KR101081007B1 - Current-limit structure of current-limit type contactor - Google Patents

Abstract

The current-limiting structure of the current-limiting conductive part of the present invention includes a fixed fixed terminal having a fixed contact point, and an elastic member such that the movable contact point is rotatably coupled to the contact base to have an elastic force in one direction, and the contact base trips. In a circuit breaker in which a movable terminal hinged to be driven by a device has a "U" shaped structure, in case of an accident current, the electromagnetic repulsive force (F _L ) of the "U" shaped structure, and a fixed contact point and a movable contact point The repulsive force combined with the contact repulsion force (Fs) by the repulsive force of the working shaft to trip and extinguish the attraction force combined with the repulsive force (Fc) according to the electromagnetic repulsion force (F _L ) and the elastic repulsion force (F _R ) by the elastic member with only the repulsive forces alone The position is provided in the position which becomes 1/3 of a contact base.

Repulsion, Breaker, Korean Wave, Challenge

Description

Current-limit structure of current-limiting conductive part {CURRENT-LIMIT STRUCTURE OF CURRENT-LIMIT TYPE CONTACTOR}

The present invention relates to a current-limiting structure of a current-limiting conductive part. More specifically, the current-limiting current-limiting part of a current-limiting conductive part is capable of quickly tripping and extinguishing the drive of the tripping device only by contact between the contacts and structural repulsive force. It's about structure.

In general, a circuit breaker is a wiring facility used for protecting an industrial plant or a generator for protecting a generator.

The breaker is provided with a fixed contactor and a movable contactor, and the movable contactor is brought into contact with each other to conduct electricity. At this time, if a large current flows due to a failure at any position on the line, the moving contactor is disconnected from the fixed contactor to cut off the current.

Such breaker should cut off the current quickly to protect the breaker in case of accidental current exceeding the specified current generated in the line.

However, the conventional circuit breaker has a drawback in that it takes a lot of time to trip and extinguish when the accident current is sensed, and the trip and extinguish by driving a trip device that separates the fixed contactor and the movable contactor.

SUMMARY OF THE INVENTION The present invention has been made in view of the above necessity, and an object thereof is to provide a current-limiting structure of a current-limiting conductive part that can be quickly tripped and extinguished prior to driving of a trip device only by contact and structural repulsive force.

The current-limiting structure of the current-limiting conductive part of the present invention for achieving the above object is provided with a fixed fixed terminal having a fixed contact point, and a movable contact coupled to the contact base to be rotatable to the contact base to have an elastic force in one direction. And a breaker having a movable terminal hinge-coupled such that the contact base can be driven by a trip device having a “U” shape, and in response to an electromagnetic repulsion force F _L due to the “U” shape structure during an accident current. , The repulsive force combined with the contact repulsion force (Fs) by the fixed contact point and the movable contact, the attraction force combined with the compensatory repulsion force (Fc) according to the electromagnetic repulsion force (F _L ) and the elastic repulsion force (F _R ) by the elastic member with only the repulsion forces And the position of the working shaft to be 1/3 of the contact base so as to be extinguished.

As described above, the repulsive force obtained by adding the electromagnetic repulsive force (F _L ) by the "U" shaped structure, the contact repulsive force (Fs) by the fixed contact point and the movable contact point, the compensation repulsive force (Fc) according to the electromagnetic repulsive force (F _L ), and The current-limiting structure of the current-limiting conductive part of the present invention, which enables tripping and extinguishing according to the elastic resilience force (F _R ) by the elastic member, has an effect of improving reliability according to the current-limiting conductive part.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings.

In describing the present invention, the defined terms are defined in consideration of the function of the present invention, and should not be understood in a limiting sense of the technical elements of the present invention.

1 is a schematic view showing a circuit breaker having a current-limiting structure of a current-limiting conductive part according to an embodiment of the present invention. 2 is a characteristic diagram illustrating a circuit breaker having a current-limiting structure of a current-limiting conductive part according to an embodiment of the present invention.

As shown in FIG. 1, the current-limiting conductive part of the present invention includes a fixed terminal 10 having a fixed contact 11 provided at one end thereof, and a contact base having a movable contact 21 coupled to a working shaft 22a. 22 is composed of a movable terminal 20 which is hinged. The movable contact 21 includes an elastic member 23 that provides an elastic force in the direction of the fixed contact 11 with the working shaft 22a as the rotation axis. Therefore, in the case of the normal current maintains a contact state with the fixed contact 11 with a constant elastic force.

At this time, the fixed terminal 10 and the movable terminal 20 are installed side by side parallel to each other, the contact base 22 is hinged to one end of the movable terminal 20. In this case, the contact base 22 is provided to support the movable contact 21. The movable contact 21 and the movable terminal 20 are electrically connected to each other.

Therefore, the contact terminal 22 and the movable contact 21 in which the fixed terminal 10 and the fixed contact 11 and the fixed contact 11 are in contact with and spaced apart from each other, and the movable contact 21 are coupled to the working shaft 22a. In addition, the movable terminal 20 to which the contact base 22 is hinged is provided to have a "U" shape in a state in which the movable contact 21 and the fixed contact 11 are in contact with each other.

This "U" -shaped structure is generated by the electromagnetic repulsive force (F _L ) by the electromagnetic force. In addition, the contact repulsion force (Fs) according to the contact is generated in the fixed contact 11 and the movable contact (21). Herein, the electromagnetic repulsive force F _L and the contact repulsive force Fs vary in magnitude depending on the strength of the current flowing through the “U” shaped structure. Therefore, the electromagnetic repulsive force (F _L ) and the contact repulsive force (Fs) acts as a repulsive force trying to separate between the contacts.

In addition, a compensation repulsive force (Fc) is generated to compensate for this when the electronic repulsive force (F _L ) occurs. The compensation repulsive force (Fc) is a force acting on the opposite side of the movable contact 21 that is in contact with the fixed contact 11 around the working axis (22a) in the contact base 22 is opposite to the electromagnetic repulsive force (F _L ) Force is at work.

And there is an elastic repulsive force (F _R ) generated from the elastic member (23). The elastic repulsive force (F _R ) is determined by the elastic force of the elastic member 23 is determined to have an appropriate elastic force. Therefore, the compensatory resilience force Fc and the elastic resilience force F _R act as an attractive force between the contacts.

Here, the sum of the contact repulsive force (Fs) and the electromagnetic repulsive force (F _L ) acting as the repulsive force is less than the sum of the compensatory reaction force (Fc) and the elastic repulsive force (F _R ) acting as the attractive force (Fs + F _L <Fc + F _R) the movable contact 21 and fixed contact 11 are spaced apart, the greater (Fs + _L F> Fc + F _R) and the movable getting fixed contact 11 is contacted.

At this time, the position of the working shaft 22a is 1/3 of both ends of the contact base 22, that is, the entire length of the contact base 22 is divided into three parts as shown in FIG. When provided at the upper third point of the contact base 22 in the direction, as a result, the movable contact 21 is directed toward the fixed contact 11, thereby compensating for the excessive electromagnetic repulsive force F _L.

As shown in FIG. 2, the repulsive point (Xr: Retrated Position) means a state in which the contact point is slightly separated by the contact repulsion force (Fs), and is required for maximizing the current-limiting performance through ultra-fast opening. . The movable contact 21 maintains the rebound point Xr while the elastic member 23 of the movable contact 21 for the high speed opening is compressed.

In addition, the arc generated at the repulsion point is driven by the magnetic field flows into the SOHO grid to increase the arc voltage, and when the arc voltage rises above the power supply voltage, a current limit is generated.

At this point, it is important to determine the limiting threshold current value Il and the disengagement threshold current value Ic.

Here, the limiting threshold current value Il is a current value that the contact opens, and usually corresponds to a short time current value, and the sum of the contact repulsion force (Fs) and the electron repulsion force (F _L ) is the elastic resilience force (F _R). ) Is equal to the sum of the compensation repulsive force (Fc).

The disengagement threshold current value Ic is a current value at which the elastic member 23 is driven and is determined to be about 110% of the normal electric current value.

Therefore, when looking at the operation sequence by time, at time t1, the contact repulsion force (Fs) is greater than the elastic repulsion force (F _R ) by the elastic member 23, the movable contact 21 starts to move, and gradually with the opening of two points An arc voltage Uarc is generated by an arc between them. The current at this time corresponds to the threshold threshold current value Il.

The arc voltage also increases during the period from time t1 to t2, wherein the increase in the arc voltage is increased by the extension of the length of the arc.

At t2, the spacing between the contacts is also sufficiently dropped and the magnetic velocity is increased by the lower U-shaped structure, so the arc rapidly arrives at the SOHO grid, and the arc voltage Uarc is rapidly increased by the SOHO grid.

At t3, the movable contact 21 is positioned at the maximum moving position due to the contact repulsion force Fs, i.e., the retrated position Xr.

At t4, the current reaches the Disengagement Threshold current value Ic and the movable contact starts to move. While the movable contact compresses the spring, the contact does not move and the repulsion point is maintained.

That is, the contact repulsion force (Fs), the electromagnetic repulsion force (F _L ), the compensation repulsion force (Fc) is increased to each of the current is transmitted to the spring to compress the spring.

At t5, the arc continues to elongate in the extinguishing portion, causing the arc voltage Uarc to be greater than the power supply voltage, causing a current limit.

The trip device, not shown at t6, is activated. At this time, the operation of the mechanism should occur when the current decreases, so that the opening operation is relatively slow, and the stress of the other components is less stressed in the operation of the trip device, thereby improving the reliability of the product.

Therefore, in order to operate correctly as described above, it is important to adjust the force of the spring so that the movable contact 21 operates correctly at the threshold threshold current value Il and the release threshold current value Ic.

1 is a schematic view showing a circuit breaker having a current-limiting structure of a current-limiting conductive part according to an embodiment of the present invention.

Figure 2 is a characteristic view showing the characteristics of a circuit breaker having a current-limiting structure of the current-conductive portion according to an embodiment of the present invention.

Claims (1)

A fixed fixed terminal having a fixed contact point, and a movable contact coupled to the contact axis to be rotatable to the contact base but having an elastic member to have elastic force in one direction, and the contact base is hinged to be driven by the trip device. In the current-limiting structure of the current-limiting conductive portion of the circuit breaker such that the movable terminal has a "U" shaped structure, Compensation reaction force (Fc) and elastic member according to electron reaction force (F _L ) by repulsive force that combines the electromagnetic repulsion force (F _L ) by the "U" shaped structure and the contact repulsion force (Fs) by the fixed contact and the movable contact during an accident current. It is characterized in that the position of the working shaft is provided at a position that is 1/3 of the upper side close to the fixed terminal in the entire length of the contact base so that the attraction force combined with the elastic repulsion force (F _R ) by the repulsion force can be tripped and extinguished with only the repulsive forces. Current-limiting structure of current-limiting conductive parts.

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