals for governing train movements .into oneof said adjacent sections andover the crosse; over into the other adjacent Ysection orinto saidV effecting the release of said route locking relay;

lays 'andcircuits employed" in traffic movements Y from left to right over thellowerr stretch of track;

'control tl1e,locking 'circuits for track Y when, shortf time interval,Y -relay BZTE' opens' its 'back'.

Contact 61 in the circuito'f relay IWR, and atV` the 'crossover and fails for a timetofshuntthe, 'f

railway trackfea'ch'provided 'with a Ytrackicircuit:`` l

' `giz'ed routelocking relay having Va front contact 4a AY.estalolished includes saidthird section, and means leased when Vthe section 's'occupied, a third track 1 section adjoining oneY ofi-'said sections `including .l a Ysidingswithjfa crossover including 'twoltra'ckl switches for connecting Ysaid adjacentV sections,` a?

4 vfront{c ontacts includedin locking circuitsforYsaidf'fY' crossover switches and ffor said'j sidingY switchfjyV when either signalis cleared, means lcontrolled v 'by the 'track relay of said one section for pickingV 7 5 up said route locking relaywhen the train vacates such section provided the route established includes said third section, means controlled by the track relays of both adjacent sections for picking up said route locking relay when the train vacates one and' enters the other of said adjacent sections provided the route established includes the crossover, and means for bridging the route locking relay contacts included in the locking circuit of the siding switch when the route established includes the crossover.

3. In combination, two adjacent sections of railway track each including a track switch and connected by a crossover track to provide a traflic route at times from one section to the other when said switches are reversed, a plurality of manually controllable signals for governing train movements into said sections, switch locking means for locking said switches against movement when a signal is cleared for the movement of a train rom one adjacent section to the other, means -for releasing said locking means automatically when a train governed by such signal has entered and vacated such other section, and time element means effective to cause the release of said switch locking means after a delay period in the event the cleared signal is returned to its stop position manually.

4. In combination, two adjacent sections of railway track each including a track switch and connected by a crossover track to provide a traffic route at times from one section to the other when said switches are reversed, signals for governing train movements into said sections, switch locking means for locking said switches against movement when a signal iskcleared, means for releasing said switch locking means automatically when a train which has entered one section with said switches reversed enters and vacates the other section, means forI also locking said switches against movement as long as the section rst entered by the train is occupied irrespective of the position of said switches, time element means for at times effecting the release of said switch f locking means in the event a signal is returned to its stop position manually, and other means for effecting the immediate release of said switch locking means when a signal is returned to its stop position manually provided the switches are normal and there is no train approaching within a predetermined distance of the signal.

5. In combination, two adjacent sections of railway track each provided with a track circuit, a crossover including two track switches connesting said sections, a relay for each section controlled in accordance with the condition of the associated track circuit, a signal for governing the movement of traffic from one of said sections to the other, a signal lever for clearing said signal, a route locking relay having a pick-up circuit including a normally closed contact oi said lever, a front contact of one of said track controlled relays and a back contact of the other track controlled relay, a stick circuit for said route locking relay including one of its own fronty contacts and the normally closed contact of said vlever, and means preventing the movement of 'said switches when said route loclnng relay is deenergized or when either track controlled relay is deenergized.

6. In combination, two adjacent sections of railway track each provided with a track circuit, a crossover including two track switches connecting said sections, a relay for each section controlled in accordance with the condition of the associated track circuit, signals -for governing the movement of traiiic into said sections when the switches are normal and from one section to the other when the switches are reversed, a switch lever operable to a normal or reverse position for operating said switches to normal or to reverse, a signal lever operable from a normal to a reverse position to clear one or another of said signals depending on the position of said switches, a route locking relay having a pick-up circuit including Y normally closed contacts of both of said levers and a front contact of one of said track controlled relays, a second pick-up circuit for said route Ylocking relay including a normally closed contact of said signal lever, a front contact of one of said track controlled relays and a back contact of the other track controlled relay, a Ystick circuit for said route locking relay including its own front contact and a normally closed contact of said signal lever, and locking means preventing the movement of said switch lever when said route locking relay is deenergized or when either track controlled relay is deenergized.

7. In combination, two adjacent sections of railway track connected by a track switch, a signal for governing train movements over the route including said two sections, signal control means for clearing the signal, a normally closed track circuit for each section each including a track relay, a normally energized stick relay for each of said sections, a normally energized route locking relay, means for releasing said route locking relay when said signal is cleared, means for releasing the corresponding stickfrelay, manually controlled means for picking up said stick relays, means for picking up said route locking relay eiective when said signal' is put to stop provided the stick relay for one section is energized and the stick relay for the othery section is deenergized, and means elIective when said route locking relay is deenergized or when either track relay is deenergized to prevent operation of said switch.

8. In combination, a railway trafc route including two adjacent sections of railway track connected by a track switch, a normally closed track circuitV for each section each V'including a track relay, a normally energized stick vrelay for each of said sections, a normally energized route locking relay, a signal for governing train movements over said traffic route, manually operable signal control means for clearing the signal, a normally energized approach locking relay, means actuated by the signal when cleared to effect the release of said approach locking relay, means responsive to release of the approach locking relay for eiecting the release of said route locking relay, means including one of said track relays and one of said stick relays for picking up said approach locking relay' when a train governed by said signal enters the first section of the route, means including the other track relay and the other stick relay for completing a pick-up circuit for said route locking relay when said train enters the second section of said route, and means effective when said approach locking relay or said route locking relay or either track relay is deenergized to prevent operation of said switch,

9. In combination, a rst and a second section of railway track, a track circuit for each section each having a track relay, a track switch for establishing a traffic route from said rst to said second section when said switch is vreforfclearing Vsaid signals, meansreleasingvsaid route locking relay'when either signalis cleared, means controlled by the track relay IoriV the firstl .sectionfor'picking up said route'lockingV relay I when atrain'governed by-said first signal Vvac'ate's l the'first section, Ymeans*controlled by thertrack relay for the'secondV section for picking up Ysaid4 `V`r'oiite' locking relay when a Vtrain governed by YAYsaid second lsignal enters V4the Y"second"section,- manually controllable time "element means Yef-` Vv"lectiv'e to pick-upsaid route locking relay'when @a Vcleared Vsignal'is man`ually restored ato stop,

' fand meansV preventing the operation of the track Y switch' -whensaidfronte locking relay is deener'- giz'edfor when either ofsaid track'relays is 'de- 10. 'In combination, a stretch}oflrailwaytrack L l, divided' intoga firstanda secondfsection, aA first anfd a second Y signal; for VYgoverning; traic move- V,ments -in',op'p'osite directionsl over said Ystreteh, Y.

Vv,manually controllable means for 'clearing said Vrst signal, ,otherj manually controllable means ffo'r'clearingsaid secondY signa'La first 'and a secondlrrroute locking relay,` a rst andV1 a secondY stick relay, a -YpicVk-'iip circuit/for said rstfstick Y f reiay arranged .to be opened if sin secondrpuie locking relay isvdeenergized orV Vii Vsaidr'st signal Yfis clearedjbyrjsaldl rst manually controllable`v means, a Ystickcir'cuit lfor fsaidY first stick .relay Vclosed only, if said/first track section is unoc-l fY v cupied, da.tpick-upv?circuit for said second stickf re`` l "-layr' arranged; to bepopened saidf rst Vroute lockirigf'relag.isVV deene'rgized or; if said second Vvsignal iscleared by saidI other'manually control'- 1 lablezmeans, aV sti'ck'circuitifor said 'secon'dsticks VYfrelayclsed,r'ily if said second track sectionris unoccupied, a pick-up'circuit for said'firs't routeV locking relay controlledgby a front contact-'of Ysaid n rst stick relay'and by a back contact Vof y f. saidjsecond stick.Y relayQa stick circuit for said first route'lockin'g relay'closed if said first signal isfcontrolled to flndicatestop, a 'pick-upcir'ciiit' Yforsaid second routelocking relay controlled by afrontfcontactlof said secend` stick relay and Yia back` contact of `said'rststick relay, a stick circuit for' said second?y route lockingy relay' closed ifV said. isec'ondsignalis controlled.,to'jindicate stop;V and track switches controlled bysaid first and-second route locking relays.' i. Vl1. Injeombinationfa stretchaof railway track VV"dividedinto aiirstl and-a; second section, aiirSt Yand a second signal for l'governing traffic movements in opposite VVdirectionszr over Vsaid;stretch,

Ymanually controllable'. Vmeans for Yclearing said Iirst Vsignal,V other.,manually,A controllable 'means "fori `clearing?'said secondgsignal, ja rstLand ngai" 'second' route locking 'relayQfa ilrst and a second j V sti'ckrelay, fa'pick-up'l and a stickcirc'liit for said Y iirst Ystick grelaylfeaj'ch Y off'which isv opened byf a Ytrainfentering'fsaidfnrst section, al'contact con-r A S ftrolledbyfsaid first manually controllable fmeans and]arcontact'controlled by said second route g lcckin'g'relay'for alsoopening'the pick-up'circuit t -fcr' Vsaid ,rstv'rstick relay if said ,rstsig'nab is f 1 'cleared or if saidsecond route 4locking relay Vis l'deenergized respectively, apickupand aY stick circuit for said second stick Vrelay eacliof which Y fis opened. by a trainlentering said second-' section, I `contactY Ycontrolled t by.Y said second rmanually i 'Y route'locking relays.

controllable means andra csti'i'ntactV` controlled by said rst reute lockingrelay for Valso opening the pick-up circuit forsaid second stick Vrelay iffsa'id second signal isV cleared, a front contact of said'v secondstick relayand a back Vcontactofsaid`Y iirst stick relay included in series in the pick-up circuit-for saidV second routerlocking relay, and 1 i.

trafiic' governing means for/said stretch'of track contrc'alledv by said stick and route locking relays. 12. In combination, a stretcliofu'railway track`V 20 Vand afsecondsignal for governing traffic, move-V Y Y mentsjin opposite directions overl said, stretch,

divided into fa; rstand a Vsecondsection, a first manually controllable means forc'lean'ng said sig- 'nals, a'first and a second route `locking relay, a 25,

first and a second stickrelay, means for deener` gizing said rstorsecond route locking relay whensaid first orsecond signal respectively is cleared,jmeans for d'eenergizing said7 first Vor second stick relay when a 4train enters said first orsecond track section respectively,f `1^r 1eansffor Venergizing said rst or'second stick relay'wheng said'rst or second signal respectivelyiscontrolled 'gto' indicatestop, means forfenergizing;Y said first routelocking relay whensaid first stick relay-is j; energized'and said second stick relayisideen?,`Y

ergized, means forenergizing Vsaid second router* locking relay when said second stickrrelay is en-j1 Y' ergized'and `said rstzstickY relay isdeener'gized,

and -trailifc" governing means for said stretchfof"`V` if 1 track controlled by said'stickfand route'flocking relays.

713, In'combination, a stretch of railway" for governing traic movements over said stretch,-

Vdivided into a rst andra second section, a signalVv 1 for governing tralic movements over said stretch, Vmanually controllable means for clearingrsaidosig- "nal, a route locking relay, a stickA relay, means j for deenergizing ,said route` lockingrelay'wl'ienV said signal isclearedpmeans for deenergizing said stick-'relay/Ywhen atrainfenters saidlrst section,` Y means'for energizing said stick relay if saidV sig- V :nal is lcontrolled to indicate stop providedthex train leaves said rst section, Vmeans fr energiz-Y VingV said route locking relayV ivfjsaid stick *relay isenergized anda trainV enters said secondsec'- tion, and Yothertraific governing'l'means for said,VV

stretch controlled by saidstickand route' locking Yrelays. rf j i Y 1 14. In combination,-astretch of railway track "f divided intol a first and a secondsection, a signal manually controllable means for clearingfsaid signal, arcate `'lockingYV relay, a stick relay, a con- 1 trol circuit fr-said-route locking-relayfopened if Y' 'Y A said signal is cleared, a second control circuit for `said'r'iute 'locflningvr relay closed if Vsaid stick relay` Y is energized Vanda traink enters .said second track` section, a control circuit for said stick relay f Yopened'if said first tracksection lis occupied byV a train, a second controlcircuit for said stick re-V Y Y' VcateV stonand other traiiic Vgoverning nieansfor` 7 controlledby'said stick and lay closed when'said signal is controlled tofindisaid stretch of track HARRY C.VAN'I'iissiiiL. v

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