US2768287A - Railway track switch controlling apparatus - Google Patents

Description

Oct. 23, 1956 F. T. PAscoE RAILWAY TRACK SWITCH CONTROLLING APPARATUS Filed Dec. 24, 1952 INVENTOR.

Frank 7. Paseoe Lu km HIS ATTOIUVEY United States Patent RAILWAY TRACK SWITCH CONTROLLING APPARATUS Frank T. Pascoe, Scott Township, Allegheny County, Pa.,

assignor to Westinghouse Air Brake Company, Wilmerding, Pa., a corporation of Pennsylvania Application December 24 1959, Serial No. 327,770

1 Claim. (Cl. 246-219) having a neutral armature and a polar armature, is comr monly employed. Traffic movements over the corresponding switch are governed by signals for the routes in which the switch is included.

A traffic responsive relay, such, for example, as a track relay associated with the switch, is normally energized, but becomes deenergized in response to a train adjacent the switch, on a route in which the switch is included. A

switch locking relay is controlled to be energized, for

closing a front contact, only if the traffic responsive relay is energized, and only if each of the signals which directs trafic movements over the switch is controlled for displaying a stop indication.

It would obviously be unsafe for the switch to be moved from either of its extreme positions to the other, while the associated switch locking relay is deenergized either because ofa train adjacent the switch on a route in which the switch is included, or because a signal is controlled for displaying a proceed indication for directing a trafiic movement to be made over the switch. Accordingly, in

order to prevent movement of the switch from being manually effected from a remote control point while either of those conditions exists, it has been common practice to include front contacts of the switch locking relay in the normal and reverse control circuits for the polarized switch control relay, as shown, for example, in Fig. l of 'Letters Patent of the United States No. 2,026,810, granted January 7, 1936, to H. S. Young, for Railway Track Switch Controlling Apparatus, in which front contacts 9 and 10 of the switch locking relay R are included in the normal and reverse control circuits for the polarized switch control relay in. It has also been common practice to include back points of contacts of the switch locking relay in normal and reverse stick circuits for the polarized switch control relay, as also shown in the Young patent mentioned, in which back points of contacts 9 and 10 of relay R are included in normal and reverse stick circuits for relay in.

With the arrangement shown in the Young patent, energization of the polarized relay m by current of normal and reverse polarities can be effected by the manually operable lever k, at a remote control point, only while the switch locking relay R is energized. When relay R becomes deenergized, however, a stick circuit including front contact 19 of relay m becomes completed for retaining relay in energized by current of the polarity by which relay m was last energized before deenergization of relay R took place. Therefore, although relay R is deenergized, normal switch control magnet nn or reverse switch control magnet rr will be retained in the energized condition by a cir-' cuit which includes neutral contact 21 of the relay m and polar contact 22 closed in the normal or the reverse position, respectively.

Since either normal control magnet an or reverse control magnet rr is thus retained energized while relay R is deenergized, it follows that, if the switch should become misplaced by some external means such, for example, as dragging equipment on a train, while relay R is deener gized, the switch mechanism will act to return the switch to the position from which it has been misplaced, if the lock control magnet, not shown in the Young patent, is also energized. Such an arrangement for returning the switch to the position from which it has become misplaced by external means is known as the restoring feature.

If, while relay R is deenergized, relay m should become deenergized accidentally is some way such, for example, as by a temporary failure of the source of current for energizing this relay, or by an accidental temporary opening of one of the contacts 9 and 10 of relay R, at the back point, or of one of the contacts l8, l9 and 20 of relay m, in the normal or the reverse stick circuit for relay m, contact 19 would remain open, and relay m could not become energized again until after relay R became energized again. The restoring feature would therefore be lost, and would remain lost as long as relay R remained in the deenergized condition. Consequently, if, in the meantime, the switch should become misplaced, the switch mechanism would not return it to the position from which it became misplaced.

An object of my invention is therefore the provision of a control arrangement, for an electro-pneumatic switch mechanism, for example, in which, if the restoring feature should become lost while the switch locking relay is deenergized, it can be regained while the switch locking relay is still deenergized;

A feature of my invention for attaining this object is the provision of a normal switch control relay and a reverse switch control relay, each of which is controlled to become energized when the switch locking relay becomes deenergized while the switch is in a corresponding position.

Another feature of my invention is the provision, for each of the normal and reverse switch control relays, of apickup circuit which, if the corresponding relay should become deenergized accidentally while the switch locking relay is deenergized, can become closed for again energizing the corresponding relay while the switch locking relay is still deenergized.

My invention, as indicated by the foregoing para graphs concerning its object and features, is in railway track switch controlling apparatus in which the restoring feature, for effecting restoration of a switch to a position from which it has become misplaced While a corresponding switch locking relay is deenergized, is provided by normal and reverse switch control means, such, for example, as a normal and a reverse switch control relay, in addition to a polar switch control relay. Each of these normal and reverse switch control relays has a pickup circuit which becomes closed when the switch locking relay becomes deenergized while the switch is in a corresponding position, and has a stick circuit controlled by the switch locking relay in the deenergized condition. If either of the normal and reverse switch control relays should become falsely deenergized, such, for example, as due to a momentary failure of its energizing current while the switch locking relay is deenergized and the switch is in a corresponding position, it will again become energized, while the switch locking relay is still deenergized, as soon as the failure of its energizing current ends.

If the switch should become accidentally misplaced while the switch locking relay is deenergized, restoration of the switch to the normal or the reverse position from which it became misplaced will be eifected by means including a front contact of the normal or the reverse switch control relay, respectively, and a back contact of the switch locking relay.

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

The accompanying drawing is a diagrammatic view showing one form of apparatus embodying my invention for an electropneumatic switch mechanism, in which a polar switch control relay, designated by the reference character WSR, is energized by manually controllable normal and reverse circuits which are also controlled by a switch locking relay, designated by the reference character LR, in the energized condition; in which a normal switch control relay, designated by the reference character NRSR, and a reverse switch control relay, designated by the reference character RRSR, are controlled to become energized when the switch locking relay LR becomes deenergized while the switch is in a corresponding position; and in which normal and reverse control magnets, designated by the reference characters A and B, respectively, are controlled by relays NRSR and RRSR, respectively, for providing the restoring feature for the switch while the switch locking relay LR is deenergized.

Referring further to the drawing, a railway track switch, designated by the reference character W, is shown in a normal position in a route over a main track which is designated by the reference character T. An auxiliary track, designated by the reference character I, is connected by switch W in its reverse position with main track T in a second route.

Tracks T and t are divided by insulated joints 1 to form a switch section a-b. Section a--b is provided with traflic responsive means or safety control means such, for example, as a track relay TR connected across the rails adjacent one end of section ab, and energized by current from a suitable source such, for example, as a battery 2, connected across the rails adjacent the opposite end of section ab.

A signal, designated by the reference character S, is shown for governing traffic movements over a route which includes switch W. Signal S may be of any suitable design such, for example, as the well known color light type, comprising a yellow light unit, designated by the reference character Y, and a red light unit, desig nated by the reference character R.

Signal S may be controlled in any suitable manner for displaying a yellow proceed indication for directing a traflic movement over a route which includes switch W, and therefore for also directing a traflic movement over switch W. As shown in the drawing, the control means for signal S includes a manually operable signal control lever, designated by the reference character SV, which may be located at a remote control point such, for example, as an interlocking tower or a dispatchers ofiice. Lever SV has a normal position n, and a control position f to the left, and also a control position r to the right, as shown in the drawing.

An energizing circuit for a signal control relay, designated by the reference character HR, is controlled by means including a contact 24 of lever SV, which is closed while lever SV is in its r position, and a contact 25 of relay TR. Circuits for controlling signal S to display the yellow proceed indication or the red stop indication are controlled by means including front and back points, respectively, of a contact 3 of relay HR.

I shall assume that traffic movements toward the right, as shown in the drawing, are in the eastbound directhe n position.

reverse polar contact 20 of relay WSR.

tion. Signal S therefore controls eastbound traffic movements. I

Switch W is operable to a normal position, in which it is shown in the drawing, and also to the opposite or reverse position, by a switch mechanism, designated by the reference character M, which may be of the wellknown electropneumatic type having normal, reverse and lock control magnets, designated by the reference characters A, E and L, respectively.

A switch circuit controller, designated by the reference character WC and comprising contacts 17, 19 and 23, is operated in conjunction with switch W. Contact 17 is closed while switch W is in the normal position, and is open while switch W is in any other position. Contact 19 is open in all positions of switch W except the reverse position, but becomes closed when switch W reaches the reverse position. Contact 23 is open while switch W is in either the normal or the reverse extreme position, but is closed while switch W is in any position between its normal and reverse extreme positions.

Normal and reverse switch control magnets A and E', respectively, for switch W, are controlled by a polar contact 14 of relay WSR in its normal and reverse positions, respectively, and by front contacts of switch locking relay LR, for effecting the usual operations of switch W between its normal and reverse positions. Lock control magnet L is controlled by a circuit which includes back contacts of normal and reverse switch indication relays, designated by the reference characters NWCR and RWCR, respectively, and is also controlled by a branch circuit which includes contact 23 of switch W.

Polar switch control relay WSR comprises a normal control magnet c and a reverse control magnet d, and is of the type in which the polar contacts, when the relay becomes deenergized, remain closed in the position to which they were last previously operated. As shown in the drawing, manual control of relay WSR is effected by a manually operable switch control lever designated by the reference character WV, having a normal position it and a reverse position r.

Contacts operated by levers SV and WV are represented on the drawing by circles in which are placed reference characters to show the positions of the respective levers in which the contacts are closed. Contact 10 of lever WV, for example, shown in the normal control circuit for relay WSR, is closed only while lever WV is in Contact 12 of lever WV is closed only while lever WV is in the r position.

Each of the relays NRSR and RRSR is controlled by a back contact 26 of the switch locking relay LR. Relay NRSR is also controlled by a front contact 28 of relay NWCR, and by the back point of a contact 27 of relay RRSR. Relay RRSR is also controlled by a front contact 31 of relay RWCR, and by the back point of a contact 30 of relay NRSR. The use of the back point of contact 27 of relay RRSR in the circuits for relay NRSR, and of the back point of contact 30 of relay NRSR in the circuits for relay RRSR are not necessary for the usual operation of the apparatus, but may provide some protection against false operation of the apparatus.

Relay NWCR is controlled by contact 17 of switch W, and by a normal polar contact 18 of relay WSR. Relay RWCR is controlled by contact 19 of switch W, and by a It follows that each of the relays NWCR and RWCR will become energized only when the polar contacts of relay WSR arein positions corresponding with the position of switch W.

An approach locking relay, designated by the reference character ASR, is controlled by relays HR and TR, and by a time element device designated by the reference character TE. Time element device TB is in turn controlled by back contacts of relays HR and ASR, and controls a contact 6 which is normally open but which -5 bec m l sed 1 1 t e a e s a mes a ed od at time after time element device TE becomes energized.

..S.witch locking relay LR is fiqutrolled by front contacts ,of relays TR and ASR, and is therefore energized only when these relays are both energized.

It follows that relay LR is energized only while there is no train adjacent switch W on a route which includes switchW, and only while signal S is controlled to display a ,stop indication. When a train occupies section a--b adjacent switch W, or when signal S is controlled by relay HR to display a proceed indication for directing a traflic movement over switch W, relay LR will be deenergized, and therefore the control circuits for relay WSR will be open at contacts 11 and 13 of relay LR.

The Various control circuits shown in the drawing may be supplied With energizing current from any suitable source such, for example, as the battery Q having terminals designated by the reference characters B and N.

Having described, in general, the arrangement and control of the apparatus shown by the accompanying drawing, I shall now describe its operation in detail.

As shown by the drawing, all parts of the apparatus are in the normal condition, that is, switch W is in its normal position; signal S is controlled to display a stop indication; track section ab is unoccupied, and therefore track relay TR is energized; each of the levers SV and WV is in its n position; relays ASR, LR and NWCR, normal switch control magnet A and normal control winding 0 of relay WSR are energized; and relays HR, NRSR, RRSR and RWCR, reverse switch control magnet E and lock control magnet L of switch mechanism M, and reverse control winding d of relay WSR are all deenergized.

The circuit by which lamp R of signal S is energized for displaying the red or stop indication passes from terminal B, through the back point of contact 3 of relay HR, and lamp R to terminal N.

Relay ASR is energized by a stick circuit passing from terminal B, through contact 4 of relay HR, front point of contact 5 of relay ASR, and the winding of relay ASR to terminal N.

Relay LR is energized by a circuit passing from terminal B, through contacts 8 and 9 of relays ASR and TR, respectively, and the winding of relay LR to terminal N. A Normal control winding 0 of relay WSR is energized by a circuit passing from terminal B, through contact 10 of lever WV, contact 11 of relay LR, and winding 0 of relay WSR to terminal N.

The circuit by which normal switch control magnet A is energized passes from terminal B, through contact 14 of relay WSR closed in the normal, or left-hand position as shown in the drawing, contact 15 of relay LR, and the winding of control magnet A to terminal N.

The circuit by which relay NWCR is energized passes from terminal B, through contact 17 of switch W, contact 18 of relay WSR, and the winding of relay NWCR to terminal N.

I shall assume that a leverman or dispatcher desires to move switch W to the reverse position. He will therefore move lever WV to the r position, deenergizing normal control winding c of relay WSR. When lever WV reaches the r position, the reverse control winding d of relay WSR will become energized by its circuit pass ing from terminal B, through contact 12 of lever WV, contact 13 of relay LR, and reverse control winding d of relay WSR to terminal N.

Relay WSR will then move its polar contacts to the reverse position, thereby deenergizing relay NWCR and control magnet A. With relay NWCR deenergized, lock control magnet L will become energized by a circuit passing from terminal B, through contacts 21 and 22 of relays RWCR and NWCR, respectively, and the winding of lock control magnet L to terminal N.

Contact 14 of relay WSR, upon becoming closed in the reverse position, will complete a circuit for energizing arenas? 6 reverse switch control magnet E, this circuit passing from terminal B, through contact 14 of relay WSR in the re.- verse position, contact 16 of relay LR, and the winding of control magnet E to terminal N. With lock control magnet L and reverse control magnet E both energized, mechanism M will effect the operation of switch W to its reverse position. While switch W is between its normal and reverse positions during its movement to the reverse position, the branch circuit for lock control magnet L will be closed passing from terminal B, through contact 23 of switch W, and the Winding of lock magnet L to terminal N.

When switch W reaches the reverse position, contact 19 of switch W will complete the circuit for enengizing relay RWCR, this circuit passing from terminal B, through contact 19 of switch W, contact 20 of relay WSR, and the winding of relay RWCR to terminal N.

When the leverman or dispatcher desires to retuurn switch W to its normal position, he will return lever WV to its n position, thereby deenergizing reverse control winding of of relay WSR. When lever WV reaches the 11 position, normal control winding c of relay WSR will again be energized by its circuit previously traced.

Relay WSR will then return its polar contacts to the normal position, thereby deenergizing relay RWCR. Lock control magnet L will now again be energized by its circuit previously traced through contacts 21 and 22 of relays RWCR and NWCR, respectively On account of contact 14- of relay WSR now occupying the normal position, reverse control magnet E will be deenergized, and normal control magnet Awill again be energized by its circuit previously traced. With lock control magnet L and normal control magnet A now energized, mechanism M will effect operation of switch W back to its normal position.

When switch W reaches the normal position, its contact 17 will again complete the circuit previously traced for relay NWCR, and relay NWCR will therefore again be energized. Relay NWCR, upon becoming energized, will open its contact 22, thereby deenergizing lock control magnet L.

I shall now assume that, with all parts of the apparatus again in the normal condition, an eastbound train is to move over section a-b. A leverman or dispatcher will therefore move lever SV to its r position.

When lever SV reaches the r position, signal control relay HR will be energized by a circuit passing from terminal B, through contact 24 of lever SV, contact 25 of relay TR, and the winding of relay HR to terminal N. Relay HR, upon becoming energized, will open its contact 3 at the back point, thereby extinguishing lamp R of signal S, and will then complete a circuit for lighting lamp Y of signal S, passing from terminal B, through the front point of contact 3 of relay HR, and lamp Y to terminal N.

Relay HR, upon becoming energized, also opens its contact 4, thereby deenergizing relay ASR. Contact 8 of relay ASR will then open the circuit previously traced for relay LR, causing relay LR to be deenergized. Relay LR, upon becoming deenergized, will open, at its contact 11, the circuit previously traced for normal control winding 0 of relay WSR, and will also open, at its contact 15, the circuit previously traced for normal control magnet A, thereby causing relay WSR and normal control magnet A to be deenergized.

Since relay WSR is of the type which, upon becoming deenergized, retains its polar contacts closed in the position to which they were last previously operated, contact 18 of relay WSR will remain closed in the circuit previously traced for relay NWCR, and therefore relay NWCR will remain energized.

With relay LR deenergized, relay NRSR will become energized by a pickup circuit passing from terminal B, through contact as of relay LR, back point of contact 27' of relay RRSR, contact 28 of relay NWCR, and the winding of relay NRSR to terminal N. Relay NRSR,

upon becoming energized by its pickup circuit, will complete a stick circuit which is the same as the pickup circuit just traced except that it includes contact 253 of relay NRSR instead of contact 28 of relay NWCR. Relay NRSR, upon becoming energized, will complete a circuit for energizing normal control magnet A, this circuit passing from terminal B, through contact 26 of relay LR, front point of contact 30 of relay NRSR, and the winding of normal control magnet A to terminal N. In this way, the restoring feature is provided for switch W while relay LR is deenergized.

If the leverman or dispatcher should decide to hold the train at signal S, he will return lever SV to its 11 position, thereby deenergizing relay HR. With relay HR deenergized, lamp Y of signal S will be extinguished, and lamp R of this signal will again be lighted by its current previously traced.

With relay HR deenengized, a circuit will be completed for energizing the time element device TE, this circuit passing from terminal B, through contact 4 of relay HR, back point of contact 5 of relay ASR, and the control element of time element device T E to terminal N. Upon the lapse of a measured period of time, device TE will close its contact 6, thereby completing a pickup circuit for relay ASR, this circuit passing from terminal B, through contact 4 of relay HR, contact 6 of time element device TE, and the winding of relay ASR to terminal N. Relay ASR, upon thus becoming energized, will close its contact 5 at the front point, thereby again completing its stick circuit previously traced. With relay ASR energized, relay LR will now again be energized by its circuit previously traced.

With relay LR energized, the circuits for relay NRSR and normal control magnet A will be opened at contact 26 of relay LR. Normal control magnet A will now again be energized by its circuit previously traced through contact 14 of relay WSR in the normal position and contact of relay LR.

I shall assume that, with all parts of the apparatus again in the normal condition, the leverman or dispatcher again controls signal S to display the yellow proceed indication, as before, for authorizing an eastbound train to proceed over section ab. When the train enters section ab, relay TR will become deenergized, thereby opening, at its contact 25, the circuit previously traced for relay HR, causing relay HR to become deenergized. Lamp Y of signal S will therefore be extinguished, and lamp R of this signal will again be lighted. With relay TR deenergized, contact 9 of this relay will open at a second point, the circuit for relay LR.

With contact 7 of relay TR now closed, a second pickup circuit will be completed for relay ASR, which is the same as the first pickup circuit traced for this relay, except that it includes contact 7 of relay TR instead of contact 6 of time element device TE. Relay ASR, upon becoming energized, will again close its contact 8 in the circuit for relay LR, which, however, remains open at contact 9 of relay TR. Relay LR will therefore remain deenergized.

I shall next assume that, while relay LR is still deenergized due to a train on section a-b, relay NRSR becomes accidentally deenergized, and therefore the restoring feature is lost. I shall assume further, that the cause of the accidental deenergization of relay NRSR is then removed while relay LR is still deenergized. Relay NRSR will then again be energized by its circuit previously traced through contacts 26, 27 and 28 of relays LR, RRSR and NWCR, respectively. In this way, the restoring feature will be regained while relay LR'is still deenergized.

I shall now assume that, while relay LR is still deenergized, switch W becomes misplaced, so that it occupies some intermediate point between its normal and reverse positions. Contact 23 of switch W will therefore be closed, completing the branch circuit for lock control magnet L. When relay NWCR becomes deenergized by the opening of contact 17 of switch W, the control circuit for lock control magnet L passing through contacts 21 and 22 of relays RWCR and NWCR, respectively, will also again be closed. With normal control magnet A now energized by its circuit which includes contact 26 of relay LR and the front point of contact 30 of relay NRSR, and with lock control magnet also energized, mechanism M will effect the return of switch W to its normal position. l

I have described a few typical examples of the operation of apparatus embodying my invention. It is believed that, in view of such description, any other possible operation of the apparatus can be readily traced by referring to the accompanying drawing.

Although I have herein shown 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 claim without departing from the spirit and scope of my invention.

Having thus described my invention, what I claim is:

In apparatus for controlling a railway track switch embodying a switch locking relay which is controlled by trafiic responsive means and by signal control means to be energized if and only if a portion of track in which said switch is located is unoccupied and a signal for governing traffic movements over said switch is controlled to indicate stop, the combination comprising, a polar switch control relay, manually controllable meanscontrolled also by said switch locking relay for energizing said polar switch control relay by current of normal or reverse polarity only if said switch locking relay is energized, means controlled by said polar switch control relay and by said switch locking relay in the energized condition for effecting operation of said switch to normal and reverse positions in response to energization of said polar switch control relay by current of normal or reverse polarity respectively, a normal switch control relay energized by means controlled by said switch locking relay in the deenergized condition and by said switch in the normal position and then retained in the energized condition by means controlled by said switch locking relay in the deenergized condition, a reverse switch control relay energized by means controlled by said switch locking relay in the deenergized condition and by said switch in the reverse position and then retained in the energized condition by means controlled by said switch locking relay in the deenergized condition, and means controlled by said normal and reverse switch control relays and by said switch for restoring said switch to the corresponding position if said switch becomes misplaced by external means.

References Cited in the file of this patent UNITED STATES PATENTS 1,942,788 Wight Jan. 9, 1934 2,009,187 Phinney July 23, 1935 2,183,694 Rees Dec. 19, 1939 2,604,581 Johanek July 22, 1952

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