US1381277A - Control system - Google Patents

Description

AQH. CANDEE AND H. H. JOHNSTON.

CONTROL SYSTEM. APPLICATION Huzu' AUG-7,1916.

1 $381,277. Patented June 14, 1921.,

Z SHEETS-SHEET I. t 02E EH4 Al F/ WITNESSES 1 lNVENTOR Andrew H. [ans/ea g in A. H. CANDEE AND H. H. JOHNSTON. 00 111101 SYSTEM. APPLICATION FILED AUG-7. 1916.

1,381,277. PatentedJune 14,1921.

2 SHEETSSHEET 2.

UNITED sures PATENT OFFICZE.

ANDFIEW H. GANDEE, OF PITTSBURGH,

AND HARVEY H. JOHNSTON, PENNSYLVANIA, ASSIGNORS TO WESTINGHOUSE ELECTRIC AND OF EDG-EWOOD, MANUFACTUR- ING- COMPANY, A CORPORATION OF PENN SYLVANIA.

CONTROL SYSTEM.

Specification of Letters Patent.

Application filed August 7, 1916. Serial No. 113,481.

To all whom it may concern Be it known that we, ANDREW H. Simon, 7

a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, and HARVEY H. JOHNSTON, a citizen of the United States, and a resident of Edgewood, in the county of Allegheny and State of Pennsylvania, have invented a new and use ful Improvement in Control. Systems of which the following is a specification.

Our invention relates to systems of control for-electric vehicles and particularly to systems wherein the motors are adapted to be, connected to a supply circuit in series and in parallel-circuit relation.

One object of our invention is to provide a system of the above indicated class that shall effect the transition of the motors from series to parallel-circuit relation with a minimum number of switches and with substantially no decrease in the torque supplied by the motors.

Another object of our invention is to provide a system wherein the transition of the motors from series toparallel-circuit relation may be effected with a, minimum amount of arcing at the switches and wherein the current flow through one of the motors is reversed.

A further object of our invention is to provide a system having anumber of resistors and circuit connections so disposed that themotors may be accelerated by a minimum number of. switches.

More specifically, our-invention consists of a control system provided with three motors initially connectedin series with a number of resistors to a supply circuit. A minimum number of switches is provided for ex cluding the resistors in sequence from the motor circuit and for placing the resistors in parallel in the motor circuit, and two switches are provided for. effecting the transitionof the motors from series to parallel-circuit relation.-

.In the accompanying. drawings illustrate.

ing our 'inventiornFigure 1 is a diagrammatic view of a control system constructed inaccordance with our invention; Fig. .2 1s

a diagrammatic view of the control circuits for governing the operation of the switches shown in Fig.1; Fig.3 is a control chart disclosing the, sequence of operation of the switches shown in Fig. 1; Figs. 4, 5, 5, 6 and are diagrammatic views illustrating the circuits formed through the motors shown in Fig. 1; Fig. 8 is a diagrammatic View of a modification of our invention; Fig. 9 is a diagrammatic View of thecontrol circuits for governing the operation of the switches disclosed in Fig. 8; Fig. 10 is a control chart disclosing the sequence of operation of the switches in Fig. 8, and Figs. 11 to 19, inclusive, are diagrammatic views of the circuits formed through the motors shown in FilgN. 8. e

eferring to Fig. 1 of the drawings, mo-

tors 1, 2 and 3, respectively comprising armatures A1, A2 and A3 and field windings F1, F2 and F3, are adapted to be connected in series with resistors T1 and r2 across a supply circuit comprising a trolley conductor 23 and a ground conductor 9 and to be controlled by means of unit switches R1 to R4, inclusive, and P, S and G. a

Referring to F i .2 of the drawings, a master controller C, having a movable contact segment 4, is adapted to be moved through positions 1 to 7, inclusive, to engage contact fingers 5 to 12, inclusive, and

complete circuits from a batteiiy B through the coils of the switches R1 to and S, P and G. r

In Fig. 8 of the drawings, three motors 14, 15 and 16, respectively comprising armatures A4, A5 and A6 and field windings F4, F5 and F6, are adapted to be connected, with resistors r3, T4 and 15, across a supply circuit comprising a trolley conductor t1 and a ground conductor 91 and to be controlled by means of the unit switches R5 to R8, inclusive, and S1, P1 the drawings, a master controller M61, having a movable contact segment 17, is adapted to engage stationary contact fingers 18 to 25, inclusive, when moved through positions 1 to 10, inclusive, and complete circuits from a battery Bl through the coils of the switches R5 P1 and G1.

The operation of the system disclosed in Figs. 1 to 7 ,inclusive, when the master controller is moved through positions 1 to 7, inclusive, is as follows. controller MO is moved to position 1, the movable contact segment 4 engages the contact fingers 5, 6 and 10 to complete circuits and G1. In Fi 9 of to R8, inclusive, and S1,

When the master inclusive,

from the battery B through the coils of the switches R1 and S. The switches H1 and S are operated to complete a circuit which may be traced from the trolley conductor 16 through the switch R1, resistors 11 and r2, switch S and the motors 1, 2 and 3 in series to the ground conductor 9, as illustrated in Fig. 4 of the drawings.

In position 2 01 the master controller, the switch R1 is released and the switch R2 is operated to complete a circuit from the trolley conductor t through the resistor 92 and the motors 1, 2 and 8 in series to the ground. conductor 9, as illustrated in Fig. 5 of the drawings. In position 3 of the master controller, the switch is operated to place the resistors T1 and T2 in parallel in the motor circuit, as shown in Fig. 5 In position 1-. of the master controller, the switch R1 is operated to exclude the resisters T1 and r2 from the motor circuit, as will be understood without further illustration.

lVhen the master controller is moved to position 5, which is the first parallel position of the motors, the switches R1 and R3 are released and the switches P and (i are operated to complete a circuit which may be traced from the trolley conductor t through the switch F2 and the resistor r, where the circuit divides, one branch extending through the switch S, motor 1 and the switch G to the grpund conductor 9 and a second branch extending through the switch F and through the motors 2 and 3 in parallel to the ground conductor 9. The circuit thus traced is disclosed in. Fig. 6 of the drawings. In position. 6 of the master controller, the switch R3 is operated to place the two resistorsfrl and T2 in parallel. in the motor circuit, similarly to the arrangement shown in Fig. 5. In position 7 of themaster controller, which is the full-parallel position, the switches R1 and R4 are operated to e);- cludethe resistors 71 and r2 from the motor circuit, as illustrated in Fig. 7 of the drawings.

The system disclosed in Figs. 8 to 19, inclusive,.may be operated through five series and five parallel positions by the controller contained therein, as follows: When the master controller is moved to position 1, the contact segment 17 engages contact [ ingers 18, 19 and 23 to complete circuits from the battery I31 through the coils oi the switches R5 and S1. The switches B5 and $1 are operated to complete a circuit through the motors 14, 15 and 16 which may be traced from the trolley conductor 61 through the switch R5, resistors r3, M and r5, switch S1 and the motors 14, 15 and 16 in series to the ground conductor'gl, as illustrated in F ig.. 11 oi: the drawings. In position 2 of the master controller, the switch R5 is released and the switch R6 is operated to excludethe resistors T3 and M from the motor circuit, as illustrated in Fig. 12 01' the drawings. In position 3 of the master controller, the switch R7 is operated to place the re sistors T3 and M: in parallel with the resistor T5 in the motor circuit, similarly to the arrangement shown in Fig. 16. In position 1 of the master controller, the switch R7 is released and the switch R8 is operated to ex clude the resistor r3 from the motor circuit and to place the resistors W1 and T5 in parallel in the motor circuit, as illustrated in Fig. 13 of the drawings. In position 5 of the. master controller, which is the full-series position, the switch. R8 released and switches R5 and R7 are operated to exclude the resistors r3, "1' 1 and 1 5 from .the motor circuit, as illustrated in Fig; 1 1 of the:

drawings.

When the master controllerv is moved to position 6, which is the. first parallel position, the switches R5 and R7 'are released and the switches P1 and. G1 are operated to complete a circuit in parallel through the motors 1 1 to 16, inclusive, which maybe traced from the trolley conductor 61 through the switch. R6, resistor r5, where the circuit divides, one branch extendingthrough. the switch S1, motor 1a and the switch. G1 to the ground conductor 1 and. the: other branch extending through the switch P1 and the motors 15 and 16 in parallel to the ground conductor 1, as illustrated in Fig. 15 of the drawings. In position 7 of the. master controller, the switch R7 is operated to place the resistors T3 and M: in parallel with the resistor T5 in the motor circuit, as illustrated in Fig. 16 of the drawings. In position 8 of: the master: controller, the switch R7 is released and the switch R8 is operated to exclude the resistor r3 from the motor circuit and to insert the resistors T4; and r5 in parallel therein, as illustrated-in Fig. 17 of the drawings. In position 9 of the master controller, the switch R5 is operated to include the resistor r3 in parallel with resistors W1 and T5 in the motorcircuit, as illustrated in Fig. 18 of the drawings, and in position 10 of the master con troller, which is the full-parallel position, the switch R7 is operated to exclude the resistors r3, 1 a and 1 5 from the'motor circuit, as illustrated in Fig. 19 of the drawings.

In the two systems above described, particular attentionis called to the fact that the three motors, included in either system, are connected in series across the supply circuit when one switch is operated and that the motors may be changed from series to parallel-circuit relation by the simultaneous. operation of two switches which need notbe interlocked with any other switches; Fur.- thermore, there is substantially no decrease in the torque of the motors during the :transi-. tion. Attention is also directed to the-fact that the current is reversed through the motor 2 in Fig. 1 and the motor 15 in Fig. 8 of the drawings during transition.

In order to simplify the disclosure, no reversing means has been illustrated in connection with the motors, but it is to be understood that any well known means for reversing the motors may be applied to the systems disclosed.

Various modifications in the circuit connections and the arrangement of the controller positions may be efiected within the spirit and scope of our invention, and we desire, therefore, that only such limitations shall be imposed as are indicated in the appended claims.

We claim as our invention:

1. In a system of control, the combination with a supply circuit and three motors initially connected in series-circuit relation thereto, of means for effecting the transition of said motors from series to parallelcircuit relation with substantially no decrease in the torque supplied thereby.

2. In a system of control, the combination with a supply circuit and three motors initially connected in series-circuit relation thereto, of two switches for effecting a transition of said motors from series to parallel-circuit relation with substantially no decrease in the torque supplied by said motors.

3. A method of control for a three-motor equipment which consists in connecting the motor in series-circuit relation, accelerating the motors in series-circuit relation, effecting a transition of said motors from series to parallel-circuit relation while reversing the current flow through one of the motors and accelerating the motors while connected in parallel-circuit relation.

4:- In a system of control, the combination with a supply circuit, two resistors, and three motors initially connected in series through said resistors to the supply circuit, of a plurality of switches for excluding said resistors from the motor circuit and for placing said resistors in parallel in the motor circuit, and means for effecting the transition of said motors from series to parallel-circuit relation.

5. In a system of control, the combination with a supply circuit, two resistors and three motors initially connected in series through said resistors to the supply circuit, of four switches for excluding said resistors from the motor circuit and for placing the resistors in parallel in the motor circuit, and two switches for effecting the transition of said motors from series to parallelcircuit relation.

In testimony whereof, we have hereunto subscribed our names this 14th day of July,

ANDREW H. CANDEE. HARVEY H. JOHNSTON.

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