JPS6286630A - Arc extinguisher - 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 [Field of Industrial Application] The present invention relates to an arc extinguishing device used in a circuit breaker or the like, and particularly to the structure of its exhaust port.

[Conventional technology]

FIG. 4 shows a conventional arc extinguishing device disclosed in, for example, Japanese Unexamined Patent Publication No. 55-117822.

When the movable contact (2) moves away from the fixed contact (4) due to the breaking operation, an arc is generated between both contacts (2) and (4).

This arc moves between the upper arc running plate (6) and the lower arc running plate (8). And grid board Q
It is magnetically attracted by Q and divided. Further, the arc gas generated by the arc is discharged from the hole □ of the exhaust plate (b) to the exhaust port @, and is further discharged from the exit qFJ of the exhaust port (6). In order to show the details of the exhaust plate αυ, the line v-■ in Fig. 4 is used.
An enlarged cross-sectional view of Fig. 5 is shown in Fig. 5.

A plurality of holes α4 are provided, and the exhaust gas is discharged from the holes σ4.

[Problem that the invention seeks to solve]

However, conventional devices have the following problems.

Since the arc running plate (6) is provided with a protrusion (6a), the arc gas mainly flows through the lower arc running plate (3).
) flows along For this reason, most of the arc gas is discharged from the hole at the bottom of the exhaust plate αυ to the exhaust port (b) as shown by the arrow. Then, some of the arc gas discharged to the exhaust sun goes into the upper hole □□□ as shown by arrow (6).
flows backward through the Therefore, the arc gas cannot be discharged smoothly, and the gas pressure in front of the arc increases.
The arc was no longer running smoothly. In addition, since the exhaust plate (b) was bent at an almost right angle from the exhaust port @, the flow of arc gas was even worse, which hindered the movement of the arc. If the arc travels slowly in this way, it takes time for the arc to be divided by the grid plate GO. As a result, as shown in FIG. 6, there was a problem in that the initial rise of the arc voltage was poor and the current-limiting time-interrupting performance was poor.

The object of the present invention is to solve the above-mentioned problems and to obtain an arc extinguishing device having excellent current-limiting and time-interrupting properties.

[Means for Solving the Problems] The arc extinguishing device according to the present invention has exhaust plates installed approximately perpendicularly to the grid at a part of the circumferential edge of the grid, on both sides of which the exhaust plates are installed approximately point-symmetrically to each other. A first group of holes and a second group of holes are provided, and an exhaust port for discharging the arc gas discharged from the first group of holes and the second group of holes is provided in the first group. It is divided into a second exhaust port.

[Effect]

The arc gas flowing along the upper arc running plate is carried through the first group of holes in the exhaust plate and is discharged from the first exhaust port, and the arc gas flowing along the lower arc running plate is discharged through the first group of holes in the exhaust plate. It is discharged from the second exhaust port through the second m-th hole to prevent mutual interference and backflow.

[Embodiments of the invention]

One embodiment of the present invention is shown in FIG. 2 as a first cross section, and an enlarged cross-sectional view taken along the line (■--■) of the first cross line is shown in FIG. The exhaust plate Qυ is installed substantially perpendicularly to the grid a0 so as to be in contact with a part of the peripheral edge of the grid QOO.

A first group of holes (1
8a), and a second group of holes (18b) are provided at the rear and upper position of the other side of the exhaust plate (6), which is substantially symmetrical with this. Note that "backward" refers to the downstream direction of the arc gas flow. Further, a 1° second exhaust port (1
2a) and (12b) are formed and separated by an exhaust plate (b).

In FIG. 1, when the movable contact (2) separates from the fixed contact (4) due to the breaking operation, an arc is generated between both contacts. This arc moves between the arc running plates (6) and (8). In addition, the arc gas flows through the upper arc traveling plate (
Due to the protrusion (6a) of 6), most of the flow flows along the lower arc travel plate (8). This arc gas flows from the first group of holes (Xaa) of the exhaust plate αυ as shown by the arrow (Q).
It is discharged to the first exhaust port (12a). Further, the arc gas flowing along the upper arc traveling plate (6) flows from the second group of holes (18b) of the exhaust plate αυ as shown by the arrow (6).
It is discharged to the second exhaust port (12b). The first exhaust port (
Since the exhaust port 12a) and @2 exhaust port (12b) are separated by the exhaust plate αυ, the arc gas flows do not interfere with each other and flow backwards.

Therefore, the arc gas is quickly discharged and the arc travels quickly. As a result, the time it takes for the arc to be divided by the grid plate αQ is shortened, and the current limiting and interrupting properties are improved as shown in FIG.

〔Effect of the invention〕

As described above, this invention provides the first group of holes for discharging the upper arc gas and the second group of holes for discharging the lower arc gas in the exhaust plate, and separates the upper arc gas from the lower arc gas. , the first one so as not to interfere with each other.
Since the arc gas is discharged from the second exhaust port, the arc gases do not interfere with each other and do not flow, and the arc can be discharged smoothly. Therefore, the time it takes for the arc to be divided by the grid plate is shortened, and the current limiting ability is improved.

[Brief explanation of drawings]

Fig. 1 is a side sectional view showing one embodiment of the present invention, the second factor is an enlarged sectional view taken along the line u-n of the first factor, and the eighth factor is the arc voltage/current characteristic of the present invention. is a side sectional view showing a conventional arc extinguishing device, FIG. 5 is an enlarged sectional view taken along line v-■ in FIG.
12a), (12b) are the first and second exhaust ports, (18
a), (18b) is the first. This is the #2 hole. Note that the same reference numerals in each figure indicate the same or corresponding parts.

Claims (1)

[Claims] (1) A pair of arc running plates that run the arc fired at the contact point, a grid installed between the arc running plates that divides and extinguishes the running arc, and a pair of arc running plates that touch a part of the circumferential edge of the grid. an exhaust plate installed substantially perpendicular to the grid; a first group of holes provided at the lower rear of one side of the exhaust plate; and a second group of holes provided at the upper rear of the other side of the exhaust plate. An arc extinguishing device comprising a group of holes, and first and second exhaust ports formed to face the first and second groups of holes, respectively, and separated by the grid.