US1345816A - Automatic train controlling and stopping mechanism - Google Patents

Description

F. C, WILLIAMS. AUTOMATIC TRAIN CONTROLLING AND STOPPING MECHANISM APPLICATION FILED APR. I9. 1917.

Patentefi July 6, 1920.

3 SHEETS-SHEET l.

INVENTOR Ema/1" 6. Fw /fem).

WITNESS A TTORNEYS F. C. WILLIAMS.

AUTOMATIC TRAIN CONTROLLING AND STOPPING MECHANISM.

APPLICATION FILED APR. 19. I917.

Patented July 6, 1920.

3 SHEETSSHEET 2.

INVENTOR W1 WITNESS ATTORNEYS APPLICATION FILED APR-19,19I7.

Patented July 6, 19%.

3 SHEETS-SHEET 3.

NESS I I ATTQRNEYE;

UNITED STATES PTENT OFFICE.

FBJLLN K C. WILLIAMS, OF PHILADELPHIA, PENNSYLVANIA, ASSIGNOR TO THE SAFETY BLOCK SIGNAL COMPANY, A CORPORATION OF DELAWARE.

AUTOMATIC TRAIN CONTROLLING AND STOPPING MECHANISM.

1,34l5,31ii.

A Application filed April 19,

To (ZZZ whom it may concern:

Be it known that I, FRANK C. l/VILLInMs, a citizen or the United States, and a resident of Philadelphia, in the county of Philadelphia and State of Pennsylvania, have invented certain new and useful Improvements in Automatic Train Controlling and Stopping Mechanisnn'of which the following in a specification.

The objects of this invention are to provide an apparatus for automatically controlling the operation of trains in a block system operated under a short headway providing a mechanism for automatically stopping a train in one block dependent on the condition of the adjacent block it the train is moving above a pre-determined rate of speed but permitting the train to proceed it moving below a pre-determined rate of speed. The present invention relates to improvements in the invention disclosed and claimed in my copending applications, Serial No. 126,872, and Serial No. 141,355, in which by insulating the propulsion line or third rail a train stopping section is pro vidc-d. This section is adapted to be so controlled by the various trains in the block system to be thrown into or out of eleo trical connection with the main propulsion line dependent on the condition of the blocks oi? the system and thus control the operation of a train stopping mechanism carried by the train being controlled and located in one of the rearward blocks.

By the present invention all insulation of the third rail into sections is avoided and instead thetrain stopping section is formed by providing an independent contacting track section adapted to be automatically controlled by certain block circuits of the system so as to be electrically energized from the main propulsion line or deener- 'zed therefrom in the manner referred to so as to automatically regulate the operation of F the train stopping mechanism from the condition of the blocks of the system.

Further objects of this invention are to provide an improved automatic train stoppin and regulating apparatus incorporating this arrangement and further providing a structure wherein a normally electrically energized element is operative when deenergized to stop the train but is normally maintained energized by a suitable supply of electrical energy either obtained from the Specification of Letters Patent.

Patented July 6, 1920.

1917. Serial No. 163,100.

source of supply carried by the train or i'rom the main propulsion line which operates the train, and means are provided 1n each block for cutting off the normal supply and throwing into connection with the mechanism carried by the train a temporarily operating supply of current which supply is automatically controlled for each block by the condition of the adjacent block in advance of the same. If a train is in the block ahead of a second train, the temporary supply of current to the mechanism for controlling the operation of the second train is shut off and the train will be stopped unless a third source of current supply, which is provided and is arranged to be controlled by a speed responsive device on the train, maintains the stopping mechanism inoperative, the third circuit being closed if the train is moving below a predetermined rate of speed.

Further objects of this invention are to provide in a mechanism of the character indicated, suitably constructed contact shoes so connected in the controlling circuits of the train stopping and regulating mecha nism, as to automatically effect an operation of the apparatus as just indicated; to provide contact elements of the character indicated which may also be used, it de sired, as the means for supplying the propulsion current to the train to operate the same; and to provide an apparatus of this character in which the mechanism operates to prevent the application of the train stopping mechanism even if a break occurs in the main propulsion line but on the other hand to effect the stopping of the train in event of the accidental breaking of the electrical connections in the various controlling circuits.

Further objects of my invention include means whereby the mechanism which acts to operate the automatic control of the train when the same is controlled from the main source of current supply used in running the train, is so constructed as to avoid arcing of the current and furthermore the apparatus forming the subject matter of this invention may be readily adapted for use as a train speed controlling mechanism merely without actually stopping the train.

Referring to the drawings forming a part of this specification, Figure 1 shows diagrammatically one form of apparatus in a position to stop a train in one block of a block system, while Fig. 2 is a similar View showing the position of the apparatus when the train stopping mechanism is being maintained in inoperative position.

matic'view in which the normal supply of current for maintaining the controlling apparatus inoperative is obtained from the main propulsion line'or from a source outside of the train itself, and in which the same contact shoe is used for supplying the main posed in the line 13.

trols an armature 15 adapted to'make or 1 operating current to the train and the current used in controlling the train stopping mechanism. Figs. 4: and5 are views of the same modification as Fig. 3 showing the ap-' paratus in different operative posit-ions;

Referring to Figs. 1 and 2, the tracks 1 are divided by a series of sets of insulation 2 into blocks a, Z) and 0 shown in the drawing. Any form of propulsion line supplying current for operating the train may be used and is shown as the third rail 3. Each block is provided with a train stoppingcontact section a although one section is shown in Fig. 1, located in block a. This section 4:

.is adapted to be engaged by a contacting shoe carried by the train and if supplied with electrical energy to prevent the operation of the train stopping mechanism. Any

suitable mean for controlling the supply of energy to the section 4 dependent on whether or not the section just in advance thereof is clear or not, may be usedand as shown for the purpose of illustration, a relay is'connected by leads 6 and 7 to the rails 1 of the block Z). Each block is supplied through a transformer 3 with current to the rails l of each block, being led thereto by suitable leads 9 and 10. The relay 5 is located at the opposite end of the'block '5 from the transformer 8 so that if a train is in the block Z) the current to therelay 5 is short-circuited and the relay deenergized, as is well understood in the art. One means of controlling the supply of current to the contact-section 4 of each block is by throwing the same into V series with the third rail 3 and controlling this operation from the relay 5. .For this purpose an auxiliary magnet 11 is connected'by one lead 12 to the lead 9 extending from the transformer to the rail. Another lead 13 extends from the magnet 11 to the other lead 10 from the transformer and a switch 14 controlledbythe relay 5 is inter- Themagnet 11 conbreak the connection with the points 16 and 17, connected to the section 1 and third rail 3, respectively. "F or the purpose of illustration the third rail and train stopping section 4; are shown in the drawings both in plan view and in section in the same figure, and the connection to each shown by use of full and dotted lines as indicated. It will Fig. 3 shows a modified form of apparatus in diagram- -The automatic mechanism for cutting off the supply ofcurrent to the motor 22 and applying the brakes of the train may be of any convenient form and I have illustrated herewith an electro-magnetically controlled valve 30 adapted to control the supply of air under pressure from the tank 31 through pipes 32 and 33 to the cylinder 34 of the train pipe valve 35. The train pipe 36 1s connected through the valve 35 to the switch controlling cylinder 37, in which is located a piston 38 connected by a rod v39 to the switch 23. Suitable exhaust ports 40 in the cylinder 3'? permit the escape of air from the train pipe 36 and the cylinder 37 when the piston 38 has been moved to the extreme end of the cylinder 38. hen the valve '30 is held up the fluidunder pressure holds the train pipe valve 35 closed, and when the valve 30 is permitted to close the pipe 33 is put into communication with the atmosphere through the exhaust 41. The valve 30 is provided with an armature 42 controlled by the electromagnet as s0 that the operation of the same may be electrically controlled as hereinafter described. The train is supplied with a suitable battery a l connected by a lead 45 to the magnet 43 and by a lead 4:6 to the governor controlled contact 457. The contact 47 is controlledby a governor 18 as will be readily understood shoe on each side of the train as the third rail is sometimes located on opposite sides of the track and it may be desirable to also locate the section 4: at certain places 011 either side of the tracln I have shown in Figs. '1 and 2 a form of contact shoe, one being located on each side of the train adapted to engage with the train stopping section a of each block but not to engage the third rail 3. Various forms of shoes might be used in conjunction with the mechanism shown herein and as one means of construction I have shown a contacting shoe in which a stationary portion 55 is secured to the truck bolster 56 and is provided with a purpose which will hereinafter appear, and the section has hinged thereto a section provided with two conductors or contacts 61 and ($2 insulated at 63 and 64 from the rest of the shoe. A curved contact member (35 is adapted to connect the contact 61 with the contact 57 when in the position as shown in Fig. 2. The contact 62 is connected by a lead 66 to the contact 62 of the other shoe and the contact 61 is connected by a lead 67 to the contact 61 of the other shoe, while the contact 57 is connected by a lead 68 to the lead 50 and electromagnet 43. A lead 69 connects the contact 62 with the lead 45 to the electromagnet 43.

The operation of the mechanism illustrated in Figs. 1 and 2 will now be described. Normally the magnet 43 is energized to prevent the opening of the switch 23 and application of the brakes of the train by a source of current supplied from the battery 44 as best shown in Fig. 2 through the lead 58, contact 57 curved finger 65, contact 61, lead 67, contact 61, finger contact 57, leads 68 and 50, magnet 43 and the return lead 45 to the battery 44. This circuit forms the normally operating train circuit for the magnet 43. In this manner it will be seen that the train may be run at any speed dependent on the control of the operator. lVhen, however, one of the arms 60 or 60 of the contact shoes comes in contact with a train stopping section 4, the normal supply of current to the magnet 43 is broken as shown in Fig. 1 by the movement of the finger 65 off the contact 57 onto the insulation 59. The contact 62 at the same time engages the section 4 or train stopping ramp and if the same is thrown into series and supplied with energy from the third rail 3, by reason of the block Z) being clear, then the magnet 43 will be energized by circuit from the ramp 4, contact 62 of one shoe, lead 66, contact 62 of the other shoe, lead 69, magnet 43 and ground lead 70, which as shown extends through the governor 48 to the ground lead 24. This forms a temporarily operating track circuit from the magnet 43. If, however, a train is in the block b, as shown in Fig. 1, the ramp 4 will not be energized and this circuit just described will be open since the contact points 16 and 17 will be broken by reason of the magnet 11 being deenergized through the drop of the switch 14 which in turn has been allowed to drop by reason of the shortcircuiting of the current energizing the relay 5 as is readily understood in the art. It now the governor controlled circuit, described above and carried by the train for energizing the magnet 43, is also broken by reason of the Xcessive rate of speed, the armature 42 will fall and valve 30 will close and effect an application of the brakes and an automatic breaking of the switch 23.

This is arranged to occur if the train is moving at a higher rate of speed than a predetermined low rate, such as five miles an hour, since the contact 47 will be moved away from the contact 49, thus breaking the circuit from the battery 44, lead 46, contacts 47 and 49, and lead 50 to the magnet 43, and return lead 45 to the battery. In this manner it will be seen that the mechanism operates to permit a train to move at a slow rate of speed into a block already occupied by a train, but if the train is being operated beyond a pre-determined rate and the block in advance is occupied, then the train will be automatically stopped.

It will thus be seen that the magnet 43 is normally energized by the train carried battery circuit in the form shown in Figs. 1 and 2 and that when the shoes engage the ramp 4 the normal supply is cut off and a temporary operative track circuit, independent of the governor, energizes the magnet 43 if the block ahead is clear, but if the same is not clear, then the magnet 43 is energized only from the governor controlled circuit and therefore the operation of the train is controlled at this time by the speed of the train alone. Furthermore, it will be noted that the third rail or main propulsion line is not insulated into sections, but instead suitable contact sections 4 insulated from the third rail are located in any convenient position in each block and form the train stopping contact sections in each block.

In the modification shown in Figs. 3 to 5 the magnet for controlling the automatic stopping mechanism is normally energized from the main supply of current and also temporarily energized or not through the stopping section 4 dependent upon the condition of the adjacent block in the same manner as that shown above in connection with Figs. 1 and 2. In Figs. 3 to 5 the battery circuit is only used to energize the con trolling magnet when the train is moving below five miles an hour and the circuits both normal and temporary which obtain their supply from the main line are broken, or when the third rail is broken as shown in Fig. 5. It will thus be seen that the modification of Figs. 3 to 5 differs from the construction shown in Figs. 1 and 2, mainly in that the magnet is energized normally from the main supply of current extraneous of the train rather than from the battery or other source of supply carried by the train itself. Furthermore, in the modification Figs. 3 to 5, a single contacting shoe supplies the current to the main train operating motor as well as the electromagnetically controlled train stopping mechanism.

In Figs. 3 to 5, as in. the other modification, the tracks 1 are divided by a series of sets of insulation 2 into blocks A, B, 0

shown in the drawing. Any form of propulsion current supplying line may be used and the third rail 3 shown in the drawing illustrates one means of supplying current to the train; Each block is provided with a train stopping contact section 4, separated and insulated from the third rail 3. other case the section 4 is adapted to temporarily supply the train with electrical energy it the section itself is thrown into electrical" connection with a source of current supply as by being connected in series to the third rail 3, the connection being controlled by the condition of the block ahead, the construction being such that the section 4 will be energized if the adjacent block is clear but deenergized if the saine is not clear but is occupied by a train. The same.

apparatus for controlling the energization of the section 4 may be used in the modification of Figs. 3 toi5, as described above in connection with Figs. 1 .and 2. The same form of train stopping mechanism may also be used, the train also carrying a source of supply as the battery 44 and the speed responsive device 48. The contacting shoes used in the modification Figs. 3 to 5 are slightly modified from those shown in Figs. 1 and 2 and are adapted to supply the motor 22 with electrical energy through the'lead 75. ,The shoe 76 issecured as before to the bolster 56 on the train and in this case, is adapted to engage the top of the third rail as shown in Fig. 4 and the topot the ramp 4 by reason of a projection 77 on'the movable arms 7 8 of the shoe. A contact 79 is insulated from the projection 77 and is provided with a curved spring finger 80 adapted when the shoe is free to engage the conductor 81 as shownin Fig. 5. Normally, the finger 80 engages an insulated portion 82 on the shoe 76 when the arm '78 engages the third rail 3 as shown in Fig. 4. A lead 85 connects the dependingprojection 77 of the shoe 7 6 with the projection 77 of the shoe 76?, while a lead 86 connects the contact 79 with the contact 79 on the shoe 7 6'. The contact 81 is connected-by a lead 87 to the battery 44, while the contact 81 on the other shoe is connected by a lead 88 to the magnet 43. The lead in this case connects the other side of the magnet 43 with the ground lead 24 through the governor 48. The depending projection 7 7 is connected by a lead 89 to the magnet 43, as shown, and the battery 44 is also connected thereto through the governor controlled switch by the leads 45 and 46, contacts 47, 49 and lead 50, as in the other modification, forming the governor controlled circuit for the magnet 43.

The operation of this form of my invention is as follows: 7

In this modification, the apparatus is normally maintained in the position shown in Fig. 4 wherein it will be seenthat the shoe 78' is engaging the third rail and supplying As in the current through the lead 75, switch 23 to the motor 22, the circuitbeing completed by the ground lead 24. The magnet 43 is energized by a current from the third rail through the shoe 78, projection 77, lead 85, projection 77", lead 89, magnet 43, ground wire 70, to ground lead 24, this circuit forming the normally operatingcircuit for energizing the magnet 43. 7

hen, however, the shoe 7 8 engages the ramp 4, its contact with the third rail is immediately broken as shown in Fig. 3 by reason otthe projection 77 engaging the ramp 4. As in the other modification, the ramp 4 may be energized or not, depending upon whether or not the block 13 is clear. If the block 13 is clear, the current from the third rail 3 is connected in series with the ramp 4 through the automatically controlled relay 11 and armature 15. T he motor 22 will then be supplied with current through the lead and projection 77 from the ramp 4, and the magnet 43 is energized by the same circuit, as that just described in connection with Fig. 4, as the temporarily operating track circuit. This circuit is from the ramp 4, contact 77, lead 85, contact 77 lead 89, magnet 43, lead 70 to ground lead 24. If, however, a train is located in block 13, as shown in Fig. 3, then the armature 15 will drop and the ramp 4 is de'nergized. No current is supplied to the motor 22, nor to the temporarily operating track circuit described tor energizing the magnet 43. Both the normal and temporary circuits are then broken but the train is moving at a rate of speed below, say five miles an hour, the mag- 7 net 43 will still be energized by the governor controlled circuit and the train will be permitted to advance by its momentum. In this case the circuit is from the battery 44 through the lead 46, contacts 47 and 49, lead 50, magnet 43, and return lead 45, as above indicated. It will be apparent that if the contact 47 controlled by the governor 48 breaks the circuit last described, the brakes will be applied and the train stopped.

it will be seen that in the modification of Figs. 3 to 5, the magnet 43 is normally energized from the main line su-pply, instead of by a train carried battery circuit as in Figs. 1 and 2. When one of the shoes engages the stopping section 4, the propulsion current will be immediately cut oii and the magnet 43 will be temporarily energized or not, depending upon the condition of the track circuit through section 4 and formed when a current is passing. through the section '4 in series with the main propulsion line, or when the block ahead isclear. If not clear, the track circuit is broken and then the magnet 43 is energized or not from acircuit controlled by the governor, dependent upon the speed of the train.

In both forms of the invention the mechanism is so arranged that a break in the propulsion line will not of itself effect a stopping of the train.

Fig. 5 illustrates the action of the modification when a break in the third rail 3 occurs as at crossings, switches, and the like. In this position of the apparatus, the valve 43 is energized by battery circuit extending from the battery 44 through the leads 87, contact 81, finger 80, contact 79, lead 86, contact 79, finger 80, contact 81, lead 88, magnet 43, and return lead 45. In the forms shown in Figs. 1 and 2 if any breaks occur in the third rail 3, the same have no effect whatever on the apparatus but it remains in the position shown in Fig. 2, since the shoes 56 and 56 in this form of the invention do not engage the third rail.

Attention is called to the fact that each of the various circuits used to control the valve 30 is a normally closed circuit whereby any defect in a circuit will effect an operation of the train stopping mechanism when that circuit alone is holding up valve 30. In this manner it is evident that the device will operate to stop the train if any of the circuits become accidentally broken rather than permitting the train to proceed as is the case in which an open circuit controls the valve having a tendency to result in collisions which would be otherwise avoided by the use of the normally operating closed circuits of the present invention.

It is evident that this invention also provides an automatic train stopping apparatus which could be readily arranged to oper ate merely to gradually apply the brakes without shutting off the source of power and thus operate as a speed controlling mechanism without stopping the train, if de sired.

The specific arrangement of apparatus described and illustrated herein forms eflicient means for carrying out this invention but it is obvious that various changes in the arrangement of parts and the electrical circuits may be readily made without departing from the scope and spirit of the invention as set forth in the claims hereunto annexed.

Having thus fully described my invention, what I desire to claim and protect by Letters Patent of the United States is:

1. In an apparatus for controlling the operation of trains in a series of blocks, a main propulsion current supplying line, electro-magnetic means for regulating the operation of a train in a block, a normal supply of current therefor and means including a section independent of the main current supplying means for the system operating to temporarily supply energy to said electro-magnetic means dependent upon the presence or absence of a train in an adjacent block.

2. In an apparatus for automatically conply, for cutting oil the normal supply of energy to the train stopping means and temporarily eiiecting the supply of energy thereto controlled by the condition of the track in an adjacent block of the system.

3. In a train stopping device, electro-magnetic means for automatically controlling the operation of a train in a block of a block system, a main propulsion current supplying line, a plurality of circuits adapted to supply electrical energy to said means including a normally operative circuit, a temporarily operative circuit and a governor controlled circuit, said temporarily operative circuit including a section independent of the main propulsion line oi: the system and means automatically operated whereby the electro-magnetic controlling means will operate to stop a train in a block it running higher than a pre-determined speed and there is a train in the block ahead, and to prevent the operation of said controlling means if the train is running under a pre determined speed and the block ahead is occupied, or if the block ahead is clear.

4. In a train stopping and controlling mechanism for automatically regulating the operation of trains in a series of blocks, a main propulsion current supplying line, electro-magnetic means "for stopping a train, a normal, a temporary, and a speed controlled circuit therefor, means for normally closing the normal circuit through the electro-magnetic means, and means located in each block to cut off the normal supply and make or break the temporary supply dependent upon the condition of the block ahead, whereby the mechanism will operate to stop the train it running higher than a predetermined speed and the block ahead is occupied.

5. In a train stopping device clectro-magnetic means for automatically controlling the operation of a train in the block, a main propulsion current supplying line, a plurality of circuits adapted to supply electrical energy to said controlling means including a speed controlled circuit, a normal circuit and a temporary circuit including a section independent of the main propulsion line of the system, means carried by the train for closing said normal circuit, and means controlled by the speed of the train and the condition of the adjacent blocks of the system for controlling the speed controlled and temporary circuits.

6. In an automatic train stopping mechanism, an electro-magnetically controlled stoppingmeohanis m, a main propulsion current supplymg llne, a normally closed 011'- cuit therefor, a temporarily operatnig circuit therefor including a train stopping contact section independent of the main current supplying means controlled by the condition of the block ahead in the system, a speed controlled circuit and means automatically operated to open the normally closed circuit and operative to make the temporary circuit dependent upon the condition ot theadj acent blocks of the system the mechanism operative whereby the train in .a block will be stopped it running at a higher than a predetermined rate of speed and the block ahead is occupied by another train.

7 In an electrically operated mechanism for propelling and controlling trains in a block system, a propulsionline and atrain controlling mechanism including electroma netic means for re ulatin theo aeration of a train in a block, a circuit adapted to supply electrical energy thereto dependent upon the speed of the train, a plurality of other circuits therefor including a normally operating circuit and a temporarily operating circuit, said last-mentioned circuit 7 including a train stopping track section in each block independent of the propulsion line, and means carried by the train and cooperating with said independent track section'located in each block to cut off the normally operating circuit and close the temporarily operating circuit.

8. Ina train stopping device, the combination of a track having a first andsecond insulated block, a mainpropulsion supplying current line and an independent train "stopping contact section located in each block, means to normallyencrgize said train stoppingsection and means to automatically .deenergize said section of the second block' when a train is in the first block.

9. In a train stopping mechanism, the combination of atrack having a firstand second insulated block, a line adapted to sup- "-ply the operating energy for the system, a 7 train stopping'section independent of said line located in each block, means to normally energize said section, means to deenergize said section in the second block when a train is inthe first block means to stop a train attempting to enter the first block when another train is located therein and the train in the second block is runn ng at a higher rate of speed than a pre-determined low rate of speed, and means to permit the train to enter said first block when running below a predetermined rate 7 e0 of speed. V

10. In a train stopping mechanism, the

combination of a track having a first and sec ond insulated block, a third rail adapted to supply current to the system, a train stop plug contacting section independent of the third rail in each block, means to energize said section in the second block when the first block is clear, and deenergize said section when the first block is occupied, and means whereby a de'elnergized train stopping section is inoperative to stop a train located adjacent said section when said train is moving below a pre-determined rate of speed.

11. In a train stopping mechanism, the combination of a track having a plurality of insulated blocks, a third rail for supplying current to the system, a train stopping section independent of the third rail and insulated therefrom, means to energize said section in each block when theblock ahead 'is clear and to deenergize' the same when the "in series therewith, means to throw said section into and out of series with the line dependent upon'thecondition ota block ahead and means carried by the train cooperating with the independent section to open the normal circuit and close the temporarily operative circuit to the electro-magnetic controlling device. g p

13. In a train controlling mechanism, an electro-magnetically operated train stopping mechanism, a main propulsion current supplying line, a train circuit normally energizing the same to hold the same inoperative, a temporarily operative track circuit which is opened or closed dependent'upon the condi-' tion of the block ahead adapted to be automatically energized or deenergized from the main propulsion line of the system, and

-means carried by the train operative to open the normally closed train circuit and close the temporarily operative'traclr circuit to said electro-magnetically controlled stopping mechanism. I

7 let. In an automatic train controlling mechanism for regulating trains in a block system, a main propulsion current supplying line, a normally closed train circuit for energizing an electro-magnetically operated train stopping mechanism, a track circuit adapted to be energized from the main pro pulsion line of the system, means for opening or closing said circuit in one block dependent upon the conditionof the block ahead, aspeed controlled circuiticarried by the train and means adapted to open the normally closed circuit and throw into operative connection the temporarily operative track circuit so that a train in a block will be stopped it running at a rate of speed higher than a predetermined low rate of speed and the block ahead is occupied.

15. In an automatic train controlling mechanism for regulating trains in a block system, a main propulsion current supplying line for the system, an electro-magnetically controlled device for automatically stopping the train, a normally closed circuit therefor, and a temporarily operating circuit therefor controlled by the condition of the adjacent blocks of the system, including an independent contact section adapted to be energized from the main propulsion line of the system, said circuits operative to energize said controlling de vice independently of any breaks in said propulsion line of the system.

16. In an automatic train controlling mechanism, an electro-magnetically operated train stopping device, a speed controlled circuit therefor, a normally operating circuit therefor, a main line for supplying current to the system, a train stopping contacting section independent thereof,

a temporarily operating circuit controlled by the blocks of the system for the train stopping device passing therethrough, and means carried by the train and cooperating with the independent section to open the normally operating circuit of the stopping device and close the temporarily operating circuit therefor so that if the independent section is deenergized and the speed controlled circuit broken the current stopping device will operate to stop the train.

In Witness whereof I have hereunto set my hand this 17th day of April, A. D. 1917.

FRANK C. WILLIAMS.

Images