US2100432A - Railway signaling system - Google Patents

Description

Nov. 30, 1937. PH. CRAGO 2,100,432.

RA ILWAY SIGNALING SYSTEM Original Filed June lO, 1956 g 5 ,3 10 $15? I A INVENTOR Paul H. 90

HIS ATTORNEY Patented Nov. 30, 1937 UNITED STATES PATENT OFFICE RAILWAY SEGNALING SYSTEM Paul H. Crago, Wilkinsburg, Pa, assignor to The Union Switch & Signal Company, Swissvale, pa a corporation of Pennsylvania A we,

Original application June 10, 19.3.6, Serial: No. 84,498. Divided and this application April 10, 1937, Serial- No. 136,118

6 Claims. (01. 246-46) means for causing, an approach lighted signal to shown disposed-above the associated roundels, but 5 display a restrictive indication when a train apit will; be readily understood that in actual pracproaches the signal if the filament of the lamp tice each. lamp will be located directly back of the for the signal next in advance becomes burned out associated roundel, and will have associated or broken. therewith a suitable optical system, not shown,

10 Other objects of my invention will appear as for projecting a beamof light from the lamp. 1 the description proceeds. The signals Seach indicate proceed, stop, or,

The present application is a division of my cocaution according as the .roundel G, R, .or Y pending application, Serial No. 84,498, filed on is in front of the associated lamp L when this; June 10, 1936, for Railway signaling systems. lamp is lighted. Operatively'connected with each I will describe one form of railway signaling armature 5 is a circuit controller comprising two 1 system embodying my invention, and will then movable contact fingers land 8. The movable point out the novel features thereof in claims. contact finger? cooperates with a fixedcontact 1e The accompanying drawing is a diagrammatic toolose a contact '!''l when: the armature 5pc:- view showing one form of signaling system emcupies its right-hand extreme position, and with bodying my invention. a fixed: contact lto close a contact l-l when Referring to the drawing, the reference characthe armature occupies its interm d a e po ters I and l designate the track rails of a stretch or its left-hand extreme position; While themovof railway track along which traflic normally able contact finger 8 cooperates with a fixed conmoves in the direction indicated by the arrow. tact 8 to close a contact 8-8 when the arma- These track rails are divided, bymeans. of insuture occupies its left-hand extreme position, and 25,

lated joints 2, to form blocks, only one of which, with a fixed contact 6- to close a contact 8 -8 AB, is shown complete in the drawing; Each when the armature occupies its intermediate or'." block. is provided with a track circuit comprising its right-hand extreme position. A signal ofthe atrack relay, designated by the reference charactype described is disclosed and. claimed in Letters ter TR with a suitable distinguishing exponent, Patent of the United States No. 1,864,224, granted and connected across. the rails adjacent one end to Wesley B. Wells, on June 21, 1932, for Light of the section, and a suitable source of track cir- S nals. cuit current, hereshown as atrack battery 3, con- Associated with each signal is a slow-releasing nected across the rails adjacent the other end of Signal repeater el y designated y reference 35. the section. character SR. witha suitable distinguishing ex Located adjacent the entrance end of each ponent, an approach lighting relay designated by block is a signaldesignated by the reference charthe reference character ALR with a suitable disactor s with an exponent corresponding to the tinguishing exponent, andasl w-releasing li htlocation. Each signal, as here shown, is of the out relay designated by the reference character 4 type commonly known as: a searchlight signal, and 'LOR with a suitable distinguishing exponent. 40 comprises an armature 5 mounted to rotate be- Each lightout relay LOR is provided with two tween an intermediate position to which it is windings, one of which, 9, has a sufiiciently high biased, and two extreme positions. Each armaresistance so that when this winding is connected ture 5. is controlled by an armature winding 6, in series with the filament of the lamp L ofthe.

and is polarized by the field from a permanent associated signal in. a checking circuit for the 45 magnet or an electromagnet (not shown) in such lamp presently to be described, the lamp will, not manner that when the winding 6' is energized, the become lighted, and the other of which, It, has a armature will rotate to its right-hand or leftsnfficlently low resistance so that when this wind: hand extreme position according as winding 6 is ing is connected. in series with the filament of the then supplied with current of normal or reverse lamp L of the associated signal in an energizing polarity, respectively. Attached to each armjacircuit for the lamp presently to be described, ture 5 to rotate therewith are three colored the lamp will become lighted. roundels G, R, and Y, which are arranged to be Each signal repeater relay is provided with disposed in the path of abeam of light projected two energizing circuits which are controlled by r from an associated lamp L according as the the circuit controller of the associated signal.

My invention relates to railway signaling systems of the type involving light signals which are approach lighted.

One object of my invention is to provide novel extreme position, respectively. For convenience in illustration, each lamp L in, the drawing is advance.

when track relay TR and lightout relay LOR Referring to relay SR for example, the one energizing circuit for this relay is closed when and only when signal S indicates proceed, and passes from terminal X of a suitable source of current not shown in the drawing through contact of signal S wires 24 and 25, and the winding of relay SR to terminal The other energizing circuit for relay SR is closed when and only when signal S indicates caution, and passes from terminal K through contact '!l of signal S wire 32, contact 8-8? of signal S wire 25, and the winding of relay SR to terminal 0. It will be apparent, therefore, that relay SR will be energized when signal S occupies either'its proceed or its caution position, but will be deenergized when signal S occupies its stop position. Relay SR is made sufficiently slow releasing so that it will not open its front contacts while signal S is moving from its proceed to its caution position, or vice-versa.

' The winding 6 of each signal is controlled by the associated track and lightout relays and by the signal repeater relay for the signal next in advance, through the medium of a polarized line circuit which includes the winding of the approach lighting'relay for the signal next in 7 Referring to signal S for example,

are both energized, and signal repeater relay SR is also energized, the polarized line circuit for winding 6 of signal S is closed,and under these conditions, winding 6 is supplied with cur rent of normal polarity, the path of the current being from terminal X through the winding of relay ALR wire I2, front contact !-l3 of relay SR line wire l4, front contact 15 of track relay TR wire 56, front contact ll of lightout relay LOR wire 18, winding 5 of signal S wire l9, front contact 2i! of track relay TR line wire 2|, front contact 22--22 of signal repeater relay SRB, and wire 23 to terminal 0. When track relay TR and lightout relay LOR are both energized and signal repeater relay SR is deenergized, the polarized line circuit for winding 6 of signal S is again closed, but under these conditions, dueto the fact that the back contacts l3' l3 and 22-42 of relay SR) are then.

closed instead of the front contacts |3--l3 and 22-42 winding 6 of signal S is supplied with current of reverse polarity over this line circuit. When either track relayTR or lightout relay LOR is deenergized, the polarized'line circuit for winding 5 of signal S will, of course, be open.

It will be apparent, therefore, that when track relay TR and lightout relay LOR are both energized," the mechanism of signal S will occupy its proceed orits caution positionaccording as signal repeater relay SR is then energized or deenergized, but that, when either track relay TR. or lightout relay LOR is deenergized, the mechanism of signal S will occupy its stop po-' sition. It will also be apparent that approach lighting relay ALP?) will be energized whenever winding 6 of signal S is energized by current of either normal or reversepolarity, but that, when winding 5 of signal S is deenergized, ap-

proach lighting relay ALR 'will also be deener- 'gized.

Each signal lamp L is provided with an energizingi circuit which is controlled'by the associated' signal repeater and. approach lighting relays in such manner that this circuit will become closed when either of these relays becomes deenergized, and which includes the low resistance winding of the associated lightout relay. Each and 21, back contact 28 of relay SB connected in multiple with back contact 29 of relay ALR wire 3!], winding it of relay LO-R and wire 3| to terminal 0. The checking circuit for lamp L passes from'terminal X through the filament of lamp L wire 26, resistor R and the winding 9 of lightout relay LOR to terminal 0. The parts are so proportioned that lamp L will become lighted when and only when the energizing circuit for the lamp is closed, but that, relay LOR will hold its front contacts closed when either the energizing or the checking circuit for lamp L is closed.

It should be pointed out that while, as shown I in the drawing, each checking circuit includes a associated lamp from becoming incandescent while the checking circuit in which the resistance is included is closed and the associated energizing circuit is open; It should also be'pointed outthat when the energizing circuit for a lamp is closed, the checking circuit is also closed, so that the current which is supplied to the lamp flows through the windings 9 and ill of the associated lightout relay in parallel. The windings 9 and II] are so arranged that the fluxes set up in the relay when both of these windings are energized are cumulative.

As shown in the drawing, all parts are in their normal positions, that is to say, all relays are picked up, the winding 6 of each signal is supplied with current of normalv polarity, so that the armatures 5 or. signals S and S both occupy their right-hand or proceed positions, and the lamps L and L are both extinguished.

Inexplaining the operation of the apparatus as a whole, I will first assume that a train moving in the direction of the arrow traverses the stretch oftrack shown in the drawing. When the train enters the block in rear of block A-B, theshunting of the track relay associated with this block' will cause approach lighting relay ALR to become deenergized and close its back contact 29. The closing of this contact will complete the energizing circuit for lamp L and this lamp will therefore become lighted and will cause signal S to display a proceed indication.

When the train enters block A-B, track relay TR will become deenergized, and will interrupt the circuit for'winding 6 of signal S, thuscausing the mechanism of this signal to move to its which was previously closed for signal repeater relay SB and since both circuits for this relay will then be open, this relay will become deener gized. The deenergization of relay SR will cause.

the polarity of the current supplied to the circuit for the winding 6 of the signal for the block to the rightfof block AB'to become closed, and as a result, as soon as the train moves out of this block, this signalwill move to its caution position. The deenergization of relay SR will also cause this relay to complete, at its back proach lighting relay ALR picks up'due to the train having passed out of the block to the right of block AB, signal S will continue to display The deenergization of apa stop indication. proach lighting relay ALlR. will cause the energizing circuit for lamp L of signal S to become closed, and this lamp will therefore become lighted, thus causing signal S to display a proceed. indication. K

When the train enters the block to the left of block AB, track relay TR will become deenergized and will cause winding 5 of signal S to become deenergized. The deenergization of winding 6 of signal S will cause the mechanism of this signal to move to its stop position, which movement, in turn, due to the resultant operation of the associated circuit controller, will deenergize signal repeater relay SR When relay SR becomes deenergized, it will reverse the polarity of the current supplied to the circuit for winding 5 of signal S but as long as any part of the train remains in block A-B, the circuit for winding 6 will remain open at the front contacts of track relay'TR and signal S will continue to display a stop indication. As soon, however, as the train passes completely out of block AB,

' the resultant energization of track relay TR will complete the circuit for winding 6 of signal S and this signal will then move to its caution position. The movement of signal S to its caution position will complete the previously traced circuit for signal repeater relay SB including contacts and 83 of the circuit controller of signal S and relay SR will then pick up.

When this relay picks up, it will interrupt the energizing circuit for lamp L and will cause the winding 6 of the signal for the block tothe left of block AB to be supplied with current of normal polarity, whereupon the mechanism of this signal will move to its proceed position.

When the train leaves the block to the left of block A-B, track relay TR will pick up and will cause signal S to move to its caution position in the same manner that the picking up of track relay TR caused signal S to move to its caution position. As soon as signal S reaches its caution position, signal repeater relay SR will pick up, whereupon signal lamp L will become extinguished, and the mechanism for signal S will move to its proceed position. When the train passes out of the second block in advance of block AB, signal S will move to its proceed position, and all partswill then be restored to the positions in which they are shown in the drawing.

I will now assume that with the parts in the positions in which they are shown in the drawing, the filament of lamp L becomes brokernand that a train subsequently'enters the block to the right of point A. When the filament of lamp L becomes broken, the checking circuit for this lamp becomes interrupted at the lamp filament, and lightout relay LOB. therefore becomes deenergized, and opens its front contact H. The opening of this front contact will deenergize the winding 6 of signal S whereupon the signal mechanismof this signal will move to its stop position. When the mechanism of signal S moves to its stop position, signal repeater relay SR will become deenergized, and will reverse the polarity of the current supplied to winding 6 of signal S thus causing the mechanism of signal S to move to its caution position. As a result, when the train enters the, block to the right of point A and causes approach lighting relay.

ALR to-become deenergized and complete "the circuit for lamp L signal S will indicate caution even though neither of the two blocks in advance of point A is occupied.

Ii' signal S occupies its caution position instead of its proceed position when the filament of lamp L becomes broken, and a train subsequently enters the block to the right of point A, the operation of the apparatus will be similar in all respects to that just described. It will be seen, therefore, that with a signal system constructed in the manner described, if the filament of a signalslampbecomes broken when the mechanism of the si nal in the rear occupies its proceed position, the mechanism of thesignal in the rear:

become lighted due to the presence of a train in the block immediatelyin rear of thesignahboth the checking andenergizing circuits for the lamp will become open, .andthe associated 'lightout:

relay will become deenergized, and will thuscause i the signal mechanism to move to itsxstop position;

This is desirable because since the operating rules of railroads usually require that a dark signal be obeyed as a stop signal, and since the signal mechanism occupies its stop position, if any light from an extraneous source such, for example, as a locomotive headlight orth-e suns rays when the sun is close to thehorizon, should enter the signal and be reflected back by the optical assembly or" the signal, the resulting phantom indication would be a stop indication. The signal mechanism, after being moved to its stop position in the manner just described, will subsequently remain in its stop position until the burned out lamp is replaced, and the-signal next in rear will be prevented from moving to it's proceed position,

even though trafiic conditions in advance are such that the mechanism of this signal would normally assume its proceed position.

Although I have herein shown and described only one form of railway signaling system embodying my invention, it is, understood that vari- 2 one changes and modifications may be made therein within the scope of the appended claims without departing from the spirit and scope of my invention, a

Having. thus described my invention, what I claim is: i

1. In combination, a stretch of railway track 7 divided into blocks, a relay associated with each block, each said relay having two windings, a signal for each block controlled by traffic conditions in advance and by the associated relay and includinga lamp which at times becomes lighted to cause the signal to display an indication, a constantly closedcheckingcircuit for each lamp including the one winding of the associated relay and effective for energizing the associated relay but not for energizing the associated lamp, and means effective when a train approaches a signal for connecting the other winding of the associated relay in parallel with the one Winding 2.'In combination, a stretch of railwaytrack divided into blocks, a relay associated with each block, each said relay having a high resistance and a low resistance winding, a signal for each block controlled by traffic conditions in advance and by the associated relay and including a lamp which at times becomes lighted to cause the signal to display an indication, a constantly closed checking circuit for each lamp including the high resistance winding of the associated relay and effective for energizing the associated relay but not for energizing the associated lamp, and means effective when a train approaches, a signal for connecting the low resistance winding'of the associated relay in parallel with the high resistance winding to thereby cause the signal lamp to become lighted.

3. In combination, a stretch of railway track divided into blocks, a track circuit for each block including a track relay; a signal for each block capable of assuming a proceed, caution, or stop position according as the signal mechanism is supplied with current of normalpolarity, reverse polarity or is deenergized, each said signal including a lamp which at times becomes lighted to cause the signal to display an indication; a'signal repeater relay controlled by each signal and arranged to be energized at all times except when the signal occupies its stop position, a lightout relay for each signal having two windings, an approach lightingrelay for each signal; an energizing circuit for each signal mechanism including a front contact of the associatedlightout relay, a front contact of the track relay for the associated block, pole changing contacts of the signal repeater relay for the signal next in advance and the winding of the approach lighting relay for the signal next in advance, the parts being so proportioned that each signal energizing circuit will contact of the associated approach lighting relay and a back contact of the associated signal repeater relay in multiple. l

4. In combination, a stretch of-railway track divided into blocks, a track circuit for each block 7 including a track-relay; a signal for each block capable of assuming a proceed, caution, or stop position according as the signal mechanism is supplied with current of normal polarity, reverse polarity or is deenergized, each said signal including a lamp which at times becomes lighted to cause the signal to display an indication; a signal repeater relay controlled by each signal and arranged to be energized at all times except be supplied with current of normal or reverse with the one winding of such relay over a back when the 'sig'naloccupies its stop position, a lightout-relay forleachsig nal having a high resistance and a lowresistance winding, an approach lighting relay for each signal; an energizing circuit for each signal mechanism including a front contact of the associated lightout relay, a frontcontact of the track relay for the associated block, pole changing contacts of the signal repeater relay for the signal next in advance and the winding of the approach lighting relay for the signal next in advance, the parts being so proportioned that each signal energizing circuit will be supplied with current of normal or reverse polarity according as the signal repeater relay which controls it is picked up or released, and that each approach lighting relay will be picked up whenever the signal energizing circuit in which it is included is closed; a constantly closed checking circuit for each lamp including the high resistance winding of the associated lightout relay and effective for energizing the associated lightout relay but not for energizing the associated lamp, and another circuit for each lamp including the low resistance windings of the associated relay connected in parallel with the high resistance winding of such relay over a back contact of the associated approach lighting relay and a back contact of the associated signal repeater relay in multiple. 7

5. In combination, a stretch of railway track divided into blocks, a two winding relay associated With each block, a signal for each block con-. trolled by the associated relay and by traffic con-. ditions'in advance and including a lamp which at times becomes lighted to cause the signal to display an indicatioman energizing circuit for each lamp controlled by traflic conditions in rear of the associated signal and including one winding of the associated relay, and a constantly closed checking .circuit for the lamp including the other winding of the associated relay.

6. In combination, a stretch of railway track divided into blocks, a signal for governing the entrance of traific into each block including a winding and a lamp and responsive to reversals in the polarity ofthe current supplied to the winding, a track circuit for each block including a track relay, a slow-releasing signal'repeater relay for eachsignal energized whenever the winding of theassociated signal is energized, a lightout relay for each signal having a low resistance wind ing and a high resistance winding; a polarized line circuit for each signal including the winding of the signal, a front contact of the associated lightout relay, airontco'ntact of the associated associated approach lighting-relay, anda constantly closed checking circuit for each lamp including the high resistance winding of the associated lightout relay.

7 PAUL H. CRAGO.

track relay, pole-changing contacts of the signal repeater relay for the signal next in advance and

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