No. 880,136. v PATENTED FEB. 25, 1908. J. A. GEHRUNG.
SIGNAL SYSTEM. APPLIGATION FILED BBB. 2, 1907.
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JULIEN A. GEHRUNG, OF NEW-YORK, N. Y.
` SIGNAL SYSTEM.
Specification of Letters Patent.
Patented Feb. 25, 1908.
Application filed February 2| 1907. Serial No. 355.369.
despatcher.
It is impractical, especially .in the more r thinly populated sections of. the United States, to have the block signals and stations and operators at as fre uent intervals,
i .as are provided in more thick y settled com- Yno munities. As a matter of fact, nearly all the railroad mileage of the United Statesfis un protected by signals of any sort.
It is the purpose of the present invention to provide a signal system adapted to suit all the requirements of railroad traffic, and which is so simple in its installation, and which requires so little superintendence, that it is adapted to the most rural and undeveloped sections of the country where railroads are used. The system which I have developed secures a semaphore control oi the railroad line under the entire surveillance of the despatcher at a city terminus, and further rovides for telegraphic `communication to t e train at whatever point of the line it may be. This is further accomplished by two simple wires or conductors extending along the roadway. Finally,I and as I consider most important of all, the system is such as to always provide an indication or check on its accuracy,l so that any condition, such as broken wires, or short circuited wires, Aor leakage, or any other defect, is at o'nce notified to tlie despatchers oflice, who is thereu on able to have it promptly repaired. ese are all the absoutely essential Vre uirements oi a railroad signal system,name y, that it should answer traffic conditions by a limited number of wires, and give notification to allh parties in case of any iailure, defect or breakage whatsoever. Incidental and additional features of the invention Willappear in connection with the following description, particularly the way in which all inductance and electrostatic capacity features of the line are wholly done away with, and also-the manner of controlmatic telephone and telegraph semaphore station for establishing tele- .ling the circuits by which a high potential break, liable to cause a spark, is never made at any point, or in any vdelicate instrument where it is liable to cause damage.
In the drawings: Figure 1 is a dia rammatic view showing a complete instal ation embodyingl the principles of my invention g Figs. 2 and 3 are detail views 'of certain appa'- ratus employed.
The showing in Fig. l is, of course, almost exclusively diagrammatic, it being evident that in practice many details and appurtenances would be desirable, and would, be added to secure specialriunctions which might be desired for any particular conditions. lFor example, in lpractice it might be thought desirable to have lelectric bells at all the sema' phore signals, which would ring whenever the semaphore was at danger. It might also be thought desirable to have special auto.
vsets at' each graphic or telephonic communication With the despatchers office therefrom. It also might be thought desirable to have special devices for ringing alarm signals in the engine cab, or actuating train stops, in case a semaphore signal at danger was passed. But all of these appurtenances and'details are always a plicable wherever they are desired, and
Ia though I contemplate their use in ractice I have eliminated all of them from t e present description of the invention, since the essential features, in other words, the fundamental idea or-princi-ple, 'operates in identically the same way whether or not these additional details and appurtenances are adopted. In my4 companion a plication, Serial No. 357,514 iiled herewit i, I have, however, illustrated some of these embellishments in order .that their mode of application may be erectly clear.
In or er to make the essential principles of the invention plain, four semaphorestations willbe considered. These stations are represented in Fig. l, at I, II, III and IV, it being understood that in practice as man stations as desired would Cbe provided, and ocated at suitably spaced intervals along the division or line of railway, the traiiic o t'vwhich is desired toA be entirely controlled from a single despatchers oilice at'a city terminal of the line. A indicates the despatchers olice in Fig. 1.
Means are provided at the despatchersv station A for generating a continuous electric current, andfor reasons which will hereinafter a pear, a current of quite high voltage. The vo tage would, of course, vary with ditferent installations; 500, or even 1,500, volts is not an unreasonable igure. l have shown a dynamo 5, at the despatchers station for this purpose. Extendingfrom the despatchers oflice are two lines L and L2, which parallel the track throughout the entire length of the railroad. At the required points4 these lines connect with the semaphore stations I, ll, 111 and 1V.\ Each semaphore station includes magnetic devices in the' circuit of the line L and signal transmitting devices in the circuit of the line L2. The magnetic devices in the circuit of the line L constitute' selective signaling means. For this purpose there may be provided ordinary electro magnets', 7, 7, 8, 8, 9 and 9, all in series with one another, and with the line L. tion ll, 7, 8, at station Il, 8, 9, at station lll, and 9 at station 1V. Each of these pairs of magnets coperate in a special way together to control local circuits at the semaphore stations. A ractical arrangement of these magnets is s own in Figs. 2 and 3. Each magnet has acentral iron 4core 10, and any Leshaped extension 11, to which is pivoted an armature .12. 13 denotes a stop or adjustment by which the normal position of the armature is regulated with respect to the core orpole 10. 'Each armature has a block 14' of ii'ber or,insulating material and each of these blocks has a me.- tallic clip, denominated 15 and 15-, for the respective armatures, each of which projects toward the other, but in overlapping relation, as shown'in Fig. 2. The relationis -such that the clips make electrical contact whenthe lowermost one is alone attracted, but in case both armatures are simultaneously attracted, the open circuit relation between the clips is maintained. In Figs. 2 and 3 each armatureY has a pair of clips which in some cases have a special Jfunction as will later appear in connection with the recording ap aratus o,'o2, o3, o4, o5. One magnet is woun with a greater number of turns of wire than the other, or one may be,shunted by resistances, or its Aarmature more strongly restrained, so' as to'be less sensitive. 11n the drawings `this is indicated by having the windingor1 one magnet longer than that of the other. Since all the magnets are connected in the same series circuit, they are best wound with wire of unvaryingdiameter. The relation of their resistances is immaterial, so'long as they are all in the same series circuit.
Referring now again to Fig. 1, Vit will be seen that the winding 7 has fewer turns than the winding 6. The windingzj7ris, however, exactly like 'the winding 7, -'or wound to be lThe -magnets 6 and 7 are at sta-y .of the circuit of the line L.
case.
esame actuated by the same strength of current. The winding 8 has fewer number of turns than 7 or 7, but 8 is exactly like 8. In like manner 9 and 9 -are alike, but of fewer turns than windingsS and 8. The line L is grounded beyond the lfinal winding 9, or
otherwise connected to a return wire or circuit.
At the despatchers station A there is' provided a switch orequivalent device 16, by
which the current from the dynamo 5 can be switch for connecting the line L or L2 to a source of potential, is all thatv is required. There is also provided at the despatchers station As a resistance or current varying device. This is most conveniently in the form ofswitches 1, 2, 8, 4, which are capable of cutting resistances R, R2 and R3 in and out 1t is evident that if switch No. 4 is closed, all of the resistancesRQRz, and R3 will be cut out of the circuit and the maximum current will flow. if, however, switches 1, 2 or 3 are operated, a diierent resistance is included in the circuit, and a different current will flow in each Now the resistances R, R2, R3, and the windings of themagnets 6, 7, 7, 8, 8, 9 and 9, are so adjusted and related to one another that when all of `the resistances R, R2 and R3 are cut out of the circuit, that the current is strongenough to actuate all of said magnets, but if the resistances R, R2 and R3 are in the circuit, the current is diminished, so that only the magnets having a large number of windings will attract their armatures. It the switch 1 is alone closed, the magnet 6 is alone operated; if switch 2 is closed,magnets 6, 7 and 7 are alone operated; ifswitch 3 is closed,magnets 6, 7, 7, 8 and 8 are operated', and ifswitch 4 is closed, all of the magnets are energized to attract their armatures, as already stated. The same result could, of course, be secured by varying the current in any way, and by having the efliciency of the different electro-magnets varied in any way, as, for example, by having them varying distances from their armatures, or by having them shunted by resistances. l prefer, however, to make use of a varying number of ampere turns for this purpose. If magnet 6 attracts/its armature, andmagnet 7 does not, which we have `seen occurs only when switch No. 1 is closed, themetallic clips 15 and 15 at the iirst semaphore station come in contact with one another, and these clips are respectively connected to a local circuit m, so as to close the same. If, however, the current is a little stronger, caused by closing switch No. 2, instead of switch No.
' immediate disaster.
1, themagnets 6 and 7 of station I, both attract their armatures, and the local circuit m is not closed. The local circuit m2, at station` II, is, however, closed under' these circumstances, becausemagnet 7 attracts its armature, while magnet 8 does not.
This is because 7 and 7 always worl; together, being of similar strength, but magnet 8 is weaker thanmagnet 7. In this way a local circuit at station No. II is closed by the closure of switch No. 2 at the despatchers station A. In like manner the local circuits m3 and m4 of stations III and IV are closed by the movement ofswitches 3 and 4 at the despatchers station. I have, therefore, secured the closure of any selected circuit of the series of semaphore stations by the manipulation of properly numbered switches at the despatchers station. Theselocal circuits maybe used to start motors orcompressed air devices, or to merely trip the semaphore signals to danger. Many devices are in common use for actuating a semaphore upon the closure of a local circuit, and I do not deem it necessary, or a part of -my invention to describe a particular mechanism for this purpose, It is evident that the local circuit which trips the semaphore is closed only as long as the line current is passing, so that any local batteries in the line circuits m, m2, m3 and m4 are not exhausted, provided batteries are used. The above system of control enables the setting of any desired signal along the line.
I will now described the checking, return signaling o r notification device by which any failure, defect, leakage, open circuiting or short circuiting, exhaustion of batteries, or any 'other cause whatever, will be properly noticedat the despatchers station, so that he may take proper 'steps to have the mechanism repaired, and Ialso to prevent any For this purpose line L2 entirely separate from the line L is untilized.` The esse'ntial characteristic of the line L2 is that it is capable of being placed in a circuit with a source of current, and with current varying devices at each oneof the semaphore stations;
r2, r3. and r4,
resistances are cutout so that the lineis practically continuous from end to end.- All of the resistances r',A r2, @and r4, .are different from lone another, so thatwhen anyswitch `17 isfopened, the' line resistance becomes a The current varying devices illustrated vcomprise resistances r', vT
`each of whichis capable of being bridged or cut outby a switch 17. In the. normal condition of the line L2,all ofthese semaphore station side by side, and each having a different .number of ampere turns, and embodying the principles of my invention, may be very conveniently used. Each of these magnets o, o2, etc., are generally similar to themagnets 6, 7, 7, S, ete., already described. Each has an armature 19, with metallic clips 20, 20', generally similar to theclips 15, 15', of thedevices 6, 7, etc., already described. The clips 20 and 20 of adjacent armatures form the terminals of local circuits, including lamps 21. It is evident that when any two adjacent magnets are both energized, that the circuit of the corresponding lamp 21 is not closed, but if only one of two adjacent magnets is energized, then the circuit of one of the signal lamps 21 will be completed, and
and o5, disposed in a row,
the lamp lighted. In practice it is best to i have the ilirst magnet o of few ampere turns; the second o2 of more ampere turns; the third, of a still larger number, etc. The resistances r', r2, r3 and r4, are progressively greater than'one another; for example, fr may be 500 ohms; r2, 1000 ohms, r3, 1500 ohms g and r4, 2000'ohms. The purpose of having the returnsignaling currents in the lin'e L2 variedin a diminishing ratio for the progressive stations, While the transmitting current in the line L varies in an increasing ratio for the progressive stations, will be later more particularly set forth. The arrangement is made in order to avoid any combination of circumstances producing a false signal and'false return at the same time.
When all of the switches 17 are closed as shown, the current is great enough to energize all of the magnets o', o2, o3, o4 and o5, which all attract' their armatures, so that nonecf the local circuits containing lamps 21, is closed, and no lamp is displayed. If,
however, switch 17, at station No. I is opened, the current, is cut down to a certain extent,
and the adjustment is such that the reduced.
current is just sufficient to energize magnet ,02, but not-suflicient to energize magnet o.
he armature of magnet o2 accordingly is drawn upward to close the circuit of the first signal lamp ,21. Similarly, if switchv 17 of stationl No, II is opened, :the current is cut down still more, so that it is just strong enough to energize magnet o3, but not magnets o and oz. 'Underthese circumstances, i the second signallamp 21w1ll be displayed.A
Inthis way a signal lanip is displayed in.
every case tocorrespond with the particular Aat which a switch 17 is opened. l I
The switches 17 ,i'or any equivalentcurrent i varyingv deviceused in lieu thereof, are' preferably actuated by as direct aconnection as possible with a semaphore arm. I have train and another; for example, to. allow a line L2, so as to make this resistance suitabley passenger train to pass a freight, or to sidetrack va freight at any point for any purpose, or to give a special a clear track, or the various other traffic orders which are re quired, and for which'special telegraph oper-v ators yat stations along the line are in ordinary cases provided. The train despatcher at station A, wishing, for example, to talk to a train at semaphore station' III, .closes switch No. 3, and thereby causes a current to flow through the line L-, which is just suflicient to energize the magnet 8', but not the magnet 9, in the manner already described.l
The local circuit m3 of station III is thereby closed, and the semaphore released'. This is the normal operation, butin case of fogs, tangling of the'wires, sticking of the semaphore arm, or any other influences, it might happen that the wrong, or no, semaphore signal was actuated. In order that such a condition might be at'once notified to the despatcher's office, the return signal comes into use. The switch 17 of stationNo. III, mechanically connected ina direct way with the semaphore arm, .is opened, and the resistance r3 of station III is thrown into the to the 4actuation-of the third lamp 21, at the vdespatchers station A. When, therefore,
the despatcher moves switch 16 over on to' the contact of line L2, the return signal is at once given, and he is informed that the reuired semaphore has`been` properly set. nasmuch as the currentfiow for the actuation of thesignals is a continuous one, it is inconceivable that inductionv or capacity, or any cause, except open circuiting of the lines, or short circuiting or leakage, would have any effect on the signals. I will now show that either of these conditions is at once indicated to the despatchers oilice. Supposing the line L was interrupted by the breakage of the wires, or any cause. Under these clrcumstances, no current would flow through ainmeter 18 when the actuating switches were closed. This would show conclusively that theline was broken. Similarly, if the line L2 was broken, the same ammeter would indicate vno current when the switches were closed for the. return signal. This would'show conclusively that the line L2 was broken.- The third conceivable con dition is that line L2 might be grounded at the same point of its length, either completely by restingon th`e ground, or partly through defective insulators, fogs, rains, etc. The effect of leakage would be to dissipate the current so that the semaphore would be displayed at an earlier station than would be the casel otherwise. But the return signal over the line L2 would at once show the fact that the wrong semaphore had been displayed. Even conceiving that leakage or improper conditions occurred simultaneously in both lines L and L2, it is evident that checking or provingvsignals received by the despatcher.
I regard this as an exceedingly important feature of the invention, and it is the purpose for which the resistances r, 12, T3, etc., are made increasing for theprogressive semaphore stations, instead of diminishing, in their value. line conditions which can occur to influence the apparatus. By tripping the semaphores one after "the other throughout the series,A
and noting the display lamps 21, it is, of course, possible for the despatcher to test out his complete system atany moment, and in practice he will, of course, make this test from time to time as found necessary. Should any defects be found, they are at once remedied.
Semaphore signals after having been tri ped to danger are returned to safety, eitlier by the officers of the train which is stopped thereby, or by any special c1rcuit (not shown), which may operate motors or any required device, for the urpose. The despatchers station A is aways capable of being putin telegraphic or telephonlc communication with any semaphore station through the line L?, which is continuous or uninterru ted throughout the line in its normal condition. I have indicated telephone andtelegraph stations 23, at the des atchers station, and at the various semap ore stations, which may be connected into a common circuit when desired by switches 24. In
this way the oflicers of any train receive their instructions from the despatchers office as soon as the train has been stopped by the display of the semaphore. They may then re-position the semaphore to safety and pro-- The above are all the tionaly"-displayed by the manipulation 'of the switches at the despatchers station, but the system also gives'a prompt' indication of the display of any sema'hore by an accidental cause. For ',examp e, if. the mechanism 'shoirld lbecome broken in storms or high Winds, or any person vtampering :therewith J.Shulds'o close or establish electrical circuits vas to 'release any particular semaphore, this 'fact 'r'vill be promptly signale'din thel line L2 lso as 'too'p'erate the recording deviceo, `02, o, 04, o5, at the despatchers station. In order that the apparatus maybe constantly incondition to 4receive repeating signals of this sort, the switch 1'6 may be left on the contact of the line Wire L2 in its normal state.
iWhat l claim, is
1. ln a signal system, a line having-a plural'ity of signals selectively operatedby dif- 'ierent strengths of current, means for transmitting 'currents oi varying strength to the line, and means for automatically sending back a current of varying strength vto send a repeat or checking signal back to the transmittlng station.
2. lna'si'gnal system, a line having'a plural-ity of signals selectivelyoperated by "different'strengths of current, means for transmitting currents of varying strength to the line, a second line having devicesy therein at each signal -ior sending currents oi varying 'strengths back tothe'transmitting station, fand indicating means at the transmitting station in saidsecond iline, whereby the kparticular -signal displayed is indicated at the transmitting station.
" in 'a signal system a line having signals 'eachwith a plurality of separate contacts se- -`lectively closed by different strengths of current, means for .transmitting currents Tof varying intensity over said line to act'uatel anyv selected si nal, 'and means operated by the signal 'dispay'ed for repeating orchecking the action thereof at .the trasmittingstation.
'4. I'n-a signal system, a line having signals selectively' yoperated by different' strengths of current, means fortransmitting currents of varymglntensity over said line to Vactu'ate any selected signal, a s'ece'nd lme,and means at thev signal actuated fortransmitting a .cur-
. yrent of varying strength overk said second line to che'ck'or'r'epeat the actuation at thetrans-V mitting Station...
.5; in a Si nel System@ une raving'. Signals l"s'electively 'perat'ed'by different strengths of current, means l.for transmitting currents of 'varying intensity over said linejto actuate any, selected signal, and means at the signal. actuated forcausing a currentof "predetersta-tien.4 l,
V6. Ina signal system/a line having si na'ls mined l'strength to io'W at the transmitting selectively operated by different s trengt s 'of' current, means for transmitting'currents 'f varyingintensity over said lineto'actuate anyselected'signal,andimeans at the 'signal mined strength to 'lo'W at the transmitting Y station, the remote -signals being'f'actuatedby -currents 'ofvarying intensity to the transmitting station, depending on the signal actuated.
` 8. ln' a signal system, a line having s i 'nals selectively operated by diiierent strengt s'of current, means' for transmitting currentsof v varying A'intensity oversaid lineto actua'te any select 'ed signal,and means for returning currents of varying l'intensity to the transmitting station, Y depending on the signal actuated, theorder of the stations With resp'ct to 'thecurrent increase being reversed for the return or repeat signals;
9. ln a signal system, a line havingsign'als selectively operated by "dierent strengths of current, a second line having recording signals at the transmitting station Vwhich are selectively actuated by `diiierent 'strengths Vcf current, means at the transmitting station 'for sending currents of any required strength 'over the rst line, and means 'at the signals lfor sending return currents of predetermined strength diiierent for leach station, over the said 'second li'ne.
10.1111 a signal system, two lines, 'si als in one ci said lines adapted t0 be selectively operated by currents of derent strengths, means in the second lin'e for changing the resistance thereof to different values depending 'on the signalac'tuated", recording devices 'at the transmitting station in said secondI line,
and means 'at the transmitting station for 11. In a signal system, a pair of line Wires rality of magnetic signaling devices selectively actuated'by d iiie'rent current strengths, 'means for transmltt'mg currents of v'aryin Vstrengths 'over said line, and means ,operate by the'actuation-ofany particular device for transmitting a 4current ofy redeteiimiiied strengththrough the'second line, the ldinerent devices transmitting currents of 'diler- Jent. strengths, and recording means at the ,transmittlng'station connecting either line with a source of lcurv'one .of vvhichlis in a series circuitlvvith a plu# 'i rit 12. In a signal system, a despatchers station and a plurality of semaphore signals, a pair of line wires traversing' all of the semaphore stations, means at each semaphore sta- A tion selectively actuated by currents of pre- I magnets at each semaphore station each hav- -ing a diiierent number of .turns, a line including all of said magnets 1n a series circuit,
- a second line including a plurality of resistances of dierent values'at the respective stations 'and means operated by the magnets at the different stations for cutting the re-4v sistances at the corresponding station into the circuit ofthe second line Wire.
14. In a signal system, a despatchers station and a plurality of semaphore stations, a pair of line Wires, means at the des atchers station for transmitting currents o varying strengths over one of said line wires, and means at the despatchers stationfor indicating currents o varying 'strength in the other linel wire, and means at each semaphore actuated by a current f predetermined strength in the lirst line wire for causing a current of redetermined strength to How in the second 'ne wire.
15. 'In a si nal system, a despatchers station, and a p urality of semaphore stations, means at the despatchers station for transmitting currents of varying strength tothe various semaphore stations, thestrength of current being eater in proportion to the remoteness oft e station, and means at each semaphore station for causing av current of predetermined strength to low' at the despatchers station, thestrength of said last named current being less in proportion to the remoteness of the semaphore station.
16. In 'a signal system, a despatchers station having a dynamo of 'comparatively high voltage thereat, a plurality of semaphore stations, a pair of line Wires terminating at the despatcherstation one of said line Wires including a magnet at each semaphore station adapted to be selectively-energized to attract its armature by currents of different strength therein and the other wire having resistances adapted to be cut into the line at any station .by the actuation of the magnet thereat, and
means at the despatchers station for connectmg the dynamo to either line wire.
17. In a slgnalsystem, a despatchers station having a source of current thereat, a
lurality of semaphore'stations, a `pair of ine Wires terminating at the des atchers station one of said l1ne wires inc uding a magnet at each semaphore station adapted to be selectively energized to attract its esmas armature by currents of different strength therein and the other wire having resistances adapted to becut into the line at any station -by the actuation of the magnet thereat, and
means at the despatchers station for connecting the source of current `to either line wire. f
18. In a signal system, a despatchers station and a plurality of sema hore stations, a pair otline wires one inclu "ng a magnet at each station, and the other including a resistance 'at each station normally short circuited, and means whereby a telegraph set may be connected to said last-named line at the despatchers station and at any semaphore station for establishing telegraphic communication therethrough.
19. In a 'si nal system, a despatchers station and a p urality of semaphore stations, a pair of line wires one including a magnet at each station, and the other in'cluding a resistance at each station normally short cir-' lnets each having a different number of mag- K net turns, armatures therefor, clips fixed to said armatures, said clips overlapplng 1n a continuous series and normally outof con-` tact, whereby two adjacent clips are electrically connected by the energlzation of one predetermined magnet of the pair corresponding to said clips.
21. In a signal system, a pluralitybf magnets, polar extensions therefrom each bent aro nd in proximity to the other pole of the ma net, an armature on each extension, a
chp fixed to each armature, said clips overlapping in arcontinuous series, whereby any two clips may be brought into electrical contact by the energization of one of a pair of adjacent ma ets.
22. In a signal system, a plurality of magnets each having 'a polar extension bent around in proximity to the other pole, an armature pivoted to the polar extenslon, a pair of chps on each armature, said cli s overlappi in a continuous series for .all t e magnets, t e arrangement of clips on each armature being similar for all the magnets throughout the series,r whereby any. pair of clips may be exclusively brought into electrlcal contact by the exclusive energlzatlon of all the magnets to one side of the point or division produced by said clips.
23. In a signal system, a pluralit of magnets each adapted to be operated y a cur.- rent of predetermined strength different from the rest, armatures therefor'and clips on said armatures, said clips overlapping in a continuous series, whereby any desired cli may be exclusively -brought into contact y the passage of current of redetermined tal'yor intentionallybyatransmittedCurrent strength in the circuit of the e eotromagnets. from the despatohers station. 10
24. In a signal system, a despatchers In witness whereof I subscribe my sigsta-ton, a plurality of signals at spaced stanature, in the presence of two witnesses.
tions along the road, means whereby a cur- JULIEN A. GEHRUNG.
rent of different strength for each signal is Witnesses:
caused to How at the despatohers station WALDO M.CHA1 1N,
when each signal s'displayed either acoiden- MAY BIRD.