JPH0630209B2 - Switch - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a switch, and more specifically, at least one pair of contacts is an insulator together with an arc extinguishing plate for cooling an arc. The present invention relates to a switch which is housed in an enclosure and has an arc runner attached to a fixed contact.

[Conventional technology]

1 and 2 show a conventional switch of this type, in which a fixed contact 3 and a movable contact 4 are attached to a fixed electrode 1 and a movable electrode 2, which are arranged opposite to each other, and a pair of contacts is provided. Make up a child. The proximal end of the movable electrode 2 is coupled to the operation mechanism portion 5 and the movable electrode 2 is rotated.
An arc extinguishing plate 6 for cooling an arc generated between the contacts 3 and 4 is arranged near the electrodes 1 and 2. The enclosure 7 is made of an insulating material and houses the operating part of the switch. The enclosure 7 is provided with an arc or hot gas discharge port 8. An arc runner 9 is attached to the fixed electrode 1.

With the above configuration, when the movable contact 4 is now in contact with the fixed contact 3, electric power is supplied from the power source to the load side via the fixed electrode 1 → fixed contact 3 → movable contact 4 → movable electrode 2. It In this state, when a large current such as a short-circuit current flows between the contacts, the operation mechanism section 5 operates to separate the movable contact 4 from the fixed contact 3. At this time, an arc is generated between the fixed contact 3 and the movable contact 4, and an arc voltage appears at the fixed contact 3 and the movable contact 4. This arc voltage is
It rises as the separation distance of the movable contact 4 from the fixed contact 3 increases. At the same time, the arc A is attracted to the arc extinguishing plate 6 side by the magnetic force and extends, so that the arc voltage further increases. Then, the arc A is extinguished at the current zero point of the arc current, and the current is cut off.

Considering the above operation in more detail, the movable electrode 2 is
As shown in FIG. 3, the contacts are rotated to open the contacts. In this opening operation, the spatial distance between the movable electrode 2 and the fixed electrode 1 is determined by the abdomen 2a of the movable electrode 2 and the tip 1a of the fixed electrode 1.
The distance between them is short. On the other hand, the arc generated between the movable contact 4 and the fixed contact 3 receives an electromagnetic force from the current flowing through the fixed electrode 1 and the current flowing through the movable electrode 2, and receives a force in the direction of the resultant force. However, this electromagnetic force is relatively small because the current flows linearly when the electrode structure is closed. Therefore, in general, the arc A moves along with the opening operation of the movable electrode 2 and the movable contact. 4 from the position between the fixed contact 3 and the abdomen 2a of the movable electrode 2 and the tip 1 of the fixed electrode 1.
It moves to a position of a short distance between a and stops there. for that reason. In the figure, the arc A does not come into contact with the arc extinguishing plate 6 located on the right side of the contacts 3 and 4, and the arc A is not cooled, so that there is a problem that the desired breaking performance cannot be obtained.

Further, even if the distance between the abdomen 2a and the tip 1a is not particularly short as described above, there are many structures having a short distance between the fixed contact 3 and the movable contact 4, and in this case, the arc is Stagnation occurs between contacts 3 and 4. Then, even if the arc is cooled by the arc extinguishing plate 6, contact wear is promoted due to the stagnation of the arc on the contact, which causes a serious obstacle to the upgrade of the breaking capacity of the switch.

In order to solve the above problems, the present inventors have proposed a fixed contactor as shown in FIG. That is, the arc runner 19 having a substantially U-shape and having a notch groove 19c formed at the center is fixed to the fixed electrode 11, and the fixed contact 13 attached to the fixed electrode 11 is made to face the notch groove 19c. It will be.

The operation of such a structure will be described with reference to FIGS. FIG. 5 shows the time when the electrodes are closed. The tip 12a of the movable electrode 12 to which the movable contact 14 is attached extends beyond the position of the movable contact 14 to form an arc horn. Notch groove 19c of arc runner 19
Facing. FIG. 6 shows the initial state of the contact opening in the current cutoff operation.
The arc A generated between 4 and 4 is stuck at this position for a while. As the contact opening progresses, a part of the arc runner 19 and the tip portion 12a of the movable electrode 12 are moved beyond the distance between the contacts 13 and 14.
As shown in FIG. 7, when the distance between the contact points 13 and 14 becomes short, the arc A immediately passes from the contact points 13 and 14 to the arc runner 19.
And the tip portion 12a. At this time, the tip 12a
Acts as an arc horn, and the arc A has a large distance from the movable contact 14 due to the transfer, so that the wear of the movable contact 14 is significantly reduced. Further, since the arc A is strongly pressed against the arc extinguishing plate on the right side of the contact to be cooled, the current interruption performance is also improved.

[Outline of Invention]

The present invention is to further improve the above-mentioned constitution, and to aim to minimize the consumption of the contacts by extremely advancing the time of arc transition, and to prevent the contact electrode from being worn at the tip of the movable electrode. The present invention provides a switch in which opposing transition surfaces are formed in a cutout groove of an arc runner.

Example of Invention

8 to 11 show an embodiment of the present invention. In FIGS. 8 to 10, the arc runner 19 attached to the fixed electrode 11 to which the fixed contact 13 is attached has a substantially horizontal U shape. None, a notch groove 19c is formed in the center thereof. Furthermore, the bottom front edge of the notch groove 19c is fixed electrode 11
Is cut and raised to form the arc transition surface 20 on which the arc foot is transitioned. This arc transition surface 20
As shown in FIG. 11, when the electrode is closed, is located at a position facing the tip portion 12b of the movable electrode 12. Other configurations are the same as the conventional ones.

Next, the operation will be described. When the movable electrode 12 rotates and the contact opening operation is started, an arc is generated between the fixed contact 13 and the movable contact 14, and this arc discharges a high-temperature conductive gas to the surrounding space. When this high temperature gas fills between the tip portion 12a of the movable electrode 12 and the arc transition surface 20 provided on the arc runner 19, dielectric breakdown occurs at this portion, and the arc A causes the tip portion 12 to move as shown in FIG.
Dislocation between a and the arc transition surface 20. In such a phenomenon, since the transition area is increased by providing the arc transition surface 20, the dielectric breakdown easily occurs stochastically, and the time at which the arc transition occurs becomes earlier accordingly. Therefore, the time during which the arc is stuck between the contacts 13 and 14 is shortened, and the wear of the contacts is significantly reduced.

13 and 14 show another embodiment, in which the bottom front edge of the cutout groove 19c of the arc runner 19 is fixed to the fixed electrode 11
The arc transition surface 20a is formed by cutting and raising to the opposite side.

Even in such a structure, the tip portion 12a of the movable electrode 12
Since the area of the arc transition surface 20a facing to is large, the early transition of the arc is achieved and the same effect can be obtained.

Note that the contactors are not limited to one pair and may be a plurality of pairs.

(Effect of the Invention) The present invention has a simple structure in which the arc transition surface facing the tip of the movable electrode when the electrode is closed is provided at the bottom of the cutout groove of the arc runner. It is possible to minimize the consumption of the electrode due to.

[Brief description of drawings]

1 to 7 show a conventional switch, FIG. 1 is a partially sectional plan view, FIG. 2 is a sectional view taken along a line II-II in FIG. 1, and FIG. 3 is an operation. FIG. 4 is a partial cross-sectional side view showing a state, FIG. 4 is a partial perspective view, and FIGS. 5 to 7 are main part side views showing an operating state. 8 to 12 show an embodiment of the present invention, FIG. 8 is a partial side view, FIG. 9 is a partial plan view, FIG. 10 is a partial perspective view, and FIG. 11 is a main part. A side view and FIG. 12 are side views of essential parts showing an operating state. 13 and 14 show another embodiment, FIG. 13 is a partial perspective view, and FIG. 14 is a side view of an essential part. 7 ... enclosure, 11 ... fixed electrode, 12 ... movable electrode,
13 ... Fixed contact, 14 ... Movable contact, 19 ... Arc runner, 19c ... Notched groove, 20, 20a ... Arc transition surface. In each figure, the same reference numerals indicate the same or corresponding parts.

Claims (2)

[Claims] 1. A contact comprising a fixed electrode and a rotatable movable electrode, an arc extinguishing plate, an arc runner having a notch groove formed in a central portion attached to the fixed electrode, and the notch. A switch having an arc transfer surface formed at the front edge of the bottom of the groove and facing the tip of the movable electrode when the electrode is closed. 2. A switch according to claim 1, further comprising an arc transfer surface formed by cutting and raising a bottom front edge of the cutout groove.