JPH09147725A - Circuit breaker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an arc-extinguishing device and a circuit breaker having high performance at a low cost. SOLUTION: This arc-extinguishing device 4 is constituted of arc-extinguishing plates 21 and a molding 25. The arc-extinguishing device 4 is integrally formed for individual poles, not separately for each pole. The arc-extinguishing plates 21 are inserted and buried into the molding 25 when it is molded. The molding 25 is provided with contact point bases and current transformers. The molding 25 concurrently serves as the case of a circuit breaker.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a high performance, low cost circuit breaker.

[0002]

2. Description of the Related Art A conventional circuit breaker is shown in FIGS.
Explanation will be made using 0. 8 is a schematic diagram showing the internal structure of a conventional circuit breaker. FIG. 9 is a front partial perspective view. FIG. 10 is a perspective view and an exploded perspective view of the arc extinguishing device.

The circuit breaker includes a fixed contact 7 and a movable contact 30.
The main circuit is opened and closed by contacting / separating with and. As its name implies, the fixed contact 7 is fixed to the power source side terminal block 5 by brazing or the like. Therefore, the contact / separation is performed solely by the movement of the movable contact 30. The movement of the movable contact 30 is performed by the mechanism unit 6 that operates according to the operation of the handle 3.

An arc is generated when the contacts 7, 30 are separated from each other. Therefore, the circuit breaker is provided with the arc extinguishing device 4 for suppressing the adverse effect of this arc in the vicinity of the contacts 7 and 30. The structure of the most general deionized grid arc extinguishing device is shown in FIG. The deer ion grid type arc extinguishing device is composed of an arc extinguishing plate 21 and a side plate 22.

The arc extinguishing plate 21 is for guiding the generated arc and is made of a magnetic material.
The arc-extinguishing plate 21 is substantially U-shaped, and a plurality of arc-extinguishing plates 21 are prepared for one electrode. These are installed in parallel with each other at a predetermined interval. The side plates 22 are the arc extinguishing plates 2
1 is supported from both ends, and is made of an insulating material. The arc-extinguishing plate 21 and the side plate 22 are connected to each other by the side plate 2
This is done by inserting the protrusions provided on the left and right sides of the arc extinguishing plate 21 into the holes provided at various places of 2 and caulking them. The arc extinguishing device weakens the momentum of the arc gas by passing the generated arc gas through the gap between the arc extinguishing plates 21. In a multi-pole type circuit breaker, one arc extinguishing device 4 is provided for each pole (the arc extinguishing device for three poles is shown on the upper side of FIG. 10).

The outer shell of the circuit breaker is composed of two parts, a molded case 1 and a cover 2. The joint surface of the both is parallel to the circuit breaker mounting surface. This is to improve the accommodating and assembling of the above-mentioned components.

The molded case 1 constitutes the outer surface of the back side of the circuit breaker and also serves as a mount for mounting the respective parts. When this circuit breaker is attached to a wall surface or the like, the outer surface (the left side surface in FIG. 8) of the molded case 1 is installed so as to face the wall surface or the like. The cover 2 constitutes a front outer shell of the circuit breaker 2. The cover 2 is configured to be removable for adjusting the circuit breaker or the like.

The arc extinguishing device 4 described above is housed in the molded case 1. In this case, in order to efficiently capture the generated arc, the U-shaped recess of the arc extinguishing plate 21 surrounds the contacts 7, 30. The pressure becomes very high when arc gas is generated. However, the arc extinguishing device itself is not strong enough to withstand this. Generally, this is dealt with by increasing the thickness of the portion of the molded case 1 that houses the arc extinguishing device (arc extinguishing chamber portion).

The power source side terminal block 5 is provided for each pole of the main circuit.
It is fixed to the mold case 1 with screws or the like. The mechanical section 6 is fixed to the mold case 1. Current transformer (CT) 9 for current detection and zero-phase current transformer (Z) for leakage detection
The CT) 10 is fixed to the mold case 1 directly (or via a mold-made fixing component) together with the conductors forming the main circuit. Among the conductors forming the main circuit, the through conductor 11 includes a current transformer (CT) 9 and a zero-phase current transformer (ZC).
T) and 10 are penetrated. In addition to the above, a load side terminal block, a trip relay 17 for detecting a short circuit, and the like are attached to the molded case 1.

[0010]

The inventor of the present application has studied various aspects of the conventional circuit breaker in order to improve performance and reduce cost. As a result, they have realized that there is a possibility of improving performance by improving the following points 1 to 4, for example.

1. Structure of arc extinguishing device (reducing the number of parts, improving assembly) 1. Contact block fixing method 3. 3. Method for fixing current transformer and zero-phase current transformer Electrical Insulation of Main Circuit Conductor Penetrating Current Transformer and Zero-Phase Current Transformer The present invention aims to provide a higher performance circuit breaker.

It is an object of the present invention to provide a lower cost circuit breaker.

[0013]

In the present invention, the above object is achieved by taking various measures (1 to 7) as described below. However, it is not necessary to adopt all of the following measures at the same time.

1. The arc extinguishing device for each pole is integrated.

2. The arc extinguishing device integrated as described above is constituted by an integrally molded product.

3. As the molding material of the integrated arc-quenching apparatus, a material having a higher strength than the material of the mold case for housing the arc-quenching apparatus is used.

4. The integrated molding arc extinguishing device constitutes a part of the outside of the main body.

5. An overcurrent relay portion, a tripping mechanism portion, conductors constituting a main circuit, and the like are housed in a part of the mold portion of the above-described integrated molding arc extinguishing device to have a function of a mold case.

6. A contact base to which fixed-side contacts are connected and an arc extinguishing device are integrally molded with a molding material.

[7] FIG. An arc-extinguishing device, a contact block that constitutes a main circuit, a current transformer (CT), a zero-phase current transformer (ZCT), and the like are integrally molded with a molding material.

The configuration of the present invention will be described in more detail below.

As a first aspect of the present invention, one or two or more poles each provided with a pair of contacts configured to be in contact with / separable from each other, and an opening / closing mechanism for contacting / separating the contacts are provided. An arc extinguishing device provided for each of the one or more poles for extinguishing the arc gas generated by the contact / separation, and the arc extinguishing device of each pole is integrated with each other. A circuit breaker is provided. By thus integrating the arc extinguishing device for each pole, it is possible to reduce the number of parts of the arc extinguishing device and the number of assembling steps.

It is preferable that the arc extinguishing device has a plurality of arc extinguishing plates, and a supporting member that supports the arc extinguishing plates and that is wholly integrally molded. By constructing the arc extinguishing device as an integrally molded product in this way, the strength of the arc extinguishing device can be increased, and the processing required for fixing the parts constituting the arc extinguishing device becomes unnecessary. Furthermore, by sufficiently increasing the strength of the arc extinguishing device itself, it is possible to reduce the thickness of the case (the mold case 1 in the embodiment described later) that accommodates the entire circuit breaker and use a thermoplastic resin or the like. It is possible to reduce the cost and the weight of the circuit breaker.

It is preferable that a contact stand is provided with one of the two contacts forming the pair of contacts, and the contact stand is integrated with the arc extinguishing device. With this configuration, screws for fixing the contact base can be omitted, and the number of parts and the number of assembling steps can be reduced.

A current transformer (CT) for detecting a current flowing through each of the poles and a zero-phase current transformer (ZCT) for detecting a leakage current are provided, and the current transformer (CT) and the zero-phase current transformer ( ZCT) is preferably integrated with the arc extinguishing device. This makes it easy to fix CT and ZCT. Moreover, the electrical insulation performance of the contact block and CT, ZCT which comprise a main circuit can be improved.

It is preferable that the supporting member constitutes a part of an outer shell of the circuit breaker. By doing so, it is possible to improve the strength of the arc extinguishing device and reduce the number of parts and the number of assembling steps. If an opening / closing mechanism or the like is attached to this support member, the number of parts and the number of assembly steps can be further reduced.

[0027]

Embodiments of the present invention will be described with reference to the drawings.

The present invention mainly relates to an arc extinguishing device among circuit breakers. Therefore, first, the outline of the circuit breaker as a premise will be described, and the arc-extinguishing device according to the present invention (first to fifth embodiments) will be described in detail later.

The circuit breaker of the present invention opens / closes the main circuit by contacting / separating the fixed contact 7 and the movable contact 30. This contact / separation is performed by moving the movable contact 30 by the mechanism unit 6 in accordance with the operation of the handle 3. Various components constituting this circuit breaker, for example, the power supply side terminal block 5, the mechanism section 6, the movable contact block 8, the current transformer for current detection (C
T) 9, the zero-phase current transformer (ZCT) 10 for detecting electric leakage, and the through conductor 11 are directly (or via a fixed component made of mold) fixed to the mold case 1. The through conductor 11 also serves as a load side terminal block. Arc extinguishing device 4
Are housed in the mold case 1 in the vicinity of the movable contact 30. Each of these parts is covered by a cover 2.

In the fifth embodiment described later, the mold case 1 and a part of the arc extinguishing device (mold molding material described later) are integrated.

Hereinafter, the arc extinguishing device according to the present invention (first to fifth)
Embodiment) will be described.

The arc extinguishing device and the circuit breaker of the first embodiment will be described with reference to FIGS. 1 and 2.

As shown in FIG. 1, the arc extinguishing device of the present embodiment comprises an arc extinguishing plate 21, side plates 23, and a top plate 24.

The arc extinguishing plate 21 is for guiding the generated arc and is made of a magnetic material.
The arc-extinguishing plate 21 is substantially U-shaped, and a plurality of arc-extinguishing plates 21 are prepared for one electrode. These are installed in parallel with each other at a predetermined interval. The side plate 23 is the arc extinguishing plate 2
1 is supported from both ends, and is made of an insulating material.

The arc-extinguishing plate 21 and the side plate 23 are connected to each other by the side plate 2
This is done by inserting the protrusions 210 provided on the left and right sides of the arc-extinguishing plate 21 into the holes 232 provided at various places on both sides of the No. 3 plate. Further, grooves 230 are provided on the upper and lower end surfaces of the side plate 23. Further, on one surface side of the top plate 24, rails 240 are provided at intervals according to the left and right widths of the arc extinguishing plate 21 and as many as the number of electrodes of this circuit breaker. By sliding the rail 240 so as to fit it in the groove 230, the top plate 24 and the side plate 23 are coupled to fix the arc-extinguishing plate 21.

The "support member" referred to in the claims corresponds to the molding material 25. The “opening / closing mechanism” corresponds to the trip / mechanism unit 6, the handle 3, and the like.

In the arc extinguishing device of the present embodiment and the circuit breaker using the same described above (see FIG. 2), the arc extinguishing plate 2 is integrated by integrating the arc extinguishing device of each pole of the circuit breaker.
Work such as caulking for fixing 1 to the side plate is unnecessary. Moreover, since the side plate 23 also serves as an inter-wall wall of each pole, the number of parts can be reduced. Further, since the whole is integrated, it can be easily incorporated into the circuit breaker and the number of steps can be reduced.

Further, by adopting such a structure (integration of the arc extinguishing device of each pole, installation of the top plate 24, etc.), the strength of the arc extinguishing device is improved, and the arc extinguishing device itself is provided with Be able to withstand increased pressure. The strength of the arc extinguishing device is further increased by using a material having a high strength (at least a material having a higher strength than the material of the mold case 1) as the material of the molding material 25. Therefore, it is not necessary to increase the thickness of the molded case 1 and the circuit breaker can be downsized accordingly. Generally, the breaking capacity of a circuit breaker is often determined by the strength of the arc extinguishing chamber. Therefore, if the circuit breakers of the same size,
Breaking capacity increases. In addition, high strength materials are generally expensive. Therefore, it is not necessary to use such a material having high strength for the entire mold case 1, which is advantageous in terms of cost.

The second embodiment will be described with reference to FIG.

The arc-extinguishing device of this embodiment includes an arc-extinguishing plate 21,
And a molding material 25. The molding material 25 is manufactured by integrally molding the portions corresponding to the top plate 24 and the side plates 23 in the first embodiment with a molding material. The arc-extinguishing plate 21 is fixed to the molding material 25 by insert molding during this molding. The shape of the arc-extinguishing plate 21 is the same as that of the first embodiment.

Since the arc extinguishing device of the present embodiment described above is manufactured by molding, there is no joint between the portion corresponding to the top plate 24 and the portion corresponding to the side plate 23 in the first embodiment. High strength. Further, since the whole is integrated, it can be easily incorporated into the circuit breaker and the number of steps can be reduced.

A third embodiment of the present invention will be described with reference to FIG.

The arc extinguishing device of this embodiment comprises an arc extinguishing plate 21, a molding material 25, a fixed contact base 26 and a fixed contact 27.

The molding material 25 is manufactured by integrally molding the portions corresponding to the top plate 24 and the side plates 23 in the first embodiment with a molding material. The arc extinguishing plate 21 and the fixed contact base 26 are fixed to the molding material 25 by insert molding during this molding. The shape of the arc-extinguishing plate 21 is the same as that of the first embodiment.

The fixed contact 27 is bonded to the fixed contact base 26 in advance by brazing, crimping or the like.

In the arc-extinguishing device of the present embodiment and the circuit breaker using the same described above, the same effects as those of the second embodiment can be obtained.

Further, in the circuit breaker of the third embodiment, it is not necessary to incorporate the fixed contact base 26 into the case for each phase. The fixed contact base 26 and the arc extinguishing device can be incorporated into the molded case 1 as one component. Therefore, the number of steps for assembling the circuit breaker can be reduced.

A fourth embodiment of the present invention will be described with reference to FIGS.

In addition to the structure of the third embodiment, the fourth embodiment has a current transformer (CT) 28 for detecting a current.
Also, a zero-phase current transformer (ZCT) 29 for detecting the leakage current of the main circuit is integrated.

The current transformer (CT) 28 has a ring shape,
One is provided for each phase. The fixed contact block 26 for each phase is passed through the central hole of the current transformer (CT) 28.

The zero-phase current transformer (ZCT) 29 has a ring shape, and all phases (in the example of FIG.
The fixed contact base 26 of (phase) is penetrated.

The fixed contact base 26, the current transformer (CT) 28 and the zero-phase current transformer (ZCT) 29, together with the arc extinguishing plate 21,
Fixed to the molding material 25 by integral molding
Will be retained.

The "pair of contacts" in the claims corresponds to a set of the fixed contact 27 and the movable contact 30 corresponding thereto. The “contact base” corresponds to the fixed contact base 26.

In the arc-extinguishing device of the present embodiment and the circuit breaker using the same described above, the same effects as those of the above-described third embodiment can be obtained.

Further, in the arc extinguishing device and the circuit breaker using the same of the present embodiment, not only the arc extinguishing device but also
The current transformer (CT) 28 and the zero-phase current transformer (ZCT) 29 are also integrated. Therefore, these can be collectively handled as one component, and the number of assembling steps in assembling the circuit breaker can be further reduced. Also, the assembling work is easier.

Further, the strength of the arc extinguishing chamber is improved and the current transformer (C
T), fixing of the zero-phase current transformer (ZCT) and electrical insulation from the main circuit are easy.

A fifth embodiment of the present invention will be described with reference to FIG.

The present embodiment is an example in which at least a part of the molding material 25 is exposed to the outside, that is, an example in which the molding material 25 constitutes a part of the outer shell of the circuit breaker.

Similar to the fourth embodiment, the molding material 25 serves as a base for accommodating and holding the mechanism portion 6, the relay portion 17, and the through conductor 11. The fourth embodiment is that the fixed contact base 26, the current transformer (CT) 28, the zero-phase current transformer (ZCT) 29, and the arc extinguishing plate 21 are fixed and held by a molding material 25. Is the same as.

According to this embodiment described above, the same effects as those of the other embodiments can be obtained. Further, the number of parts of the circuit breaker and the number of assembling steps can be further reduced. In addition,
In this embodiment, it can be considered that the molding material 25 of the fourth embodiment is integrated with the molding case 1.

[0061]

As described above, according to the present invention, the following effects can be obtained.

1. Reduction of the number of arc-extinguishing device and circuit breaker parts, assembly man-hours, and cost.

2. Improved strength, smaller size and lighter weight of arc extinguishing device and circuit breaker.

3. Current transformer (CT) and zero-phase current transformer (ZC
T) Simplifies the electrical insulation method between main circuit conductors that penetrates and improves reliability.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of an arc extinguishing device according to a first embodiment of the present invention.

FIG. 2 is an exploded perspective view showing an outline of a circuit breaker using the arc extinguishing device of the first embodiment.

FIG. 3 is an exploded perspective view showing an outline of a circuit breaker according to a second embodiment of the present invention and a perspective perspective view of an arc extinguishing device.

FIG. 4 is a schematic diagram showing an outline of a circuit breaker according to a third embodiment of the present invention and an internal structure of an arc extinguishing device.

5A and 5B are exploded perspective views of a fixed terminal block 26 and the like, and FIG. 5B is a perspective view showing a state in which the fixed terminal block 26 and the like are assembled, and FIG. It is a perspective view of an apparatus.

FIG. 6 is an exploded perspective view showing an outline of a circuit breaker according to a fourth embodiment.

FIG. 7 is an exploded perspective view showing an outline of a circuit breaker according to a fifth embodiment of the present invention.

FIG. 8 is a schematic side view showing the internal structure of a conventional circuit breaker.

FIG. 9 is a front perspective view showing a conventional circuit breaker.

FIG. 10 is a perspective view of a conventional arc extinguishing device and an exploded perspective view thereof.

[Explanation of symbols]

1 ... Molded case, 2 ... Cover, 3 ... Handle,
4 ... Arc extinguishing device, 5 ... Power supply side terminal block, 6 ... Tripping /
Open / close mechanism, 7 ... Fixed contact, 8 ... Movable contact stand, 9
... current transformer (CT), 10 ... zero-phase current transformer (ZCT),
11 ... Penetration conductor (load side terminal block), 12 ... Power supply lead wire, 17 ... Tripping relay part, 18 ... Load side lead wire, 21 ... Arc extinguishing plate, 22 ... Side plate, 23 ... Side plate A,
24 ... Top plate, 25 ... Molding material, 26 ... Fixed terminal block, 27 ... Fixed contact, 28 ... Current transformer (CT),
29 ... Zero-phase current transformer (ZCT), 30 ... Moving contact,
210 ... Protrusion, 230 ... Groove, 232 ... Hole, 240
…rail

Claims (5)

[Claims] 1. One or two or more poles each provided with a pair of contacts configured to be able to contact / separate each other, an opening / closing mechanism for contacting / separating the contacts, and one or more of the poles. An arc extinguishing device provided for each of them for extinguishing the arc gas generated due to the contact / separation, and the arc extinguishing device of each pole is integrated with each other. Circuit breaker. 2. The arc-extinguishing device comprises a plurality of arc-extinguishing plates, and a supporting member for supporting the arc-extinguishing plates, the whole of which is integrally molded with a support member. Circuit breaker. 3. A contact base having one of two contacts forming the pair of contacts, wherein the contact base is integrated with the arc extinguishing device. The circuit breaker according to claim 2. 4. A current transformer that detects a current flowing through each of the poles and a zero-phase current transformer that detects a leakage current. The current transformer and the zero-phase current transformer are integrated with the arc extinguishing device. The circuit breaker according to claim 3, wherein the circuit breaker is an integrated circuit breaker. 5. The circuit breaker according to claim 2, 3 or 4, wherein the support member constitutes a part of an outer shell of the circuit breaker.