US1581608A - Electrically-operated track switch - Google Patents

Description

April 20,1926. 1,581,608

S. S. STOLP ELECTRICALLY OPERATED TRACK SWITCH Filed Dec. 12 1925 2 Sheets-Sheet 1 I 9.1mm, 64/72/51. 5. 6701,]?

April 20 ,'192e.- i 1,581,608

, s. s. STOLP I BLECTRICALLY OPERATED TRACK SWITCH Filegl Dec. 12. 1923 2 Sheets-Sheet 2 LS/ /EL 6701.1?

Patented Apr. 20, 19245.

UNITED STATES PATENT OFFICE.

SAMUEL S, STOLI, OF MANSFIELD, OHIO, ASSIGNOR TO THE OHIO BRASS COMPANY,

OF MANSFIELD, OHIO, A CORPORATION OF NEW JERSEY.

ELECTRICALLY-OPERATED TRACK SWITCH.

Application filed December 12, 1923.. Serial No. 680,150.

To all whom it may concern:

Be it known that I, SAMUEL S. S'roLr, a citizen of the United States of America, residing at Mansfield, in the county of Richland and State of Ohio, have invented certain new and useful Improvements in an ElectricallyOperated Track Switch, 01": which the following is a specification.

My invention relates to electrical systems and more particularly to that class of systems for the automatic operation of track switches.

The object of my invention is to produce a system in which the track switch can be controlled by the operator on an electrically operated car whereby he may throw the switch to either straight ahead or to a curve position at will by operating the controller in such a manner as to supply.

current to the motors operating the car or to deprive them of current. It is the further object of this inventionthat while operating as above that the current which open ates the system will be continued to the sys tem for a predetermined length of time in order to assure the track switch being thrown in the proper direction; to prevent. the burning out of certain coils, later described, by means of which the switch tongue is moved providing the car should stand in cooperative relation with the system beyond the aforesaid predetermined time; and to prevent a movement of the switch tongue in the wrong direction after having been initially moved to the proper direction.

In the drawings accompanying this specitication Fig. l is a diagrammatic view showing the principle upon which is based the system of operation by a moving vehicle.

Fig. 2 is a diagrammatic View of the system as such embodying my invention with the various operating parts in normal position as when the system is not being employed to operate the track switch. It will be understood that the switch tongue in the normal position may be thrown either to the straight ahead or curve position.

Fig. 3 is a diagrammatic view showing the arrangement of the various parts and ter the system has been engaged by the cur rent collector for a predeterminedtime with power off the motors.

Fig. 5 is a diagrammatic view showing the relation of the variousparts and cir-' cuits .when the system is engaged by the current collector with power on the mo tors.

Referring to Fig. 1 the electric cars are usually equipped with a current collector IV supported on the car by means of a trolley pole T and from which circuits lead to various apparatus mounted upon the car. These may comprise heaters H, lights L, air compressors F, driving motors M and controller C by means of which current is applied to or cut off from the motors M, all circuits leading to the ground. Current is liable to flow through the heaters, lights and air compressors irrespective of whether the controller C is on or oft, and as the current through these apparatus, which I will term the auxiliary current, is liable to be or" considerable amount as compared with the cur rcnt'which may flow through the motors M, consideration must be given to this auxiliary current in the design of the parts or arrangement of .my system and which will be explained hereinafter.

The system is so arranged that if the operator desires to go in a certain direction he turns his controller to the on position, which I will hereinafter term the power on position, and if he desires to go in the opposite direction at a switching point he will turn his controller to the off position, which I will term the power off position. I have shown the system so arranged that if the operator desires to go straight ahead he will turn his controller to the power off position and if he wishes to take the curve he will turn hiscontrollei to the power on position.

Referring now to Fig. 2, I will explaii the same which embodies a preferred arrangement of my system. Positioned adjacent the trolley conductor 1 is a pan P provided with two parallel and normally insulated contact members 2 and 3 which are adapted to be engaged by the current collector WV on a passing vehicle and under which circumstances the members 2 and 3 are then electrically connected. The relative arrangement of the trolley conductor and contact members is such that when the current collector engages the pan P the wheel will be out of engagement with the conductor 1 and remain out of engagement until the collector passes off the pan P. The electrically operated track switch S comprises a switch tongue i, and two operating solenoids 5 and. 6 and a plunger 7 connected to the tongue 4. When the solenoid 5 is energized the plunger 7 is drawn inwardly and the tongue 4; moved to the straight ahead position as shown in Fig. 3, and when the solenoid 6 is energized the plunger 7 is moved outwardly and the tongue is moved to the curve position as shown in Fig. 2. Each solenoid has a terminal connection designated as 8 and 9 respectively, and which have a common ground connection 10. i

I employ also an electrically operated switch A having a winding 11 upon its core and a switch arm 12 which operates between the contacts 13 and l t but which is normally in engagement with the contact 13. The coil 11 which is of comparatively few turns and heavy wire has its terminals connected to the trolley wire 1 by the conductor 15 and to the contact member 3 by the conductors 16 and 17 respectively. This permanently connects the members 1 and 3 together at all times and supplies current thereby to the system when the contact members 2 and 3 are engaged by the collector and also supplies current to the motors M if the vehicle passes the pan P with power on. It the current collector engages the contacts 2 and 3 with power on a heavy flow of current will pass from the trolley wire 1 to the contact 3 through the coil 11 and then through the car motor circuit to ground, and this current will be sufficient so that the core of the switch A will pick up the switch arm 12 into engagement with the contact l l. If, however, the engagement is made with power OK the current flowing through the coil 11 will not be suflicient to cause the switch arm 12 to be moved. In designing the switch A account must be made of the auxiliary car currents as they must also pass through the coil 11 and will add to that which passes through the motors. The auxiliary currents may at times be quite large and, therefore, the coil 11 must be designed with this in mind and so that the ampere turns of the coil 11 based on the auxiliary current, will not be sufficient to pick up the arm 12 when the collector engages the pan P with power oil.

I also employ an electrically operated switch B provided with a coil 18, a switch arm 19 and contacts 20 and 21. This switch is norm-ally in an opened position. The coil 18 has one terminal connected to the contact member 2 by the conductor 22 and the other terminal has a ground connection 23. I have shown the gi'oundconnection leading directly to the ground, but it may be led to any other conductor in the system which will give it a ground without interfering with the operation of the switch B as hereinafter described. The switch arm 19 is connected to the trolley wire 1 by means of the conductors 24 and 25 or the conductor 25 may be connected to the conductor 15. The current flowing through the conductor 25 may amount to six to ten amperes depending upon the resistance of the solenoids 5 and 6. The resistance of the coil 18 may be quite high so as to reduce the current flowing therethrough to a small value. Whenever the contact members 2 and 3 are bridged by the collector W either with power on or power off the coil 18 is energized thereby picking up the switch arm 19 which then engages with the contacts 20 and 21. The contact 20 is connected to the switch arm 12 by means of the conductors 26 and 27. The arm 19 will be held in engagement with the contact 20 as long as the collector is in engagement with the pan P.

As I desire to maintain the switch B in a closed position for a predetermined time and as the current collector may engage and leave the pan P before the predetermined time has elapsed, I provide the switch B with a time factor so that the arm will not drop as soon as the collector leaves the pan. This may be done in various well known ways, as for instance, by means of a copper sleeve 28'as shown, or surrounding the coil 18 or by making the arm 19 of a magnetic material and having it engage the core of the coil 18 thereby depending upon residual magnetism to hold the switch up for a predetermined time after the collector leaves the pan, or a combination of these means, or I may employ other well known means. It is desirable to maintain the switch B closed for a full predetermined time, as the current which energizes the coils 5' and 6 is controlled by this switch which is normally open and sufficient time for the flow of current through the solenoids 5 and 6 must be given to properly saturate these solenoids in order to positively move the tongue 4.. Leading from the contacts 13 and let are circuits leading to the solenoids 5 and 6 respectively. In the circuit leading to the coil 5 I insert an electrically operatedswitchC for controlling this circuit andwhich 1s normally closed. The object of this switch is to open the circuitto the solenoids 5 if the current collector engages the pan P for too long a time. I prefer to design the solenoids 5 and 6 with as high a degree of efficiency as possible and this will mean that if current is supplied to them for too long a time they are liable to burn out. I insert the switch C in the circuit leading to the solenoid 5 as it is this solenoid which is liable to be effected if the collector engages the pan P for too long aftime, as this is liable to happen when the collector coasts with the power off position and then stops with the collector in contact with the pan. It is quite unusual for the collector to engage the pan with power on and then stop on the pan and, therefore, I protect the solenoid 5 with the switch G.

The circuit leading from the contact 13 to the solenoid 5 comprises the conductor 29, switch arm 30, and conductor 31. The switch C comprises two duplicate coils 32 and 33 connected up for, differential operation. One terminal of each coil is connected to the switch arm 30 by the conductor 34. The other end of the coil 32 is connected to the conductor 26 by means of the conductor 35 and the other end of the coil 33 is connected to the conductor 25 by means of the conductor 36. The operation of the switch C consists in normally energizing the coil 33sas this coil is connected at all times to the source of power through the conductors 25 and 36 and to the ground through the conductors 34, 31, solenoid 5 and conductors 8 and 10 and this maintains the switch 30 closed with the contact 37 under normal conditions. The coil 32 is energized only when the switch B is closed. As soon as the switch B is closed the switch arm 30 is then connected directly with the source of power and is of substantially the same potential as the source of power, therefore, there is no difference of potential between the source of power and the switch arm 30, and as the terminals of the coils 32 and 33 are connected to the source ofpower and the switch arm 30 there will be no flow of current through either coil 32 or 33 when the arm 19 is closed. Therefore, there will be no energizing current in the coils 32 and 33 and as soon as the residual magnetism in the core of the switch C has been sufliciently reduced the arm 30 will drop. As soon as the arm 30 drops it is then disconnected from the source of power andthere is then a full difference of potential between the source of power and switch arm 30 and current will flow through both coils 32 anc 33 in opposite directions and maintain the switch C open as long as the switch B is closed. In other words, the switch C is opened after a predetermined time after the closing of the arm 19 by the short circuitingof the coils 32'and 33 and is maintained open by differential action of the coils 32 and 33 as long as the arm 19 remains closed, but as soon as the arm 19 opens the coil 32 is de-energized and the arm 30 raised through the continued energization of the coil 33.

The contact 14 is connected to the solenoid in some manner should become stalled with the contact in engagement with the pan P, current would continue to flow through the solenoid 6 as long as the collector engaged the pan P, but this is a veryremote condition of operation and might be termed an accidental operation and can be taken care of by designing the solenoid 6 so as to withstand a flow of current for a greater length of time than the solenoid 5. The solenoid 40 can be eliminated in which case current will be supplied to the solenoid 6 only for such time as the collector is in engagement with the pan P with power on. a

The resistance of the coils 32 and 33 is made veryhigh, possibly 10,000 ohms, or: more each, so that the current flowing therethrough and into the circuit 31 will not. be

sufficient to interfere with the operation of the solenoid 5. g I i The operation ofmydevice is as follows: If the car operator desires to move straight ahead when he approaches a switching point, he will throw his controller to power off and. coast past the pan P which is located shortly in advance of the switch tongue 4. The moment the collector V engages the pan P .current will flow from the trolley conductor 1 through the parts 15, 11, 1c, 17, .3, W, 2, 22, 18 and 2a. This will energize the coil 18 and close the switch arm 19 with the contact 20. Ourrent will then immediately flow from the trolley wire 1 through the parts 25,. 24, 19, 20, 26, 27, 12, 1s, 29, a7, 30, 31, 5, s and 10 and the solenoid 5 will be energized thereby moving the switch tongue 4 to the straight ahead position and the various parts will assume the condition shown in Fig. 3. As soon as the arm 19 closes the coil 32 is connected in the circuit as described and the switch C will operate-to drop the switch arm 30 aftera predetermined time thereby cutting ofi current through the solenoid 5. The condition of the parts will be as shown in Fig. 4:.

As soon as the collector has left the pan P the coil 18 will be deenergized and after a lapse of time the arm 19 will open and the arm 30 immediately closed thereafter thereby placing the parts in a normal position as shown in Fig. 4.

If the operator in coasting past the pan P with power oli should stop with the collector on the pan, the switch arm 19 will remain closed as long asthe contactor engages the pan and the switch arm 30 will remain open for this period thereby protecting the solenoid 5 from burning out. In order to move ahead, however, it will be necessary for the operator to turn his controllerto power on and this will then tend to throw a heavy current through the solenoid 11, as previously explained, and this would cause the arm 12 to be raised and the currentwould then flow through the solenoid 6 and set the switch in the wrong direction. Therefore, in order to prevent a false operation, I connect the contact 21 with the coil11 through the medium or the conductors 41 and 16. This places a substantial shunt across the coil 11 so that the current which would pasjs'through the car circuits will be divided between the circuits 15, 11, 16, 17, 25, 24, 19, 21, 11. This will prevent suflicient flow or current through the coil 11 to operate the arm 12 into engagement with the contact 14.

If the operator desires to take the curve he will pass the pan P with power on in which case the heavy current flowing through the coil 11 will cause the arm 12 torbe pickedvup and simultaneously the switch 20 will be closed and currentwill.

flow through the coil 10 and solenoid 6 thereby energizing the switch A to hold the arm 12 in a raised position, and energizing the solenoid 6 to move the track switch to the curve position and the parts will assume the position shown in Fig. 5. As soon as the collector has passed over the pan P the coil 18 is deenergize d, the arm 19 will drop after a predetermined time, the coil 40 will be de energized likewise the solenoid 6 and the arm 12 will drop. During this cycle of operation the arm 30 will likewise drop as the time factor of the switch B is preferably greater than that of the switch C thereby eliminating arcing at the contact 20.

If the coil 40 is not used and the circuit 88 connected to the circuit 39 and a time factor of dropping the arm 12 'is incor porated in the switch A, which is somewhat greater than the time factor for the opening of the switch 0, then the danger of the arm 12 dropping and closing the circuit to the solenoid 5 before the arm 19Ydrops would be avoided, because the switch C would open prior and protect the solenoid 5 from being energized and throwing the switch in the wrong direction.

There will, of course, be many modifications which will suggest themselves to those skilled in the art which will still be within the scope'of my invention and I do not wish to be limited otherwise than by my claims.

, circuits to energize the track switch operating means to move the track switch in one direction or the other, electrical operating means connected to one or the contact members and to the trolley conductor to control said switch, a switch in the power circuit to' normally maintain the circuit open, electrically controlled operating means to close the switch and having a connection to the other contact member, means to delay the opening of the last said switch after closing, an electrically operated switch in one of the branch circuits to normally close the circuit and to open after a predetermined time after the closing of the normally open switch and ground connections for the system.

2. A switch operating system comprising, a trolley pan having two contact members to be electrically connected by a current collector, a' trolley conductor, a track switch,

electrical operating means therefor, a power circuit leading from the trolley conductor to the track switch operating means to operate the switch in either of two directions, an electrically operated switch connected to the pan for operation to control the direction of operation of the track switch, a normally open electrically operated switch electrically connected to the pan for controlling the power circuit and having means to delay the opening of the switch after closing, and a normally closed electrically operated switch in the power circuit to control said circuit and operating to open the circuit after a predetermined time after the normally open switch has closed the same, the normally closed switch having a time factor not to exceed that of the normally open switch.

3. A switch operating system comprisin a trolley pan having two contact members to be electrically connected by a current collector, a trolley conductor, a track switch,

electrical operating means therefor, a power trically connected to the pan for controlling the power circuit and having means to delay the opening of the switch'at'ter closing, and a normally closed electrically operated switch in the power circuit to control said circuit and operating to open the circuit after a predetermined time after the normally open switch has closed the same.

4. A switch operating system comprising in combination, a trolley pan having two contact members to be engaged by a current collector, a track switch and electrically con trolled operating means therefor, a power circuit to supply current to the track switch operating means and having branch circuits leading to the operating means, a selector switch automatically connecting the power circuit to one or the other of the branch circuits to energize the track switch operating means to move the track switch in one direction or the other, electrically controlled operating means .to control the said switch, a normally open switch in the power circuit, electrically controlled means to close the normally open switch when and to remain closed while and regardless of the time the pan is engaged by a collector, and means to delay the opening of the normally open switch after the collector leaves the pan.

5. A switch operating system comprising in combination, a trolley pan having two contact members to be engaged by a current collector, a track switch and electrically controlled operating means therefor, a. branched power circuit to supply current to the track switch operating means and leading to the operating means, a selector switch automatically connecting the power circuit to one or the other of the branch circuits to energize the track switch operating means to move the track switch in one direction or. the other, electrically controlled operating means to control the said switch and a normally open switch in the power circuit, an operating coil to close the normally open switch when and to remain closed while and regardless of the timethe pan is engaged by a collector and having its terminals connected to a pan contact and to the ground.

6. In a switch operating system the com bination of a contact pan to be engaged by a current collector, atrolley conductor, an electrically operated track switch, a power circuit leading to the track switch, an electrically operated selector switch for controlling the direction of operation of the track switch, a normally open switch controlling the power circuit, means to close the normally open switch when the collector engages the pan and maintain the switch closed regardless of the time the collector engages the pan and a normally closed and electrically operated switch to open the power circuit at another point after a predetermined time afterthe collector engages the pan.

7. The combination with a track switch operating system adapted to work power on and power oil the system to move the gardless of the length of time current is supplied to the system and to open after a predetermined time after the collector disengages the contacts and the system is deprived of current.

8. In a switch operating system the combination, of a contact pan having'two con tact members, a trolley conductor,a track switch, electrical means to operate the switch in either of two directions, a normally open power circuit having an electrical connection with the trolley conductor and having branch circuits connected to the switch op erating means, a switch to control the connection of the power circuit to the branch circuits to operate the track switch in difterent directions and having electrical operating means connected to one contact memher and the trolley conductor, a switch for closing the normally open power circuit when the contact members are engaged by a current collector, electrically operated means to close the last said switch connected to the other contact member and having a ground connection, and an electrically operated switch normally closing one of the branch circuits and having a pair of coopcrating coils to controlthe said switch and so connected to the system as to open after a predetermined time after the closing of the previous circuit and remain open as long as the normally open power circuit switch is closed and to close whenthe said switch is opened.

' 9. In a switch operating system the combination, of a pair of contact members to be connected by a current collector, a trolley conductor, an electrically operated track switch, a normally open power circuit having branch circuits connected to the track switch, a circuit controlling switch connecting the power circuit to the branch circuits to operate the track switch in either of two directions when the contact members are engaged by the current collector with either power on or power off, an electrically operated switch to close the normally open power circuit when the contact members are engaged by the current collector and to maintain the switch closed while the contact members are engaged regardless of the length of engagement, and electrically operated means to open one ofthe branch circuits after a predetermlned time if the coling branch circuits connected to the track switch, a circuit controlling switch connecting the power circuit to the branch circuits to operate the track switch in either of two directions when the contact members are engaged by the current collector with either power on or power off, an electrically operated switch to close the normally open power circuit when the contact members are engaged by the current collector and tomaintain the switch closed while the contact members are engaged regardless of the length of engagement, and electrically operated means to open one of the branch circuits after a predetermined time if the collector engages the contact members too long and to close after the opening of the switch controlling the normally open power circuit.

11. In a switch operating system the combination, of a trolley conductor, a trolley pan to be engaged by a current collector, an

electrically operated track switch, circuits leading to the track switch, a normally open power circuit, a switch controlling the connection of the power circuit to the first said circuits to operate the switch in the desired direction when the collector engages the pan with power on or .power oil, a switch to close the normally open power circuit and maintain it. closed regardless of the length of time the collector engages the pan and provided with means to maintain the switch closed a predetermined time after the collector leaves the pan and a switch normally closing one of the circuits to the track switch and provided with means to open the switch .a predetermined time after the normally open switch is closed irrespective of whether the collector is in engagement with the pan or not. 7

12. In a switch operating system the combination, of a trolley conductor, a pan having a pair of contact members to be connected by a current collector, an electrically operated track switch, a branched power circuit supplying power from the trolley conductor to the track switch, an electrically operated switch controlling the branched power circuit to operate the track switch in the desired direction when the contact members are engaged by the current collector with .power on or power oil, the operating means for said controlling switch comprising a coil connected to the trolley conductor and to one of the contact members,

an electrically operated normally open switch controlling the power circuit, the operating means for said switch having a connection to the other contact member and a ground connection to close the switch while the collector engages the contact members, and a circuit to be closed from the first mentioned contact member to the trolley conductor by the normally open switch when the switch closes the power circuit and means to open one of the branch circuits when the normally open switch has been closed for a predetermined time.

13. In a switch operating system the combination, of a trolley conductor, a pan having a pair of contact members to be electrically connected by a current collector, an electrically operated track switch, a normally open branched power circuit supplying power to the track switch to operate it cesired when the collector engages the contact members with ,power on or power oli', an electrically operated switch to control the branched power circuit, an electrically operated normally open switch to close the power circuit and connectone of the contact members to the trolley conductor when the collector engages the contact members, and means to control the opening of one of the branch circuit-s after the normally open switch has closed.

14. In a switch operating system the combination, of an electrically operated t'ack switch, a trolley p an, a trolley conductor, a normally open branched power circuit connected to the track switch to energize the same, a selector switch interposed in the power circuit to con-trol the direction of operation of the track switch when the pan is engaged by a current collector, operating means for said selector switch connected to the trolley conductor and the pan and a switch to close the normally open power circuit and place a shunt about the said operating means when the pan is engaged by the current collector and to maintain the power circuit closed and the said shunt regardless of the length of time the collector engages the pan to prevent the selector switch being operated and change the position of the track switch.

15. In a switch operating system the combination, of a contact pan to be engaged by a current collector, a trolley conductor, an electrically operated track switch, a power circuit leading to the track switch, an electrically operated selector switch for conclosed regardless of thetime the collector engages the pan, the normally open switch operating to also prevent operation of the selector switch while the normally open switch is closed.

bination, of a trolley conductor, a pan to be engaged by a current collector, an electrically operated track switch, a normally open branched power circuit for energizing the track switch and move it to either of its positions when the collector engages the pan with power off or power on, an electrically operated selector switch to control the branched power circuit, an electrically operated normally open switch to close the power circuit and maintain it closed while the collector engages the pan and regardless of the length of time engaged, and means to shunt the selector switch while the normally open switch remains closed.

17. A switch operating system comprising in combination, an electrically operated track switch arranged to be controlled by a moving vehicle with power on and power off the motors, electrically operated means to control the directional operation of the track switch and means to deprive the electrically operated means of current after it has operated the electrically operated means with power on.

18. A switch operating system comprising in combination, an electrically operated track switch arranged to be controlled by a moving vehicle with power on or power off the motors, a power circuit with branches leading to the track switch, electrically operated means to control the current in the branch circuits and the directional operation of the track switch, a coil to operate the said means and means to deprive said coil of current after the system has worked power on.

19. A switch operating system controlled by the movement of a car comprising in combination, an electrically operated track switch, a branched operating circuit, a controlling switch therefor having an operating and a holding coil, and means to de-energize the operating coil after it has functioned to operate the controlling switch and maintain it de-energized while the car is cooperating with the system.

20. A switch operating system comprising in combination, an electrically operated track switch, a branched operating circuit, a controlling switch therefor to position the branch circuits relative to the operating circuit and having an operating coil and means to deenergize the coil after it has functioned to operate the controlling switch.

21. A switch operating system comprising in combination, an electrically operated track switch, a branched operating circuit, a controlling switch therefor to position the branch circuits relative to the perating circuit and having an operating coil and means to prevent the energizing of the coil.

'22. A switch operating system'comprising in combination, an electrically operated 16. In a switch operating system the comtrack switch, abra-nched operating circuit, acontrolling switch therefor to position said branch circuits having an operating coil and electrically operated means to energizing of the coil.

23. Aswitch operating system comprising in combination, an electrically operated track switch, a branched operating circuit, a controlling switch therefor having an operating coil to position the switch relative to the branch circuits and electrically operated means controlled by a moving car to prevent the energizing of the coil.

24:. A switch operating system comprising an electrically operated track switch, a branched operating circuit therefor, a controlling switch for positioning said branched circuits and having an operating coil and connections to said coil and electrically controllled means to control the circuit to'said CO1 25. A switch operating system comprising in combination, an electrically operated track switch arranged to be operated by a moving vehicle with power on or power off the motors, electrically operated means to control the directional operation of the track switch, means to prevent the flow of current to the electrically operated means to operate the same after the track switch has been positioned and means to prevent the flow of current to the track switch after a predetermined time.

26. A switch operating system comprising in combination, an electrically operated track switch arranged to be operated by a moving vehicle with power on or power oi the motors, electrically operated means to control the directional operation of the track switch and means to prevent a current flowing to the electrically operated means to operate the same after the track switch has been operated with power off.

27. A switch operating system comprisin in combination, an electrically operate track switch, a branched operating circuit, an electrically operated switch to position said branch circuits, means to position said electrically operated switch comprising a coil and operating circuit therefor to operate said electrically operated switch with power on the motors and means to prevent current flowing through the coil after the track switch has been operated with power off the motors.

28. In an electrical switch operating system, the combination of a divided track switch operating circuit, a selector switch therefor having an operating coil, a switch for controlling one of the branches of the track switch operating circuit, electrically operated means to normally maintain the control switch in the branch circuit closed prevent the and Op n -l 1 e ntlTQl$W Qh i he br circuit after a. predetermined lapse of time.

29- n a syst m for oper t n a sw tc m a t olley W re with --P W 0,1 and powe 11' a erei des i ed. he ommation with a gelector switch therefor and its operating coil of a control switch electrically erated y the wr enfi f om-th l ey and leads from the control switch direct to the opposite terminals of the operating coil and 10 forming a normally open circuit and arranged to be closed by the control switch to render the selector switch inoperative.

In testimony whereof I aflix my signature.

SAMUEL S. STOLP.

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