US1412528A - System of control - Google Patents

Description

H. H. JOHNSTON.

SYSTEM OF CONTROL APPLICATION F ILED JUNE 9,1919.

Patented Apr. 11, 1922.

' To r Cor r ffibller INVENTOR Howard Hdo/msi'bn.

7 AfToRNEY WITNESSES:

x Reverse Opemfibn UNITED STATES PATENT-J'OFFICE.

HOWARD H. OHNSTON, 0F EDGEVOOD BARK, PENNSYLVANIA, ASSIGNOR TO WEST- INGHOUSE ELECTRIC & MIAN'UFACTURIN G GOLMPANY, A CORPORATION OF PENN- SYLVANIA.

SYSTEM- or coivr'non Application filed June 9,

To all whom it may concern:

Be it known that I, HOWARD H. JoHNs'roN, a citizen of the United States, and a resident of Edgewood Park, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Systems of Control, of which the following is a specification. I 4

My invention relates to systems of con-' trol and it has special relation to the control of industrial locomotives or the like that may be governed both from within the vehicle and from a tower or control room alongside the track. 1 a

In connection with the loading of coal cars from overhead bins by means of the familiar chute method, it is impossible for an operator upon the locomotive to determine the proper distance to move the train, as each car is filled, in order to place the succeeding car under the coal chute. However, such control-of the train may readily be effected from a tower or control room near the coal-loading apparatus.

It is an object of my invention, therefore, to provide a combined control system for industrial locomotives whereby the operation thereof during the hauling of full or empty cars may be governed from an operators stand within the vehicle, whereas, during the above-mentioned loading operation, the movements of the train, both in direction and magnitude, may be controlled from a tower near the track.

Another object of my invention is to provide a positive and a negative third-rail shoe or current-collector for use in connection with both the main and the auxiliary control circuits of a locomotive, together with another shoe or current-collector that may be energized, either positively or negatively, to determine the direction ofoperation of the electric locomotive during either type of control of the locomotive, that is, either from within or without the vehicle.

Another object of my invention is to provide a plurality of relay devices that are associated with the above-mentioned can rent collectors and the reversencontrol apparatus for the propelling motors in such manner that one or another of the relay devices shall be energized to effect the operai Specification of Letters Patent. Patented Apr, 11 1922,

1919. Serial No. 302,756.

tion'of the proper switching apparatus to ensure the desired direction of movement of the vehicle. y

Another object of my invention is to provide means for effecting the actuation of the directional control switches immediately upon the energization of the above-mentioned relay devices when tower control is utilized, under which conditions the reversing and accelerating control apparatus in the locomotive are placed in disconnected or inoperative positions. 7

A further object of my invention is to provide a system of the class under consideration wherein automatic acceleration of the propelling motors, through a predetermined number of steps, is effected when operating from the tower, whereas, partial au tomatic operation and partial hand operation are provided when the locomotive is operated from its owncab.

Another object of my invention is to provide suitable electrical interlocking between the various switches and the relay devices so that the proper sequenceof operation is ensured and also relatively low potentials are employed in the auxiliary control sys-, tem to decrease the necessary amount of insulating material and the degree of burning of the interlock contact segments and fingers. y

Other ob ects of my inventlon Wlll become evident from the following detailed description, taken in conjunction with the accompanying drawing, whereim- Figure 1. is a diagrammatic view of the main circuits of a system of control employed in connectionwith my invention;

Fig. 2 is a diagrammatic view of the auxiliary governing circuits for the system that is shown inFig. 1; and

Fig. 3 is a sequence chart of well-known form for indicating the proper order of operation of the various illustrated controlling switches.

Referring. to Fig. 1 of the drawing, the main system here shown comprises suitable supply-circuit conductors, such as third-rails 11 and 12, for. supplying energy, through over-running third-rail shoes or other ourrent-collecting devices 11 and 12, to a plurality of electric motors respectively havin connm-itator-type armatures A1 and A2 and series field windings F1 and F2. A. plurality of accelerating resist rs 9 and 10 and controlling switches LS1, LS2, S, G1, G2,

practice.

The &11X]llflly system shown in Fig. 2 comprises actuating coils for the various switches that are shown in 1, together with electrical interlocks or auxiliary conact members that are actuated by certain 0 the switches, in accordance with the tan'iiliar construction that is shown in connection with the switch LS2 in Fig. 1, and, in addition, a master controller ML, having a plurality of operative positions a to z, inclusive, a master reverser MB, a ci'ltout s itch 15, a tower controller 150, a plurality of relay devices 16 and 17 oi? the double-disk type and a control resistor 18 are provided for selectively ZJOVGl'DlHg the operation of the variois switches in accordance with the sequence that is indicated by Fig. 3. In addition to the supply-circuit conductors 11 and 12, a third supply conductor 13, which may be engaged by an llllltlfiblllllning shoe 13', is provided for eilectins a certain portion of the locomotive control and is adapted to assume either positive or negative polarity, in accordance with the will of the operator, for purposes to be set forth.

Assuming that it is desired to effect opera-- .tion of the locomotive during the hauling period when control from within the locomotive cab is most suitable, the cutout switch may occupy either its illustrated. oi f po. tion or the position marked Cab, while the master rev-rser MR initially occupies its oil position.

Upon movement of the master controller M0 to its in tial operative position a, one circuit is established from the positive supply-circuit conductor 11 through shoe 11, conductor 20, train-line conductor 21, conductors 22 and 23, control fingers 2 1 and 25, which are bridged by contact segment 26 of: the master controller, conductor 27, train line conductor 28, conductor 29, resistor 30, actuating coil 31 of the relay device 17. con ductor 32, trainline conductor and conductor 3 1, to the currentcollecting; device 13 and the associated stationary conductor 13, which, under the present lnOpOlntlVG conditions, therefore, is of positive polarity. However, the circuit just traced is not completed until the masteflreverser MB is actuated to the one or the other of its operative positions, subsequently described in detail.

A further circuit is continued from the conductor through conductors i and 41,

control resistor 18, conductors 12, 4.3, it and as, control fingers lti and -17, which are bridged by contact segment 18 oi. the master controller, conductors 4-9 and 50, train-line conductor 51, conductor 52 and shoe 12 to the negative supply-circuit conductor 12. The control resistor 18 is thus connect-ed between the positive and negative supply-circuit conductors and is enrployed to provide suitably low operating voltages, by means of properly placed taps, to the actuating coils for the various switches.

It the master reverser MR is now moved to its forward position, a new circuit is continued from the conductor through contact segment 38 of the master reverser and conductor 39 to the train-line conductor I133, whereby the auxiliary current-colleoting device 13 and the directly-connected circuits are made of negative polarity correspending; to that of the conductor 50. Con sequently, the circuit previously traced through the actuating; coil 231 of the relay device 17 is energized. to cause the relay device to assume its upper position.

Under such conditions. a circuit is cstablished from an intermediate tap-point 5!) of the control resistor 18 through condut tors 5 1, 55, 56 and 57, lower contact disk 58 of the relay device 17, in its upper position, conductors 59, upper contact disk 60 ot the relay device 16, in its normal or lower position, conductor 61, the parallel-related actuating coils of the switches 2 and 4-, and interlock l-out to conductor (52, a branch circuit being also energized and traversing the pal allel-related actuating coils of the switches (3 and 8 and interlock 5-out to the coinluctor 02, whence a common ci 'cuit is completwl through conductor (53 to the negative conductor L2.

The directional switches 2, G and H, (orresponding to forward operation, are thus closed, as indicated. by the correspmidiiug cir cles in step a of the sequence chart, Fig. 3.

Upon the closure ot'the switches i and F5. a further circuit is completed li'o'rn the couductor i0 through resistor (Tel, an actuating coil marked Brake release series-connected interlocks e1--in and Sin and conductor to negative conductor 44. In this w y. the electric or electro-pneumatic brakes with which the vehicle is equipped are automatically released as soon as the directional switches a and 8 are closei'fl and betore the line switch LS1 is closed to connect the motors to the supply circuit.

Another circuit is established. at this time, from a second intermediate tapimint {it of? the control resistor 18 through conductor (7, interlock LS2-out, actuating coil of the switch 5, interlock G2-out, and coinluctoi-s ($8, and 541: to the tap-point 5;; o! the control resistor 18.

The switch 9 is thus closed previourii to the Hit) connection of the motors to the supply circuit, which may be accomplished by actuating the master controller to its position Z).

In position 7), a new circuit is established from the tap conductor 67 through conductor 69, parallel-related actuating coils of the switches LS1 and G1, conductor 70, a suitable Brakes-Released interlock, trainline conductor 71, conductor 72, control fin gers 7 3 and 7 4, which are bridged by contact segment 75 of the master controller, conductor 76, train-line conductor 77 and conductors 78, 56, 55 and 54 to the tap-point 53 of the control resistor 18. i

The motors are thus connected, in series relation with the accelerating resistors 9 and 10, across the supply circuit,in accordance with the following series of connections: from the positive supply-circuit conductor 11 through shoe 11, switch LS1, the entire accelerating resistor 9, armature A1, switch 2, field winding F1, switch 4, conductor 35, actuating coil of the current relay orlimit switch 14, junction-point 36, switch S, the entire accelerating resistor 10, armature A2, switch 6, field winding F2, switches 8 and G1 and conductor 37 to the negative current collecting device 12. I

Upon the closure of the line switch LS1, a new auxiliary circuit is established from the tap-conductor 54 through conductors 55, 68 and 80, contact disk 81 of the current relay 14, when the motor current has decreased to a value corresponding to the lower position of the limit switch, whence circuit is continued through conductor 82, interlocks LS1 in and Rl-out, conductor 83 and the actuating coil of the resistor-short-circuiting switch R1, to negative conductor 43.

As soon as the switch R1 has closed, an interlock Rl-in is connected in series relation with an interlock LSl-in between the tapconductor 54 and the positive terminal of the actuating coil, wherebythe switch is subsequently maintained closed, irrespective of the condition of the limit switch 14.

When the current relay 14 has again dropped to its lower position, a progression circuit is established from the conductor 82 through interlocks LSl-in, Rl-in, R2-out and the actuating coil of the resistor-short circuiting switch R2 to negative conductor 63.

A holding interlock R2-in serves to connect interlock LSl-in and the tap conductor 54 directly to the actuatingcoil of the switch R2, as soon as the switch has closed. I

WVhen the current relay 14 again assumes its lower position, a circuit is established LSl-in, Rl-in, R2-in and R3 out, whence circuit is continued through the actuating coil of the resistor-short-circuiting switch R3 to the negative conductor 63. Upon the closure of the switch, a holding interlock R3-in is from the conductor 82 through interlocks connected in circuit similarly to the previously mentioned holding interlocks Rl-in and R2-in.

The accelerating resistor 9 is thus gradually short-circuited, through the automatic action of the current relay 14, to effect a predetermined degree of acceleration oithe propelling motors, the master controller MG remaining in position 1) throughout such automatic accelerating period.

Upon movement of the master controller to its position 0, the contact segment engages control finger 84, whence circuit is completed through conductor 85, train-line conductor 86, conductor 87 and the actuating coil for the switch R4 to negative conductor 63. v

In a similar manner, contact segment 75 successively engages control fingers 88 and 89 in positions cl and e of the master controller to energize conductors 90 and 91 and the actuating coils for the switches R5 and R6, respectively. The other accelerating resistor 10 is thus gradually short-circuited by hand operation, that is, by successive movements of the master controller MC, and, consequently, the motors are connected in fullseries relation, corresponding to vposition e of the master controller. 7 To effect the transition of the motors to parallel relation, the master controller is moved, through its transition position, to the initial parallel position f. In the first place, the switches R4, R5 and R6 are opened by reason ofthe de-energization of the cor responding control fingers 84, 88 and 89 of the master controller. In this way the accelerating resistor 10 is included in circuit with the armature A2 during the transitional and the initial parallel operating periods. Furthermore, during the transition,'a new auxiliary circuit is established from the tapconductor 67 through conductor 92, actuatingcoil of the switch G2, conductor 93, train-line conductor 94, conductor 95 and control finger 96, which is engaged by the master-controller contact segment 75. The switch G2 is thus closed to eifect the closure of a temporary shunting circuit including the resistor 10 around the armature A2 and I ther auxiliary circuit is established from the conductor 92, through interlock S-out and the actuating coil of the switch LS2 to conductor 93. i r a In this way, the series-connecting switch S is opened, while the parallel-connecting line switch LS2 is closed. The main circuits, at this time, may be traced as follows. One

circuit is established from the positive current-collecting device 11 through switches LS1, R1, R3 and R5, armature A1, switch 2, field winding F1, switch 1, conductor 35, actuating coil of the current relay 1 1, junctionpoint 36, conductor 100, switch G2 and con ductor 37 to the negative shoe 12. A branch circuit includes conductor 101, switch LS2, accelerating resistor 10, armature A2, switch 6, field winding F2, switches 8 and G1 and negative conductor The main machines are thus connected in parallel relation, the resistor 10 being connected in circuit with the machine having the armature A2.

In positions 9, h and i of the master controller, the contact fingers 8 1-, 88 and 89 are again successively engaged by the contact segment 75, whereby the switches R4, R5 and R6 are closed in that order to gradually short-circuit the resistor 10.

lVhenever reverse operation of the locomotive (at rest) from the cab thereof is desired, the master controller is moved to its initial position a, and the master reverser MR is actuated from its off to its reverse position Rev. Consequently, a circuit is established from the positive current-collecting device 11' through conductor 20, trainline conductor 21, conductors 22 and 102, contact segment 108, corresponding to reverse position of the master reverser, conductor 39, train-line conductor 33, and conductor 3 1 to the auxiliary contact shoe 13', which, in the present instance, is thus made of positive polarity, which is the opposite to that assumed when forward operation of the vehicle was to be effected. In other words, the auxiliary shoe 13 is oppositely energized in accordance with, and to determine. the direction of, operation of the vehicle.

Since conductors 29 and 32 are now both of positive polarity, no movement of the relay device 17 occurs, as was the case during forward operation of the vehicle. However, a new circuit is established from the positively energized conductor 32 through conductor 104-, actuating coil 105 of the relay device 16, a resistor 106 and conductor 4: 1,

whence circuit is completed, as already traced, to the negative contact shoe 12.

In this way, the relay device 16 is actuated to its upper position to complete a circuit from tap-conductor 54- through conductors 55, 56 and 57, contact disk 108 of the relay device 17, in its normal lower position, conductor 109, contact disk 110 of the energized relay device 16 in its upper position, conductor 11.1, pz'irallel-related actuating coils of the switches 1 and 3, and interlock 2-out to conductor 112, a branch circuit including parallel-related actuating coils of the switches 5 and 7 and interlock 6-outto the conductor 112, whence a common circuit is completed tl'irough conductors 62 and ()5 to the negative terminal of the control resistor 1], as previously set forth. Consequently, the directional switches 1, 2i, 5 and T, correspending to reverse operation of the vahicle, are closed, as indicated by the crosses in step a of the sequence chart,l*ig.

It is believed that the function of the switches 1, 3, 5 and 7, whereby the connection of the field windin s, with respect to the corresponding armatnres of the main system shown in Fig. 1, are reversed, will be readily understood without requiring a detailed tracing of the main circuits.

Upon the closure of switches 3 and 7, the circuit of the brake-release magnet is completed through interlocks 3-in and 7-in, which bridge the interlocks d-in and S-in described above in connection with forward operation of the vehicle. The remaining operation of the system from the locomotive cab to effect complete series-parallel connections of the propelling motors is identical with that already set forth, and no further exposition thereof need be given here.

Under the loading conditions of the train as previously mentioned, the control thereof is effected from a station or tower near the loading apparatus. The train operator, therefore, returns the master emit-roller and the master reverser to the illustrated off positions and actuates the cut-out switch 15 to its position Tower.

If it is then desired to effect a forward operation of the train to properly spot a car that is to be loaded, the tower operator actuates the switch or controller 15 into its forward position.

A circuit is thereby established from the negative supply conductor 12 through conductor 116, contact segment 119 of the tower controller and conductor 117 to the auxiliary supply-circuit conductor 13, whereby the auxiliary contact shoe 13 is made of negative polarity, as was the case when forward operation of the vehicle from within the locomotive cab was effected.

Ilpon the negative enei \tion oi the contact shoe 13 and the directly associatiu'l circuits, a circuit in the li'icomotivc is established from the positive onrrcnt-colleci.int! device 11, through conductor 20. train-linc conductor 21, conductors and 120, control lingers 121 and 122, which are bridged by contact segment 123 of the cutout switch 15, whence circuit is completed through conductors 123a. and 27, train-line coinluctor 28 and conductor 29, to the ctuating coil 2-1 of the relay device 17, corrcsgiiending to forward vehicle operation, which coil is connected to the auxiliary contact shoe 121. Since this shoe has been made of negative polarity by TQHSOH of the previmisly-described actuation of the tower controller 151 the relay device 1'? is actuatial to its upper position in'iincdiately upon the operatimi of the tower controller and, consequently, the

forward directional switches 2, at, 6 and 8 are closed. Q

Likewise, the control resistor 18 is energized by reason of its: connection to the positively energized conductor 29, and the switch S is, therefore, closed in accordance with the previously-traced circuits. The f brake-release coil is also energized, at this time, by'reason of the energization of the previously traced circuit fromthe conduc- 1 G1, one end of which circuit is connected to the ta -conductor 67 is continued as far as l conductor 72, in accordance with the previous descrlptlonthereof, whence direct cona contact segment 125 of the cutout switch 15. Consequently, the switches LS1 and G1 are closed to connect the machines in series relation with the accelerating resistors 9 and '10, across thesupply circuit.

Upon the closure of the line switch LS1, the previouslyedescribed automatic progressive operation of the resistor-shortcircuiting switchesRl, R2 and R3, in accordance with the movements of the limit switch 14, isagain efiiected. j

The automatic operation ofthe system to the stage just described is suflicient to efiect the desired spotting of the train and, consequently, no further provision for control of the train from the tower need be-made.

For effecting reverse movement of .the train from the tower, the controller 15a is thrown to its position Rev. whereby the positive supply conductor 11 is connected through conductor 115, contact segment 126 and conductor 117 to the auxiliary supplycircuit conductor 13. In thisway, the auxiliary contact shoe 13 and the directly asso ciated circuits are made of positive polarity, corresponding to the operation of the master" reverser MRfin position Rev. during the operation oil the locomotive from the cab thereof. It will be understood, therefore,

- that, in the present instance, the relay device parts herein set forth, as various modifi ca- I tions thereof may be made without depart ng from the spirit and scope of my invention.

I desire, therefore, that only such'limitations shall be imposed as are indicated in the appended claims.

I claim as my invention: 1. In a system of vehicle control, the com bination with a dynamo-electric mcalnne, 01

a single current-collecting device having different polarities during different operations of the vehicle, and a plurality of constantpolaritycurrent-collecting devices. I

2. In a system of vehicle control, the combination with a dynamo-electric machine, of

3. In a system of vehicle control, the coin bination with a dynamo-electricmachine and a plurality of supply conductors of opposite polarities, of an auxiliary conductor, and

means for connecting said auxiliary. conductor to the one or the other of said supply conductors to effect diflerent operations of nection to conductor 7 6 is made by means of said machine. 7

4. In a system of vehicle control, the com- 5. In a system of vehicle control, the comi bination with a dynamo-electric machine, of

a plurality of re'lay devices for respectively I controlling different operations of said machine, and means for selectively actuating the one or the other of said relay devices to complete certain circuits through the remaining. relay device in its normaliposition to inaugurate the one or the other of such operations. i

6. In a system ofvehicle control, the combination with a dynamo-electric machine, of a plurality of relay devicestfor respectively controlling different operations of said ma chine, a. plurality of supply conductors of opposite polarities, an auxiliary conductor connected to one terminal. of the actuating circuits for said relay devices, and means for connecting said auxiliary. conductor to the one or the other of said supply conductors to actuate the corresponding relay 16 is operated to effect the closure of the device and inaugurate the corresponding machine operation. I

7. In a system of vehicle control, the combination with a dynamo-electric machi'ne, of a plurality of relay devices for respectively controlling the forward orreverse operation of said machine, a plurality of supply conductors of "opposite polarities, an auxiliary conductor connected to one terminal of the actuatingcircuits for said relay devices, and means comprising a reversing-controller for said machine for connecting said auxiliary conductor to the one or the other of said supply conductors to actuate the corresponding relay device and inaugurate the corresponding vehicle operation. a

8. In a system oi? vehicle control. the combination with a dynamo-electric machine, of a plurality of relay devices "for respectively controlling difl'erent operations of said machine, a plurality of. supply conductors of different electrical characteristics, an auxiliary conductor connected to oneterminal of the actuating coils for said relay devices, and means -for connecting said auxiliary conductor to the one or the other of said supply conductors to actuate the corresponding relay device and inaugurate the corresponding machine operation.

9. In a system of vehicle control, the combination with a dynamo-electric machine, of a plurality of relay devices for respectively controlling the forward or reverse operation of said machine, a plurality 0i supply conductors of different electrical characteristics, an auxiliary conductor connected to one terminal of the actuating coils for said relay devices, and means comprising a reversingcontroller for said machine for connecting said auxiliary conductor to the one or the other of said supply conductors to actuate the corresponding relay device andinaugurate the corresponding vehicle operation.

10. In a system of vehiclecontrol, the combination with a dynamoclectric machine, of a plurality of relay devices for respectively controlling forward and reverse operation of said machine, and means for selectively energizing the one or the other relay device to complete certain circuits through its energized position and the normal de-energized position of the remaining relay device to determine .the direction of movement of said machine.

11. In a system of vehicle control, the combination with a dynamo-electric machine, of a plurality of relay devices for respcc tively controlling different operations of said machine, a plurality of supply conductors of opposite polarities, an auxiliary conductor connected to one terminal. of the actuating circuits for said relay devices, and means for connecting said auxiliary .conductor to the one or the other supply eonductors to energize the one or the other relay device and. to complete certain circuits through the energized position of the corresponding relay device and the normal deenergized posit-ion of the remaining relay device.

v12. In a system of vehicle c-ontrohthe combination with a dynamo-electric machine, of means upon the vehicle comprising a controller for effecting operationotf said machine, and means for alternatively operating the vehicle comprising a switching device upon the vehicle and a controller located'outsidethe vehicle,

13. In a system of vehicle control, the combination with a dynamo-electric machine, of means upon the vehicle comprising a controller and a revcrser for effecting operation of said machine, and means for alternatively operatingthe vehicle comprising a cut-out switch upon the vehicle and a controllerlocated outside the vehicle.

14. In a system of vehicle control, the combination with a dynamo-electric machine, of a plurality of supply conductors of dilierenteloctrical characteristics, an auxiliary conductor, means located upon the vchicle for connecting said auxiliary conductor to the one or the other supply conductor to ei'lect different operations of the machine, and alternative means having switching devices located within and without the vehicle for effecting similar connections of said auxiliary conductor to effect corresponding operation of the machine.

15. In a system of vehicle control, the combination with a dynamo-electric machine, of a plurality of supply conductors of opposite polarities, an auxiliary conduc tor, means located upon the vehicle compris ing a reverser for-energizing said auxiliary conductor from the one or the other supply conductor to determine the direction of operation of said machine, and alternative means comprising a cutout switch upon the vehicle, and a controller outside the vehicle for effecting similar energization of said auxiliary conductor to effect corresponding operation of the machine.

16. In a system of vehicle control, the combination with a dynamo-electric machine, ot a plurality of supply conductors of opposite polarities, an auxiliary conductor,

-means located upon the vehicle comprising a reverser to be thrown in the one or the other direction to etlect energization of said auxiliary conductor from the one or the other supply conductor for determining the direction oi operation of said machine and also comprising a multi-position controller for effecting operation of the machine, and alternative means comprising a cutout switch uponthc vehicle and. a controller outside the vehicle for effecting similar energization of said auxiliary coiuluctor to immediately effect corres wnding directional operation of: said machine while said reverser and said controller-occupy iimperative positions.

17. In a system of vehicle control, the combination with a dynamo-electric machine, of a 'ilumlity of relay devices for respectively controlling the forward or reverse operation of saidmachine, a plurality of supply conductors of opposite polarities, an auxiliary conductor connected to one terminal of the actuating circuits for. said relay devices, means upon the vehicle comprising a reversing-controller for said machine for energizing said auxiliary conductor from the one or the other of said supply conductors to actuate the corresponding relay device and inaugurate the corresponding vehicle operation, and alternative means comprising a cutout switch upon the vehicle and a controller outside the vehicle for effecting similar energization of said auxiliary conductor to immediately efi'ect actuation of the corresponding relay device and the corresponding directional operation of said machine while said reversing-controller occupies aninoperative position.

18. In a system of vehicle control, the combination with a dynamo-electric machine, of means upon the vehicle comprising a multi-position controller for efi'ecting complete operation of said machine, and alternative meansfor automatically operating the machine to a certain stage comprising a switching device upon the vehicle and a controller located outside the vehicle.

19,111 a system of vehicle control, the combination with an electric motor, of means upon the vehicle comprising a multi-position controller and a reverser for effecting complete acceleration of said machine, and alternative means for automatically operating said machine to a certain stage comprislng a cutout switch upon the vehicle and a controller located outside the vehicle.

. other supply conductor to determine the direction of operation of said machine and to effect combined automatic and manual acceleration of the machine, and alternative means comprising a cutout switch upon the vehicle and a controller outside the vehicle for eflecting similar energization of said auxiliary conductor to-efiect automatic acceleration of said machine in a corresponding direction to a certain stage.

In testimony whereof, I have hereunto subscribed my name this 29th day of May, 1919.

HOWARD H. JOHNSTON.

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