US2132139A - Railway traffic controlling system - Google Patents

Description

Gd. 4, mm s. N. WIGHT RAILWAY TRAFFIC CONTROLLING SYSTEM Filed July 51, 1934 lillllllllllQlW llllll II Patented Oct. 4, 1938 UNITED STATES 2,132,139 RAILWAY TRAFFIC CONTROLLING SYSTEM Sedgwick N. Wight,

General Railway Rochester, N. Y., assignor to Signal Company, Rochester,

Application July 31, 1934, Serial No. 737,780

Claims.

' This invention relates to traific controlling systems for railroads and it more particularly pertains to a system for the remote control of power-operated switch machines.

In a system of remote control of power-operated switch machines for use in connection with terminals, interlocking plants and centralized trafiic controlling systems, it is desirable to obtain the various controls and indications required for efiicient operation of a switch machine over a minimum number of line wires between the tower or control office for each switch. Therefore one object of the present invention is to provide a simple and reliable arrangement of line circuits and relays so related that several difierent distinctive controlling conditions may be transmitted or communicated instantaneously in response to the energization or deenergization of the line circuits.

More specifically, this invention provides for the transmission over a single polarized line circuit of the controls required for a power-operated switch machine and the provision in connection with the approach and detector locking usually employed with power-operated switch machines, of an improved circuit arrangement for requiring the movement of the control lever at the time the approach and detector locking is not effective in order to operate the switch machine so that such switch machine will not operate after a train movement over the switch until the op-- erator shifts the control lever.

Various other characteristic features and advantages of the invention will be in part apparent and in part specifically pointed out as the description progresses.

In describing the invention in detail reference will be made to the accompanying drawing, which is a diagrammatic illustration of one specific embodiment of the present invention as applied to the control of traflic over a single railroad track switch.

Although the traffic controlling system of the present invention may be applied to various track layouts involving conflicting and non-conflicting routes and various other conditions encountered in practice, it has been specifically illustrated as applied to asingle track switch and preferably associated with an automatic block signal system of the type for example as disclosed in my prior patent, No. 2,082,436 dated June 1, 1937. With reference to the accompanying drawing the railroad track switch TS is illustrated as connecting the rails 3 of a main track to the rails 4 of a diverging or turn-out track. This track switch TS is operated by a power driven switch machine SM which may be of any suitable type, such for example as disclosed in the patent to W. K. Howe, No. 1,66,903, dated September 4, 1923. This switch machine may be provided with a dual 5 control selector to permit hand operation of the track switch such as shown for example in the patent to W. K. Howe, No. 1,852,573 dated April 5, 1932.

The main track adjacent the track switch TS and a'portion of the diverging track to the fouling point comprises a detector track circuit of the closed circuit type with the usual track battery '5 and track relay T, which detector track circuit is insulated from the rest of the track layout by the usual insulated joints.

Trafiic over the track switch in an eastbound direction is governed by signals I and men the main track and on to the turn-out track respectively. Trafiic over the track switch in a westbound direction is governed by signals 2' and 2D on the main track and off the turn-out track respectively.

The track switch and the switch machine are preferably provided with point detector contacts of some suitable type such for example as disclosed in the patent to C. S. Bushnell, 1,517,236, dated November 25, 1924. These point detector contacts are'employed to energize a switch position repeating relay of the usual polar neutral type'in accordance with the position and locked or unlocked condition of the track switch but since this particular feature forms no part of the present invention it has been omitted from the drawing for the sake of simplicity.

A polar neutral relay WZ preferably of the magnetic stick type is governed from the control ofiice over a suitable polarized line ci-rcuitincludi'ng line conductor 6. The polar contact 1 of the'relay, when operated to one or the other of its extreme positions, serves to operate the switch machine to normal or reverse extreme locked positions. Since this portion 6f the operation of the system is immaterial for an understanding of the present invention'it is only indicated by dotted line 8 leading from contact 1 to the switch machine.

A time element device TE, a neutral stick relay S and a neutral lock relay L are associated with thetra'ck relay T and with relay "M in such a manner as to provide approach locking for track switch TS with suitable time release control, all of which has been more completely disclosed in the prior patent to R. M. Phinney, Patent No. 2,082,741, dated June 1 ,1937. A neutral relay M position when it is lighted.

is energized whenever all signals are at stop and deenergized when any one of the signals is cleared.

In the control office a suitable control machine is provided with the usual miniature track diagram having control levers and indicators advantageously located thereon. For convenience in describing the present invention only the switch machine control lever SML and signal control lever SGL for governing track switch TS and the associated signals have been shown. Lever SML is preferably of the two-position quick acting type operating its contacts to either the extreme normal or reverse position. In other words, contacts 9 and ill of lever SML snap from one position to the other in response to the actuation of lever SML irrespective of whether this lever is quickly or slowly operated.

The control of the signals by lever SGL is merely indicated by dotted line l6 since the detailed operation of such control is immaterial.

A look repeating relay LP is provided in the control office, which relay is of the retained neutral polar type, that is, its polar contacts are operated to the right when potential is applied to the line circuit 6 from the control ofiice battery and to the left' when potential is applied to this line circuit from the control ofiice battery. The neutral contacts assume picked up positions when the winding of this relay is energized and the operation distinguishes from the usual neutral polar type relay in that the contacts are not dropped when the current is suddenly reversed in the winding of the relay. This is indicated by the shaded portion of the relay on the drawing. Such operation of' the LP relay may'be' obtained in any approved'manner, one such type of relay being disclosed in the patent to F. C. Larson, No. 1,852,210, issued April 5, 1932.

To simplify the illustrations the circuits are illustrated in a conventional manner with the symbol indicating the'p'ositive terminal and the symbol indicating the negative terminal of a suitable battery or other'source of current, with the circuits to which these terminals are connected having current flowing from to Symbol (B+) is associatedwith the terminal and symbol (B-) is associated with the terminal of suitable batteries or other sources of current located in the control ofiice and at the field station, each having a mid-tap (CN). In this connection it is to be understood that the terminal (CN) at thefield station is connected to the mid-tap. of the control office battery over a common return conductor which is not shown. I i I I In accordance with the present invention it is contemplated that the track adjacenttothe switch TS will in practice be providedwith track circuits, wayside signals, line circuits and the like, constituting suitable approach locking for the switch. The specific details of such approach locking circuits are immaterial to the present invention and therefore have been omitted.

Lock indicator lamp LI is provided to give the operator an indication when the switch at the associated field station is in its locked condition. This lamp serves as an indication to the operator not to move the switch machine lever to a new In the event that the lever is moved to. a new position when the lamp is lighted then the electric lock equivalent feature is effective to prevent any response to such lever actuation at the field station until the lever is returned to its former position and then actuated when the switch is unlocked.

Contacts ll, 12 and 13 are associated with signals I, 2 and 2D respectively and are included in a series circuit leading to relay M for the purpose of maintaining relay M in its picked up condition as long as all signals are at stop and for dropping relay M when any signal is cleared,

which results in opening its associated contact.

It will be understood that other details and adaptations may be incorporated in the present teristic features and functions of the system by considering the operation under certain characteristic or typical conditions.

OPERATION Normal conditions-With the detector track section unoccupied and with the switch control level SML in the position shown, the various devices, relays and circuits assume positions and conditions of energization as illustrated. Since it is assumed that theillustrated'track section is unoccupied track relay T is normally energized.

Since all signals are at stop a circuit is completed for energizing relay M which extends from contact H of signal I in its stop position, contact I? of signal 2 in'its stop position, contact E3 of signal 2D in its stop position and winding of relay M, to

Relay S is normally energized over a circuit extending from through the operating element Hi of the timing deviceTE, front contact i of relay S, winding of relay S and front contact it of relay M, to It will ,be understood that the resistance of relay S is suificiently, high to prevent the operationof the time element device over the circuit just described.

With relays T and S energized and with the time element device in its normal condition, an

' energizing circuit is closed for relay L extending from contact IQ of time element device TE, front contact of relay S, winding .of relay L and front contact 2| of relay T, to

The normal energizing circuit for relay WZ extends from (13+) in the control office, contact In of lever SML in its normal position, front contact 22 and polar contact 23 in multiple of relay LP, winding of relay LP, line conductor 6, front contact 24 of relay L, winding of relay WZ to terminal CN and thence over the common conductor (not shown) to the control office and to the midtap of the control battery. This energization of relays LP and WZ causes their polar contacts to be actuated to the right and the neutral contacts of relay LP to be picked up, all as indicated in the drawing. V

Manual control of the track; switch-It will now be assumed that the operator moves the switch machine control lever SML to its reverse dotted line position. As above mentioned contacts 9 and Ill are preferably of the snap action type.

so that the current through the winding of relay LP (which relay is slightly slow acting) is quickly reversed so that relay LP does not drop its neutral contacts. As also above mentioned this relay is of the retained neutral polar type so that the sudden reversal of current in its winding does not kick down its neutral contacts' The reversal of current effected by the actuation of lever SML to its reverse position is due to a circuit extending from (B) contact 9 in its dotted line position, front contact 25 of relay LP, winding of relay LP, line conductor 6, front contact 24 of relay L and winding of relay WZ, to CN.

Polar contact 1 of relay WZ is actuated to its left hand dotted position which energizes a circuit effective to operate the switch machine for placing the track switch in its reverse position.

The response of the track switch may be indicated to the operator by'the energization of suitable indicators from the contacts of the switch repeating relay (not shown), which relay may be provided with polar and neutral contacts to accomplish such indication, all in accordance with practices heretofore disclosed but not shown in the present disclosure because such operation is immaterial to an understanding of the present invention.

The operation involved in actuating the track switch from its reverse locked positionto its normal locked position is merely the inverse of that already described and need not be specifically pointed out. It need only be mentioned that the return of lever SML to its normal position re-, verses the current flow through relay WZ for positioning contact 7 back to its right hand position which, through the medium of switch machine SM, actuates the track switch to its normal position. During this operation the reversal of current through the winding of relay LP takes place in such rapid order that its neutral contact 22 is not dropped so that its energizing circuit is established even before contact 23 is actuated back to its right-hand position.

Manual control of signaZs.-Assuming clear trafuc conditions, either signal I or 2 may be cleared with the track switch in a normal position and either signal ID or 2D may be cleared with the track switch in a reverse position. The signals are governed in accordance with the position of signal lever SGL. When actuated to the right or to the left the operator is able to establish traific in either east or west-bound directions. As above mentioned the detailed circuits for clearing these signals is not shown but it will be understood that the series circuit including relay M is opened when any signal is cleared due to the opening of some one of the contacts H, l2 or l3.

The deenergization of relay M in response to clearing a signalopens the stick circuit of relay S at front contact 18 of relay M. This causes relay S to drop its contacts which in turn de,

energizes relay L at front contact 20. The dropping of contact 24 of relay L prevents the operator from reversing the polarity to the winding of relay WZ during any time that a signal governing traffic over the track switch is clear. The dropping of contact 24 deenergizes line conductor 6 which drops the neutral contacts of relay LP. A circuit is now closed at back contact 26 of relay LP for lighting lamp LI as an indication that the track switch is locked.

During the deenergization of conductor 6, local energy is applied to the winding of relay WZ, the polarity of which corresponds to the last polarity which actuated relay WZ over conductor 6. This holds the contacts of the W2 relay in their last operated positions during the time that its remote control circuit is opened at relay L. In this case for example, relay WZ is energized over a circuit extending from (B'+), contact 2'! of relay WZ in its right-hand position, back contact 24 of relay L and winding of relay WZ, to CN.

Since relay LP in the control office isdeenergized, the :movement of lever SML will neither effect the operation of relay WZ or relay LP. This provides the electric lock equivalent featurewhich will be later described.

Approach locking and time release-As the operator anticipates the approach of a train and sets up a particular route by clearing a signal for that route (as above explained for example) and then attempts to alter the route already established, he is prevented from operating the track switch for a predetermined time after the signals governing that route have been returned to their stop conditions. This predetermined time is measured by the time element device TE, which includes both the heating and cooling time of its thermal element as more specifically pointed out in the above mentioned prior patent, Patent No. 2,082,741.

For example, it will be assumed that the operator returns signal I to stop which results in the energization of relay M over the previously described circuit. Relay M closes a circuit extending from through the heating element of the device TE, back contact ill of relay S and front contact is of relay M to Sufficient current flows through this circuit to cause the heating element M to actuate contact l9 to its open position and to actuate contact 29 to its closed position. The opening of contact l9 maintains relay L deenergized which keeps the switch locked. The closure of contact 29 completes a pick-up circuit for relay S which extends from contact 29, winding of relay S and front contact N3 of relay M, to Relay S is then stuck up over its previously described stick circuit, which circuit now includes contact 29 in shunt of heating element M. This shunting or short circuiting of element l4 allows the time element device to cool sufliciently to again close contact 49 and to open contact 29. completes the pick-up circuit for relay L and open contact 29 removes the shunt from element [4 so that the circuits are in their normal condition as previously described.

Thus the operator may change a route only after a predetermined time in the face of an oncoming train, which allows the train sufiicient time to either stop before it reaches the track switch or to enter the detector track section and thereby prevent'the operation of the switch machine.

Electric lock equivaZent.-The electric lock equivalent feature is effective in the event that the operator actuates lever SML to a new position while the track switch is locked as, indicated by relay L being deenergized. -With the circuits in the conditions indicated, it will be assumed that relay L is dropped to lock track switch TS and that the operator actuates lever SML to its dotted line position before relay L is picked up. This has no effect on relayLP (which is deenergized by the dropping of relay L) nor relay WZ when relay L is again picked up because the circuit from (B) through contact 9 in its dotted line position is open at front contact 25 of relay LP and since contact 28 of relay LP was left in its right-hand position the circuit is likewise open at this point. i

It is therefore necessary for the operator to restore lever SML to its full line position which closes a circuit from (B+) contact ll] of. lever SML, contact 23 of relay LP in its right-hand Closed contact l9 4 position, winding of relay LP, over' line conductor 6 and through the winding of relay WZ to the mid-tap of the control oifice battery. This picks up the neutral contacts of relay LP, after which lever SML may be actuated to its dotted line position for closing a circuit from (B) through contact 9 of lever SML, front contact 25 of relay LP and over the previously described circuit for controlling relay WZ.

For the reverse condition, relay LP will have its neutral contacts positioned to the left with lever SML in its dotted line position. Then when the switch is locked the dropping of relay L deenergizes relay LP for dropping its neutral contacts. If lever SML is then moved to its full line position, relay LP cannot be picked up as long as front contact 24 of relay L is open. It cannot be picked up when this contact again closes, from (3+) through contact 10 of lever SML, because polar contact 23 of relay LP is in its dotted line position and neutral contact 22 is dropped. By restoring lever SML to its dotted line position for picking up relay LP (after the switch is unlocked) over a circuit extending from (B), contact 9 of lever SML in its dotted position and contact 28 of relay LP in its left-hand dotted position, then lever SML will be effective to energize the control line circuit from (3+),

contact Ill of lever SML'and front contact 22 of relay LP over the previously described circuit.

It will thus be observed that relayxLP is an indicating means for indicating (by means of back contact 26) the locked and unlocked. condition of the remote track switch. Furthermore, this LP relay registers (by means of its contacts 23 and 28) the particular control which is effectively applied to the control line circuit by the lever. These contacts maintain the circuit to the control line opened when relay LP has dropped its neutral contacts in response to a locked condition of the switch control means, whenever the control lever is out of correspondence with contact 23 or 28 of this relay.

It is to be understood that the principles of the invention may be applied to various othertypes of systems and that various types of track layout may be controlled in a similar manner without departing from the spirit of the present invention, the track layout of the present disclosure being chosen merely for providing a simplified showing which could be clearly described in the specification.

Having described a traffic controlling system as one specific embodiment of the present invention it is desired to be understood that this form is selected to facilitate in the disclosure rather than to limit the number of forms which it may assume and it is to be further understood. that various modifications, adaptations and alterations may be applied to the specific form shown in order to meet the requirements of practice without in any manner departing from the spirit or scope of the present invention except as limited by the appended. claims.

Having described my invention what I claim 1. In a centralized traflic controlling system for railroads, a track section, a track switch associated with said section, a control lever, a control circuit distinctively energized in accordance with the position of said lever, switch control means responsive to the actuation of said lever for controlling the'operation of said track switch, locking means responsive to specific conditions of said section for locking and unlocking said switch control means, a polar neutral relay included in said control circuit, and means including contacts of said polar neutral relay and contacts of said control lever for preventing operation of said switch control means subsequent to the restoration of said locking means to an unlocked condition if said control lever has been moved to a different position while said locking means was effective.

2. In a system for the remote control of power operated switches, a control circuit over which a power operated switch machine is controlled, a switch control relay and a neutral polar lock repeater relay connected in series in said control circuit, a lock relay, a control lever, means responsive to the actuation of said lever for actu ating said switch control relay and said lock re peater relay to corresponding positions in accordance with the distinctive energization of said control circuit, means controlled by said lock relay for preventing the actuation of said switch control relay, andmeans including cooperating contacts of said lock repeater relay and contacts of said lever for rendering said lever ineffective to control the energization of said control circuit if said lever should be moved to a different position while said lock relay is effective to prevent the actuation of said switch control relay.

3. In a system for remote/control of power operated track switches, a manually operable lever at a control point, a control circuit extending from the control point to .a distant track switch, switch control means adjacent the switch and responsive to the polarity of energization of said control circuit for governing operation of said switch to a normal or a reverse position,

locking means for at times opening said control initial energization thereof tomaintain the con-.

tinuity of the control circuit independently of such correspondence and thereby permit 'a change in the energization of said control circuit by a subsequent movement of said lever.

45111 a system for remote control of power operated track switches, a manually operable lever at a control point, a control circuit extending from the control'point to a distant track switch, switch control means adjacent the switch and responsive to the polarity of energization of said control circuit for governing operationof. said switch to a normal or'a reverse position, locking means for at times opening said control circuit to prevent operation of said switchcontrol means under trafiic conditions adverse to suchoperation, a neutral polar relay 'at said control point included in said control circuit, contact means operated by 'the neutral'armature.

of said neutral polar relay for opening said control circuit, and circuit means including polar contacts of the neutral polar relay and contacts of the lever in corresponding positions for providing a shunt for said'contact means, whereby operation of the switch control means is prevented if said lever is moved to a diiTerent position while said locking means is effective to open said control circuit but is permitted if said lever is moved to a difierent position while said locking means is ineffective.

5. In a system for remote control of power operated track switches, a manually operable lever at a control point, a control circuit extending from the control point to a distant track switch, switch control means adjacent the switch and responsive to the polarity of energization of said control circuit for governing operation of said switch to a normal or a reverse position, locking means for at times opening said control circuit to prevent operation of said switch control means under trafiic conditions adverse to such operation, a retained-neutral-polar relay at said control point included in said control circuit and responsive to current flow therein so as to pick up its neutral contacts when energized and drop them when deenergized with its polar contacts operating to positions dependent upon the polarity of such energization, said retainedneutral-polar relay being so constructed as to maintain its neutral contacts picked up upon a relatively quick reversal of the polarity of its energization, contact means operated by the neutral armature of said retained-neutral-polar relay for opening said control circuit, and circuit means including polar contacts of the retained- 10 neutral-polar relay and contacts of the lever in corresponding positions for providing a shunt for said contact means, whereby operation of the switch control means is prevented if said lever is moved to a different position while said lock- 1 ing means is effective to open said control circuit but is permitted if said lever is moved to a different position while said locking means is ineffective.

SEDGWICK N. WIGHT. 2O

DISCLAIMER 2,132,139.Sedgwiclc N. Wight, Rochester, N. Y. RAILWAY TRAFFIC CONTROLLING SYSTEM. Patent dated October 4, 1938. Disclaimer filed May 18, 1939, by

the assignee, General Railway Signal Company.

Hereby enters this disclaimer by disclaiming from claim 1 any system of centralized trafiic control, except wherein the switch control means comprises a polar relay included in series with the polar neutral relay in the control circuit specified;

[Ofiicial Gazette June 6, 1 939.]

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