JPH0697587B2 - Circuit breaker - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention provides first and second movable contacts that are normally in contact with each other between the first and second movable contacts based on an accident current. The present invention relates to a circuit or a breaker configured to separate from each other by utilizing electromagnetic repulsive force.

[Technical Background of the Invention and Problems Thereof] A circuit breaker and a circuit breaker basically have a structure in which a trip device displaces a movable contact from a closed position to an open position to close a main circuit when an overcurrent is detected. Is. However, in recent years, in order to improve the breaking performance, the first device is displaced by the trip device.
In addition to the movable contactor, the second movable contactor is provided so as to be constantly in contact with the first movable contactor in the closed position, and the accident current causes the first and second movable contactors to be provided. There is one in which the first movable contactor and the second movable contactor are rotated in the directions away from each other by utilizing the electromagnetic repulsive force when they flow in opposite directions. In addition, as shown in JP-A-59-108231,
A plunger relay including a coil and a plunger is provided in the vicinity of the first and second movable contacts, and the displacement of the plunger caused by the fault current flowing through the coil causes the first movable contact to move to the second movable contact. It is considered that the accident current is limited by forcibly rotating the movable contact in a direction away from the movable contact. The specific configuration of this is as shown in FIGS. 4 and 5. First, in FIG. 4, reference numeral 1 is an operation handle provided on the case 2, and 3 is a first movable contactor whose one end is pivotally supported by a support plate 4 by a shaft 5. The child 3 is biased in the counterclockwise direction in the drawing by a tension coil spring 6 stretched between an intermediate portion of the child 3 and the support plate 4. Reference numeral 7 is a well-known toggle mechanism provided between the operation handle 1 and the first movable contactor 3, and 8 is a trip device, which trip device 8 detects an overcurrent in the main circuit. Latch 9 catch 10
By releasing the locking of the first movable contactor 3, the first movable contactor 3 is allowed to rotate from the closed position shown in the drawing to the closed position not shown in the drawing rotated clockwise. Reference numeral 11 denotes a second movable contactor 3 provided below the first movable contactor 3 along the second movable contactor 3.
Of the movable contactor, one end of which is pivotally supported by the support portion 12 by the shaft 13 and the other end of which is always in contact with the contact 3a of the first movable contactor 3 by the compression coil spring 14. The main circuit is closed. Reference numeral 15 is a fixed conductor which constitutes a power supply side terminal, and this and the second movable contactor 11
And are connected by a flexible conductor 16. Reference numeral 17 denotes a plunger type relay provided above the first movable contactor 3, which is provided with a coil 18 and a plunger 20 provided vertically movable in the container 19, of which the coil 18 has one end. Is connected to the first movable contactor 3 by a flexible conductor 21 and the other end is connected to the trip device 8, and the lower part of the plunger 20 penetrates the middle part of the first movable contactor 3. In addition, the projection 22 is formed at the lower end thereof. Reference numeral 23 is an arc extinguishing device for extinguishing the arc generated between the first and second movable contacts 3 and 11.

In this configuration, when a large fault current such as a short circuit current flows in the main circuit, the first and second movable contacts 3 and 11
Since currents flowing in directions opposite to each other flow as indicated by arrows in the figure, an electromagnetic repulsive force is generated between the first and second movable contacts 3 and 11. Further, in the plunger type relay 17, the plunger 20 is pulled upward in the drawing due to the fault current flowing through the coil 18. Therefore, prior to the opening operation of the first movable contactor 3 based on the operation of the trip device 8, the electromagnetic repulsive force causes the first movable contactor 3 to move to the fifth position.
As shown in the drawing, the second movable contact 11 rotates in the clockwise direction around the shaft 5 against the biasing force of the tension coil spring 6, and the second movable contact 11 resists the biasing force of the compression coil 14 to rotate the shaft 13. Rotate counterclockwise around, while the plunger relay 17
The movement of the plunger 20 causes the projection 22 at the lower end of the plunger 20 to hit the first movable contactor 3 and forcibly rotate it in the clockwise direction. Then, an arc is generated between the first and second movable contactors 3 and 11 based on the rotations of the first and second movable contactors 3 and 11 so that they are separated from each other, whereby a large current is generated. The arc is extinguished by the arc extinguishing device 23 while the arc extinguishing device 23 is extinguished, and the tripping device 8 is subsequently operated to displace the first movable contactor 3 to the open circuit position to completely open the main circuit. .

However, in the case of such a configuration, the first movable contact 3 is rotated in the direction away from the second movable contact 11 by the electromagnetic repulsive force and the operation of the plunger type relay 17, but the second movable contact 3 is moved. The contactor 11 rotates in a direction away from the first movable contactor 3 only by the electromagnetic repulsive force. For this reason,
Since the electromagnetic repulsive force decreases as the distance between the first and second movable contactors 3 and 11 opens, the second movable contactor 11 approaches the first movable contactor 3 by the spring force of the compression coil spring 14. In this case, since currents flowing in the second movable contact 11 and the fixed conductor 15 in opposite directions flow to each other, the second movable contact 11 and the fixed conductor 15 have a tendency to return in the same direction.
An electromagnetic repulsive force is also generated between the second movable contactor 11 and the second movable contactor 11, and the second movable contactor 11 also tends to rotate in a direction approaching the first movable contactor 3, and therefore the breaking performance in the event of an accident current is generated. There was a drawback that it could not be improved.

[Object of the Invention] The present invention has been made in view of the above circumstances, and an object of the present invention is to provide first and second movable contacts that rotate in a direction in which they are separated from each other by an electromagnetic repulsive force based on an accident current. It is an object of the present invention to provide a circuit and a circuit breaker that can be held in a separated position until the circuit is completely cut off, and thus can improve the breaking performance when an accident current occurs.

SUMMARY OF THE INVENTION The present invention is directed to a direction in which the first movable contactor and the second movable contactor are separated from each other by an electromagnetic repulsive force generated between the first and second movable contactors based on an accident current. In a circuit or breaker that is made to rotate, a plunger relay including a coil and a plunger is provided in the vicinity of the first and second movable contactors, whereby the coil of the plunger relay has a fault current. The first movable contactor is rotated in the direction away from the movable contactor of FIG. 2 by the displacement of the plunger due to the flow of the second movable contactor, and the second movable contactor is moved away from the first movable contactor. It is characterized by being rotated.

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. However, the same parts as those of the conventional configuration are designated by the same reference numerals and detailed description thereof will be omitted. That is, in FIG. 1, 1 is an operating handle, 2 is a case, 7 is a toggle mechanism, 8 is a tripping device, 9 is a latch, 10 is a catch, 15 is a fixed conductor, and 23 is an arc extinguishing device.

Now, 24 is a first movable contactor, one end of which is pivotally supported by a support plate 25 by a shaft 26, which has an intermediate portion and a support plate 25.
A tension coil spring 27 stretched between and is urged in the counterclockwise direction in the figure. 28 is the first movable contact 24
The second movable contactor is provided below and along the same, the middle portion is pivotally supported by the support portion 29 by the shaft 30, and the left end portion in the figure is always contacted by the compression coil spring 31. 28
A is urged to contact the contact 24a of the first movable contact 24 to close the main circuit. The intermediate portion of the second movable contactor 28 and the fixed conductor 15 are connected via a flexible conductor 32. 33 is a plunger type relay provided in the vicinity of the first and second movable contacts 24 and 28, and in this case above the first movable contact 24, which is provided on the coil 34 and the container 35 so as to be vertically movable. And a plunger 36. Of these, the coil 34 has a flexible conductor on one end of which is attached to the first movable contact 24.
The other end is connected to the trip device 8 via 37. Further, the plunger 36 has a lower movable contact 24.
On the left side of the shaft 26 and on the second movable contact 28
A first protrusion 38 is formed on the lower side of the first movable contact 24 through the right side of the second movable contact 24, and a second protrusion 39 is formed on the lower side of the second movable contact 28. Are formed. In such a plunger type relay 33, the plunger 36 is displaced upward in the drawing due to the fault current flowing through the coil 34, so that the first protruding portion 38 has the first protruding portion 38 as shown in FIG. The movable contactor 24 is rotated in the clockwise direction and the second projection 39 is contacted with the second movable contactor 28 to rotate it in the counterclockwise direction. The first movable contact 24 is rotated in a direction away from the second movable contact 28 by the displacement of the plunger 36 due to the flow of the current, and the second
The movable contactor 28 is rotated in a direction away from the first movable contactor 24.

In the above structure, when a large fault current such as a short-circuit current flows in the main circuit, currents in opposite directions flow in the first and second movable contacts 24, 28 as indicated by arrow A in FIG. As a result, an electromagnetic repulsive force is generated between the first and second movable contacts 24, 28, while in the plunger type relay 33, the plunger 36 is moved by the arrow B in FIG. By being displaced in the direction, the first protrusion 38 of the plunger 36 becomes the first movable contactor.
The first movable contactor 24 is contacted with the second movable contactor 28 by rotating the first movable contactor 24 in a direction away from the second movable contactor 28, and the second protrusion 39 contacts the second movable contactor 28. 28 is rotated in a direction away from the first movable contact 24. Therefore, the first movable contact 24 rotates in the direction away from the second movable contact 28 against the spring force of the tension coil spring 27, while the second movable contact 28 moves in the compression coil spring. It rotates in the direction away from the first movable contact 24 against the spring force of 31. Even if the first and second movable contacts 24, 28 are separated by this separating operation, the accident current continues to flow while being limited by the arc generated between the contacts 24a, 28a (see FIG. 2). In this case, since the plunger 36 in the plunger type relay 33 is displaced in the direction of arrow B while the fault current flows through the arc, the first and second protrusions 38, 39 of the plunger 36 cause The first and second movable contacts 24 and 28 are held in the separated positions, respectively. After that, when the trip device 8 is activated and the first movable contact 24 is displaced to the open circuit position together with the support plate 25 by the toggle mechanism 7 as shown in FIG. 3, the arc voltage sharply rises. The accident current is completely cut off.
As a result, the plunger of the plunger relay 33 is
When 36 moves in the direction opposite to the arrow B and returns to the original position, the first movable contact 24 is rotated by the urging force of the tension coil spring 27 toward the second movable contact 28, and The second movable contact 28 is rotated toward the first movable contact 24 by the biasing force of the compression coil spring 31. In this case, even if the first and second movable contacts 24, 28 rotate in the direction in which they approach each other in this way, the first movable contact 24 is displaced to the open circuit position together with the support plate 25. The first and second movable contacts 24 and 28 do not come into contact with each other, and therefore the main circuit is never closed.

As described above, according to this embodiment, the first and second electromagnetic repulsive forces based on the accident current are generated without waiting for the operation of the trip device 8.
The movable contacts 24, 28 of the above are rotated in a direction in which they are separated from each other, and the plunger relay 33 also causes the first and second
Since the movable contactors 24 and 28 are rotated in the directions in which they are separated from each other, only the first movable contactor 3 is forced to separate from the second movable contactor 11 by the plunger relay 17. Unlike the conventional structure in which the second movable contact 28 is rotated, the second movable contact 28 is moved to the first position by the compression coil spring 31.
It is possible to prevent the tendency of the second movable contact 24 to return to the direction closer to the movable contact 24, and even if there is a situation where an electromagnetic repulsive force is generated between the second movable contact 28 and the fixed conductor 15, It is possible to prevent the contact 28 from rotating toward the first movable contact 24, so that the first and second movable contacts 24, 28 are separated from each other until the main circuit is completely cut off. Therefore, it is possible to improve the blocking performance.

In the above embodiment, the plunger 36 of the plunger type relay 33 pulls up the first and second movable contacts 24, 28 so that the first and second movable contacts 24, 28 are separated from each other. However, instead of this,
For example, the plunger of the plunger type relay may push down the first and second movable contacts to rotate the first and second movable contacts in directions away from each other. The present invention can be appropriately modified and implemented without departing from the above.

[Effects of the Invention] As is clear from the above description, in the present invention, the main circuit completely shuts off the first and second movable contacts that rotate in the directions in which they are separated from each other by the electromagnetic repulsive force based on the accident current. It has an excellent effect that it can be held in the separated position until it is stopped, and thus the breaking performance at the time of occurrence of an accident current can be improved.

[Brief description of drawings]

1 to 3 show an embodiment of the present invention. FIG. 1 is an overall vertical cross-sectional view, and FIG. 2 is an enlarged view of the essential parts showing the separating operation state of the first and second movable contacts. FIG. 3 is a longitudinal sectional view showing the state in which the first movable contact is displaced to the open circuit position. 4 and 5 show a conventional structure, FIG. 4 is a view corresponding to FIG. 1, and FIG. 5 is a view corresponding to FIG. 1 showing a separating operation state of the first and second movable contacts. is there. In the drawing, 8 is a trip device, 24 is a first movable contact, 26 is a shaft, 28 is a second movable contact, 30 is a shaft, 33 is a plunger relay, 34 is a coil, 36 is a plunger, 38 Is a first protrusion and 39 is a second protrusion.

Claims (1)

[Claims] 1. A first movable contact which is rotatably pivotally supported and is displaceable from a closed position to an open position by a trip device when an overcurrent is detected, and the first movable contact which is pivotally supported and is in the closed position. A second movable contactor which is urged to always contact the first movable contactor, and the electromagnetic repulsive force generated between the first and second movable contactors based on an accident current causes the first movable contactor to move.
In which the movable contactor and the second movable contactor are rotated in directions away from each other, and a coil and a plunger are provided in the vicinity of the first and second movable contactors. The first movable contactor is rotated in the direction away from the second movable contactor by the displacement of the plunger due to the flow of the accident current in the second movable contactor and the second movable contactor is separated from the first movable contactor. A circuit breaker or breaker characterized by having a plunger relay that rotates in the direction of rotation.