US2022708A

US2022708A - Railway traffic controlling apparatus

Info

Publication number: US2022708A
Application number: US674839A
Authority: US
Inventors: Paul H Crago
Original assignee: Union Switch and Signal Inc
Current assignee: Hitachi Rail STS USA Inc
Priority date: 1933-06-08
Filing date: 1933-06-08
Publication date: 1935-12-03
Anticipated expiration: 1952-12-03

Description

Dec. 3, 1935. R CRA@ 2,022,708

RAILWAY TRAFFIC CONTROLLING APPARATUS Filed June 8, 1955 2 Sheets-Sheet l '.66 l HIS ATTORNEY Dec. 3, P. H .CRAGQ RAILWAY TRAFFIC CONTROLLING APPARATUS Filed June 8, 1953 2 Sheets-Sheet 2 Patented Dec. 3, 1935 UNITED STATES PATENT OFFiCE RAILWAY TRAFFIC CONTROLLING APPARATUS Application June 8, 1933, Serial No. 674,839

17 Claims.

My invention relates to railway traffic controlling apparatus, and has for an object the provision of apparatus controlled by a car for causing operation of a traffic controlling device when a car passes over a given track section in less than a predetermined time interval.

I will describe three forms of apparatus embodying my invention, and will then point out the novel features thereof in claims.

In the accompanying drawings, Fig. 1 is a diagrammatic View of one form of apparatus embodying my invention for causing the operation of a railway switch when a. car approaching the switch passes over a given track section in less than a predetermined time interval. Fig. 2 is a diagrammatic View of a second form of apparatus embodying my invention for controlling the operation of a highway crossing signal located at the intersection of a highway with the stretch of railway over which traic normally moves in one direction. Fig. 3 is a diagrammatic View of apparatus for controlling the operation of a highway crossing signal located at the intersection of a highway and a stretch of single track railway, and which apparatus also embodies my invention.

In each of the several views like reference characters designate similar parts.

Referring to Fig. 1, the reference'

characters

2 and 3 designate the trac rails of a stretch of railway which include a railway switch 4. The traino rails are divided into three track sections, ST, 2T and 3T by means of the Vusual insulated rail joints, the switch 4 being located in the section 3T. Each track section is provided with the customary track circuit including a source of current such as a battery 5 connected across the rails at one end of the section and a track relay R with an exponent corresponding to the section connected across the trafc rails at the opposite end of the section. It is to be noted that the track relay ITR is normally energized over a stick circuit easily traced and which includes its own front contact. The pickup circuit for the relay ITR extends from the rail 2 over wire' extending from the terminal B of a convenient 5- source of current such as a battery, not shown, over front Contact i I of the track relay 3TR, back contact I2 of relay WR, controller contact I4-I5 operated by the motor and closed except when the switch 4 is moved to the full normal posi- 1'0" tion, armature I3, back contact I6 of relay WR, and field winding Il to the opposite terminal C of the current source. At such time as relay WR is energized in a manner to be later described, current flows from the terminal B of the 15.1

current source over front contact I I of relay STR, front contact I8 of relay WR, armature I3, controller contact iii-l operated by the motor and closed except when the switch 4 is moved to the full reverse position, front contact of relay 20 WR, and field winding il to the opposite terminal C of the current source. The flow of current in armature I3 when relay WR is energized is such as to cause the motor M to rotate in a direction for operating the switch 4 to its reverse 25 position, whereas the flow of current in armature I3 when relay WR is deenergized is such as to cause the motor M to rotate in a direction for operating the switch 4 to its normal position. It follows that with relay WR deenergized the switch 4 is set to direct a car to the track IUA, and with relay WR picked up the switch is set to direct a car to the track IUB.

Associated with the track section IT is a time measuring equipment comprising a flasher relay NF and a relay chain designated as a whole by the reference character CR. The two windings 2| and 22 of the flasher relay NF are normally energized serially as will be readily understood by an inspection of Fig. 1. The parts of the relay are so proportioned that with the two windings serially energized, the

armatures

23 and 24 remain in the position to which they were last moved. As will shortly appear, however, the control circuits for the relay NF are arranged in such a manner that the

armatures

23 and 24 normally occupy the position illustrated in the drawings. At such time as the winding 22 is short-circuited and winding 2l energized, the

armatures

23 and 24 are shifted to the left-hand position, that is, 50 to the position opposite that illustrated in Fig. 1. At such time as winding 2| is short-circuited and the winding 22 energized the

armatures

23 and 24 are shifted to the right-hand position, that is,

to the position illustrated in Fig. 1.

. 28 a shunt path around the winding 2|.

The operation of the asher relay NF is governed jointly by the two track relays ITR and ZTR to cause operation of the relay during the time a car is travelling through the track section IT, and to stop the operation of the relay as the car passes into the section 2T. The track relay ITR when shunted closes at its back contact 25 a shunt path around the winding 22 and which extends from the center connection 25 over right-hand contact Y2`| of armature 23, back contact 25, and front contact 64 of relay ZTR. Under this condition, the armatures 23 and '24 are shifted to the left whereupon armature 23 opens the above-traced shunt path aroundrthe winding 22 and closes at its left-hand contact Winding 22 is now energized and the

armatures

23 and 24 are shifted back to the right-hand position. It follows that as long as the track relay ITR remains down and the track relay 2TR is picked up, the relay NF is operated to alternately shift its

armatures

23 and 24 from one side to the other. The parts of the relay NF are so proportioned and adjusted that the

armatures

23 and 24 make substantially 30 cycles per minute, that is, they make a complete'moveinent-once every two seconds. The flasher relay NF may be any one of Vseveral types but a preferred type is that disclosed and claimed in the United States Letters Patent Reissue 1'7 ,252 to C. S. Snavely and W. B. Wells, for Electrical relays. I have found that a relay of this construction when connected in the manner shown in Fig.,l has excellent voltage characteristics and a remarkably uniform time for each operating cycle.

The relays IR, 2R, 3R, 4R and 5R of the relay chain CR are each of the direct current neutral type constructed with'a continuity transfer contact. For example, the armature 29 of the relay !R engages the front or transfer contact 3D before that contact becomes disengaged from the back `contact 3|. For each operation of the flasher relay NF to one side or the other, a relay of the chain -CR is picked up and then retained energized over a stick circuit, disconnecting at the same time a control circuit to be later described, and closing at a front contact the pickup circuit for the neXt succeeding relay. Assuming the track relay |TR to be shunted and the flasher relay NF operated as described hereinbefore, the closing of the back contact V32 of relay ITR makes possible'a pickup circuit for the rst relay IR of the chain when the relay NF makes its rstV swing toward the left. This pickup circuit can be traced from the B terminal of the current source over back contact 32, wire 33, left-hand contact 34 of armature 24, back contact 3|, transfer `contact 30 and winding of the relay IR to the opposite terminal C of the current source. Relay IR on picking up closes its stick circuit Yfor shunting around the'armature 24, and which includes terminal B ofthe current source, back contact 32, wire 33, armature 29, transfer contact 35, winding of relay-'IR and the battery terminal C. With relay IR picked up, the next swing of Varmature 24 to the right completes the pickup circuit for the second Vrelay, 2R of the chain. This pickup circuit for relay 2R extends from battery terminal B overback con- Y tact 32, wire 33, right-hand contact 35 of armature. 2`4, front contact 36 of .relay IR, back concludes the back contact 32 of relay ITR and its own armature 39. With the second relay 2R retained energized, the second swing of the arma- Y ture 24 to the left completes the pickup circuit for the third relay 3R of the chain, and which includes battery terminal B, back contact 32, wire 33, left-hand contact 34, front contact 40 of relayV 2R, back contact 4| of relay 3R, transfer contact 42 and winding of relay 3R and the C terminal of the current source. A s soon as relay 3R has picked up, it is retained energized by the closing of its stick circuit which includes its own armature 43, and thus the second swing of armature 24 to the right closes the pickup circuit for the fourth relay 4R of the chain. This pickup circuit for relay 4R extends from the battery terminal B Vover back Contact 32, wire 33, righthand contact 35, front contact 44 of relay 3R, back contact 45 of relay 4R, transfer contact 46, and winding ofV relay 4R to the opposite battery terminal C. Relay 3R, when picked up, is retained energized byrits stick circuit which includes its own armature H5. With relay 4R picked up to close its front contact 4l the next swing of armature,V 24 to the left completes a pickup circuit for the fth relay 5R of the chain as will be readily understood `by an inspection of Fig. l aud which pickup circuit includes its own back contactV 43 and transfer contact 49. Relay 5R is then retained energized over its stick circuit which includes its own armature 50. It follows that armature 24 is operated to make one complete cycle in a predetermined time interval and that the complete time of operation is summed'up by the number of relays of the chain picked up. Although I have shownV only live relays for the chain CR, it is clear that any number of relays may be added to the chain, and pick up and stick circuits provided for each relay whereby any desired time of operation for the relay NF may be measured. It is to be noted that the relays of the chain CR are not dropped as they are passed as is the customary manner for relay'time chains, but all preceding relays to the one last picked up are retained Yenergized by individual stick circuits.

The relay chain CR controls the switch controlling relay WR in the following manner: At such time as the track relay ZTR is shunted to close its back contact 5i a circuit is completed from the terminal B of the current source over back contact 5I,`wire 52, back contacts53, 54,

contact 59 of the trackrelay 3TR and its own front contact 53. Y Y

A car entering the track section IT of Fig. 1 will drop the track relay ITR and start operation of the flasher relay NF to pick up successively the relays of the chain CR. If the speed of the car is slow enough all the relays of the chain CR will have been picked up beforerthe car reaches the track section 2T, and theV switch controlling relay WR will remain deenergized-V when the car enters section 2T due to the fact Ythat all the

back contacts

53, 54, 55, 55 and V5l will be open. Under this condition the switch 4 will not` be moved and the carwill advance'oven the switch to the track IliA.4 If the speed of the car is too high so that it travels the track section IT before all the relaysof the chain are picked up, the switch controlling relay WR will become energized as soon as the car enters the section 2T and shunts the track relay 2TR. due to the fact that the pickup circuit for the relay IWR will be closed over the back contacts of the relays of the chain remaining deenergized. Under this condition, the motor M will be operated to move the switch to its reverse position and the car will advance over the switch to the track IDB. By introduction of manually controlled switches KI and K2 in the pickup circuit for the relay WR the time of operating switch 4 may be varied. For example, if the switch KI is opened a car moving slow enough in the section IT to permit the two relays IR and 2R to be picked up will cause the relay WR to remain deenergized and the switch 4 will not be operated. If the switch KI is closed and switch K2 is opened then a car moving slow enough in section IT to permit the rst four relays oi the chain to be picked up will prevent the relay WR from being energized and the switch 4 will not be operated.

It will be noted that once relay ITR is shunted, it can be reenergized only after a car has advanced into the section 3T and shunted the track relay 3TR to close the back contact 8 in the pickup circuit for relay ITR. The stick circuits for the energized relays of the chain will be supplied with energy as long as the relay ITR remains down and hence, the energizing circuit for the relay WR if closed will remain intact while the car occupies the section 2T. As the car passes from section 2T into the section 3T, the shunting of the track relay l3TR will open the iront contact II in the motor operating circuit and hence if relay WR has been picked up to reverse the switch 4, the motor M will not be operated to move the switch as long as the car remains in the section 3T. When the car vacates the section 3T, the relay WR will be deenergized and the motor M will be operated to restore the switch to its normal position automatically. To sum up the operation of the apparatus of Fig. l, a car travelling through a given track section iT at too high a speed so that it reaches the outgoing end oi the section in less than a predetermined time interval will cause the switch 4 to be automatically set in a position to advance the car to the track IDB. Should a-car move slow enough as it travels the predetermined track section IT so that it consumes more than a predetermined time interval before it reaches the outgoing end of the section, the switch 4 will remain in its normal position and the car will move to the track IDA. At such time as the switch has been reversed to move the car to the track IDB, the vacating of the track section 3T causes the apparatus to automatically restore the switch to its normal position.

Many applications for the apparatus of Fig. 1 will naturally suggest themselves to those skilled in the art. For example, at hump or scale tracks, a car moving on the scale track (section IT) at too high a speed to permit weighing and classification of the car will automaticallycause switch f3 to be reversed to direct that car to an emergency track where it can be later brought back and again pushed over the scales. Cars moving over the scales slow enough to be properly weighed and classied will pass over the switch 4 in its normal position and move to the usual classification yard (track IDA).

Referring to Fig. 2, the same principle of control is applied to the operation of a highway crossing signal. The traffic rails 2 and 3 of a stretch of railway over which trahie normally moves in the direction indicated by an arrow are intersected by a highway indicated by the reference character H. At the intersection there is located a highway crossing signal S. 'Ihis signal S may be of any of the usual type of highway crossing signals and is here illustrated as an audible signal in the form of an electric bell. It will be understood, however, that my invention is not limited to any specic form of highway crossing signal but may be any standard type in general use. The immediate operation of the signal S is governed by a controlling relay HR which when energized to close its front contact 63 completes a simple operating circuit for the signal S.

The traiiic rails 2 and 3 oi Fig. 2 are divided by the usual insulated rail joints into five consecutive track sections designated by the reference characters IT, 2T, 3T, 4T and 5T and which sections are traversed in the order named by a train as it approaches the highway when mov-- ing in the normal direction of traic. Each track section is provided with the usual track circuit comprising a track battery 5 and a track relay R with an exponent corresponding to the track section. The control of the track relay ETR departs `from the usual custom in that it is normally held energized over a stick circuit that includes its own front contact 6I, and is provided with a pickup circuit that includes the front contact 52 of the track relay ITR as will be readily understood by an inspection of Fig. 2. The function of this control provided for the relay 2TR will appear when the operation of the apparatus of Fig. 2 is described.

Associated with the track section IT is a time measuring equipment comprising a flasher relay NF and a relay chain CR. The ilasher relay NF is preferably similar to the flasher relay of Fig. 1 and is normally inactive. At such time as the track relay I TR is shunted and the track relay 2TR remains picked up, a shunt path is formed around the winding 22 of relay NF, and which includes the back contact 25 of relay ITR and a front contact 'i6 of the relay 2TR. It follows that as long as the track section IT is occupied and the track section 2T is unoccupied, the flasher relay NF is active to alternately shift the armature 24 between the right-hand contact 35 and the left-hand contact 34 at the rate oi thirty times per l minute. It will be understood, of course, that my invention is not limited to any specific rate of operation of the flasher relay and its rate may be made to suit specic locations. The alternate operation of the armature 24 serves to successively close the pickup circuits for the successive relays of the chain CR in the same manner as described for Fig. l and it is deemed unnecessary to repeat this operation in detail. It is to be noted that the stick circuit for each of the relays of the chain of Fig. 2 receives energy over a front contact 55 of the track relay 5TH, and a line wire G5. For example, the stick circuit for the relay I R extends from the B battery terminal over iront Contact 65, line wire 55, armature 2D of relay IR, transfer contact 35, Winding of relay ER and to the opposite battery terminal C. Consequently, the time consumed by a train in travelling the first track section iT is summed up by the number of relays of the chain CR energized at the time the train enters the section 2T and stops the operation of the ilasher relay NF. The relays of the chain picked up are retained energized over their stick cirrent source.

cuits. until the train advances to the last track section 5T and shunts the track relay 5TR.

The signal controlling relay HR. is provided with a plurality of diirerent energizing circuits. A rst energizing circuit for relay HR can be traced from the B terminal of the current source over back contact ll o1 relay ETR, wire Sl', back Contact 5S of relay 3R, line wire 59 and winding of relay ER to the opposite terminal C of the cur- A second energizing circuit extends from the B battery terminal over back contact 1Q of the relay ETR, wire 1l, back contact 'l2 of ren lay 5R and thence as before traced. A third energizing circuit extends from the B terminal of the current source over back contact 'i3 of the relay unoccupied and that a train moving in the nor-I mal direction oi traino is approaching the highway lf'i at a relatively high rate of speed, the train first enters the track section lT and shunts the track relay ETR to start the operation of the flasher relay NF. While the train occupies the section iT and before it enters the section 2T, the flasher relay NF is active to successively energize the relays of the chain in step with the alternate movement ci the armature 2li. YThe shunting oi the track relay ETR opens the operating circuit for the relay NF and operation of that relayris stopped with the armature 24 assuming its normal right-hand position. The time required for thisV train to travel the section ITV is summed up by the number of relays of the chain energized, Yand hence, ir the speed is relatively high so that the relay 3R is not picked up before the train enters the section T-the first energizing circuit for the relay HR is completed as soon as the relay ETR is shunted. It Vfollows thatrfor a relatively high speed train the highway crossing signal S is operated to warn highway users all the time the train is advancing

through'sections

2T, 3T, dT and 5T. Next, I shallassume that the train advancesV through the section IT Y at a somewhat lower speed, and that the relays ER, 2R and 3R are Vpicked up before the train enters the section ZT. Under this condition, the shunting of the track relay ZTR does not cornplete the first energizing circuit for relay HR due to the fact that the back contact (i8 of relay 3R is open, and hence the signal S is not operated during the tin-ie the train occupies the section 2T. When this train has advanced to the section 3T, the shunting of the track relay STR completes the second energizing circuit for the relay HR inasmuch as the back contact 'l2 of relay 4R is closed. It follows that for this train travelling at a somewhat lower speed, the signal S is operated during the time the train occupies the sections 3T, iT and 5T. Y Again, let us assumeV that the Vtrain is travelling at only a medium speed and the time it consumes in the sectionlT is sufcient to permitthe rst fourrelays of the chain Vto up before the train'shunts the track rethird energizing circuit for relay HR is completed and hence the signal S is operated during the time this train travelling at a medium speed occupies the two track sections 4T and 5T.V In the event the train approaching theintersection is travelling 5 at a relatively low speed and the time it consumes in the iirst section IT is suflicient to permit the complete chain of relays to be picked up, neither the first, second nor third energizing circuit for the relay HR is closed, and hence that relay is 10 not energized and the signal S is not operated Vuntil the train enters the section 5T.

It was previously pointed out that the'st-ick circuits for the relays of the chain CR, receive current over the front contact E5 of the track relay l5 ETR and, consequently, as soon as a train enters the iinal section 5T, all the energized relays of the chain are released and restored to their normal deenergized position.

1t is clear that knowing the maximum speed 20 for trains over theY stretch of track of Fig. 2, proper lengths for the various track sections can be selected so that the distance from the intersection at which the warning signal is set into operation will be so varied in accordance with 25 the speed of the train that approximately a uniform period of warning will be provided for a'll trains. it will be understood, of course, that the length of the Vtrack section IT and the time equipment are so proportioned and 'adjusted as 30 to select the proper point at which to start operation of the highway signal S. The control-Y lng relay HR of Fig. 2 may be of the interlocking type in which the first operating portion energized prevents full'operation of the second en- 35 ergized'portion, and the operating circuit of sig- .l S controlled in such a manner as to avoid operation of the signal when the stretch of railway is traversed by a train moving against the normal direction of traic. A train moving 40 against traffic will shunt the track relay ZTR before the track relay TR is shunted and relay ETR will not be reenergized until the train vacates thersectionY iT and relay ETR is picked up. vRelay QTR being held down during the time the 45 train moving against traine occupies the section iT, the asher relay NF remains inactive as this train moves away from the intersection.

`Referring to Fig. 3, the

trailic rails

2 and 3 of a stretch of single track railway are inter- 50 sected by a highway H at which there is located a highway crossing signalS. The traffic rails to the left of the highway H are divided into the track sections lT, 2T, 3T, 5T and 5T in a manner similar to that of Fig. 2. to the right of the highway H are divided into a similar set of track sections as designated by the

reference characters

6T, 1T, 8T, 9T and EST. In order to simplify the description I shall refer to a; train moving from the left to the right 60 in Fig as an eastbound train and a train mov- Y ing from the rightA to the left as a westbound train. For clarity certain of the contacts of the relays of the chaingCR are located in Fig. 3 remote from the winding of the relay. In all 65 such instances reference character of the relay is located just above thev Contact and the contact is further identified by a speciiic reference character.

YThe immediate control of the signal Siis obtained by an interlocking relay HRI, the two windings "ill and 19 of which are controlled'by traido to the left and right of the highway-H, Y respectively, as will shortly appear. A timing equipment'comprising a ilasher relaynNF and 75 The traic rails 55 a relay chain CR similar to the corresponding equipment for Figs. l and 2 is controlled by both the measuring track sections IT and IUT. At such time as the track relay ITR is down and the track relay ETR remains picked up, a shunt path is formed around the winding 22 of relay NF from the B terminal of the current source over front contact 'I9 of relay 'iTR, back contact 25 of relay iTR, line wire 89, front contact 8l of interlocking relay right-hand contact f armature 23 and to the center winding connection of the relay NF. Again, at such time as the track relay IElTR is down and the track relay STR remains picked up a shunt path is formed around the winding 22 from the B battery terminal over front Contact ii?. of relay 9TR, back contact 83 of relay IIlTR, line wire 84, front contact 85 oi interlocking relay HRI and thence as before traced. It follows that the flasher relay NF is operated during the interval an eastbound train is passing over the track section IT, and also during the interval a westbound train is passing over the track section IOT. A westbound train occupying the section IT is not effective to operate relay NF due to the fact that the winding 'IS of the interlocking relay HRI is not energized at this time to close the front contact Si as will appear hereinafter. Due to the fait that the winding '119 of the interlocking relay HRI is held deenergized while an eastbound train occupies the section IElT, that train is ineffective to operate the iiasher relay NF. Operation of the flasher relay NF is effective to pick up the successive relays of the chain CR in a manner similar to that described for Fig. 1. For example, with an eastbound train in the section iT the iirst swing of the armature 24 to the left completes the pickup circuit for relay IR, and which circuit includes a front contact 86 of relay ZTR, back contact 81 of relay ITR, line wire S9, left-hand contact of armature 24, back contact 3i of relay IR, transfer contact 39, and winding of relay IR to the opposite terminal of the current source. With relay IR picked which in this instance includes a front contact up, it is held energized by its stick circuit and 99 of the track relay GTR, front contact Sl) of the track relay TR, and its own armature 29 as will be readily understood by an inspection of Fig. 3. From this point on, the successive operation of the armature 24 will successively energize the relays of the chain over the circuits just traced with the result that the time required for an eastbound train to travel the track section IT is summed up by the number of relays of the chain energized. In a similar manner, the relays of the chain are counted off as a westbound train occupies the section I9T. In this latter case, the pickup circuit for energizing the relays of the chain include the front contact 9i of relay 9TR, back contact 92 of relay IUTR, line wire 93 to the armature 24 and thence as before traced as will be readily understood from Fig. 3. The stick circuit for retaining the relays energized is the same for the westbound train as for the eastbound train. It follows that the timing equipment comprising the relay NF and the relay chain CR functions for an eastbound train approaching the highway H to determine the time that train consumes in passing over the section IT, and functions in a like manner to determine the time a westbound train approaching the highway H consumes in passing over the section I9T.

Assuming all the track sections to be unoccupied and that an eastbound train is approaching the intersection, this train will cause the timing equipment to measure the time it consumes in passing over the section IT. In the event the train is travelling at a relatively high speed and chain relay 3R is not picked up before the train enters the section 2T, the signal S is set into operation at once. The releasing of the track relay TR opens the holding circuit for the winding 'I8 of the interlocking relay HR, and the releasing of that winding closes at the back contact I I8 the operating circuit for the signal S. The holding circuit for winding 'I8 normally extends from the terminal B of the current source over

front contacts

94, 95 and 96 of the track relays 2TR, 3TR and ATR, respectively, front contact 9i' controlled by winding IB, front contact 98 Vcontrolled by relay STR and Winding 18 to the opposite terminal C of the current source. It follows that winding 'I8 will remain deenergized and the signal S operated While this eastbound train passes over the

sections

2T, 3T, 4T and 5T. As soon as the rear of the train vacates the section 5T, the winding 'I8 is reenergized by current supplied over a pickup circuit that includes the

front contacts

94, 95 and 96 and thence extends over line wire I ill, front contact I of relay ITR, line wire 99, front contact 98 of relay 5 TR and Winding i9 to the C battery terminal. Although the winding 'I9 of the interlocking relay will be deenergized while the eastbound train moves away from the highway H through the sections shown at the'right of the highway, the interlocking feature of relay HRI will prevent the closing of the back contact III controlled by winding 'I9 and signal S will not be operated. Assuming a somewhat lower speed for the eastbound train as it approaches the highway intersection and that the chain relay 3R is picked up before the track relay 2TR isshunted, the Winding 'I8 will receive current from the B terminal of the current source over front contact IIIl of relay 3R and thence over the holding circuit above traced. Under this condition, the winding'IS will remain energized until the eastbound train enters the section 3T and track relay 3TR is released. The control of the interlocking relay HRI as this train moves away from the highway H will be the same as for the rst eastbound train. In the event the eastbound train is moving only at a medium speed and chain relay 4R is picked up while the train is passing over section IT, the winding 'I8 will receive current from the B terminal of the current source over front contacts II Il and III of

relays

3R and 4R, respectively, and the holding circuit described above. Consequently, the signal S is operated for this eastbound train travelling at medium speed only during the time it occupies the

sections

4T and 5T. Again, if the eastbound train is travelling at a relatively low speed and the ve relays of the chain CR are all picked up, the winding 'I8 receives current Vfrom the B terminal of the current source over front contacts IIO, III and II2 of the relay chain and the holding circuit described above With the result that the signal S will be operated only while the train occupies the track section 5T.

Winding I9 of the relay HRI is provided with a normal energizing stick circuit extending from B battery terminal overvfront contacts I92, ID3 and |94 of track relays STR, STR and 'ITR, respectively, its own front contact |05, front contact |06 of track relay GTR and winding 'I9 to the C battery terminal. The pickup circuit for winding 'I9 extends Vfrom B battery terminal over the same circuit up to front contact |04 and thence over line wire |09, front contact |08 of relay ISTR, line wire I'I, front contact IUS and winding 'I9 to the C battery terminal. It is clear therefore that the apparatus of Fig. 3 will function to control the normal stick circuit for winding 19 Vin response to westbound trains in the same manner as described for eastbound trains controlling the winding I8 of relay HRI. The ront contacts IIS, H4 and H5 of the relays iR, 4R and 5R, respectively, determine the track section at which the winding 'I9 becomes deenergized to close the operating circuit for theV` Vsignal S. Although the winding 'IB will be de energized while a Westbound train moves away from the highway I-I, the interlocking feature of the relay HRI will prevent the closing of the back contact IIB controlled by the winding '18.

The utility of railway traffic controlling apparatus such as here disclosed is that it provides a flexible time measuring device which will remain accurate notwithstanding a relatively large variation of voltage of the current source, and which will automatically function to operate a mechanism in response to a car or train passing over a given track section at a speed above a given value. y

Although I have herein shown and described Aonly three forms 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.

I-Iaving thus described my invention, What I claim is:

1.V In combination, a rst and a second track section to be successively traversed by a car, a flasher relay, means to operate said relay as a car travels said first track section, a chain of relays normally deenergized, means to successively energize the relays of said chain in step with the operation of said flasher relay, a stick circuit for each relay of the chain adapted to retain its relay energized when once picked up, an operating mechanism normally inactive, control means rendered effective as the car enters said second track section to operate said mechanism, and means governed by the relay chain to render the control means ineffective when a predetermined number of relays of said chain are energized. i

2. In combination, a rst and a second track section to be successively traversed by a car, a flasher relay, means to operate said relay as a car travels said iirst track section, a chain of relays normally deenergized, means to successively energize the relays of said chain in step with the operation of said flasher relay, a stick circuit for eachrelay of the chain adapted to retain its relay energized when once picked up, an operating mechanism normally inactive, means governed by said relay chain rendered effective as the car enters said second track section to operate said mechanism unless a predetermined number of said relays are energized, and means governed by said car for subsequently opening said stick circuits.

3. In combination, an operating mechanism located at one point along a railway and normally inactive, a flasher relay, means to set said flasher relay into operation as a car passes a iirst given point in approaching said one point, a chain of relays normally deenergized, means to successively energize theV relays of said chain in step with the operation of said flasher relay, means to stop the operation of the flasher relay as the car passesra second point in approaching said one point, control means effective as the car passes said second given point to render the operating 5 mechanism active, and means governed by the relay chain to render the control means ineffective when a predetermined number of the relays of said chain are energized.

4. In combination, an operating mechanismV located at one point along a railway and normally inactive, a flasher relay, means to set said asher relay into operation as a car passes a nrst given point as it approaches said one point, a chain of relays normally deenergized, means to successively energize the relays of said chain in step with the operation of said flasher relay, a stick circuit for each relay of the chain, means to stop the operation of the iiasher relay as the car passes a second given point in approaching said one point, and means governed .by said relay chain effective as the car passes said second given point to render the operating mechanism active unless a predetermined number of the relays of said chain are energized.

5. In combination, an operating mechanism located at one point along a railway and normally inactive, a flasher relay, means to set said flasher relay into operation as a car passes a first given point in approaching said one point, a chain of relays normally deenergized, means 'to successively energize the relays of said chain in step with the operation of said ilasher relay, means to stop the operation of the flasher relay as the carV passes a second point in approaching said one point, control means eiiective as the car passes said second given point to render the operating means active, and means governed by the relay chain to render said control means ineffective when and only when a predetermined number of 40 relays of said chain are energized.

6. In combination, an operating mechanism located at one point along a railway and normally inactive, a first and a secondV track section to be successively traversed as a car approaches said one point, a first track relay for said rst section and a second trackrelay for said second track section, a flasher relay, an operating circuit for said flasher relay including a front contact of the second track relay and a back contact of the first track relay, a chain of relays normally deenergized, a pickup circuit for each relay of said chain and each including an armature of the flasher relay and a front contact of the preceding reiay of the chain whereby said relays are energized successively in step with the alternate operation of said armature, a stick circuit for each relay to retain its relay energized irrespective of said flasher relay, and an operating circuit for said operating mechanism including a back contact of given relay of said chain and a back contact of the second track relay whereby said mechanism is rendered active in response to a car entering the second track section uniess said given relay of said chain is picked up. 7. In combination, an operating mechanism located at one point along a railway and normally inactive, a first and a second track section to be successively traversed by a car approaching said one point, a first track relay for said rst section and a second track relay for said second section, a flasher relay having a predetermined frequency of operation, an operating circuit including a front contact of the second track relay and a back contact of the rst track. relay for opi erating said iiasher relay, a chain of relays normally deenergized, a pickup circuit for each relay of the chain and each including an armature of the flasher relay and a front contact of the preceding relay of the chain whereby said relays are energized successively ,in step with the mternate operation of said armature, a stick circuit for each relay to retain its relay energized irrespective of said flasher relay, and an operating circuit including a back contact of the second track relay and a back contact of the final of said chain for the operating mechanism whereby said mechanism is rendered active when a car passes over the first track section at too high a speed.

8. In combination, a railway switch having a rst and a second position and normally occupying its rst position, operating means for moving the switch, a rst and a second track section traversed by a car in approaching the switch, a asher relay, means for operating said relay as a car travels the first track section, a chain of relays normally deenergized, means to successively energize the relays of the chain in step with the operation of said iiasher relay, control means governed by the relay chain effective to control the operating means to move the switch as the car enters said second track section, and means governed by the relay chain to render the control means ineffective when aY predetermined number of the relays of said chain are energized.

9. In combination, a railway switch having a first and a second position and normally occupying its first position, operating means for moving the switch, a first and a second track section traversed by a car in approaching the switch, a flasher relay, means for operating said relay as a car travels the first track section, a chain of relays normally deenergized, means to successively energize the relays of the chain in step with the operation of said flasher relay, control means eiective as a car enters said second track section to control the operating means to move the switch to the second position, and means governed by the relay chain effective when and only vhen a predetermined number or" relays of said chain are energized to render said control means ineffective.

l0. In combination, a stretch of railway track intersect-ed by a highway, a highway crossing signal located at the intersection, controlling means for setting the signal into operation when a train approaching the intersection reaches a xed point, a flasher relay, means for operating said relay as a train approaches said iixed point, a normally deenergized relay chain, means for energizing the relays of said chain successively in step with the operation of said flasher relay, a

l stick circuit for each relay of the chain, means controlled by said relay chain for rendering the controlling means ineifective when a predetermined number of relays are energized before the train reaches said fixed point, and means for ,annulling the control of said relay chain when the train reaches a second fixed point nearer to the intersection.

11. In combination, a stretch of railway track intersected by .a highway, a highway crossing signal located at the intersection; a rst, a second and a third iiXed point which a train successively passes as it approaches the intersection; controlling means ior setting the signal into operation when atrain reaches said first fixed point, a flasher relay, means for operating said relay as a train approaches said first fixed point, a normally deenergized relay chain, means for energizing the relays of said chain successively in step with the operation of the flasher relay, a stick circuit for each relay of the chain, means controlled by said relay chain for rendering the controlling means ineffective when a predetermined number of relays are picked up before the train reaches said first fixed point, and means for annulling the control of said relay chain when the train reaches either the second or the third Xed point depending upon the number of relays of the chain energized.

12. In combination, a stretch of railway track intersected by a highway, a highway crossing signal located at the intersection; a iirst, .a second and a third track section which a train successively travels as it approaches the intersection; a flasher relay, means for operating said relayas a train travels the rst track section, a chain of relays normally deenergized, means for energizing the relays of the chain successively in step with the operation of said flasher relay, a stick circuit for each relay of the chain for retaining its relay energized irrespective of the flasher relay, controlling means for setting said signal into operation when a train enters said second track section, means controlledby said relay chain in response to a predetermined number of said relays being held energized to render said controlling means ineflective, and means responsive to the train entering the third track section for annulling the control of said relay chain.

13. In combination, a stretch of single track railway intersected by a highway, a highway crossing signal located at the intersection, an interlocking relay, a circuit controlled by said relay for operating the signal, a first and a second track section travelled in the order named by an eastbound train approaching the intersection, a third and a fourth track section travelled in the order named by a westbound train approaching the intersection, a flasher relay, means to operate the liasher relay in response to an eastbound train passing over the first track section and in response to` a westbound train passing over the third track section, a relay chain normally deenergized, means to energize the relays of said chain successively in step with the operation of said flasher relay, and means governed jointly by said relay chain and the second and the fourth track sections for controlling said interlocking relay.

14. In combination, a stretch of single track railway intersected by a highway, a highway crossing signal located at the intersection, an interlocking relay having a rst and a second magnet, a circuit controlled by said'relay for operating the signal, a plurality of consecutive eas*- bound track sections to be travelled by an eastbound train approaching the intersection, a pl".- rality of consecutive westbound track sections to be travelled by a westbound train .approaching the intersection, a flasher relay, means to operate the flasher relay as an eastbound train passes over the most remote eastbound section and as a westbound train passes over the most remote westbound section, a relay chain normally deenergized, means to energize the relays of the chain successively in step with the operation of the iiasher relay, means controlled by the energized relays of the chain in cooperation with the eastbound track sections to govern the iirst magnet of the interlocking relay, said control being effective to select the section at which to start operation of the signal in accordance with the speed of the eastbound train so as to give approximately a like period of operation for all trains, and

means controlled bythe energized relays of the. chain in cooperation with the Vwestbound track sections to govern the second magnet of the interlocking relay, said control being effective to select the section at which to start operation of the signal in accordance with the speed of the westbound train so as to give approximately a` like period of operation for all trains.

15. In combination, a stretch oi single track railway intersected by a highway, a highway crossing signal located at the intersection, an interlocking relay having a first anda second magnet, a circuit controlled by said relay for operating the signal, a plurality of consecutive eastbound track sections to be travelled by an eastbound train approaching the intersection, a plurality of consecutive westbound track sections to be travelled by a Westbound train approaching the intersection, a time measuring device normally inactive, operating means responsive to an eastbound train passing over the most remote eastbound track section and to a westbound train passing over the most remote westbound track section to render the time measuring device active, a rst control means governed by said device cooperation with the eastbound sections to control the rst magnet of the interlocking relay for governing the operation of the signal in accordance with the speed of eastbound trains, a second control means governed by said device in cooperation with' the westbound sections to control the second magnet of the interlocking relay for governing the operation of the signal inA accordance with the speed of westbound trains, and means controlled by the interlockingrelay for rendering the operating means ineiective as a westbound train passes over the eastbound sections and as an eastbound train passes over the westbound sections. 4

16. In combination, a section of railway track, a flasher relay, an operating circuit controlled by a car to operate said relay while the car traverses said section, a chain of relays normally deenergized, means including an armature of said flasher relay to successively energize the relays of said chain in response to operation of said flasher relay, a stick circuit for each relay of the chain to retain that relay energized irrespective of said flasher relay, a traic governing mechanism normally inactive, and circuit means controlled by the relay chain to effect operation of said mechanisrn in accordance with the number of relays picked up in response to the car traversing said section. l

i7. In combination, a railway switch having a rst and a second position, operating means for moving the switch, a flasher relay, means controlled by a car for operating said relay as the car travels a given track section in approachingY the switch, a chain of relays normally deenergized, means to successively energize the relays of the chain in response to operation of the fiasher relay, and control means controlled jointly by the car when it has traveled said section and by said relay7 chain for governing the operating means.

PAUL H. CRAGO.