US2027188A - Highway crossing signaling system - Google Patents

Description

Jan 7, 1936. v D, J, MCCARTHY 2,027,188

HIGHWAY CROSSING SIGNALING SYSTEM Filed May 23, 1934 J wloi Fa) m Pig/g F i a 3% (a \J" J W K INVENTOR DANIEL J. McCARTHY (34% MATH i atentecl Jan. 7, 1933 7 U ET E ,MPEATENT OFFICE 2,627,188 HIGHWAY CROSSING SEGNALING SYSTEM DanielJ,.McCarthmElgin,IlL, assignor to Asso-' elated Electric Laboratories, Inc., Chicago, 111., a co'rporationof Delaware 'Application-May-23', 1934;, Serial lvohizmozc 6 Claims. (01.246-1-126') "The present invention relates in general to railway crossing signal control-circuits for" controlling signals or otherapparatuslocated at intersectionsof railways and highways to warn those using the highways when a train is ap- --proaching. I

In the present highway crossing signal systems there is--no"provision for differentiating between high and low speed trains approaching across- 0' --ing, and-the-crossing signal is operated-from a definite and" fixeddistance from the crossing by all trains regardless of their approaching speedn The operating elementgoperated by the a-pproachingtrain for controlling" the crossing signal; must be put themaximum distance away fronr the-crossing to give adequate-warning againstthe fastest trains. Under "this condition, a train-approaching at aslowrate of speed will -operate the crossing signal and stop highway gg trafficdonger than is necessary. This long signaling :operation beforethe slowlyapproaching train actually reaches the crossing hasproven -'-dangerous because it invites careless motorists to takechances-in passing over the'crossing while the train is approaching andthe signal is operating.

Accordingly, the mainobject of the present invention is the provision of new and novel circuit arrangements for differentiatingbetween high --and slow speed trains "approaching a crosslng' so that the timelengthofthe warning'given by the signal before the trainactually reaches the cross- 'ing is substantially the sameior fast andslow moving trains.

The above and other objects will be apparent 'from'the followingspecification when read in connection with the accompanying drawing.

Referring nowto the drawing, T represents the ""two rails'of a railroad track-on which trains l opproach the highway=crossing in the direction indicated by thearrows Alongthe-inside of one of the. rails are placedcontactors 2, 3, 4, 5; and 6 which are operated. by the wheels of a train when Hpassing thereover; These contactors may be substantially of the same design and operation as disclosed in theapplication oi..H. F. Obergfell and'G. W. Eickenberg, Serial No. 639,558,.filed ,"October 26, 1932, wherein the. plunger is operated by the train wheels to cause. the" operation of the circuit controlling contacts inmtheassociated housing. The corresponding circuit controlling 1, scontactsin'the present. drawing are indicated at '5 2,3, 4, 5, and 6 whereinsuchcontacts are operatedby the associated: plungers represented by small circles placed along the inside of the lower rail.

The contactor 2 is placed on the. left-handside of the highway crossing, the contactor 3 on,the

right-hand side of the highway crossing,;-and the contactors 4, 5, and 6.. at varying distancesfrom the crossing best suited to accomplish the desired -result as more fully explained hereinafter.

A highway crossing signaldesignated as ,l ,:may

-be of the fiashing,.audible, or any standard crossingsignal type including automatic gates, The contacts of the. contactor control circuits of a number of relays, :two of which--namely, relays 8 and 9-are of the slow-releasing type,,,having copper slugs on their armature ends as, indicated by the cross-hatched sections .thereoi. ll, l3, and 26 designate batteries forcontrolling the operation of the highway signal I andgthe relays. If desired, 26 and I3 may be considered as the same battery. The relays, contactors,;and circuits are shown in their normal .condition or at a time when there is no signal being given at the highway crossing. Since all of the relays, except relay ID, are normally energized, it is believed advisable to describe the circuitsby means of which such relays are maintained in their normal operated positions.

The circuit for maintaining relay l2 energized extends from one pole of battery .l3, ,through armature ll, winding of relay l2, armatureof relay l6, and conductors I5 and M to theother pole of battery I3. Relay I6 is maintained energized over a circuit extending from one pole'of battery l3, armature l1, winding of relay l6, and conductor M to the other pole or battery l3.

Relay I8 is maintained energized over the-following stick circuit: From one pole of battery '13, through the winding of relay l8, armatur'e123, contacts of contactor 3, conductor 2|,1 lower normally closed contacts of contactor 4, conductor 20, contacts of contactor 5, and conductors llfl and 14 to the other pole of battery l3. Thecircuit 'for maintaining relay 9 energized extends ,from

one pole of battery 26, through the winding of relay 9, and armature 31 to the other poleof battery 26. Relay 8 is maintained energized over a similar circuit including armature30. Relay I is maintained energized over a locking or socalled stick circuit as follows: From one pole of battery 26, armature 28, winding of relay Land contacts controlled by contactor B to the other pole of battery 26.

r In order to describe the invention it will be assumed that a train is approaching the high- Way crossing in the direction indicatedby the arrow and that in so doing the wheels of the train operate contactor 6 to open the associated contacts. In response to the opening of the contacts controlled by contactor B the stick circuit of relay 1 is opened with the result that this relay thereupon deenergizes. At armature 28 relay I removes a shunt from around contacts 34 of contactor 4 and at armature 38 opens the circuit to slow releasing relay 3. After an interval slow releasing relay 8 deenergizes and at armature 3i opens the circuit of slow releasing relay 9. If desired, additional slow releasing relays, such as 8 and 3, may be added and connected in a like manner to increase the time interval before the last of such relays deenergize. After an interval the last slow releasing relay, in this case relay 3, deenergizes and at armature 32 completes the circuit for energizing relay III over the following circuit: From one pole of battery 26, winding of relay I3, and armature 32 now closed to the other pole of battery. At armature 33 relay Iii closes a shunt around the contacts controlled by contactor 5.

The operation from this point on is different dependent upon the speed of the approaching train or is dependent upon whether the contacts controlled by contactor 5 have been operated by the train before relay I3 has been energized to close contacts 33. In case of a fast train the contactor 5 will be operated before relay III has had time to energize and close contacts 33 while in the case of a slow train the relay I3 has had sufficient time to energize and close its contacts 33 to shunt the contacts controlled by contactor 5.

It will now be assumed that the train approaching is a fast train and therefore the contacts controlled by contactor 5 are operated before relay It] operates its armature contacts 33. Under this condition the operation of the contacts controlled by contactor 5 opens the previously traced stick circuit for relay I 8 whereupon relay I8 deenergizes. At armature 23 relay It opens a further point in its stick circuit and at armature I? opens the previously traced circuits of relays I2 and I3 whereupon such relays deenergize. At the contacts controlled by relay it a further point is opened in the circuit of relayIZ, At armature 23 relay I2 closes the circuit for operating the highway crossing signal I over an obvious circuit. From the foregoing it will be seen that a fast train starts the operation of highway signal I in response to the operation of contactor 5.

In the case of a slowly approaching train the signal I will not start operating until the train reaches and operates the contacts controlled by contactor 4. In response to'a slowly approaching train operating contactor I5, relays I, 8, and 9 deenergize and relay I0 energizes as previously described. In this case relay It has energized and closed contacts 33 before the slowly approaching train has operated contactor 5 and therefore, since contacts 33 shunt the contacts controlled by contactor 5, the operation of these contactor contacts is Without effect. During the time the contacts controlled by contactor 3 are open the stick circuit for relay I3 is maintained through contacts 33 of relay I 0. When the slow train operates contactor I the stick circuit of relay I3 is opened at the lower normally closed contacts with the'result that relays I3, I6, and I2 deenergize and highway signal I is operated as previously described. From the foregoing it will be seen that a fast train operates the highway signal when contactor 3 is operated and a slow train operates the highway signal when the contactor 4 is operated. Contactors 4 and 5 are therefore placed at suflicient distances from the crossing so that signal I will operate for substantially the same length of time before the train, whether fast or slow, actually reaches the crossing.

Each train, regardless of whether it is a fast train or a slow train, prepares the circuits so as to be reset for the next train. Whenever a train operates contactor 4, contacts 36 close an energizing circuit for relay I as follows: From one pole of battery 26, conductor 33, contacts 3 conductor 31, winding of relay I, and contacts controlled by contactor 6 to the other pole of battery 26. At armature 28 relay '1 closes its stick circuit and at armature 33 completes the circuit for energizing slow-to-release relay 3. At armature 3|, relay 8, upon energizing, closes the energizing circuit of relay 9. Relay 3, upon energizing, at 20 armature 32 opens the circuit of relay II) which thereupon deenergizes to open at armature 33 the shunt circuit around the contacts of con tactor 5. Relays I, 8, 3, and III are now reset in their normal condition in preparation for the next approaching train.

Contactors 2 and 3 are positioned with respect to each other so that they would be spanned by one or two cars of a train in such a way that when contactor 2 is closed contactor 3 would be immediately opened if the train still spans the crossing. This arrangement prevents the reenergization of relay I8 until the last car has cleared the crossing so that signal I will continue to operate as long as any portion of the train is on 35 the crossing. However, when the last car passes the crossing contactor 2 is operated to close its contacts at a time when the contacts controlled by contactor 3 are closed. Under this condition a circuit may be traced for energizing relay I8 as follows: From one pole of battery I3, winding of relay I 8, contacts of contactor 2 now closed, contacts of contactor 3 now closed, conductor 2|, lower normally closed contacts of contactor 4, conductor 23, normally closed contacts of contactor 5, and conductors I9 and I I to the other pole of battery I3. At armature 23 relay I8 closes its previously traced stick circuit through contactors 3, 4, and 5 and at armature I'I completes the circuit for energizing slow-to-operate relay I3. Relay I6, upon energizing, completes at its armature a circuit for energizing slow-to-release relay I2 by way of armature I'i. Relay I2, upon energizing, at armature 25 opens the circuit to highway signal I, whereupon the signal ceases to operate. Slow-to-operate relays have copper slugs on their heel end as indicated by the upper full black section of relay I5. All of the apparatus is back to normal condition ready to operate in the same manner as just described for the next approaching train.

In a co-pending application executed by me of even date herewith, Serial No. 727,025, filed May 23, 1934, I have shown and described circuit arrangements whereby the speed of a train between two given points determines whether or not a signal is to be operated. From the foregoing description it will be seen that this feature is also disclosed in the present application wherein the speed of the train between contactors 6 and 5 determines whether signal I is to be operated in response to the operation of contactor 5 or in response to the operation of contactor 4. In the co-pending application a railroad grade crossing signal is operated to danger position or remains in -.e-,ozr ,res J the clear; 'position 'togovern "whether the train 1 mfay proceed across the railroad'grade crossing dependent upon the speed of 1 the *trainbetween two 'givenpoints; while'intthe instant application the highway crossing signal is operatedor not operated in response to the Operation of conbetween contactors 6 and 5. The co-pending apto the specific disclosures not. shown :in the copending application.

Itwill be .understoodthat while only one track with traffic in one'direction has been illustrated,

a similar arrangement is provided for a second track having traflic in the opposite direction. Also while the circuits and arrangements provide for trains having speeds within two limits, it will be understood that any number of limits can be had by multiplying the units in an obvious mannner.

What is considered new and is desired to have protected by Letters Patent is set forth in the appended claims.

What is claimed is:

1. In a signaling system for signaling the approach of trains at a crossing, a plurality of contacts located at predetermined points along the track and operable in succession by a train approaching the crossing, a normally energized start relay, a stick circuit for said start relay in-' cluding the first of said contacts to be encountered by the train, said stick circuit opened in response to the train operating the said first con tact to release said start relay, a normally energized signal controlling relay, a stick circuit for said relay including the second and third of said contacts successively operated by an approaching train, slow releasing means initiated in response to the release of said start relay, means operated by said slow-releasing means for shunting the said second contacts after a predetermined time to maintain the stick circuit of said signal controlling relay only in case the said second contacts are operated after said second train operated contacts are shunted, and the operation of said third contacts by the approaching train thereafter opening said stick circuit to release said signal controlling relay.

2. In a signaling system for signaling the approach of trains at a crossing, a plurality of contacts located at predetermined points along the track and operable in succession by a train ap-' proaching the crossing, a normally energized start relay, a stick circuit for said start relay including the first of said contacts to be encountered by the train, said stick circuit opened in response to the train operating the said first contact to release said start relay, a normally energized signal controlling relay, a stick circuit for said relay including the second and third of said contacts successively operated by an approaching train, slow-releasing means initiated in response to the release of said start relay, means operated by said slow releasing means for shunting the said second contacts after a predetermined time to maintain the stick circuit of said signal controlling relay only in case the said second contacts are operated after said second train operated contacts are shunted, the operation of said third contacts by the approaching train thereafter opening said stick circuit to release said start and relay, and means controlled by some of said contacts when operated for retactor dependent upon the' speedof-the train "-ingtrain, said stick circuit opened in response to the-train operating said first contact to release saidrelay, slow releasing means initiated in--resaid slow-releasing means.

' 3: -In asignaling system for signaling the approach oftrains at a crossing, a plurality of contacts-located at predetermined points along the 5 track and-operable in succession by a train approachingthe crossing, a normally energized start relay, a stick circuit for said relay including the first of said contacts operated by an approachsponse to the release of said start relay, anormally openzshunt circuit around'the second of said contactsymeans operated by i said slow-acting means for closing said shunt circuit around the said second contacts after a predetermined time, a signal controlling relay operated in response to the operation of either said second or third contacts dependent upon whether said shunt circuit is openedor closed at the time the said second contacts are operated by the approaching train, and signaling means at said crossing operated in response to the operation of said signal relay to warn traffic of an approaching train.

4. In a signaling system for signaling the approach of trains at a crossing, a plurality of contacts located at predetermined points along the track and operable in succession by a train approaching the crossing, a normally energized start relay, a stick circuit for said start relay, said stick circuit opened in response to an approaching train operating the first encountered one of said contacts to release said start relay, a chain of normally energized slow-releasing relays initiated in their releasing operations in response to the operation of said start relay, a normally open shunt circuit around the. second of said contacts, means responsive to the release of the last slow releasing relay in the chain for 40 closing said shunt circuit around the said second contacts, a signal controlling relay, said signal relay operated in response to the operation of either said second or said third contacts dependent upon whether said shunt circuit is open or closed at the time said second contacts are first operated by the approaching train.

5. In a signaling system for signaling the approach of trains at a crossing, a plurality of contacts located at predetermined points along the track and operable in succession by a train approaching the crossing, a normally energized start relay, a stick circuit for said start relay, said stick circuit opened in response to an approaching train operating the first encountered one of said contacts to release said start relay,

a chain of normally energized slow-releasing relays initiated in their releasing operations in response to the operation of said start relay, a normally open shunt circuit around the second of said contacts, means responsive to the release of the last slow-releasing relay in the chain for closing said shunt circuit around thesaid second contacts, a signal controlling relay, said signal relay operated in reponse to the operation of either said second or said third contacts dependent upon whether said shunt circuit is open or closed at the time said second contacts are first operated by the approaching train, and other of said contacts operated by said train for reenergizing said start relay to complete its stick circuit and reset said chain of relays and for resetting said signal relay. 6. In a highway crossing signaling system, a

. highway signal and control means therefor having a slow operating device initially started in operation in response to the operation of said first set of contacts by a train approaching the crossing, a normally open shunt circuit around said second set of contacts, means operated by said slow operating device when fully operated for closing said shunt circuit around said second set of contacts, said signal control means and said signal always operated in response to the opening of said series circuit by the train operating said third set of contacts, said signal control means and signal operated in response to the operation of said second set of contacts by the train opening said series circuit only in case said second set of contacts are operated before said slow operating device is fully operated to close said shunt circuit around said second set of contacts, and the operation of said fourth set of contacts by said train maintaining said series circuit open to maintain said signal control means and signal in operated condition.

DANIEL J. MCCARTHY.

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