JP2014238934A - Circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a compact circuit breaker having high cut-off performance.SOLUTION: A circuit breaker includes: a stationary contactor 12 in which a stationary contact point 11 is provided; a movable contractor 14 in which a movable contact point 13 contactable with the stationary contact point 11 is provided; an arc dividing means 18 for dividing arc 20 generated between the stationary contact point and the movable contact point during the opening operation into two arcs 21, 22; and first and second arc-extinguishing devices 16A, 16B, each of which has a plurality of magnetic grids 17 arrayed at a prescribed interval in one direction, and which individually extinguish arcs after being divided by the arc dividing means.

Description

  The present invention relates to a circuit breaker such as a circuit breaker for wiring or an earth leakage breaker.

Circuit breakers such as circuit breakers for wiring and earth leakage circuit breakers are used in order to cut off the short-circuit current flowing in the load circuit or the overcurrent of the overload current. In this type of circuit breaker, as disclosed in Patent Document 1, an arc generated between the stationary contact of the stationary contact and the movable contact of the movable contact during the opening operation is extinguished by the arc extinguishing device. What is arcing is known.
9 to 11 show an example of a current breaker of a conventional circuit breaker that extinguishes an arc generated between the fixed contact of the fixed contact and the movable contact of the movable contact during the opening operation by the arc extinguishing device. FIG. 9 is a cross-sectional view of a main part, FIG. 10 is a perspective view showing an extracted current interrupting part, and FIG. 11 is a side view showing an extracted current interrupting part.

As shown in FIG. 9, a conventional circuit breaker 60 has an overcurrent detection mechanism (not shown) for detecting an overcurrent in one insulating container composed of a case 61 and a cover 62, thereby opening a movable contact. The structure includes a movable contact opening mechanism (not shown) for making a pole, and a current interrupting section 50 for rapidly limiting the current flowing in the short circuit to interrupt the current.
As shown in FIGS. 9 to 11, the current interrupting unit 50 includes a fixed contact 52 provided with a fixed contact 51, a movable contact 54 provided with a movable contact 53 capable of contacting the fixed contact 51, and an open circuit. Arcs 55 (see FIG. 10 and FIG. 11) generated between the fixed contact 51 of the fixed contact 52 and the movable contact 53 of the movable contact 54 during pole operation are arranged in a layer at predetermined intervals in one direction. And an arc extinguishing device 57 for extinguishing the arc with a plurality of magnetic grids 56.

In the conventional circuit breaker 60, when the load current is energized, the fixed contact 52 and the movable contact 54 are closed, and the fixed contact 51 and the movable contact 53 are in contact with each other and the conduction state is maintained. Since the fixed contact 51 and the movable contact 53 are separated from each other during the OFF operation, an arc 55 is generated between them.
The arc 55 generated between the fixed contact 51 and the movable contact 53 eventually receives the current flowing through the fixed contact 52 and the movable contact 54, the electromagnetic force acting on the arc 55 and the magnetic grid 56, and FIG. 11 starts moving and bending in the direction of the magnetic grid 56.

When the arc 55 reaches the magnetic grid 56, it is divided by each magnetic grid 56, whereby the voltage generated between the fixed contact 52 and the movable contact 54 increases at a stretch, and the current flowing through the short circuit is rapidly limited. The current is cut off.
Here, the voltage generated between the stationary contact 52 and the movable contact 54 is affected by the current value, the diameter of the arc 55, the number of the magnetic grids 56, and the like. The voltage per section of the magnetic grid 56 is about 25V. For example, when eight magnetic grids 56 are arranged in one direction as shown in FIG. 11, the voltage is generated between the fixed contact 52 and the movable contact 54. The voltage is about 225V. The voltage generated between the fixed contact 52 and the movable contact 54 is a counter electromotive force with respect to the power supply voltage.

Therefore, the conventional circuit breaker 60 can quickly limit the current flowing through the short circuit as the voltage generated between the fixed contact 52 and the movable contact 54 is higher, and from the occurrence of an accident current to the completion of the break. Can be shortened.
Further, the conventional circuit breaker 60 can increase the voltage generated between the fixed contact 52 and the movable contact 54 by increasing the number of the magnetic grids 56.

JP 2012-243659 A

However, as described above, the conventional circuit breaker 60 has an overcurrent detection mechanism, a movable contact opening mechanism, a current breaker 50, and the like housed in a single insulating container. It has a structure arranged in For this reason, the conventional circuit breaker 60 has a restriction on the height at which the current breaker 50 can be accommodated in the insulating container, and the number of magnetic grids 56 that can be arranged in one direction is limited. It was difficult to provide current limiting performance.
Therefore, the present inventor made the present invention paying attention to the arrangement of the magnetic grid.
The present invention has been made to solve such a conventional problem, and an object of the present invention is to provide a small circuit breaker having a high breaking performance.

  In order to achieve the above object, a circuit breaker according to one embodiment includes a fixed contact provided with a fixed contact, a movable contact provided with a movable contact capable of contacting the fixed contact, and an opening operation. Arc dividing means for dividing an arc generated between the fixed contact and the movable contact into a plurality of arcs, and a plurality of magnetic grids each arranged at a predetermined interval in one direction, And a plurality of arc extinguishing devices that individually extinguish the arcs divided by the arc dividing means.

  According to the circuit breaker according to this embodiment, the number of magnetic grids that can be arranged within a limited height dimension can be increased, and fixed contact can be made during opening operation within the limited height dimension. Since the voltage generated between the child and the movable contact can be increased, higher blocking performance can be obtained within a limited height dimension. As a result, a circuit breaker having a small size and a high breaking performance (high current limiting performance) can be obtained.

  Further, in the circuit breaker according to one embodiment, the arc dividing means divides the arc into a plurality of arcs by moving the arc generated between the fixed contact and the movable contact during the opening operation. An arc dividing portion, a first branch portion extending from the arc dividing portion toward a first arc extinguishing device of the plurality of arc extinguishing devices, and a plurality of arc extinguishing devices from the arc dividing portion. An intermediate electrode having a second branch portion extending toward the second arc extinguishing device adjacent to the first arc extinguishing device, and the first electrode from the tip side of the movable contact after the opening operation. The second arc extinguishing from a portion of the first arc runner extending toward the arc extinguishing device 1 and connected to the same potential as the movable contact and the fixed contact of the fixed contact A second arm extending towards the device A tip of the first arc runner on the first arc extinguishing device side and a tip of the first branch portion on the first arc extinguishing device side are the first arc extinguishing. A plurality of magnetic grids of the device spaced apart from each other in the arrangement direction, the second branch portion of the second arc extinguishing device side tip, and the second arc runner of the second arc extinguishing device side The tips are separated from each other in the arrangement direction of the plurality of magnetic grids of the second arc extinguishing device.

  According to the circuit breaker according to this one embodiment, among the arcs divided by the arc division part of the intermediate electrode, the arc on the movable contact side is divided by the first arc runner and the first branch part. The arc of the intermediate electrode can be easily guided to the first arc extinguishing device, and the arc on the fixed contact side among the arcs divided by the arc division of the intermediate electrode is changed to the second arc. The branch portion and the second arc runner can easily lead the arc split portion of the intermediate electrode to the second arc extinguishing device.

  The circuit breaker according to one embodiment further includes a partition that separates the first arc-extinguishing device and the second arc-extinguishing device, and the partition includes the first arc-extinguishing device and the first arc-extinguishing device. A first partition portion provided between the second arc-extinguishing device and the arc dividing portion of the intermediate electrode in the arrangement direction of the plurality of magnetic grids, located on the first arc runner side, A second partition wall portion provided so as to surround the second branch portion of the intermediate electrode and the second arc extinguishing device from the first partition wall portion; and the intermediate electrode in the arrangement direction of the plurality of magnetic grids. A third partition wall portion located on the fixed contact side of the arc dividing portion and provided so as to surround the first branch portion of the intermediate electrode and the first arc extinguishing device from the first partition wall portion. Have.

  According to the circuit breaker according to this one embodiment, the conductive gas generated on the first arc runner side with respect to the arc division portion of the intermediate electrode during the opening operation moves to the first arc extinguishing device side. The arc on the movable contact side among the arcs divided by the arc division part of the intermediate electrode, the electrode shape including the first arc runner and the first branch part of the intermediate electrode, and the second partition wall part By this action, it is possible to lead to the first arc extinguishing device more effectively.

  In addition, since the conductive gas generated on the stationary contact side of the arc division portion of the intermediate electrode during the opening operation moves to the second arc extinguishing device side, the arc of the arc after being divided at the arc division portion of the intermediate electrode Among them, the arc on the fixed contact side is more effectively converted into the second arc extinguishing device by the action of the electrode shape including the second branch portion of the intermediate electrode and the second arc runner and the third partition wall portion. Can lead.

  According to the present invention, it is possible to provide a small circuit breaker having a high breaking performance (high current limiting performance).

It is a perspective view which extracts and shows the electric current interruption part of the circuit breaker which concerns on one Embodiment of this invention. FIG. 2 is a perspective view in which a partition wall is not shown in the current interrupting section shown in FIG. It is a top view of the electric current interruption part shown in FIG. It is sectional drawing which follows the AA line of FIG. It is sectional drawing which follows the BB line of FIG. It is a side view of the electric current interruption part shown in FIG. It is sectional drawing which follows the CC line of FIG. It is sectional drawing which follows the DD line | wire of FIG. It is principal part sectional drawing which shows the electric current interruption part of the conventional circuit breaker. It is a perspective view which extracts and shows the electric current interruption part of the conventional circuit breaker. It is a side view which extracts and shows the electric current interruption part of the conventional circuit breaker.

Hereinafter, a circuit breaker according to an embodiment of the present invention will be described with reference to FIGS. 1 to 8. The arrows S shown in FIGS. 4, 5, 7 and 8 indicate the direction of arc movement to be described later.
First, the configuration of the circuit breaker will be described.
The circuit breaker according to the present embodiment is similar to the conventional circuit breaker 60 shown in FIG. And a current interrupting section 1 (see FIGS. 1 and 2) that shuts off the current by rapidly limiting the current flowing in the short circuit, and the like. .

As shown in FIGS. 1 to 8, the current interrupting unit 1 includes a fixed contact 12 provided with a fixed contact 11 and a movable contact 14 provided with a movable contact 13 capable of contacting the fixed contact 11. ing.
In addition, the current interrupting unit 1 is configured so that the arc 20 generated between the fixed contact 11 of the fixed contact 12 and the movable contact 13 of the movable contact 14 during the opening operation is divided into two arcs 21, An arc dividing means 15 for dividing the two arcs 22 and a first arc extinguishing device 16A and a second arc extinguishing device 16B for individually extinguishing the two arcs 21 and 22 divided by the arc dividing means 15; I have.

In addition, the current interrupting unit 1 includes a partition wall 24 that separates the first arc extinguishing device 16A and the second arc extinguishing device 16B.
The circuit breaker according to the present embodiment is configured such that the arc 20 generated between the fixed contact 11 of the fixed contact 12 and the movable contact 13 of the movable contact 14 during the opening operation is temporarily divided into two arcs 21 by the arc dividing means 15. The two arcs 21 and 22 divided by 22 and divided by the arc dividing means 15 are extinguished individually by the two arc extinguishing devices 16A and 16B.

Each of the first and second arc extinguishing devices 16A and 16B has a plurality of magnetic grids 17 arranged in a layer at a predetermined interval in one direction. The arc 20 generated between the fixed contact 11 of the fixed contact 12 and the movable contact 13 of the movable contact 14 is divided and extinguished. Here, the direction in which the plurality of magnetic grids 17 are arranged is referred to as a magnetic grid arrangement direction GL.
Each magnetic grid 17 is made of a magnetic material. Although not shown, each magnetic grid 17 is fixedly arranged at a predetermined interval by an insulating member. Although not shown in detail, each magnetic grid 17 is formed in a U shape or a V shape in which a pair of grid legs extend in parallel from the grid base.

Each of the first and second arc extinguishing devices 16A and 16B is arranged adjacent to each other in parallel when viewed in plan from the direction along the magnetic grid array direction GL.
The stationary contact 12 is made of a conductive material. The fixed contact 12 includes a first portion 12a provided with the fixed contact 11 and a final stage of the plurality of magnetic grids 17 of the second arc extinguishing device 16B from the first portion 12a (in FIG. And a second portion 12b extending toward the magnetic grid 17 located on the lower stage. The first portion 12a and the second portion 12b are integrally formed and are electrically and mechanically connected to each other. The fixed contact 12 is fixed to the above-described case, and although not shown, is formed integrally with the power supply side terminal or electrically connected to the power supply side terminal via another conductive member.

Here, the second portion 12b of the stationary contact 12 corresponds to the second arc runner according to the present invention.
The movable contact 14 has a movable contact 13 that comes into contact with the fixed contact 11 at one end side. Although not shown, the movable contact 14 is a movable contact holder made of an insulator whose other end is rotatably supported by the case. It is rotatably connected and is urged toward the stationary contact 12 by a contact spring. 1 to 8 show a state in which the movable contact 14 is open.
The arc dividing means 15 includes an intermediate electrode 18, an arc runner 19, and a second portion 12 b of the stationary contact 12.

  The intermediate electrode 18 is made of a conductive material. The intermediate electrode 18 divides the arc 20 into two arcs 21 and 22 by the movement of the arc 20 generated between the fixed contact 11 of the fixed contact 12 and the movable contact 13 of the movable contact 14 during the opening operation. An arc dividing portion 18a is provided. The arc dividing portion 18 a is located closer to the movable contact 13 than the fixed contact 11 and closer to the fixed contact 11 than the movable contact 13 in the direction connecting the fixed contact 11 and the movable contact 13 after the opening operation. (See FIG. 4 and FIG. 6). Further, the intermediate electrode 18 extends from the arc dividing portion 18a toward the magnetic grid 17 positioned at the final stage (the lowest stage in FIG. 4) of the plurality of magnetic grids 17 of the first arc extinguishing device 16A. 1 branch portion 18b. Further, the intermediate electrode 18 extends from the arc dividing portion 18a toward the magnetic grid 17 positioned at the first stage (the uppermost stage in FIG. 5) of the plurality of magnetic grids 17 of the second arc extinguishing device 16B. Branch portion 18c. The arc dividing portion 18a, the first branch portion 18b, and the second branch portion 18c are integrally formed and are electrically and mechanically connected to each other.

  In the present embodiment, the first branch portion 18b has a tip positioned at the final stage of the first arc-extinguishing device 16A when viewed in plan from the direction along the magnetic grid array direction GL of the first arc-extinguishing device 16A. Is superimposed on the magnetic grid 17 (see FIG. 4). In addition, the second branch portion 18c is positioned outside the magnetic grid 17 positioned at the first stage of the second arc-extinguishing device 16B in the magnetic grid arrangement direction GL of the second arc-extinguishing device 16B. (See FIG. 5).

  The arc runner 19 is made of a conductive material, and the first stage (the uppermost stage in FIG. 4) of the plurality of magnetic grids 17 of the first arc extinguishing device 16A from the distal end side of the movable contact 14 after the opening operation. It extends towards the magnetic grid 17 located. In the present embodiment, when the arc runner 19 is viewed in a plan view from the direction along the magnetic grid array direction GL of the first arc extinguishing device 16A, one end side is overlapped with the arc division portion 18a of the intermediate electrode 18, and the other end side is the first stage. It overlaps with the magnetic grid 17 located in the (uppermost stage) (see FIG. 4 and FIG. 6). The arc runner 19 corresponds to the first arc runner according to the present invention.

  Here, as described above, the arc runner 19 extends from the distal end side of the movable contact 14 after the opening operation toward the magnetic grid 17 located at the first stage of the first arc extinguishing device 16A. On the other hand, as described above, the first branch portion 18b of the intermediate electrode 18 extends from the arc division portion 18a toward the magnetic grid 17 located at the final stage of the first arc extinguishing device 16A. That is, the tip of the arc runner 19 on the first arc extinguishing device 16A side and the tip of the first branching portion 18b of the intermediate electrode 18 on the first arc extinguishing device 16A side are the same as the magnetic properties of the first arc extinguishing device 16A. They are separated from each other in the grid arrangement direction GL (see FIG. 4).

  Further, as described above, the second branch portion 18c of the intermediate electrode 18 extends from the arc division portion 18a toward the magnetic grid 17 located at the first stage of the second arc extinguishing device 16B. On the other hand, as described above, the second portion 12b of the fixed contact 12 is directed from the first portion 12a provided with the fixed contact 11 to the magnetic grid 17 positioned at the final stage of the second arc extinguishing device 16B. It is extended. That is, the tip of the second branch portion 18c of the intermediate electrode 18 on the second arc extinguishing device 16B side and the tip of the second portion 12b of the stationary contact 12 on the second arc extinguishing device 16B side are the second Are separated from each other in the magnetic grid array direction GL of the arc extinguishing device 16B (see FIG. 5).

  In the intermediate electrode 18, the first branch portion 18b includes two arcs 21 and 22 after the arc 20 generated between the fixed contact 11 and the movable contact 13 during the opening operation is divided by the arc division portion 18a. The arc 21 and the arc runner 19 are guided to the first arc extinguishing device 16A. The second branch portion 18c fixes the arc 22 of the two arcs 21 and 22 after the arc 20 generated between the fixed contact 11 and the movable contact 13 during the opening operation is divided by the arc division portion 18a. It is for guide | inducing to the 2nd arc-extinguishing apparatus 16B with the 2nd part 12b (2nd arc runner) of the contactor 12. FIG. That is, the arc dividing means 15 of the present embodiment has an arc dividing function (an arc of the intermediate electrode 18) that divides the arc 20 generated between the fixed contact 11 and the movable contact 13 into two arcs 21 and 22 during the opening operation. The arc dividing function (the second portion 12b of the fixed contact 12 and the first and second portions of the intermediate electrode 18) for guiding the divided arcs 18a and 22 to the two arc extinguishing devices 16A and 16B, respectively. 2nd branch part 18b, 18c and the arc runner 19) are combined.

  The partition wall 24 includes a first partition wall portion 24a (see FIGS. 1, 4, 7, and 8) provided between the first arc-extinguishing device 16A and the second arc-extinguishing device 16B. Yes. In addition, the partition wall 24 is located closer to the arc runner 19 side than the arc dividing portion 18a of the intermediate electrode 18 in the magnetic grid arrangement direction GL of the second arc extinguishing device 16B, and the first The second partition portion 24b (see FIGS. 1, 5, and 7) provided so as to surround the two branch portions 18c and the second arc extinguishing device 16B. In addition, the partition wall 24 is positioned closer to the fixed contact 11 than the arc division portion 18a of the intermediate electrode 18 in the magnetic grid array direction GL of the first arc extinguishing device 16A, and the first partition wall portion 24a to the The first partition portion 18b and the third partition portion 24c (see FIGS. 4 and 8) are provided so as to surround the first arc extinguishing device 16A. The partition wall 24 is made of an insulating material and supported by the above-described case.

Next, the operation of the circuit breaker will be described.
In the circuit breaker of the present embodiment, when a current detection mechanism (not shown) detects an overcurrent, the movable contact opening mechanism works, and the movable contact 14 opens in the opening direction shown in FIGS. To the extreme. Alternatively, the movable contact 14 is similarly opened by an electromagnetic repulsive force that acts on the contact point when a short-circuit current is applied. At that time, the arc 20 generated between the fixed contact 11 and the movable contact 13 is bent by the electromagnetic force in the direction of the arc dividing portion 18a of the intermediate electrode 18, and the central portion thereof moves to the arc dividing portion 18a of the intermediate electrode 18. To do.
The arc 20 moved to the arc dividing portion 18a of the intermediate electrode 18 is divided (divided) into two arcs by the arc dividing portion 18a, that is, the arc 21 and the fixed contact on the movable contact 13 side (above the arc dividing portion 18a). It is divided into an arc 22 on the eleventh side (below the arc dividing portion 18a) (see FIGS. 1, 2 and 6).

Of the two arcs divided by the arc dividing portion 18 a of the intermediate electrode 18, the upper end 21 a of the arc 21 on the movable contact 13 side (end on the movable contact 13 side) 21 a is moved by the electromagnetic force acting on the arc 21. To the arc runner 19, and then travels on the surface of the arc runner 19 toward the first arc extinguishing device 16 </ b> A (see FIG. 4). Similarly, the lower end (end on the intermediate electrode 18 side) 21b of the arc 21 is moved from the arc division portion 18a of the intermediate electrode 18 to the first branch portion 18b by the electromagnetic force acting on the arc 21. Travels toward the first arc-extinguishing device 16A (see FIGS. 4 and 7).
Thereby, the arc 21 on the movable contact 13 side (upper side) is guided to the first arc extinguishing device 16A (see FIGS. 1 and 4). Since the arc 21 that has reached the first arc extinguishing device 16A is divided by each magnetic grid 17 of the first arc extinguishing device 16A, the voltage between the arc runner 19 and the intermediate electrode 18 increases rapidly.

  On the other hand, of the two arcs after being divided by the arc dividing portion 18 a of the intermediate electrode 18, the upper end 22 a of the arc 22 on the fixed contact 11 side (end on the intermediate electrode 18 side) 22 a is caused by electromagnetic force acting on the arc 22. The intermediate electrode 18 moves from the arc dividing portion 18a to the second branch portion 18c, and then travels on the surface of the second branch portion 18c toward the second arc extinguishing device 16B (see FIG. 5). Further, the lower end (fixed contact 11 side) 22b of the arc 22 is similarly moved from the fixed contact 11 of the fixed contact 12 to the second portion 12b of the fixed contact 12 (second arc runner) by electromagnetic force acting on the arc 22. ), And then travels on the surface of the second portion 12b toward the second arc extinguishing device 16B (see FIGS. 5 and 8).

  Thereby, the arc 22 on the fixed contact 11 side (lower side) is guided to the second arc extinguishing device 16B (see FIGS. 2 and 5). Since the arc 22 that has reached the second arc extinguishing device 16B is divided by the magnetic grids 17 of the second arc extinguishing device 16B, the voltage between the intermediate electrode 18 and the stationary contact 12 rapidly increases.

  Here, as described above, the partition wall 24 is located closer to the arc runner 19 side than the arc division portion 18a of the intermediate electrode 18 in the magnetic grid array direction GL of the second arc extinguishing device 16B, and the first partition wall portion 24a. To the second branch portion 15c of the intermediate electrode 18 and the second partition wall portion 24b provided so as to surround the second arc extinguishing device 16B (see FIGS. 5 and 7). Thereby, the conductive gas generated on the arc runner 19 side (above the intermediate electrode 18) with respect to the arc dividing portion 18a of the intermediate electrode 18 during the opening operation moves to the first arc extinguishing device 16A side. Therefore, the arc 21 on the movable contact 13 side (upper side) after being divided by the arc dividing portion 18a of the intermediate electrode 18 has an electrode shape including the arc runner 19 and the first branch portion 18b of the intermediate electrode 18, and the second shape. By the action of the partition wall portion 24b, the first arc extinguishing device 16A is more effectively guided.

  Further, as described above, the partition wall 24 is positioned closer to the fixed contact 11 than the arc division portion 18a of the intermediate electrode 18 in the magnetic grid array direction GL of the first arc extinguishing device 16A, and from the first partition wall portion 24a. It has the 3rd partition part 24c provided so that the 1st branch part 18b of the intermediate electrode 18 and the 1st arc-extinguishing apparatus 16A might be enclosed (refer FIG.4 and FIG.8). As a result, the conductive gas generated on the fixed contact 11 side (below the intermediate electrode 18) from the arc dividing portion 18a of the intermediate electrode 18 during the opening operation moves to the second arc extinguishing device 16B side. Therefore, the arc 22 on the fixed contact 11 side (lower side) after being divided by the arc dividing portion 18 a of the intermediate electrode 18 has an electrode shape including the second branch portion 18 c of the intermediate electrode 18 and the fixed contact 12. By the action with the third partition wall portion 24c, the second arc extinguishing device 16B is more effectively guided.

  In the circuit breaker of the present embodiment configured as described above, when the current flow path at the time of interruption is, for example, to interrupt the current flowing from the movable contact 14 to the fixed contact 12 side, the arc runner 19 and the intermediate electrode 18, in order of the fixed contact 12, the voltage between the fixed contact 12 and the movable contact 14 is the sum of the voltages generated by the first arc extinguishing device 16 </ b> A and the second arc extinguishing device 16 </ b> B.

  In the circuit breaker of the present embodiment, the arc 20 generated between the fixed contact 11 of the fixed contact 12 and the movable contact 13 of the movable contact 14 during the opening operation is once divided into two arcs (21, 22). The two arc extinguishing devices (16A, 16B) arranged in parallel generate voltages. Therefore, in the circuit breaker of the present embodiment, the magnetic grid 17 can be arranged approximately twice as high as the current breaker in the same manner as the conventional circuit breaker. The generated voltage can also be approximately doubled.

  In the circuit breaker of this embodiment, the total number of magnetic grids 17 is 14 (16 sections are divided by the magnetic grid 17). On the other hand, in the conventional circuit breaker 60 shown in FIG. 11, the total number of magnetic grids 56 is 8 (9 sections are divided by the magnetic grid). Therefore, the circuit breaker of the present embodiment has a voltage generated between the fixed contact 12 and the movable contact 14 during the opening operation with the same height of the current breaker 1 as compared with the conventional circuit breaker. As a result, a voltage about 1.8 times as large as that can be obtained. That is, in the circuit breaker according to the present embodiment, an electromotive force that is 1.8 times higher than that of the conventional power supply voltage can be obtained, so that a higher breaking performance (current limiting performance) can be obtained with the same dimensions. it can.

As described above, according to the circuit breaker of the present embodiment, the following effects can be obtained.
(1) The circuit breaker of the present embodiment is configured so that the arc dividing means 15 generates two arcs between the fixed contact 11 of the fixed contact 12 and the movable contact 13 of the movable contact 14 during the opening operation. Two arc extinguishing devices 16A and 16B that divide the arcs 21 and 22 and extinguish the two arcs 21 and 22 individually are provided. Therefore, the circuit breaker according to the present embodiment can increase the number of magnetic grids 17 that can be arranged within a limited height dimension, and can have a fixed height dimension and the fixed contacts 12 and 12 at the time of opening operation. The voltage generated between the movable contacts 14 can be increased. As a result, the circuit breaker of the present embodiment can obtain a higher breaking performance within the limited height dimension of the current breaking portion 1, and thus can be small and obtain a high breaking performance (high current limiting performance). Can do.

(2) In the circuit breaker according to the present embodiment, the arc dividing means 15 includes the intermediate electrode 18. The intermediate electrode 18 includes an arc dividing portion 18a that is divided into two arcs 21 and 22 by the movement of an arc 20 generated between the fixed contact 11 and the movable contact 13 during the opening operation, and an arc dividing portion 18a. A first branch portion 18b extending toward the first arc-extinguishing device 16A, and a second branch portion 18c extending from the arc dividing portion 18a toward the second arc-extinguishing device 16B. Yes.

  The arc dividing means 15 extends from the distal end side of the movable contact 14 after the opening operation toward the first arc extinguishing device 16A, and is connected to the arc runner 19 connected to the same potential as the movable contact 14. The second contact portion 12b (second arc runner) extends from the first portion 12a provided with the fixed contact 11 of the fixed contact 12 toward the second arc extinguishing device 16B. ing.

  The arc splitting means 15 includes a first arc extinguishing device in which the tip of the arc runner 19 on the first arc extinguishing device 16A side and the tip of the first branch portion 18b on the first arc extinguishing device 16A side are 16A are spaced apart from each other in the magnetic grid array direction GL, and the second branching portion 18c on the second arc extinguishing device 16B side end and the second portion 12b of the stationary contact 12 on the second arc extinguishing device 16B side Are separated from each other in the magnetic grid array direction GL of the second arc extinguishing device 16B.

  Therefore, in the circuit breaker of the present embodiment configured as described above, the arc 21 on the movable contact 13 side of the two arcs 21 and 22 after being divided by the arc dividing portion 18a of the intermediate electrode 18 is The runner 19 (first arc runner) and the first branching portion 18b of the intermediate electrode 18 can be easily guided from the arc division portion 18a of the intermediate electrode 18 to the first arc extinguishing device 16A. Of the two arcs 21 and 22 after being divided by the arc dividing portion 18a, the arc 22 on the fixed contact 11 side is connected to the second branch portion 18c of the intermediate electrode 18 and the second portion 12b ( The second arc runner) can be easily guided from the arc dividing portion 18a of the intermediate electrode 18 to the second arc extinguishing device 16B.

(3) The circuit breaker of the present embodiment has an arc dividing function in which the intermediate electrode 18 divides the arc 20 generated between the fixed contact 11 and the movable contact 13 during the opening operation into two arcs 21 and 22 ( An arc division portion 18a) and an arc guiding function (first and second branch portions 18b and 18c) for guiding the divided two arcs 21 and 22 to the two arc extinguishing devices 16A and 16B, respectively. Therefore, the current interrupting unit 1 can be made compact as compared with the case where the arc dividing function and the arc guiding function are configured separately.

(4) In the circuit breaker of the present embodiment, the partition wall 24 is positioned closer to the arc runner 19 side than the arc dividing portion 18a of the intermediate electrode 18 in the magnetic grid array direction GL, and the first partition wall portion 24a to the intermediate electrode 18 Since the second partition wall portion 24b is provided so as to surround the second branch portion 18c and the second arc extinguishing device 16B, the arc is more than the arc division portion 18a of the intermediate electrode 18 during the opening operation. The conductive gas generated on the runner 19 side (above the intermediate electrode 18) moves to the first arc extinguishing device 16A side. Therefore, of the two arcs 21 and 22 after being divided by the arc dividing portion 18 a of the intermediate electrode 18, the arc 21 on the movable contact 13 side (upper side) is used as the arc runner 19 and the first branch portion of the intermediate electrode 18. The action of the electrode shape including 18b and the second partition wall portion 24b can lead to the first arc extinguishing device 16A more effectively.

  Further, in the circuit breaker of the present embodiment, the partition wall 24 is positioned on the fixed contact 11 side with respect to the arc dividing portion 18a of the intermediate electrode 18 in the magnetic grid array direction GL. Since it has the 3rd partition part 24c provided so that the 1st branch part 18b and the 1st arc-extinguishing apparatus 16A may be enclosed, it is fixed contact 11 rather than the arc division | segmentation part 18a of the intermediate electrode 18 at the time of opening operation. The conductive gas generated on the side (below the intermediate electrode 18) moves to the second arc extinguishing device 16B side. Therefore, of the two arcs 21 and 22 after being divided by the arc division portion 18a of the intermediate electrode 18, the arc 22 on the fixed contact 11 side (lower side) is replaced with the second branch portion 18c of the intermediate electrode 18 and the fixed portion. The action of the electrode shape including the second portion 12b (second arc runner) of the contact 12 and the third partition wall portion 24c can lead to the second arc extinguishing device 16B more effectively.

  In the above-described embodiment, the arc 20 generated between the fixed contact 11 of the fixed contact 12 and the movable contact 13 of the movable contact 14 during the opening operation is once divided into two arcs 21 and 22 and divided. A circuit breaker has been described in which the latter two arcs 21 and 22 are individually extinguished by the two arc extinguishing devices 16A and 16B. However, the present invention is not limited to this. For example, an arc generated between the stationary contact of the stationary contact and the movable contact of the movable contact during the opening operation is once divided into three or more arcs. The divided three or more arcs may be individually extinguished by three or more arc extinguishing devices. As a method of dividing the arc into three or more, for example, there is a method of dividing the arc divided into two into multiple stages so as to further divide the arc. Even in this case, by arranging a plurality of arc extinguishing devices in parallel, a circuit breaker having a small size and a high breaking performance (high current-limiting performance) can be obtained as in the above-described embodiment.

In the above-described embodiment, the intermediate electrode 18 having both the arc dividing function and the arc guiding function has been described as an example. However, the present invention is not limited to this, and the arc dividing function and the arc guiding function may be configured by different members. Even in this case, by arranging a plurality of arc extinguishing devices in parallel, a circuit breaker having a small size and a high breaking performance (high current-limiting performance) can be obtained as in the above-described embodiment.
As described above, the circuit breaker according to the present invention has an effect of being small and capable of obtaining a high breaker, and is useful for a circuit breaker such as a circuit breaker for wiring or a circuit breaker.

  DESCRIPTION OF SYMBOLS 1 ... Current interruption part, 11 ... Fixed contact, 12 ... Fixed contact, 12a ... 1st part, 12b ... 2nd part (2nd arc runner), 13 ... Movable contact, 14 ... Movable contact, 15 ... Arc splitting means, 16A ... first arc extinguishing device, 16B ... second arc extinguishing device, 17 ... magnetic grid, 18 ... intermediate electrode, 18a ... arc splitting portion, 18b ... first branching portion, 18c ... first 2 branch portions, 19 ... arc runner (first arc runner), 20, 21, 22 ... arc, 24 ... partition wall, 24a ... first partition wall portion, 24b ... second partition wall portion, 24c ... third Bulkhead part

Claims (4)

A fixed contact provided with a fixed contact;
A movable contact provided with a movable contact capable of contacting the fixed contact;
Arc dividing means for dividing an arc generated between the fixed contact and the movable contact at the time of opening operation into a plurality of arcs;
A plurality of arc-extinguishing devices each having a plurality of magnetic grids arranged at a predetermined interval in one direction and individually extinguishing arcs divided by the arc dividing means; Circuit breaker characterized by.   2. The circuit breaker according to claim 1, wherein the plurality of arc extinguishing devices are arranged in parallel when viewed in plan from a direction along an arrangement direction of the plurality of magnetic grids. The arc dividing means includes
An arc division part that divides into a plurality of arcs by the movement of the arc generated between the fixed contact and the movable contact at the time of the opening operation, a first of the plurality of arc extinguishing devices from the arc division part A first branch portion extending toward one arc-extinguishing device, and a second arc-extinguishing device adjacent to the first arc-extinguishing device among the plurality of arc-extinguishing devices from the arc division portion An intermediate electrode having a second branch portion extending towards;
A first arc runner extending from the distal end side of the movable contact after the opening operation toward the first arc extinguishing device and connected to the same potential as the movable contact;
A second arc runner extending from the portion of the fixed contact provided with the fixed contact toward the second arc extinguishing device,
The tip of the first arc runner on the first arc extinguishing device side and the tip of the first branch portion on the first arc extinguishing device side are the plurality of the first arc extinguishing device. Spaced apart from each other in the magnetic grid array direction,
The second arc extinguishing device side tip of the second branch portion and the second arc extinguishing device side tip of the second arc runner are the plurality of the second arc extinguishing device. The circuit breaker according to claim 1 or 2, wherein the circuit breakers are spaced apart from each other in the arrangement direction of the magnetic grids. And a partition wall separating the first arc extinguishing device and the second arc extinguishing device,
The partition includes a first partition portion provided between the first arc extinguishing device and the second arc extinguishing device, and an arc dividing portion of the intermediate electrode in the arrangement direction of the plurality of magnetic grids. Is also located on the first arc runner side, the second partition part provided so as to surround the second branch part of the intermediate electrode and the second arc extinguishing device from the first partition part, The first branch portion of the intermediate electrode and the first arc extinguishing device are located on the fixed contact side of the arc dividing portion of the intermediate electrode in the arrangement direction of the plurality of magnetic grids. The circuit breaker according to claim 3, further comprising a third partition wall portion provided so as to surround.

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