US797860A

US797860A - Train-control system.

Info

Publication number: US797860A
Application number: US24284405A
Authority: US
Inventors: Charles E Lord
Original assignee: General Electric Co
Current assignee: General Electric Co
Priority date: 1905-01-27
Filing date: 1905-01-27
Publication date: 1905-08-22
Anticipated expiration: 1922-08-22

Description

No. 797,860. 7 PATENTED AUG. 22, 1905. G. E. LORD.

TRAIN CONTROL SYSTEM.

APPLICATION FILED JAN. 27. 1905.

2 SHBETSSHEET 1.

Wimesses IHVQTHTOP.

E I; L Charl es ELord.

W I B WMAW PATENTED AUG. 22, 1905.

G. E. LORD.

TRAIN CONTROL SYSTEM.

APPLICATION FILED JAN. 27. 1905.

2 SHEETS-SHEET 2.

lnvemori Charles E. Lord.

Witnesses.

UNITED STATES PATENT OFFICE.

CHARLES E. LORD, OF CINCINNATI, OHIO, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEWV YORK.

TRAIN-CONTROL SYSTEM.

Specification of Letters Patent.

Patented Aug. 22, 1905.

Application filed January 27, 1905. Serial No. 242,844.

T 0 ail whom, it nury concern:

Be it known that I, CHARLES E. LORD, a citizen of the United States, residing at Cincinnati, county of Hamilton, State of Ohio, have invented certain new and useful Improvements in Train-Control Systems, of which the following is a specification.

My present invention relates to systems of motor control, and especially to systems of control for a plurality of motors mounted upon the several cars of a train.

Oneof the objects of the invention is to simplify the construction and arrangement of parts of a motor-controller of the separately-actuated-contact type in which the contacts operate in automatic progression and to render more positive the operations of the individual contacts.

A further object is to obtain in motor-controllers of the separately actuated contact type, and especially in train-control systems having a plurality of such controllers, an efficient automatic progressive operation through series and parallel of the controller-contacts, while at the same time using a small number of operating parts in the motor-controller and a small number of connections to the master-controller. These objects I accomplish by employing a pneumatically-operated reversingswitch and series-parallel motorcontroller having separate pneumatically-0o erated contacts and means controlled by said contacts for producing an automatic progressive operation of the contacts. The compressed air is supplied through but two pipes to the reversing-switch and contact-operating means in such a manner as to obtain series and parallel connections in forward or reverse direction of rotation of the motors.

The invention also consists of a system of train control in which each of a plurality of cars is equipped with amotor-controller of the separately-actuated contact type with pneumatic actuatingmeans forthe contacts, means such as electrically-operated means independent of the contact-actuating means for maintaining the contacts, and a pneumatic train system for controlling the actuating and maintaining means.

The invention also comprises details of construction and combination of parts of the system, which will be hereinafter explained, and more clearly pointed out in the appended claims.

In the accompanying drawings, which illustrate the preferred embodiment of my invention, Figure 1 is a diagrammatic representation of so much of the equipment of a single car in a system of train control as is necessary to properly illustrate my invention. Fig. 2 represents diagrammatically a train of three cars equipped with my invention. Fig. 3 is a simplified diagram of the control system, the motor-circuits being omitted. Fig. 4 is a sectional view through the double-throw automatic valve controlling the connections to the operating means of resistance-controlling contacts, and Fig. 5 is a section through one of the mechanically-operated valves controlling the automatic progressive operation of the contacts.

Referring now to the drawings, the motor- .controller C consists of a plurality of pneumatically-operated contacts6 to 12, inclusive, controlling the connections of the motors M and M The contact 6 controls the series connections of the motors, the contacts 7 and 8 control the parallel connections, and the remaining contacts 9 to 12, inclusive, control the sections of

resistance

13, 14, and 15 which are inserted in the motor-circuit when said motors are connected in series or in parallel.

Each controller-contact is provided with pneumatic operating means consisting of the piston 16, contained within the cylinder 17. Each of the resistance-controlling contacts is also provided with maintaining means independent of the operating means, being here shown as holding-coil 18. The maintaining or holding coils are preferably connected in series relationship, as shown, in order to reduce the size of the individual coils and permit their operating upon a circuit connected from the supply-main to the return in shunt to the motors. The piston 16 has attached thereto apiston-rod 16, the function of which will be hereinafter described, and also a piston-rod 19, which has a lost-motion connection with the movable contact-arm 20, the latter being adapted to engage the fixed contact 21. Said contact-arm 20 is provided with an extension 22 of magnetic material, insulated from the arm proper, acting as the armature of the holding coils or magnets 18. The coil 18 is not of sufiicient strength to operate the contact-arm 20-that is, to move said arm into engagement with the contact 21 from its open position-but is sufficiently strong to maintain the contacts in engagement after the switch has been closed by the pneumatic operating means. The maintaining-coil is not limited in position to that herein illustrated, but may be located in any desired position relative to the movable parts of the switch so long as the object sought is attained.

The customary reversing-switch RS comprises the cylindrical member 23, carrying contactsegments engaging with relatively fixed contact-fingers. The pneumatic operating means is connected to said cylinder through thelever-arm 24, to the opposite ends of which are pivoted the piston-rods and 26, respectively, the rod 25 being connected to piston 27, operating in cylinder 28, and the rod 26 being connected to piston 29,0perating in cylinder30. Said cylinders are in communication with the train-

pipes

31 and 32, respectively, through the connecting-

pipes

33 and 34, the quick-acting exhaust-valves 35 and 36, and the cut-off valves 35 and 36. The exhaust-valves each comprise a piston 37 operating in cylinder 38, held in the position shown in Fig. 3 by means of spring 39, and normally connecting the cylinder 28 or 30 to atmosphere through the ports 40 and 4:1. The normally open cutoff valves 35 and 36 are carried by valvespindles attached to the piston 37 and control the ports a0 between

pipes

33 and 33 and also between

pipes

34 and 34;. The pistons 27 and 29 control ports in the upper part of each cylinder 28 and 30, communicating with the pipe 42, which leads to the controller-contact-operating means. These ports are also controlled by the valves 43 and a l, the spindles of which are operatively connected, by means of links 45 and 46, respectively, to the reversing-switch cylinder 23 or lever 24:, so that considering valve 4A the communication is established between the cylinder 30 and pipe 42 when the port leading to said pipe is uncovered by the piston 29 during its upward movement, but is closed when the said port is uncovered by the said piston 29 during its downward movement.

The pipe 42 leads to the series-parallel valve P, controlling the admission of compressed fluid to the series and parallel contactoperating means. This valve normally, as shown in Fig. 3, permits communication to be established between pipe 42 and pipe 47,

- leading to the series-contact-operating means,

and consists of the slide-valve 43, operating in casing 4 1* and maintained at one end of its travel by means of spring 4:5and moved to the other end of its travel by means of solenoid 46, the core of which is connected to the valve-spindle. The pipe 4E8, leading to the parallel-contactoperating means, is normally con nected to atmosphere through the passageway 9 in Valve 43 and the exhaust-port 50.

When a controller eontact has operated, it operates the valve B in the pneumatic system, which admits compressed air to the actuating-cylinder of the contact next in advance, thus producing a progressive operation of the controller-contacts. ,I. prefer to employ for this valve B that shown in section in Fig. 5. This is a double-globe valve. The interior valve 51 is mounted by a lost-motion connection on valve-spindle 52 and is held in its seat 53 by gravity, assisted by the pressure in the pipe when such pressure exists. Said valve is lifted from its seat by the engagement of the collar 54 therewith during the upward movement of spindle 5'2. The exterior valve 55 is normally open, exhausting to atmosphere the actuating-0y]inder of the next contact in advance. This latter valve is mounted slidably on spindle 52 and is moved to its seat 58 and held lirmly thereon by the compression of spring 56 during the upward movement of spindle 52. In its closed posi tion the collar 57 practically engages the valve 55, precluding any possibility of said valve opening. due to pressure within the pipe so long as the piston-rod 16 of the controller-contact-operating means is in engagement with the valve-spindle 52 and said contact is completely closed. The valve is arranged to close before the valve 51 opens and the valve 51 to close before the valve opens.

l/Vhen the series contact 6 operates, the compressed air is admitted through valve B, operated by said contact-operating means, to the pipe 60, leading to the pipe 61, which communicates with the resistance-con trolling-com tact-operating means; also, when the parallel contacts are operated the compressed air is admitted through the valve B operated thereby to the pipe 62, connecting with said pipe 61. It is necessary with such connections to prevent the compressed air in the pipe 60, when the motors are connected in series, entering pipe 62 through the connection-of the latter with pipe 61. If such a communication was established, the pipe 60 would be exhausted directly to atmosphere and the resistance-controlling cont-acts would not be operated. To prevent this condition, 1 provide at the junction of pipes 60, 61, and 62 an automatic double-acting valve D, the preferred form of which is shown in section in Fig. 4:. This valve is provided with the passage-way 63, which normally registers with the port 64: in the valve-casing and exhaust-pipe 61 to atmosphere. The valve is normally held in the position shown in Fig. 4: by means of the springs 65 and 66, located between the valve ends and the

collars

67 and 68, fastened to the valve-casing. 1f pressure exists in pipe 60, the valve is moved upwardly, compressing spring 65, closing port 64, and connecting pipe 60 with pipe 61 through passage-way 70; also, if pressure exists in pipe 62 the valve will be moved downward, compressing spring 66, closing port 64:, and connecting pipe 62 to pipe 61 through passageway 69. It will thus be-seen that the passage-way between pipes 60 and 62 is effectively blocked without affecting the desired communications between pipes 60 and 61 and pipes 62 and 61 during the operation of the controller.

To check the automatic progression of the contacts when the current in the motor-circuit rises above a predetermined value, 1 provide a throttle-valve 71 in pipe 61, maintained normally open by spring 72 and closed to cut 01f the supply of air to the resistance-controlling-contact-operating means by the solenoid 73, connected in the motor-circuit, as shown in Fig. 1.

The master-controllers or controlling devices are illustrated in Fig. 1 at C and C These controllers may be located at any desired points on the car or train. The mastercontroller C is shown in diagrammatic development in Fig. 3 as a slide-valve, the movable member f of which is provided with the passage-waysf and f adapted to establish communication between the train-

pipes

31 and 32 and the source of compressed-fluid supply, the latter being here illustrated as a motordriven air-compressor 74, connected to reservoir 75. The passage-waysf and f register with the ports j, and f in a manner to be hereinafter described.

One of the relays for controlling the parallel valve P is indicated at K. This relay is operated mechanically by the piston-rod 16 of contact 12, the last resistance-controlling contact, and is maintained in its operated position with its bridging member 80 in engagement with contacts 81 by means of the solenoid 82. This solenoid is connected in circuit with the solenoid 46 of the valve P and also with the

contacts

100 and 101 of the pneumaticallyoperated relay S.

The connections to the solenoid 46 are so arranged that the valve P cannot operate until the pneumatically-operated relay S has its bridging contact 101 in engagement with contacts 100 and the relay K is closed. The relay S in addition to controlling valve P also controls the supply of current to the maintaining-circuit,including the maintaining-coils 18. The actuating means of this relay are connected to the train-pipes, the cylinder 111, containing piston 112,being connected to trainpipe 31 through pipe 109 and the cylinder 113, containing piston 114, being connected to train-pipe 32 through pipe 110. Each piston is maintained in the lower part of its cylinder by gravity, assisted by springs, if so desired, and is connected through pistonrods to the cross-bar 115, the piston-rod of piston 112 being pivotally attached at 107 and the piston-rod of piston 114 being piv-- otally attached at 108. Pivotally suspended at 106 from bar 115, but insulated therefrom, is the bridging contact 101. Projecting from opposite ends of bar 115 and insulated therefrom are bridging

members

103 and 105,

which engage

contacts

102 and 104, respectively. The arrangement of this relay S is such that when air is admitted from pipe 31 to cylinder 111 the piston 112 is raised and contacts 104 are bridged, the bar 115 swinging about 108 as a pivot. When air is admitted to cylinder 113, the piston 114 is raised and contacts 102 are bridged, the bar 115 swinging about 107 as a pivot. In neither of these cases does the member 101 engage contacts 100. This latter is accomplished only when both pistons are raised at the same time that is, only when pressure is admitted to both train-pipes.

Also located in the parallel control-circuit in series with solenoid 46 is the operatingsolenoid 83 of therelay B. This relay opens the maintaining-circuit while the valve P is operating to change the connections of the operating means of the motor-controller contacts from series to parallel, and vice versa. The operation of this relay permits the controller-contacts to open before the motors are connected in parallel after being connected in series, and vice versa. The core 84 of this relay R is fastened to the bridging contact 85, and the latter is fastened to the bridging contact 86 by means of spring 87. Both bridging contacts 85 and 86 are adapted to engage fixed contacts 88, which are connected to the current supply or trolley T through contacts 102 to 105, inclusive, of relay S. The bridging contact 86 is provided with a dash-pot 89, which slightly retards the action of said contact when the relay is operated.

Of the three cars A, A and A (shown in Fig. 2) A and A are motor-cars. The positions of the motor-controllers are indicated at G, the master-controllers at G and G the motors at M and M and the trolleys or collector-shoes at T.

The operation of this improved system of motor control will now be described. Let us suppose the master-controller, Fig. 3, is moved into its first operative position in one direction, (indicated by 1 1 Forward) The pas sage-way f is thus brought into register with portsf and f admitting compressed air from reservoir 75 to train-pipe 32. The air then enters cylinder 113 of relay S through pipe 110, moving piston 114 upward to bridge contacts 102. The maintaining -circuit is thus completed and may be traced as follows: from trolley T through

contacts

102 and 103 of relay S,

contacts

85 and 88 of relay R, and coils 18 to ground. The compressed air also passes through pipe 34, valve 36, pipe 34, and valve 35 into cylinder 28, forcing piston 27 upward to throw reversing-switch RS into the reverse of the position shown in Figs. 1 and 3. Piston 27 then uncovers the port leading to pipe 42 through valve 43, the latter valve being also opened by this movement of the reversing-switch.

When the valve 35 is raised to admit air to cylinder 28, it also closes cut-off valve 35 to prevent air from entering cylinder 30 from train-pipe 31. The air after entering pipe 12 flows into casing of valve P, thence into pipe 47 and cylinder 17 of series contact 6. As said contact 6 closes the piston-rod 16 engages valve-spindle 52 and operates valve B of said contact. The air is thus admitted to pipe 60 and thence passes through automatic valve Dand thrttle-valve 71 into the operating-cylinder of the first resistance-controlling contact 9. This latter contact as it closes opcrates its corresponding valve B to admit air to the cylinder of contact 10, which latter operates its valve B to admit air to cylinder of contact 11. The contact 11 in turn controls the admission of air to cylinder of contact 12, thus producing an automatic progressive operation of the controller-contacts.

The maintaining-coils 18 assist to a certain extent the closing of the controller-contacts and also assist the meumatic-operating means in holding said contacts closed; but said coils actually maintain the contacts which have already been operated whenever the throttlevalve 71 operates to cut off the supply of air and check the progressive operation of the resistance-controlling contacts as the result of an overload in the motor-circuit.

The motor-circuit corresponding to the series position of the motor-controller with the

contacts

6 and 9 operated may be traced on Fig. 1 as follows: from the trolley or collector shoe T, conductor 90, contact 9, resistance 13, conductor 91, reversing-switch RS, armature of motor M, reversing-switch, throttle-valve solenoid 73, field-coil of motor N conductor 92, series contact 6, conductor 93, reversing-switch, armature of motor M, reversing-switch, and field-coil of motor M to ground or return. As the contacts 10 and 11 operate the resistance-sections 1 1 and 15 are successively thrown in parallel with resistance 13 in the motor-circuit, thus reducing the resistance of said circuit. Contact 12, the last to operate, short-circuits the resistancesections and connects the motordirectly in series without external resistances.

Now if it is desired to connect the motors in parallel relationship the master-controller is moved farther in the same direction into the parallel position indicated by 2 2, Forward, thus bringing the port f also into register with passageway f and admitting air from reservoir into both train-

pipes

31 and 32. The admission of air to pipe 31 does not affect the position of the reversing-switch, since, as before stated, the cut-01f valve 35 is now closed. The relay S is, however, operated so as to bring bridging-contact 101 into engagement \vithcontacts 100, thereby completing the parallel control-circuit, which may be traced as follows: from trolley T, through

contacts

100 and 101, actuating-coil 82 of relay K, which has previously been mechanically closed by the operation of controller-contact 12, thence through contacts and 81 01 said relay K, through coil 83 of relay R and coil 16 of valve P, to ground. The energization of this circuit causes the relay R to operate to move bridging-contact away from contacts 88 and open the maintaining-circuit. This permits the controller-contacts to open while the valve P is being operated to establish parallel connections of the pneumatic actuating system. When the valve P has completely operated, the bridging-contact 86 of relay 1% is moved into engagement with contacts 88 and reestablishes the maintaining-circuit. The length of time the n'iaintainingcircuit is opened at relay R is regulated by adjusting the dash-pot 89.

As the valve P is operated by the solenoid 46 the pipe 47 is first connected to atmosphere through passage-way 19 and exhaustport 50, thus exhausting the air simultaneously from cylinder 17 of contact 6 and from pipe 60. This permits the contact 6 to open and the valve .D to assume its mid-position, so as to exhaust pipe 61 through the port 6 1 in said valve, thus permitting the resistance-controlling contacts to open approximately simultaneously. The rapidity of opening of these contacts is increased by the fact that all the air in the operating-cylinders need not pass through the port 64; in valve 1). On the contrary, the exhausting-ports of each of valves B of contacts 9 to 12, inclusive, open immediately to permit the air from the cylinder of the contact next in advance to exhaust therethrough. The controller-contacts are now all open. It will be clear, however, that the relay K will not open at this time to interrupt the parallel contact-circuit so long as sufiicient current flows through its coil 82. hen the valve P reaches the limit 01 its downward movement, the compressed air flows from pipe 12, through the valve-casing into pipe 18, and thence into cylinders of parallel contacts 7 and 8. These contacts as they close operate their valves B to admit compressed air to pipe 62. The valve D is then automatically operated to connect pipe 62 to pipe 61, and the air passes through said valve D, valve 71, and pipe 61 to cylinder of contact 9. The resistance-controlling contacts then operate in automatic progression, as before described, to reduce the resistance of the motor-circuit step by step. The throttle-valve 71 operates when the current in the motor-circuit rises above a predetermined value to check this automatic progression, as before described.

The motor-circuits corresponding to the first parallel position of the motor-controller with contacts 7, 8, and 9 closed may be traced on Fig. 1 as follows: from trolley T, through conductor 90, contact 9, resistance 13, conductor 91, reversing-switch, armature of motor M, reversing-switch, solenoid 73, fieldcoil of motorM, conductor 92, controller-contact 8, conductor 97, to ground; also branching at point 96, through conductor 95, contact 7, conductor 93, reversing-switch, armature of motor M reversing-switch, field-coil of motor M to ground.

When the master-controller is moved into its midposition, the train-pipes are exhausted, thus permitting all parts of the system to assume their initial position. The reversingswitch remains in the position into which it has been thrown until it is desired to operate the car or train in the reverse direction of movement. To accomplish this reversal, the master-controller is thrown into its Reverse position, thereby admitting compressed air to the train-pipe 31 before admitting it to both pipes. In the series position the air passes into cylinder 111 of relay S to complete the maintaining-circuit at

contacts

104 and 105. The air also passes into cylinder 30 of the reversing-switch through pipe 33, valve 35, pipe 33, and valve 36, thus throwing the re- Versing-switch in the position shown in Fig. 3 and uncovering the port leading to pipe 42 through valve 44, it being understood that valve 43 is closed when valve 14: is open, and vice versa. The automatic progression of the controller-contacts then takes place as above described.

If the master-controller is thrown at once from its mid or off position into its final position or parallel position either forward or reverse, the control system will operate, as above described, to connectv the motors first in series with resistance, then cut out said resistance, leaving the motors connected in series, then automatically open the motor-circuit, then reestablish said circuit with the motors connected in parallel with resistance in circuit therewith, then cut out said resistance step by step, leaving the motors in parallel.

Many changes and modifications may be made in the arrangement of the system and the construction of parts thereof without departing fromthe spirit of the invention, and I aim in the appended claims to cover all such changes and modifications.

WVhat I claim as new, and desire to secure by Letters Patent of the United States, is-

1. In a system of motor control, a plurality of motors, a motor-controller comprising a plurality of separately-actuated contacts including resistance-controlling contacts, pneumatic operating means for said contacts, means for producing an automatic progressive operation of said contact-operating means, means independent of the contact-operating means for maintaining said resistance-controlling contacts, means for checking the automatic progression of the resistance-controlling conswitch, two pipes connected to the operating means of the reversing-switch and contacts, and a master-controller for regulating the admission of compressed fluid to said pipes to control said reversing-switch and motor-com troller.

2. In a system of motor control, a plurality of motors, a motor-controller comprising a plurality of separately-actuated contacts in cluding resistance-controlling contacts, pneumatic operating means for said contacts, means for producing an automatic progressive operation of said contact-operating means, means independent of the contact-operating means for maintaining said resistance-controlling contacts, means for controlling the admission of compressed air to said operating means, and a pneumatically-operated relay for controlling said independent maintaining means.

3. In a system of motor control, a plurality of motors, a motor-controller comprising a plurality of separately-actuated contacts including resistance-controlling contacts, pneumatic operating means for said contacts, means for producing an automatic progressive operation of said contact-operating means, means independent of the contact-operating means for maintaining said resistance-controlling contacts, means for controlling the admission of compressed air to said operating means, a

pneumatically-operated relay for controlling said independent maintaining means, and a throttle-valve controlled by current in the motor-circuit for cutting 01f the supply of air to said contact-operating means to check the automatic progression without affecting the contacts already operated.

4:. In a motor-controller of the separatelyactuated-contact type, resistance-controlling series and parallel contacts, with pneumatic operating means therefor, a valve for controlling the admission of air to the series and parallel contact operating means, and a pneumatically-operated relay for controlling the operation of said valve.

5. In a motor-controller of the separatelyactuated-contact type, resistance-controlling series and parallel contacts, with pneumatic operating means therefor, a valve for controlling the admission of air to the series and parallel contact operating means, a pneumatically-operated relay, and a relay operated by one of the resistance-contact-operating means, it being necessary for both said relays to be in the closed position before said valve can be operated.

6. In a motor-controller of the separatelyactuated-contact type, resistance-controlling series and parallel contacts, with pneumatic operating means therefor, a valve for controlling the admission of air to the series and parallel contact operating means, and a pneumatically-operated relay for controlling the tacts, a pneumatically operated reversingl operation of said valve, a source of compressed fiuid supply, and two pipes connected to said relay and valve, the arrangement being such that the relay cannot operate to permit the valve to be operated until the compressed air is admitted to both pipes at the same time.

7. In a system of motor control, a motorcontroller comprising a plurality of separately-actuated contacts with pneumatic operating means therefor, electric maintaining means independent of said operating means, a pneumatically-operated relay or relays controlling said maintaining means, and a master controlling-valve for said operating means and said relay or relays.

8. In a series-parallel motor-controller ot' the separately-actuated-contact type, pneumatically-operated contacts, a pneumaticallyoperated reversing-switch, a pneumatic actuating system, means controlled by the operating means'of the reversing-switch for rendering said actuating system operative as to the series contacts, a valve for rendering said actuating system operative as to the parallel contacts, and a pneumatically-operated relay controlling said valve.

9. In a series-parallel motor-controller of the separately -actuated-contact type, pneumatically-operated contacts, a pneumaticallyoperated reversing-switch, a pneumatic actuating system, means controlled by the operating means of the reversing-switch for rendering said actuating system operative as to the series contacts, a valve for rendering said actuating system operative as to the parallel contacts, and a pneumatically-operated relay controlling said valve, two pipes connected to said reversing-switch-operating means and to said relay, and a master controlling-valve for controlling the admission of compressed air to said pipes, the reversing-switch operating when air is admitted to either pipe and the relay operating when the air is admitted to both pipes.

10. In a series-parallel motor-controller ot' the separately-actuated-contact type, pneumatically-operated contacts, a pneumaticallyoperated reversing-switch, a pneumatic actuating system, means controlled by the operating means of the reversing-switch for rendering said actuating system operative as to the series contacts, a valve for rendering said actuating system operative as to the parallel contacts, electric maintaining means for certain of said contacts, and a pneumatically-operated relay or relays for controlling said valve and said maintaining means.

11. In a system of train control, each of a plurality of cars having a motor-controller comprising a plurality of separately-aetuated contacts, pneumatic actuating means for said contacts, electric maintaining means for said contacts, a pneumatically-operated relay or relays for controlling said maintaining means,

and a pneumatic train system connected to said actuating means and to said relay.

12. In a system of train control, each of a plurality of cars having a niotor-eontroller comprising a'plurality of separately-actuated contacts, pneumatic operating means for said contacts, electric maintaining means independent of said operating means, a pneumatically-operated relay or relays controlling said maintaining means, two train-pipes connected to said operating means and said relay or relays, and means for controlling the pressure in said train-pipes.

13. In a system of train control, each of a plurality of cars having a motor -controller comprising a plurality of separately-actuated contacts, pneumatic operating means for said contacts, electric maintaining means independent of said operating means, apneumaticallyoperated relay or relays controlling said maintaining means, two train-pipes connected to said operating means and said relay or relays, and a master controlling-valve adapted to admit air to either or both of said pipes, the relays being arranged to operate when air is admitted to either pipe.

14. In a system of train control, each of a plurality of cars having amotor-controller olf the separately-actiiated-contacttypeincluding resistance-controlling series and parallel contacts, with pneumatic operating means there for, a valve for controlling the admission of air to the series and parallel contact operating means, a pneumatically-operated relay for controlling the operations of said valve, and a pneumatic train system for controlling said relays and contact-operating means.

15. In a system of train control, each of a plurality of cars having a motor-controller of the separately-actuatedcontact type including resistance-controlling series and parallel contacts with pneumatic operating means therefor, a valve forcontrolling the admission of air to the series and parallel contact operating means, a pneumatiCally-operated relay for controlling the operation of said valve, two trainpipes connected to said relays and said contactoperating means, and a master controllingvalve adapted to admit compressed airt'rom a source of supply to either or both of said pipes, the arrangement being such that the relays operate when air is admitted to both train pipes.

16. A system of train control, in which each of a plurality of cars is equipped with a motor-controller of the separately-actuatcd-contact type with pneumatic actuating means for the contacts, means independent of the contact-actuating means for maintaining the contacts, and a pneumatic train system for controlling the actuating and maintaining means.

17. A system of train control, in which each of a plurality of cars is equipped with a mo- In witness whereof I have hereunto set my hand this 24th day of January, 1905.

CHARLES E. LORD.

Witnesses:

BENJAMIN B. HULI, HELEN ORFORD.