CN111758142A - switch - Google Patents

Abstract

An object of the present invention is to provide a circuit breaker that can reduce the electric field of the fixed contact even without disposing a shield molded from a resin, and realize a smaller size than that of the prior art. In order to solve the above-mentioned problems, the circuit breaker of the present invention includes a movable contact piece and a fixed contact piece, the fixed contact piece has a bifurcated portion, and on the front end side of the bifurcated portion, when the movable contact piece is disconnected, an arrangement with The movable conductor having a width substantially equal to the gap of the bifurcated portion sandwiches the front end side of the movable contact when the movable contact is turned on.

Description

switch

technical field

The present invention relates to a circuit breaker incorporated in a switchgear such as a switchgear, and more particularly, to a circuit breaker capable of shortening an insulation distance compared with the prior art.

Background technique

A switchgear such as a switchgear is configured by electrically connecting various switches such as a circuit breaker (CB), a circuit breaker (DS), and an earthing switch (ES). Since the built-in circuit breaker in the switchgear switches without load when the circuit breaker is in the open state, the opening/closing speed can be low. By sharing the operator, the circuit breaker and the grounding switch are combined to realize Miniaturization of the entire switchgear.

In particular, although the blade type in which the movable parts of the circuit breaker and the earthing switch are shared is suitable for miniaturization, a large insulation distance is required in order to cope with the high electric field caused by the electric field concentration at the stator end of the circuit breaker. As a result, There is a problem that a switchgear with a built-in circuit breaker increases in size.

In order to solve this problem, in Patent Document 1, "A high-voltage switchgear having a switch including a movable side conductor 2 connected to one busbar conductor; The movable part 4 which is constituted by a conductor member which is pivotally supported by the movable side conductor 2 and is provided for each phase; and insulating gas, and the switch used in the high-voltage switchgear includes a shield 7a, 7b, which is formed by molding the surfaces of the shield electrodes 10c, 10d electrically and mechanically fixed to the movable side conductor 2 using an insulating coating or an insulator, and switches the shields 7a, 7b on the movable side. The opening positions of the parts 4 are arranged so as to face the side surfaces of the movable parts 4, respectively." As described, the electric field is relieved by arranging a shielding member molded from an insulator such as resin at the stator end of the circuit breaker. , shorten the insulation distance, and realize the miniaturization of the switchgear as a whole.

prior art literature

Patent Literature

Patent Document 1: Japanese Patent Laid-Open No. 2012-15009.

SUMMARY OF THE INVENTION

The problem to be solved by the invention

However, the switch of Patent Document 1 requires a molded shield to reduce the electric field, which not only increases the size of the switch itself, but also requires mold manufacturing and injection molding equipment, so there is a large room for improvement in terms of man-hours and costs. .

The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a device capable of reducing the electric field at the end of the stator with a simple structure, thereby contributing to both improvement in manufacturing man-hours and manufacturing cost, and miniaturization. breaker.

technical means to solve the problem

In order to achieve the above object, the circuit breaker of the present invention includes a switch including a movable contact piece and a fixed contact piece, the fixed contact piece having a bifurcated portion, and on the front end side of the bifurcated portion, when the movable contact piece is disconnected At this time, a movable conductor having a width substantially equal to the gap of the bifurcated portion is arranged, and when the movable contact is turned on, the front end side of the movable contact is sandwiched therebetween.

effect of invention

According to the present invention, it is possible to provide a circuit breaker smaller than the prior art by reducing the electric field of the fixed contact and improving the withstand voltage performance.

Description of drawings

FIG. 1 is a perspective view showing a schematic configuration of a circuit breaker according to the first embodiment.

FIG. 2 is a schematic diagram showing an electric field in the vicinity of a bifurcated portion of a fixed contact.

3A is a plan view of a disconnection position used in the circuit breaker of Example 1. FIG.

3B is an A-A sectional view of a disconnection position used in the circuit breaker of Example 1. FIG.

4A is a plan view of the ON position used in the circuit breaker of Example 1. FIG.

4B is an A-A sectional view of the ON position used in the circuit breaker of Embodiment 1. FIG.

5 is a cross-sectional view of a disconnection position used in the circuit breaker of the second embodiment.

6 is a cross-sectional view of a switch-on position used in the circuit breaker of the second embodiment.

Detailed ways

Below, the circuit breaker 100 of this invention is demonstrated based on the Example of illustration. Here, in each drawing, the same reference numerals are used for the same components.

Example 1

The detailed structure of the circuit breaker of Embodiment 1 incorporated in a switchgear such as a switchgear will be described with reference to FIGS. 1 to 4B .

FIG. 1 is a perspective view showing a schematic configuration of a circuit breaker 100 according to the first embodiment. Only the interpole portion of the circuit breaker 100 is shown here, and the known technologies related to the switchgear such as the fixed side of the oscillation circuit and the grounding switch, and the drive system of the insulating rod are omitted from illustration.

The circuit breaker 100 of the present embodiment includes a metal fixed contact 1 and a movable contact 2 of a metal blade structure. By rotating the movable contact 2, the front end of the movable contact 2 is sandwiched and fixed. A blade circuit breaker in the ON position in the gap of the bifurcated portion of the contact 1 . In addition, in the gap of the bifurcated portion of the fixed contact 1, a metal movable conductor 3 having a width substantially equal to the gap is provided so as to be movable up and down.

Here, the electric field in the vicinity of the bifurcated portion of the fixed contact 1 during disconnection will be described using the plan view of FIG.

(a) of FIG. 2 is a diagram showing the outline of the electric field when the movable conductor 3 is not arranged. In this case, as a result of the equipotential lines entering the inside of the bifurcated portion of the fixed contact 1, the equipotential lines are particularly densely spaced at the corners of the front end side of the bifurcated portion, resulting in electric field concentration. As a result, the possibility of discharge from the front end of the fixed contact 1 increases, so it is necessary to increase the insulation distance on the front end side of the fixed contact 1 to avoid discharge. That is, since it is necessary to enlarge the casing of the switchgear, etc., and to secure a sufficient insulation distance around the fixed contact 1, it is difficult to reduce the size of the switchgear as a whole.

On the other hand, (b) of FIG. 2 is a figure which shows the outline of the electric field in the case where the movable conductor 3 is arrange|positioned. As shown, in the case where the movable conductor 3 having the same potential as the fixed contact 1 is provided in the gap of the bifurcated portion of the stationary contact 1, the equipotential line does not enter the bifurcated portion of the stationary contact 1. In the inner side, the electric field at the front end portion can be relaxed, and the possibility of discharge can be suppressed, so that the insulation distance can be shortened compared with (a) in FIG. 2 . That is, since the insulation distance can be shortened, even if the casing of the switchgear is made smaller, discharge can be avoided, and miniaturization of the switchgear as a whole can be easily achieved.

Next, the structure of the circuit breaker 100 of the present embodiment will be described in more detail with reference to FIGS. 3A to 4B .

3A and 3B are a plan view and a cross-sectional view of the circuit breaker 100 in the disconnecting position, respectively.

3A is a plan view of the circuit breaker 100 installed in the casing 4 of the switchgear so as to ensure a predetermined insulation distance, and shows a state in which the movable contactor 2 in the disconnecting position is supported by the support member 9 .

3B is a cross-sectional view taken along line A-A of FIG. 3A , showing the structure in which the movable contactor 2 can rotate about the rotation shaft 8 provided on one end side of the movable contactor 2 as an axis, and the arrangement of the spring 5 and the spring 5 under the movable conductor 3 The structure of the insulator 6. It can be seen from this structure that the movable conductor 3 is urged upward by the spring 5, but since the limiter 7a protruding from the fixed contact 1 limits the upper limit of the movement of the movable conductor 3, when the circuit breaker 100 is open, the fixed contact The height of the upper surface 1 a of the bifurcated portion of the contact 1 is substantially equal to the height of the upper surface of the movable conductor 3 . Further, a guide mechanism 7b for guiding the vertical movement of the movable conductor 3 is also provided on the inner surface of the bifurcated portion of the fixed contact 1, and the position of the front surface 1b of the bifurcated portion of the stationary contact 1 is connected to the position of the movable conductor 3. The position of the front surface is roughly the same.

In this way, when the movable contactor 2 is disconnected and the circuit breaker 100 is at the disconnecting position, the movable conductor 3, which is at the same potential as the fixed contactor 1 by the restrictor 7a or the guide mechanism 7b, is filled with the double contactor 1 of the fixed contactor 1. between the forks. That is, with the structure shown in FIG. 2( b ), the electric field at the corners of the fixed contact 1 can be relaxed and discharge can be suppressed, so that the insulation distance to the case 4 can be shortened.

On the other hand, FIGS. 4A and 4B are a plan view and a cross-sectional view of the circuit breaker 100 in the ON position, respectively.

FIG. 4A is a plan view of the circuit breaker 100 , showing a state in which the front end of the movable contactor 2 is sandwiched between the bifurcated portions of the fixed contactor 1 to be turned on.

4B is a cross-sectional view taken along the line A-A of FIG. 4A , showing that when the movable contact 2 is turned on and is in the on position, the spring 5 is compressed so that the movable conductor 3 sinks downward. In addition, since the insulator 6 is arranged under the spring 5, even when the circuit breaker 100 is energized, no current flows in the spring 5, and heat generation in the spring 5 is not generated. Here, as an example of the spring 5 arranged under the movable conductor 3, a metal spring is exemplified, but any component other than the metal spring 5 may be used as long as it is a stretchable component, such as Resin-made springs, elastomers such as rubber.

According to the present embodiment described above, with the simple structure of disposing the metal movable conductor in the gap of the bifurcated portion of the stationary contact, the bifurcated portion of the stationary contact when the circuit breaker is in the disconnecting position can be alleviated. The electric field at the corners suppresses the discharge, thereby shortening the insulation distance. As a result, the withstand voltage performance of the circuit breaker can be improved, and it is possible to provide a circuit breaker that achieves both improvement in manufacturing man-hours and manufacturing cost, and miniaturization. In addition, by using this circuit breaker, it is possible to reduce the size of the entire switchgear.

Example 2

Next, the circuit breaker 100 of the second embodiment will be described with reference to FIGS. 5 and 6 . In addition, about the same point as Example 1, repeated description is abbreviate|omitted. In addition, in Example 1, it is a structure using the movable contactor 2 which rotates, and in Example 2, it is a structure using the movable contactor 2 which performs linear motion.

5 and 6 are a cross-sectional view of the circuit breaker 100 in an off position and a top view of the circuit breaker 100 in an on position, respectively.

As shown in FIG. 5 , the fixed contact 1 has a bifurcated structure at the front end as in the first embodiment, and the movable conductor 3 is arranged therebetween. In addition, a spring 5 is arranged on the back side of the movable conductor 3 . Also in this embodiment, the movable conductor 3 is biased by the spring 5, but the position of the front surface 1b of the bifurcated portion is substantially equal to the position of the front surface of the movable conductor 3 when disconnected by a stopper or the like.

At this time, since a moderated electric field is formed as described in FIG. 2( b ), the structure of the present embodiment can also achieve the effect of shortening the insulation distance as in the first embodiment.

In addition, as shown in FIG. 6 , when the movable contact 2 moves linearly and is at the ON position, the spring 5 is compressed, and the movable conductor 3 moves to the fixed side, but the height to the movable contact 2 does not occur. Therefore, unlike the structure of FIG. 3B of Embodiment 1, it is not necessary to secure a space above the circuit breaker 100 . That is, in the switchgear using the circuit breaker of the first embodiment, since it is necessary to ensure a sufficient rotation space above the circuit breaker, the switchgear becomes large in the height direction. In the switchgear, since a rotation space above the circuit breaker is not required, the switchgear can be further miniaturized.

Explanation of reference numerals

100...circuit breaker, 1...fixed contact, 1a...upper surface, 1b...front surface, 2...movable contact, 3...movable conductor, 4...case, 5...spring, 6...insulator, 7a... Limiting member, 7b...guide mechanism, 8...rotation shaft, 9...support member.

Claims (8)

1. A switch comprising a movable contact and a fixed contact, characterized in that:

the fixed contact has a bifurcated portion that is,

a movable conductor having a width substantially equal to the gap between the bifurcated portions is disposed on the distal end side of the bifurcated portion when the movable contact is off, and the distal end side of the movable contact is sandwiched between the distal end sides of the bifurcated portions when the movable contact is on.

2. The switch of claim 1, wherein:

when the movable contact is opened,

the movable conductor is at substantially the same potential as the fixed contact, and,

the upper surface of the movable conductor is substantially coincident with the height of the upper surface of the bifurcated portion of the fixed contact,

the front surface of the movable conductor substantially coincides with the position of the front surface of the bifurcated portion of the fixed contact.

3. The switch of claim 2, wherein:

an elastic body for urging the movable conductor toward the upper surface side or the front surface side of the bifurcated portion,

the movable contact moves the movable conductor while compressing the elastic body when the movable contact is connected.

4. The switch of claim 3, wherein:

the movable contact is turned off or turned on by a rotational motion or a linear motion.

5. A switch that breaks an electric circuit by separating a movable contact from a fixed contact, characterized in that:

the front end of the fixed contact piece is a double-fork metal piece,

the movable conductor disposed between the bifurcated metal members is pressed by the movable contact member and moves.

6. The switch of claim 5, wherein:

when the circuit is broken, the movable conductor is used to plug the metal pieces at the front end of the fixed contact,

the surface of the movable conductor is at the same potential as the fixed contact.

7. The switch of claim 6, wherein:

an elastic body is provided on a back side of the movable conductor, and,

an insulator is disposed on a back side of the elastic body.

8. The switch of claim 7, wherein:

a restricting member that restricts a moving range of the movable conductor is provided to the fixed contactor,

the restricting member prevents the movable conductor from protruding from the metal piece at the front end of the fixed contact when the circuit is broken.

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