[1]Patented Apr. 28, 1942 21281 046 UNITED STATES PATENT OFFICE 2,281,046 RAILWAY TRAFFIC CONTROLLING APPARATUS Easton E. Parr!H. Swissvale, Pa., assignor to The Union Switch & Signal Company, Swissvale, Pa., a corporation of Pennsylvania Application March 25, 1941, Serial No. 385,040 7 Claims. My invention relates to railway traffic controlling apparatus, and m6re particularly to train governing apparatus controlled accordin.@ to the speed at which a train approaches a designated locality. Vv'hen a train app,.,oaches the end of a track within station limits, or apprbaches the dead end of a track, a speed restriction for the train is required in order to avoid p6ssible overrunning of the track limits. Likewise at grades, con- @10 gested territory and like locations, it is desirable that the speed of a train passing through a track section in the approach to such a locati6n be at or below a predetermined value. In other words, it is desirable. that at least a predeter- @.15 mined period of time be consumed by a train in passing through a track section in the approach to a track hazard in order that a proceed condition of the signaling devices governing the movement of the train at such track hazard. be effected ' Accordingly, a feature of my invention is the provision of railway traffic controlling apparatus incorporating novel and improved means for controlling train governing devices according to the;"'3 speed at which a train approaches a designated station or location. Another feature of my invention is the provision of novel and improved means for reqliiring that a train consume a predetermined period of I" 'I@ time or more in moving through a given track section in order that a signaling device goveming the entrance of the train into another track section in advance be operated to a proceed @, : position. Again a feature of my invention is the provision of novel and inexpensive railway traffic contfolling apparatus of the type here contemplated for operating a time element relay when a train occupies the rear track section of two successive i4 sections and for including contacts of such time eiement relay in the operating circuits of an automatic train stbp and signal associated with the advance section of such two sections, and the usual control relays now provided are not re- @4i quired. Such time element relay is used to determine that a train consumes at least a predetermined period of time in traversing the rear track section. Still another feature of my invention is the j provision of novel and inexpensive means for railway traffic controlling apparatus of the type here involved wherewith a signal governing traffic in the rear section of two sections can be operated to a proceed position only if the signal ,5 @ 5 (Cl. 246-39) g6verning traffic in the advance section of the two sections displays a stop indication. The above features, as well as other advantages of my inventign wwch will appear as the speciflcation progresses, are attained according to my invention by providing a time element relay having a check c6ntact closed 6nly when the relay occupies its ira'tial position and front and back contacts which are operated after the relay has be6n energized for a preselected tiine interval, circuit means for energizing such relay, and train governing devices governed by the relay. Such circuit ineans is controlled by the track relays of each of two successive track secti6ns and by an automatic train stop associated with the a,dvance section of the two track sections. The operating circuit of the automatic train stbp and the operating circuit of a signal for the advance section include front contacts of the time element relay. A signal for the rear section of such two track sections is controlled over the check contact of the time element relay and hence the signal for the adva'nee@ si@ction displays stop in order for the signal of the rear section to display a proceed position. I shall describe one form of apparatus embodying by invention and shall then point out the novel features thereof in claims. The accompanyl'-ng drawing is a diagrammatic view showing one form of apparatus embodying my invention v,,hen used for governing an aut6matic signal and an automatic train stop for a stretch of railway approaching a track hazard such as, for example, a station or a descending grade or a congested territory. Referring to the drawing@ the reference characters la and lb designate the track rails of a stretch of railivay and whic rai s are forme by the usual insulated rail joints into consecutive track sections of a signal system and of @which track sections only three sections A-B, B-C and C-D are shown since these are sufficient for a full understanding of my invention. These track sections may be those in the apProach to a station or to a location of congested traffic or to a descending grade. The significant point about such stretch of railway track is that restricted speed is required for a train moving through these sections in the normal direction of travel as indicated by an arrow. Each section is provided with a signal designated by the reference character S, plus a suffix corresponding to the location of the signal. These signals may be 6f any one of the several types commonly used. In the present em-
[2]bodiment of my invention these signals are color light signals each of which is capable of displaying a yellow lamp Y for a proceed indication and a red lamp R for a stop indication. Automatic train stops TB and TC are located at the entrance of sections B-C and C-D, respectively. These automatic train stops may be any one of several well-known types ard are shown by the usual conventional symbol. Such train stops may be, for example, of the t,%roposition type covered by Letters Patent of tle Tfnited States No. 1,775,811, granted September 16, 1930, to John P. Coleman, for Railway traffic controlling apparatus. It is sufficient for this a.pplicatio,p- to point out that the trackway element of such train stop is operated to a vertical or stop position and to a horizontal or clear position. It is preferably moved t6 its stop Position by a biasing spring or by gravity or by both, and to its clear position by a suitable power mechanism controlled by an electric circuit. The function of the trackway element for such train stop is, to cooperate with a train-carried element, the arrangement being such that the train-carried element is effective to cause the shutting off of the propelling power or the application of the train brakes, or both, if the traiii should attempt to pass the trip arm of the trackway element when such trip arm is raised to its stop position to engage the train-carried element. When the trip arm is lowered to its clear position, thetrain-carried element is not engaged as the train passes the trip arm, and the train is uiiimpeded ' Each train stop TB and TC is provided with a circuit controller which is operatively connected therewith as indicated by dotted lines 4 and 5, respectively. Thus contacts 61 7 and 8 of a circuit controller are operated 'to the positions illustrated by the solj:d lines in the drawing when the train stop TB is set at its stbp position, that is to the positio'n sho-,am in the d@awing, and are 6perated to the positions illustrated by dotted lines when the train stop is set at the clear position. In like fashion contacts 9, IO and I I are operated to the positions illustrated by the solid lines in the drawing when train stop TC is set at the stop position and are operated to the positions illustrated by the d6tted lines in the drawing when the train stop TCI is set at the clear position. Each track section A-B, B-C an.d C-D is provided with a track circuit including a curre-nt source connected across the rails at one end of the section and a track relgy connected P.cross tl-ie rails at the other end of the section. In the present case alternating current track circuits are provided, the track relay being indicated 'by the reference character TR plus a prefly corresponding to the location of the relay and each current source being a transformer indicated by the reference character T plus a prefix correspondi-ng to its location. The operating circuits for signal SA are controlled by a sig -nal control relay SAI-I, the operating circuits for signal SB apd its associated train stop TB are governed by 9, time element relay BTE, and the operatin_p, circuits of signal SC and its associated tra'm stop TC are governed bv a time element relay CTE. Relay SAH is an alternating current'relay of the usual type. Time element relays BTE and CTE are pref.erably alilce and may be any one of the several types well known to the art and may be, for example altemating elrrent time element I 2,2811046 relays covered by Uiiited States Letters Patent No. 1,272,972, granted July 16, 1918, to L. V. Lewis, for Circuit controllers. Looking at tirne element relay BTE, when the relay is deenergized@ it is biased to an initial position wliere a check contact 12 is closed and its contact members 13, 19, 15, 16 and 17 are in engagement with back contacts, the back coiltacts 18 and 19 associated with contact mem e@@s 6 10 atid 17, respectively, being the only oiies shown in the drawing. When an operating winding 20 of the relay is energized, check contact 12 is immediately opened and remains open until such time as winding 20 is deenergized and the contact 15 mechanism of the relay again assumes ti-ie initial position. Vi7hen winding 20 is energized for a preselected time interval of say, for example, 25 seconds, the contact members 13 to 17, inclusive, are moved from engag--Ment with their 2( respective back contacts to engagement with respective front contacts of which front contacts only the front contacts 21, 22 and 23 associated with contact members 13, 14 and 15, respectively, are shown in the drawing. As stated 25 he@einbefore, time element relay CTE is preferably similar to BTE and further description of relay CTE is not required. Signal control relay S-A!T- w.ien picked up closiiig fro-rit contact 24, conipletes an obvious oper30 ating ci,rcuit for ti-i-e proceed lam-0 Y of signal SA ar-d wheil relay SA-H is releasea e'losing back contact 25 an obvious operating circait is completed for stop lamp R of signal SA these 6perating ei-rcuits being connected to any convenient 35 source of current, such as a source of alternating currep-t Whose terzrinals are indicated at BX and CY-. Relay SAH is in turn energized over a circuit including terrnitia! EX of the current source, check contact 12 of ti-i.,ne eler.,ient relay BTE, 40 back contact 17-19 of relay B--E, front contact 26 of track relay ATR, winding of relay SAH and terminal CX (>f the current source. 'I@M4-1 element relay BTE is energi_zed by a eircuit that can be traced from terminal BX over back con4.5 tact 23-'r7 of relay CTE, check contact 29 of relay CTE, front contacts 30 and 31 of track relays CTR and BTR, respectively', back conta,6t 32 of track relay ATR, contact 6 of the controller for automatic train stop TB closed at the ston 50 -poqition, and vinding 20 of relay BTE to terminal CX. Relay BTE when energized for its preselect(,,d o ' i ' aerating Period closes fror@t contact 13-21, and ceripletes a stick circuit path foi by-passipg thisenergizing circuit aroiind contact 55 6 of train stop T@B. In the case train stop @ TB is set at its stop position and relay BTE is deenergized to o@-cLi.py its initial Position, an operating circuit is fo3.,w-ed ilicluding terminal BX, back contact 16-18 of relay BTE and co-ntact 60 8 of the controller of tro-in st6p TB iii multiple, stop larnp R of signal SB and terminal CX, and signal SB is operated as required to display a stop indication. Train stop T]3 is provided with a sli-nple operating circuit including front r e elemeiit relay BTE in a5 contact 14-22 of tim multiple with back contact 50 of track relay BTR. Wi-th relay BTE operated to close its front cont,,tct @5-23 and train sto-o TB operated to its clear Position to cl(@,S-- contact 7, aii operating 7o circuit is formed from terminal BX oirer front contact 15-23, contact 7, and lamp Y to terminal CX, and sigiial SB is O-Derated as required t6 display a proceed indication. Tir-.,Ie element relay CTE is energized over@ a 75 circuit includin back conelact 3 of track r I 9 3 e a3@
[3]2,281,046 3 BTR, front contact 34 of track relay CTR and contact 9 of the controller of train stop TC in its stop position. Relay CTE when thus energized for a preselected time interval to close front contact 35-36 completes a stick circuit path which by-passes the energizing circuit for the relay around contact 9 of the circuit controller of the automatic train stop TC. When relay CTE is set at its initial position to close back contact 37-38, or when train stop TC is set at its stop position to close contact I 1, an operating circuit is formed for lamp R of signal SC as will be readily understood from an inspection of the drawing, contacts 37-38 and I I being included in the circuit in multiple. The operating circuit for train stop TC includes front contact 39-40 of time element relay CTE in multiple ,vith back contact 51 of track relay CTR. Also a proceed operating circuit for signal SC can be traced from terminal BX over front contact 41- 42 Of relay CTE, contact 10 of the controller for train stop TC closed at the clear position, lamp Y of signal SC and to terminal CX. Normally, that is, when sections A-B, B-C and C-D are unoccupied, the track relays are all picked up, time element relays BTE and CTE are deenergized causing the respective signals SB and SC to display the stop indication and the i-espective train stops TB and TC to be set at the stop position, and signal control relay SAH is picked up to operate signal SA as required to display its proceedindication. Since relay SAH is energized over a circuit including check contact 12 and back contact 17-19 of relay BTE, it is to be noted that signal SB is operated to display its stop indication and train stop T'13 is operated to its stop position before signal SA can be operated to display its proceed indication. In the case a train moving in the normal direction of traffic enters section A-B to shunt track relay ATR, the energizing circuit for time element relay BTE is closed and that relay is opera-ted to at once open check contact 12 and then to move its contact members 13 to 17, inclusive, at the end of the operating period preselected for that relay. When relay BTE is operated to close its frbnt contacts the operating circuit for train stop TB is closed at front contact 14-22 and the tra,in stod is lowered to its clear position, relay BTE being retained energized over its stick circuit path after contact 6 is opened at the clear position of the stop. It is to be noted that the operating circuit for stop lamp R for signal SB is retained closed at contact member 8 of train stop TB after relay BTE is operated until the train stop is subsequently moved to its clear position. With time element relay BTE operated to close its front contact i 5-2 3 and train stop TB ope.rated to its clear position closing contact 7 of the corresponding circuit controller, the operating circuit for proceed lamp Y of signal B is closed and that lamp is illurninated to display a proceed indication. It follows that the train must consume a time interval at least equal to the operating time of time element relay BTE in traversing section A-B in order f6r it to receive a proceed signal at signal SB to enter section B-C, and in order to avert an automatic brake application as effected through train stop TB in the event the train enters the section B-C before the stop TB is moved to its clear position. In other words, the speed of the train must not exceed the prescribed average speed in traversing be that safe for the train to approach sections B-C and C-D due to the hazards associated with such sections. The train upon entering section B-C to shunt track relay BTR completes the energizing circuit for time element relay CTE and that relay is energized to at once open check contact 29 and then to move its contact meinbers to close front contacts at the end of the operating time pre10 selected for that relay. The shunting of track relay BTR opening front contact 31 deenergizes relay BTE and that relay is immediately released to its initial position causing signal SB to be operated to its stop position, and one path of 15 the operating circuit of the train stop TB to be opened, train stop TB being now retained at the clear position over the path of its operating circuit including back contact 50 of relay BTR. With relay CTE operated to close front contact 20 39-40, the train stop TC is operated to its clear position, relay CTE being retained energized over the stick circuit path subsequent to the train stop TC being lowered to the clear position. Train stop TC when operated to its clear position 25 closing contact 10 completes the operating circuit for proceed lamp Y of signal SC and signal SC is operated as required to display a proceed indication. Consequently the train must consume in section B-C a time interval at least 30 equal to the preselected operating time of relay CTE in order to receive a proceed indication at signal SC for entering section C-D and in order to avoid a brake application as effected by train stop TC. That is, the speed of the train m 35 section B-C must not exceed the prescribed average speed consistent with the track hazard of section C-D. The train upon entering section C-D shunts track relay CTU to open front contact 34 and 40 deenergize relay CTE which relay restores to its initial position where the operating circuit for proceed lamp Y of signal SC is opened and the circuit for lamp R of signal SC is closed causing signal SC to display a stop indication. Train 45 stop TC is now held at its clear position over the path of its operating circuit including back contact 51 of relay CTR. The train by vacating section C-D permits track relay CTR to be picked up and the apparatus is then restored to r)o its normal position. It is to be seen therefore that I have provided nbvel and improved means wherewith the operating circuits of a signal and of a trairl stop are completed over contacts of a time element relay 55 and the usual control relays for such signal and train stop -are not required. Also there is here provided improved means wherewith the speed of a train as it approaches a location of a track hazard is governed. Again, a proceed indication 60 of a signal for a track section in an approach to a track hazard is operated to display a proceed indication only when the signal and train stop for the section in advance are set at stop. It is to be noted that train stops TB and TC are re65 tained at the clear position when the respective track section is occupied in order that they may be cleared for trains moving against the normal direction of traffic. Although I have herein shown and described 70 only one form of railway traffic controlling 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 section A-B and which speed would of course 75 scope of my invention.
[4]4 ilaving tl-ius described my invention, what, I
