KR900007581B1 - Power circuit - Google Patents

Abstract

The input terminal (1) is connected to power source. A rectifier (2) provides the operating power to a controller (6) and a relay (9). The current flowing to the load is set by a current setting circuit (4). The overcurrent which is larger than the setting value is detected by a current sensor (3) and amplified by an amplifier (5). The amplified signal is provided to a fault signal generator (6) which excites the coil of the relay to cut off the overcurrent and turns on a lamp (7) to indicate the fault state so that the load like main electronic circuit is protected from the overcurrent. The protector which has been operated is reset by a reset switch (8).

Description

Electronic circuit protection device using I.C

1 is a device display of the present invention.

2 is a configuration diagram of part A of FIG. 1;

3 (a) is a configuration diagram of a conventional fuse product.

(b) is a configuration diagram of a conventional mechanical protector.

* Explanation of symbols for main parts of the drawings

A, A ', A': Protective device part 1: Input terminal part

1 ', 1 ": Input terminal 2: Power supply and rectifier

3: conduction current sensing unit 4: load current setting unit

5 amplification unit 6 fault signal generating unit

6 ': control unit 7: fault indication lamp

8: northern part 2: relay part

10: Output terminal part 10 ', 10 ": Output terminal

11: load part

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic circuit protection device used to protect an electronic circuit (hereinafter, referred to as an electronic circuit) using I.C from an abnormal current.

Conventional electronic circuit protection devices mainly use semiconductor protection fuses and mechanical protectors (manufactured by Matsushita, Japan), but semiconductor protection fuses are not suitable for protecting semiconductors such as ICs because of their long operating time in case of abnormal current. The mechanical protector has a large voltage drop due to the inductance component of the coil when the energized current is small, and the power factor of the current drops significantly, resulting in poor operation and power loss. There was a disadvantage.

The present invention is characterized in that the electronic circuit protection device that complements it electronically in solving the above pattern will be described in detail according to the configuration thereof according to the drawings.

On the left side of the protection device A, an input terminal part 1 is configured, and on the right side, an output terminal part 10 and a load part 11 are configured. 3), the amplifier 5, the fault signal generating unit 6, the relay unit 9 in the order of the current carrying current detection unit 3, one side of the load current setting unit 4 is connected, the amplifier ( 5) one side is directly connected to the power supply and rectifier (2), the fault signal lamp (7) is connected to one side of the fixed signal generator (6) and the return part (8) and the power supply and rectifier (2) is Is connected, one side of the relay unit 9 is a structure directly connected to the power supply and rectifier (2). Reference numeral 12 is a fuse and 13 is an inductance.

When the present device is implemented as described above, the terminals 1 'and 1 "of the input terminal unit 1 are connected to a power source, and the load (the terminals 10' and 10" of the output terminal unit 10 is connected to a load ( Electronic circuit), the power supply unit and rectifier unit 2 supplies the operating power to the control unit 6 'and the relay unit 9, and the load current setting unit 4 supplies electricity to the load circuit. The current is set, and the conduction current sensing unit 3 detects when a current equal to or greater than the set value set by the load current setting unit 4 is energized, and the amplifying unit 5 performs the conduction current sensing unit ( Amplifies the abnormal current detected in 3) to send a signal to the fault signal generator (6).

In response to the failure signal, the failure signal generator 6 excites the coil of the relay unit 9 to open the terminal of the relay unit 9 to serve as a blocker for the load circuit.

In addition, the return 8 allows the load current to be energized again by pushing only when the cause of failure is eliminated.

The fault signal lamp 7 indicates the interruption of the load current in the case of a fault and in this case the lamp 7 is turned on. (OFF when energizing load current)

The relay unit 9 directly energizes the load current and, in the event of an abnormality, receives a signal from the fault signal generator 6 and cuts off the load current.

Comparing the present apparatus as described above with the conventional apparatus is as follows.

First, in the conventional device, the fuse protection device for semiconductor

(A) Due to the long operating time due to abnormal current, various devices connected to the load may be damaged during this operating time, so sufficient protection may not be obtained.

(B) The fuse 12 cannot be used after one use and must be replaced with a new one.

(C) There is no function to indicate when the circuit is cut off.

And conventional mechanical protector protection device

(A) It is a mechanical type, so its operation time is very slow.

(B) When the load current is small, the voltage drop due to the inductance component of the coil is so large that the specified voltage cannot be applied to the load, resulting in poor operation of the equipment.

(C) The above inductance component adversely affects the loss and load caused by ground current.

However, according to the device of the present invention

first. When abnormal current is input, the operation time is very fast, so it is possible to completely protect semiconductor circuits such as I.C. That is, it detects within 1/120 seconds and generates a blocking signal.

second. Since there is no voltage drop on the output shaft, no malfunction occurs in various devices connected to the load 11.

Third. There is no inconvenience in having to replace the fuse again as in the prior art in case of failure.

fourth. The load current is set so that it can be used to control various load currents as a circuit protection device.

fifth. In case of failure, it is very easy to diagnose the fault because it displays through lamp.

Sixth. Since the pushbutton is not put in the state that the fault is not completely eliminated, it is possible to prevent the failure propagation closing as much as possible.

Seventh. The effect of import substitution is large and can greatly contribute to industrial development.

Claims (1)

On the left side of the protection device A, an input terminal part 1 is configured, and on the right side, an output terminal part 10 and a load part 11 are configured. 3), the amplifier 5, the fault signal generator 6, the relay unit (9) in order, the current carrying current sensing unit (3) side of the load current setting unit (4), the amplifier One side of (5) is directly connected to the power supply and rectifier (2), one side of the fault signal generating unit (6) is connected to the fault indicator lamp (7), the other side is connected to the return unit (8) and the power Electronic circuit protection device using an IC and the like connected directly to the rectifier (2) and connected to the power supply and rectifier (2) on one side of the relay unit (9).

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