US2494959A

US2494959A - Railway traffic controlling apparatus for interlocked home signals

Info

Publication number: US2494959A
Application number: US680924A
Authority: US
Inventors: John R Myers
Original assignee: Union Switch and Signal Inc
Current assignee: Hitachi Rail STS USA Inc
Priority date: 1946-07-02
Filing date: 1946-07-02
Publication date: 1950-01-17
Anticipated expiration: 1967-01-17

Description

Jam 117 W559 Y J. R. MYER$ ZALWLEEQ RAILWAY TRAFFIC CONTROLLING APPARATUS FOR INTERLOCKED HOME SIGNALS Filed July 2, 1946 i INVENTOR- HIS'ATTGHZVEY Patented Jan. 17, 1950 RAILWAY TRAFFIC CONTROLLING APPA RATUS FOR INTERLOCKED HOME SIG- NALS John R. Myers, New York, N. Y., assignor to The Union Switch and Signal Company, Swissvale Pa., a corporation of Pennsylvania 7 Application July 2, 1946, Serial No. 680,924

My invention relates to railway traffic controlling apparatus, and more particularly, to apparatus for the control of interlocked home signals in a block signaling system of the overlap type including automatic train stops.

In signaling systems of this character, it is the practice to employ neutral home and distant relays for the control of the caution and proceed aspects of the signals, and to provide an additional relay for the control of the call-on aspect provided in connection with an interlocked home signal to permit a train to pass the signal when the track section in advance is occupied.

One object of my invention is to eliminate this additional relay, and to provide a system employing only one relay for controlling both the proceed aspect and the call-on aspect of the signal, but without causing undesired flashing of any of the signal lamps during a change from one aspect to another.

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

In the accompanying drawing, I have shown a track plan of a stretch of railway track containing a small interlocking plant comprising a track switch 5 and an interlocked home signal 2 for governing traffic movements over the switch, together with the circuits and apparatus arranged in accordance with my invention for controlling signal 2 and a mechanism 2V associated therewith for operating the trackway tripping member 2a of an automatic train stop. As shown, the tracks are divided into block sections IT, 21', etc.,

each equipped with a track circuit having a track relay lTR, ZTR, etc., normally energized by alternating current from a source the supply terminals of which are identified by the reference characters BX and CK.

To simplify the drawing the local source of current for energizing the various relays is identified by its terminals which are designated B and C, respectively.

Since they form no part of my invention, the circuits for controlling the track switch I are not shown, but the position and locked condition of the switch is reflected in the signal circuits by the provision of a normal switch indication relay lNWP and a reverse switch indication relay I RWP, each of which when energized manifests that the switch is closed and locked in a corresponding normal or reverse position.

Signal 2 is of the color light type comprising an upper signal unit 2A containing three lamps G, Y and R. and an illuminated number plate dis- 5 Claims. (Cl. 246-26) playing the signal number. These lamps are controlled in accordance with trafiic conditions by a home signal relay 2H and a distant signal relay 2D and also by a repeating relay ZVP of the train stop mechanism 2V. The lamps G, Y and R, of a similar signal unit 213 are controlled by relays 2H and WP and also by relays INWP and IRWP to designate the route governed by signal 2. A third signal unit 20 has a single lamp Y which serves as a call-on signal and is controlled by relay 2D and by a manually controllable stick relay 2008. The home relay 21-1 is controlled by a manually operable signal lever 2SG and by a stick relay ZHY controlled by the track relays ITR. and 4TB when switch I is normal or by relays ITR and GTR when switch I is reversed, sections IT and GT or 6T embracing the home control limits for signal 2. When relay 21-1 is energized relay 2D extends the control limits for signal 2 to include one or more sections beyond the next signal 4 or 6 in advance in the route established by switch I, the circuits for relay 21) including front contacts of relays 4H and AW when switch I is normal and the corresponding contacts of relays 6H and GVP when switch I is reversed. It is to be understood that these relays are controlled by track relays like relays 2H and 2VP, except that no lever control is provided and they are normally energized. The operation of relay 2D as a distant relay is not needed when relay 2H is released, and relay 2D is then enabled to serve as a call-on signal relay to control lamp Y of the lower signal unit 20, in accordance with a feature of my invention.

The operation of the apparatus of my invention under diifere'nt assumed conditions will now be described in detail. Assuming that switch l is normal, as shown, relay 2HY is energized over the circuit from terminal B at contact a of relay INWP extending over contacts a of relays 4TB, and ITR. through relay ZHY to terminal C at the normally closed contact a of lever 28G or at the front contact a of relay 2HY.

If now the operator reverses lever 28G, relay ZHY is held energized over the stick circuit including its contact a and relay 2H picks up over the circuit from terminal B at contact b of lever 23G, back contact a of relay ZCOS, contacts b of relay ZHY and mechanism 2V through relay 21-1 to terminal C, relay 2H completing a stick circuit at its own front contact a. Relay 2H completes a circuit at its contact b to energize mechanism 2V, which retracts the trip arm 2a and energizes its repeating relay ZVP. Relay ZVP then com- 55 pletes a circuit from terminal BX of the alternatwill therefore change from stop to caution to au-.

thorize a train to advance to signal 4, and if signa] 4 indicates caution or proceed,.relays 4H: and 4VP will be energized to complete a circuit from terminal B over their front contacts a, contact of relay iNWP, front contact" at .of relay 2H, through relay 2D to terminal (3', relay 2D be- 2V and relay 2V1, and if lever ZSG is placed in its normal position, relay ZHY will become energized when the train vacates sections IT and. 4T to restore the apparatus to the condition shown in the drawing.

When switch I- is reversed-so that relay IRWP is energized; in place of relay INWP, the operation of the system is similar to that already described with the exception that lamp Y of signal 2B will be lighted in place of lamp G of that signal, to designate that the diverging route is established anda. detailed description of the operation of the system under this condition is deemed unnecessary.

coming energized to light lamp G of signal 2A in 1 place of lamp Y to change the indication displayed by signal 2 from caution to proceed.

If now a train in section 2T enters section IT,

relays ITR, 2HY, 2H and 2D release, restoring signal 2 to stop, but mechanism 2V will. beheld energized by a retaining, circuit including front contact b .of relay WP, and back contacts 12 of relays ITR. and" Z'I-R, until. the: entire train has passed the trip arm 2a,;whereuponmechanism 2V and relay ZVP- will berel'eased by the opening of back contact b-of: relay 2m to restore arm 2a to its operative position.

To clear signal 2- for a following train, after sections IT and. 41" are vacated, lever 2SG must first be restored to normal to. pick up'rela'y 2HY over thelever contact .a-,and mechanism 2V must be released to close its contact b in the pick-up circuit for relay 2H.

Assuming next that it-is-desired to pass a following train from section. 2T to section IT at slow speed, before section vI'I' or 4T is'vacated'. Since relay ZH Y is held released,

relays

2H and 2D do not pick up when lever ZSG is reversed. The operator pressesthe ca-ll-on push button 200, and since relay 2TB has been. released by the approaching train, this completes a circuit from terminal B at back contact b of relay 2D over back contact-e of relay 2H, contact a of button 2G0- and contactcof lever ZSG through relay 2008 to; terminal C at back contact a of relay 2TB, sotha-t'relay 2COS picks up completing a stick circuit at its own. front contact (1 extending to terminal B at contact I) of lever ZSG.

Relay 2D 'thenbecomes energized; over the circuit fromterminal B atcontactd of relay INWP, contact 22. of. relay ZCOS, back contacted of relay 2H through relay 2D to terminal C, and relayZD completes-a circuitover its contact 0 and contact c of relay 2.603 to lightlamp-Y of the call-on signal 20, lamps R of signals 2A and 2B also being lighted.

The trip' arm 2a remains inits-operative position, since relay 2H has not beenenergized, but may be retracted by the operation of akey or push button PB- by thetrain crew, thereby completing a circuit over. contact 12 of: relay 2D to energize mechanism 2V.. Relay ZV-P' then picks up and its contact b completesastick circuit for mechanism 2V extending to terminal Bat contact e of relay 2D sothat mechanism. 2V remains energized after button PB isreleased. The lamps R are now lighted over front contact aof relay ZVP and back contact 0. ofrela-y 2-H.

It will be seen that as the train passes the call-on signaland vacates section 2T, theopening of back contact aof relay 2TB .releasesrelays 20.05 and 2D; and since *back. contactb: of. relay is also open, relay .211 releases mechanism It will: be seen that lamp Y of signal 20 is not l'ightedwhen relay 2D is picked up by the operation.of. relay 2H because relay 2H can pick up only when relay 2008 is released to open the lamp circuit. Lamp Y of signal 2A does not flash when the signal aspect changes from proceed to stop; because the release of relay 2D follows that of relay 2H. Temporarily, that is, for the release period of relay 2D,. relay- 2D is picked up with relay 2H released as required for the display of the call-on signal: 26;. but lamp Y of signal 20 does not flash because relay 200s cannot be picked up to complete the-lamp-circuit until back contact b of relay 2D closes.

Although I have hereinshown and described only one form of apparatus. embodying my invention, it is understood that. various changes and modifications may be made therein within the scope of. the appended'claimswithout departing from the spirit. andrscopeof my invention.

Having thus described. my invention; what I claim is:

1-. Railway tra-fiiccontrolling apparatus comprising a railway signal adapted to display stop, caution and proceed-indications and to also display a call-on indication, a home relay con trolled by trailic conditions and a distant relay controlled overaf-ront contact of said home relay by other traflict conditions for controlling said signal, circuits'controlledby the home relay for changing the: indication of said signal from stop to cautionwhen. the homerelay is en ergized and to proceed when: the distant relay is also energized, a manually controllable stick relay having a pick-up circuit. arranged to be closed. only when. the home and distant relays are released and a stickcircuit independent thereof, circuits controlled. by said stick relay when picked up for energizin said distant relay while maintaining said-home relay released, and means for causing the display of said call.- on indication. whensaid distant relay is energized by theoperationof said. stick relay.

2. Railway trainee-controlling apparatus comprising a railway signal adapted to display any one of four distinctive indications, a home relay controlled by trafiic conditionsanda distant relay controllable by other traific conditions for controlling said signal, circuits controlled by the home relay for changing the aspect of said-signal from one indication to another when the home relay is energiZedz-and to a third indication when thehome and. distant relays are both energized, a stick relayhaving a pick-upcircuit arranged. to be closed: only when. the home and distant-relays are. both released and a" stick circuit independent thereof, circuits controlled by said stick relay when picked upforenergiz- .ing: said distant relay while maintaining said .home relay released, and circuit means: effective when said-distant relay. andisaid stick relay are relay is energized singly and to display a third indication when both relays are energized, manually controllable means for energizing said one relay in accordance with traflic conditions in a first portion of the route established by the switch which is directly in advance of the signal and for energizin the other relay when said one relay is energized in accordance with traific conditions in a second portion of the route established by the switch which is in advance of said first portion, a stick relay manually operable when said one signal relay is released, means controlled by said stick relay for energizing said other signal relay irrespective of traffic conditions in advance of a signal provided the one signal relay is released and a route over the switch is available, and means for causin said signal to display a fourth indication when said other signal relay is energized by said stick relay.

4. In combination with a railway signal, two signal relays for controlling the indications displayed by said signal, circuits controlled by said relays for causing the signal to indicate stop when both relays are released, to indicate caution when one relay is energized and to indicate proceed when both relays are energized, manually controllable means for energizing said one relay effective only when a first section of track directly in advance of the signal is unoccupied, means controlled by said one relay when energized for energizin the other signal relay in accordance with traffic conditions in a second section of track in advance of said first section, manually operable means for energizing said other signal relay when said one relay is released due to the occupancy of said first section, and a circuit controlled jointly by said manually operable means and said other signal relay for causing said signal to display a distinctive call-on indication when said one signal relay is released and said other signal relay is energized.

5. In combination with a railway signal, an automatic train stop having a trackway tripping member adjacent said signal and an operating mechanism which when energized retracts said tripping member to a non-operative position, two signal relays for controlling the indications displayed by said signal and for also controlling said mechanism, circuits controlled by said relays for causing the signal to indicate stop when both relays are released or when said mechanism is energized, and to indicate caution or proceed according as one or both of said signal relays are energized provided said mechanism is also energized, manually controllable means for energizing said one signal relay effective only when a first section of track directly in advance of said signal is unoccupied, means rendered effective when said one signal relay is energized for controlling the other signal relay in accordance with the condition of occupancy of a second section of track in advance of said first section, manually controllable means for energizing said other signal relay when said one signal relay is held deenergized due to the occupancy of said first track section, a circuit for energizing said mechanism closed when said one signal relay is energized, and a second circuit for energizing said mechanism including a normally open manually operable contact adjacent said signal and a front contact of said other signal relay.

JOHN R. MYERS.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,792,364 Penrod et a1 Feb. 17, 1931 2,168,816 Young Aug. 8, 1939 2,337,204 Mills Dec. 21, 1943 2,355,499 Allen Aug. 3, 1944