JPS59108217A - 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 improvement in its arc extinguishing function.

For example, in a switch used as an electromagnetic contactor or a molded circuit breaker, how to improve the breaking performance of the switch is a matter of greatest concern to those skilled in the art.

FIG. 1 shows an example of an electromagnetic contactor as a conventional switch. The contactor shown in the figure has a mounting base 10. A movable contact 20 to which a fixed core 12, a movable core 14, an operating coil 16, a cross spar 18, and a movable contact 20A are joined. presser spring 22,
It is composed of a fixed contact 24 to which a fixed contact 24A is joined, a terminal screw 26, a paste 28, a cover 30, and the like.

The movable contactor 20 is pressed against the lower edge surface of the square window of the cross par 18 by a retaining screw 22, and the cross par 1
8 is connected to a movable iron core 14.

When the operating coil 16 is energized, the movable core 14 is magnetically attracted to the fixed core 12 against a separation spring (not shown), and the movable contact 20A and the fixed contact 24A come into contact with each other. There is.

Here, when the power to the operating coil 16 is cut off, the movable contact 20A and the fixed contact 24A are separated by the action of the separation spring. At this time, an arc 32 occurs between both contacts 20A and 24A, but this arc 32 is caused by the metal arc extinguishing plate 3.
4.36 The arc is extinguished and the current is cut off.

Figure 2 shows the metal arc-extinguishing plate 34, 36 and the fixed contact 24.
The state near A is shown. In addition, Fig. 3 shows both contacts 2OA,
24A shows a process in which the arc 32 generated between 24A and 24A is extinguished.

Here, the arc 32 generated between both contacts 20A and 124A is attracted to the first metal arc-extinguishing plate 34 made of a magnetic material and is elongated as shown by the reference numeral 32A. In this case, if the fixed contact 24 is U-shaped as shown in FIG.
The magnetic field created by the current flowing through the fixed contact 24 drives the arc 32, thereby stretching the shear arc 32 longer. When the arc 32 is stretched, the arc voltage increases, so the fixed contact 24 and the first metal arc extinguishing plate 3
40, dielectric breakdown occurs between the first metal arc extinguishing plate 34 and the movable contact 24A, and the arc 32A is divided into two arcs 32A.
and 32C. One divided arc 32
C is attracted to the second metal arc-extinguishing plate 36 and is driven by the magnetic field created by the current flowing through the fixed contact 24.
It is stretched as shown at 32D. this arc 3
When 2D is stretched and the arc voltage increases, arc 32D is divided into two arcs 32E and 3.2F. The arc 32 is finally divided into 32B, 32F, and 32F, extinguished at the current zero point, and the current is interrupted.

By the way, the arc 32B generated between the movable contact 20A and the first metal arc-extinguishing plate 34 receives the driving force F1 of the magnetic field generated by the current flowing through the first metal arc-extinguishing plate 34, as shown in FIG. The first metal arc-extinguishing plate 34 travels upward.
The arc 32F generated between and the second metal arc extinguishing plate 36 is
The force F2 is received by the magnetic field created by the current flowing through the first metal arc extinguishing plate 34, and the F3 force is applied by the magnetic field created by the current flowing through the arc 32F generated between the second metal arc extinguishing plate 36 and the fixed contact 24. receive the power of Since the forces F2 and F3 are approximately the same in magnitude and opposite in direction, the arc 32E generated between the first metal arc-extinguishing plate 34 and the second metal arc-extinguishing plate 36 is , it is easy to get stuck between the first metal arc-extinguishing plate 34 and the second metal arc-extinguishing plate 36. As a result, the conventional switch had the disadvantage that sufficient breaking performance could not be obtained.

This invention was made in view of the above-mentioned conventional problems, and its purpose is to provide a switch that can reliably prevent the arc from becoming stuck and the breaking performance from decreasing.

In order to achieve the above object, the present invention includes a fixed contact to which a fixed contact is joined, a movable contact to which a movable contact is joined, and a vertical shape from the upper side of the fixed contact to the height of the movable contact joint. a first metal arc-extinguishing plate provided on the
In the switch having a second metal arc-extinguishing plate provided on the opposite side of the movable contact with reference to the metal arc-extinguishing plate, the first metal arc-extinguishing plate is folded back in a U-shape from the lower end thereof. The present invention is characterized in that a folded portion facing the second metal arc-extinguishing plate is provided.

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

FIG. 4 and FIG. 5 show an embodiment of a main part of a switch according to the present invention. The switch, a part of which is shown in the figure, is the same as the conventional switch described above, except for the first metal arc-extinguishing plate 34. The first metal arc-extinguishing plate 34 is provided with a folded portion 34A that is folded back into a U-shape as shown in FIG. Metal arc extinguishing plate 34
It is arranged so as to face the

Here, in FIG. 5, an arc 32 generated between both contacts 2OA and 24A is attracted to a first metal arc-extinguishing plate 34 made of a magnetic material, and is elongated as indicated by the reference numeral 32A.

If the fixed contact 24 is U-shaped as shown in FIG. 3, the arc 32 is driven by the magnetic field created by the current flowing through the fixed contact 24, and the shear arc 32 is thereby further stretched. When the arc 32 is stretched, the arc voltage increases, so the fixed contact 24 and the first metal arc extinguishing plate 3
4, dielectric breakdown occurs between the first metal arc-extinguishing plate 34 and the movable contact 2OA, and as a result, the arc 328 is divided into two arcs 32B and 32C. One of the divided arcs 32C is attracted by the second metal arc-extinguishing plate 36, and is elongated as shown by the reference numeral 32D by being driven by the magnetic field created by the current flowing through the fixed contact 24. .

When this arc 32D is stretched and the arc voltage increases, the arc 32D is divided into two arcs 32g and 32F. Arc 32 ultimately becomes three arcs 32B
, 32F, and 32F, and the arc 32F connects to the T7 creed portion 36B of the second metal arc extinguishing plate 36 and the fixed contact 24.
The arc is extinguished between

By the way, in the case of this invention, since the legs of the arc occur at the folded portion 34A of the first metal arc-extinguishing plate 34, the arc generated between the first metal arc-extinguishing plate 34 and the second metal arc-extinguishing plate 36 32F receives force F2 due to the magnetic field created by the current flowing through the folded portion 34A of the first metal arc-extinguishing plate 34, and along with this, a force is generated between the second metal arc-extinguishing plate 36 and the fixed contact 24. It receives a force F3 due to the magnetic field created by the current flowing through the arc 32F. Since the directions of F2 and F2 are the same, arc 3
2F is driven powerfully, and as a result, the arc is extinguished at the inner parts of the first metal arc-extinguishing plate 34 and the second metal arc-extinguishing plate 36, resulting in excellent interrupting performance. You will be able to get it. Note that the fixed contact 24 does not necessarily have to be U-shaped.

As described above, the switch according to the present invention can reliably improve the breaking performance of the switch with the extremely simple additional configuration of providing a folded portion on the first metal arc-extinguishing plate.

[Brief explanation of drawings]

Fig. 1 is a sectional view showing an example of a conventional switch, Fig. 2 is an enlarged view of the main part of the switch shown in Fig. 1, Fig. 3 is an explanatory diagram of the operation of the switch shown in Fig. FIG. 5 is a perspective view showing the embodiment of the present invention. The same members in each figure are given the same reference numerals, 20 is a movable contact, 20A is a movable contact, 24 is a fixed contact, 24A is a fixed contact, 32. 32A to 32F are arcs, and 34 is a first metal extinguisher. The arc plate 36 is a second metal arc extinguishing plate, and 34A is a folded portion of the first metal arc extinguishing plate. Agent Patent attorney Shin Kuzuno - (1 other person) Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] (1) A fixed contact to which a fixed contact is joined, a movable contact to which a movable contact is joined, and a first metal arc extinguisher provided vertically from the upper side of the fixed contact to the height of the movable contact joint. and a second metal arc-extinguishing plate provided on the opposite side of the movable contact with reference to the first metal arc-extinguishing plate, the lower end of the first metal arc-extinguishing plate A switch comprising a folded part which is folded back into a U-shape and faces the second metal arc-extinguishing plate.