JPS59121715A - 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, and more particularly to a switch having an arc extinguishing mechanism that turns on and off current and extinguishes an arc generated when the electric current is cut off.

This type of switch is suitable for application to electromagnetic contactors, molded circuit breakers, and the like.

A conventional electromagnetic contactor is constructed as shown in FIG.

That is, in the figure, 10 is a mounting base molded from a synthetic resin material, and 12 is a mounting base molded from a synthetic resin material.
14 is a movable core that faces the fixed core 12 and is similarly laminated with silicon steel plates; 16 is a movable core that holds the movable core 14 at the lower end and has a corner It is a cross piece made of synthetic resin and has a window 18.

Reference numeral 20 denotes a movable contact which is inserted and held in the corner window 18 of the crossbar 16 by being pressed by a screw 22,
A movable contact 24 is disposed on the lower surface of the end extending outside the corner window 18.

Reference numeral 26 denotes an operating coil that attracts the movable core 14 to the fixed core 12 against a tripping force (not shown).

A fixed contact 28 faces the movable contact 20 and is energized with a tongue current on the base 30. A fixed contact 32 is disposed on the upper surface of the base 30, facing the movable contact 24, and the outer A terminal portion 34 is formed in the portion, and a terminal hole 36 for connecting to an external circuit is provided on this terminal portion 34.

38 is an arc generated between the movable contact 24 and the fixed contact 32; 40 and 42 are metal arc extinguishing plates made of a magnetic material for extinguishing the arc 38; metal arc extinguishing plates 40 and 42 are the second
As shown in the figure, they are held on the fixed contact 28 by an arc cage 44 that covers them so as to be spaced apart and parallel to each other.

In FIG. 1, since the electromagnetic contactor has a bilaterally symmetrical configuration, only the right half thereof is shown in cross section.

Next, the operation of the above conventional device will be explained.

First, by energizing the operating coil 26 from the state shown in FIG. The fixed contact 32 is pressed by the pressing force of the pusher screw 22, and the fixed contact 28 and the movable contact 20
A current path through is closed.

Next, when the operating coil 26 is demagnetized from this state, the movable iron core 14 is moved upward by the tripping ring and separated from the fixed iron core 12, and accordingly, the movable iron core 14
also returns to its original position, and the fixed contact 32 and movable contact 24 are separated. At this time, an arc 38 is generated between the fixed contact 32 and the movable contact 24, but this arc 38 is extinguished by the metal arc extinguishing plates 40, 42 at the current zero point, and the current is interrupted.

The arc extinguishing process of the arc 38 will be explained in detail with reference to the vertical sectional view of the arc extinguishing chamber shown in FIG.
The arc 38 generated between the metal arc extinguishing plate 4o and the fixed contact 32 is attracted to the inner metal arc extinguishing plate 4o, and is elongated in an arc shape as shown by the reference numeral 38A. Next, since the fixed contact 28 is formed in a U-shape, the driving of the arc 38 is facilitated by the magnetic field formed by the current flowing through the fixed contact 28, and the arc 38 is further elongated. Then arc 3
8 is stretched, the arc voltage increases, and as a result, dielectric breakdown occurs between the fixed contact 28 and the metal arc-extinguishing plate 4o, and between the metal arc-extinguishing plate 40 and the movable contact 24, and the arc 38A It is divided into arcs 38B and 380.

Next, one arc 380 is further attracted to the outer metal arc-extinguishing plate 42 and is driven and promoted by the magnetic field formed by the current flowing through the fixed bridge tensioner 28.
It is stretched as shown in 8D. When the arc 38D is stretched and the arc voltage increases, it is divided into two arcs 38B and 38F'.

Therefore, arc 38 ends up with three arcs 38B
, 38F, and 38F, and the arc is extinguished at the current zero point to cut off the current.

In the conventional switch, arc extinguishing is performed as described above, but since the distance between the metal arc extinguishing plate 40 and the fixed contact 28 is short, it is necessary to increase the length of the arc 38D between them. Therefore, arcs 38E and 38 of arc 38D
The arc 38 is not easily divided into F, and the arc 38 tends to stick between the tip of the metal arc extinguishing plate 40 and the fixed contact 28, which tends to cause electric field concentration at one end of the arc 38D, and has poor heat conduction. Since it is concentrated at the tip of the inner metal arc-extinguishing plate 40, it has the disadvantage that the interrupting performance is extremely reduced.

The present invention has been made in view of the above-mentioned conventional problems, and its purpose is to overcome the drawbacks of the conventional device by receiving both ends of the arc on a flat surface that is less likely to cause electric field concentration and has good heat conduction. It is an object of the present invention to provide a new switch which can completely improve the breaking performance.

In order to achieve the above object, the present invention provides a fixed contactor in which a fixed contact is arranged in series, and a movable contactor in which a movable contact facing the fixed contact is arranged in series! an It element, a commutation electrode disposed on the back side of the movable contact, and a U-shaped metal arc-extinguishing plate having connecting planes facing the fixed contact, the movable contact, and the commutation electrode, respectively. A notch groove is formed in a plane of the metal arc-extinguishing plate facing the movable contact and the commutation electrode.

Hereinafter, preferred embodiments of the present invention will be described based on the drawings.

FIG. 4 is a perspective view showing an embodiment of the switch according to the present invention.

In the present invention, a commutating electrode 46 on a flat plate is disposed at a required distance on the back side of the movable contact 20, that is, on the opposite side from the fixed contact 28, and the metal arc-extinguishing plate 40 of FIG. 42
Instead, a lower plate 48 facing the upper surface of the fixed contact 28
A U-shaped metal arc-extinguishing plate 54 made of a magnetic material is provided, in which a side plate 50 facing the side surface of the movable contactor 20 and a top plate 52 facing the lower surface of the commutating electrode 46 are connected. A notch groove 56 is formed in this metal arc-extinguishing plate 54 from the top plate 52 to the side plate 50.

The above is an example of the configuration of the present invention. Next, the arc extinguishing process will be explained with reference to a longitudinal sectional view of the arc extinguishing chamber shown in FIG.

The arc 38 generated between the movable contact 24 and the fixed contact 32 is attracted to the side plate 50 of the metal arc-extinguishing plate 54, and is curved and stretched as shown by reference numeral 38A. Then, the arc 38A is driven by the magnetic field formed by the current flowing through the fixed contact 28 formed in a U-shape, and the arc 38A is driven.
8A is further stretched. Since the arc voltage of this stretched arc 38A becomes high, dielectric breakdown occurs between the fixed contact 28 and the lower plate 48 of the metal arc extinguishing plate 54, and between the movable contact 24 and the side plate 50 of the metal arc extinguishing plate 54. occurs and the arc 38A becomes two arcs 38B.

It is divided into 380 parts. One of the divided arcs 380 is driven by the magnetic field formed by the current flowing through the metal arc-extinguishing plate 54, and is extended toward the commutating electrode 46 as shown by reference numeral 38D. When this arc 38D is stretched and the arc voltage increases, dielectric breakdown occurs between the top plate 52 of the metal arc extinguishing plate 54 and the commutating electrode 46, and the arc 38D becomes like an arc 38G, and finally two arc 38
B.38GfJ! - The arc is extinguished at the current zero point and the current is cut off.

In this case, the two arcs 38B and 38G have flat parts (commutating electrode 4
6. Since the current reaches zero point at the metal arc-extinguishing plate 54 and the flat part of the fixed contact 28, the interrupting performance is significantly improved compared to the conventional device.

Further, the driving situation of the arc 380 generated between the metal arc-extinguishing plate 54 and the movable contact 24 will be explained with reference to FIG. 6. Since the notch groove 56 is formed in the metal arc-extinguishing plate 54,
The arced gas generated by the arc 38A in FIG. 5 passes through the cutout groove 56. This arced gas contains ionized ions and electrons, so
The legs of the arc 380 are easily formed in the vicinity of the notch groove 56, the arc time at the time of interruption is shortened, and the arc energy is reduced, so that the interruption performance is improved in this respect as well.

Furthermore, as shown in Figure 6, the arc 3800 feet has a current I
flows in, the arc 380 is subjected to the force F shown in FIG. 6, and the arc 380 heals and travels in the notch groove 56. Therefore, thermal damage to the arc cutter 44 due to arc heat is reduced, so the switching life is shortened. It can extend the lifespan.

In the above embodiment, a case has been described in which the fixed contact 28 is formed in a U-shape, but the same effect as described above can be obtained even if the fixed contact 28 is formed in a U-shape.

Moreover, although the case where the present invention is applied to an electromagnetic pull-out switch has been described above, it goes without saying that the present invention can also be applied to other switches such as a wired circuit breaker.

As described above, according to the present invention, a commutating electrode is disposed on the back side of a movable contact, and a U-shaped metal having connecting planes facing the commutating electrode, the movable contact, and the fixed contact, respectively. An arc-extinguishing plate is provided, and a cutout groove is formed on the plane of the metal arc-extinguishing plate facing the movable contact and the commutating electrode, which significantly improves the interrupting performance and prevents damage to the cover due to arcing. It has excellent effects such as being able to reduce

[Brief explanation of drawings]

Fig. 1 is a half sectional view of a conventional device, Fig. 2 is an enlarged perspective view of its main parts, Fig. 3 is an enlarged sectional view for explaining the operation of the conventional device, and Fig. 4 shows an embodiment of the present invention. The perspective view shown, FIG. 5, and FIG. 6 are a sectional view and a perspective view for explaining the operation. The same members in each figure are given the same reference numerals, 20 is a movable contact, 24 is a movable contact, 28 is a fixed contact, 32 is a fixed contact, 46 is a commutation electrode, 54 is a metal nine arc extinguishing plate, 56 is a notched groove. Agent Patent attorney Makoto Kuzuno - (1 other person) Procedural amendment (voluntary) 1. Display of the incident Tokugansho! '17-2314.5
No. 5 No. 2, Name of the invention Switch 3, Part 5 to the person making the amendment Representative Kata Yuhito, Supplement H pair January 1'1111!
moon (leap)

Claims (1)

[Claims] (1) a fixed contact in which a fixed contact is arranged in series, a movable contact in which a movable contact facing the fixed contact is arranged in series, and a commutation electrode arranged on the back side of the movable contact; A U-shaped metal arc-extinguishing plate having a connecting plane facing the fixed contact, the movable contact, and the commutation electrode, respectively, and the metal arc-extinguishing plate facing the movable contact and the commutation electrode. A switch characterized by having a cutout groove formed in a flat surface.