US1321484A - Control system - Google Patents

Description

K. A. SIMMON.

// AI f7 f2? F0" 14 I A I Patented Nov. 11, 1919.

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UNITED STATES PATENT OFFICE.

KARL A. SIMMON, OF EDGEWOOD PARK, PENNSYLVANIA, ASSIGNOR TO WESTINGHOUSE ELECTRIC AND MANUFACTURING COMPANY, A CORPORATION OF PENNSYLVANIA.

CONTROL SYSTEM.

Specification of Letters Patent.

Patented Nov. 11, 1919.

Application filed. July 3, 1916. Serial No. 107,263.

To all whom it may concern:

Beit known that I, KARL A. SIMMoN, 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 Control Systems, of which the following is a specification.

My invention relates to systems of control for electric motors and particularly to control systems of the so-oalled field-control type for controlling vehicle-propelling motors.

One object of my invention is to provide a control system of the above indicated character which shall be simple to construct and etficient in operation and which shall be provided with a multiple number of fieldcontrol operative positions.

Another object of my invention is to provide a control system of the above indicated character with means for preventing the operation of the controller when an excessive amount of current is flowing through the motors thereof.

A further object of my invention is to provide a system having motors provided with field windings disposed in series-connected sections so that the so-called field control may be effected by a minimum number of switches.

In the accompanying drawing Figure 1 is a diagrammatic view of a control system constructed in accordance with my invention; Fig. 2 is a diagrammatic view of the disposition of the field-winding sections upon the motor pole pieces; Fig.3 is a diagrammatic view of a modification of my invention; Fig. 4 is a diagrammatic view of the control circuits for operating the magnets illustrated in Fig. 1, and Fig. 5 is a control chart illustrating the sequence of operation of the switches in Fig. 1.

Referring to Fig. 1 of the drawing, motors 1, 2, 3 and 4, respectively having armatures A1, A2, A3 and A 1 and field-winding sections F1 to F3, F 1 to F6, F7 to F9 and F10 to F12. are adapted to be controlled and to be connected across supply conductors t and g by means of switches LS, R, M, G, R and 5 to 10. A limit magnet LM, which is insertcd in the circuit of the motor 1, is adapted to engage a star wheel 11 mounted upon trolled by the switch R, is initially in circuit with the motors. The field-winding sections F1 to F3 and field-winding sections F4 to F6 are respectively provided with permanent connections 13, 14 and 15, and the field-wind ing sections F7 to F9 and field-winding sections F10 to F12 are respectively provided with permanent connections 16, 17 and 18. In Fig. 2 of the drawing, the field-winding sections F1 to F3 are mounted upon field pole pieces 19, 20, 21 and 22.

The master controller MG comprises a movable contact segment 23 which is adapted to engage contact fingers 24: to 35 for closing circuits from a battery B through the coils of the switches LS, JR, M, G, R and 5 to 10 when moved to positions ato h.

The system illustrated in Fig. 1 may be accelerated through four series-parallel positions and four parallel positions by moving the master controller successively through its positions a, b, 0, (Z, a, f, g and h.

'VVh'en the master controller is moved to position a, the movable contact segment 23 engages contact fingers 24, 25, 26, 30 and 33 to close circuits through the coils ct the switches LS, JR, 5 and S. The switches LS, JR, 5 and 8 are operated to complete a circuit from the trolley conductor 25 through switch LS and resistor 0", where the circuit divides, one branch extending through the motor 2 to the switch 5 and the other branch extending through the coil of the limit magnet LM and the motor 1 to the switch 5 and then through the switch JR, the motors 3 and A, in parallel, and the switch 8 to the ground conductor g. The motors are thus connected in seriesparallel-circuit relation across the supply conductors t and g. In position Z) of the master controller, the switch R is operated to exclude the resistor 1" from the circuit of the motors. In position 0, the switches 5 and 8 are released and the switches 6 and 9 are operated to egicliide the fieldwinding sections F3, F6, F9, and F12fr'om the circuit the motors, and, in position :2;

the switches G and 9 are released and the switches 7 and 10 are operated to exclude the field-winding sections F2, F5, F8 and F11 from the circuit of the motors. Between positions (Z and c of the master controller, the switches It, 7 and 10 are released and the switches G, 5 and 8 are operated to effect a transition of the motors from seriesparallel relation to parallel relation.

In position 0, which is the first parallel position of the motors, the switch J It is released, and the switch M is operated to cornplete a circuit across the supply conductors t and g which may be traced from conduc tor it through the line switch LS, resistor 9' and the motors 1, 2, 3 and 4, in parallel, to the ground conductor g. In position 7, the switch R is operated to short circuit the resistor r. In position 9, the switches 5 and 8 are released and the switches 6 and 9 are operated to exclude the fieldwinding sections F3, F6, F9, and F12 from the motor circuit and in position h, which is the full-parallel position of the motors, the switches 6 and 9 are released, and the switches 7 and 10 are operated to exclude the field-winding sections F2, F5, F8 and F11 -from the circuit of the motors.

It may be noted, by reference to Fig. 2 of the drawing, that each of the field-winding sections F1, F2 and F3 has a portion located upon each of the pole pieces 19 to 22. As shown in Fig. 1 of the drawing, the field-winding sections F1 to F3 and field-winding sections F4: to F6 are provided with permanent connections 13 to 15, whereby the field-winding sections F3 and F6 may be short circuited by the switch 6 and fieldwinding sections F2 and F5 may be short circuited by the switch 7. The field-winding sections F7 to F 9 and fieldwinding sections F10 to F12 are provided with the permanent connections 16 to 18, whereby the field-winding sections F9 and F12 may be short circuited by the switch 9 and the field-winding sections F8 and F11 may be short circuited by the switch 10.

The limit magnet LM, which is inserted in the circuit of the motor 1, is provided wit-h a magnet core 11a that is adapted to engage the teeth of the star wheel 11 to prevent further operation of the master con troller whenever an excessive current is flowing through the motors.

In Fig. 3 of the drawing is shown a diagrammatic view of a portion of a modified system which embodies balancing resistors in the permanent connections between the various field-winding sections. The permanent connections 13 and 1 1 only are shown as provided with balancing resistors but it is to be understood that all the permanent connections 13 to 18 may be pro vided with balancing resistors 12. The switches 5 to 10 are connected to central taps in the resistors 1'2, as indicated in Fig. 2 ot the drawing. In the case of large inotors, the balancing resistors are adapted to prevent the unbalan'cing of the field-winding sections.

Although I have illustrated my invention by motors having four pole pieces and field windings divided into three series-con nected sections, it is to be understood that my invention may be applied to a control system having motors provided with any number of pole pieces and any number of field-winding sections.

Various modifications in the circuit connections and arrangement of controller positions may be efifected within the spirit and scope of my invention, and, I desire, there fore, that only such limitations shall be imposed as are indicated in the appended claims.

I claim as my invention:

1. In a system of control, the combination with a supply circuit, a plurality of motors having armature and field windings and initially connected in series-parallel-ciri-uit relation across the supply circuit, the field winding of each motor comprising a plurality of field coils and divided into a number of series-connected sections each of which has a portion thereof included in each field coil, and permanent connections in each series parallel motor circuit between like field-winding sections, of means for varying the number of field-winding sections included in the motor circuit.

2. I11 a system of control, the combination with a supply circuit, and a plurality of motors initially connected in series-parallel-circuit relation across the supply circuit, each of said motors having a field winding composed of series-connected sections and the motors initially connected in parallel having permanent connections between the field-winding sections, of means comprising a switch connected to each of said permanent connections between field-winding sections for successively excluding said sections from the motor circuit.

3. In a system of control, the combination with a supply circuit, two dynamoelectric machines connected in parallel-circuit relation across the supply circuit, each of said machines having field windings composed of a number of series-connected sections, and permanent connections between like field-winding sections, of means comprising a switch connected to each of said permanent connection for successively excluding said field-winding sections from the circuit of the dynamo-electric machines.

4. In a system of control, a plurality of motors connected in parallel pairs, said motors having armature windings and field windings disposed in sections, each field- Winding section surrounding the armature winding cooperating therewith, and permanent connections between the field-winding sections of each pair of motors.

5. In a system of control, the combination with a supply circuit, a plurality of motors connected in parallel pairs, said motors having armature windings and field windings composed of series-connected sections, each field-winding section surrounding the armature winding cooperating therewith, and permanent connections between the field-winding sections of each pair of motors, of means comprising a switch connected to each of said permanent connections for successively excluding the fieldwinding sections in pairs from the motor circuit.

6. In a system of control, the combination with a supply circuit, a plurality of motors connected in parallel pairs, said motors having armature windings and field windings composed of sections, each field-winding section surrounding the armature winding cooperating therewith, and permanent connections between the field-winding sections of each pair of motors, of means comprising a switch connected to each of said permanent connections for successively excluding the field-winding sections in pairs from the motor circuit, and means for connecting the motors 'in series-parallel and in parallel-circuit relation acros the supply circuit.

7. In a system of control, the combination with a supply circuit, a plurality of motors having armature and field windings initially connected in series-parallel-circuit relation across the supply circuit, the field winding of each motor comprising a plurality of coils and divided into a number of series-connected sections each of which has a. portion thereof included in each field coil, and permanent connections comprising balancing resistors in each seriesparallcl motor circuit between like field-winding sections, of means for varying the number of field-winding sections included in the motor circuit.

8. In a system of control, the combination with a supply circuit, two dynamo-electric machines connected in parallel-circuit relation across the supply circuit, each of said machines having field-windings composed of a number of series-connected sections and permanent connections comprising balancing resistors between like fieldwinding sections, of means comprising a switch connected to each of said balancing resistors for successively excluding said field-winding sections from the circuit of the dynamo-electric machines.

9. In a ystem of control, the combination with a supply circuit and a plurality of motors severally having armatures and series-connected plural section field windings, of permanent connections between the ends of each set of corresponding sections that are remote from the armatures, and means for varying the number of fieldwinding sections included in the motor circuit.

10. In a system of control, the combination with a supply circuit and a plurality of motor severally having armatures and series-connected plural-section field windings, of permanent connections between corresponding sections, and means comprising a switch connected to each of said permanent connections for successively excluding the sets of corresponding field-winding sections from circuit.

11. In a system of control, a pair of motors connected in parallel relation and severally having armature windings and plural-section field windings, each section surrounding th armature winding cooperating therewith, and permanent connections between the corresponding field-winding sections.

12. In a system of control, a pair of motor connected in parallel relation and severally having armature windings and KARL A. SIMMON.

Copies 0! this patent may be obtained for five cents each, by addressing the "Commissioner of Patents, Wuhington, D. 0.

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