US1596223A - Train indication system - Google Patents

Description

Aug. 17, 1926. 1,596,223

G. C. WHITNEY TRAIN INDI CATION SYSTEM Original Filed March 27. 1924 VE/V TUE" Patented Aug. 17, 1926.

, rseazza GILBERT C. \VHITNEY, OF NEW YORK, N. Y.

TRAIN INDICATION SYtiTEM.

Original application filed March 27, 1924, Serial No. 702,262.

February 11, 1925.

This invention relates to train 'describers and train indicators in general wherein means are provided to indicate the position or describe the movement of a train or car on a railway track and in particular to novel means for accomplishing the aforementioned results with minimum apparatus especially when installed on tracks not equipped with a signal system.

This present application is a division of my co-pending application filed March 27, 1924, Serial No. 7 02,262, for train indication system.

In my above mentioned applicationI have set forth, at length, the general objects and operation of my invention as carried into eflect or superposed on existing signalled railway track territory and it is assumed that reference to said application'will be had.

In this divisional application I have shown my invention arranged in a system of train indication, without the customary track rail insulated joints in general use in railway signaling and indication systems and therefore my system readily permits the use of both rails of the track for the propulsion system on electrically operated railways :thus the general objects appear and additional objects will be disclosed as the specification proceeds and I will point out the novel features in the appended claims.

I have provided two figures to clearly portray the preferred application and simplify the operation description but I wish it to be understood that I do not restrlct or limit myself to such application of my invention-it is so shown merely to disclose the broad idea underlying my invention. It will be observed that the reference characters are not consecutive and this is because I have preferred that this invention be disclosed and described with the same reference characters for similar parts as my previously referred to application and thus make this disclosure concise as well clearly understood.

'Fig.v 1' is a diagrammatic illustration of my invention.

Fig. 2 is a diagram representing the value and variation of current flow in the indie-a tion circuits due to train travelalong the track sectien. in. 2 may also sea en-men {I b a shew variance. as r illuminatin smit Divided and this application filed Serial No. I 8,401.

ted by the indicator lamps as the train proceeds along the track section.

Referring to the drawing-In Fig. 1, I have shown the two rails 6, T, of a railway track as continuous but it will be appreciat ed that they may be made in various lengths and connected together by splice plates andbonded or otherwise to form a continuous rail circuit as is customary but, track rails 6, 7, remain electrically insulated (in so far as the indication circuit, hereinafter eX- plained, is concerned) from each other by the wood ties or other appropriate means in general use.

As the means rent supply on the track rails for the working of my invention I have shown thre. transformers 9 to supply energy to the track at selected points, approximately though not necessarily equidistant. Said transformers 9 receive energy from source of energy sup ply alternator 18 by way of power wires 17, 16, and branch wires 15, 14. The secondary windings of transformers 9 are connected to the track rails 7, 6, by means of track wires 11, 10. Connected in series with each of the secondary windings of transformers 9, I show primary windings 35 of transmitter transformers 34 and inductively coupled to said primary windings 35, I show transmitter secondary windings 36, each of which is included in a transmission circuit 37, 38. Included at the receiver end of said transmission circuits I show receiver transformers 39 to the secondary windings of which are shown connected indicator lamps 42. I show track rails 6, 7, short-circuited by reactances C D E at suitable places. approxi mately at mid-points, between the points where energy supply track wires 10, 11 are connected to said track rails. The characteristics of all apparatus is proportioned such that the induced current supplied to the respective indicator lamps 42 is amaximum when the track rails 6, 7, are shortcircuit-ed, as by a train wheel shunt, at the corresponding points of energy supply trackwires 10, 11, and said maximum induced current flow to the respective lamp 42 varies as said train wheel shunt moves either way from said points with slow reduction until said train wheel shunt passes a track short-circuiting actarlce and thereafter at a rapidly ii easing rate,

rea

to impress alternating curployed, and as illustrated in Fig. 2, wherein a train is assumed to be a point only for the purpose of clarity.

From the foregoing description it will be evident that the movement of the train is synchronously indicated by the change in illumination caused by the change in value of induced current supplied to said lamp as the train moves along the track section and without the use of insulated joints in the other appropriate means track rails.

Hereinbefore, l have referred to the fact of track rails 6 and 7 being electrically insulated from each other by the wood ties or and it will be evident that, even though the wood ties are an insulator when dry, they may be wet due to rain and their value as an insitilator be thereby impaired. it is customary, therefore, to apply only low voltages to the track rails 6 and 7 and especially so with this type of system without insulated track rail joints and with indication transmitters 3 1- at comparatively close intervals, as dictated by the spacing between trains. It is the general custom to arrange the indicator lamps at a central point for a given territory which may be of considerable extent and, owing to the great number oi circuits involved, economy demands that small wires be used in the transmission circuit and nat urally only a small transmission current can be tolerated, otherwise the loss in transmission would not only be prohibitive but would interfere with the ind'cation as hereinafter pointed out. Starting then, with the necessarily low track circuit voltage I provide inductive coupling to act as a stepup transformer to provide a higher trans mission circuit voltage and the corresponding transmission current for indication purposes is of the order of 0.015 ampere and less. Now, as is welll :nown, an indication lamp of high voltage and low wattage (one (1) Watt and less) is not commercially possible because of the inability to provide a lamp filament whichwill heat on a current flow of the above mentioned order of 0.015 ampere and less and accordingly I provide receiver transformer 39 of the step-down type and wherein the resultant induced indicating current flow to lamp 4-2 is of the order of 0.080 to 0.350 ampere and at an operating voltage of from approximately one (1) volt to live (5) volts. Thus it will be evident that, in the use of transformer 39, means have been provided to etlect an indication on a very small transmitted power and with a minimum in the losses incident to transmission. A minimum in the losses of transmission is important for the reason that the var ation in currentflow in the rail circuit, as between the train or car at several points within the influence territor of an indication lamp, is small and every last effort must be made to conserve the results, of the variation, during transmission to the indication device.

Referring to Fig. 2, the solid irregular line traces out the value of current supply to indicator lamp 4201) as the train wheel shunt approaches and traverses track sec tions Cl), said current reaching a maximum when. the train wheel shunt is adjacent track wires 10, 11, for that section and reachinga practical minimum rapidly, as aforesaid, when and as said train wheel shunt passes a short distance beyond said section: similarly, the dot and dash line illustrates similar conditions for the traclr' section and corresponding indicator lamp DE: and so on to the end of the system, as will be appreciated. Obviously, a train is not a point and the representative lines in the diagram will broaden and overlap as the train point takes on the dimension, length.

It will be understood that the variation in the induced current flow to the lamp as the train wheel shunt moves on the track railsis due to the fact of the rail resistance being increased or decreased in the circuit which includes winding 35 for the respective section.

Vi hile, it may be assumed that the characteristic variation of illumination is the same for train position ineach halt ot a track section, it will be appreciated that the direction of movement of the train is emphasized by the indication of the lamps for the adjacent track sections.

it should be noted that track reactances C D and E may be eliminated in which event the operation of my system will be less contrastly distinctive.

Attention is directed to the fact that, while I have shown, in F 2, that the irregular lines represent the variation in currentsupply to the lamp, they also represent the variation of the illumination of the respective indicator. lamps as a car proceeds over the track section. I desire it to be distinctly understood that, although. the irregular lines oi Fig. 2, show a variation in illumination between the extremes, as the car passes. over the track section (that is, be tween no illumination and full illumina tion) the indicator lamps may be partially illuminated at all times, for example. with 20% illumination, when the track section is not occupied by a car, andL with illumination variation between 20% 'llumination as a base (at the time the car enters the traclr section) to 100% illumination when the car wheel shunt is on the track at the point where track wires 10 and 11 for the respective section are attached-all as determined by the design of apparatus in each installation. The fact that the lamps may be arranged to be partially illuminated at all times provides a means for continuously inequipped track dicating that the system is in working order.

I wish it to be understood that, while I have only illustrated two completely sect-ions and portions of two adjacent sections, in practice a complete territory would be equipped and the indicator lamps assembled in an indicator board or track model diagram at the desired location.

The transmission circuit 37, 58, is generally composed of No. 19 A. N. G. or smaller wires owing to the fact that on account of low wattage lamps being used the small line current permits of using small conductors, thus contributing to low installation costs.

Obviously, the arrangements and illustrations which I have shown and described are merely illustrative and do not exhaust the various embodiments and forms which I have made, or that anyone ordinarily skilled in this art could make without departing from the novelty,'spirit and scope of the broad idea of means underlying my invention.

Having thus described my claim and desire to secure by ent:

1. A train indication system; characterized by a plurality of sources of energy impressed upon the track rails of a railway track, each source of energy having an inductive coupling included in series therewith, and an indicator lamp inductively coupled to each inductive coupling, each indicator lamp indicating the presence and movement of a car on said railway track, both rails of said track electrically continuous and without insulated joints.

2. A train indication system; characterized by a section of railway track bot-h rails of which are maintained electrically coninvention I Letters Pattinuous and without insulated joints, a

source of energy impressed upon the track rails at a plurality of points, an inductive coupling included in an energy supply wire to each dicator lamp inductively coupled to each inductive coupling, for synchronously indicating the presence and movement of a car on said railway track.

3. A train indication system comprised of a section of railway track, a source of energy, transformers for supplying said energy to said track at a plurality of points, reactance elements bridging the rails of said track between the points of energy supply, and means for utilizing said energy to indicate the presence and movement of a train on said section of railway track, both rails of said track electrically continuous and without insulated joints.

4. A train indication system comprised of a section of railway track, a source of energy, transformers for supplying said energy to said track section at a plurality of points, an indication transmitter connected of said points, and an 111-' in series with each of said transformers, and

with each of said indication transmitters, the movement of variation in light emitted by said lamp, both rails of said track electrically continuous and without insulated joints.

5. A train indication system comprised of a section of railway track, asource of energy, transformers for supplying said energy to said track section at a plurality of points, an indication transmitter in series with the energy supply to the track rails of said track, and an indication receiver for each transmitter, each transmitter responsively controlling the corresponding receiver as a train moves on said section of railway track, each receiver indicating the movement of a train on said section of railway track, both rails of said track electrically continuous and without insulated joints.

6. A train indication system, comprised of a section of railway track, a source 0 energy, transformers for supplying said energy to said track section at a plurality of points, indication transmitters inductively coupled to said supply, a transmission circuit for each transmitter, indication means synchronously responsive to variations in the energy flow in said transmission circuit caused by the movement of a train on said section of railway track, both rails of said track electrically continuous and Without insulated joints.

7. A train indication system comprised of a section of railway track, a source of energy, transformers for supplying said energy to said track at a plurality of points, indication transmitters inductively coupled to said track, and indication receivers including indicator lamps inductively coupled with said transmitters, said lamps energized from said source and with partial illumination when said track is unoccupied, said illumination varying as a car moves on said track, both rails of said track electrically continuous and without insulated joints.

8. A train indication system comprised of a section of railway track, a source of energy, a plurality of transformers for supplying said energy to said track at a plurality of points, transformers in series in the energy supply to said track, transformers connected to said second mentioned transformers, and indicator lamps connected to said third mentioned transformers, both rails of said track section electrically continuous and without insulated joints.

9. A train indication system comprised of a section of railway track. a source of energy, transformers for supplying said energy to said track at a plurality of points, indication transmitters inductively coupled to said track, and indication receivers connected to said transmitters, each receiver at a train on said section by and remotely, located times indicating the presence of a train on said track and at times continuously indicating the movement of a train on said track, both rails of said track electrically continuous and Without insulated joints.

10; A train indication system comprised of a section of railway track, a source of en ergy, transformers for supplying said energ r to-said track at a plurality of points, transformers in series with the secondary of the first mentioned transformers, transmission circuits in series with the secondary of the second mentioned transformers, a third transformer in series with each of said transmission circuits, and indicator lamps connected to the secondary of said third transformers, both rails of said track electrically continuous and without insulated joints.

11. The invention set forth in claim 2, distinguished by the indicator lamps being assembled to form a train indicator diagram and arranged in consecutive order.

Signed at Brooklyn in the county of Kings and State of New York.

GILBERT C. lVI-IITNE Y.

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