JPH10247443A - Closing spring energy storing motor control circuit for circuit breaker spring operating apparatus - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a closing spring energy storing motor control circuit for a circuit breaker spring operating apparatus in which the starting of a closing spring energy storing motor and the stopping accompanied with the dynamic braking can be conducted by using only one electromagnetic contactor. SOLUTION: An electromagnetic contactor Mc which is excited when a limit switch LS detecting the operation of a closing spring detects the energy storing of the closing spring and is closed is provided. The normally open contact mca1 of the electromagnetic contactor is connected between a field winding Fc and an armature winding Ac, and a normally open contacts mca2, mca3 are connected between both ends of the series circuit of both windings Fc, Ac and a power supply. Both ends of the armature winding Ac are connected to both ends of the field winding Fc through the series circuit of the normally closed contact mcb1 of the same electromagnetic contactor and a current limiting resistor R and the normally closed contact mcb2, and a braking circuit is formed by connecting the armature winding Ac and the field winding Fc in series when the electromagnetic contactor is not excited.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control circuit for an electric motor used as a drive source for an energy storage mechanism of a closing spring in a spring operating device for operating a power circuit breaker.

[0002]

2. Description of the Related Art As an operating device for operating a circuit breaker, a closing operation of a circuit breaker is performed by using a closing spring stored by a DC motor and a blocking spring stored when releasing the closing spring. There is one that performs a shut-off operation.

FIGS. 2 and 3 show an example of this type of circuit breaker operating device. FIG. 2 shows a state in which the operation of closing the circuit breaker has been completed, and FIG. 3 shows the operation of breaking the circuit breaker. This shows a completed state.

In FIGS. 2 and 3, reference numeral 1 denotes a closing spring mounted on the main frame 2A of the operating device, and reference numeral 3 denotes a blocking spring mounted on the main frame 2A. The closing spring 1 has a coil spring 7 disposed between a movable plate 5 slidably provided in a cylinder 4 and a spring receiving plate 6 disposed at a rear end of the cylinder 4. A plunger rod 8 is attached. One end of a traction link 9 arranged substantially along the center axis of the coil spring 7 is connected to a rear end of the plunger rod 8 via a pin 10. A stopper 11 that abuts the movable plate 5 is attached inside the tip of the cylinder 4.

[0005] A DC motor 12 and a gear reduction mechanism 13 for reducing the rotation of the DC motor 12 are mounted on an auxiliary frame 2 B fixed to the frame 2. An arc-shaped long hole 15 extending in the circumferential direction of the gear 14 is formed in the last stage gear 14 of the speed reduction mechanism 13.
6 are fitted. One end of a link 17 is fixed to the pin 16, and the other end of the link 17 is a lever 19 rotatably supported by a shaft 18 attached to the auxiliary frame 2B.
Is connected to one end via a pin 20. Lever 19
A pin 21 is attached to the other end of the traction link 9, and the pin 21 is fitted in a long hole 9 a formed in the other end of the traction link 9. In this example, the speed reduction mechanism 13, the pin 16, the link 1
7, the lever 19, the pins 20, 21 and the traction link 9 constitute a closing spring accumulation mechanism 22.

A slider 8 is provided at the tip of the plunger rod 8.
a, and the slider 8a is mounted on the main frame 2A.
Are slidably fitted in and guided by the guide grooves 23 formed in the guide groove 23.

The tip of the plunger rod 8 is also connected to a closing hacker 25 via a link mechanism 24, and the urging force of the closing spring 7 is applied to the closing hacker 25 via the link mechanism 24.
, And the closing spring 7 is held in the charged state in preparation for the closing operation. In this example,
The link mechanism 24 and the closing hacker 25 hold the closing spring in the charged state in preparation for closing of the circuit breaker, and the closing hacker mechanism 26 for releasing the closing spring when closing the circuit breaker.
Is configured.

The blocking spring 3 has a coil spring 32 disposed between a movable plate 30 slidably provided in a cylinder 29 and a spring receiving plate 31 disposed at the rear end of the cylinder 29. A plunger rod 33 is attached to the movable plate 30, and a stopper 34 that abuts the movable plate 30 is attached inside the tip of the cylinder 29.

One end of a link 36 is connected to the tip 33a of the plunger rod 33 via a pin 35, and the link 3
The other end of 6 is connected via a pin 39 to one end of a V-shaped lever 38 attached to an output shaft 37 rotatably supported by the main frame 2A. The other end of the lever 38 is connected to one end of a link 41 via a pin 40,
The other end of 1 is connected to one end of a link 43 via a pin 42. The other end of the link 43 has a slider 44 with a pin 4
The slider 44 is slidably fitted in the guide groove 23.

A lock lever 46 for locking a pin 42 connecting the links 41 and 43 is rotatably supported on the main frame 2A, and the pin 42 is provided with a notch 46a ( (See FIG. 3), so that the blocking spring 3 is held in an energized state.

The pin 42 is also connected to one end of a link 47, and the other end of the link 47 is connected to a trip hacker 49 via a link mechanism 48. A pin 50 connecting the link mechanism 48 and the link 47 is fitted and guided in a groove 51 formed in the main frame 2A.

At the end of the blocking spring 3, a shock absorber 52 for reducing the impact when the movable plate 30 abuts against the stopper 34 at the tip of the cylinder is attached, and a plunger rod 33 is connected to the shaft of the shock absorber 52. I have.

In the illustrated example, when the closing spring 1 is released by the plunger rod 33, the link 36, the lever 38, the links 41, 43 and the slider 44, the breaker is closed on the output shaft 37 by the urging force of the closing spring. A spring storing / loading mechanism 53 is provided to provide an operating force for the operation and to store the blocking spring 3.

The link spring 47, the locking lever 46, the link mechanism 48, and the tripping hacker 49 hold the shut-off spring 3 in a charged state in preparation for tripping the breaker. Hacker mechanism for tripping 5
4 are configured.

The output shaft 37 is connected to an operating shaft for operating a movable contact of a circuit breaker (not shown), and the circuit breaker is turned on when the output shaft 37 rotates a predetermined angle in a counterclockwise direction in the drawing. The circuit breaker is opened by rotating the shaft 38 by a certain angle clockwise in the drawing.

In the above-mentioned spring operating device, when the closing operation of the circuit breaker is completed, each part is in a state shown in FIG. 2, and the coil spring 7 and the breaking spring 3 constituting the closing spring 1 are formed.
Is in a compressed state. When a shutoff command is given in this state, the tripping hacker 49 composed of a half-moon-shaped lever is rotated clockwise in the drawing. As a result, the link mechanism 48 is deformed and the pin 42 is removed from the notch 46a of the locking lever 46, so that the coil spring 32 constituting the blocking spring 3 is released (the coil spring 32 is extended) and the lever 38 Rotate clockwise. Since the output shaft 37 is rotated clockwise by the rotation of the lever 38, the movable contact of the circuit breaker (not shown) is pulled off from the fixed contact, and the breaking operation is performed. When the cutoff operation is completed, the state shown in FIG.
The slider 44 attached to the abutment 3 comes into contact with the slider 8a at the tip of the plunger rod 8 urged by the closing spring. The deformed link mechanism 48 and the tripper hacker 4
9 returns to the original state by the action of the return springs 55 and 56.

When a command to turn on the circuit breaker is given in the state of FIG. 3, the closing hacker 25 is rotated counterclockwise in the drawing, whereby the link mechanism 24 is deformed and the closing spring 1 is released. Can be At this time, since the coil spring 7 constituting the closing spring 1 is extended, the flanger rod 8 pushes the link 43 to rotate the lever 38 counterclockwise in the drawing, and rotates the output shaft 37 counterclockwise to close the circuit breaker. At the same time, the coil spring 32 is compressed and the cut-off spring 3 is charged. When the charging of the blocking spring is completed, the pin 42 engages with the notch 46a of the locking lever 46 to hold the blocking spring 3 in the charged state. When the release of the closing spring 1 is completed, the movable plate 5 comes into contact with the stopper 11 as shown in FIG. If the movable plate 5 is not finally displaced to the position where it comes into contact with the stopper 11 when the closing spring is released, the closing operation stroke may be insufficient and the closing of the circuit breaker may be incomplete. Therefore, in this type of operating device, when the release of the closing spring is completed, the lever 1
9 is attached to the elongated hole 9a of the towing rod 9
The dimensions of each part are set so as to stop at a position with a margin before the rear end 9a1.

When the release of the closing spring 1 is detected by the limit switch LS detecting the movement of the closing hacker mechanism, the DC motor 12 is started, and the gear 14 is rotated counterclockwise in the drawing. . In the course of the rotation of the gear 14, when the rear end 15a of the circular arc-shaped long hole 15 provided in the gear 14 in the rotating direction comes into contact with the pin 16, the link 17
The lever 19 is rotated counterclockwise through the lever. When the pin 21 abuts on the rear end 9a1 of the elongated hole 9a after the lever 19 starts rotating, the towing rod 9 is towed leftward in the drawing with the rotation of the lever 19, so that the movable plate 5 Moves to the rear end side of the cylinder 4 to compress the coil spring 7 constituting the closing spring 1. When the charging operation of the closing spring is completed, the closing hacker 25 returns to the original position, and the closing spring 1 is held in the charged state. Further, after the accumulation of the closing spring 1 is completed, as shown in FIG. 5, when the pin 20 and the pin 16 and the rotating shaft 14a of the final stage gear 14 exceed a dead point where they are aligned, the lever 19 is released. The pin 16 is rotated by the action of a return spring (not shown)
Is moved in the slot 15 in a counterclockwise direction in the drawing at a speed higher than the rotation speed. As a result, the pin 16 is
5 is separated from the rear end 15a of the motor 1,
2 does not receive the driving force. Thereafter, the electric motor 12 is disconnected from the power source, and the final gear 14 stops with the pin 16 positioned at the intermediate portion of the elongated hole 15 as shown in FIG.

As described above, the DC motor 12 for accumulating the closing spring 1 is in a state in which the pin 20, the pin 16, and the rotating shaft 14a of the final gear 14 are aligned after the closing spring has been charged. After the dead point is exceeded, the motor 12 is disconnected from the power supply and stopped, but the motor 12 continues to rotate by inertia even after disconnection from the power supply, and the motor 12
The elongate hole 15 keeps rotating while keeps rotating. In this case, if the motor stops before the rear end portion 15a of the long hole 15 comes into contact with the pin 16, no particular problem occurs.
When the rear end 15a of the 5 comes into contact with the pin 16 to slightly rotate the lever 19, the pin 21 fitted in the elongated hole 9a provided in the towing rod 9 is moved from its normal position. Also stops at a position closer to the rear end 9a1 side of the long hole 9a, so that when the closing spring 1 is released next time, the rear end of the long hole 9a as shown in FIG. The portion 9a1 abuts on the pin 21 to prevent the closing spring 1 from being completely released, and the movable plate 5 stops before the stopper 11.
When such a state occurs, the closing stroke of the circuit breaker is insufficient, so that the closing of the circuit breaker may be incomplete.

In order to prevent such a problem from occurring,
After the DC motor 12 is disconnected from the power supply, excessive braking of the motor is prevented by applying dynamic braking to the motor. In the conventional breaker spring operating device, when the electric motor 12 is subjected to the dynamic braking, the drive of the electric motor 12 is started when it is detected that the closing of the closing spring 1 is completed. The control circuit of the motor 12 is configured such that when the completion is detected, the motor 12 is disconnected from the power supply, and the field winding and the armature winding of the motor 12 are short-circuited to form a dynamic braking circuit. Was.

As this type of control circuit, there is
As disclosed in Japanese Patent No. 0280, an armature having a normally open contact for opening and closing between an armature winding and a power supply and a normally closed contact for short-circuiting both ends of the armature winding to form a braking circuit. A magnetic field comprising a magnetic contactor for winding control, a normally open contact for opening and closing between the field winding and a power supply, and a normally closed contact for short-circuiting both ends of the field winding to form a braking circuit. An armature winding and a field winding are provided by providing two electromagnetic contactors with a winding control electromagnetic contactor and exciting these electromagnetic contactors when it is detected that the closing spring has been completely released. By connecting the wire to the power supply and rotating the motor, when it is detected that the charging of the closing spring has been completed, both electromagnetic contactors are de-energized, so that both ends of the armature winding and the field winding are connected. It is known that the motors are short-circuited to apply dynamic braking to the motor.

[0022]

Problems to be Solved by the Invention 7-40280
In the motor control circuit disclosed in Japanese Patent Application Laid-Open Publication No. H10-209, it is necessary to use two electromagnetic contactors, an electromagnetic contactor for controlling an armature coil of the motor and an electromagnetic contactor for controlling a field winding. Therefore, there has been a problem that the structure becomes complicated and the cost increases.

An object of the present invention is to provide a spring operating device for a circuit breaker which can start and close a DC motor for storing a closing spring by using only one electromagnetic contactor and stop it together with dynamic braking. An object of the present invention is to provide a motor control circuit for storing a closing spring energy.

[0024]

As described above, in the spring operating device for a circuit breaker to which the present invention is directed, the closing spring and the breaking spring, one end of the field winding and one end of the armature winding are electrically connected. Motor that is electrically connected and operated with both windings connected in series, a closing spring charging mechanism that stores the closing spring by using the DC motor as a drive source, and closes in preparation for closing the circuit breaker A closing hacker mechanism for holding the spring in an accumulating state and releasing the closing spring when closing the breaker, and a closing hammer mechanism for closing the closing shaft to the output shaft by the biasing force of the closing spring when the closing spring is released. An interrupting spring accumulating and closing mechanism that applies an operating force and accumulates an interrupting spring, and holds the interrupting spring in an accumulating state in preparation for tripping the circuit breaker, and releases the interrupting spring when the circuit breaker is tripped And a hacker mechanism for tripping. It adapted to provide a cut-off operation force to the output shaft by the urging force of the disconnection spring.

The present invention relates to a control circuit for controlling the electric motor for accumulating the closing spring of the spring operating device for a circuit breaker as described above. In the present invention, the circuit is turned on when the closing spring is released. A limit switch that is turned off when the charging of the closing spring is completed, and an electromagnetic contactor that is excited when the limit switch is turned on.

The electromagnetic contactor has a normally open contact for switching between windings and at least one normally open contact for switching power (a contact).
And a pair of normally closed contacts (b contacts) for forming a braking circuit, and a normally open contact for switching between windings is provided between one end of the field winding of the DC motor and one end of the armature winding. The field winding and the armature winding are disconnected or connected in series by opening and closing the normally open contact. A power supply normally open contact is inserted between at least one end of the series circuit of the field winding, the inter-winding normally open contact and the armature winding and the power supply, and the power supply normally open contact is By this, the series circuit of the field winding and the armature winding is disconnected from the power supply or connected to the power supply. Further, the pair of normally closed contacts for forming a braking circuit are a circuit for connecting between one end of the field winding and the other end of the armature winding when each is closed, and the other end of the field winding and the armature A circuit for connecting between one end of the winding is provided, and when the pair of normally closed contacts for forming a braking circuit are closed together, the field winding and the armature winding are connected in parallel with each other. To form a dynamic braking circuit.

In order to limit the braking current flowing through the dynamic braking circuit, a circuit for connecting a current limiting resistor between one end of the field winding and the other end of the armature winding, It is preferable to insert a current limiting resistor in at least one of the circuits connecting between the other end and one end of the armature winding.

In the above control circuit, when the energizing of the closing coil is completed, the limit switch is turned on and the electromagnetic contactor is excited. At this time, the normally-open contact for switching between windings is closed to connect the field winding and the armature winding in series, and the normally-open contact for power switching is closed to connect the field winding and the armature winding. To connect the series circuit to the power supply, the motor is operated as a DC series motor, and the closing spring is charged.
When the charging of the closing spring is completed, the limit switch is turned off, the normally open contact for power supply opening and closing disconnects the field winding and the armature winding from the power supply, and the normally open contact for switching between windings is opened. Open to disconnect the field winding and armature winding. At this time, at the same time, the pair of normally closed contacts for forming a braking circuit is closed and the field winding and the armature winding are connected in parallel to form a closed circuit (power generation braking circuit). With the voltages induced in the armature windings, braking can be applied to the motor by passing braking through the closed circuits of both windings, and the motor can be stopped immediately after the charging of the closing spring is completed. Therefore, after the charging of the closing spring is completed, the charging mechanism of the closing spring can be prevented from being excessively displaced, and the discharging of the closing spring is prevented at the time of the next closing operation, and the closing of the closing spring is prevented. It is possible to prevent a situation where the stroke is insufficient.

As described above, according to the present invention, only by providing one electromagnetic contactor, the start-up of the closing spring accumulating motor and the stop with the power generation braking can be performed. And the cost can be reduced.

[0030]

FIG. 1 shows an example of the configuration of a motor control circuit according to the present invention. In FIG. 1, LS is turned on when the closing spring is released, and the stored energy of the closing spring is reduced. This is a limit switch that is turned off when completed. The limit switch LS detects the completion of the release operation of the closing spring 1 and the completion of the storage operation of the closing spring 1 by detecting the movement of a link leading to the trip hacker 25, for example, as shown in FIG. To be provided.

One end of the limit switch LS is connected to a line connected to the positive output terminal P of the control DC power supply (not shown), and is connected between the other end of the limit switch LS and the negative output terminal N of the control DC power supply. The excitation coil MCy of the electromagnetic contactor MC is connected. The electromagnetic contactors MC are normally open contacts (a contacts) mca1 to mca3 that open when the exciting coil MCy is in a non-excited state and close when excited.
Normally closed contacts (b contacts) mcb1 and mcb2 that close when the exciting coil MC is in a non-excited state and open when excited.
And

Fc and Ac are a field winding and an armature winding of the DC motor 12 shown in FIGS. 2 and 3, respectively.
This DC motor is a DC series motor having a large starting torque. One end f1 of the field winding Fc is connected to one end a of the armature winding Ac.
1 and is operated with both windings connected in series.

In the illustrated example, among the contacts provided on the electromagnetic contactor MC, the normally open contact mca1 is used as a normally open contact for switching between windings, and the normally open contact mca1 is used as a DC motor field. One end f1 of the magnetic winding Fc and one end a of the armature winding Ac
Connected between 1. Furthermore, normally open contacts mca2 and m
ca3 is used as a normally open contact for power supply switching, and these normally open contacts mca2 and mca3 are one end of a series circuit of a field winding Fc, an interwinding normally open contact mca1, and an armature winding Ac. (The other end f2 of the field winding Fc in the illustrated example) and the positive output terminal P of the control DC power supply, and the other end of the series circuit (the other end of the armature winding Ac in the illustrated example). a2) and the negative output terminal N of the control DC power supply.

The normally closed contacts mcb1 and mcb2 of the electromagnetic contactor MC are used as a pair of normally closed contacts for forming a braking circuit. When these normally closed contacts mcb1 and mcb2 are closed, the field A circuit that connects between one end f1 of the magnetic winding Fc and the other end a2 of the armature winding Ac, and a circuit that connects between the other end f2 of the field winding Fc and one end a1 of the armature winding Ac. It is provided to constitute a circuit.

In the illustrated example, one end of the normally closed contact mcb1 is connected to one end f1 of the field winding Fc, and the other end of the normally closed contact mcb1 is connected to the other end of the armature winding Ac through the current limiting resistor R. a2
It is connected to the. The normally closed contact mcb2 is connected to the field winding Fc.
Is connected between the other end f2 of the armature winding Ac and one end a1 of the armature winding Ac without a current limiting resistor, and when both of the pair of normally closed contacts mcb1 and mcb2 for forming the braking circuit are closed, The winding Fc and the armature winding Ac are connected in parallel with each other via a current limiting resistor R so as to form a closed loop, and a power generation braking circuit is configured.

In the control circuit shown in FIG. 1, when the release of the closing coil is completed, the limit switch LS is turned on. When the limit switch LS is turned on,
Since the exciting coil MCy of the electromagnetic contactor MC is excited,
The normally open contacts mca1, mca2 and mca3 are closed, and the normally closed contacts mcb1a and mcb2 are opened. Therefore, the field winding Fc
And an armature winding Ac are connected in series, and a DC voltage is applied from a control DC power supply to both ends of a series circuit of both windings.
As a result, the electric motor rotates, and the closing spring 1 shown in FIG.

When the charging of the closing spring 1 is completed, the limit switch LS is turned off, and the normally open contacts mca2 and mca3 for opening and closing the power supply are opened to disconnect the field winding and the armature winding from the control DC power supply. At the same time, the inter-winding switching normally open contact mca1 opens to disconnect the connection between the field winding and the armature winding. At this time, the pair of normally closed contacts mcb1 and mcb2 for forming the braking circuit are closed at the same time, so that the field winding Fc and the armature winding Ac are connected in parallel via the current limiting resistor R, A closed circuit (power generation braking circuit) of Fc-contact mcb2-armature winding Ac-current limiting resistor R-contact mcb1-field winding Fc is configured. When a closed circuit is formed in this way, a braking current flows through the closed circuit with the sum of the voltages of the same polarity induced in the field winding Fc and the armature winding Ac as the motor rotates. A large load is applied to the motor operating as a generator by the braking current. Therefore,
The electric motor 12 is braked, and the electric motor 12 is stopped quickly.

As described above, according to the present invention, the electric motor can be stopped immediately after the charging of the closing spring is completed. Therefore, after the charging of the closing spring is completed, the charging of the closing spring is completed. The mechanism can be prevented from being excessively displaced (in the example shown in FIGS. 2 and 3, the pin 21 is excessively displaced toward the rear end 9a1 side of the elongated hole 9a of the towing rod 9), and is performed next. It is possible to prevent a situation in which the release of the closing spring is hindered during the closing operation and the closing stroke is insufficient as shown in FIG.

In the above example, the current limiting resistor R is provided only in the circuit connecting between the other end a2 of the armature winding Ac and one end f1 of the field winding Fc. A current-limiting resistor is also provided in a circuit connecting between one end a1 of the field winding Fc and the other end f2 of the field winding Fc to limit the braking current by summing the resistance values of the current-limiting resistors provided in both circuits. May be set to a required value.

Further, the internal resistance of the armature winding Ac and the field winding Fc is large to some extent, and the braking current flowing through the armature winding Ac and the field winding Fc when the motor is stopped is reduced by the internal resistance of each winding. If the resistance can be limited to an allowable range, the current limiting resistor R can be omitted.

In the above example, the normally open contacts mca2 and mca2 for opening and closing the power supply are respectively connected between both ends of the series circuit of the field winding Fc, the normally open contact mca1 for opening and closing between the windings and the armature winding Ac, and the power supply. Although mca3 is provided, it is sufficient that at least one of these normally open contacts for power supply opening and closing is provided, and the normally open contact mca2 is provided.
And mca3 is omitted, and the other end f2 of the field winding Fc is omitted.
Alternatively, the other end a2 of the armature winding Ac may be directly connected to the output terminal P or N of the power supply.

[0042]

As described above, according to the present invention, the activation of the closing spring accumulating motor and the stop accompanied by the power generation braking can be performed only by providing one electromagnetic contactor. There is an advantage that cost can be reduced by simplifying the configuration of the control circuit.

[Brief description of the drawings]

FIG. 1 is a circuit diagram showing a configuration example of a closing spring accumulating electric motor control circuit according to the present invention.

FIG. 2 is a front view showing an example of a circuit breaker spring operating device in a partially cross-sectional state in which a blocking spring has completed charging and a closing spring has completed charging;

FIG. 3 is a front view of the circuit breaker spring operating device shown in FIG.

FIG. 4 is a cross-sectional view of a main part showing a state where the closing spring has completed releasing in the operating device shown in FIG. 2;

FIG. 5 is a cross-sectional view of a main part showing a state immediately before the closing spring completes energy storage in the operating device shown in FIG. 2;

FIG. 6 is a cross-sectional view of a main part showing a state when the closing spring is incompletely released in the operating device shown in FIG. 1;

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 closing spring 3 blocking spring 8 plunger rod 9 pulling rod 9a long hole 12 closing spring accumulating electric motor 13 reduction mechanism 14 last gear of reduction mechanism 15 long hole 16 pin 17 link 19 lever 21 pin 26 hacker mechanism for release 53 Breaking spring accumulating / closing mechanism 54 Hacker mechanism for tripping LS Limit switch MC Electromagnetic contactor mca1 Normally open contact for opening / closing between windings mca2, mca3 Normally open contact for power supply opening / closing mcb1, mcb2 Normally closed contact for forming braking circuit Fc Field Magnetic winding Ac Armature winding

Claims (2)

[Claims] A DC motor driven in a state in which a closing spring and a breaking spring are electrically connected to one end of a field winding and one end of an armature winding and both windings are connected in series; A closing spring accumulating mechanism for accumulating the closing spring by using the DC motor as a driving source; holding the closing spring in a charged state in preparation for closing of the breaker; releasing the closing spring when closing the breaker. A closing hacker mechanism for energizing, and an operating force for applying a circuit breaker to the output shaft by an urging force of the closing spring when the closing spring is released, and a closing spring accumulating and closing for storing the closing spring. A mechanism and a tripping hacker mechanism that holds the cut-off spring in a charged state in preparation for tripping of the circuit breaker and releases the cut-off spring when the circuit breaker is tripped, wherein the cut-off spring is When the power is released, the output shaft is blocked by the urging force of the blocking spring. In the closing spring accumulating electric motor control circuit for controlling the DC motor of the breaker spring operating device for applying the operating force, the closing spring is turned on when the spring is released, and the charging of the closing spring is completed. A limit switch that is turned off at the time, and an electromagnetic contactor that is excited when the limit switch is in the on state, wherein the electromagnetic contactor is connected to one end of a field winding of the DC motor and an armature. A normally open contact for switching between windings connected between one end of the winding, at least one end of a series circuit of the field winding, the normally open contact for switching between windings and the armature winding, and a power supply; A normally open contact for opening and closing a power supply inserted between the circuit, a circuit for connecting between one end of the field winding and the other end of the armature winding when closed, and the other end of the field winding And a circuit connecting between one end of the armature winding and And a pair of normally closed contacts for forming a braking circuit, wherein the field winding and the armature winding are connected in parallel with each other when both of the pair of normally closed contacts for forming a braking circuit are closed. An electric motor control circuit for energizing a closing spring of a breaker spring operating device, comprising a dynamic braking circuit. 2. A circuit for connecting a current limiting resistor for limiting a braking current flowing through the dynamic braking circuit between one end of the field winding and the other end of the armature winding, and the field winding. 2. The electric motor for storing a closing spring of a spring operating device for a circuit breaker according to claim 1, wherein the motor is inserted into at least one of circuits connecting between the other end of the armature winding and one end of the armature winding. Control circuit.