JPS59103220A - 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). Similarly, the movable core is laminated with silicon steel plates, and (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). , (5) is a crossbar made of plastic and having square windows, the lower end of which holds the movable iron core (3). (6) is a movable contact that is inserted into the corner window of the crossbar (5) and is pressed and held by a pressing spring (7); (6A) is a movable contact provided on the movable contact (6); 8) is provided facing the movable contact (6),
A fixed contact that conducts current, (8A) is a fixed contact provided on this fixed contact (8), and (8C) is a terminal portion of this fixed contact (8).

Thus, (9) is a terminal screw for connecting the electromagnetic contactor body to an external circuit, (10) is a base on which the fixed contact (8) is attached, and (11) is a cover that covers the top surface of the electromagnetic contactor.

Since it has the above configuration, when the operation coil (4) is demagnetized in this conventional electromagnetic contactor, the movable core (3) is separated from the fixed core (2) by a tripping spring (not shown).
The crossbar (5) also occupies the state shown in FIG. 1, in which the fixed contact (8A) and the movable contact (8A) are separated and the fixed contact (
An arc (12) is generated between the movable contact (BA) and the movable contact (BA), but this arc (12) is extinguished at the current zero point, and the current is cut off.

By the way, in the conventional electromagnetic contactor, as shown in FIG. 2, the arc (12) is generated by the driving force F2 based on the magnetic field created by the conduction current I of the movable contactor (6) and the fixed contactor (8).
The arc (12) receives a driving force F1 based on the magnetic field created by the conducting current I, but since the magnitudes of Fl and F2 are almost the same and the directions are opposite, the arc (12) connects the movable contact (6A) and the fixed contact (8A). ), he ended up wearing W. In this way, since the arc (12) is not driven, conventional electromagnetic contactors cannot achieve good breaking performance, and the legs of the arc are not transferred to the outside of the contact, resulting in high contact wear. It had drawbacks.

In view of the above points, it is an object of the present invention to provide an arc extinguishing mechanism that promotes arc extinguishing by rapid transition of the arc, thereby reducing contact wear and improving shear breaking performance. Its features include a fixed contact joined to a fixed contact, a movable contact facing the fixed contact and joined to a movable contact, and a U-shaped vertical wall that connects the open part to the fixed contact. a first metal arc-extinguishing plate erected surrounding the fixed contact toward the tip of the child; and a second metal arc-extinguishing plate placed in parallel with the first metal arc-extinguishing plate on a side farther from each of the contacts. The present invention includes an arc-extinguishing plate, and a wavy protrusion is provided on the lower edge of the first metal arc-extinguishing plate facing the fixed contact.

Hereinafter, the present invention will be explained with reference to the embodiments shown in FIG. 3. As is clear from FIG.
An enlarged view is shown in the figure. As shown in the same figure, there is a fixed contact (8A) and a movable contact (8A) inside the arc extinguishing chamber in Figure 3.
) A first metal arc-extinguishing plate (13) and a second metal arc-extinguishing plate (14) made of a magnetic material are provided for extinguishing an arc (12) generated between the two. This first metal arc-extinguishing plate (13) covers the fixed contact (8A) and
It is constructed as a U-shaped frame that straddles the top, and the second
The metal arc-extinguishing plates (14) are similarly arranged side by side as a single plate on the outside, and these first and second metal arc-extinguishing plates (14)
3).

(14) is disposed at a predetermined distance from the fixed contact (8), and as shown in FIG.
The gap (d) that the first metal arc-extinguishing plate (14) occupies with respect to the fixed contact (8) is set smaller than the gap (D) in the first metal arc-extinguishing plate (13). A wavy projection (13B) is provided on the lower edge of 13). Also,
This first metal arc-extinguishing plate (13) is designed to promote the attraction of the arc with three sides surrounding each contact and to shield the surrounding insulators from damage. The U-shaped shape can be selected in consideration of the heat dissipation effect, etc.

Since it has the above configuration, in this electromagnetic contactor, when the operating coil (4) is demagnetized, the movable core (3) is separated from the fixed core (2) by a tripping spring (not shown),
The crossbar (5) also occupies the state shown in FIG. 3, in which the fixed contact (8A) and the movable contact (eA) are separated and the fixed contact (
An arc (12) is generated between the movable contact (6A) and the metal arc extinguishing plate (13),
According to (14), the arc is extinguished at the current zero point, and the current is cut off.

The arc (12) extinguishing process will be explained in more detail with reference to FIG. 5, which shows the cross section of the arc extinguishing chamber. The 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 (1
2) is stretched, the arc voltage increases, so between the fixed contact (8) and the first metal arc-extinguishing plate (13), the first metal arc-extinguishing plate (13) and the movable contact (6A) Dielectric breakdown occurs between them, and the arc (12A) is divided into two arcs (12B) and (12G). One of the divided arcs (12G) is attracted to the second metal arc-extinguishing plate (14), and is driven by the magnetic field created by the current flowing through the fixed contact (8) and stretched like an arc (120). . When the arc voltage increases due to the extension of this arc (120), the arc (120) becomes two arcs (1
The arc (12) is further divided into three arcs (12B), (12E), and (12F).
F), the arc is extinguished at the current zero point, and the current is cut off.

As described above, according to the above-mentioned switch, since the first metal arc-extinguishing plate (13) is configured as a U-shaped frame that stands upright surrounding the movable contact (6A), The generated magnetic field promotes driving and attraction of the arc, and can prevent damage to surrounding insulators as much as possible. Since the first and second metal arc-extinguishing plates (13) and (14) are arranged side by side, the arc is divided as described above, thereby further strengthening the arc-extinguishing ability. Moreover, the wavy protrusion (1
3B), this wavy protrusion ('13
B) The arc suction action draws the arc to the center and extinguishes it, which helps prevent deterioration of the insulating side wall and decrease in arc extinguishing ability due to arc sticking on the side of the arc extinguishing plate. It is possible to make the arc effect even more efficient.

As shown in FIGS. 6 and 7, if the lower edge of the second metal arc-extinguishing plate (14) is bent in the arc driving direction to provide an arc lead portion (14B), As shown in Fig. 7, the arc lead part (14B) is a flat part that makes it difficult to cause electric field concentration on the second metal arc extinguishing plate (14) caused by one end of the arc (12F) and has good thermal conductivity. As a result of arc extinguishing, excellent breaking performance without the risk of burnout is obtained.

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 explanation above, only an example is described where the present invention is applied to a switch whose contacts are opened and closed by a magnet, that is, an electromagnetic contactor, but other switches such as circuit breakers, etc. It is obvious that it can also be applied to

As described above, in the present invention, a U-shaped first metal arc-extinguishing plate and a second metal arc-extinguishing plate installed in parallel thereto are provided, and these are set to face the movable contact. By providing the wavy projections on the lower edge of the metal arc-extinguishing plate 1, there is an effect that the interrupting performance can be significantly improved.

[Brief explanation of drawings]

Fig. ii is a partial sectional view of a conventional switch, Fig. 2 is an explanatory diagram showing its contact configuration, Fig. 3 is a similar partial sectional view of a switch according to an embodiment of the present invention, and Fig. 4 is a similar partial sectional view of a switch according to an embodiment of the present invention. FIG. 5 is an explanatory view of the arc extinguishing operation of the device shown in FIG. 4, and FIG. 6 is a perspective view showing a second metal arc extinguishing plate according to another embodiment of the present invention. FIG. 7 is an explanatory view showing the arc extinguishing operation of the one shown in FIG. 6, FIG. (6)...Movable contact, (6A)...Movable contact, (8)...Fixed contact, (8A)...
Fixed contact, (12), (12A) to (12F)... arc, (13)... first metal arc extinguishing plate, (13B).
... Wave-like protrusion, (14) ... Second metal arc-extinguishing plate. In addition, the same reference numerals in the drawings indicate the same or corresponding parts. Agent Shin Kuzuno - 1st r: tJ. l Figure 2 〒 3 Figure 4 d C'621 7 壬A 8th item δ 9th Figure 3 Commissioner of the Japan Patent Office 1, Indication of the case i, y Application No. 57-212276
- No. 2, name of the invention switch 3, person making the amendment 5, column for detailed description of the invention in the specification to be amended, and drawings. 6. Contents of amendment (1) The statement r (11) on page 2, line 18 of the specification, which says "r (11) refers to the top surface of the electromagnetic contactor..." has been amended to "r (11) refers to the top surface of the electromagnetic contactor..." do. (2) Correct the drawing Medium Temperature 8 as shown in the attached sheet. 7. At least 1 catalog drawing of accompanying documents 11!8 drawings

Claims (1)

[Claims] A fixed contact joined to a fixed contact, a movable contact facing the fixed contact and joined to a movable contact, and a U-shaped vertical wall surrounding the fixed contact with the open part facing the tip of the fixed contact. a first metal arc-extinguishing plate standing upright, and a second metal arc-extinguishing plate installed in parallel with the first metal arc-extinguishing plate on a side farther from each contact point of the first metal arc-extinguishing plate; A switch characterized in that a wavy projection is provided on the lower edge of a metal arc-extinguishing plate facing a fixed contact.