JPH03182028A - Circuit breaker - Google Patents

Abstract

PURPOSE:To heighten contact parting speed and current-limiting performance and to lengthen a contact parting space by providing at least two sets of an electromagnetic repulsion mechanism which rotatively actuates current-limiting contact bases with its electromagnetic repulsive force as a couple of forces generated at both sides of each turning center of the current-limiting contact bases. CONSTITUTION:When a large current flows in a breaker through a contact base 15 due to a short-circuit accident, electromagnetic repulsive force is generated by a short- circuit current in two position between the contact base 15 and an end part 12a of a current-limiting contact base 12, and between a current-limiting contact base 12b part of the opposite side of a pin 17 as turning center of the contact base 12 and a movable contact base 9. As a result, the base 12 is turned counterclockwise around the pin 17 and opened at high speed. Since the electromagnetic repulsive force is also generated in the positions between the current-limiting contact base 15 and an end part 22b of a current-limiting contact base 22, and between an end part 22a and the fixed contact side of a contact base 23, the base 22 is turned clockwise around a pin 21 and opened at high speed. After completion of breaking action, the bases 12, 22 are returned by springs 13, 21 to the original position to make switching mechanism effective.

Description

[Detailed Description of the Invention] [Field of Industrial Application] The present invention relates to a circuit breaker, and in particular to a current limiting circuit breaker having an electromagnetic repulsion mechanism, by increasing the opening speed and increasing the opening distance of a contact block. The present invention relates to a circuit breaker suitable for improving current limiting performance.

[Conventional technology]

A current-limiting circuit breaker is a device that limits large fault currents such as those caused by short circuits to a small value and interrupts them without directly processing them.Not only does the circuit breaker itself have a high breaking capacity, but it also greatly reduces the peak value of the passing current. It has the advantage of being able to reduce the electromagnetic and thermal shock that is applied to circuit equipment, electric wires, etc., since it can be limited to a short period of time and is shut off for a short time. As a conventional device of this type, there is one disclosed in Japanese Utility Model Application Publication No. 52-45164, for example, but it is necessary to reduce the dimension between the conductors in order to generate electromagnetic repulsion between the movable contact block and the current-limiting contact block. It was not possible to do so, and the length was also limited. Also, Jikko Sho 55-8
The device disclosed in Japanese Patent No. 835 includes a set of electromagnetic repulsion mechanisms.

[Problem to be Solved by the Invention 'd1] The above-mentioned conventional technology is not sufficient in terms of electromagnetic repulsion, and further improvement in performance is desired.

In view of the above-mentioned problems, an object of the present invention is to provide a circuit breaker equipped with an electromagnetic repulsion mechanism that further improves the opening speed, has a long opening distance, and has excellent current limiting performance.

[Means for Solving the Problems] The above object is provided with at least two sets of electromagnetic repulsion mechanisms that rotate the current-limiting contact base using electromagnetic repulsion forces generated on both sides of the center of rotation of the current-limiting contact base as a couple. Accomplished by a circuit breaker.

[Function] In the above configuration, when a short-circuit current flows during interruption, an electromagnetic repulsive force is generated in the first current-limiting contact block and the second current-limiting contact block, which acts as a couple with respect to the center of rotation, and the circuit breaker Electromagnetic repulsion mechanisms for opening can be provided at two locations, which increases the opening speed of the current limiting contact block and increases the arc voltage, greatly enhancing the current limiting effect.

[Example] An example of the present invention will be described below with reference to FIGS. 1 to 3.

Fig. 1 is a side cross-sectional view showing an embodiment of the circuit breaker according to the present invention in the ON state, Fig. 2 is a front view of the main part showing the breaking operation process, and Fig. 3 is a front view of the main part showing the circuit breaker after completion of breaking. It is a diagram. 1st
In the figure, the 0N-OFF operation is performed by moving the movable contact block by opening and closing the operating handle 3 protruding from the top surface of the mold cover 2 in the "○N" direction or the "OFF" direction. By moving the switch to the power source side, the two-bar link of the opening/closing mechanism 4 having a toggle link mechanism works, and the interlocking shaft 7, which is located at one end of the opening/closing mechanism section 4 and supports the movable contact block 9 with three poles, is activated. Rotate. As a result of this counterclockwise rotation of the interlocking shaft 7, the entire movable contact base 9 moves around the bin 16, and as a result, the movable contact 10 located at one end of the movable contact base 9 moves away from the movable contact base 9. It is arranged at the lower part of the switchgear sliding part 4 in a direction facing the current-limiting contact base 9 having the current-limiting contact 11 at one end so as to move to the position of the current-limiting contact 11 that comes into contact with it.

The rotation center of the first current-limiting contact base 12 is supported by a pin 17, and the pin 17 is provided with a return spring 13 that biases the first current-limiting contact base 12 clockwise. One end of the return spring 13 is locked to the molded case 1, and the other end is locked to the first current-limiting contact block 12.
It is engaged with the opposite side 12a of the bottle 17, which is the center of rotation.

A flexible twisted wire 14 is attached to one end of the first current-limiting contact block 12a.
is connected, and its extension is connected to one end of the second contact base 23.

A fixed contact 24 is arranged at the other end of the second contact stand 23, and a movable contact 25 is arranged on the second current-limiting contact stand 22 supported by the bottle 21 so as to be in contact with the fixed contact 24. The bottle 21 is provided with a spring 26 that biases the second current-limiting contact base 22 in a counterclockwise direction.

Regarding the bottle 21, the movable contact 25 of the second current-limiting contact base 22
A flexible stranded wire 14 is connected to the opposite end thereof, and its extension is connected to one end of the first contact base 15. The first current-limiting contact base 12 is rotatable around the bin 17, and the movable contact base 9 and the first current-limiting contact base 12, and the second current-limiting contact base 22 and the first contact base 15 each have an electromagnetic force. It is arranged and configured to rotate in the direction of repulsion, that is, in the direction of the couple.

Further, the second current-limiting contact base 22 is rotatable around the bin 21, and the first contact base 15, the second current-limiting contact base 22, and the second
The contact base 23 and the second current-limiting contact base 22 are each configured to similarly rotate in the couple direction by electromagnetic force.

To detect overcurrent, the movable iron piece 19, which has an oil dashpot portion 5 and is attracted by the rise of the plunger, causes a mechanism portion to trip.

As shown in the operation process diagram of FIG. 2, when a large current flows into the circuit breaker via the first contact block 15 due to a short circuit accident, as described above, the first contact block provided oppositely 15 and 1st
The first current-limiting contact base 12b of the contact portion located between the end portion 12a of the current-limiting contact base 12 and the opposite side of the bin 17, which is the center of rotation of the first current-limiting contact base 12, and the movable contact base. 2 between 9
An electromagnetic repulsive force is generated by the short-circuit current at the location, and as a result, the first current-limiting contact block 12 rotates counterclockwise about the pin 17 and opens at high speed. In addition, the first contact base 15
and the opposite end 22b of the second current-limiting contact base 22, and regarding the center of rotation of the second current-limiting contact base 22, the end 22
An electromagnetic repulsive force is generated between the end 22a on the opposite side of b and the fixed contact side of the second contact block 23, and the second current-limiting contact block 22 rotates clockwise around the bottle 21. Released at high speed. When the interrupting operation is completed, the first current-limiting contact block 12 and the second current-limiting contact block 22 are returned to their original positions by the springs 13, 21, and the opening/closing mechanism is activated to enter the state shown in FIG. 3.

According to this embodiment, the opening speed of the current-limiting contact block is greatly improved, and the arc voltage is further doubled by the two current-limiting contact blocks, so that the current-limiting performance is greatly improved.

Another embodiment is shown in Figure 4.5. FIG. 4 is a front view of the main part showing the shutoff operation process of another embodiment of the present invention, and FIG. 5 is a front view of the main part showing the other embodiment after the cutoff is completed. Components having the same reference numerals as those in the drawings are the same functional parts. In FIG. 4, the electromagnetic repulsive force acting on the second current-limiting contact base 22 is limited to one direction on the portion facing the second contact base 18 on the opposite side of the bottle 21. This embodiment differs from the embodiments of FIGS. 1 to 3 in that the first contact base 15 and the second contact base 18 are directly connected to each other. The electromagnetic repulsive force is generated between the first current-limiting contact base 12 and the first contact base 15, and between the second contact base 18 and the second contact base 15.
The circuit breaker is actuated at two locations between the current limiting contact block 22 and the circuit breaker is opened, and the function is equivalent to that of the embodiment shown in FIGS. 1 to 3. The state in which the cut-off is completed is shown in FIG.

As mentioned above, the present invention employs a plurality of pairs of electromagnetic repulsion structures using couple forces, and connects the contacts and the opposite end of the current-limiting contact block by a flexible mPA, and connects the contacts on both sides of the rotation center of the current-limiting contact block. Since no contacts are provided, the distance between the conductors can be reduced, and more than twice the arc voltage can be obtained without interfering with the electromagnetic repulsion operation of the current-limiting contact block. In addition to superior breaking performance with significantly increased speed, a compact circuit breaker can be provided.

〔Effect of the invention〕

By using the circuit breaker of the present invention, the opening speed of the contact block at the time of interruption is increased, and the electromagnetic repulsion mechanism provided at multiple locations increases the opening distance and increases the arc voltage. This has remarkable effects such as a dramatic improvement in flow performance.

[Brief explanation of drawings]

Fig. 1 is a side sectional view of an embodiment of the circuit breaker according to the present invention in the ON state, Fig. 2 is a front view of main parts showing the breaking operation process of the embodiment shown in Fig. 1, and Fig. 3 is the same as Fig. 2. FIG. 4 is a front view of the main part showing the shutoff operation process of another embodiment of the present invention, and FIG. 5 is a front view of the main part showing after the cutoff of the embodiment shown in FIG. It is a front view.

Claims (1)

[Claims] 1. In a circuit breaker having an electromagnetic repulsion mechanism caused by currents flowing in opposite directions between a movable contact block and a current-limiting contact block,
A circuit breaker comprising at least two sets of electromagnetic repulsion mechanisms that rotate the current-limiting contact block using electromagnetic repulsion forces generated on both sides of the center of rotation of the current-limiting contact block as a couple. 2. The electromagnetic repulsion mechanism includes a movable contact base, a first current-limiting contact base having a contact that comes into contact with the movable contact base, and an end opposite to the contact with respect to the rotation center of the first current-limiting contact base. a first contact base having opposing ends; a first electromagnetic repulsion mechanism that rotates the first current-limiting contact base using a couple of electromagnetic repulsion forces generated on both sides of the rotation center; and a second current-limiting contact. a second contact base having a contact that comes into contact with the second current-limiting contact base, and an end of the contact opposite to the rotation center of the second current-limiting contact base is connected to the end of the first contact base; Claim 1, characterized in that it consists of a second contact block facing each other and a second electromagnetic repulsion mechanism that rotates using electromagnetic repulsion forces generated on both sides of the center of rotation of the second current-limiting contact block as a couple. A circuit breaker as described in . 3. The second electromagnetic repulsion mechanism has a second current-limiting contact base, and an end opposite to the opposite end of the contact with respect to the rotation center of the second current-limiting contact base is the first electromagnetic repulsion mechanism. The circuit breaker according to claim 2, wherein the circuit breaker is connected to an end of the first contact block.