US1109880A

US1109880A - Signaling system for railways.

Info

Publication number: US1109880A
Application number: US30320106A
Authority: US
Inventors: Louis H Thullen
Original assignee: Union Switch and Signal Inc
Current assignee: Hitachi Rail STS USA Inc
Priority date: 1906-02-27
Filing date: 1906-02-27
Publication date: 1914-09-08
Anticipated expiration: 1931-09-08

Description

L. H. THUL'LIEN.

SIGNALING SYSTEM FOR RAILWAYS.

AFPLIOATIOR' FILED AUG. 22, 1904. RENEWED FEB. 27, 1906. 1

1,109,880. Patented Sept-8, 1914 Lou sa. trnULL'nn, 'nnenwoon PARK, rnunsnvamanssrenon 'ro THE UNION swrrcniaszcnsn COMPANY, or swxssvann, PENNSYLVANIA, A conronarron or rnnn's'vrvanra.

' srenamive SYSTEM FOR amwns.

To allwh'o'initmayconcern:

Be .it known that I, LOUIS H. THULLEN, a citizen of the United States, residingat Edgewood Park, in the'county'of Allegheny and Stat-cot Pennsylvania, have invented GGItalIIYIlE-W and useful Improvements in Signaling" y'stems [for Railways,of which the following is a specification.

' j'My'invent-ionrel-ates to s1gnaling systems Y titres thereof in claims.

for railways, and it is particularly adapted for use in connection with electric-railways wherein'the track rails are employed'as a return path forthe propulsion current used for the-car on vehi'cle motors; I will-(le scribe I a signaling system embodying-any invention and-= its application to an electric railwayand then point out the novel fea- Th'e accom'p'anying drawing is a diagrammaticirepresentation of a portion ofa railway: and a signaling system embodying my invention. 1 a

Referring now tothe drawing, A desig nates a portion of a railway having its opposite lines of railsprovided with insulation a'at suitable points to form what are technically known in the art as track "or block sections. I

D designates a generator for supplying through adinemonductor d propulsion current for the motors carried by cars or vehi cles traveling'along the railway. The generator D- may be a direct current generator or an alternating current generator. Each car or vehicle carrying a motor is provided with a trolley (Z or other equivalent device which contacts with the conductor (1 as the car or vehicles travel along the railway. The return for the propulsion current from the motors is through the track rails and to permit of this and thus save the cost of line conductors or cables for this purpose, I provide inductive windings F, F, at each insulation point along the railway. These .inductivewindings and their arrangement are set forth in my application for patents filed- Februa-ry 5th, 1904, Serial Nos. 192,145 and 192,146. It-is suflicient to here state that r the windings be so constructed and arranged that the propulsion current of any description will freelv pass through them without appreciably afiecting them in any way,while the alternating current for track circuit purposes will be impeded and confined in its Specification of Iletters Patent. I Application filed August 22, 1904, Serial No. 221,774. Renewed February 2'2, 1906. SeriaYNo. 303,201.

ma a Sept. 8, 1914.

erated or controlled device which is 0on 'trolledfrom the track circuit of the track section: the drawings I have shown two railwa'y signals S, S each of which comand an automatically operated mechanism of any well-known type. Each tracksection is'provided with a track circuit-which, as usual,-comprises a source of current, the op posite or portions of the opposite lines of rails and translating devices each in the form of a relay which controls a local circuit. The source of current for each track circuit may be any desired and as here shown mm the form of a transformer T to be hereinafter referred to. The primary winding t of each transformer is in circuit with mains c,- 0 extending along the railway from an alternating signaling current generator A. 0., while its secondary t is .connected with the track rails of itstrack and B may be of any desired construction .provided it is responsive to the current intended for its operation. Preferably each translating device will be substantially of the form shownand described in my application for patent filed October 13th, 1903, Serial No. 176,836. The local circuit or other circuit which is controlled by the translating device includes a source of current and the electrically operated or an elecnal. The source of current for the local circuitmay be any desired, and as here shown is obtained from the direct current generator D. In the event that alternating current is used forpropelling the, cars, the alternating signaling current will be of a different' frequency;

Heretofore in signaling systems and espe- One pole of the generator prises a semaphore or other signal device trically controlled device of the railway-Sigsection. The translating device or relays R I ci'ally in block signaling systems, it is usual to place the source of signaling current at one end of the track section, usually at the exit end, and the translating device or relay at the other or entrance end. In the present invention 1, preferaltily employ two translating devices R, It, for each track section and locate them preferably at or near the ends oi the track section and the source of signaling current'supply for the track circuit between the ends of the track sections preferably at a point midway of the ends of the track section. The object in locating the source of current, in this instance the transformer T, between the translating'devices R, R is as follows In all track circuits it is desirable that the amount of current and the E. M. F. thereof be kept as low as possible on account of the leakage from the track rails and for other reasons economical and otherwise. Especially is this true of-alternating current, for, as is well known, the track rails olfer considerable impedance to. an alternating current which varies from 1 to an infi mte number of times the ohmic resistance,

depending upon the frequency otthe current. At ordinary frequency (from 25 to 133 cycles) this impedance might approximately be 20 times the ohmic resistance. Therefore by placing the supply .of alternating current at one end of a track section and the translating device at the other end thereof, a comparatively high-E. M. Rot alternating current is required at the source of current to supply the necessary E. M. F. to

operate the translating device. For exam-- ple, if the transformer is at oneend of a track section and the translating device at the other end, the A. C. potential at the transformer end will be from Gto 12 times greater than the A. C. potential at the other, and therefore, there is a likelihood of the insulating joints breaking down between two adjacent track sections, and the transformer furnishing current to the translating device in the adjacent track section. To overcome this and other objections I locate the source of alternating signaling current (in this case the transformer ata point between the translating devices, referably at a point midway of the, endso the track section. ll ith this arrangement the high alternating E. M. F. or potential is atsubstantially the middle of the. track section and substantially the same alternating current E. M. F. is obtained at the terminals of both translating devices and, at the ends of the track section. l/Vith this arrangement of the transformer a much lowerE. M. F. of alternating current could be used in the track circuit which is highly desirable, or the length of the track section could be double at the same A. C. potential as used when the transformer is at one end of the block.

What I claim as my invention is:

' 2.111 a signaling system for'electric rail-- ways inwhich the track rails are employed as a return path for the propulsion current, the combination with a serles of insulated track sections, of inductive windings arranged to be unaffectedby the passage of the propulsion current from one track section to another but to afford a path of high impedance to the passage of alternating signaling current, and a track circuit for each track section which comprises a source of alternating signaling current located between the ends of the track. section and adapted to deliver an alternating signaling current at the ends of the track section of lower potential than at its point of connectionwith the track rails of the track section.

3. The combination in a signaling system for electric railways,-the-track rails of which are used as a return for the propulsion cur rent, and are divided into insulated. sections,

of inductive windings for connecting the track rails of adjacent track sections, a trackcircuit for each track section which com prises at least two translating devices one eing located at about one end of thetrack circuit and the other located. at about the other end of the track circuit and a source of alternating current, said source of ,alternat ing current bein located at a point in the track circuit w 'erebyj substantially equal alternating current potentials will be supplied the track rails of the track section at the terminals of each inductive .winding at the ends of the track section.

a 4:. The combination in a signaling system for electric railways, the track rails of which are used as a return for the propulsion current and are divided into insulated track sections, an inductive winding at each track section which permits. of the passage of the propulsion current, and a track circuit for each track section comprising at least two relays one being located at about one end of the track circuit andthe other located at about the other end of the track circuit and a source of alternatingcurrent located in the track section at a point to produce a higher alternating currentpotential between the track rails than that produced at the inductive windings at the ends of, the track section.

5. The combination in a signaling system for electric railways, the track ralls of which are used as a return for the ropulsion current and are divided into insulated track sections, inductive windings at each track section which afiord a path of highv impedproduce a higher alternating'current poten-;

tial between the track rails than that produced at the inductive windings at the ends of the track section.

6. In combination with a railway, the track rails of which are divided by insulation into track sections and form a part of the return path for the car propulsion current, a pair of inductive windings placed at each insulation point, one winding being connected with the track rails of one track section and the other winding being connected with the track rails at the adjacent track section, and the middle points of adjacent windings beingelectrically connected, and a track circuit for each track section, each track section comprising a relay device to control a railway signal and a source of signaling current located at about the middle point of the track circuit.

7. In combination with a railway the track rails of which are divided by insulation into track sections and form a part of the return path for the car propulsion current, a pair of inductive windings placed at each insulation point, one winding being connected with the track rails of one track section and the other winding being connected with the track rails of the adjacent track section, and the middle points of adjacent windings being electrically connected, and a track circuit for each track section comprising a source of alternating signaling current located at a point in the track section to produce a higher alternating cur-- rent potential between the track rails than that produced at the inductive windings .at the ends of the track section;

8. In a signaling system for electric railways, the combination with a source of power current, a transmission system therefor of which both track rails form a part, a plurality oftrack sections, means for conducting the. propulsion current from the track rails of one track section to an adjacent track section, a source'of signaling current for eachblock section located at about the middle point of the block section, a railway signal for each block section, a control-,

ling means for said railway signal energized from the track, the energy being taken from the track at one portion of theblo'ck section,

and a second controlling means'for; said railway signal energized from the track, the

energy being taken from the track at another portion of the block, section.

9. In a signaling system for electric railways, the combination with a source of power current, a transmission system therefor of which bothtrack rails form apart, a plurality of track sections, means for conducting the propulsion current from the track rails of onetrack section to an adjacent track section,.a source of signaling current for each block section, located at about the middle point of the block section, a railway signal for each block section, a controlling means for saidrailway signal at one end of a block section, a controlling means for the r ailwaylsignal' at the other end of the same block section, and both of said 'controlling means energized from the track by the signaling current of the block section.

10. The combination in a'signaling system for railways, of track circuits formed in part by the track rails of the railway, a source of alternating signaling current connected acrossthetrack rails and located about the middle of the track circuit, two translating devices for each track circuit and complet-- ing said track circuit, one translating device being located at oneend of the track circuit and the other translating device being located at the other end of the track circuit, and railway signals, one railway signal being provided for each track circuit and controlled byboth translating devices of its track circuit.

11. In combination with an electric rail-' way, a source of power current; vehicles opwhich the vehicles make moving contact, one

of which is formed by the track; signal-circuits of which the rails of the track form two sides; signal devices for each signal circuit one such signal device being located source of alternating signaling current for each signal circuit connected across the track-rails'andlocated at about the middle of each signal circuit, and means for limiting the alternating signaling currents to the several signal circuits.

at about each end of the track circuit; a i

.13. In combination with an electric rail-,

way, a source of powercurrent; vehicles up 4 h 1109 sac erated' thereby; a circuitifor:said=powe12cur located at about the midiile of each-signal rent comprising two conductors: with which cimuit, and cross-bonds located ,Mabmt the the vehicles-make meving contacts, one-10f each of tfiesignal circuits, which is formed by the track;vsignal circu its In testimony whereof I have signed my 5 of which the rails of the track form.twn namasto this s ecification in thwpmsenceof 15 sides; signaldevices for each signal circuit two subscribe 4 Witnesses.- one such signal dvice, being locatedlat about LOUIS H 'IHUILLELL- each end of the trackcirouit, a, source: of'af- Witnesses,

ternating signaling current for each signal GnohEh misza, 10 circuit, connected across'the trwckeralls .and-

WDGNHRi Gopie: of this-patent'may be owned for five cent: each, -by ai dressfl1:lbw-commoner oz rmtentiy wuhlngtqu; ID. 0;?