JPS58147936A - Arc extinguisher for breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a breaker ring in which a driving yoke having a U-shaped cross section is disposed close to a contact point or an arc travel plate to apply driving force to the arc.

A small breaker generally called a no-fuse breaker (in this case, an arc extinguishing device consisting of a grid block that stacks multiple grids and sucks the arc from the arcing part and extinguishes it in parts), and this arc extinguishing device An arc traveling plate is provided that extends from both the movable and fixed contacts to the arc extinguishing device at the same potential to facilitate arc transfer to the arc. A driving yoke is arranged to surround the contact or the arc running plate, and this driving yoke applies a magnetic driving force to the arc from the arc generating part toward the arc extinguishing device, so that the arc transition occurs more quickly. Sometimes it is.

The driving force of the driving yoke described above increases as the gap between the opposing surfaces of the yoke is reduced (However, conventionally, ordinary iron was used as the material for the yoke, so the smaller the gap, the better the conductor of electricity.) The arc transfers to the driving yoke, short-circuits the arc through the yoke, and the magnetic flux either disappears or becomes extremely small, resulting in a state in which the driving force against the arc decreases or the arc remains stuck in the yoke. This may cause problems with current-limiting interrupting characteristics and insulation recovery performance after interrupting.For this reason, it is necessary to make the gap larger or insulate the yoke (therefore, the gap becomes larger by the thickness of the insulating material). Therefore, in the past, the driving force of the driving yoke had to be considerably sacrificed.

The present invention has been made in view of the above-mentioned problems, and it is an object of the present invention to construct a driving yoke using soft ferrite which has excellent magnetic properties and has an electrical resistance much higher than that of iron. Therefore, it is an object of the present invention to provide a breaker that allows a small amount of current to flow through the yoke even if the gap between the opposing surfaces of the yoke is made small and that good current limiting and breaking characteristics can be obtained.

Hereinafter, the present invention will be explained based on the drawings (illustrated as an embodiment). (Moon is an arc extinguishing device, and a grid (3) having a groove (2) that opens on the arcing part X side is connected to the left and right side plates (4). ) (Therefore, it is made up of grid blocks that are stacked and supported. (5) is a movable contact having a movable contact (6), (7) is a fixed contact. (8) is an insulating material stand. in,
Arc extinguishing device (bottom wall (9) where the moon is placed and left and right side walls (1)
0). (11) is an arc-resistant insulating plate provided to cover the side wall (10), and is made of mica, fiber, etc. (12) is the upper arc running plate, (13) is the lower arc running plate, and the second arc running plate (12) carries the arc on the movable contact (5) side from the lower arc running plate (13). Each arc on the fixed contact (7) side is guided to the arc extinguisher (1).

(14) is a drive yoke, which is made of soft ferrite and has a U-shaped cross section. Vertical part (15
) and two vertical walls (17) for the terminal (16), surrounding the fixed contact (7) and the vertical part (15). (6) and the fixed contact (7) act to apply a magnetic driving force in the direction of the arc extinguishing device (1) and promote the arc extinguishing action. Here, since the driving yoke (14) has extremely high electrical resistance compared to iron, it is assumed that the arc or yoke 1
Even if something happens to the yoke, the current flowing through the yoke is small, and the arc may be short-circuited through the yoke.
The arc does not become stuck to the yoke.

- As mentioned above, the present invention is equipped with a driving yoke made of soft ferrite, which has irregular magnetic properties as a soft magnetic material and has a higher electrical resistance than iron, and the yoke does not cause arc short circuits. There is no need to increase the gap between the opposing surfaces of the yoke or use insulating plates made of ceramic or nylon, which can increase magnetic resistance. It has the advantage that it can be easily generated and good current limiting and breaking characteristics can be easily obtained.

[Brief explanation of drawings]

FIG. 1 is a partially cutaway side view of an embodiment of the breaker of the present invention;
FIG. 2 is an exploded perspective view of the same as above. (1)... Arc extinguishing device, (6)... Movable contact, (7)
... fixed contact, (12), (13) ... arc traveling plate, (14) ... drive yoke, X ... arcing part. Patent applicant Matsushidenjiri Co., Ltd. Representative patent attorney Toshimaru Takemoto (two idiots) Figure 1

Claims (1)

[Claims] (11) In a breaker in which a driving yoke having a U-shaped cross section and opening in the direction of the arc firing part is arranged so as to surround the contact point or the arc traveling plate, and applying a driving force to the arc in the direction of the arc extinguishing device, A breaker arc extinguishing device whose driving yoke is made of soft ferrite.