US1205463A - Railway-train-control system. - Google Patents

Description

J. C. McDONALD.

RAILWAY TRAIN CONTROL SYSTEM.

APPLICATION 111150 JAN. 18. 1916.

1,205,463. Pa1ented Nov. 21, 1916.

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' $513 4&4 fiim .wtvlaext com: o. menonann," on NEW YORK, N. Y.

RAILWAY-TRAIN-CONTROL SYSTEM.

Specification of Letters Patent.

Application m January 1a, 1916. Serial No. 72,863.

To all whom it may concern Be it known that I, JOHN G. MCDONALD, a citizen of the United States of America, and a resident of New York, in the county of New York and State of New York, have invented certain new and useful Improve- .ments in Railway-Train-Control Systems, of

which the following is a specification.

My invention relates to improvements in railway train control systems and particularly to combined train-stopping and speedcontrol systems, and embodies improvements over the system of the same general nature set forth in my a plication for Letters Patent Serial No. 4 ,581, filed August 27, 1915. As in my said prior application, I have illustrated my invention particularly as applied to electric roads wherein the trains are operated by electric motors d'eriving current from a third rail or other conductor other than the track rails; but it will be apparent that the system isv equally applicable to roads whereon the trains are operated by steam or other motive power other than electricity. In the following description I will generally refer to the 1 conductor from which the trains receive current for motive power, as the thlrd rall,

- and will generally refer to the conductor from which the trains receive current for control, as the fourth rail but it will be understood that anyother conductors, for

example, over-head trolley wires, may be substituted for what are, strictly speaking, third and fourth rails, without departure from my invention.

My invention comprises controlling circuits and instruments, the latter being, generally, of the nature of relays, and I have illustrated the track relay of each block as controlled by track circuits; though other well known means for the control of such to provide simple and effective means for positively stopping trains; to prevent entry of trains into blocks which are already occupied; to maintain proper block intervals between trains with provision permitting,

under exceptional circumstances, (such forexample as the stalling of a train ahead) the passage of a train into a block already occupied; to make the system readily a plicable to'existing railways; and general y to make thecircuitsv and apparatus of the system simple and reliable, and to cause such circuits and apparatus to afford ample pro tection.

I will now proceed to describe my invention with reference to the accompanying drawings, and will then point out the novel features in claims.

In the drawings: Figure 1 is a diagrammatic view showing circuits and instruments for one track of a double track railway, the dlrection of normal progress along such track being indicated byan arrow. Fig. 2 1s a diagram of train circuits which may be employed in connection with circuits shown in Fig. 1. Fig. 3 is a view showing Patented Nov. 21, 1916. 1

more or less diagrammatically a relative arrangement of the power circuit conductor or third rail and the signal circuit conductor or fourth rail with the double contacts of the train shoe and associated parts, the third rail, the fourth rail, and the insulation support for the third rail being shown in vertical section.

In the embodiment of my invention herein lllustrated and described, at least one of the two parallel rails of each track is insulated from the ground and divided into block sections, such sections being insulated from each other. The length of such track sectionsv will depend upon traffic conditions and may be determined readily bythose skilled in the art. The third rail or propulsion current conductor may be continuous; but the fourth rail or traincontrol circuit conductor is divided into block sections, preferably corresponding generally to'the division of the track rail into block sections as above described, the sections of the fourth rail being not nee essarily, however, absolutely cotermzinus with the corresponding sections of the track rail.

Referring now to Fig. 1: R and R designate track rails of which R is shown divided into block sections 2, 3, 4, etc. For each'such block therev is a corresponding track relay TR, TR, etc. I have not illustrated a track relay for block 2, but it will be understood that the same instruments and circuits are provided for each block. For each block there is also another relay, commonly termed a line relay, and designated by ref erence characters L L etc. (It will be understood that the term relay is em ployed herein in a generic sense, as inclusive of any type of electrically controlled switching means). I have illustrated the track relays TR and TR, etc., as controlled by track circuits 7 in the ordinary manner, each of which circuits will be shunted by the wheels and axles of a train present on the corresponding block, so as to deenergize the corresponding track relays TR TR*, etc. T designates the third rail or propulsioncurrent conductor and T designates the fourth rail or train control conductor. 0 designates a common return conductor for the train control circuits and S S etc., designate transformers, one for each block section, sgpplying alternating current for the train control circuits. SX designates the conductor supplying the alternating current to the primary coils of these transformers.

The line relays L L etc., are time element or delay action relays; that is to say, a predetermined interval of time is required for the closing of contact by these relays following the energization of their magnets. Such delay action relays are well known, and I do not limit myself to the use of any particular type of such relay; but as a diagrammatic illustration of the delay action character of these relays I have shown the armature of each such relay as provided with a controlling dash-pot D. It is well known that by means of such a dash-pot employing either liquid or air as the impeding medium, the time required for the closing of contact by the relay may be anything desired within reasonable limits. Each of the relays TR TR, etc., has three independent armature contact points a, b, and c, with corresponding fixed contact points.

The circuits will be best understood by describing the operation of the system. Suppose a train to enter block 3 from block 2. As soon as the wheels of that train enter block 3, the track circuit controlling relay TR will be shunted, deenergizing the magnet of relay TR and permitting its armature contacts to drop back. Upon the deenergization of relay TR a circuit will be completed from point 8 of common return conductor 0 through armature contact a of relay TR and the back contact of that armature through conductor -D* and the magnet of line relay L and thence, through conductor C to the c armature of a track relay of a block ahead (in this case the track relay TB of the second block ahead) and (this block 6 being understood to be clear) through the c armature contact of relay TR, and the corresponding; front contact stop, and the armature contact d of the corresponding relay L and the corresponding rear contact, through the secondary winding 8 of the transformer S to return conductor 0 and thence back to starting point 8. By the completion of this alternating current circuit the relay L will be energized (it will be understood that these relays L L etc, are alternating current relays as well as delay action relays) and therefore the armature of relay L will be attracted; but since this relay L is a delay action relay, a predetermined interval of time will elapse following the energization of the magnet of this relay L, before contact is made with the front contact of that relay L Should the train so entering block 3 proceed through that block at a speed greater than that for which delay action relay L has been timed, such train will reach the entrance of block L before'the front contact of relay L has been made; in which case (since the front contact of this relay L controls the supply of alternating current from secondary s of transformer S to section T of the fourth raiL) there will be no alternating current on fourth rail section T, and, therefore, by means hereinafter described the train will be brought to rest at the entrance of block 4. If, however, the train in block 3 proceeds through that block ata speed not greater than that for which relay L has been set,

,by the time that train has reached the entrance of block 4 relay L will have closed its front contact, and thereby alternating current from secondary coil 8 of the transformer S will be supplied through the front contact of that relay L to the fourth rail section T, thereby permitting the train to proceed, as hereinafter described with reference to the circuits and instruments carried by the train. But now suppose that at the time the train starts to passfrom block 2 into block 3, block 6 is occupied. In that event, when the first mentioned train starts to enter block 3, the magnet of track relay TR will be deenergized, and the circuit of conductor C through the c armature of relay-TR, and the front contact correspond- ISO ing to that armature, will be broken; consequently, the magnet of relay L will not be energized upon the entry of the first mentioned train into block 3, and, when the train proceeds through block 3 and reaches the entrance of block 4, relay L will not have closed the alternating current circuit to the fourth rail section T (supposing block 6 still to be occupied, or not to have been vacated for a time corresponding to that to which relay Lthas been set) and therefore the train seeking to enter block 4 from block 3 will be brought to rest by the means hereinafter described.

When the first mentioned train passes from block 2 into block 3, the magnet of relay L will, in general, already have beenenergized and the alternating circuit from secondary s of transformer S will have struction indicated is a practical one.

will be understood that the train control been applied to fourth rail section T 8 through the front contact of relay L simi= TR will maintain the circuit through the magnet of relay L*such provision being necessary since, when the train passes completely out of block 3 the magnet of relay TR will be energized and its armature contacts held in attracted position. When the train has passed completely out of block 4 the magnet of relay TR"= will be energized inturn, its armature contact oints held in attracted position, and, therefore, the magnet of relay Lwill be denergized.

It will be seen that by the expedient of extending backward the circuit of each line relay L L etc., to a contact of a. track relay corresponding to a preceding block, I

obtain a control of the speed of the train passing through that preceding block; for should the train exceed the predetermined speed it will be arrested upon entry into the block to which the particular line relay under consideration belongs.

As indicated particularly in Fig. 3, the train control conductor T may be supported from, though insulated from, the propulsion current conductor T; and the main train contact shoes MS may carry train control circuit shoes SS arranged to contact with the train control conductor T;shoes MS and SS being of course, insulated one from another. I have not attempted in Fig. 3 to show the actual construction of the contact shoes, but have merely indicated the same diagrammatically; though the conconductor T is not necessarily mounted upon the third rail T, as indicated in Fig. 3, but may be supported in any other suitable manner. 7

Referring now to Fig. 2: In the case of most electrically propelled cars used where automatic signal systems, and, particularly, automatic train stopping systems are desired, the running of the car is: co ntro]led supply of current to the motors of that car by a circuit such as representedin'part in Fig. 2 by conductors SB and SB"; 'lhis'is particularly. true in the case of cars ope'rated according to the well known multiple unit system; whereby motor controllersgof all the cars of a train may be opor the supply of current to the motors of any othercar of the train. The circuit SB SB may be understood as representing, diagrzfmmatically, the entire ordinary control system of the car or train. I have not shown any source of current for this circuit SB SB, but it will be understood of course that a suitable source of current supply is provided for that circuit, as in ordinary practice. It will further be understood that, in order that the car or train may proceed, this circuit S13 SB must be closed. For holding this circuit closed, so far as my present train control system is concerned, a relay GB is provided, the armature GB of which maybe raised (usually by hand) to close Contact between terminals of the conductorsSB and SB". This relay GB is, in practice, a cut-out relay, the magnet of which does not have sufficient power to raise the armature CB, when that armature is down, but does have power to hold that armature CB elevated once that armature has been raised by hand or otherwise, until the circuit through the magnet of the relay is broken. 12 designates the air brake line of the car and V a valve in this line, connected to the armature GB in such manner that that armature, when in elevated position, holds the valve V- closed (the air brake systm being understood to be of that type wherein the brakes are set by the opening One or more switches X and Y are located at suitable points, usually points from which .thecar or train is to be controlled. In the drawings these switches are shown in the normal or non-running position. To each such switch is connected a brake-line valve, V or V, which is normally closed. Other switches A and B controlling valves V and V which are normally open, will be referred to hereafter.

Suppose that the car or train is to be operated from the point at which switch X is located. The operator first actuates switch X so as to open contact A of switch X and to close contact A of switch X, thereby opening valve V He then raises the armature CB, thereby closing valve V and clos ing circuit SB SB so far as the apparatus shown in Fig. 2 is concerned.

Train control current may be understood to be received through one or the other of gized its armature is held in attracted po-- sition and circuit closed between the termione of the shoes SS and the stop relay GB to one of the main shoes MS and thence to third rail T be opened (and such circuit may be opened, as previously explained, by one of the delay action relays L relay CB will be de'e'nergized and its armature CB will fall, opening the air brake line valve V, which line will then find vent through valves V and V so bringing the train to rest. With the parts in this position, the train may nevertheless be permitted to proceed if the operator closes the switch A which clggesa, circuit from conductor SB through conductor SB switch A conductor S13 contact B of switch Y, to conductor S13 this circuit bridgin the gap between the contacts of relay B due to the dropping of the armature of that relay.

From the above description it will be ap-, parent that trains passing over the track are under automatic control to the extent that not only will a train be stopped if it enters a block section-two sections behind a block section already occupied, but also if it passes through. a block section at a higher speed than that for which the delay action relay (L etc.,) of the block "section next ahead has been set; the stopping of the train in either such case being due to the failure of the appropriate delay action relay to complete the circuit of the secondary s of the corresponding transformer through the fourth rail, shoes SS, the coils of relay CB, shoes MS andthe third rail T. Never theless a train so stopped will be permitted to proceed if an emergency switch such as A or B be closed. I

In my said prior application Serial No. 47,581, I have disclosed a system. wherein alternating current is used for train control and direct current is used for train propulsion, or vice versa, both currents passing through the third rail, condensers and indu'ctance bonds being provided to isolate the direct current circuits from the alternating. current circuits, and-vice versa.

By the present invention, and by such simple means as the employment of a light fourth rail, conveniently carried by the third rail, I avoid occasion for the use of such isolating means as the condensers and inductance bonds ofmy said prior application, with consequent great simplification. Also, according to my present invention the return for the alternating current circuits, employed for train control is not through the wheels and axles ofthe car and the track rails, and therefore the voltage in the track circuits may be kept small. The dropping of a crow-bar or like conductor across either the track rails or across the third and fourth rails can do nothing more than cause the stoppage of a train; it cannot cause the blowing of fuses etc.

Current for the track circuits controlling relays TR and TR, etc., may be supplied in any suitable manner; Ivhave indicated for this purpose additional sections a of the transformers, connected to the track rails, as in my said prior application.

Owing to the complete independence of the propulsion circuit and the train control circuit, it is not necessary as in my said prior application that one of these circuits be an alternating current circuit and the other a direct current circuit; both circuits may be of the same character and, essentially, either may bedirect current circuits, and both may be direct current circuits if preferred, or both may be alternating current circuits if preferred.

What I claim is 1. A railway train control system comprising a propulsion current conductor and a train control circuit conductor, insulated one from another and the latter divided into sections, in combination with a train circuit connected on one side to the train control conductor and on the .other side to the propulsion current conductor and including train control means, and means for supplying train control current to said train control conductor and propulsion current "conductor as parts of the train control circuit.

2. A railway train control system comprising a propulsion current conductor and I control conductor and on the other side to the propulsion current conductor, and including a train control relay and means for supplying train control current to said train control conductor and propulsion current conductor, as parts of the train control circuit.

3. A railway train control system comprising a propulsion current conductor and a train control circuit conductor, insulated one from another, and thelat'ter divided into sections, in combination with a train circuit connected on one side to the train control conductor and on the other side to the propulsion current conductor, including a train control relay and means for supplying train control current to said train control conductor and propulsion current conductor, as parts of the train control circuit, and a brake line' comprising means operated by said relay forapplying the brakes.

4. A railway train control system comprising in combination a propulsion ourrent conductor and a train control circuit conductor, the latter divided into sections, means for supplying train control current to said two conductors as opposite sides of a train control circuit, and a time-element device controlling such supply of current,

two contact members, one for one of such conductors and the other for the other of said conductors, and train control means included in such train circuit.

6. A railway train control system comprising track rails one of which is divided into block sections, a propulsion current conductor and a train control circuit conductor, extending along the track and in proximity to said track rails, the train control circuit conductor divided into block sections, track circuits passing through such track ,rails and switches operated thereby, means for the supply of train con-. trol current to said propulsion current conductor and train control circuit conductor as opposite sides of a train control circuit,

, delay action means operated by said switches and controlling the supply of train control current to said conductors, in combination with a train circuit connected on one side to the train control conductor, and on the other side to the propulsion current conductor, and train control means included in said circuit, the train control circuit being entirely independent of the track rails.

7. A railway train control system comprising in combination a track," two 0011- ductors extending along said track, one of said conductors being divided into block sections, means for the supply of train control current to said conductors as opposite sides of a train control circuit, a time element circuit controller controlling such supply of current, and train actuated means for each block, each such train actuated means controlling the said time element circuit controller of its own block and the said time element circuit controller of a block in advance.

8. A railway train control system comprising in combination a track, two conductors extending along said track, one of said conductors being divided into block sections, means forthe supply of train control current to said conductors as oppositevsides of a train control circuit, a time element circuit controller'controlling such supply of current and train actuated means for each block, each such train actuated means controlling the said time element circuit controller of its own block and the said time element circuit controller of a block in advance and the said time element circuit controller of a block in rear.

9. A railway train control system comprising "in combination a track, two conductors extending along said track, one of said conductors being divided into block sections, means for the supply of train control current to said conductors as opposite sides of a train control'circuit, a time element circuit controller controlling such supply of current, and train actuated means for each block, each such train actuated means controllin the said time element circuit controller of its own block and the said time element circuit controller of a block in advance and the said time element circuit controller of a block in rear, the time element circuit controller of each block also controlling the time element circuit controller of a block in the rear.

Intestimony whereof I have signed this specification in the presence of two subscribing witnesses.

, JOHN o. McDONALD.

Witnesses:

H. M. -MA'RBER,

D. A. DAvms.

Images