JPS61124220A - Current breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to current circuit breakers such as safety circuit breakers and earth leakage circuit breakers.
AL, aims to provide a highly reliable current circuit breaker.

[Conventional technology]

As shown in FIG. 4, the conventional flow breaker is constructed so that the current from the terminal okara passes through a movable spring 32 and flows through a fixed contact 37 to the terminal fitting.

Further, since the material of the movable spring 32 is bimetal, when an excessive current flows, the movable spring 32 bends upward against the arcuate spring 36, and the movable contacts are opened and no current flows to the terminal 34. When returning to the original state, press the knob 31 and touch the movable resistance 38f/interim contact π to return to the original state P?
Set ζ.

[Problem that the invention seeks to solve]

As mentioned above, conventionally, the contacts are opened and closed by the movable spring 32 made of bimetal, which increases the wear and tear of the contacts. Furthermore, since it is easily affected by ambient temperature, its operation becomes unstable, and since there are many movable parts, its operation is inconsistent and lacks reliability.

Therefore, a technical problem in the current breaker of the present invention is to configure it with an electronic circuit instead of using a current breaker with a conventional configuration.

[Means for solving problems]

In order to solve the above technical problem, the current breaker of the present invention surrounds one line of the power supply line 22 with a ring core 10, and the voltage generated in the coil wound around the ring core 10 and the preset voltage are set. a comparator 3 that compares the values, a monostable multivibrator 4 that outputs a pulse signal in response to the pulse a from the comparator 3, a transistor 13 for switching, and a magnetic relay 2 that turns off the snow field switch 1.
1.

[Effect]

This technical measure works as follows.

One line of the power supply line 22 is surrounded by a ring core 10, and a comparator 3 is used to compare the voltage generated in the ring core 10 with a preset voltage.

It is detected whether the current is flowing normally in the source line 22, and when the current flows excessively and the voltage generated in the ring core 10 is higher than the set voltage, a pulse b is generated from the monostable multivibrator 4, and the monostable multivibrator 4 generates a pulse b. If an excessive current continues to flow through the power supply line 22 even after the set time of the multivibrator 4 has elapsed, A
The output d of the ND circuit 6 becomes Q1, the output of the ant 11 is held in the latch circuit 8, and the transistor 13 is turned on.
When the current from the power source 1B flows into the electromagnetic coil 12, the electromagnetic relay 4 operates to turn off the power switch 1.

〔Example〕

Fig. 1 is a circuit diagram showing a current tracing breaker according to the present invention, Fig. 2 is a timing chart of output pulses in the state where an excessive current flows according to the present invention, and Fig. 3 is an output pulse according to the present invention in the event of an earth leakage. The timing chart of each is shown below. In the figure,
1 is a power switch, 2.16 is a filter, 3.17 is a comparator, 4,5°18, 19 is a monostable multivibrator, 6.2+1 is an AND circuit, 7 is an OR circuit, 8 is a latch circuit, 9 is a Light emitting diodes, 10 and 15 are ring cores, 12 are electromagnetic coils, 13 and 14 are transistors, 2
1 represents an electromagnetic relay.

The operation will be specifically explained based on FIGS. 1 to 3. First, when t and i flow through the power line 22, a voltage is generated in the ring core 10 surrounding one side of the power line 22. A voltage corresponding to a specified current flowing through the power supply line 4 is set in advance by dividing the voltage of the power supply 1B connected to one terminal of the comparator 3. ring core 1
The voltage generated in the coil wound at zero is input to the left terminal of the comparator 3 via the noise prevention filter 2.
The comparator 3 compares the input voltage from the filter 2 and the voltage set by dividing the W source 10B, and if the output voltage from the filter 2 is higher than the set voltage, the valve will detect an excessive current in the power line 22. is flowing.

At this time, as shown in FIG.
is generated and input to the monostable multivibrator 4.

Here, an excessive current may momentarily flow due to a rush current when the power is turned on in the power supply line 22, and a pulse a may be generated from the comparator 3. Taking this into consideration, the period of the pulse b (T) is set.

-)-8,)' are set. As a result, when an excessive current momentarily flows through the power supply line 22, the pulse a is no longer generated after a time of 1'1, so the output pulse b of the monostable multivibrator 4 remains at a high level for the first time of 1'1. Even if the monostable multivibrator 5 generates a high-level output C, the AND circuit 6 does not generate the IS 1 p output, so the electromagnetic relay 21 operates and current continues to flow through the power supply line 4. When an excessive current continues to flow through the source line 22, the pulse a from the liquid comparator 3
The output pulse b of the monostable multivibrator 4 is generated continuously based on Only when b and c are both at high level, the output of the AND circuit 6 becomes whisper 1 and pulse d is generated. Next, the 11N pulse input to the OFt circuit 7 is temporarily held in the latch circuit 8, and when the switching transistor 13 is turned on and current flows from the power source 1B toward the emitter, the electromagnetic relay 21 is operated by the electromagnetic coil 12. let As a result, the power switch 1 is turned off, so that the excessive current flowing through the power line 22 can be cut off. Note that this time T can be arbitrarily set to account for rush current and discontinuous noise when the power is turned on, and it is preferable to set the minimum increase to the synchronization of the power supply.

In addition, in the event of a current leakage, the ring core 15 surrounding the two 11 source lines n generates a voltage due to the difference in the current in each line, and a noise prevention filter 16 is generated from the coil wound around the ring core 15. Comparator 17 via
be input to one terminal of the . The comparator 17 compares the voltage generated in the ring core 15 due to the difference in current between each line of the power supply line 22 with the voltage generated when the current flowing through the power supply line 22 from the power source 10B is normal.
If the input voltage from the power supply line 22 is higher than the input voltage from the power supply line 22, it means that there is a current leakage in the power supply line 22. Then, a pulse e having the same period as the power line 22 is generated from the comparator 17 and inputted to the monostable multivibrator 18. Then, since the output pulse hBt of the nuclear monostable multivibrator 18 and the output pulse k of the monostable multivibrator 19 are both 11〃, the output pulse m of the AND circuit 20 becomes whisper 1 and is input to the OR circuit 7. The signal of -H latch circuit 8
is held in The switching transistor 13 is turned on by this signal, and the signal is turned on from the power source 1B to the emitter.
When current flows, the electromagnetic relay 4 is operated based on the electromagnetic coil 12, and the power switch 1 is turned OFF, so that the leakage of the power line 22 can be interrupted. Said time T.

The time can be arbitrarily set to protect against rush current and unlucky noise when the power is turned on, and the minimum T can be set to the power supply frequency.

In addition, since a power input signal f is provided, the power input signal f
When a signal from -11 is inputted to the OR circuit 7, the magnetic relay 4 is activated, and the source switch 1 can be turned off. Further, the latch reset signal g can be used to reset the signal of the latch circuit 8 and set it to the original state. Since the light emitting diode 9 is provided, when the latch circuit 8 holds the pulse 11, the switching transistor 14 is turned on, and the current from the power supply 1B can be used to indicate an abnormality. It is.

〔effect〕

Since the current trace disconnector of the present invention is constructed of an electronic circuit, it can instantaneously cut off the power at high speed, has little contact wear, and is less susceptible to other external influences such as temperature and humidity. Also, the multi-vibrator makes it easy to set the time.

Furthermore, since it is also equipped with a circuit for a current loop circuit breaker, it can serve as both a current circuit breaker and an earth leakage I circuit breaker.

[Brief Description of the Drawings] Fig. 1 is a circuit diagram showing a V current circuit breaker according to the present invention. Figs. 2 and 3 are timing charts showing output pulses of each part in Fig. 1, and Fig. 4 is a current p of the conventional example. The configuration diagram of each disconnector is shown. 1... Power switch 2... Filter 3... Comparator 4.5... Monostable multivibrator 6... AND
Circuit 7...OR, circuit 8...latch circuit 10, 15...ring core 12...electromagnetic coil 21...electromagnetic relay 22,

Claims (1)

[Claims] A core that surrounds at least one of the plurality of power supply lines, and a comparator that compares a voltage generated in a coil wound around the core with a preset voltage, and based on the output of the comparator. A current breaker characterized by cutting off the power supply.