US552316A

US552316A - Electrical railway signaling system

Info

Publication number: US552316A
Authority: US
Publication date: 1895-12-31
Anticipated expiration: 1912-12-31

Description

(No Model.) 3 Sheets-Sheet 1.

T. B. DIXON. ELECTRICAL RAILWAY SIGNALING SYSTEM.

Patented Dec. 31, 1895.

Lr 1V I wfiessw (No Model.) 3 Sheets-Sheet 2.

T. B. DIXON. ELEGTRIGAL RAILWAY SIGNALING SYSTEM.

Patented Dec. 31, 1895.

W Zfnessea AN DREW BYGRAHAM. PNOTO-UTHOYWASMI NGTDN. D Cv (No Modei. s Sheets-Sheet 3.

T. B. DIXON.

ELECTRICAL RAILWAY SIGNALING SYSTEM. No. 552,316. PatentedDec. 31, 1895.

' UNTTED STATES PATENT OFFICE,

THOMAS BULLITT DIXON, OF HENDERSON, KENT IOKY.

ELECTRICAL RAILWAY SIGNALING SYSTEM.

SPECIFICATION forming part of Letters Patent No. 552,316, dated December 31, 1895. Application filed July 10, 1894. Serial No. 517,137. (No model.)

T0 at whom it may concern.-

Be itknown that LTHoMAs BULLITT DIXON, a citizen of the United States, residing at Henderson,-in the county of Henderson and State of Kenutcky, have invented certain new and useful Improvements in Electrical Railway Signaling Systems and I do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

My invention relates to electrical railway signaling systems, and particularly to automatic signaling systems; and my invention consists in the novel combinations and arrangements of circuits for accomplishing the results hereinafter specified.

In an application for Letters Patent filed October 5, 1893, Serial No. 487,209,1have described and illustrated an electrical railway signaling system for both single and multiple track railways, in which the track-rails of each block form conductors for circuits controlling the signals of that block, the two lines of rails constituting each block being insulated from each other. In another application for Letters Patent filed March 13, 1894, Serial No. 503,478, which is a division of the application first mentioned, I have described and illustrated certain modifications of the circuits described in the first application, which modifications are particularly intended to adapt the system for use on blocks of great length or where the track-insulation is poor, and the loss due to leakage of current correspondingly great. In the circuits of both of said applications the track-circuits are normally-closed circuits.

In the system of railway signaling shown and described in the present application, which is a further modification and development of the system of railway signaling described in the above-mentioned applications,

the track-circuits are normally-open circuits, current passing through them only when a train is entering or is about to enter the block to which such circuits belong. In this manner there is no loss of current by leakage when a block is not occupied, and therefore longer blocks may be used and fewer batteries are required, while it is not so important as in a closed-circuit system that the track-insulation shall be nearly perfect.

The objects of my invention are, first, to provide a system of railway signaling in which the signals of each block shall be controlled by normally-open track-circuits; sec- 0nd, to provide circuits for so operating these signals that the safety factor may be as high as possible; third, to arrange the circuits to be operated either automatically or by hand; fourth, to make the number and length of the circuits as small as possible, and, fifth, to make the operation of the circuits simple and to make the circuits not liable to derangement. These objects are attained in the system of railway signaling herein described, and illustrated in the drawings which accompany and form a part of this application, in which the same reference letters and numerals indicate the same or corresponding parts, and in which Figure 1 shows the arrangement of circuits for operating one block of one track of a double-track railway. Fig. 2 is a similar view showing the arrangement of circuits for very long blocks or blocks where the track-insulation is poor, the track-circuit being divided into two or more parts. Fig. 3 shows the arrangements of circuits for one block of a singlertrack railway, there being at one of the signal-stations a siding and Fig. 4is a similar view showing the arrangement of circuits on a single-track road for long blocks or blocks where the track-insulation is poor.

In the system herein described, as in the systems described in the above-mentioned applications, Serial Nos. 487,209 and 503,478, the signals controlling traffic are understood to be normally at danger, and are understood to be set to safety by the passage of electric current through the coils of electromagnets controlling the signals.

In the drawings the signals are represented by conventional illustrations of magnets which may be considered to be the controllingmagnets of the signals.

Referring first to Fig. 1, A and B are signal-stations, at the ends of a block A B on a railway-track over which traffic governed by the signals of the system proceeds in but one direction-viz, from A to B.

S is a signal at A controlling the entrance of trains to block A B.

R, R, R and R are circuit-controllers at the ends A and B of the block A B, respectively, and control the circuits of the block.

R and B may be termed line-circuit relays and R and R track or signal-circuit relays.

The portion of the railway-track shown in Fig. 1 is divided into

sections

1, 1, 2, and 2, all insulated from each other, the two paral lel lines of rails constituting the track being likewise insulated from each other.

1 and 2 are short track-sections,which,with the batteries and circuits connected thereto, perform the functions of track-instruments. Track-section l. operates the signals of block A B, but properly should be considered as included within the limits of the block immediately preceding block A B, of which tracksection 1 is the principal track-section, corresponding to track-section 2 of block A B.

2 and 2 together constitute the block A B, 2 being the main track-section of the block.

3 is a local battery at station A, the poles of which are connected to the rails at one end of track-section 1. To the rails at the other end of track-section 1 are connected

conductors

5 and 5 leading to the magnet of relay R. The circuit of battery 3 being always complete, the armature of relay R is normally up; but when acar enters track-section 1 battery 3 is short-circuitcd through the wheels and axles of the ear, and the armature of re lay R falls.

(5 is a line-battery at station A, one pole of which is connected to earth at T, while the other pole is connected by a conductor 7 to the lower second contact-point of relay R, from the corresponding armature contactpoint of which relay a line conductor 8 leads to the magnet of signalcontrolling relay R and thence to earth at T This line-circuit will be completed, therefore, when a car 011 track-section 1 causes the armature of relay R to fall, and when completed will energize the magnet of relay R and cause the ar1nature thereof to rise.

9 is a signal-circuit battery at station B, one pole of which is connected by a conductor 10 with the left-hand rail of track-section 2, while the other pole is connected bya e011- ductor 11 with the armature of signal-relay R The upper contact-point of relay R is connected by a conductor 12 passing through the upper first armature-contact of line-relay R, which contact is closed. when no cars are on track-section 2, with the right-hand rail of track-section 2. At the other end of the block, signal S is connected by conductors 13 and 1st to the rails of track-section 2. lVhen, therefore, the armature of signal-relay R is raised, the circuit of battery 9 is completed, provided no cars are on track-section 2, and current passes through the rails of track-section 2 and through signal S, setting that signal to safety.

The operation of the circuits of Fig. 1 is as follows: Supposing a train to enter track-section 1 from track-section 1, battery 3 will be short-circuited through the wheels and axles of the train, the armature of line-relay :1 will fall, thereby completing the line-circuit of battery 6, causing the armature of signal-relay R at B to rise, thereby completing the circuit of signalbattery 9, provided the armature of line-relay R is up, and so setting signal S to safety, provided no train is already 011 track-section 2 to short-circuit the signal- 'circuit in that section. Signal S having gone to safety, the train may pass on into tracksection 2. \Vhen the first car enters tracksection 2 the circuit of battery 9 is short-circuited, and signal S goes to danger. \Vhen the last car of the train passes oil from tracksection 1 the armature of relay R rises and the armature of relay R falls, thus again breaking the circuit of battery 9. The block AB is still closed to trains on track-section 1, however, for supposing a train to enter track-section 1 while the first train is on tracksection 2, although the armature of relay R will fall and the armature of relay lit will rise, the signal-circuit of battery 9, though completed, will be short-eircuited through the wheels of the train on track-section 2, so that no current can reach signal S, and the signal will remain at danger. \Vhen the first car of the train on traclesection 2 enters track-seetion 2, signal S will be set to safety by the fall of the armature of relay R and the operation of circuits in the block beyond B corresponding to the circuits of block A B, and the train may pass on out of the block A B; but even after the last car of the train has passed off from track-section 2 onto track-section 2 it is still impossible for the train on traclesec' tion 1 to set to safety signal S, since now, although the armatures of relays R and B may be up, the circuit of battery 9 is broken. at the upper first contact of relay R", the armature of which is down. Until the last car of the first train has passed out of track-section 2, therefore, it is impossible for a train at A to enter block A B. It will be observed that current passes through the track-circuit only during the brief time while a train is upon the track-section 1. The amount of batterypower consumed is therefore small, and some leakage in. the track-circuit may be permitted without serious loss. It is possible, therefore, to use current of higher potential in the trackcircuit than is advisable in. normally-closed track-circuits, and for this reason longer blocks maybe operated than with a normallyclosed track-circuit without dividing the track-circuit. For the same reason, it is not necessary to have such perfect t1'aekinsulation. For very long blocks, or for blocks where the track-insulation is poor, it is neces sary or advisable to divide the track-circuit into two or more parts, and the method of doing this is shown in Fig. 2, which is a View similar to Fig. 1, showing one block of a track ITO over which traffic proceeds in but one direction, A and B being the signal-stations at the ends of the block. The circuits at A and at B are the same as at A and B of Fig. 1, as is the line-circuit of the block. The track between stations A and B is divided into two sections, and 16, however, the point of division being at a relay-station O. The signalbattery 9 at B is connected to the rails at one end of track-section 15,- the rails at the other en d of the track-section being connected by conductors 17 and 18with the magnet-coils of a relay R The armature and upper contact-point of this relay are connected by other conductors 19 and 20 with a signal-battery 9 and with the rails of track-section 16, to the other end of which is connected the signal S lVhen, therefore, a train at A causes the completion of the line-circuit of the block and raises the armature of line-relay R at B, the completion of the circuit of battery 9 causes the armature of relay R to rise, thus completing the circuit of battery 9" through signal S thereby setting that signal to safety; but the moment that the train enters track-section 16 the circuit of battery '9 is short-circuited and signal S returns to danger, and it is thereafter impossible for a train.

be provided with distant or caution signals,

placed at the entrance of the short track-instrument track-sections, which signals will be in the same circuit with the home or danger signals shown in Figs. 1 and 2, and will always indicate the same.

In Figs. 3 and 4, to be now described, the home signals are all provided with distant signals.

Referring nowto Fig. 3, this figure, as above stated, shows the arrangement of circuits and signals for tracks over which traffic governed by signals proceeds in both directions. The figure shows one block of such a track, D and E being signal-stations at the ends of the block. The block D E is divided into three track-

sections

31, 32, and 33, of which 31 and 33 are short sections,which with their local circuits correspond to and perform the functions of track-instruments, and 32 is thesection constituting the main portion=of the block.

and 31 are short track-section track-instru ments belonging to the blocks adjacent to block D E, and 29 and 35 are the main tracksections of these blocks adjacent to D E.

S and S are signals controlling the entrance to block D E at D, of which S is a distant or caution signal and S is a danger or home signal. If desired, the distant signal may be omitted and only the home signal used, as in Figs. 1 and 2. Similarly S and S at E are respectively distant and home signals controlling the entrance to the block which lies beyond E. S and S are signals controlling the entrance of trains to block D E at E, and S and S at D are signals controlling thepassage of trains from block D E to the block which lies beyond D.

36 is a local battery, the poles of which are connected to the rails at one end of tracksection 30. The other end of this track-section is connected by conductors 37 and 38 with the magnet of line-relay R which relay corresponds to relay R of Fig. 1, but operates two independent sets of contact-points all insulated from each other.

39 is the line-battery of block D E, which operates the signal-controlling circuits for trains going in the direction from D to E. One pole of the battery is connected to the ground at T The other is connected to the lower first contact-point of relay R To the first armature contact-point of this relay is connected the line-conductor 40 of the block D E, the other end of which is connected to the second lever contact-point of 'a hand-key K at station E. To the upper second contactpoint of key K is connected a conductor 41 leading to the first armature contact-point of relay R From the upper first contact-point of this relay a conductor 42 extends through the magnet-coils of relay R to ground at T mally its upper contacts are closed, and therefore conductors 40 and 41 are practically continuous during the normal operation of the signals, andthe keyK need notbe mentioned in describing the normal operation of the circuits of block at E. The same is true with respect to the key K, the mate to key K upon the other side of the track at E.

43 is the line-battery of block D E which operates the signal-controlling circuits for trains going in the direction from E to D; One pole is connected to ground at T and the other is connected to the lower first contactpoint of relay R From the upper first contact-point of relay R at stationD, a conductor 44 corresponding to conductor 42 at station E leads through the magnet-coils of relay R to ground at T R R R and R are signal-controllingretrack-section of the block. Thence the circuit passes through the rails to the other end of the block, thence through a conductor 50 to the second upper contact-point of relay R".

This relay corresponds to relay R at station D, and its armature is up when no cars are on traclesection 33. The circuit therefore passes from the second contact of relay B through a conductor 51 to the armature contact-point of si gnal-controllin g relay R the armature of which is normally down, and thence through the lower contact-point of this relay through a conductor 52 and signals S and S which control the entrance of trains at E to block D E, to the upper first contact-point of sidingkey K, thence through a conductor 53 to the left-hand rail of track-section 32, through the rails to station D, thence through a conductor 54 to the upper second contact of relay R which is a relay corresponding to relays R and R, and the armature of which is up when no cars are on track-section 31, and through a conductor 55 to the armature contact-point of signal-controlling relay R the armature of which is normally down, thus completing the circuit. It will be observed that while this track or signal circuit is normally con1- plete through the signals at both ends of the block, there is no battery in the circuit, and consequently the signals are all at danger.

45 and 47 are the signal-batteriesof block D E, the poles of battery 45 being connected by conductors 56 and 57 to the upper contactpoint of relay R and to conductor 49 of the track or signal circuit, and battery 47 is connected by conductors 5S and 59 to the upper contact-point of relay R and to conductor 52 of the track or signal circuit. Signals S and S and battery 46 belong to the block beyond E, and signals S' and S and battery 48 belong to the block beyond D.

S and S are signals controlling the movement of trains on the siding at E, are not regarded by trains upon the main track, and are controlled by the keys K and K above mentioned. The circuits and the method of operation of signal S only need be described, as what is true of one signal is likewise true of the other. Signal S isconnected by conductors (35 and 66 with the lower first contact-point of key K and with the track .or signal circuit conductor 51. A battery 67 is connected to the lower second contact of key K and to ground at T. \Vhen the key K isdepressed, signals S and S and battery 47 are cut out of the track or signal circuit, the magnet of relay R is cut out of the line-circuit, and siding-signal S and battery '67 are thrown into the track and line circuits respectively. The e'fie'ct of the changes thus made will be discussed when the operation. of the circuits of Fig. 3 is described.

The conductors pertaining to the signals S and S have been shown in dotted lines to distinguish them as conductors which are not required where a siding is not used. Other circuits at the two signal-stations D and E,which have not been mentioned heretofore, belong to the blocks adjacent to D and E, and are mates of circuits of the block D E, which have been fully described.

The operation of the circuits of Fig. 3 is as follows: Supposing a train to be about to enter the block D E at D, when it enters tracksection 30, battery 36 is short-circuited, and the armature of relay R falls, thereby cutting the magnet of relay R out of the line-circuit formed by the line-conductor 40 and the other conductors connected therewith, and placing battery 39 in this line-circuit. If, now, as will be supposed, no cars are on track-section 34 at station E, so that the armature of relay R is up, the current of battery 39 will pass through the lower first contact of relay B and through conductors 40 41, the upper first contact of re lay R conductor 42, and the magnet-coils of relay R", to ground at T through the earth to T at station D, and so back to battery, thereby causing the armature of signal-controlling relay R to rise, cutting signals S and S at station E out of the track or signal circuit, and so making it impossible to set those signals to safety, and placing signal-battery 47 in the track or signal circuit. There being now a source of electric energy in the track or signal circuit, and signals S and S being to the line, since the armature of signal-controlling relay R is dowlnthese signals will be set to safety and the train on track-section 30 is permitted to enter the block D E. When the first car of the train enters track-section 31 it causes the armature of relay R to fall, thereby breaking the track or signal circuit and setting to danger signals S and S and when the last car of the train passes out of the track-section 30 the armature of a relay corresponding to relay R and situated at the signal-station behind D, is raised, and a circuit is thereby completed through signals S and S at station D, so that the train which has just entered the block D E may back out again without disregarding signals. The circuits through the operation of which signals S and S are thus set to safety are similar to circuits which set to safety signals S and S when the train passes out of the block D E, and the operation of which will be hereinafter described, so that no present description of the operation of the circuits controlling signals S and S is required. When the armature of relay R rises, owing to the passage of the train off from track-section 30, the line-battery 89 is cut out of the line-circuit, thus causing the armature of signal-controlling relay R to fall, thereby placing signals S and S in the signal-circuit, but by the same act cutting out of circuit nal-battery 47, the only battery formerly in the signal-circuit, so that signals S and S remain at danger, as likewise do signals S and S after the train has passed ofi from tracksection 31 and the armature of relay R has risen. The rise of the armature of relay R likewise places the magnet of sign.al-controlling relay in the line-circuit, although, owing to the fact that there is now no battery in this circuit, the armature of relay R rcrnains down. When the train enters track section 32, signals S and S will be held to danger, should a second train attempt to enter the block,through the short-circuitin g of the signal-circuit through the wheels on tracksection 32. YVhen the first car of the train enters track-section 33 at station E, the armature of relay R falls, thereby setting to safety signals S and S in the same manner in which the fall of the armature of relay R set to safety signals S and S, so that the train may pass on into track-sections 34 and 35, and into the block beyond E. When the first car of the train enters section 34, the armature of relay R falls, and signals S and S are set to danger. The fall of the armature of relay R likewise completes the circuit of battery 43 through the lower first contact of relay R line-conductors 41 and 40, the first upper contact of relay R (if the armature of that relay be up, as it will be if no cars are on track-section 30,) conductor 44 and the magnet-coils of relay R to ground at T, thence through the earth to T at E, and back to battery. The magnet of relay R is thus energized, and its armature rises. The track or signal circuit of block D E is still broken, however, at relay R, the armature of which is still down at the time when the first car of the train enters track-section 34; but when the last car of the train passes from track-section 33 to track-section 34, the armature of relay R rises, and the track or signal circuit is completed from the positive pole of battery 45 at station D, through

conductors

57 and 49, the right-hand rails of track-section 32, conductor at station E, the second contact of relay R conductor 51, the lower contact of relay R (the armature of relay B being down since the train is on track-section 34 and the armature of relay R is down,) and through conductor 52, signals S and S conductor 53, the left-hand rails of track-section 32, conductor 54 at station D, the second contact of relay R (the armature of which relay is now up since no cars are on track-section 31,) conductor 55, and through the upper contact of relay R back to the negative pole of battery 45. This circuit being thus completed by the rise of the armatures of relays R and R, signals S and S are set to safety, and the train on track-section 34 is free to move backward again into the block D E if it so desired; but if the train moves onward into the block beyond E, then when the last car has passed off from track-section 34 the armature of relay R rises and signals S and S are set to danger. Until the moment when the last car of the trainthe passage of which through the block has thus been described-has passed off from track-section 34, both ends of the block D E have been closed to other trains desiring to enter the block; for when this first train was on tracksection 30 the armature of relay R was up, and signals S and S were out of the signalcircuit, and could not be set to safety to admit a train to the block at E. When the first train was on track-section 31 the arshort-circuited through the wheels of the train, and as the signals at either end of the block are operated by the signal-battery at the opposite end of the block it would then have been impossible for the signals at either end of the block to be set to safety. When the train was on track-section 33 the signalcircuit was broken at relay R and when the train was on track-section 34 the armature of relay R was up, and signals S and S were not in the signal-circuit; but when the last ear of the train has passed off from tracksection 34 the circuits of the block D E are in exactly the condition that they were in before the train entered the track-section 30, and a second train on track-section 30 will now set to safety signals S and S and may proceed on into the block. As has been heretofore stated, the hand-keys K and K, the effect of which up to this time has been neglected, are for controlling the siding-signals S and 8. These signals are observed only by trains already on the siding and about to pass off from it. The rails of the siding are insulated from the rails of the main track. WVhen, therefore, a train passes onto the siding, it leaves the main track entirely clear as soon as the last car has passed onto the siding, and other trains may then pass on over the main track. When a train 011 the siding desires to enter a block of the main track say, for instance, the block D Ean operator depresses the key K. This breaks the connection formerly existing between the line-circuit conductors 40 and 41, and between the signal-

circuit conductors

52 and 51, thus cutting out of circuit signals S and S and making it impossible to set those signals to safety, and placing the special battery 67 in the line-circuit and the special sidingsignal S in the track-circuit. If now no cars are on any of the track-

sections

33, 32, 31 and 30, the line-circuit is complete through battery 67 and the lower second contact of key K, thus energizing the magnet of relay R causing its armature to rise, and thereby placing battery 45 in circuit wit-h signal S, thereby setting the signal to safety. If, however, when the key K is depressed, there is a car on track-section 30, the armature of relay R will be downand the magnet of relay R will not be energized. If a car is on track-section 31, the armature of relay R will be down and the signal or track circuit will be broken at the second contact of this'relay. If a car be on tracksection 32 the track or signal circuit will be shortcircuited through the wheels of such car; and if a car be on track-section 33 the armature of relay R will be down, and the track or signal circuit will be broken at the second contact of this relay, so that in all of these cases the depressing of the key K cannot result in the setting to safety of signal S and the train must remain upon the siding until the block D E and track-section are clear before it can enter the block. If, after the key K is depressed, a train enters track-section 34 with the intention of e11- terin g the block D E, the fact that the depressing of key K throws line conductor 41 out of the lineeircuit and signals S and S out of the signal or track circuit will make it impos sible to set signals S and S to safety, so that the train cannot enter the block D E.

In Fig. 4 is shown the method of relaying the track or signal circuit for single track used where the block is of exceptional length or where the track-insulation is poor. Since the conductor of the line-circuit may usually be insulated quite perfectly from the ground it will ordinarily be unnecessary to use a relay in the line-circuit, which is therefore identical with the line-circuit of Fig. 3.. If for any reason a relay in the line-circuit is necessary, the connections necessary are substantially the same as those used in relaying telegraph-lines.

In the track or signal circuit there may be as many relay-stations as may be desired. In Fig. 4 but one relay-station F is shown. The circuits at the signal-stations D and E are the same as at D and E of Fig. 3, except that there is no siding at E. The track-section constituting the main portion of the block is divided into two

sections

32 and 32", the lefthand rails only of which need be insulated from each other. It is unnecessary to insulate the section of the right-hand rail. There is a battery 75 at the relay-station and two re lays R and R the magnets of which are in the track-circuit, and since normally there is on batteryin the track-circuit, the armatures of these relays are normally down.

\Vhen, owing to the presence of a car on track-section 34, the armature of relay R falls and the armature of relay R' rises the circuit of battery is completed from the positive pole of the battery through the righthand rails of track-section 32 to 7 0, thence through a conductor 7 7 an d through the magnet-coils of relay R to the lowercontact-point of relay R and since the armature of this relay is down, through conductor 78 to the left-hand rail of track section 32, thence through the rails and through conductor 54 to the second contact of relay R and since the armature of this relay is up, through conductor 55 and the upper contact of relay R back to the negative pole of battery 45. The magnet of relay B being thus energized, its armature rises and a circuit is completed from the positive pole of battery through the upper contact of relay R to the left-hand rail of track-section 32 through conductor 52 at station E, through signals S and S, through the lower contact of relay R the armature of this relay being down, through conductor 51, the second armature-contact of relay R the armature of which is up, and through conductor 50 and the right-hand rail of track-section 32" to 76, and so back to the negative pole of battery 75.

Signals S and S are operated by the circuits of Fig. 4 in the same manner that signals S and S are operated by the circuits of Fig. 3. The same is likewise true of signals S and S The further description of the circuits of Fig. 4 and of their operation is therefore unnecessary.

It is obvious that the signals and circuits of my system may be operated by hand, instead of being operated auton'uttically, if this is desired, hand-keys being substituted for the line-circuit relays.

Having thus completely described. my invention, what I claim, and desire to secure by Letters Patent, is

i. In an electrical railway signaling system, the combination, with an insulated block or section of track, and an electrically controlled signal controlling the entrance of trains to said block at one end thereof, of a battery at the distant end of said block and a signal circuit therefor passin through the rails of said section of track and controlling the signal at the home end of the block, said battery being normally out of said track circuit and a circuit controller operated from the home end of said block, and arranged, when operated, to throw said battery into the signal circuit, substantially as described.

2. In an electrical railway signaling system, the combination, with an insulated block or section of track, and an electrically controlled signal controlling the entrance of trains to said block at one end thereof, of a battery at the distant end of said block and a signal circuit therefor passing through the rails of said section of track and controlling the signal at the home end of the block, said battery being normally out of said track circuit, a circuit controller arranged, when operated, to throw said battery into the signal. circuit, a second circuit controlling said circuit controller, and means operated by a train at the home end of said block for controlling said second circuit, substantially as described.

3. In an electrical railway signaling system the combination, with an insulated block or section of track, and an electrically controlled signal controlling the entrance of trains to said section of track, of a battery at the distant end of said block and a signal circuit therefor passing through the rails of said block and controlling the signal at the home end of the block, said battery being normally out of said track circuit, a relay, likewise at the distant end of said section of track, and adapted to throw said battery into and out of saidsignal controlling circuit, and a second circuit for controlling said relay provided with means, operated from the entrance of said section of track, for controlling the said circuit, said circuit being adapted to control the action of said relay, substantially as described.

4. In an electrical railway signaling system,

the combination, with a block or section of I track having a main insulated track section, a short insulated track section at the entrance to said block, and an electrically controlled signal controlling the entrance of trains to said block or section of track, of a battery at the distant end of said block and a signal circuit therefor passing through the rails of said block and controlling the signal at the home end of the block, said battery being normally out of said track circuit, a relay adapted to throw said battery into and out of said signal circuit, a second circuit controlling the action of said signal circuit relay, a relay controlling said second circuit, and a local circuit and battery for operating said second relay, connected to the rails of said short insulated track section, and operated by the presence of cars thereon, substantially as described.

5. In an electrical railway signaling system, the combination, with two or more insulated blocks or sections of track, and an electrically controlled signal for each block controlling the entrance of trains thereto, of a battery at the distant end of each block and a signal circuit therefor passing through the rails of said block and controlling the signal at the home end of the block, said battery being normally out of said track circuit, a circuit controller for each block operated from the home end of the block and arranged, when operated, to throw the said battery of the block into the signal circuit,-and a circuit controller for each block operated from the entrance of that block, and controlling the signal circuit of the preceding block, and arranged to break said signal circuit when a train is entering the block to which said circuit controller belongs, substantially as described. v

6. In an electrical railway signaling system, the combination, with two insulated blocks or sections of track and an electrically controlled signal for each block, controlling the entrance of trains thereto, of a battery at the distant end of each block and a signal circuit therefor passing through the rails of said block and controlling the signal at the home end of the block, said battery being normally out of said track circuit, a relay for each signal circuit battery adapted to throw said battery into and out of said signal circuit, a second circuit for each block controlling the action of the signal circuit relay of that block, a circuit controlling device for each block controlling the said second circuit of that block, and means operated by the said last named circuit controlling device of the second block for breaking the signal circuit of the first block when the signal battery of said second block is in its signal circuit, substantially as described.

7. In an electrical railway signaling system, the combination, with two insulated blocks or sections of track, and an electrically controlled signal controlling the entrance of trains thereto, of a battery at the distant end of each block and a signal circuit therefor passing through the rails of said block and controlling the signal at the home end of the block, said battery being normally out of said track circuit, a relay for each signal circuit adapted to throw said battery into and .out of said signal circuit, a second circuit for each block, controlling the signal circuit relay of that block, a relay controlling the said second circuit of each block, a local circuit and battery adapted to operate the said relay controlling said second circuit, said local circuit being connected to the rails of a short insulated track section at the entrance of the block and adapted to be operated by the presence of cars on said insulated track section, and means operated by the relay which controls the second circuit of the second block, for breaking the signal circuit of the first block when the signal battery of the second block is in the signal circuit of that block, substantially as described.

8. In an electrical railway signaling system, the combination, with an insulated block or section of track and electrically controlled signals controlling the entrance of trains to said block at the ends thereof, a signal circuit conductor extending through the rails of said block, signal batteries at the ends of the block for operating said signals, and a signal circuit controller or relay at each end of the block adapted, when operated, to connect either the signal or the signal battery at itsend of the block to said signal circuit conductor, of a line circuit conductor extending through the block, a line circuit battery at each end of the block, and a line circuit controller at each end of the block adapted when operated to place either the signal circuit relay or the line battery at its end of the block in circuit with the line conductor of the block, substantially as described.

9. In an electrical railway signaling system, the combination, with an insulated block or section of track and electrically controlled signals controlling the entrance of trains to said block at the ends thereof, a signal circuit conductor extending through the rails of said block, signal batteries at the ends of the block for operating said signals, and a signal circuit controller or relay at each end of the block adapted, when operated, to connect either the signal or the signal battery at its end of the block with said signal circuit conductor, of a line circuit conductor extending through the block, a line circuit battery at each end of the block, a line circuit controller or relay at each end of the block adapted when operated to place either the signal circuit relay or the line circuit battery at its end of the block in circuit with said line conductor, short insulated track sections at the ends of the block, and local circuits and batteries controlling said line circuit relays, each of said local circuits being connected to the rails of a short insulated track section at its end of the IIO block and adapted to be operated by the presence of cars upon said track section, substantially as described.

10. In an electrical railway signaling system the combination, with an insulated block or section of track and electrically controlled signals controlling the entrance of trains to said block at the ends thereof, a signal circuit extending through the rails of said block and normally connected to said signals, signal batteries at the ends of the block for operating said signals, and normally out of circuit with said signal circuit, and a circuit controller or relay at each end of the block adapted, when operated, to place the signal at its end of the block out of circuit with the signal circuit and to place the signal circuit battery at its end of the block in circuit with the signal circuit, of a line circuit conductor extending through the block, a line circuit battery at each end of the block, and a line circuit controller at each end of the block adapted when operated to place either the signal circuit relay or the line battery at its end of the block in circuit with the line conductor of the block, substantially as described.

11. In an electrical railway signaling system, the combination, with an insulated block or section of track, and electricallycontrolled signals controlling the entrance of trains to said block at the ends thereof, a signal circuit extending through the rails of said block, signal batteries at the ends of the block for operating said signals, and a signal circuit controller or relay at each end of the block adapted, when operated, to connect either the sig nal or the signal battery at its end of the block with said signal circuit, of a line circuit conductor extending through the block and normally connected to the said signal circuit relays, a line circuit battery at each end of the block normally out of circuit with said line conductor, and a line circuit'controller at each end of the block adapted when operated to place the signal circuit relay at its end of the block out of circuit with said line conductor and to place the line circuit battery at its end of the block in circuit with the line conductor, substantially as described.

In testimony whereof I afiix my signature in presence of two witnesses.

THOMAS BULLITT DIXON.

Vitnesses:

JAooB NEWMAN, JAMES A. C. JOHNSON.