JP2011165644A - Electric operation device of circuit breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric operation device of a circuit breaker, which prevents the occurrence of electric corrosion in spite of being a semiconductor switch where turning on/off of a drive current of a motor is advantageous for improvement of speed and life. <P>SOLUTION: The electric operation device of a circuit breaker includes: a motor; normally-opened contacts respectively connected in series to both positive and negative power input ends of the motor and closed in driving the motor; a normally-closed contact connected in parallel to both the positive and negative power input ends of the motor and opened in driving the motor; a relay for controlling the normally-opened and normally-closed contacts; and a semiconductor switching element controlled by a signal of a limit switch following changeover of an ON/OFF signal and a condition of the circuit breaker; wherein electrical operation to the normally-opened contact in driving the motor is different from that in stopping the motor. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention relates to an electric operation device for a circuit breaker that remotely operates a handle of the circuit breaker, and more particularly to control of a motor that is a drive source of the device.

  The circuit breaker has the role of interrupting the electric circuit in order to prevent burnout of the electric wires and load equipment due to the overcurrent flowing, and operating the handle provided in this circuit breaker. It also functions as an open / close switch. This opening / closing is an electric operation device that engages with the handle of the circuit breaker in preparation for the case where the circuit breaker is installed, for example, in a deep part of the panel, although manual operation by an electric administrator is common It is also known that the circuit breaker can be operated remotely by attaching an ON signal (open to closed) or an OFF signal (closed to open) to the electrical operation device from the outside. (For example, refer to Patent Document 1).

  The remote operation of the circuit breaker is used not only to eliminate the above-mentioned “inconvenience of operation” but also to “rapid system replacement of electric circuit” in ships, for example. At that time, as is apparent from FIG. 10, in the electric operation device of Patent Document 1, the control of the motor, that is, on / off of the drive current is entrusted to the excitation of the relay and the opening and closing of the contact. In consideration of the operation time or the recovery time, there is a limit to the high-speed turning on of the electric operating device, and the contact is consumed by an arc generated at the time of opening, so that the number of opening and closing must be limited. In this respect, if the driving current is turned on and off by a semiconductor switch, it can be expected to increase its speed and life (for example, see Patent Document 2).

JP 2000-340090 (page 4, left column, line 20 to right column, line 21; FIG. 10) JP-A-3-226929 (page 3, upper left column, line 18 to lower left column, line 10, FIG. 1)

  On the other hand, as is clear from FIG. 1 of Patent Document 1, in the semiconductor switch, as shown in FIG. 10 of Patent Document 1, it is not necessary to provide contacts at both the positive and negative power supply input terminals of the motor. Due to the leakage current of the element, it is difficult to completely insulate the motor from the control power supply. For this reason, when the frame of the motor is grounded, for example, via a mechanical part, a potential difference is generated between the frame and the winding of the motor, so that particularly in a hot and humid environment, the There was a risk that the winding could corrode or break, so-called galvanic corrosion. In order to prevent this electrolytic corrosion, simply providing a contact at both the positive and negative power supply input terminals of the motor will result in a "long life" that is one of the advantages of "switching the drive current on and off with a semiconductor switch". It goes without saying that it will disappear.

  The present invention has been made to solve the above-described problems, and the on / off of the driving current of the motor is a semiconductor switch that is advantageous for speeding up and extending the life, and yet also generates electric corrosion. An object of the present invention is to obtain an electrical operation device for a circuit breaker that is prevented.

  An electric operation device for a circuit breaker according to the present invention includes a motor serving as a power source for operating a handle of the circuit breaker via a mechanism portion, and the motor connected in series to both positive and negative power supply input terminals of the motor. A normally open contact that is closed when the motor is driven, a normally closed contact that is connected in parallel to the positive and negative power input terminals of the motor and that is open when the motor is driven, and a relay that controls the normally open and normally closed contacts. The limit switch signal following the ON signal and switching of the circuit breaker from the open state to the closed state or the OFF switch and the limit switch following the switching of the circuit breaker from the closed state to the open state It has a semiconductor switching element controlled by a signal, and the electric action on the normally open contact is different between when the motor is driven and when it is stopped. Than is.

  As described above, the present invention can provide an electric operating device for a circuit breaker that is excellent in environmental resistance in addition to high speed and long life.

It is a circuit diagram of the electrical operation apparatus of the circuit breaker which shows Embodiment 1 of this invention. It is a timing chart figure which shows operation | movement of each part in FIG. FIG. 3 is a view corresponding to FIG. 1 showing Embodiment 2 of the present invention. FIG. 3 is a view corresponding to FIG. 1 showing Embodiment 3 of the present invention. It is a circuit diagram which shows the detection circuit and self-holding circuit in Embodiment 3 of this invention. FIG. 5 is a timing chart illustrating the operation of each unit in FIG. 4. It is a circuit diagram which shows another embodiment of the detection circuit and self-holding circuit in Embodiment 3 of this invention.

Embodiment 1 FIG.
FIG. 1 is a circuit diagram of an electric operating device for a circuit breaker according to Embodiment 1 of the present invention, and FIG. 2 is a timing chart showing the operation of each part. In the present invention, when the circuit breaker is turned on at high speed, a spring (of an electric operation device (not shown)) is stored during the OFF operation, and the circuit breaker is instantaneously operated by the force of the spring during the ON operation. It will be described as a so-called “off-charge type electric operation device” which is brought into a closed state.

  In FIG. 1, reference numeral 101 denotes an ON switch 41 serving as an ON signal generation source, an OFF switch 42 serving as an OFF signal generation source, a limit switch 43 that follows a cam of an electric operation device (hereinafter referred to as a device), and 1 is a circuit diagram of a device including a motor 44 as a power source for operating a handle of a circuit breaker (not shown) (not shown) via a mechanism of the device, and is supplied as a control power supply as is well known. The electrical energy is converted into kinetic energy by the motor 44, that is, the handle is moved by the mechanism part with the rotational force generated by the motor 44, and the circuit breaker to which the device is attached is closed to open or open to Closed.

  In FIG. 1, since the limit switch 43 is in the closed state on the a side, first, the operation when the OFF operation is performed from the closed state to the open state will be described in detail with reference to FIG. This OFF operation is started by pressing the OFF switch 42, and an OFF signal by this pressing is electrically held in the self-holding circuit 22 because the limit switch 43 is on the a side as described above. At this time, as shown in FIG. 2 (c), there is a time delay T1 until the self-holding circuit 22 outputs an output signal by pressing the OFF switch 42. This eliminates chattering and noise of the OFF switch 42. This is a time delay that occurs.

  An output signal from the self-holding circuit 22 is input to the gate of the semiconductor switching element 6 via the diode 2, and the semiconductor switching element 6 is turned on. As a result, the operation coil of the relay 32 is excited, the a contact 32a is closed and the b contact 32b is opened, and then the operation coil of the relay 31 is also excited by the closed a contact 32a. Since the a contacts 31a1 and 31a2 are closed (because the b contact 32b is open), power is supplied from the power source Vcc to the motor 44 via the diode 3, and the motor 44 starts to rotate. FIG. 2 (f) shows the rotation state of the motor 44. The time delay T2 due to the above-described delay of the operation of T1 and the relays 31 and 32 is relative to the OFF operation time Toff shown in FIG. Therefore, these time delays T1 and T2 do not affect this operation.

  When the motor 44 starts rotating, as shown in FIGS. 2 (g) and 2 (i), the cam, which is decelerated and interlocked by the gear of the device, starts rotating, and the spring starts storing energy. The circuit breaker handle is interlocked with the cam to be operated, and the circuit breaker shifts from the closed state to the open state. Here, as is clear from FIGS. 2C, 2F, and 2I, the self-holding circuit 22 causes the motor to move until the handle is moved to the open state and the spring accumulation is reliably completed. The rotation of the shaft 44 is maintained, but this is because even if the pressing of the OFF switch 42 is stopped halfway, the “transition to the open state” and the “off charge” can be reliably performed, Therefore, it forms “self-holding”.

  The motor 44 stops rotating when the above-described “transition to the open state” and “off charge” have been completed, as shown in FIGS. 2 (g) and 2 (h). The limit switch 43 is switched at a predetermined rotation angle θ of the cam. That is, the limit switch 43 that operates in conjunction with the cam in the transition from the closed state to the open state switches from the a side to the b side at the predetermined rotation angle θ of the cam described above, and the power supply to the self-holding circuit 22 Supply is stopped. As a result, the output signal to the semiconductor switching element 6 is lost by releasing the “self-holding”, the semiconductor switching element 6 is instantaneously turned off, and the power supply to the relays 31 and 32 and the motor 44 is also stopped. Is done.

  When the power supply to the motor 44 is stopped, the motor 44 is in an inertial rotation state, and the excitation of the operation coil is released in the order of the relay 32 and the relay 31, and the first and second a contacts 31 a 1. When both 31a2 are open, the motor 44 is in the state shown in FIG. 1, that is, completely insulated from the control power supply, and the b contact 32b is closed, and the resistance connected in series to the b contact 32b. 11, the regenerative energy of the motor 44 is consumed, whereby the motor 44 is braked in a short time. The diode 4 suppresses a surge voltage generated from the motor 44 in a short time until the b contact 32b is closed. In the diode 3, the regenerative current of the motor 44 flows backward to the operation coils of the relays 31 and 32 in a short time until the first and second a contacts 31 a 1 and 31 a 2 are opened. This prevents the return time, that is, the time for releasing the excitation from being delayed.

  Thus, in the present invention, the semiconductor switching element 6 is turned off simultaneously with the switching of the limit switch 43, so that the power supply to the motor 44 is stopped. Simultaneously with this stop, the above-described surge voltage suppression is suppressed. This is a short time until the b-contact 32b is closed by the diode 4 for this purpose, but this time is not wasted and the motor 44 starts decelerating by starting to consume the regenerative energy of the motor 44. The time delay T3 from when the limit switch 43 is switched to when the motor 44 starts the braking operation shown in FIG. 2F can be shortened. The effect of shortening the time delay T3 is utilized in the open state to the closed state, that is, the ON operation described below.

  As shown in FIG. 2 (e), the ON operation is started by pressing the ON switch 41, and the ON signal due to the pressing is coupled with the open state in which the limit switch 43 is on the b side. The one-pulse circuit 21 converts the signal to a one-pulse signal that is output only for a predetermined output time T5 after the ON switch 41 is pressed. At this time, there is a time delay T4 until the one-pulse circuit 21 outputs an output signal when the ON switch 41 is pressed. This is the time generated for removing chattering and noise of the ON switch 41 as in the OFF operation. It is a delay.

  The output signal from the one-pulse circuit 21 is input to the gate of the semiconductor switching element 6 via the diode 1 and the semiconductor switching element 6 is turned on, but the subsequent operations of both the relays 31 and 32 and the motor 44 are as follows. Same as OFF operation, omitted. As shown in FIG. 2 (f), as in the case of the OFF operation, a time delay T2 due to the operation delay of both the relays 31 and 32 occurs. Therefore, the output operation T5 described above is reliably performed by the ON operation described below. Therefore, the time considering T2 is used.

  When the motor 44 starts rotating, as shown in FIG. 2G, the cam starts rotating from an angle slightly exceeding the rotation angle θ, and the dead angle rotation angle (in this case, 360 from the start of the OFF operation). At the initial rotation angle), the device is unlatched and the stored spring is released. At the same time that the breaker handle is moved from the open state to the closed state by the force of the released spring, the limit switch 43 is switched from the b side to the a side, which is also apparent from FIGS. 2 (a) and (i). In this way, the circuit breaker is closed, and the mechanism of the device is discharged.

  By switching the limit switch 43 to the a side, power supply to the one-pulse circuit 21 is stopped, and the output signal to the semiconductor switching element 6 of this one-pulse circuit 21 is lost without waiting for the predetermined output time T5 described above. The semiconductor switching element 6 is instantaneously turned off, but the subsequent operations of both the relays 31 and 32 and the motor 44 are omitted since they are the same as the OFF operation. As shown in FIG. 2F, the motor 44 is in a so-called initial state before the start of the OFF operation when the braking is performed and the motor 44 is completely stopped.

  As described above, in the present invention, the motor 44 is completely insulated from the control power source to prevent electric corrosion, and the “high speed / long life” is achieved by turning the semiconductor switching element 6 on and off. As is apparent from the above description, this is largely due to a device that devised the electrical action of the a contacts 31a1 and 31a2 for driving and stopping the motor 44. That is, when driving, both relays 31 and 32 are operated, and then the power is supplied to the motor 44 via the closed contacts a 31a1 and 31a2, whereas when stopped, the semiconductor switching element 6 is turned on. After turning off the power supply and turning off the power supply, the a contacts 31a1 and 31a2 are opened by the cut-off power supply. In general, it is obvious that the contact is more “turned” than “turned on” when the arc is generated, so that the contact is provided at both the positive and negative power input terminals of the motor 44. However, a long life can be achieved.

  The semiconductor switching element 6 can be turned on and off by another point of “speeding up”. In the present invention, “further speeding up” is realized by the above-mentioned “shortening of the time delay T3”. In other words, by shortening the time delay T3, the difference between the rotation angle at which the cam latch is released and the rotation angle θ at which the limit switch 43 is switched is reduced, and this switching point becomes a dead point for opening the spring. Since it was made closer, the rotation angle of the cam during the ON operation can be reduced, and the ON operation time Ton shown in FIG. 2A was shortened. This is because when the limit switch 43 is switched at a predetermined rotation angle θ of the cam, the semiconductor switching element 6 is turned off and the power supply to the motor 44 is stopped. This is because the braking operation is started by the diode 4. Therefore, by stopping the power supply to the motor 44 by the semiconductor switching element 6, the return time of both relays 31 and 32 having large variations does not affect Ton, and a contact is made between the positive and negative power input terminals of the motor 44. It has become possible to provide both "high speed and long life" and "preventing electric corrosion" at the same time.

  As a result, regardless of the leakage current of the semiconductor switching element 6, the winding and the control power source are insulated when the motor 44 is stopped, so that the insulation from the ground can be reliably performed. As a result, even in a small motor that is relatively difficult to secure insulation against a mechanism frame that is often grounded for safety, there is no potential difference between the winding and the outer shell. Thus, it is possible to prevent the electric corrosion phenomenon of the winding caused by the potential difference. Further, since the motor 44, the relays 31 and 32, the diodes 3 and 4, and the resistor 11 are regarded as “one load unit” and controlled by the semiconductor switching element 6, the volume is reduced as shown in FIG. Except for the first substrate unit 51 configured by wiring to the motor 44 having a large current capacity and the relays 31 and 32, and the semiconductor switching element 6, it can be configured by only a small signal electronic component and a printed wiring board. Since the second substrate unit 52 can be separated, not only the wiring is simplified, but also the assembly of the printed wiring board is facilitated.

  The prohibition signal from the self-holding circuit 22 to the one-pulse circuit 21 shown in FIG. 1 cancels the ON operation in preference to the OFF operation when the user accidentally presses the OFF switch 42 and the ON switch 41 simultaneously. In this way, a malfunction phenomenon called so-called pumping operation that repeats the ON operation and the OFF operation is prevented, and the one-pulse signal is not output by the prohibition signal output from the self-holding circuit 22. In the present invention, two relays, that is, the relay 31 and the relay 32 are used. When the semiconductor switching element 6 is turned on, the a contacts 31a1 and 31a2 are closed before the b contact 32b is opened. This is because the b contact 32b is surely opened first by operating the relay 31 after the operation of the relay 32 so that an excessive current does not flow. If the contacts 31a1 and 31a2 can be opened earlier than the contacts 31a1 and 31a2, the relays may be configured by one relay. Furthermore, although the resistor 11 is provided for braking the motor 44, it goes without saying that the resistor 11 can be omitted if there is no effect on the contact of the motor 44 and the relays 31 and 32.

Embodiment 2. FIG.
In the first embodiment, it has been described that the time required to drive the motor 44 is the same regardless of whether it is an ON operation or an OFF operation. However, for example, due to welding of the contact of the circuit breaker or abnormality of the mechanism part of the device, the handle When the operation load of is extremely large, the above-described time may be increased. In the second embodiment, a function of detecting the increased time, that is, the abnormality of the apparatus and stopping the operation to notify the user of the abnormality and to prevent the apparatus from being burned by overload is added. FIG. 3 is a view corresponding to FIG. 1 in the second embodiment.

  While the motor 44 is being driven, an output signal is output from either the self-holding circuit 22 or the one-pulse circuit 21 to the semiconductor switching element 6. ON voltage (in the case of MOSFET, generally 2V to 4V) is generated. Since the driving of the motor 44 and the presence or absence of the input voltage of the semiconductor switching element 6 are always linked, the time during which the input voltage is generated continuously exceeds the normal OFF operation time or ON operation time. In this case, it can be determined that an abnormality has occurred in the circuit breaker or the device.

Therefore, when the input terminal of the semiconductor switching element 6 is input to the integration circuit 23 via the diode 5 and the voltage of the integration circuit 23 reaches a predetermined voltage, the semiconductor switching element 6 is more than expected. Is turned on, and the thyristor 7 is turned on. Then, the voltage at the input terminal of the semiconductor switching element 6 is suppressed, the semiconductor switching element 6 is turned off, and the motor 44 quickly stops driving. Further, an LED 8 is connected to the anode of the thyristor 7 via a resistor 13, and the user can know an abnormal state by turning on the LED 8. This lighting is continued by supplying a holding current to the thyristor 7 until the control power supply is noticed abnormally and turned off. The “first self-holding circuit” described in the claims is the thyristor 7.

  Here, the diode 5 is for backflow prevention that prevents the current from the resistor 13 and the LED 8 from flowing into the semiconductor switching element 6 and causing the semiconductor switching element 6 to malfunction. Further, the resistor 12 restricts an excessive current from flowing from each output of the self-holding circuit 22 or the one-pulse circuit 21 to the thyristor 7 when the thyristor 7 is ON. In the second embodiment, the ON time of the semiconductor switching element 6 is determined by the integrating circuit 23. However, instead of the integrating circuit 23, the output signal is output when the input time exceeds a predetermined time. The same effect can be expected even when a timer circuit is used.

Embodiment 3 FIG.
4 is a circuit diagram of an electrical operation device for a circuit breaker according to Embodiment 3 of the present invention, FIG. 5 is a circuit diagram showing a detection circuit and a self-holding circuit, FIG. 6 is a timing chart showing the operation of each part, and FIG. These are circuit diagrams which show another embodiment in a detection circuit and a self-holding circuit. In the second embodiment, it is detected that the time required to drive the motor 44 becomes longer than a predetermined time when the handle operating load becomes extremely large due to welding of the contact of the circuit breaker or the like. In the third embodiment, the operation is stopped by detecting that the driving current of the motor 44 increases when the operation load of the handle becomes extremely large, and this abnormality is notified to the user and overloading is performed. This prevents the electrical operating device from burning out.

  In FIG. 4, the difference in configuration from the first and second embodiments will be described. In the first and second embodiments, the operation coils of the first and second relays and the motor 44 are both driven by the semiconductor switching element 6. However, in the present embodiment, the motor 44 is driven by the semiconductor switching element 6. However, the operation coils of the first and second relays are second semiconductors whose bases are connected to the gates of the semiconductor switching elements 6 via resistors 62 so as to operate in synchronization with the semiconductor switching elements 6. It is driven by the switching element 61.

  Further, a resistor 63 which is a current detection resistor is inserted between a path through which the drive current of the motor 44 flows, that is, between the semiconductor switching element 6 and the ground, and the drive current of the motor 44 generated at both ends of the resistor 63. Is detected by the detection circuit 64. A second self-holding circuit 65 is connected to the output of the detection circuit 64, and when the drive current of the motor 44 exceeds a predetermined value (for example, 120% of the rated current of the motor), the output of the detection circuit 64 The second self-holding circuit 65 becomes conductive, the input voltage of the semiconductor switching element 6 connected to the second self-holding circuit 65 via the diode 67 is suppressed, and the semiconductor switching element 6 is turned off.

  A resistor 69 and an LED 68, the other of which is connected to the power supply Vcc, are connected in series to the connection point of the second self-holding circuit 65 and the diode 67. When the second self-holding circuit 65 becomes conductive, at the same time, a current also flows through the LED 68, and the LED 68 lights up to notify the user of the abnormality, and the current flowing through the LED 68 becomes the holding current of the thyristor 65a. Thus, the OFF state of the semiconductor switching element 6 is maintained.

  As shown in FIG. 5, the detection circuit 64 includes resistors 64a1 and 64a2 connected so as to divide the voltage generated at both ends of the resistor 63. The connection point between the resistor 64a1 and the counter 64a2 is connected to the gate of the thyristor 65a constituting the second self-holding circuit 65, and the voltage at the connection point between the resistor 64a1 and the counter 64a2 becomes the ON voltage specific to the element of the thyristor 65a. When reaching, the thyristor 65a becomes conductive. When the drive current of the motor 44 exceeds a predetermined value determined by the voltage dividing ratio of the resistor 63 and the resistors 64a1 and 64a2, the thyristor 65a becomes conductive, and the input voltage of the semiconductor switching element 6 is suppressed via the diode 67. Then, the semiconductor switching element 6 is turned off.

  As described above, by appropriately setting the resistor 63 and the resistors 64a1 and 64a2, when the driving current of the motor 44 increases abnormally, the semiconductor switching element 6 is turned off to prevent the apparatus from being burned by overload. However, if it is left as it is, there is a problem that the starting current of the motor 44 is detected as an abnormal current despite the normal state.

  Therefore, in the present embodiment, the timer starts to operate with the same input signal as that of the semiconductor switching element 6, and after the semiconductor switching element 6 is turned on, a predetermined time during which the drive current of the motor 44 becomes a steady current from the starting current. And a third semiconductor switching element 70 that opens the short circuit across the resistor 63 by the operation of the second timer circuit 71. The third semiconductor switching element 70 is normally in a conducting state, but is brought into a non-conducting state due to the delayed Lo output of the second timer circuit 71, so that both ends of the resistor 63 are connected for a predetermined time from the start of the motor 44. As a short circuit state, the function of the detection circuit 64 is stopped.

Next, the operation of each part in a state where the contact of the circuit breaker is welded and the handle of the circuit breaker cannot be normally returned to the disconnecting position will be described with reference to FIG.
In FIG. 6 (a), X represents a point where the contact is opened by a normal circuit breaker and switched from ON to OFF, and Y represents a large operation load on the circuit breaker handle when the circuit breaker contact is welded. The point that becomes.

  FIG. 6E shows the load current of the motor 44. During the operation time T6 of the timer circuit 71 from the start of the motor 44, the third semiconductor switching element 70 is in a conductive state, and the resistor 63 Since both ends of the thyristor 65 are short-circuited, the thyristor 65a does not operate. Therefore, the starting current of the motor 44 is not detected.

  On the other hand, after the operation time T6 of the second timer circuit 71 has elapsed since the start of the motor 44, the third semiconductor switching element 70 is turned off and the short circuit across the resistor 63 is opened. An abnormal current is detected by the detection circuit 64 by a voltage proportional to the load current of the motor 44 generated in the above. As described above, the magnitude of the current detected by the detection circuit 64 is the ON voltage specific to the element of the thyristor 65a and the predetermined threshold value It determined by the resistor 63 and the resistors 64a1 and 64a2. When the load current of the motor 44 reaches the area A shown in FIG. 6, the thyristor 65a becomes conductive as shown in FIG.

  Due to the conduction of the thyristor 65a, the semiconductor switching element 6 and the third semiconductor switching element 70 become non-conductive, and the input of the second timer circuit 71 is also turned off. As shown in FIG. The output of the circuit 71 becomes Hi.

  In addition, the resistor 63 functions as a current detecting resistor that converts current into voltage as well as a current limiting resistor that suppresses the drive current of the motor 44, and has a constant speed from the start of the motor 44 that requires the most torque. Since the third semiconductor switching element 70 connected in parallel to the resistor 63 is in a conductive state during the rotation, the motor 44 is driven with little power loss, and after the operating time T6 has elapsed, the third semiconductor switching element 70 is operated. The element 70 becomes non-conductive and the resistor 63 functions to limit the drive current of the motor 44.

  Since the torque of the motor 44 is reduced by this current limiting action, when the contact of the circuit breaker is in a welded state, the motor speed is also reduced in a chain, so that the current change of the motor 44 is increased. It becomes easy to detect as an abnormal current, and at the same time, it is possible to reduce an excessive load and an impact on an operation unit such as a handle of a circuit breaker.

  In the second embodiment, the semiconductor switching element 6 collectively drives the motor 44 and the operation coils of the relays 31 and 32. However, in the third embodiment, the semiconductor switching element 6 is operated by the same input signal as that of the semiconductor switching element 6. The second semiconductor switching element 61 is provided to drive the operation coils of the relays 31 and 32 separately from the motor 44. In the second embodiment, the reverse current blocking diode 3 is necessary so that the regenerative current of the motor 44 does not flow backward to the operation coils of the relays 31 and 32. However, when the drive current of the motor 44 is large, the diode 3 is also A large capacity is required, and when a low voltage motor is used as the motor 44, a voltage drop due to the diode 3 cannot be ignored. Therefore, in the third embodiment, the second semiconductor switching element 61 that performs the same operation as the semiconductor switching element 6 is provided to drive the operation coils of the relays 31 and 32, thereby eliminating the backflow prevention diode 3. .

  Since the drive current of the operation coils of the relays 31 and 32 is very small compared to the drive current of the motor 44, the second semiconductor switching element 61 can use a general-purpose transistor for small signals. In the case where a diode 3 having a large capacity is required, the third embodiment is advantageous in terms of mounting space and cost.

  In the third embodiment, the second timer circuit 71 sets the ON time of the third semiconductor switching element 70. However, instead of the second timer circuit 71, the input time is a predetermined time. A similar effect can be expected by using an integration circuit that sets the output signal to Lo when the time is exceeded.

  As shown in FIG. 7, the detection circuit 64 includes a Zener diode 64b2 connected to both ends of the resistor 63 via the resistor 64b1, a transistor 64b3 whose base is connected to the anode of the Zener diode 64b2, and a collector of the transistor 64b3. The base of the transistor 64b4 may be connected to the transistor 64b5. The collector of the transistor 64b5 is connected to the gate of the second self-holding circuit 65 via the resistor 64b6. When the voltage across the resistor 63 exceeds the Zener voltage of the Zener diode 64b2, the transistors 64b3 and 64b5 are connected. Turned on and the second self-holding circuit 65 becomes conductive. As the detection circuit 64, a current detection circuit may be configured by a comparison circuit using a comparator or a Schmitt trigger circuit, and the same effect can be expected.

  The second semiconductor switching element 61 drives the operation coils of the relays 31 and 32, and the semiconductor switching element 6 drives the motor 44. However, the second semiconductor switching element 61 drives the motor 44 and the semiconductor switching element 6 May drive the operation coils of the relays 31 and 32. In this case, a general-purpose transistor for small signals cannot be used for the second semiconductor switching element 61, but a general-purpose transistor for small signals can be used for the first semiconductor switching element 6.

3 diode, 6 semiconductor switching element, 7 thyristor, 11 resistance,
21 One-pulse circuit, 22 Self-holding circuit, 23 Integration circuit,
31 1st relay, 31a1 1st a contact, 31a2 2nd a contact,
32 second relay, 32b b contact,
41 ON switch, 42 OFF switch, 43 limit switch,
44 motor,
101 Electric operating device.

Claims (6)

A motor that serves as a power source for operating the handle of the circuit breaker via the mechanism, a normally open contact that is connected in series to both positive and negative power input terminals of the motor and is closed when the motor is driven, and the motor A normally closed contact connected in parallel to both the positive and negative power supply input terminals and opened when the motor is driven, a relay for controlling the normally open and normally closed contacts, an ON signal and the circuit breaker from the open state are closed. A first switch element controlled by a limit switch signal following the switching to the state, or an OFF signal and the limit switch signal following the switching of the circuit breaker from the closed state to the open state; In a circuit breaker electrical operation device that operates the circuit breaker by inputting the ON signal or the OFF signal,
An electric operation device for a circuit breaker, wherein the electric action for the normally open contact is different between when the motor is driven and when the motor is stopped.   The motor is driven by closing the normally open contact after the first semiconductor switching element is turned on, and the motor is stopped by turning off the first semiconductor switching element. The electrical operating device for a circuit breaker according to claim 1.   A diode provided between the motor and the operation coil of the relay, for preventing regenerative energy generated in the motor from flowing into the operation coil; a first semiconductor switching element comprising: the motor and the operation coil; 3. The circuit breaker electrical operation device according to claim 1, wherein a drive current is supplied to both.   A second semiconductor switching element that operates in synchronism with the first semiconductor switching element, wherein the second semiconductor switching element is one of the operating coils of the motor or relay, and the first semiconductor switching element is a motor or relay; The electric operating device for a circuit breaker according to claim 1 or 2, wherein a driving current is supplied to the other operating coil.   A first integration circuit or timer circuit that operates in conjunction with the voltage at the input terminal of the first semiconductor switching element, and a first self-holding circuit that maintains conduction by the output of the first integration circuit or timer circuit; 5. The circuit breaker electrical operating device according to claim 1, wherein the voltage is suppressed by the first self-holding circuit being conductive. 6. .   A current detection resistor provided in a path through which the motor drive current flows, a detection circuit for detecting the motor drive current based on a voltage across the current detection resistor, and an input signal input to the first semiconductor switching element The second integration circuit or timer circuit that operates after a predetermined time has elapsed after the first semiconductor switching element is turned on in conjunction with the voltage at the end, and the operation of the second integration circuit or timer circuit A third semiconductor switching element that opens a short circuit across both ends of the current detection resistor, and a second self that holds the first semiconductor switching element non-conductive when the detection current of the detection circuit exceeds a predetermined value. The circuit breaker electrical operation device according to claim 1, further comprising a holding circuit.

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