JPS59103224A - Switch - 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 switch that switches on and off current, and particularly to an arc extinguishing mechanism thereof.

The main applicable switches of the present invention include electromagnetic contactors and circuit breakers.

First, an example of a conventional electromagnetic contactor will be described with reference to FIG. In Figure 1, (1) is a mounting base made of plastic, (2) is a fixed core laminated with silicon steel plates on this mounting base, and (3) is installed opposite to fixed core (2) and is similar to this. Movable iron core laminated with silicon steel plates (
4) is an operating coil that provides a driving force to attract the movable core (3) and fixed core (2) against a tripping spring (not shown), and (5) is made of plastic and has a square window. The crossbar has a lower end that holds a movable iron core (3). (6) is a movable contact inserted into the corner window of the crossbar (5) and held by a push spring (7);
(6A) is a movable contact provided in the movable contactor (6), (
8) is a fixed contact that is provided opposite to the movable contact (6) and conducts current; (8A) is this fixed contact (
The fixed contact provided at (8), (8 (3) also indicates the terminal portion of this fixed contact (8).

Therefore, (9) is a terminal screw for connecting the electromagnetic contactor main body with an external circuit, (11 is a base for attaching the fixed contact (8), αD is a cover that covers the top surface of the electromagnetic contactor,
Inside it, there is a first metal arc extinguishing plate (13) made of a magnetic material and a second metal arc extinguishing plate for extinguishing the arc 021 generated between the fixed contact (8A) and the movable contact (6A). Fig. 2 shows how these metal arc-extinguishing plates 0, α force, fixed contact (8), and fixed contact (8A) are attached. The plate (131) is configured as a U-shaped frame that covers the fixed contact (8A) and extends over the fixed contact (8), and the second metal arc extinguishing plate (14
) is similarly straddled as a single plate on the outside.

Because of the above configuration, in this conventional electromagnetic contactor, when the operation coil (4) is demagnetized, the movable core (3) is separated from the fixed core (2) by a tripping spring (not shown), and the crossbar (5) is separated from the fixed core (2). ) also age the state shown in Figure 1,
The fixed contact (8A) and the movable contact (6A) are opened and an arc θ is generated between the fixed contact (8A) and the movable contact (6A), but this arc o7J is
1. According to Q4), the arc is extinguished at the spot current zero point, and the current is cut off.

The arc extinguishing process of the arc 021 in this conventional electromagnetic contactor will be explained in more detail as shown in Fig. 3, which shows a cross section of the arc extinguishing chamber.
The arc (12+) generated between the movable contact (6A) and the fixed contact (8A) is attracted by the first magnetic metal arc-extinguishing plate (13) and is stretched like an arc (12A).At this time, The fixed contact (8) has a U-shaped cross section as shown in FIG. is further stretched.In this way, arc Q2
When 1 is stretched out, it is an arc! Since EE becomes high, between the fixed contact (8) and the first metal arc-extinguishing plate (1 to
Dielectric breakdown occurs between the metal arc-extinguishing plate u4 and the movable contact (6A), and the arc (12A) is divided into two arcs (
12g) and (12G). One of the divided arcs (120) is attracted to the second metal arc-extinguishing plate a4, and is driven by the magnetic field created by the current flowing through the fixed contactor (8), and is elongated like an arc (12D). When the tension of this arc (12D) increases, the arc (12D) becomes two arcs (12E
), (12F), and the arc 02 is finally divided into three arcs (12B), (12 phantom, and (12F)), which are extinguished at the current zero point, and the current is cut off.

In the conventional switch, arc extinguishing is performed as described above, but the lower edge position of the first metal arc extinguishing plate U and the second metal arc extinguishing plate AXu facing the fixed contact (8) are set at almost the same horizontal plane position, the suction action of the second metal arc extinguishing plate αa against the arc (12Gt) is not sufficient;
There was a drawback that the arc (120) did not extend as expected, and the arc time was prolonged due to the arc being stuck in this state.

The present invention was made for the purpose of improving the breaking performance of a switch in order to eliminate the above drawbacks.The present invention is characterized by a fixed contact joined to a fixed contact, a a movable contact joined to the movable contact, a first metal arc-extinguishing plate disposed straddling near the tip of the fixed contact in parallel in the contact opening direction to shield these contacts; A second metal arc-extinguishing plate is provided in parallel with the metal arc-extinguishing plate on the side farther from each of the contacts, and the lower edge of the first metal arc-extinguishing plate facing the fixed contact is a movable contact. The opposing distance between the lower edge position of the second metal arc-extinguishing plate and the fixed contact is set to be between the lower edge of the first metal arc-extinguishing plate and the fixed contact. This consists in making it approximately % or less of the separation interval.

Hereinafter, the present invention will be described with reference to the embodiment shown in FIG. 4. The first metal arc-extinguishing plate (13) has an end surface (13A) of the lower edge facing the fixed contact (8) in the open position. The end surface (14A) is set at almost the same planar position as the surface of the movable contact (6A), and is the lower edge position of the second metal arc-extinguishing plate α4.
is a position where the distance is less than % of the distance between the end face (13A) and the fixed contact (8), preferably the distance is 1 to 2%.
- The arrangement is such that the

According to the arc extinguishing mechanism configured in this way, the movable contact (6
An arc (12+
is attracted to the first metal arc-extinguishing plate (13) made of a magnetic material and is stretched like an arc (12A).

Next, the arc (12A) is driven by a magnetic field based on the current flowing through the fixed contact (8) formed in a U-shape as shown in the figure, and the fixed contact (8A) of the arc (12A)
The side foot is moved to the right in the figure on the surface of the fixed contact (8). At this time, as described above, the end face (13A) of the first metal arc-extinguishing plate (13A) almost coincides with the surface of the movable contact (6A) in the open position, and the second metal arc-extinguishing plate 04 ) end face (1
4A) is located at a distance that is less than about % of the separation distance of the end face (13A) from the fixed contact (8), so the lower leg of the arc (12A) moves to the right to form a distraction. The curved arc portion of the arc (12G) comes into contact with the first and second metal arc extinguishing plates (131
It is divided into three parts as shown in B:) and (12F), and a high arc field appears and is cut off at the current zero point.

Therefore, unlike the conventional device, the arc sticking phenomenon such as the above-mentioned arc (12D) generated at the end face of the first metal arc-extinguishing plate α can be prevented, so the above-mentioned configuration greatly improves the breaker operation. It becomes stable and can maintain excellent and high breaking performance.

In the above embodiment, the fixed contact (8) is formed in a U-shape, but it goes without saying that the same effect can be obtained even if it is straight rather than U-shaped. .

In addition, in the above explanation, we will only discuss the case where the present invention is applied to a switch whose contacts are opened and closed by magnets, that is, an electromagnetic contactor. It is obvious that it can also be applied to other switches.

As described above, in the present invention, by maintaining the separated positions of the first and second metal arc-extinguishing plates with respect to the fixed contact in a specific manner, the breaking performance can be significantly improved. There is.

[Brief explanation of the drawing]

Figure 1 is a partial sectional view of a conventional switch, Figure 2 is an enlarged view of the main part showing the arc extinguishing chamber of the switch in Figure 1, Figure 3 is an explanatory diagram of the arc extinguishing operation of the switch in Figure 1, and Figure 4. FIG. 2 is an explanatory diagram showing the arc extinguishing operation of the embodiment of the present invention. (6)...Movable contact (6A)...
・Movable contact (8)...Fixed contact (8A)
...Fixed contact (I7J, (12A) ~ (12
F)... Arc (131... First metal arc-extinguishing plate (13A)... End face α of the first metal arc-extinguishing plate... Second metal arc-extinguishing plate (14A)...The end face of the second metal arc-extinguishing plate,
In the drawings, the same reference numerals indicate the same or corresponding parts. Agent Makoto Kuzuno - Figure 1 Figure 2 Figure 3 Figure 4 312B Procedural amendment (spontaneous) Commissioner of the Japan Patent Office 1, Indication of case Japanese Patent Application No. 57-212281 2
, Title of the invention Switch 3 Person making the amendment Representative Hitoshi Katayama Department of Mitsubishi Electric Corporation 5 Column for detailed explanation of the invention in the specification to be amended. 6. Contents of amendment (1) In the second line of page 3 of the specification, the statement "r (+1) refers to the top surface of the electromagnetic contactor" was changed to "r (11) refers to the top surface of the electromagnetic contactor."
and correct it. (2) The statement "Arc (12) is" on page 4, line 1θ of the specification is corrected to "Arc (12A) is". (3) The statement "arc (12)" on page 4, line 10 of the specification is corrected to "arc (12A)". that's all

Claims (1)

[Claims] A fixed contact joined to the fixed contact, a movable contact opposite the fixed contact and joined to the movable contact, and a movable contact arranged in parallel in the contact opening direction and near the tip of the fixed contact in order to shield these contacts. a first metal arc-extinguishing plate disposed, and a second metal arc-extinguishing plate disposed in parallel with the first metal arc-extinguishing plate on a side farther from each contact of the first metal arc-extinguishing plate, the first metal arc-extinguishing plate The lower edge position of the arc-extinguishing plate facing the fixed contact is located near the open position of the movable contact, and the opposing distance between the lower edge position of the second metal arc-extinguishing plate and the fixed contact is set to A switch characterized in that the distance is approximately % or less of the distance between the lower edge of the metal arc-extinguishing plate and the fixed contact in Item 1.