US2300757A - Railway signal control and indication apparatus - Google Patents

Description

Nov. 3, 1942. Hi 5, YOUNG 2,300,757

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. 7 BY Q [2 2, i flab BIS ATTORNEY H. s. YOUNG Nov. 3, 1942.

' RAILWAY s'IemL couTRoL AND INDICATION APPARATUS Filed Nov. 28, 1940 2 Sheets-Shet 2 i M Wm Patented Nov. 3, 1942 UNlTED STATES PATENT orrlcr;

RAILWAY SIGNAL CONTROL AND INDICATION APPARATUS Henry S. Young, Wilkinsburg, Pa., assignor to The Union Switch & Signal Company, Swissvale, Pin, a corporation of Pennsylvania Application November 28, 1940, Serial No. 367,490

11 Claims.

My invention relates to railway signal control and indication apparatus, and more particularly to such apparatus in which a signal is manually controlled by a circuit including a pair of con- .ductors extending from a control point to a signal location, andin which an indication device at the control point is controlled from thesignal location by a circuit including thesame pair of conductors.

A feature of my invention, in order to use the same pair of line conductors for the control and indication circuits, is the provision, at the signal location, of an indication relay which becomes energized in response to-energization of a signal control relay, and which controls and is retained in an energized condition by the indication circuit for energizing the indication device.

I shall describe a few forms of apparatusembodying my invention, and shall thenpoint out the novel features thereof inclaims;

In the accompanying drawings, Fig. 1' is a diagrammatic view showing one form of apparatus embodying my invention, in which control and indication circuits are provided for a single signal which governs trafiic movements over a track switch in both its normal and its reverse position; Fig. 2 shows a modified form of the apparatus of Fig. l, in which control circuits are provided for a control and an indication relay for each of two signals one of which directs traflic movements over the switch in its normal position and the other of which directs movements over the switch in its reverse position; Fig. 3 shows a modified form of the apparatus of Fig. 2 in which only one indication relay is used for the two signals; Fig 4 is a modification of a portion of Fig. 1, showing contacts of a train responsive relay in only the signal control circuits; and Fig. 5 is a modification of a portion of Fig. 1-, showing a contact of the train responsive relay in only the indication circuit.

Similar reference characters refer to similar parts in each of the views.

Referring first to Fig. l, a signal 2 is shown for governing traffic movements over a track switch I in both the normal and the reverse position. Signal 2, as here shown, is of the color light type having a caution lamp Y and a stop lamp R, but may be of any other suitable design.

A portion of the stretch of railway trackin which switch I is located is divided from adjoining portions by means of insulated joints 3 to form a section designated IT. This section is provided with a usual track circuitincluding a battery 5 connectedacrossthe rails adjacentone end of section IT, and a track relay designated by the reference character ITR connected across the rails adjacent the opposite end of the section.

Switch I is operated between its normal and reverse positions by a mechanism W which is controlled by a manually operable lever IV- in its normal andreverse positions n and r, respectively.

A signal control lever 2V of a usual type is shown having a'norm'al position 11., a-reverseposition I to the left, and a reverse position 1' to the right, and also having" an indication position b to the left and an indication position cite the right. LeVer'ZV can be moved-to-its 1 position to control apparatus shown in the drawings which effects the clearing of signal- 2. Similar apparatus could also be controlled by moving le'ver 2V to its j position to effect-clearing of a similar signal for governing trafl'lc movements in the opposite direction. A contact 11- operated by lever 2V is closed while lever 2-V-'is in its Upositionor its (1 position or at any point between these two positions. Contacts l3 and 22, also operatedby lever 2V, are closed when lever 2V is in only its 7" position, and contacts 25 and 26,

operated by'lever 2V, are closed'when lever 2V is in only its d position.

Levers IV and 2V aremechanically interlocked, as indicated by the da'shline 6, so that lever LV can bemoved between its 11. and r positions only when lever 2V is in the 11. position.

A track relayrepeater stick relay lTPS-is' provided.- witha pick-up circuit which is controlled by relay [TR and by contact H of lever'2V, and is provided with a stick circuit which is controlled by relay ITR. Relay ITPS, after becoming deenergized while lever 2V is in one of its. reverse positions, can therefore again become energized only when lever 2V is. returned to one of its indication positions.

A signal control reIayZ-HRisprOVided with a pick-up and astick circuit, both of Whichinclude line conductors l5 'and 20 and are con.- trolled by lever 2V in its 1 position and by front contacts of relay' ITPS. The pick-up circuit for relay ZHR is also controlled by backcontacts of a signal indication relay 2MB. Relay 2I-IR controls the lighting-of lamps Y and R of signal 2:

Signal indication relay 2MB, which is here shown as of the slowrelease type, has a pick-up circuit controlled by a front contact of relay ZHR.

An indication circuit is controlled: by back contacts of relay ZHR, by front contacts of relays 2MB. and ITPS, and by contacts 25 and 26 of lever 2V for energizing an indication magnet M and for retaining relay 2MR in an energized condition. The indication circuit includes the same pair of line conductors I5 and 29 as the control circuits for relay 2BR.

Indication magnet M controls a latch I which, when magnet M is deenergized, drops down onto a locking segment K. Segment K is rigidly connected with lever 2V, and hence lever 2V can be moved only if segment K is free to move. When lever 2V is being returned from a reverse position to its 11. position, latch 'I engages a projection 8 and so locks segment K, thus preventing further movement of lever 2V toward its n position until magnet M becomes energized.

As shown in the drawings, all parts of the apparatus shown in Fig. l are in the normal condition, that is, switch I is in its normal position; lam'p R of signal 2 is lighted; relay ITPS is energized; levers IV and 2V are in the normal or n position; and relays 2I-IR and ZMR and indication magnet M are deenergized.

Switch W has been moved to its normal position because of a circuit passing from terminal B of a suitable source of current, not shown in the drawings, through contact 9 of lever IV in the at position, and mechanism W of switch I to terminal of the same source of current.

Both the pick-up and the stick circuit for relay ITPS are closed, the pick-up circuit passing from terminal B, through contact IU of relay I TR, winding of relay I'I'PS, and contact I I of lever 2V to terminal C. The stick circuit passes from terminal B, through contact II] of relay ITR, winding of relay ITPS, and contact I2 of relay ITPS to terminal C.

In order to clear signal 2, a leverman will move lever 2V to its 1 position, thereby completing a pick-up circuit for relay ZHR, this circuit passing from terminal B, through contact I3 of lever 2V, front point of contact I4 of relay I TPS, line conductor I5, back point of contact I6 of relay ZMR, winding of relay 2HR, contact I I of relay 2MR, line conductor 20, contact 2| of relay ITPS, and contact 22 of lever 2V to terminal 0. Relay 2HR, upon becoming energized, completes its own stick circuit passing from terminal B, through contact I3 of lever 2V, front point of contact I4 of relay ITPS, line conductor I 5, contact I8 of relay 2BR, winding of relay ZHR, front point of contact I9 of relay ZI-IR, line conductor 29,

contact 2I of relay ITPS, and contact 22 of lever 2V to terminal 0.

Relay ZHR, upon becoming energized, opens a circuit including a back point of contact 23 of relay ZHR, by which lamp R of signal 2 is normally lighted, and then completes a circuit for energizing lamp Y of signal 2 through the front point of contact 23.

Relay ZHR, upon becoming energized, also completes a circuit for energizing relay 2MB, this circuit passing from terminal B, through the front point of contact 24 of relay ZHR, and the winding of relay ZMR to terminal C.

When a train enters section IT upon passing signal 2, relay ITPS will become deenergized at contact .III of relay ITR, and will then open its contacts I4 and 2|, thereby causing relay 21-13. to also become deenergized and cause signal 2 to again display the red or stop indication. Relay ZHR, upon becoming deenergized, completes a stick circuit for relay 2MB. passing from terminal B, through the back point of contact 24 of relay ZI-IR, front point of contact I6 of relay 2MB, line conductor I'5, back point of contact I4 of relay ITPS, line conductor 20, back point of contact I9 of relay ZHR, and the winding of relay 2MB to terminal C.

When the train leaves section IT, relay ITPS will not :become energized until lever 2V has been returned to its (1 position. Signal 2 can therefore not again clear until lever 2V has been returned to its (1 position and again operated to the r position.

.When lever 2V is returned to the 11 position and relay ITPS has again become energized, an indication circuit will be completed, passing from terminal B, through the back point of contact 24 of relay ZI-IR, front point of contact N5 of relay 2MR, line conductor .I=5, front point of contact I4 of relay I'IPS, contact 25 of lever 2V, winding of indication magnet M, contact 26 of lever 2V, contact 2-I of relay I'TPS, line conductor 20, back point of contact I9 of relay ZHR, and the winding of relay ZMR to terminal C. The resistances of relay ZMR and indication magnet M are so proportioned that relay ZMR will retain its front contacts closed and indication magnet M will lift latch I out of engagement with projection 8 of locking segment K. The movement of lever 2V can now be completed to its n position. Relay 2MR and magnet M will then become deenergized on account of the indication circuit being opened at contacts 25 and 26 of lever 2V.

From the foregoing description of the control of signal 2, it follows that semi-automatic stick control is provided for this signal on account of contacts I4 and H of relay ITPS being included in the control circuits for relay ZHR.

Route locking is also provided on account of contacts -14 and 21 of relay ITPS being included in the indication circuit. The route locking is effective while a train occupies section IT, because of magnet M remaining deenergized as long as the train in section IT prevents relay ITPS from becoming energized and completing the indication circuit. With magnet M deenergized, lever 2V cannot be returned beyond the d position, and hence lever IV is mechanically locked in its normal or its reverse position.

Cross protection is provided by the arrangement shown in Fig. 1 as described in the following examples:

1. In the event of a positive cross on conductor I5 while lever 2V is in the n position, current would flow through the back point of contact It of relay ZMR, winding of relay ZHR, contact II of relay 2MB, back point of contact I9 of relay ZHR, and the winding of relay ZIVDR to terminal C. Relay 2HR would then start to pick up, but would open the circuit at the back point of its contact I9. This would result in flashing of the light Of signal 2, but would not produce a proceed signal indication.

2. A negative cross on line conductor I5 would shunt the circuit for picking up relay 2I-IR because both sides of the circuit would then have negative polarity, and hence relay ZI-IR would not be falsely picked up. The circuit for magnet M would be similarly shunted by a negative cross on conductor I5.

3. A positive cross on conductor 20 would shunt the circuits previously traced for relay 2HR and magnet M.

4. A negative cross on conductor 28 would not affect the normal operation of relay .2HR, but would shunt the holding circuit for relay ZMR.

Referring now to Fig. 2, a high speed signal 4, represented as of the semaphore type, is here shown' for governing traffic movements over switch I in its normal position, and a low speed signal 2 is shown for governing trafilc movements over switch I in only its reverse position instead of over switch I in both the normal and the reverse position as in Fig. 1.

Contacts l3 and 22 of lever 2V, upon becoming closed, here effect energization of a slow release signal control relay 4HR or ZHR according as contact 21 operated in conjunction with switch I is closed in the normal or the reverse position corresponding to the position of switch 1. Pick-up circuits for slow release signal indication relays 2MB and 4MR ar controlled by front contacts of relays ZH-R and 4HR, respectively, and corresponding indication circuits energize indication magnet M and retain one or the other of the relays ZMR and 4MR in an energized condition Th pick-up circuit for relay 2HR in Fig. 2 differs from the pick-up circuit shown for this relay in Fig. l by including contact 27 of switch l in the reverse position. The stick circuit for relay 2HR. in Fig. 2 differs further from its stick circuit shown in Fig. 1 by includin front contacts of relay 2MB.

If a leverman desires to clear signal 4 while switch i is in the normal position, he will move lever 2V to the 1' position, thereby completing a pick-up circuit for relay ll-IR passing from terminal B, through contact 53 of lever 2V, line conductor I5, contact 21 of switch I in the normal position, back point of contact 28 of relay 4MB, winding of relay 4BR, back point of contact 3! of relay 4MB, back point of contact 32 of relay 2BR, back point of contact 33 of relay ZMR, line conductor 20, and contact 22 of lever 2V to terminal C. Relay 4HR, upon becoming energized, will complete a circuit for energizing relay 4MR passing from terminal B, through front point of contact 34 of relay ll-IR, and the winding of relay 4MB to terminal C. Relay 4MB, upon becoming energized, completes a stick circuit for relay 4BR which is the same as the pick-up circuit previously traced as far as contact 21 of switch i, then passing through the front point of contact 28 of relay 4MR, front point of contact 29 of relay 4HR, winding of relay 4BR, contact 38 of relay ll-IR, front point of contact 3! of relay 4MB, back point of contact 32 of relay ZHR, back point of contact 33 of relay 2MB, line conductor 20, and contact 22 of lever 2V to terminal C.

With relay 4HR energized, a circuit is completed for operating signal 4 to the proceed position, passing from terminal B, through contact 35 of relay 4HR, and th mechanism of signal 4 to terminal 0.

When the leverman later desires to return signal 4 to the stop' position, he will return lever 2V to the 11 position, thereby opening the stick circuit for relay 4H3 which then becomes deenergized and opens its contact 35, causing the arm of signal 4 to return to the stop position. Relay 4HR, upon becoming deenergized, completes a second pick-up circuit for relay 4MB, passing from terminal B, through contact 3631 of signal 4, which is closed from th time signal 4 is clear until just before the arm of signal 4 reaches the stop position. The second pick-up circuit for relay 4MB, then passes through the back point of contact 34 of relay ll-IR. and the winding of relay 4MB to terminal C.

When the arm of signal 4 reaches the stop position, an indication circuit will be completed, passing from terminal B, through the back point tact 28 of relay 4MB, contact 21 of switch W, line conductor I5, contact 25 of lever 2V, winding of magnet M, contact 26 of lever 2V, line conductor 26, back point of contact 33 of relay 2MB, back point of contact 32 of relay ZHR, front point of contact 3'! of relay 4MB, contact 3? of signal 4, back point ofcontact 34 of relay ll-IR, and the winding of relay 4MB to terminal C. The movement of lever 2V can now be completed to the n position.

In order to clearsignal 2 while switch I is in its reverse position, the leverman will move lever 2V to the 1" position, completing a pick-up circuit forrelay'ZHR, passing from terminal B,

through contact I3 of lever 2V, line conductor [5, contact 27 of switch W closed in the reverse position, back point of contact 38 of relay 2MB, winding of relay 2-I-IR, back point of contact 33 of relay 2MR', line conductor 20, and contact 22 of lever'2V to terminal C. Relay ZI-IR, upon be coming energized, completes a circuit for energizing relay 2MB. passing from terminal B, through the front point of contact 4!! of relay 2HR, and the winding of relay 2MB. to terminal C. Relay 2MB, upon becoming energized, completes the stick circuit for relay ZHR passing from terminal B, through contact l3 of lever 2V, line conductor l5, contact 21 of switch W closed in the reverse position, front point of contact 33 of relay 2MB, front point of contact 39 of relay ZHR, winding of relay ZI-IR, front point of contact 32 of relay ZHR, front point of contact 33 of relay 2MB, line conductor 28, and contact 22' of lever 2V to terminal C.

When the leverman later returns lever 2V to the at position, causing relay ZHR to become deenerg'ized, an indication circuit will be completedpassing from terminal B, through the back point of contact 39 of relay 2BR, front point of contact 38-of relay ZMR, contact 21 of switch W closed in the reverse position, line conductor I5, contact 25 of lever 2V, winding of magnet M, contact 25 of lever 2V, line conductor 20, front point of contact 33 of relay'2MR, back point of contact cc of relay ZHR, and the Winding of 7 relay 2MB. to terminal C.

of contact 29 of relay AHR, front point of con- It will be noted that the control circuits traced for relay ll-IR include a back contact of relay ZHR. A positive cross occurring on the pick-up circuit for relay ZHR between contact 21 of switch and contact 33 of relay ZMR, while contact 2"! is closed in the normal position, would tend to clear signal 2 if lever 2V were then moved to the r position. Because of the back contact of relay ZHR in the circuits for relay 4HR, relay l-IR would become deenergized, so that only the low speed signal 2 would be cleared.

With the arrangementshown in Fig. 2, neither of the line control conductors I5 and 20 is connected with terminal C while lever 2V is in the n position and the HR and MR relays are deenergized. This is an advantage from the standpoint of cross protection.

Fig. 3 diifers from Fig. 2 in using only one slow release indication relay 24MR instead of the two indication relays ZMR and 4MB shown in Fig. 2.

The pick-up circuit for relay ll-IR here passes from terminal B, through contact l3 of lever 2V, line conductor [5, contact 21 of switch l closed in the normal position, back point of contact 4| of relay 24MR, winding of relay GHR, back point of contact 46 of relay 24MR, line conductor 2B, and contact 22 of lever 2V to terminal 0. Relay -4HR,upon becoming energized,-

completes a circuit for energizing relay 24MR, passing from terminal B, through the front point of contact 41 of relay 4HR, and the Winding of relay '24MR to terminal C. Relay 2-4MR, upon becoming energized, completes a stick circuit for relay 4I-IR, passing from terminal B, through contact I3 of lever 2V, line conductor i5, contact 21 of switch I closed in the normal position, front point of contact 4| of relay 2-4MR, back point of contact 42 of relay 2HR, front point of contact 43 of relay 4HR, winding of relay 4I-IR, front point of contact 44 of relay iHR, back point of contact 45 of relay 2I-IR, front point of contact 46 of relay 24MR, line conductor 20, and contact 22 of lever 2V to terminal C.

With relay 4I-IR energized, the arm of signal 4 will be operated to the proceed position. As soon as the arm of signal 4 leaves the stop position, contact 36-3'| of signal 4 will become closed, thereby completing a second circuit for energizing relay 24MR, passing from terminal B, through contact 36-3! of signal 4, and the winding of relay 2-4MR to terminal C.

When the leverman later returns lever 2V to the 01 position, causing relay 4HR to become deenergized, an indication circuit will be completed when the arm of signal 4 reaches the stop position, passing from terminal B, through the back points of contacts 4'! and 48 of relays 4I-IR and 2BR, respectively, front point of contact 4| of relay 24MR, contact 21 of switch I closed in the normal position, line conductor l5, contact 25 of lever 2V, winding of magnet M, contact 26 of lever 2V, line conductor 20, front point of contact 46 of relay 2-4MR, back points of contacts 45 and 44 of relays 2HR and 4HR, respectively, contact 3! of signal 4, and the winding of relay 24MR to terminal C.

The pick-up circuit for relay 2HR in Fig. 3 passes from terminal B, through contact I3 of lever 2V, line conductor l5, contact 21 of switch I closed in the reverse position, back point of contact 49 of relay 2-4MR, winding of relay ZHR, back point of contact 46 of relay 2-4MR, line conductor 26, and contact 22 of lever 2V to terminal C. Relay 2I-IR, upon becoming energized, completes a circuit for energizing relay 24MR, passing from terminal 3, through the back point of contact 47 of relay 4HR, front point of contact 48 of relay ZHR, and the winding of relay 2-4MR to terminal C. Relay 2-4MR, upon becoming energized, completes a stick circuit for relay 2HR, passing from terminal B, through contact l3 of lever 2V, line conductor l5, contact 21 of switch I closed in the reverse position, front point of contact 49 of relay 24MR, back point of contact 43 of relay 4I-IR, front point of contact 42 of relay ZI-lR, winding of relay ZHR, front point of contact 45 of relay 2I-IR, front point of contact 46 of relay 24MR, line conductor 20, and contact 22 of lever 2V to terminal C.

When the leverman later returns lever 2V to the d position, causing relay ZI-IR to become deenergized, an indication circuit will be completed, passing from terminal B, through the back points of contacts 41 and 48 of relays 4I-IR and 2I-IR, respectively, back points of contacts 42 and 43 of relays 2I-IR and 4HR, respectively, front point of contact 49 of relay 2-4MR, contact 21 of switch I closed in the reverse position, line conductor l5, contact 25 of lever 2V, winding of magnet M, contact 26 of lever 2V, line conductor 20, front point of contact 46 of relay 2 4MB, back points of contacts 45 and 44 of relays 2HR and 4HR, respectively, contact 31 of signal 4, and the winding of relay 24MR to terminal C.

In Fig. 4, contacts l4 and 2| of relay ITPS- are included in only the signal control circuits, instead of in both the signal control and indication circuits as in Fig. 1. This arrangement provides semi-automatic stick control of signal 2, but does not provide route locking.

As previously pointed out, both semi-automatic stick control of signal 2, and route locking are provided with contacts l4 and 2| of relay ITPS located as shown in Fig. 1.

In Fig. 5, contacts l4 and 2| of relay I'IPS are omitted, and a contact 50 of relay ITPS is added in the circuit for indication magnet M. This arrangement, therefore, provides route locking, but does not provide semi-automatic stick control of the signals.

Although I have herein shown and described only a few forms of railway signal control and indication 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.

Having thus described my invention, what I claim is:

1. In control and indication apparatus for a railway signal, including manually operable control contact means and manually operable indication contact means, and also including an indication device and a control relay; the combination comprising, a slow release indication relay, a pick-up circuit for said control relay controlled by said control contact means and by a back contact of said indication relay, a stick circuit for said control relay controlled by said control contact means, a pick-up circuit for said indication relay controlled by a front contact of said control relay, and an indication circuit controlled by said control relay in the deenergized condition and by a front contact of said indication relay and also by said indication contact means for energizing said indication device and for retaining said indication relay in an energized condition.

2. In control and indication apparatus for a railway signal Which governs trafiic movements into a given stretch of railway track, including a manually operable control device having a control position and an indication position, and also including an indication device and a control relay; the combination comprising, a slow release indication relay, 2. track stick relay, a pick-up and a stick circuit for said track stick relay each of which is normally energized but each becoming deenergized in response to a train entering said given stretch of railway track, a contact of said control device included in the pick-up circuit for said track stick relay and closed if said control device is in said indication position but open if said control device is in said control position, a pick-up and a stick circuit for said control relay each controlled by a front contact of said track stick relay and by said control device in its control position and the pick-up circuit also controlled by a back contact of said indication relay, a pick-up circuit for said indication relay controlled by a front contact of said control relay, and an indication circuit controlled by said control relay in the deenergized conditionv and by front contacts of said indication and-track stick relays and also by said control device in the said control and indication contact means cated at a control point; the combination comprising, a control relay and a slow release indication relay at a signal location, a pair of conductors extending between said control point and said signal location, a train responsive relay which is normally energized'but which becomes deenergized in response to a train entering said given stretch of railway track, a pick-up and a stick circuit for said control relay each controlled by a front contact of said train responsive relay and by said control contact means and the pickup circuit also controlled by-a back contact of said indication relay, a pick-up circuit for said indication relay controlled by a front contact of said control relay, an indication circuit including said pair of conductors and controlled by said control relay in the deenergized condition and by front contacts of said indication and train responsive relays and also by said indication contact means for energizing said indication device and for retaining said indication relay in an energized condition, and an auxiliary circuit path closed at the control point across said pair of conductors by a back contact of said train responsive relay.

4. In control and indication apparatus for a railway signal which governs traflic movements into a given stretch of railway track, including manually operable control contact means and manually operable indication contact means, and also including an indication device and a control relay; the combination comprising, a slow release indication relay, a train responsive relay which is normally energized but which becomes deenergized in response to a train entering said given stretch of railway track, a pick-up and a stick circuit for said control relay each controlled by a front contact of said train responsive relay and by said control contact means and the pickup circuit also controlled by a back contact of said indication relay, a pick-up circuit for said indication relay controlled by a front contact of said control relay, and an indication circuit controlled by said control relay in the deenergized condition and by front contacts of said indication and train responsive relays and also by said indication contact means for energizing said indication device and for retaining said indication relay in an energized condition.

5. In control and indication apparatus for a railway signal which governs traffic movements into a given stretch of railway track, including manually operable control contact means and manually operable indication contact means, and also including an indication device and a control relay; the combination comprising, a slow release indication relay, a train responsive relay which is normally energized but which becomes deenergized in response to a train entering said given stretch of railway track, a pick-up and a stick circuit for said control relay each con trolled by said control contact means and the pick-up circuit also controlled by said indication relay in its deenergized condition, a pick-up circuit for said indication relay controlled by a front contact ofsaid control relay,.and an indication circuit controlled by said control relay'in'lthe deenergized condition and by front contactszof said indication and train responsive relays and also by said indication contactmeans forenergizing said indication device and for retaining said indication relay in an energized condition.

6. In control and'indication apparatus for a railway signal which governs traffic movements into a given stretch of railway track, including manually operable control contact means and manually operable indication contact means, and also including an indication device and a control relay; the combination comprising, a slow release indication relay, a train responsive relay which is normally energized but which becomes deenergized in response to a train enteringsaid given stretch of railway track, a pick-up and a stick circuit for said control relay each controlled by a front contact of said trainresponsiverelay and by said control contact means andwthe'pickup circuit also controlled by aback contact of said indication relay, a pick-up circuit for said indication relay controlled by afront contact of said control relay, and;an indicationcircuitycontrolled by said control relay in the deenergized condition and by a front contact of said indication relay and also by said indication contact means for energizing said indication device and for retaining said indication relay in an energized condition.

7. In control and indication apparatus for a railway signal, including manually operable control contact means and manually operable indication contact means, and also including an indication device and a control relay; the combination comprising, a slow release indication relay, a pick-up circuit for said control relay controlled by said control contact means and by a back contact of said indication relay, a stick circuit for said control relay controlled by said control contact means and by said indication relay in the energized condition, a pick-up circuit for said indication relay controlled by a front contact of said control relay, and an indication circuit controlled by said control relay in the deenergized condition and by a front contact of said indication relay and also by said indication contact means for energizing said indication device and for retaining said indication relay in an energized condition.

8. In control and indication apparatus for a railway signal, including a manually operable control device having a control position and an indication position, and also including an indication device and a control relay; the combination comprising, a slow release indication relay, a circuit closed in response to operation of said control device to its control position and controlled by said indication relay in the deenergized condition for energizing said control relay, a circuit controlled by a front contact of said control relay for energizing said indication relay, and an indication circuit controlled by said.con-' trol relay in the deenergized condition and by a front contact of said indication relay and also by said control device in its indication position for energizing said indication device and retainitng said indication relay in an energized condiion.

9. In control and indication apparatus for a railway signal, including manually operable control contact means and manually operable indication contact means, and also including an indication device and a control relay; the combination comprising, a slow release indication relay,

a train responsive relay which is normally energized but which becomes deenergized in response to a train passing said signal, a circuit closed in response to the closing of said control contact means if said indication relay is deenergized and controlled by a front contact of said train responsive relay for energizing said signal control relay, a pick-up circuit for said indication relay controlled by a front contact of said control relay, a'stick circuit for said indication relay controlled by back contacts of said control and train responsive relays, and an indication circuit controlled by said control relay in the deenergized condition and by front contacts of said indication) and train responsive relays and also by the closing of said indication contact means for energizing said indication device and retaining said indication relay in an energized condition.

10. In control and indication apparatus for a railway signal, including a manually controlled signal control relay and an indication device; the combination comprising. a slow release indication relay. a back contact of said indication relay included in the control means for said signal control relay. a circuit controlled by a front contact of said signal control relay for energizin said indication relay. and an indication circuit controlled by said signal control relay in the deenergized condition and by a front contact of said indication relay for energizing said indication device and for retaining said indication relay in an energized condition.

11. In control and indication apparatus for a railway signal, including a control relay and an indication device; the combination comprising, a slow release indication relay, a manually controlled circuit also controlled by a back contact of said indication relay for energizing said control relay, a manually controlled stick circuit for retaining said control relay in an energized condition, a pick-up circuit for said indication relay controlled by a front contact of said control relay, and an indication circuit controlled by said control relay in the deenergized condition and by a front contact of saidindication relay for energizing said indication device and for retaining said indication relay in an energized condition,

HENRY S. YOUNG.

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