JPH0515264U - Circuit breaker - Google Patents

Abstract

(57) [Abstract] [Purpose] In a circuit breaker equipped with an arc runner extending below an arc extinguishing device, an object thereof is to prevent or suppress deformation of the arc runner toward an arc extinguishing plate during current interruption. To do. [Structure] Arc-arc 5 and arc-extinguishing plate 4 adjacent thereto
The electrical insulating cover 7 is attached in a range facing 01 with the arc extinguishing plate 401. [Effect] It is possible to prevent or suppress the deterioration of the arc cutting ability due to the deformation of the arc runner, and to prevent the arc runner from being integrally welded to the arc extinguishing plate.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a circuit breaker having an arc runner extending below the arc extinguishing device, and in particular, the arc runner is deformed toward the arc extinguishing plate by mutual electromagnetic force between the arc extinguishing plate adjacent to the arc runner. Preventing or suppressing.

[0002]

[Prior Art]

 5 and 6 show a peripheral part of an arc extinguishing device of a conventional circuit breaker, FIG. 5 is a plan view (moving contacts are not shown), and FIG. 6 is a sectional view taken along line VI-VI of FIG. The movable contact is also indicated by.

In the figure, reference numeral 1 is a base of a circuit breaker case, and 2 is a movable contactor which is connected to an opening / closing mechanism (not shown) and is connected to, for example, a load side. Reference numeral 201 denotes a contact point of the movable contactor 2, and 3 denotes a fixed contactor having a contact point 301, which is connected to, for example, the power supply side.

Reference numeral 4 denotes an arc extinguishing device arranged so as to face the movable contact 2 and the fixed contact 3, and a plurality of substantially U-shaped arc extinguishing plates 401 open to the side of the contacts 2 and 3 are disposed on the side. The part support plates 402 are arranged in a stacking relationship at intervals in the vertical direction.

Reference numeral 5 is an arc runner, one end of which is fixed to the fixed contactor 3 by a suitable means such as a screw 6, and the other end, that is, a free end, guides the arc toward the back of the arc extinguishing device 4. Further, it extends below the arc extinguishing device 4.

Next, the operation will be described. When a large current such as an overcurrent flows in a state where the contacts 2 and 3 are closed and the contacts 201 and 301 are also closed, the movable contactor 2 separates from the fixed contactor 3 via the opening / closing mechanism, and the contact 201 , 301 are separated and an arc is generated. At that time, the arc causes the arc current to be formed through the arc extinguishing plate 401, and the electromagnetic action of the magnetic flux and the arc current causes the arc to pass over the arc runner 5 in the order shown by A, B, and C in FIG. The arc extinguishing plate 401 divides, cools, and extinguishes the arc.

[0007]

[Problems to be solved by the device]

 As described above, in the conventional circuit breaker, the arc runner 5 extends below the arc extinguishing device 4 so that the arc runs toward the back of the arc extinguishing device 4. However, when an arc current flows through the arc runner 5, the mutual electromagnetic force between this current and the magnetic flux created in the arc extinguishing plate 401 by this current causes the arc runners 5 to be adjacent to each other as shown by phantom lines in FIG. Since it deforms toward the arc plate 401 and the distance between the arc plate 401 and the arc plate 401 becomes short, there is a problem in that the arc dividing ability between the arc plate 401 and the arc extinguish plate 401 decreases. When the deformation becomes large, the arc runner 5 hits the arc extinguishing plate 401, the arc runner 5 is welded and integrated with the arc extinguishing plate 401 due to the high heat of the arc gas, and the arc cutting ability during that time is lost and the arc extinguishing device 4 cannot be removed. There was also a problem.

The present invention has been made to solve the above problems of the conventional art, and an object thereof is to provide a circuit breaker that prevents or suppresses the deformation of the arc runner.

[0009]

[Means for Solving the Problems]

 In order to achieve the above object, a circuit breaker according to the present invention includes an arc runner extending below an arc extinguishing device, and an arc runner interposed between the arc runner and an arc extinguishing plate adjacent thereto. The electrical insulating cover is attached so that

[0010]

[Action]

 In the circuit breaker configured as described above, even if the arc runner is deformed toward the arc extinguishing plate, the electrically insulating cover hits the arc extinguishing plate to prevent further deformation, and the arc runner and the arc extinguishing plate are prevented. The thickness of the electrically insulating cover interposed there between is secured.

[0011]

【Example】

 Hereinafter, an embodiment of the present invention will be described with reference to FIGS. 1 is a partially cutaway plan view of a peripheral portion of an arc extinguishing device according to an embodiment of the present invention (the movable contact is not shown), and FIG. 2 is a sectional view taken along line II-II of FIG. 1 (the movable contact). FIG. 3 is an enlarged perspective view of the arc runner in this embodiment, and FIG. 4 is an enlarged perspective view of an electrically insulating cover used in this embodiment. Therefore, the explanation is omitted.

In the figure, 501 is a screw insertion hole for fixing one end 502 of the arc runner 5 to the fixed contactor 3 with a screw 6, and 7 is a free end 503 of the arc runner 5 and an arc extinguishing plate 401 adjacent thereto. In the illustrated embodiment, the two electrically insulating covers 7 are the left and right sides of the free end of the arc runner 5, and are the electrically insulating covers attached in the area facing each other so as to be interposed between the arc extinguishing plate 401 and the arc extinguishing plate 401. Installed on both sides. When these two electrically insulating covers 7 are mounted at the predetermined positions shown in FIGS. 1 and 3, a gap G is left between them, and the arc runner 5 is exposed in the gap G, so that the arc travels. It does not interfere.

The electrically insulating cover 7 can be molded from a heat-resistant synthetic resin that withstands arc heat, and has a recess 701 having a shape corresponding to the shape of the free end 503 of the arc runner 5 inside. The recess 701 is fitted to the free end 503 and attached by, for example, an adhesive.

When the arc runner 5 is deformed toward the arc extinguishing plate 401 at the lowermost end adjacent to the arc extinguishing plate 401 when the current is cut off, the electrically insulating cover 7 is in a range facing the arc extinguishing plate 401 and the arc extinguishing plate 401. Since it is attached so as to intervene with the plate 401, the electrically insulating cover 7 hits the arc extinguishing plate 401 and prevents the arc runner 5 from being further deformed toward the arc extinguishing plate 401.

Therefore, even if the arc runner 5 is deformed, the thickness T of the portion 702 of the electrically insulating cover 7 interposed between the arc runner 5 and the arc extinguishing plate 401 adjacent to and facing the arc runner 5 is formed. The insulation distance of only (FIG. 4) is secured, the arc dividing ability between them is prevented from further lowering, and the arc runner 5 is also prevented from being integrally welded to the arc extinguishing plate 401.

It is most effective that the thickness T of the portion 702 interposed between the arc runner 5 of the electrically insulating cover 7 and the arc extinguishing plate 401 adjacent to and adjacent to the arc runner 5 is indicated by a phantom line in FIG. This is to match the distance W between the arc runner 5 and the arc extinguishing plate 401 during non-deformation. In this way, the above-described deformation of the arc runner 5 does not occur, and the initially set insulation distance is maintained as it is between the arc runner 5 and the arc extinguishing plate 401 that is adjacent to and opposite to the arc runner 5, and the arc dividing capability is maintained. Does not decrease. Further, it is needless to say that the integral welding of the arc runner 5 to the arc extinguishing plate 401 is also prevented.

The electrical insulation cover 7 is not limited to the above-mentioned configuration, and a plate material made of an electrical insulation material is simply fixed to the surface of the arc runner 5 facing the arc extinguishing plate 401 by an appropriate means such as adhesion. Other various shapes can be adopted, and the gap G is not always necessary. Further, the mounting position of the electrically insulating cover 7 does not have to be at the free end of the arc runner 5, and for that purpose, when mounted on the arc runner 5, even a part of it is adjacent to the arc extinguishing plate 401. It may be attached anywhere as long as it has a portion interposed between.

[0018]

[Effect of the device]

 As described above, in the circuit breaker of the present invention, an electrical insulating cover is attached to the arc runner so as to be interposed between the arc runner and the arc extinguishing plate adjacent thereto. With an extremely simple structure, it is possible to prevent or suppress the deformation of the arc runner at the time of current interruption, prevent or suppress the deterioration of the arc dividing ability, and prevent the arc runner from being integrally welded to the arc-extinguishing plate. The effect is obtained.

[Submission date] December 19, 1991

[Procedure Amendment 1]

[Document name to be amended] Statement

[Correction target item name] 0005

[Correction method] Change

[Correction content]

Reference numeral 5 denotes an arc runner, one end of which is fixed to the fixed contactor 3 by a suitable means such as a screw 6, and the other end, that is, a free end, guides the arc toward the back of the arc extinguishing device 4 . Therefore, it extends below the arc extinguishing device 4.

[Procedure Amendment 2]

[Document name to be amended] Statement

[Correction target item name] 0010

[Correction method] Change

[Correction content]

[0010]

[Action]

In the circuit breaker configured as described above, even if the arc runner is deformed toward the arc extinguishing plate, the electrically insulating cover hits the arc extinguishing plate to prevent further deformation, and the arc runner and the arc extinguishing plate are prevented. A distance equal to the thickness of the electrically insulating cover interposed therebetween is secured.

[Brief description of drawings]

FIG. 1 is a partially cutaway plan view of a peripheral portion of an arc extinguishing device according to an embodiment of the present invention, in which a movable contact is not shown.

2 is a cross-sectional view taken along the line II-II in FIG. 1, which also shows a movable contactor.

FIG. 3 is an enlarged perspective view of an arc runner in the embodiment.

FIG. 4 is an enlarged perspective view of an electrically insulating cover used in the above embodiment.

FIG. 5 is a plan view of a peripheral portion of a conventional circuit breaker, in which a movable contact is not shown.

6 is a cross-sectional view taken along line VI-VI of FIG.
The movable contact is also shown.

[Explanation of symbols]

 2 movable contact 3 fixed contact 4 arc extinguishing device 401 arc extinguishing plate 5 arc runner 7 electrical insulation cover

Claims (1)

[Scope of utility model registration request] 1. A fixed contact, a movable contact that opens and closes with respect to the fixed contact, and a plurality of arc-extinguishing plates that are held in a stacking relationship with a gap therebetween, and the fixed contact and the movable contact. An arc-extinguishing device arranged to face each other and extinguishing an arc generated between the two contacts when the current is cut off, and one end fixed to the fixed contact and a free end extending below the arc-extinguishing device. In the circuit breaker equipped with an arc runner, an electric insulating cover is attached to the arc runner in a range facing the arc extinguishing plate adjacent to the arc runner so as to be interposed between the arc extinguishing plate and the arc extinguishing plate. Circuit breaker to do.