JPH0782797B2 - Switch - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to a switch, and more specifically, a contact composed of a fixed electrode and a movable electrode is formed with a horseshoe-shaped notch to cool an arc. The present invention relates to a switch housed in an enclosure made of an insulating material together with an arc extinguishing plate.

[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.
A horseshoe-shaped notch is formed in the vicinity of the electrodes 1 and 2 and an arc extinguishing plate 6 for cooling the arc generated between the contacts 3 and 4 is arranged. The enclosure 7 is made of an insulating material and houses the opening / closing basic body. The enclosure 7 is provided with an arc or hot gas discharge port 8. Arc runner 9 for fixed electrode 1
Is installed.

With the above configuration, when the movable contact 4 is in contact with the fixed contact 3 now, the electric power is transferred from the power source to the fixed electrode 1 → fixed contact 3 → movable contact 4 → movable electrode 2 in a substantially straight line, and the load Supplied to the side. In this state, when a large current such as a short-circuit current flows between the electrodes 1 and 2, the operation mechanism section 5 operates to separate the movable contact 4 from the fixed contact 3. At this time,
As shown in FIG. 3, an arc A is generated between the fixed contact 3 and the movable contact 4, and an arc voltage appears between the fixed contact 3 and the movable contact 4. This arc voltage 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, in the above opening operation, the spatial distance between the movable electrode 2 and the fixed electrode 1 is the distance between the abdomen 2a of the movable electrode 2 and the tip 1a of the fixed electrode 1. short. On the other hand, the arc A generated between the fixed contact 3 of the movable contact 4 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 as the moving electrode 2 opens. It moves from the position between the contact 4 and the fixed contact 3 to a position of a short distance between the abdomen 2a of the movable electrode 2 and the tip 1a of the fixed electrode 1 and stagnates there. for that reason,
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 current interruption 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. In this case, the arc A Stays between contacts 3 and 4. Thus, although the arc A is cooled by the arc extinguishing plate 6, contact wear due to the stagnation of the arc on the contacts is promoted, which causes a serious hindrance to the upgrade of the switch breaking capacity.

[Outline of Invention]

The present invention is intended to solve the problems of the conventional switch as described above, and an arc having a horseshoe notch formed of a magnetic material having a thickness equal to or greater than the thickness of the fixed contact. By providing a structure in which the suction member is attached to the fixed electrode, there is provided a switch capable of minimizing the consumption of contacts due to an arc.

Further, the present invention, the bottom edge of the horseshoe-shaped notch of the arc-extinguishing plate,
By providing the arc suction member closer to the fixed contact than the bottom edge of the horseshoe-shaped notch, a switch capable of significantly improving the current interruption performance is provided.

Example of Invention

An embodiment of the present invention will be described below with reference to FIGS. FIGS. 4 to 6 show the structure of the fixed contact 11 part having the fixed contact 13 attached to the tip thereof, and the first horseshoe-shaped notch 19a is formed and is thicker than the fixed contact 13 and made of a magnetic material. A rectangular parallelepiped arc attracting member 19 is attached to the fixed electrode 11 with a screw 20.

Next, the operation will be described with reference to FIGS. 7 to 9.
FIG. 7 shows when the movable electrode 12 is closed and the movable contact 14 attached to the movable electrode 12 is in contact with the fixed contact 13.
A part of the protruding portion 12a formed at the tip of the protruding portion 12a protruding toward the fixed electrode 11 faces the horseshoe-shaped notch 19a. Reference numeral 16 designates a plurality of arc-extinguishing plates each having a second horseshoe-shaped notch 16a formed therein.
Located close to 3,14. When the movable electrode 12 rotates to start the contact opening operation, as shown in FIG.
An arc A is generated between the movable contact 14 and the movable contact 14. As shown in FIG. 9, the arc A is attracted by the arc attracting member 19 made of a magnetic material, bends toward the arc extinguishing plate 16, and the legs of the arc move. In this process, rather than the distance between contacts 13 and 14,
The distance between the protrusion 12a of the movable electrode 12 and the arc suction member 19 is configured to be small, and the first horseshoe notch 19 is formed.
The arc A is quickly transferred between the protrusion 12a and the arc suction member 19 by also assisting the arc suction effect of a. The above transition of the arc A is caused by the arc suction member 19 first.
Although it cannot be determined to which part of the arc, the arc A will be attracted to the bottom of the horseshoe-shaped notch 19a of the arc suction member 19 once the arc transfer begins, and the arc extinguishing plate 1
The arc is pressed near the center of 6 and the extinguishing action is achieved. In this way, the arc A is rapidly transferred from between the contacts to the arc suction member 19 side, so that the wear of the contacts is significantly reduced.

Even if the protrusion 12a is not necessarily formed at the tip of the movable electrode 12, a part of the tip of the movable electrode 12 may face the first horseshoe-shaped notch 19a when the electrode is closed.

10 to 12 show another embodiment, the arc suction member 19
The fixed contact 13 is located in the first horseshoe-shaped notch 19a. Other configurations are the same as those in the previous embodiment.

With such a configuration, the arc generated between the contacts is immediately subjected to the magnetic-grade attractive force of the arc attracting member 19, and the bending and transition of the arc are remarkably improved. Further, since the distance between the side surface of the movable electrode and the leg portion 19b of the arc attracting member 19 becomes small, the transfer of the arc between them becomes easy, and the contact wear is further reduced.

13 to 15 show still another embodiment, in which the bottom edge of the second horseshoe-shaped notch 16a of the arc extinguishing plate 16 is more than the bottom edge 19c of the first horseshoe-shaped notch 19a of the arc suction member 19. 16b has fixed contact 13
Are arranged so that they are close to each other. Other configurations are the same as those of the above-described embodiment.

With the above configuration, as described above, the arc transferred to the bottom edge 19c of the first horseshoe-shaped notch 19a must necessarily form a series arc in the plurality of arc extinguishing plates 16, and in the end, the arc extinguishing Board 16
It becomes an arc divided by. The arc thus divided is subjected to strong cooling by the arc extinguishing plate 16 at its current zero point, so that excellent current interruption performance is achieved.

The relative positional relationship between the leg 19b of the arc suction member 19 and the leg 16c of the arc extinguishing plate 16 need not be specified. The reason is that, regardless of which part of the arc foot is in the initial stage of arc transfer, the arc foot always moves to the bottom edge 19c of the first horseshoe-shaped cutout 19a in the latter half of the arc transfer. Is.

The same applies when the contacts are a plurality of sets of switches.

〔The invention's effect〕

As described above, according to the present invention, the arc attracting member, which is made of a magnetic material thicker than the fixed contact and has the first horseshoe-shaped notch formed therein, is attached to the fixed electrode, thereby minimizing the consumption of the contact due to the arc. be able to.

Further, according to the present invention, the bottom edge of the second horseshoe-shaped notch formed on the arc-extinguishing plate is located closer to the fixed contact than the bottom edge of the first horseshoe-shaped notch, so that the current interruption is achieved. The performance can be significantly improved.

[Brief description of drawings]

1 to 3 show a conventional switch, FIG. 1 is a partial sectional plan view, FIG. 2 is a sectional view taken along a line II-II in FIG. 1, and FIG. It is a partial cross-sectional side view which shows a state. 4 to 9 show an embodiment of the present invention. FIG. 4 is a partial perspective view, FIG. 5 is a partial side view, FIG. 6 is a partial plan view, and FIGS. Each of the drawings is a side view of the main part showing the operating state. 10 to 12 show another embodiment, FIG. 10 is a partial plan view, FIG. 11 is a sectional view in a plane along the line XI-XI of FIG. 10,
FIG. 12 is a partial perspective view. FIGS. 13 to 15 show still another embodiment. FIG. 13 is a partially cutaway perspective view of a main part, FIG. 14 is a plan view of the main part, and FIG.
FIG. 15 is a sectional view taken along a line XV-XV in FIG. 7 ... Enclosure, 11 ... Fixed electrode, 12 ... Movable electrode, 12a
...... Projection, 13 ...... Fixed contact, 14 ...... Movable contact, 16 ......
Arc-extinguishing plate, 16a ... second horseshoe notch, 16b ... bottom edge, 19
...... Arc suction member, 19a ...... First horseshoe notch, 19c
…… Bottom edge. In each figure, the same reference numerals indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Shirou Murata 1-8 Midoricho, Fukuyama-shi, Hiroshima Mitsubishi Electric Corporation Fukuyama Plant (56) References JP-A-58-26434 (JP, A)

Claims (6)

[Claims] 1. A fixed electrode having a fixed contact attached thereto, a movable electrode having a movable contact attached thereto and rotatable, and a fixed electrode having a thickness larger than a thickness of the fixed contact attached to the fixed electrode. Opening and closing comprising an arc attracting member made of a magnetic material having a horseshoe-shaped notch and a arc-extinguishing plate having a second horseshoe-shaped notch disposed near the movable electrode and the fixed electrode. vessel. 2. The switch according to claim 1, further comprising a movable electrode having a protrusion forming an arc transition portion at a tip thereof. 3. The switch according to claim 1, further comprising a fixed contact located in the first horseshoe-shaped cutout. 4. A fixed electrode to which a fixed contact is attached, a movable electrode to which a movable contact is attached and is rotatable, and a thickness which is attached to the fixed electrode and is larger than the thickness of the fixed contact. 1. An arc attracting member made of a magnetic material in which a horseshoe-shaped notch is formed, a second horseshoe-shaped notch is formed, and a bottom edge of the second horseshoe-shaped notch is formed near the movable electrode and the fixed electrode. A switch comprising a plurality of arc extinguishing plates arranged closer to the fixed contact than the bottom edge of the horseshoe-shaped notch. 5. The switch according to claim 4, further comprising a movable electrode having a protrusion forming an arc transition portion at a tip thereof. 6. A switch according to claim 4, including a fixed contact located within the first horseshoe-shaped cutout.