JPH0226329B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Technical Field] The present invention relates to a drive circuit for a remote control type circuit breaker.

[Background technology]

A conventional example is shown in FIG. That is, 51
5 is an electromagnetic coil that controls the circuit and disconnection body A to turn on and off; 52a and 52b are diodes;
3. A changeover switch that is linked to the on/off operation of the cutter body A; 54 and 55 are remote control switches;
56 is an AC power supply. In operation, when remote control switch 54 is turned on, diode 52a
An alternating current half wave flows in one direction through the electromagnetic coil 51, and the excitation of the coil 51 causes the plunger to move in one direction, turning on the circuit or the disconnector body A, for example. In conjunction with the ON operation of the circuit breaker body A, the changeover switch 53 is switched to the position indicated by the broken line. When the remote control switch 54 is released, it returns to normal and the current to the coil 51 is cut off. Next, when the remote control switch 55 is turned on, while the switch 55 is pressed, an AC half-wave flows through the diode 52b to the coil 51 in the opposite direction, the plunger operates in the opposite direction, and the circuit is disconnected. Main unit A is turned off. In conjunction with this off operation, the changeover switch 53 is switched to the position shown by the solid line. The drive circuit for this remote control type circuit breaker performs remote control through such operations.

However, since the current flowing through the coil 51 is an AC half-wave, if the operating voltage is lowered, the current may become zero before the operation of the electromagnet's plunger is completed. In the case of 60 cycles of AC half-wave, the non-excitation state continues for about 6 to 8 ms, so the electromagnetic plunger only operates halfway, and the plunger may be pulled back to some extent by the attraction force in the opposite direction. The problem is that the operation takes a long time because the operation is completed after about 3 to 4 AC half waves. This phenomenon can be expressed graphically as shown in Figure 2. That is, FIG. 2a is a waveform diagram of the coil due to an AC half wave, FIG. 2b is a displacement of the plunger, and _FIG .
Q ₂ is the non-excitation attraction characteristic.

[Purpose of the invention]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a drive circuit for a remote control type circuit breaker that can be operated at low voltage and shorten the operating time due to AC half-wave.

[Disclosure of the invention]

In this invention, a capacitor is connected in parallel to the coil of an electromagnet, and an alternating current half wave is supplied from a remote control unit. In AC half-wave energization in either direction, the coil is excited and the capacitor is charged in one half cycle, and the charge in the capacitor is discharged to the coil in the remaining half cycle to excite the coil. Therefore, since the plunger continues to operate without being pulled back, the operation of the plunger becomes faster.

An embodiment of this invention is shown in FIGS. 3 to 6. Figure 3 shows the circuit breaker main body A', where 1 is the stand, 2 is the cover, 3 is the bistable polar electromagnet, and 4 is the circuit breaker body A'.
is a mechanism part, 5 is a movable contact, 6 is a trip mechanism,
7 is a short circuit detection device, 8 is an overcurrent detection bimetal,
9 is a terminal device on the power supply side, 10 is a terminal device on the load side, and current is passed through the terminal device 9, flexible lead wire 11, fixed contact 12, fixed contact 13, movable contact 14, movable contact 5, flexible lead wire 15, frame 1
6, the bimetal 8, the flexible lead wire 17, the coil 18 of the short circuit detection device 7, and the terminal device 10.
The ON operation is performed by tilting the handle 19 to the right (the state shown in FIG. 3) manually or using the electromagnet 3 (the plunger 3a moves downward) while the trip mechanism 6 is in the latched state. Push the upper end of the movable contact 5 to the shaft 21
The movable contact 14 contacts the fixed contact 13 by rotating around the fulcrum. The off state is the opposite behavior (electromagnet 3
In this case, the current direction is reversed). In either of these on/off cases, the permanent magnet 3a of the electromagnet 3
It is held by the holding force. In addition, if an overcurrent flows in the on state, the bimetal 8 bends, and if a short circuit current flows, the plunger 22 of the short circuit detection device 7 operates, and in either case, the trip link 23 of the trip mechanism 6 is activated. pushed and moved, axis 2
Rotate clockwise around 4. The operation of the trip link 23 unlatches the latch link 25, and the shaft 21 rotates about the shaft 26, thereby opening the movable contact 5 while the handle 19 is held by the electromagnet 3. To reset after recovery from an accident, turn off the handle 19 (manually or with the electromagnet 3) and pull the movable contact 5 through the link 20, so the latch link 25 rotates counterclockwise to return to the reset state. It is latched to the trip link 23 of. In addition, 27 is a remote control terminal connected to the remote control switch 29;
8 is an alarm or auxiliary terminal, 29 is a trip test button, 30 is a trip display device, 31 is an arc extinguishing device, and 32 is a device for driving the trip link 23 and simultaneously forcibly opening the movable contact 5 by the operation of the short circuit detection device 7. An opening rod, 33 is a contact spring, 34 is a buffer spring, 35 is a handle 1 as shown in FIG.
A changeover switch (FIG. 4) operated by a protrusion 19a in conjunction with the ON and OFF operations of 9, 36 and 37 are diodes.

Now, the drive circuit B that remotely controls the electromagnet 3 is
The only difference from FIG. 1 is that a capacitor 39 is provided in parallel with the coil 38 of the electromagnet 3 as shown in FIG. 5, and the other configurations are the same. In this case, coil 3
When a half-wave current flows through 8, the coil 38 is excited by the half-wave, and the capacitor 39 is charged. Therefore, in the remaining half cycles, the charge in the capacitor 39 is discharged to the coil 38, and the excitation is maintained, and the plunger 3b is moved by the magnetic force in these one cycle. Therefore, the current flowing through the coil 38 becomes as shown in Fig. 6a in one AC cycle, and the displacement and attractive force characteristics Q' ₁ of the plunger are as shown in Fig. 6b and c.
It shows stable changes like . By keeping the electromagnet 3 in an excited state until the operation of the electromagnet 3 is completed in this manner, the minimum operating voltage can be lowered and the operating time of the plunger 3b can be shortened.

In the present invention, the control method for feeding power to the coil 38 is not limited to the above-mentioned embodiment as long as it is an AC half-wave method.

〔Effect of the invention〕

As described above, the drive circuit for a remote control type circuit breaker of the present invention has the advantage of being able to lower the operating voltage and shorten the operating time.

[Brief explanation of drawings]

Figure 1 is a drive circuit diagram of a conventional example, Figure 2 is an explanatory diagram showing current waveforms, plunger displacement, and attraction force characteristics.
FIG. 3 is a sectional view of a circuit breaker body according to an embodiment of the present invention, and FIG. 4 is a schematic side view of a changeover switch.
FIG. 5 is a drive circuit diagram, and FIG. 6 is an explanatory diagram showing coil current waveforms, plunger displacement, and attraction force characteristics. A'...Circuit cutter body, B...Drive circuit (remote control section), 3...Electromagnet, 38...Coil,
39... Capacitor.

Claims (1)

[Claims] 1. An electromagnet that controls the breaker body to be turned on or off depending on the direction of energization, a remote control unit that supplies an AC half-wave in a predetermined direction to the coil of this electromagnet, and a remote control unit that is connected in parallel to the coil of the electromagnet to A drive circuit for a remote control type circuit breaker, comprising a capacitor that is charged by a half wave and excites the coil by discharging into the coil during the remaining half cycle period.